WorldWideScience

Sample records for chloramphenicol

  1. Chloramphenicol Injection

    Science.gov (United States)

    ... an arm or leg sudden changes in vision pain with eye movement Chloramphenicol injection may cause a condition called gray syndrome in premature and newborn infants. There have also been reports of gray ...

  2. Chloramphenicol induced maculopapular rashes

    Directory of Open Access Journals (Sweden)

    Prashant Wadagbalkar

    2015-02-01

    Full Text Available Chloramphenicol is a broad spectrum antibiotic that acts by inhibiting protein synthesis. Though systemic use is rare, their topical preparations are commonly used. Allergic reaction due to chloramphenicol ear drops are less reported. Here, we have reported a maculopapular exanthema due to use of chloramphenicol ear drops. [Int J Basic Clin Pharmacol 2015; 4(1.000: 179-180

  3. Compound list: chloramphenicol [Open TG-GATEs

    Lifescience Database Archive (English)

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

  4. Chloramphenicol and acute esophagitis in the emergency department

    Directory of Open Access Journals (Sweden)

    Chad T Andicochea

    2015-01-01

    Full Text Available Even with its broad spectrum and low cost, concern over chloramphenicol′s adverse effects limited its use in the United States during the 1980s. Reports from United Kingdom and China in the 1990s demonstrated a low incidence of blood dyscrasias with the topical preparation of chloramphenicol, and showed continued good efficacy and low cost. Today, topical chloramphenicol is being used by some groups within otolaryngology and ophthalmology in the United States. As a result, emergency physicians are once again considering chloramphenicol-induced side effects in patients presenting to the emergency department. To date, there have been no published reports associating chest pain, dyspnea with chloramphenicol use, and there has only been one report of fungal esophagitis associated with topical chloramphenicol. We present a 31-year-old woman, 4 months status post tympanoplasty with a modified radical canal wall down mastoidectomy due to a cholesteatoma involving the epitympanum who had a residual tympanic membrane defect. She presented to the emergency department with chest "burning", with no other symptoms shortly after starting treatment with an insufflated combination antibiotic containing chloramphenicol. After ruling out cardiopulmonary or vascular etiology, she was treated successfully with a gastrointestinal cocktail cocktail for presumed esophagitis secondary to newly prescribed chloramphenicol.

  5. Bioavailability, pharmacokinetics and residues of chloramphenicol in the chicken.

    Science.gov (United States)

    Anadón, A; Bringas, P; Martinez-Larrañaga, M R; Diaz, M J

    1994-02-01

    The pharmacokinetic properties of chloramphenicol were determined in broiler chickens after two single oral doses (30 and 50 mg/kg body weight) and after a single intravenous (i.v.) dose (30 mg/kg body weight). After oral and i.v. administration, the plasma concentration-time graph was characteristic of a two-compartment open model. After oral administration (30 and 50 mg/kg), chloramphenicol was absorbed rapidly (time to maximal concentration of 0.72 or 0.60 h) and eliminated with a mean half-life (t1/2 beta) of 6.87 or 7.41 h, respectively. The bioavailability was 29% at 30 mg/kg chloramphenicol and 38% at 50 mg/kg chloramphenicol. Concentrations greater than 5 micrograms/ml were achieved at 15 min and persisted up to 2 or 4 h post-administration, respectively. Statistically significant differences between the two routes of administration were found for the pharmacokinetic variables, half-lives of both distribution and elimination phases (t1/2 alpha, t1/2 beta) and apparent volume of distribution [Vd(area)]. The mean t1/2 beta of chloramphenicol and i.v. administration was 5.23 h. Chloramphenicol was extensively metabolized into dehydrochloramphenicol (DH-CAP), nitrophenylaminopropanedione (NPAP) and nitroso-chloramphenicol (NO-CAP) derivatives. Residues of chloramphenicol (CAP) and the three metabolites DH-CAP, NPAP and NO-CAP in kidney, liver and muscle were measured in chickens that received an oral dose of 50 mg/kg once daily for 4 days. The results indicate that CAP and DH-CAP residues were cleared slowly and were at or below the detection limit of 0.005 microgram/ml within 12 days after dosing. However, at the time of slaughter (12 days), the NPAP and NO-CAP residues were detected in the tissue.

  6. Discrimination of eight chloramphenicol isomers by liquid chromatography tandem mass spectrometry in order to investigate the natural occurence of chloramphenicol

    NARCIS (Netherlands)

    Berendsen, B.J.A.; Zuidema, T.; Jong, de J.; Stolker, A.A.M.; Nielen, M.W.F.

    2011-01-01

    This paper describes the discrimination of eight different isomers of chloramphenicol (CAP), an antibiotic banned for use in food producing animals, by reversed phase and chiral liquid chromatography in combination with tandem mass spectrometric detection. Previously, by liquid chromatography couple

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

    Energy Technology Data Exchange (ETDEWEB)

    Scherk, F.; Agthe, O.

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

  8. [Real-time UV imaging of chloramphenicol intrinsic dissolution characteristics from ophthalmic in situ gel].

    Science.gov (United States)

    Chen, Jian-Xiu; Guo, Zhen; Li, Hai-Yan; Wu, Li; He, Zhong-Gui; Hu, Rong-Feng; Zhang, Ji-Wen

    2013-07-01

    In this paper, chloramphenicol was selected as a model drug to prepare in situ gels. The intrinsic dissolution rate of chloramphenicol from in situ gel was evaluated using the surface dissolution imaging system. The results indicated that intrinsic dissolution rate of chloramphenicol thermosensitive in situ gel decreased significantly when the poloxamer concentration increased. The addition of the thickener reduced the intrinsic dissolution rate of chloramphenicol thermosensitive gel, wherein carbomer had the most impact. Different dilution ratios of simulated tear fluid greatly affected gel temperature, and had little influence on the intrinsic dissolution rate of chloramphenicol from the thermosensitive in situ gel. The pH of simulated tear fluid had little influence on the intrinsic dissolution rate of chloramphenicol thermosensitive in situ gel. For the pH sensitive in situ gel, the dissolution rates of chloramphenicol in weak acidic and neutral simulated tear fluids were slower than that in weak alkaline simulated tear fluid. In conclusion, the intrinsic dissolution of chloramphenicol from in situ gel was dependent on formulation and physiological factors. With advantages of small volume sample required and rapid detection, the UV imaging method can be an efficient tool for the evaluation of drug release characteristics of ophthalmic in situ gel.

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

    Institute of Scientific and Technical Information of China (English)

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

    2009-01-01

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

  10. Quantitative trace analysis of eight chloramphenicol isomers in urine by chiral liquid chromatography coupled to tandem mass spectrometry

    NARCIS (Netherlands)

    Berendsen, B.J.A.; Essers, M.L.; Stolker, A.A.M.; Nielen, M.W.F.

    2011-01-01

    Chloramphenicol is a broad-spectrum antibiotic with, apart from its human medicinal use, veterinary abuse in all major food-producing animals. Chloramphenicol occurs in four stereoisomers (all para-nitro substituted) and furthermore four meta-nitro analogs of chloramphenicol exist. In this paper the

  11. Phosphorylation of chloramphenicol by a recombinant protein Yhr2 from Streptomyces avermitilis MA4680.

    Science.gov (United States)

    Rajesh, Thangamani; Sung, Changmin; Kim, Hyeonjeong; Song, Eunjung; Park, Hyung-Yeon; Jeon, Jong-Min; Yoo, Dongwon; Kim, Hyun Joong; Kim, Yong Hyun; Choi, Kwon-Young; Song, Kyung-Guen; Yang, Yung-Hun

    2013-06-15

    Although phosphorylation of chloramphenicol has been shown to occur in the chloramphenicol producer, Streptomyces venezuelae, there are no reports on the existence of chloramphenicol phosphorylase in other Streptomyces species. In the present study, we report the modification of chloramphenicol by a recombinant protein, designated as Yhr2 (encoded by SAV_877), from Streptomyces avermitilis MA4680. Recombinant Yhr2 was expressed in Escherichia coli BL21 (DE3) and the cells expressing this recombinant protein were shown to phosphorylate chloramphenicol to a 3'-O-phosphoryl ester derivative, resulting in an inactivated form of the antibiotic. Expression of yhr2 conferred chloramphenicol resistance to E. coli cells up to 25 μg/mL and in an in vitro reaction, adenosine triphosphate (ATP), guanosine triphosphate (GTP), adenosine diphosphate (ADP) and guanosine diphosphate (GDP) were shown to be the phosphate donors for phosphorylation of chloramphenicol. This study highlights that antibiotic resistance conferring genes could be easily expressed and functionalized in other organisms that do not produce the respective antibiotic.

  12. Gas chromatographic determination of chloramphenicol residues in shrimp: interlaboratory study.

    Science.gov (United States)

    Munns, R K; Holland, D C; Roybal, J E; Storey, J M; Long, A R; Stehly, G R; Plakas, S M

    1994-01-01

    An interlaboratory study of a gas chromatographic method for determining chloramphenicol (CAP) residues in shrimp was conducted. An internal standard (Istd), the meta isomer of CAP, was added to the shrimp, and the treated shrimp were homogenized with ethyl acetate. The ethyl acetate extract was defatted with hexane, and the CAP was partitioned into ethyl acetate from an aqueous salt solution. The ethyl acetate was evaporated, and the dried residue was treated with Sylon, a trimethylsilyl derivatizing agent, to yield the trimethylsilyl derivative of CAP. A portion of the solution containing the derivative was injected into a gas chromatograph equipped with an electron capture detector. Levels of fortified and incurred CAP were calculated from the peak area ratio of standard CAP to Istd. Recoveries of CAP from tissue directly fortified at 5 ppb were 102% (within-laboratory relative standard deviation [RSDr] = 5.6%), 104% (RSDr = 5.5%), and 108% (RSDr = 6.3%) from Laboratories 1, 2, and 3, respectively. Incurred-CAP residues at 5 and 10 ppb levels were also determined, with the following results: Laboratory 1: composite A, 4.56 ppb (RSDr = 14.0%); composite B, 8.38 ppb (RSDr = 11.6%); Laboratory 2: composite A, 4.17 ppb (RSDr = 12.5%); composite B, 8.90 ppb (RSDr = 5.60%); Laboratory 3: composite A, 4.66 ppb (RSDr = 14.9%); composite B, 11.0 ppb (RSDr = 11.8%).

  13. 75 FR 55810 - Withdrawal of Approval of New Animal Drug Applications; Chloramphenicol, Lincomycin, Pyrantel...

    Science.gov (United States)

    2010-09-14

    ...; Chloramphenicol, Lincomycin, Pyrantel Tartrate, and Tylosin Phosphate and Sulfamethazine AGENCY: Food and Drug..., NE 68127 Feed Service Co., NADA 138-342 TYLAN 5 Sec. 558.630 Inc., 303 Lundin Sulfa-G Premix...

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

    Science.gov (United States)

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

    2015-11-01

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

  15. The Binding Interactions of the Macrolide Endectocide Ivermectin with the Antibiotics Ampicillin, Chloramphenicol and Tetracycline HCL

    OpenAIRE

    Kandeel, M.; Elgazar, W.; Kitade, Y.

    2012-01-01

    Ivermectin, chloramphenicol, ampicillin and tetracycline HCl are common drugs in human and veterinary practice. The purpose of this study is to investigate the possible binding interactions between ivermectin and the antibiotics chloramphenicol, ampicillin and tetracycline HCl. Isothermal titration calorimetry was used to determine the binding interactions between ivermectin and these antibiotics. Results indicated that, about three molecules of ampicillin can bind to one molecule of ivermect...

  16. γ-Cyclodextrin capped silver nanoparticles for molecular recognition and enhancement of antibacterial activity of chloramphenicol.

    Science.gov (United States)

    Gannimani, Ramesh; Ramesh, Muthusamy; Mtambo, Sphamandla; Pillay, Karen; Soliman, Mahmoud E; Govender, Patrick

    2016-04-01

    Computational studies were conducted to identify the favourable formation of the inclusion complex of chloramphenicol with cyclodextrins. The results of molecular docking and molecular dynamics predicted the strongest interaction of chloramphenicol with γ-cyclodextrin. Further, the inclusion complex of chloramphenicol with γ-cyclodextrin was experimentally prepared and a phenomenon of inclusion was verified by using different characterization techniques such as thermogravimetric analysis, differential scanning calorimetry, (1)H nuclear magnetic resonance (NMR) and two dimensional nuclear overhauser effect spectroscopy (NOESY) experiments. From these results it was concluded that γ-cyclodextrins could be an appropriate cyclodextrin polymer which can be used to functionalize chloramphenicol on the surface of silver nanoparticles. In addition, γ-cyclodextrin capped silver nanoparticles were synthesized and characterized using UV-visible spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), Fourier transform infrared spectroscopy (FTIR) and zeta potential analysis. Molecular recognition of chloramphenicol by these cyclodextrin capped silver nanoparticles was confirmed by surface enhanced raman spectroscopy (SERS) experiments. Synergistic antibacterial effect of chloramphenicol with γ-cyclodextrin capped silver nanoparticles was evaluated against Pseudomonas aeruginosa (ATCC 27853), Enterococcus faecalis (ATCC 5129), Klebsiella pneumoniae (ATCC 700603) and Staphylococcus aureus (ATCC 43300). The results from the antibacterial experiment were favourable thus allowing us to conclude that the approach of modifying organic drug molecules with cyclodextrin capped inorganic silver nanoparticles could help to enhance the antibacterial activity of them.

  17. Discrimination of eight chloramphenicol isomers by liquid chromatography tandem mass spectrometry in order to investigate the natural occurrence of chloramphenicol.

    Science.gov (United States)

    Berendsen, Bjorn J A; Zuidema, Tina; de Jong, Jacob; Stolker, Linda A A M; Nielen, Michel W F

    2011-08-26

    This paper describes the discrimination of eight different isomers of chloramphenicol (CAP), an antibiotic banned for use in food producing animals, by reversed phase and chiral liquid chromatography in combination with tandem mass spectrometric detection. Previously, by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) the presence of CAP was confirmed in some grass and herb samples collected on Mongolian pastures up to concentrations of 450 μg kg(-1). It was not possible to establish the cause of CAP residues which has initiated research on the natural occurrence of this drug. CAP occurs in the para-configuration and in the meta-configuration and contains two chiral centers thus eight different isomeric configurations exist, namely four (RR, SS, RS, SR) meta-stereoisomers and four para-stereoisomers. It is known that only RR-p-CAP has antimicrobial properties. To find out if the CAP detected in the plant material samples is the active configuration, a high resolution reversed phase LC-MS/MS system was tested for its ability to separate the different isomers. This system proved to be able to discriminate between some isomers, but not between RR-p-CAP and SS-p-CAP, also called dextramycin. Despite a detailed elucidation of the product ions and the fragmentation patterns of all isomers, MS/MS did not add sufficient specificity for full discrimination of the isomers. Therefore a chiral liquid chromatographic separation with MS/MS detection that is able to distinguish all isomers was developed and finally the isomeric ratio of non-compliant plant material samples and some CAP formulations was determined using this system. This showed that Mongolian grass and herb samples only contain the biological active isomer of CAP as do the obtained formulations. Therefore the CAP present in the plant material might origin from the production by soil organisms or from a manufactured source.

  18. Widespread ocular use of topical chloramphenicol: is there justifiable concern regarding idiosyncratic aplastic anaemia?

    Science.gov (United States)

    McGhee, C N; Anastas, C N

    1996-02-01

    A theoretical but as yet not conclusively proved risk of chloramphenicol induced idiosyncratic aplastic anaemia exists with topical ophthalmic therapy, with the absolute, but highly improbable, maximum risk of death (equalling that of systemic therapy) being 1 in 50,000 to 90,000. To put this in realistic perspective, one must note that the comparable risk of fatal anaphylaxis resulting from penicillin therapy, from any route, is similar at 1 in 100,000. Indeed, it has been noted recently that with more than 200 million ocular chloramphenicol products dispensed in the UK in the past 10 years, only 11 reports (all non-fatal) of suspected topical chloramphenicol induced blood dyscrasia have been reported to the Committee on the Safety of Medicines since 1966. One also has to consider that inadvertent exposure to minute quantities of chloramphenicol (ng/ml) may occur through consumption of livestock that have been treated with chloramphenicol. Broad statements condemning topical chloramphenicol need to be tempered with its proved safety, tolerance, cost, and efficacy while acknowledging an extremely remote risk of the very serious adverse effect of drug induced aplastic anaemia. Risk-benefit assessment is the duty of all prescribing physicians and a decision to prescribe or not prescribe must be made on the basis of personal judgment and an awareness of the statistics in perspective. The only known factor to be associated with vulnerability in the case of topical chloramphenicol is family history. There is no evidence to date that suggests children are any more susceptible than adults.

  19. Chloramphenicol – A Potent Armament Against Multi-Drug Resistant (MDR) Gram Negative Bacilli?

    Science.gov (United States)

    2016-01-01

    Introduction Multidrug-resistant gram-negative bacteria cause infections which are hard to treat and cause high morbidity and mortality. Due to limited therapeutic options there is a renewed interest upon older antimicrobials which had fallen into disuse as a result of toxic side effects. One such antibiotic is chloramphenicol which was sidelined due to reports linking its use with the development of aplastic anaemia. Aim A study was conducted to evaluate the susceptibility of chloramphenicol in light of the emerging problem of multi-drug resistant gram negative bacteria (MDR GNB). Materials and Methods A total of 483 MDR GNB of the 650 consecutive Gram Negative Bacteria isolated from various clinical samples of patients admitted at a tertiary care hospital in Jaipur between January-June 2014 were screened for chloramphenicol susceptibility by the disc diffusion method as per CLSI guidelines. Results The MDR GNB isolates were obtained from 217 (45%) urine, 163 (34%) from respiratory samples, 52(11%) from pus, 42 (9%) from blood and 9 (2%) from body fluids. A 68% of the MDR GNB isolates were found to be sensitive to chloramphenicol. Conclusion Clinicians should always check for the local susceptibility of Gram-negative bacteria to chloramphenicol. This antibiotic has a potential to play a role in the therapeutic management of infections due to MDR GNB pathogens. PMID:27042458

  20. Stability-Indicating HPTLC Method for Simultaneous Estimation of Flurbiprofen and Chloramphenicol in Ophthalmic Solution.

    Science.gov (United States)

    Sadakwala, Vaishnavi M; Chauhan, Renu S; Shah, Shailesh A; Shah, Dinesh R

    2016-01-01

    A specific, accurate and reproducible stability-indicating high performance thin layer chromatography (HPTLC) method was developed for the estimation of flurbiprofen and chloramphenicol in the presence of their degradation products. Degradation studies of both the drugs were carried out in acidic, alkaline, neutral, oxidative, photolytic and thermal stress conditions. Separation was performed on thin layer chromatography plate precoated with silica gel 60 F254 using ethyl acetate : n-hexane : methanol : tri-ethyl amine (5 : 4 : 2 : 0.5, v/v/v/v). Spots at retention factor 0.29 and 0.62 were recognized as flurbiprofen and chloramphenicol, respectively, and were quantified through densitometric measurements at wavelength 267 nm. Method was found to be linear over the concentration range 12-60 ng/spot with correlation coefficient of 0.9997 for flurbiprofen and 200-1,000 ng/spot with correlation coefficient of 0.9977 for chloramphenicol. The proposed method was applied to the estimation of flurbiprofen and chloramphenicol in commercial ophthalmic formulation. The developed HPTLC method can be applied for routine analysis of flurbiprofen and chloramphenicol in the presence of their degradation products in their individual as well as combined pharmaceutical formulations.

  1. Uroporphyria development in cultured chick embryo fibroblasts long-term treated with chloramphenicol and ethidium bromide.

    Science.gov (United States)

    de Muys, J M; Morais, R

    1984-07-23

    Long-term chloramphenicol- and ethidium bromide-treated chick embryo fibroblasts synthesize large amounts of porphyrins from exogenously added delta-aminolevulinic acid. The porphyrins consist mainly of uro- and heptacarboxyporphyrins and are retained within cells. Uroporphyria development is a time-dependent process which accompanies a step-wise decrease in the capacity of the mitochondrial respiratory chain. Upon removal of chloramphenicol from the medium, the pattern of porphyrin production readily returns to normal (mainly proto- and coproporphyrins found in the medium) while ethidium bromide-treated cells remain uroporphyric. The results suggest that impairment of mitochondrial functions in chicken by xenobiotics leads to uroporphyria development.

  2. Responses of Wild-Type and Resistant Strains of the Hyperthermophilic Bacterium Thermotoga maritima to Chloramphenicol Challenge▿ †

    Science.gov (United States)

    Montero, Clemente I.; Johnson, Matthew R.; Chou, Chung-Jung; Conners, Shannon B.; Geouge, Sarah G.; Tachdjian, Sabrina; Nichols, Jason D.; Kelly, Robert M.

    2007-01-01

    Transcriptomes and growth physiologies of the hyperthermophile Thermotoga maritima and an antibiotic-resistant spontaneous mutant were compared prior to and following exposure to chloramphenicol. While the wild-type response was similar to that of mesophilic bacteria, reduced susceptibility of the mutant was attributed to five mutations in 23S rRNA and phenotypic preconditioning to chloramphenicol. PMID:17557852

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

    Directory of Open Access Journals (Sweden)

    Budimir S. Ilić

    2014-01-01

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

  4. Limitations when use chloramphenicol-bcyclodextrins complexes in ophtalmic solutions buffered with boric acid/borax system

    Directory of Open Access Journals (Sweden)

    Todoran Nicoleta

    2014-12-01

    Full Text Available Chloramphenicol eye drops are commonly prescribed in concentrations of 0.5-1% in the treatment of infectious conjunctivitis. In terms of ophthalmic solution preparation, the major disadvantage of chloramphenicol consists in its low solubility in water. The solubility is increased by substances that form chloramphenicol-complexes, for example: boric acid/borax or cyclodextrins. Objective: Experimental studies aimed to evaluate the potential advantages of enhancing the solubility and stability of chloramphenicol (API by molecular encapsulation in b-cyclodextrin (CD, in formulation of ophthalmic solutions buffered with boric acid/borax system. Methods and Results: We prepared four APIb- CD complexes, using two methods (kneading and co-precipitation and two molar ratio of API/b-cyclodextrin (1:1 and 1:2. The formation of complexes was proved by differential scanning calorimetry (DSC and the in vitro dissolution tests. Using these compounds, we prepared eight ophthalmic solutions, formulated in two variants of chloramphenicol concentrations (0.4% and 0.5%. Each solution was analyzed, by the official methods, at preparation and periodically during three months of storing in different temperature conditions (4°C, 20°C and 30°C. Conclusions: Inclusion of chloramphenicol in b-cyclodextrin only partially solves the difficulties due to the low solubility of chloramphenicol. The protection of chloramphenicol molecules is not completely ensured when the ophthalmic solutions are buffered with the boric acid/borax system.

  5. Chloramphenicol- and tetracycline-resistant uropathogenic Escherichia coli (UPEC) exhibit reduced virulence potential.

    Science.gov (United States)

    Starcic Erjavec, Marjanca; Rijavec, Matija; Krizan-Hergouth, Veronika; Fruth, Angelika; Zgur-Bertok, Darja

    2007-11-01

    It is well documented that uropathogenic Escherichia coli (UPEC) isolates resistant to nalidixic acid have reduced virulence potential. Our goal was to assess whether UPEC isolates resistant to chloramphenicol, tetracycline and streptomycin also exhibit reduced virulence potential. Among 110 human UPEC isolates, the prevalences of the virulence factors fimH, papC, papGII, papGIII, sfa/focDE, afa, hlyA, cnf1, usp, ibeA, fyuA, iroN, iucD, ireA, and K1 and K5 capsules as well as of pathotypes, phylogenetic groups, O antigens and a pathogenicity island (PAI) marker were compared between chloramphenicol-, tetracycline-, streptomycin- and, as a control, nalidixic acid-resistant and -susceptible strains. Our findings show that among human UPEC isolates, not only nalidixic acid-resistant but also chloramphenicol- and tetracycline-resistant isolates have reduced virulence potential compared with susceptible strains. To our knowledge, this is the first report of a statistically significant reduction in virulence traits among chloramphenicol- and tetracycline-resistant isolates.

  6. Adverse events associated with chloramphenicol use in dogs: a retrospective study (2007-2013).

    Science.gov (United States)

    Short, J; Zabel, S; Cook, C; Schmeitzel, L

    2014-11-29

    Chloramphenicol is a broad spectrum antibiotic that has been increasingly utilised since the emergence of methicillin-resistant staphylococcal infections. Due to toxicities in humans, use of the drug has been limited. In dogs, gastrointestinal signs are common adverse events described, and bone marrow suppression is possible. The aim of this study was to evaluate the adverse events associated with chloramphenicol in dogs seen by one specialty practice from January 2007 through June 2013. The database was searched for all dogs prescribed chloramphenicol during the time period. Dosage, length of treatment, age and body weight of the dogs were recorded as well as any adverse events that occurred during treatment. A total of 105 cases were evaluated. Thirty-nine dogs experienced at least one adverse event while on the medication. The most commonly noted were gastrointestinal signs and hindlimb weakness. The mean body weight for dogs with hindlimb weakness was 35.3 kg, which was significant. Resolution was documented in 54 per cent of cases when the drug was discontinued. Methicillin-resistant Staphylococcus pseudintermedius on bacterial culture was listed as the reason for chloramphenicol use in 76 per cent of the cases. Based on this information, further prospective studies are recommended to evaluate the reproducibility of this report.

  7. The chloramphenicol acetyltransferase vector as a tool for stable tagging of Neospora caninum.

    Science.gov (United States)

    Pereira, Luiz Miguel; Yatsuda, Ana Patrícia

    2014-09-01

    Neospora caninum is an obligate intracellular Apicomplexa, a phylum where one of the current methods for functional studies relies on molecular genetic tools. For Toxoplasma gondii, the first method described, in 1993, was based on resistance against chloramphenicol. As in T. gondii, we developed a vector constituted of the chloramphenicol acetyltransferase gene (CAT) flanked by the N. caninum dihydrofolate reductase-thymidylate synthase (DHFR-TS) 5' coding sequence flanking region. Five weeks after transfection and under the selection of chloramphenicol the expression of CAT increased compared to the wild type and the resistance was retained for more than one year. Between the stop codon of CAT and the 3' UTR of DHFR, a Lac-Z gene controlled by the N. caninum tubulin 5' coding sequence flanking region was ligated, resulting in a vector with a reporter gene (Ncdhfr-CAT/NcTub-tetO/Lac-Z). The stability was maintained through an episomal pattern for 14 months when the tachyzoites succumbed, which was an unexpected phenomenon compared to T. gondii. Stable parasites expressing the Lac-Z gene allowed the detection of tachyzoites after invasion by enzymatic reaction (CPRG) and were visualised macro- and microscopically by X-Gal precipitation and fluorescence. This work developed the first vector for stable expression of proteins based on chloramphenicol resistance and controlled exclusively by N. caninum promoters.

  8. Meningitis Due to Ampicillin-and Chloramphenicol-Resistant Haemophilus influenzae Type B in Canada. Case Report and Review

    Directory of Open Access Journals (Sweden)

    Amin Kabani

    1990-01-01

    Full Text Available The first report of a case of ampicillin- and chloramphenicol-resistant Haemophilus influenzae type b invasive infection in Canada is described in a four-month-old male with meningitis. He was treated with cefotaxime 200 mg/kg/day divided every 6 h and dexamethasone 0.6 mg/kg/day divided every 6 h, eventually recovering after a complicated course. Follow-up at 21 months showed mild to moderate global developmental delay. While chloramphenicol resistance is rare in North America, a case of meningitis initially unresponsive to ampicillin and chloramphenicol must be considered suspect for resistance. Third generation cephalosporins should be used for resistant cases.

  9. Study of Stability Constants of Fe (Iii And Mn (Ii with Chloramphenicol by Paper Electrophoretic Technique

    Directory of Open Access Journals (Sweden)

    Arvind Singh

    2014-12-01

    Full Text Available Stabilty constant of binary complexes of Fe(III and Mn(II with medicinally important ligand chloramphenicol antibiotics in solution were determined by paper electrophoretic technique. Stability constant of the complexes were determined at 25°C temperature and 0.1M (HClO4 ionic strength. Our study is based upon the migration of a spot of metal ions on a paper strip at different pH against mobility gives information about the binary complexes and permits to calculate their stability constant. The stability constant data revealed that chloramphenicol may be used as chelating agent in chelation for medical treatment of metal overload or poisoning.

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

    Indian Academy of Sciences (India)

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

    2005-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, D.; Somgyi, A.

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

  12. Exposure to topical chloramphenicol during pregnancy and the risk of congenital malformations

    DEFF Research Database (Denmark)

    Thomseth, Vilde; Cejvanovic, Vanja; Jimenez-Solem, Espen

    2015-01-01

    malformations (adjusted odds ratio = 1.06, 95% CI 0.91-1.22) or specific major malformations. The number of redeemed prescriptions decreased significantly during pregnancy as compared to before and after pregnancy (p ...PURPOSE: To investigate whether exposure to topical chloramphenicol in the first trimester of pregnancy is associated with congenital malformations. METHODS: The authors conducted a nationwide cohort study including all women giving live birth between 1997 and 2011 in Denmark. All women redeeming...... at least one prescription of chloramphenicol eye drops or eye ointment during the first 84 days of pregnancy were identified. Logistic regression was used to estimate the odds ratios of malformations among exposed women compared to non-exposed women. RESULTS: 966 372 births between 1997 and 2011 were...

  13. Transmissible Resistance to Penicillin G, Neomycin, and Chloramphenicol in Rhizobium japonicum1

    Science.gov (United States)

    Cole, Michael A.; Elkan, Gerald H.

    1973-01-01

    The genetic basis for resistance to a number of antibiotics was examined in Rhizobium japonicum. Resistance to penicillin G, neomycin, and chloramphenicol appears to be mediated by an extrachromosomal element similar to that found in the Enterobacteriaceae. Resistance to these antibiotics was eliminated from cells by treatment with acridine orange, and resistance to all three antibiotics could be transferred en bloc to Agrobacterium tumefaciens under conditions excluding transformation or transduction as possible genetic mechanisms. PMID:4491197

  14. Chloramphenicol improved expression of recombinant cholera toxin B subunit in Escherichia coli and its adjuvanticity

    Institute of Scientific and Technical Information of China (English)

    XIE Xiao-yan; WAN Yan-min; ZHU Zhao-qin; ZHANG Huan-xiang; XU Jian-qing

    2011-01-01

    Background Cholera toxin B subunit (CTB) was shown to be a potent adjuvant for protein immunogen,especially when inoculated through mucosal route.We aimed to optimize the expression approach for CTB and thereafter to determine the adjuvant effect on DNA vaccine.Methods Wild type CTB coding gene was amplified and cloned into prokaryotic expression vector pET-30a,and the recombinant CTB was expressed in the presence of different concentration of chloramphenicol and isopropyl β-D-thiogalactoside.Purified recombinant CTB was mixed with HIV-1 AE2f tat-rev-integrase-vif-nef fusion gene DNA vaccine and female BALB/c mice were vaccinated with a DNA priming-recombinant vaccinia vectored vaccine boosting regimen through intramuscular injection.Interferon y (IFN-γ) enzyme-linked immunospot (Elispot) assay was used to read out the specific T-cell immunity.Results Chloramphenicol was essential for the efficient expression of recombinant CTB (rCTB) in pET-30a/BL21 (DE3)system and could be optimized at the concentration of 0.625 μg/ml in the presence of chloramphenicol.The purified rCTB could bind with GM1 efficiently.INF-y Elispot data showed the T-cell response induced in CTB adjuvanted group ((734±240) spot forming cells/106 splenocytes) was higher than that induced by non-adjuvanted ((520±150) spot forming cells/106 splenocytes),ail responses against different antigens were enhanced in parallel.Conclusion CTB could be efficiently expressed in the presence of chloramphenicol and purified CTB is functional and capable of enhancing the specific T cell responses elicited by DNA vaccine,the mechanism needs to be explored in the future.

  15. Induction of cat-86 by chloramphenicol and amino acid starvation in relaxed mutants of Bacillus subtilis.

    Science.gov (United States)

    Ambulos, N P; Rogers, E J; Alexieva, Z; Lovett, P S

    1988-12-01

    The chloramphenicol acetyltransferase gene cat-86 is induced through a mechanism that is a variation of classical attenuation. Induction results from the destabilization of an RNA stem-loop that normally sequesters the cat-86 ribosome-binding site. Destabilization of the stem-loop is due to the stalling of a ribosome in the leader region of cat-86 mRNA at a position that places the A site of the stalled ribosome at leader codon 6. Two events can stall ribosomes at the correct location to induce cat-86 translation: addition of chloramphenicol to cells and starvation of cells for the amino acid specified by leader codon 6. Induction by amino acid starvation is an anomaly because translation of the cat-86 coding sequence requires all 20 amino acids. To explain this apparent contradiction we postulated that amino acid starvation triggers intracellular proteolysis, thereby providing levels of the deprived amino acid sufficient for cat-86 translation. Here we show that a mutation in relA, the structural gene for stringent factor, blocks intracellular proteolysis that is normally triggered by amino acid starvation. The relA mutation also blocks induction of cat-86 by amino acid starvation, but the mutation does not interfere with chloramphenicol induction. Induction by amino acid starvation can be demonstrated in relA mutant cells if the depleted amino acid is restored at very low levels (e.g., 2 micrograms/ml). A mutation in relC, which may be the gene for ribosomal protein L11, blocks induction of cat-86 by either chloramphenicol or amino acid starvation. We believe this effect is due to a structural alteration of the ribosome resulting from the relC mutation and not to the relaxed phenotype of the cells.

  16. Chloramphenicol induction of cat-86 requires ribosome stalling at a specific site in the leader.

    Science.gov (United States)

    Alexieva, Z; Duvall, E J; Ambulos, N P; Kim, U J; Lovett, P S

    1988-05-01

    The plasmid gene cat-86 specifies chloramphenicol-inducible chloramphenicol acetyltransferase in Bacillus subtilis. Induction by the antibiotic is primarily due to activation of the translation of cat-86-encoded mRNA. It has been suggested that the inducer stalls ribosomes at a discrete location in the leader region of cat-86 mRNA, which causes the destabilization of a downstream RNA secondary structure that normally sequesters the cat-86 ribosome binding site. It is the destabilization of this RNA secondary structure that permits translation of the cat-86 coding sequence. In the present report, we show that ribosomes that were stalled in the cat-86 leader by starvation of host cells for the amino acid specified by leader codon 6 induced gene expression to a level above that detected when cells were starved for the amino acids specified by leader codons 7 and 8. Starvation for amino acids specified by leader codons 3, 4, or 5 failed to activate cat-86 expression. These results indicate that the stalled ribosome that is most active in cat-86 induction has its aminoacyl site occupied by leader codon 6. To determine if chloramphenicol also stalled ribosomes in the cat-86 regulatory leader such that the aminoacyl site was occupied by codon 6, we separately changed leader codons 3, 4, 5, and 6 to the translation termination (ochre) codon TAA. Each of the mutated genes was tested for its ability to be induced by chloramphenicol. The results show that replacement of leader codons 3, 4, or 5 by the ochre codon blocked induction, whereas replacement of leader codon 6 by the ochre codon permitted induction. Collectively, these observations lead to the conclusion that cat-86 induction requires ribosome stalling in leader mRNA, and they identify leader codon 6 as the codon most likely to be occupied by the aminoacyl site of a stalled ribosome that is active in the induction.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-05-15

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

  18. Simultaneous Chloramphenicol and Florfenicol Determination by A Validated DLLME-HPLC-UV Method in Pasteurized Milk.

    Science.gov (United States)

    Karami-Osboo, Rouhollah; Miri, Ramin; Javidnia, Katayoun; Kobarfard, Farzad

    2016-01-01

    The antibiotic residues in milk are a well-known serious problem and pose several health hazards to consumers. We have described a simple, rapid, and inexpensive DLLME-HPLC/UV technique for the extraction of chloramphenicol and florfenicol residues in milk samples. Under the optimum conditions, linearity of the method was observed over the range 0.02-0.85 µg/L with correlation coefficients > 0.999. The proposed method has been found to have a good limit of detection (signal to noise ratio = 3) for chloramphenicol (12.5 µg/Kg) and florfenicol (12.2 µg/Kg), and precision with relative standard deviation values under 15% (RSD, n = 3). Good recoveries (69.1-79.4%) were obtained for the extraction of the target analytes in milk samples. This simple and economic method has been applied for analyses of 15 real milk samples. Among all samples only one of them was contaminated to florfenicol; 62.4 µg/Kg and contamination to chloramphenicol was not detected.

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

    Science.gov (United States)

    Kao, Li-Pin; Ovchinnikov, Dmitry; Wolvetang, Ernst

    2012-05-15

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

  20. Matrix molecularly imprinted mesoporous sol-gel sorbent for efficient solid-phase extraction of chloramphenicol from milk.

    Science.gov (United States)

    Samanidou, Victoria; Kehagia, Maria; Kabir, Abuzar; Furton, Kenneth G

    2016-03-31

    Highly selective and efficient chloramphenicol imprinted sol-gel silica based inorganic polymeric sorbent (sol-gel MIP) was synthesized via matrix imprinting approach for the extraction of chloramphenicol in milk. Chloramphenicol was used as the template molecule, 3-aminopropyltriethoxysilane (3-APTES) and triethoxyphenylsilane (TEPS) as the functional precursors, tetramethyl orthosilicate (TMOS) as the cross-linker, isopropanol as the solvent/porogen, and HCl as the sol-gel catalyst. Non-imprinted sol-gel polymer (sol-gel NIP) was synthesized under identical conditions in absence of template molecules for comparison purpose. Both synthesized materials were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and nitrogen adsorption porosimetry, which unambiguously confirmed their significant structural and morphological differences. The synthesized MIP and NIP materials were evaluated as sorbents for molecularly imprinted solid phase extraction (MISPE) of chloramphenicol in milk. The effect of critical extraction parameters (flow rate, elution solvent, sample and eluent volume, selectivity coefficient, retention capacity) was studied in terms of retention and desorption of chloramphenicol. Competition and cross reactivity tests have proved that sol-gel MIP sorbent possesses significantly higher specific retention and enrichment capacity for chloramphenicol compared to its non-imprinted analogue. The maximum imprinting factor (IF) was found as 9.7, whereas the highest adsorption capacity of chloramphenicol by sol-gel MIP was 23 mg/g. The sol-gel MIP was found to be adequately selective towards chloramphenicol to provide the necessary minimum required performance limit (MRPL) of 0.3 μg/kg set forth by European Commission after analysis by LC-MS even without requiring time consuming solvent evaporation and sample reconstitution step, often considered as an integral part in solid phase extraction work-flow. Intra and

  1. Specification of the immune response: its suppression induced by chloramphenicol in vitro.

    Science.gov (United States)

    Couderc, J; Perrodon, Y; Ventura, M; Liacopoulos, P; Danchin, A

    1983-01-01

    Specific in vitro PFC responses to trinitrophenyl conjugated to sheep red blood cells are inhibited by chloramphenicol (CAP), thiamphenicol (TAP), and diuron (DIU) by B-cell impairment. However, both mitogenic and polyclonal response to lipopolysaccharide is not affected by CAP and TAP but severely inhibited by DIU. Similarly, contact of cultured cells for the first 24 h with CAP did not much affect the 4th-day in vitro PFC response but the same incubation with DIU reduced it by 70%. Moreover, DIU used at the same concentration provoked an important mortality of cultured cells. These differences suggest that the target mechanism of CAP and TAP differs from that of DIU.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-03-01

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

  3. Matrix molecularly imprinted mesoporous sol–gel sorbent for efficient solid-phase extraction of chloramphenicol from milk

    Energy Technology Data Exchange (ETDEWEB)

    Samanidou, Victoria, E-mail: samanidu@chem.auth.gr [Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki (Greece); Kehagia, Maria [Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki (Greece); Kabir, Abuzar, E-mail: akabir@fiu.edu [International Forensic Research Institute, Department of Chemistry and Biochemistry, Florida International University, Miami, FL (United States); Furton, Kenneth G. [International Forensic Research Institute, Department of Chemistry and Biochemistry, Florida International University, Miami, FL (United States)

    2016-03-31

    Highly selective and efficient chloramphenicol imprinted sol–gel silica based inorganic polymeric sorbent (sol–gel MIP) was synthesized via matrix imprinting approach for the extraction of chloramphenicol in milk. Chloramphenicol was used as the template molecule, 3-aminopropyltriethoxysilane (3-APTES) and triethoxyphenylsilane (TEPS) as the functional precursors, tetramethyl orthosilicate (TMOS) as the cross-linker, isopropanol as the solvent/porogen, and HCl as the sol–gel catalyst. Non-imprinted sol–gel polymer (sol–gel NIP) was synthesized under identical conditions in absence of template molecules for comparison purpose. Both synthesized materials were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and nitrogen adsorption porosimetry, which unambiguously confirmed their significant structural and morphological differences. The synthesized MIP and NIP materials were evaluated as sorbents for molecularly imprinted solid phase extraction (MISPE) of chloramphenicol in milk. The effect of critical extraction parameters (flow rate, elution solvent, sample and eluent volume, selectivity coefficient, retention capacity) was studied in terms of retention and desorption of chloramphenicol. Competition and cross reactivity tests have proved that sol–gel MIP sorbent possesses significantly higher specific retention and enrichment capacity for chloramphenicol compared to its non-imprinted analogue. The maximum imprinting factor (IF) was found as 9.7, whereas the highest adsorption capacity of chloramphenicol by sol–gel MIP was 23 mg/g. The sol–gel MIP was found to be adequately selective towards chloramphenicol to provide the necessary minimum required performance limit (MRPL) of 0.3 μg/kg set forth by European Commission after analysis by LC-MS even without requiring time consuming solvent evaporation and sample reconstitution step, often considered as an integral part in solid phase extraction work

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

    Science.gov (United States)

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

    2016-04-15

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

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

    Institute of Scientific and Technical Information of China (English)

    MADANJitender; KAUSHIKDinesh; SARDANASatish; MISHRADn

    2007-01-01

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

  6. An amperometric chloramphenicol immunosensor based on cadmium sulfide nanoparticles modified-dendrimer bonded conducting polymer.

    Science.gov (United States)

    Kim, Dong-Min; Rahman, Md Aminur; Do, Minh Hien; Ban, Changill; Shim, Yoon-Bo

    2010-03-15

    An amperometric chloramphenicol (CAP) immunosensor was fabricated by covalently immobilizing anti-chloramphenicol acetyl transferase (anti-CAT) antibody on cadmium sulfide nanoparticles (CdS) modified-dendrimer that was bonded to the conducting polymer (poly 5, 2': 5', 2''-terthiophene-3'-carboxyl acid (poly-TTCA)) layer. The AuNPs, dendrimers, and CdS nanoparticles were deposited onto the polymer layer in order to enhance the sensitivity of the sensor probes. The particle sizes were determined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The immobilization of dendrimers, CdS, and anti-CAT were confirmed using energy disruptive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and quartz crystal microbalance (QCM) techniques. The detection of CAP was based on the competitive immuno-interaction between the free- and labeled-CAP for active sites of the anti-CAT. Hydrazine was used as the label for CAP, and it electrochemically catalyzed the reduction of H(2)O(2) at -0.35 V vs. Ag/AgCl. Under optimized conditions, the proposed immunosensor exhibited a linear range of CAP detection between 50 pg/mL and 950 pg/mL, and the detection limit was 45 pg/mL. The immunosensor was examined in real meat samples for the analysis of CAP.

  7. Pharmacokinetics of amikacin and chloramphenicol in the aqueous humor of rabbits.

    Science.gov (United States)

    Mayers, M; Rush, D; Madu, A; Motyl, M; Miller, M H

    1991-01-01

    Composite data describing ocular pharmacokinetics are unreliable because of intersubject variation. To address this problem, an animal model was developed in which multiple aqueous samples from single subjects were obtained. Following direct anterior chamber or intravenous administration of amikacin or chloramphenicol, pharmacokinetic analysis of drug concentrations in the serum and anterior chamber was performed by using a nonlinear least-squares regression program. The number of anterior chamber paracenteses performed did not alter the beta elimination rates or percent penetration into the anterior chamber. The aqueous humor and peripheral-compartment terminal slopes were identical. These data indicate that complete ocular concentration-time curves can be obtained without altering antibiotic pharmacokinetics. Following direct injection into the anterior chamber, the elimination rates for both antibiotics followed a one-compartment model, whereas those following intravenous administration best fit an open, first-order, two-compartment model. Following intravenous administration, the anterior chamber elimination rate constants for both drugs were equal to that of the serum and significantly longer than that following direct injection. The elimination rates of both drugs following direct injection were similar. Systemic administration resulted in drug levels in aqueous humor that persisted longer than those following direct injection. Chloramphenicol, a lipophilic compound, gave higher mean concentrations in aqueous humor than did amikacin. Our model provides a new approach which rigorously examines ocular pharmacokinetics and provides data which suggest that for selected compounds the parenteral route of administration is preferable. PMID:1952850

  8. Pharmacokinetics of a long-acting chloramphenicol formulation administered by intramuscular and subcutaneous routes in cattle.

    Science.gov (United States)

    Sanders, P; Guillot, P; Mourot, D

    1988-06-01

    The pharmacokinetic properties of a long-acting formulation of chloramphenicol were determined in six yearling cattle after a single intravenous (i.v.) administration (40 mg/kg body weight) and after two sequential subcutaneous (s.c.) or intramuscular (i.m.) administrations (90 mg/kg/48 h). The two extravascular routes were studied during a crossover trial for a bioequivalence test. After i.v. administration, the plasma concentration-time graph was characteristic of a two-compartment open model. Mean values were a half-life of 4.1 h, a volume of distribution of 0.86 l/kg and a body clearance of 0.128 l/kg/h. Plasma concentrations of chloramphenicol following i.m. and s.c. administrations increased slowly to a broad peak at 10-15 micrograms/ml between 9 and 12 h. Bioavailability was 19.1% after i.m. injection and 12.4% after s.c. administration. The extent of absorption from the two routes did not differ significantly. The rate of absorption was significantly lower after s.c. application than it was after i.m. injection. The time necessary for the plasma concentration to exceed 5 micrograms/ml was the same for the two routes. Thus, i.m. and s.c. routes are bioequivalent.

  9. Chloramphenicol with fluid and electrolyte therapy cures terminally ill green tree frogs (Litoria caerulea) with chytridiomycosis.

    Science.gov (United States)

    Young, Sam; Speare, Rick; Berger, Lee; Skerratt, Lee F

    2012-06-01

    Terminal changes in frogs infected with the amphibian fungal pathogen Batrachochytrium dendrobatidis (Bd) include epidermal degeneration leading to inhibited epidermal electrolyte transport, systemic electrolyte disturbances, and asystolic cardiac arrest. There are few reports of successful treatment of chytridiomycosis and none that include curing amphibians with severe disease. Three terminally ill green tree frogs (Litoria caerulea) with heavy Bd infections were cured using a combination of continuous shallow immersion in 20 mg/L chloramphenicol solution for 14 days, parenteral isotonic electrolyte fluid therapy for 6 days, and increased ambient temperature to 28 degrees C for 14 days. All terminally ill frogs recovered rapidly to normal activity levels and appetite within 5 days of commencing treatment. In contrast, five untreated terminally ill L. caerulea with heavy Bd infections died within 24-48 hr of becoming moribund. Subclinical infections in 15 experimentally infected L. caerulea were cured within 28 days by continuous shallow immersion in 20 mg/L chloramphenicol solution without adverse effects. This is the first known report of a clinical treatment protocol for curing terminally ill Bd-infected frogs.

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

    Directory of Open Access Journals (Sweden)

    Ourania N Kostopoulou

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

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

    Directory of Open Access Journals (Sweden)

    Bayeh Abera

    2014-01-01

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

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

    Science.gov (United States)

    Zhou, Jian; Song, Yinqing; Wang, Tongtong

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Pettigrew, David M.; Roversi, Pietro [Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE (United Kingdom); Davies, Stephen G.; Russell, Angela J. [Department of Chemistry, Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA (United Kingdom); Lea, Susan M., E-mail: susan.lea@path.ox.ac.uk [Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE (United Kingdom)

    2009-06-01

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

  15. Chloramphenicol Derivatives as Antibacterial and Anticancer Agents: Historic Problems and Current Solutions

    Directory of Open Access Journals (Sweden)

    George P. Dinos

    2016-06-01

    Full Text Available Chloramphenicol (CAM is the D-threo isomer of a small molecule, consisting of a p-nitrobenzene ring connected to a dichloroacetyl tail through a 2-amino-1,3-propanediol moiety. CAM displays a broad-spectrum bacteriostatic activity by specifically inhibiting the bacterial protein synthesis. In certain but important cases, it also exhibits bactericidal activity, namely against the three most common causes of meningitis, Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis. Resistance to CAM has been frequently reported and ascribed to a variety of mechanisms. However, the most important concerns that limit its clinical utility relate to side effects such as neurotoxicity and hematologic disorders. In this review, we present previous and current efforts to synthesize CAM derivatives with improved pharmacological properties. In addition, we highlight potentially broader roles of these derivatives in investigating the plasticity of the ribosomal catalytic center, the main target of CAM.

  16. Chloramphenicol Mediates Superoxide Production in Photosystem II and Enhances Its Photodamage in Isolated Membrane Particles

    Science.gov (United States)

    Rehman, Ateeq Ur; Kodru, Sandeesha; Vass, Imre

    2016-01-01

    Chloramphenicol (CAP) is an inhibitor of protein synthesis, which is frequently used to decouple photodamage and protein synthesis dependent repair of Photosystem II during the process of photoinhibition. It has been reported earlier that CAP is able to mediate superoxide production by transferring electrons from the acceptor side of Photosystem I to oxygen. Here we investigated the interaction of CAP with Photosystem II electron transport processes by oxygen uptake and variable chlorophyll fluorescence measurements. Our data show that CAP can accept electrons at the acceptor side of Photosystem II, most likely from Pheophytin, and deliver them to molecular oxygen leading to superoxide production. In addition, the presence of CAP enhances photodamage of Photosystem II electron transport in isolated membrane particles, which effect is reversible by superoxide dismutase. It is concluded that CAP acts as electron acceptor in Photosystem II and mediates its superoxide dependent photodamage. This effect has potential implications for the application of CAP in photoinhibitory studies in intact systems. PMID:27092170

  17. The Identification of Intrinsic Chloramphenicol and Tetracycline Resistance Genes in Members of the Bacillus cereus Group (sensu lato)

    Science.gov (United States)

    Glenwright, Helen; Pohl, Susanne; Navarro, Ferran; Miro, Elisenda; Jiménez, Guillermo; Blanch, Anicet R.; Harwood, Colin R.

    2017-01-01

    Bacillus toyonensis strain BCT-7112T (NCIMB 14858T) has been widely used as an additive in animal nutrition for more than 30 years without reports of adverse toxigenic effects. However, this strain is resistant to chloramphenicol and tetracycline and it is generally considered inadvisable to introduce into the food chain resistance determinants capable of being transferred to other bacterial strains, thereby adding to the pool of such determinants in the gastro-enteric systems of livestock species. We therefore characterized the resistance phenotypes of this strain and its close relatives to determine whether they were of recent origin, and therefore likely to be transmissible. To this end we identified the genes responsible for chloramphenicol (catQ) and tetracycline (tetM) resistance and confirmed the presence of homologs in other members of the B. toyonensis taxonomic unit. Unexpectedly, closely related strains encoding these genes did not exhibit chloramphenicol and tetracycline resistance phenotypes. To understand the differences in the behaviors, we cloned and expressed the genes, together with their upstream regulatory regions, into Bacillus subtilis. The data showed that the genes encoded functional proteins, but were expressed inefficiently from their native promoters. B. toyonensis is a taxonomic unit member of the Bacillus cereus group (sensu lato). We therefore extended the analysis to determine the extent to which homologous chloramphenicol and tetracycline resistance genes were present in other species within this group. This analysis revealed that homologous genes were present in nearly all representative species within the B. cereus group (sensu lato). The absence of known transposition elements and the observations that they are found at the same genomic locations, indicates that these chloramphenicol and tetracycline resistance genes are of ancient origin and intrinsic to this taxonomic group, rather than recent acquisitions. In this context we

  18. The Identification of Intrinsic Chloramphenicol and Tetracycline Resistance Genes in Members of the Bacillus cereus Group (sensu lato).

    Science.gov (United States)

    Glenwright, Helen; Pohl, Susanne; Navarro, Ferran; Miro, Elisenda; Jiménez, Guillermo; Blanch, Anicet R; Harwood, Colin R

    2016-01-01

    Bacillus toyonensis strain BCT-7112(T) (NCIMB 14858(T)) has been widely used as an additive in animal nutrition for more than 30 years without reports of adverse toxigenic effects. However, this strain is resistant to chloramphenicol and tetracycline and it is generally considered inadvisable to introduce into the food chain resistance determinants capable of being transferred to other bacterial strains, thereby adding to the pool of such determinants in the gastro-enteric systems of livestock species. We therefore characterized the resistance phenotypes of this strain and its close relatives to determine whether they were of recent origin, and therefore likely to be transmissible. To this end we identified the genes responsible for chloramphenicol (catQ) and tetracycline (tetM) resistance and confirmed the presence of homologs in other members of the B. toyonensis taxonomic unit. Unexpectedly, closely related strains encoding these genes did not exhibit chloramphenicol and tetracycline resistance phenotypes. To understand the differences in the behaviors, we cloned and expressed the genes, together with their upstream regulatory regions, into Bacillus subtilis. The data showed that the genes encoded functional proteins, but were expressed inefficiently from their native promoters. B. toyonensis is a taxonomic unit member of the Bacillus cereus group (sensu lato). We therefore extended the analysis to determine the extent to which homologous chloramphenicol and tetracycline resistance genes were present in other species within this group. This analysis revealed that homologous genes were present in nearly all representative species within the B. cereus group (sensu lato). The absence of known transposition elements and the observations that they are found at the same genomic locations, indicates that these chloramphenicol and tetracycline resistance genes are of ancient origin and intrinsic to this taxonomic group, rather than recent acquisitions. In this context

  19. Quantitative trace analysis of eight chloramphenicol isomers in urine by chiral liquid chromatography coupled to tandem mass spectrometry.

    Science.gov (United States)

    Berendsen, Bjorn J A; Essers, Martien L; Stolker, Linda A A M; Nielen, Michel W F

    2011-10-14

    Chloramphenicol is a broad-spectrum antibiotic with, apart from its human medicinal use, veterinary abuse in all major food-producing animals. Chloramphenicol occurs in four stereoisomers (all para-nitro substituted) and furthermore four meta-nitro analogs of chloramphenicol exist. In this paper these are referred to as eight chloramphenicol isomers. According to EU regulations an analytical method should be able to discriminate the analyte from interfering substances that might be present in the sample, including isomers. For the first time a quantitative method for the analysis of trace levels of eight chloramphenicol isomers in urine by chiral liquid chromatography in combination with tandem mass spectrometric detection is reported. The separation of the isomers on the analytical column, the clean-up of urine and the selectivity of the monitored product ions turned out to be critical parameters. To obtain reproducible retention isocratic elution on a chiral AGP column was applied. For urine samples matrix compounds present in the final extract caused decreased retention of the isomers on the chiral stationary phase and a lack of chromatographic resolution. Therefore an extended clean-up procedure that combines solid phase extraction and liquid-liquid extraction had to be developed. The final method was fully validated and showed satisfactory performance for all isomers with decision limits (CCα) ranging from 0.005 to 0.03 μg L(-1) and within-laboratory reproducibility of all isomers below 20% at the minimum required performance limit level of 0.3 μg L(-1).

  20. Simultaneous determination of chloramphenicol, florfenicol and florfenicol amine in ham sausage with a hybrid chemiluminescent immunoassay.

    Science.gov (United States)

    Tao, Xiaoqi; Jiang, Haiyang; Yu, Xuezhi; Zhu, Jinghui; Wang, Xia; Wang, Zhanhui; Niu, Lanlan; Wu, Xiaoping; Shen, Jianzhong

    2013-01-01

    A novel chemiluminescent immunoassay utilising two types of primary antibodies (murine monoclonal antibody and rabbit polyclonal antibody) and two types of horseradish peroxidase-labelled secondary antibodies was established for simultaneously detecting multiple amphenicol residues in ham sausage. After combining the extract procedure of the target amphenicol into one simplified method, this hybrid chemiluminescent immunoassay could screen chloramphenicol (CAP), florfenicol (FF) and its metabolite florfenicol amine (FFA) at the same time by adding the corresponding secondary antibody. Ham sausage samples were analysed by using this hybrid immunoassay, with LODs of CAP being 0.01 μg kg⁻¹, of FF being 2.8 μg kg⁻¹ and of FFA being 3.0 μg kg⁻¹. The applicability of the proposed method has been validated by determining CAP, FF and FFA in ham sausage samples with satisfactory results. Good recoveries and high correlation with traditional enzyme-linked immunosorbent assay and LC-MS/MS results illustrated that the developed hybrid chemiluminescent immunoassay could screen high-throughput ultra-trace amphenicol residues effectively at one time.

  1. Modification by chloramphenicol of diethyl sulphate-induced male recombination frequency in Drosophila melanogaster.

    Science.gov (United States)

    Miglani, G S; Kaur, N P

    1995-06-01

    To study the effect of chloramphenicol (CPL, an inhibitor of protein synthesis) on diethyl sulphate (DES, a potent mutagen) induced male recombination frequency, the F1 (+/aristaless dumpy black cinnabar, al dp b cn) larvae of D. melanogaster were given a pre- or post-treatment of CPL with DES during the first or second half of larval life. In order to determine sensitivity of different germ cell stages to the induction and modification of male recombination frequency, five 3-day broods were taken from every F1 male. DES showed toxic effect on egg-to-adult development. DES was found to be a potent recombinogen. Several cases of non-reciprocal male recombination were recorded. The most frequent recombinant phenotype observed was b cn followed by cn and al. Majority of the recombinants appeared in clusters suggesting their pre-meiotic origin. DES produced male recombination at a stage where only primary spermatocytes were present in the larval testes. CPL when given as a pre- or post-treatment with DES revealed highest frequency of male recombination in broods that represented effect of treatment on spermatogonia predominantly. CPL enhanced the overall level of male recombination produced by DES in both pre- and post-treatments. The results suggested the role of protein synthesis in induction of male recombination in D. melanogaster. In addition, the present experiments give a methodology of enhancing the frequency of chemically-induced male recombination.

  2. Highly sensitive electrochemical sensor for chloramphenicol based on MOF derived exfoliated porous carbon.

    Science.gov (United States)

    Xiao, Lili; Xu, Ruiyu; Yuan, Qunhui; Wang, Fu

    2017-05-15

    Benefit from the advantages in costless, simplicity and efficiency, solvent exfoliation has been widely used in preparation of two-dimensional nanosheets with enhanced performances in electronics, photonics, and catalysis. In this work, solvent exfoliation was first applied to prepare exfoliated porous carbon (EPC) from an isoreticular metal-organic framework-8 (IRMOF-8) derived porous carbon (DPC). The obtained EPC with high surface area (1854m(2)g(-1)) and improved dispersibility was used as electrode modifier for glassy carbon electrode (GCE) in square wave voltammetry (SWV) detection of chloramphenicol (CAP). The sensitivity of EPC modified GCE (EPC/GCE) was greatly improved in compare with that of the DPC modification. The corresponding linear ranges are 1×10(-8)-1×10(-6)molL(-1) and 1×10(-6)-4×10(-6)molL(-1). The detection limit was calculated to be 2.9×10(-9)molL(-1) (at a signal-to-noise ratio of 3, S/N=3). In addition, the proposed sensor was successfully applied in the analysis of CAP in honey and achieved satisfying recovery.

  3. Hydrolysis of amphenicol and macrolide antibiotics: Chloramphenicol, florfenicol, spiramycin, and tylosin.

    Science.gov (United States)

    Mitchell, Shannon M; Ullman, Jeffrey L; Teel, Amy L; Watts, Richard J

    2015-09-01

    Antibiotics that enter the environment can present human and ecological health risks. An understanding of antibiotic hydrolysis rates is important for predicting their environmental persistence as biologically active contaminants. In this study, hydrolysis rates and Arrhenius constants were determined as a function of pH and temperature for two amphenicol (chloramphenicol and florfenicol) and two macrolide (spiramycin and tylosin) antibiotics. Antibiotic hydrolysis rates in pH 4-9 buffer solutions at 25°C, 50°C, and 60°C were quantified, and degradation products were characterized. All of the antibiotics tested remained stable and exhibited no observable hydrolysis under ambient conditions typical of aquatic ecosystems. Acid- and base-catalyzed hydrolysis occurred at elevated temperatures (50-60°C), and hydrolysis rates increased considerably below pH 5 and above pH 8. Hydrolysis rates also increased approximately 1.5- to 2.9-fold for each 10°C increase in temperature. Based on the degradation product masses found, the functional groups that underwent hydrolysis were alkyl fluoride, amide, and cyclic ester (lactone) moieties; some of the resultant degradation products may remain bioactive, but to a lesser extent than the parent compounds. The results of this research demonstrate that amphenicol and macrolide antibiotics persist in aquatic systems under ambient temperature and pH conditions typical of natural waters. Thus, these antibiotics may present a risk in aquatic ecosystems depending on the concentration present.

  4. Synthesis of Chloramphenicol artificial antigen%氯霉素人工抗原的合成

    Institute of Scientific and Technical Information of China (English)

    邢淑婕; 徐固华; 王琴

    2007-01-01

    以重氮化法分别将氯霉素(chloramphenicol,CAP)与牛血清白蛋白(bovine serum albumin,BSA)及卵清白蛋白(ovaibumin,OVA)进行偶联,得到复合物CAP-BSA和CAP-OVA.对复合物紫外扫描显示其扫描谱图与BSA和氯霉素的图谱有明显的差异,BSA及OV与氯霉素偶联成功.分析CAP-BSA中CAP与BSA的摩尔比,偶联时,CAP与BSA的起始质量比为1:1、1:2、2:1时,偶联物中CAP:BSA摩尔比分别为4.69:1、8.90:1、7.94:1,说明反应起始时不同的CAP与蛋白质配比会对偶联效果有较大的影响.以摩尔比为8.90:1的CAP-BSA免疫BALB/c小鼠65d后,间接ELISA检测测定效价达1:20000.

  5. Monitoring of Leuconostoc mesenteroides DRC starter in fermented vegetable by random integration of chloramphenicol acetyltransferase gene.

    Science.gov (United States)

    Eom, Hyun-Ju; Park, Joong Min; Seo, Min Jae; Kim, Myoung-Dong; Han, Nam Soo

    2008-09-01

    In 2004, Leuconostoc mesenteroides DRC was first used as a starter culture for achieving higher organoleptic effects in Korean kimchi manufacture. For a better understanding of starter growth in a mixed culture system, and for predicting starter predominance in kimchi, a monitoring system for the starter was established. The chloramphenicol resistance marker gene (cat) was randomly integrated into chromosomal DNA of L. mesenteroides DRC using a viral transposon and transposase. The DRC mutant, tDRC2, had a similar growth pattern to the host strain, with no major alteration in phenotypic characteristics. The mutant strain was inoculated into real kimchi, and monitoring of the starter population was successfully achieved. The overall predominance of Leuconostoc in kimchi inoculated with DRC followed the general growth pattern of this genus during kimchi fermentation. Our results also demonstrate the competitive ability of the DRC starter against Leuconostoc from natural flora, maintaining its predominance above 88% during the whole fermentation period. Based on this experiment, the random gene integration method using a transposon was shown to be of utility in transferring any commercial starter into a selectable and monitorable strain for simulation purposes.

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

    Science.gov (United States)

    Peach, C; Velten, J

    1992-02-01

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

  7. A gel-based visual immunoassay for non-instrumental detection of chloramphenicol in food samples.

    Science.gov (United States)

    Yuan, Meng; Sheng, Wei; Zhang, Yan; Wang, Junping; Yang, Yijin; Zhang, Shuguang; Goryacheva, Irina Yu; Wang, Shuo

    2012-11-01

    A gel-based non-instrumental immuno-affinity assay was developed for the rapid screening of chloramphenicol (CAP) in food samples with the limit of detection (LOD) of 1 μg L(-1). The immuno-affinity test column (IATC) consisted of a test layer containing anti-CAP antibody coupled gel, and a control layer with anti-HRP antibody coupled gel. Based on the direct competitive immuno-reaction and the horseradish peroxidase enzymatic reaction, the test results could be evaluated visually. Basically, blue color development represented the negative results, while the absence of color development represented the positive results. In this study, CAP spiked samples of raw milk, pasteurized milk, UHT milk, skimmed milk powder, acacia honey, date honey, fish and shrimp were tested. Little or none sample pretreatment was required for this assay. The whole procedure was completed within 10min. In conclusion, the gel-based immuno-affinity test is a simple, rapid, and promising on-site screening method for CAP residues in food samples, with no instrumental requirement.

  8. Elimination of chloramphenicol, sulphamethoxazole and oxytetracycline in shrimp, Penaeus chinensis following medicated-feed treatment.

    Science.gov (United States)

    Wang, Weifen; Lin, Hong; Xue, Changhu; Khalid, Jamil

    2004-05-01

    Muscle residue depletion of chloramphenicol (CAP), sulphamethoxazole (SMZ) and oxytetracycline (OTC) following oral administration was evaluated in shrimp, Penaeus chinensis under field conditions. Three groups of shrimps were cultured in tanks filled with seawater and fed a commercial medicated diet containing 2000 mg kg(-1) CAP, SMZ and OTC, respectively, twice daily for 3 days. Sampling was conducted at different intervals (0, 0.5, 1, 1.5, 2, 3, 4, 8, 10, 12, 16, 24, 36, 48, 72, 96, 120, 144, 168 h) after the cessation of medication. Drug analysis was carried out by HPLC. The elimination half-life (t(1/2)) of CAP was 10.04 h, the elimination half-life (t(1/2)) of SMZ was 5.68 h and that of OTC was 16.12 h. If the EU MRPL value of 0.3 ng/g for CAP and MRL value of 0.1 microg/g for SMZ and OTC quoted for muscle from finfish is extended to shrimp muscle, extrapolation of the data indicates that it would be passed after a 139.7 h (95% CI=132.0-144.4 h), 30.6 h (95% CI=27.2-33.1 h), 90.3 h (95% CI=87.9-92.5 h) withdrawal period for CAP, SMZ and OTC in shrimp muscle, respectively.

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

    Directory of Open Access Journals (Sweden)

    Neethu Hari

    2014-01-01

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

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

    Science.gov (United States)

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

    2016-06-05

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-06-15

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

  12. Comparative efficacy of oral rifampin and topical chloramphenicol in eradicating conjunctival carriage of Haemophilus influenzae biogroup aegyptius. Brazilian Purpuric Fever Study Group.

    Science.gov (United States)

    Perkins, B A; Tondella, M L; Bortolotto, I M; Takano, O A; da Silva, G A; Irino, K; Brandileone, M C; Harrison, L H; Wenger, J D; Broome, C V

    1992-09-01

    Persistent conjunctival carriage of the Haemophilus influenzae biogroup aegyptius (Hae) strain (BPF clone) responsible for Brazilian purpuric fever (BPF) has been documented. Topical chloramphenicol is routinely used to treat conjunctivitis in areas affected by BPF in Brazil. Although the BPF clone is susceptible to chloramphenicol, we observed a number of children treated with topical chloramphenicol for conjunctivitis who still developed BPF. During an investigation of an outbreak of BPF in Mato Grosso State, Brazil, we compared oral rifampin (20 mg/kg/day for 4 days) with topical chloramphenicol for eradication of conjunctival carriage of H. influenzae biogroup aegyptius among children with presumed BPF clone conjunctivitis. Conjunctival samples were taken for culture on the day treatment was initiated and a mean of 8 and 21 days later. At 8 days the eradication rates for oral rifampin and topical chloramphenicol were 100 and 44%, respectively (P = 0.003); at 21 days they were 100 and 50% (P = 0.01). Oral rifampin was more effective than topical chloramphenicol for eradication of the BPF clone and may be useful in prevention of BPF.

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

    Directory of Open Access Journals (Sweden)

    Widiastuti R

    2014-03-01

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

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

    Directory of Open Access Journals (Sweden)

    Bošnir, J.

    2007-02-01

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

  15. Determination of chloramphenicol residues in commercial chicken eggs in the Federal Capital Territory, Abuja, Nigeria.

    Science.gov (United States)

    Mbodi, Felix E; Nguku, P; Okolocha, E; Kabir, J

    2014-01-01

    The use of antibiotics in poultry can result in residues in eggs. The joint FAO/WHO committee recommended banning the use of chloramphenicol (CAP) in food animals due to its public health hazards of aplastic anaemia, leukaemia, allergy, antibacterial resistance and carcinogenicity. This paper determines the prevalence of CAP residues in chicken eggs and assesses the usage and awareness of its ban amongst poultry farmers in the Federal Capital Territory (FCT), Abuja, Nigeria. A cross-sectional survey of registered poultry farmers in FCT was conducted using questionnaires to determine CAP administration in poultry and awareness of its ban. Pooled egg samples were collected from each poultry farm surveyed and from randomly sampled government-owned markets in FCT. Source of eggs by state were identified by the marketer at the time of collection. Samples were analysed using an enzyme-linked immunosorbent assay (ELISA) technique for the presence of CAP, and prevalence was determined. Of 288 total pooled samples collected, 257 (89.2%) were from the markets and 31 (10.8%) were from poultry farms. A total of 20 (7%) pooled egg samples tested CAP-positive; market eggs originated from 15 (41%) states of the country. Of the market eggs, 16 (6.2%) pooled samples tested positive. Of eggs from poultry farms, four (12.9%) tested positive. Mean CAP concentrations in the positive samples ranged from 0.49 to 1.17 µg kg(-1) (parts per billion). CAP use amongst poultry farmers in FCT was 75.5%; awareness of the CAP ban was 26.3%. Though 66% of veterinarians were unaware of a CAP ban, they were more likely to be aware than other poultry farmers (odds ratio (OR) = 1.4). Farm managers who use CAP were more likely to be aware of CAP ban than the farm managers not using CAP (OR = 5.5; p = 0.04). Establishing a drug residue surveillance and control program and enforcement of CAP legislation/regulation is needful to educate and prohibit the widespread CAP use amongst Nigerian poultry farmers.

  16. Changes in behavior and hematological parameters of freshwater African catfish Clarias gariepinus (Burchell 1822) following sublethal exposure to chloramphenicol.

    Science.gov (United States)

    Nwani, Christopher Didigwu; Mkpadobi, Blessing Nonye; Onyishi, Grace; Echi, Paul Chinedu; Chukwuka, Christian Onyeka; Oluah, Stanley Ndubuisi; Ivoke, Njoku

    2014-01-01

    The present study was aimed at evaluating the effects of different concentrations of the most commonly used fish antimicrobial drug, chloramphenicol (CAP), on the behavior and hematological parameters of Clarias gariepinus. Fish specimens were exposed to three (2.5, 5.0 and 10.0 mg L(-1)) sublethal concentrations of CAP and a control. Abnormal behavioral changes were observed in fish exposed to higher concentration of CAP. Blood erythrocytes were sampled on days 1, 5, 10 and 15 postexposure to evaluate hematological parameters. Results showed concentration- and time-dependent significant increase in packed cell volume after day 5 of exposure (p gariepinus in aquaculture.

  17. Determination of chloramphenicol residue in fish and shrimp tissues by gas chromatography with a microcell electron capture detector.

    Science.gov (United States)

    Ding, Shuangyang; Shen, Jianzhong; Zhang, Suxia; Jiang, Haiyang; Sun, Zhiwen

    2005-01-01

    A gas chromatography method with microcell electron capture detection was developed for the determination of chloramphenicol residue in fish and shrimp muscle tissues. The tissue samples were extracted with ethyl acetate, defatted with hexane, and derivatized with Sylon BFT [N,O-bis (trimethylsilyl) trifluoroacetamide-trimethylchlorosilane (99 + 1)]. The limit of detection was 0.04 ng/g and the limit of quantitation 0.1 ng/g. Average recoveries were 70.8-90.8% for fish and 69.9-86.3% for shrimp, respectively. The method was validated for the determination of practical samples.

  18. A simple sample preparation for simultaneous determination of chloramphenicol and its succinate esters in food products using high-performance liquid chromatography/high-resolution mass spectrometry.

    Science.gov (United States)

    Amelin, Vasiliy; Korotkov, Anton

    2017-02-01

    A simple method is described for the determination of chloramphenicol and its succinate esters in food products. Examination of food products using high-performance liquid chromatography/high-resolution mass spectrometry showed the presence not only of chloramphenicol but also of its succinate forms. A scheme is proposed for determining chloramphenicol and its succinate esters (calculated as chloramphenicol) in meat (beef, pork, poultry), milk, liver, kidney, eggs, fish and honey. Analytes are extracted from a 1.0 g sample with 5 ml acetonitrile. It was found that using the method of standard addition and diluting the extract with water leads to the elimination of matrix effects and also eliminates errors associated with peak splitting due to the separate elution of the differing forms of the analyte. Validation results were satisfactory, with recoveries from 85% to 111% (meat, milk, liver, kidney, eggs, fish and honey) and a relative standard deviation (RSD) lower than 13% for spiked levels of 0.3, 1.0 and 5 µg kg(-)(1). The limits of detection and quantification (calculated as chloramphenicol for all forms) were 0.1 and 0.3 µg kg(-)(1), respectively. The RSD of the results of the analysis was < 10%. The duration of the analysis was less than 1 h.

  19. Synthesis, spectroscopic, thermal and anticancer studies of metal-antibiotic chelations: Ca(II), Fe(III), Pd(II) and Au(III) chloramphenicol complexes

    Science.gov (United States)

    Al-Khodir, Fatima A. I.; Refat, Moamen S.

    2016-09-01

    Four Ca(II), Fe(III), Pd(II) and Au(III) complexes of chloramphenicol drug have been synthesized and well characterized using elemental analyses, (infrared, electronic, and 1H-NMR) spectra, magnetic susceptibility measurement, and thermal analyses. Infrared spectral data show that the chloramphenicol drug coordinated to Ca(II), Pd(II) and Au(III) metal ions through two hydroxyl groups with 1:1 or 1:2 M ratios, but Fe(III) ions chelated towards chloramphenicol drug via the oxygen and nitrogen atoms of amide group with 1:2 ratio based on presence of keto↔enol form. The X-ray powder diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) techniques were used to identify the nano-size particles of both iron(III) and gold(III) chloramphenicol complexes. The antimicrobial assessments of the chloramphenicol complexes were scanned and collected the results against of some kind of bacteria and fungi. The cytotoxic activity of the gold(III) complex was tested against the human colon carcinoma (HCT-116) and human hepatocellular carcinoma (HepG-2) tumor cell lines.

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

    Directory of Open Access Journals (Sweden)

    Musharraf Syed

    2012-01-01

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

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

    Science.gov (United States)

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

    2016-08-01

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

  2. Characterization of the myelotoxicity of chloramphenicol succinate in the B6C3F1 mouse.

    Science.gov (United States)

    Turton, John A; Fagg, Rajni; Sones, William R; Williams, Thomas C; Andrews, C Michael

    2006-04-01

    Chloramphenicol (CAP) is haemotoxic in man, inducing two types of toxicity. First, a dose-related, reversible anaemia with reticulocytopenia, sometimes seen in conjunction with leucopenia and thrombocytopenia; this form of toxicity develops during drug treatment. The second haemotoxicity is aplastic anaemia (AA) which is evident in the blood as severe pancytopenia. AA development is not dose-related and occurs weeks or months after treatment. We wish, in the longer term, to investigate CAP-induced AA in the busulphan-pretreated mouse. However, as a prelude to that study, we wanted to characterize in detail the reversible haemotoxicity of CAP succinate (CAPS), administered at high dose levels in the mouse, and follow the recovery of the bone marrow in the post-dosing period. Female B6C3F1 mice were gavaged with CAPS at 0, 2500 and 3500 mg/kg, daily, for 5 days and sampled (n = 5) at 1, 7, 14 and 21 days post-dosing. Blood, bone marrow and spleen samples were analysed and clonogenic assays carried out. At day 1 post-dosing, at both CAPS dose levels, decreases were seen in erythrocytes and erythrocyte precursors; marrow erythroid cells were reduced. Reductions were also evident in splenic nucleated cell counts, blood high fluorescence ratio (HFR) reticulocyte counts and total reticulocyte counts; burst-forming units-erythroid and colony-forming units-erythroid showed decreases. At day 7 post-dosing (2500 mg/kg CAPS), there was regeneration of erythrocyte production, with marked splenic erythropoietic activity, and raised blood HFR reticulocytes. At day 7, at 3500 mg/kg CAPS, erythrocyte and reticulocyte parameters remained depressed. At 14 days post-dosing (2500 mg/kg CAPS), many erythrocyte parameters had returned to normal; at 3500 mg/kg CAPS, there was erythroid regeneration. By 21 days post-dosing, at both CAPS dose levels, most erythrocytic parameters were equivalent to control values. For leucocyte parameters, there was some depression at day 1 post-dosing (at

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

    DEFF Research Database (Denmark)

    Vester, Birte; Garrett, Roger Antony

    1988-01-01

    The peptidyl transfer site has been localized at the centre of domain V of 23S-like ribosomal RNA (rRNA) primarily on the basis of a chloramphenicol binding site. The implicated region constitutes an unstructured circle in the current secondary structural model which contains several universally...... into 50S subunits, but while the two lethal mutant RNAs were strongly selected against in 70S ribosomes, the plasmid-encoded A2503----C RNA was preferred over the chromosome-encoded RNA, contrary to current regulatory theories. The results establish the critical structural and functional importance...... of highly conserved nucleotides in the chloramphenicol binding region. A mechanistic model is also presented to explain the disruptive effect of chloramphenicol (and other antibiotics) on peptide bond formation at the ribosomal subunit interface....

  4. Removal of chloramphenicol by macroporous adsorption resins in honey: a novel approach on reutilization of antibiotics contaminated honey.

    Science.gov (United States)

    Cheng, Ni; Gao, Hui; Deng, Jianjun; Wang, Bini; Xu, Ruihan; Cao, Wei

    2012-09-01

    The effects of different steps in honey production on chloramphenicol (CAP) levels and CAP removal from honey using macroporous adsorption resins (MARs) were investigated in this study. CAP residues in honey were quantified by enzyme-linked immunosorbent assay after each processing step including preheating, filtration, vacuum concentration and pasteurization. Vacuum concentration contributes the most reduction of CAP level (9.9%). Meanwhile, 5 types of MARs (including LSI-1, LSI-2, LSI-3, LS-803, and LS-903) were used in CAP adsorption. The results showed that LS-803 resin had higher adsorption rate of 86% than other resins in removing CAP from honey, and its optimal adsorption time and temperature were 40 min and 55 °C, respectively. The treated honey could be used as feed additive or biomass energy. Therefore, it would be a novel approach to reutilization of antibiotics contaminated honey.

  5. Multilaboratory validation of a method to confirm chloramphenicol in shrimp and crabmeat by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Hammack, Walter; Carson, Mary C; Neuhaus, Barbara K; Hurlbut, Jeffrey A; Nochetto, Cristina; Stuart, James S; Brown, Amy; Kilpatrick, Donna; Youngs, Kristl; Ferbos, Krystle; Heller, David N

    2003-01-01

    An existing method for chloramphenicol (CAP) determination in shrimp using a gas chromatograph with electron capture detector was adapted for confirmation of CAP with a liquid chromatograph interfaced to a triple quadrupole mass spectrometer. CAP residues are extracted from tissue with ethyl acetate, isolated via liquid-liquid extraction, and concentrated by evaporation. Extracts are chromatographed by using a reversed-phased column and analyzed by electrospray negative mode tandem mass spectrometry. Four product ions (m/z 152, 176, 194, and 257) of precursor m/z 321 were monitored. Moving from gas chromatography to liquid chromatography-tandem mass spectrometry improved the sensitivity of the method greatly, enabling reliable confirmation of CAP residues at 0.3 microg/kg (ppb). The method meets confirmation criteria recommended by the U.S. Food and Drug Administration and 4-point identification criteria established by the European Union. With slight modifications to accommodate different equipment, the method was validated in 3 laboratories.

  6. Antibiogram of Salmonella Isolates from Blood with an Emphasis on Nalidixic Acid and Chloramphenicol Susceptibility in a Tertiary Care Hospital in Coastal Karnataka: A Prospective Study

    Directory of Open Access Journals (Sweden)

    Anup Kumar Shetty

    2012-01-01

    Conclusion: Routine screening of Nalidixic acid susceptibility is practical to predict fluorquinolone resistance in Salmonella and preventing therapeutic failure while treating with it. It is worthwhile to consider replacing fluorquinolones with Chloramphenicol or Ceftriaxone as the first line of therapy for enteric fever. Periodic analysis of Salmonella antibiogram should be done to formulate the best possible treatment strategies.

  7. Determination of chloramphenicol in bovine urine, meat and shrimp by GC-MS. Method validation according to Commission Decision 2002/657/EC

    NARCIS (Netherlands)

    Rossum HJ van; Kootstra PR; Sterk SS; ARO

    2004-01-01

    This report describes the validation of the quantification and the identification of an analytical method for the determination of low concentrations (0.1-1.0 micro g/kg) of chloramphenicol in samples of urine, shrimps and meat. The validation study was based on the criteria described in Decision 20

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

    Directory of Open Access Journals (Sweden)

    M. Jakiul Islam

    2014-11-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-01-07

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

  10. Cometabolic degradation of chloramphenicol via a meta-cleavage pathway in a microbial fuel cell and its microbial community.

    Science.gov (United States)

    Zhang, Qinghua; Zhang, Yanyan; Li, Daping

    2017-04-01

    The performance of a microbial fuel cell (MFC) in terms of degradation of chloramphenicol (CAP) was investigated. Approximately 84% of 50mg/L CAP was degraded within 12h in the MFC. A significant interaction of pH, temperature, and initial CAP concentration was found on removal of CAP, and a maximum degradation rate of 96.53% could theoretically be achieved at 31.48°C, a pH of 7.12, and an initial CAP concentration of 106.37mg/L. Moreover, CAP was further degraded through a ring-cleavage pathway. The antibacterial activity of CAP towards Escherichia coli ATCC 25922 and Shewanella oneidensis MR-1 was largely eliminated by MFC treatment. High-throughput sequencing analysis indicated that Azonexus, Comamonas, Nitrososphaera, Chryseobacterium, Azoarcus, Rhodococcus, and Dysgonomonas were the predominant genera in the MFC anode biofilm. In conclusion, the MFC shows potential for the treatment of antibiotic residue-containing wastewater due to its high rates of CAP removal and energy recovery.

  11. Development of an Immunoassay for Chloramphenicol Based on the Preparation of a Specific Single-Chain Variable Fragment Antibody.

    Science.gov (United States)

    Du, Xin-jun; Zhou, Xiao-nan; Li, Ping; Sheng, Wei; Ducancel, Frédéric; Wang, Shuo

    2016-04-13

    Specific antibodies are essential for the immune detection of small molecule contaminants. In the present study, the heavy and light variable regions (V(H )and V(L)) of the immunoglobulin genes from a hybridoma secreting a chloramphenicol (CAP)-specific monoclonal antibody (mAb) were cloned and sequenced. In addition, the light and heavy chains obtained from the monoclonal antibody were separated using SDS-PAGE and analyzed using Orbitrap mass spectrometry. The results of DNA sequencing and mass spectrometry analysis were compared, and the V(H) and V(L) chains specific for CAP were determined and used to construct a single-chain variable fragment (scFv). This fragment was recombinantly expressed as a soluble scFv-alkaline phosphatase fusion protein and used to develop a direct competitive ELISA. Compared with the parent mAb, scFv exhibits lower sensitivity but better food matrix resistance. This work highlights the application of engineered antibodies for CAP detection.

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

    Science.gov (United States)

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

    2016-05-01

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

  13. Monitoring bacterial resistance to chloramphenicol and other antibiotics by liquid chromatography electrospray ionization tandem mass spectrometry using selected reaction monitoring.

    Science.gov (United States)

    Haag, Anthony M; Medina, Audrie M; Royall, Ariel E; Herzog, Norbert K; Niesel, David W

    2013-06-01

    Antibiotic resistance is a growing problem worldwide. For this reason, clinical laboratories often determine the susceptibility of the bacterial isolate to a number of different antibiotics in order to establish the most effective antibiotic for treatment. Unfortunately, current susceptibility assays are time consuming. Antibiotic resistance often involves the chemical modification of an antibiotic to an inactive form by an enzyme expressed by the bacterium. Selected reaction monitoring (SRM) has the ability to quickly monitor and identify these chemical changes in an unprecedented time scale. In this work, we used SRM as a technique to determine the susceptibility of several different antibiotics to the chemically modifying enzymes β-lactamase and chloramphenicol acetyltransferase, enzymes used by bacteria to confer resistance to major classes of commonly used antibiotics. We also used this technique to directly monitor the effects of resistant bacteria grown in a broth containing a specific antibiotic. Because SRM is highly selective and can also identify chemical changes in a multitude of antibiotics in a single assay, SRM has the ability to detect organisms that are resistant to multiple antibiotics in a single assay. For these reasons, the use of SRM greatly reduces the time it takes to determine the susceptibility or resistance of an organism to a multitude of antibiotics by eliminating the time-consuming process found in other currently used methods.

  14. Degradation and antibiotic activity reduction of chloramphenicol in aqueous solution by UV/H2O2 process.

    Science.gov (United States)

    Zuorro, Antonio; Fidaleo, Marco; Fidaleo, Marcello; Lavecchia, Roberto

    2014-01-15

    The efficacy of the UV/H2O2 process to degrade the antibiotic chloramphenicol (CHL) was investigated at 20 °C using a low-pressure mercury lamp as UV source. A preliminary analysis of CHL degradation showed that the process followed apparent first-order kinetics and that an optimum H2O2 concentration existed for the degradation rate. The first-order rate constant was used as the response variable and its dependence on initial CHL and H2O2 concentrations, UV light intensity and reaction time was investigated by a central composite design based on the response surface methodology. Analysis of response surface plots revealed a large positive effect of radiation intensity, a negative effect of CHL concentration and that there was a region of H2O2 concentration leading to maximum CHL degradation. CHL solutions submitted to the UV/H2O2 process were characterized by TOC and their activity against Escherichia coli and Staphylococcus aureus was assessed. No residual antibiotic activity was detected, even at CHL concentrations higher than those used in the designed experiments. Overall, the obtained results strongly support the possibility of reducing the risks associated with the release of CHL into the environment, including the spread of antibiotic resistance, by the UV/H2O2 process.

  15. Contribution of the Antibiotic Chloramphenicol and Its Analogues as Precursors of Dichloroacetamide and Other Disinfection Byproducts in Drinking Water.

    Science.gov (United States)

    Chu, Wenhai; Krasner, Stuart W; Gao, Naiyun; Templeton, Michael R; Yin, Daqiang

    2016-01-01

    Dichloroacetamide (DCAcAm), a disinfection byproduct, has been detected in drinking water. Previous research showed that amino acids may be DCAcAm precursors. However, other precursors may be present. This study explored the contribution of the antibiotic chloramphenicol (CAP) and two of its analogues (thiamphenicol, TAP; florfenicol, FF) (referred to collectively as CAPs), which occur in wastewater-impacted source waters, to the formation of DCAcAm. Their formation yields were compared to free and combined amino acids, and they were investigated in filtered waters from drinking-water-treatment plants, heavily wastewater-impacted natural waters, and secondary effluents from wastewater treatment plants. CAPs had greater DCAcAm formation potential than two representative amino acid precursors. However, in drinking waters with ng/L levels of CAPs, they will not contribute as much to DCAcAm formation as the μg/L levels of amino acids. Also, the effect of advanced oxidation processes (AOPs) on DCAcAm formation from CAPs in real water samples during subsequent chlorination was evaluated. Preoxidation of CAPs with AOPs reduced the formation of DCAcAm during postchlorination. The results of this study suggest that CAPs should be considered as possible precursors of DCAcAm, especially in heavily wastewater-impacted waters.

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

    Science.gov (United States)

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

    2016-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-05-15

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

  18. Transcription factor CecR (YbiH) regulates a set of genes affecting the sensitivity of Escherichia coli against cefoperazone and chloramphenicol.

    Science.gov (United States)

    Yamanaka, Yuki; Shimada, Tomohiro; Yamamoto, Kaneyoshi; Ishihama, Akira

    2016-07-01

    Genomic SELEX (systematic evolution of ligands by exponential enrichment) screening was performed for identification of the binding site of YbiH, an as yet uncharacterized TetR-family transcription factor, on the Escherichia coli genome. YbiH was found to be a unique single-target regulator that binds in vitro within the intergenic spacer located between the divergently transcribed ybiH-ybhGFSR and rhlE operons. YbhG is an inner membrane protein and YbhFSR forms a membrane-associated ATP-binding cassette (ABC) transporter while RhlE is a ribosome-associated RNA helicase. Gel shift assay and DNase footprinting analyses indicated one clear binding site of YbiH, including a complete palindromic sequence of AATTAGTT-AACTAATT. An in vivo reporter assay indicated repression of the ybiH operon and activation of the rhlE operon by YbiH. After phenotype microarray screening, YbiH was indicated to confer resistance to chloramphenicol and cefazoline (a first-generation cephalosporin). A systematic survey of the participation of each of the predicted YbiH-regulated genes in the antibiotic sensitivity indicated involvement of the YbhFSR ABC-type transporter in the sensitivity to cefoperazone (a third-generation cephalosporin) and of the membrane protein YbhG in the control of sensitivity to chloramphenicol. Taken together with the growth test in the presence of these two antibiotics and in vitro transcription assay, it was concluded that the hitherto uncharacterized YbiH regulates transcription of both the bidirectional transcription units, the ybiH-ybhGFSR operon and the rhlE gene, which altogether are involved in the control of sensitivity to cefoperazone and chloramphenicol. We thus propose to rename YbiH as CecR (regulator of cefoperazone and chloramphenicol sensitivity).

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

    Institute of Scientific and Technical Information of China (English)

    孙情; 王宝维; 张乐乐

    2011-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

    Shyamapada Mandal; Manisha Deb Mandal; Nishith Kumar Pal

    2012-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

    陈丽峰; 柳君泽; 党永明; 宋熔

    2004-01-01

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

  2. Preparation of Silica Gel Immunoaffinity Column for Chloramphenicol Determination%硅胶载体氯霉素免疫亲和柱的制备

    Institute of Scientific and Technical Information of China (English)

    张灿; 周婷; 陆介宇; 段玉清; 王硕; 于娇

    2012-01-01

    以硅胶为载体,通过硅烷偶联剂3-氨基丙基三乙氧基硅烷在其表面引入氨基,采用戊二醛法与氯霉素抗体进行偶联。该方法制备的免疫亲和柱对氯霉素抗体的偶联率达到72%,对氯霉素的最大吸附容量达到80ng/mL柱体积,选择含70%甲醇的PBS为洗脱溶液。以牛奶为检测对象分别采用3种不同方法进行样品处理,利用免疫亲和柱实现对样品中痕量残留的氯霉素纯化富集并进行ELISA检测。%Silica gel was used as a carrier for preparing an immunoaffinity column (IAC) to determine chloramphenicol. Amino groups were introduced to the surface of silica gel using 3-aminopropyltriethoxysilane (APTES) as a silane coupling agent and the modified silica gel was conjugated with anti-chloramphenicol antibodies using glutaraldehyde. As a result, a conjugation ratio of 72% was obtained. The maximum adsorption capacity of the prepared IAC was 80 ng/mL. The elution solvent was PBS containing 70% methanol. After sample pretreatment by three different methods, chloramphenicol residues in milk were ourified and enriched using the IAC and determined by ELISA

  3. 酸性铬蓝K分光光度法测定氯霉素%Spectrophotometric Determination of Chloramphenicol with the Reagent Acid Chrome Blue K

    Institute of Scientific and Technical Information of China (English)

    江虹; 庞向东; 柯杉

    2012-01-01

    在pH9.66的Tris-盐酸缓冲溶液中,氯霉素与酸性铬蓝K反应形成具有正吸收和负吸收的离子缔合物,最大正吸收波长为498nm,最大负吸收波长为594nm,线性范围分别在3.2mg·L^-1(正吸收)、3.9mg·L^-1(负吸收)以内,表观摩尔吸光率分别为5.93×10^4L·mol^-1·cm^-1(正吸收)、2.32×10^5L·mol^-1·cm^-1(负吸收),据此建立了测定氯霉素含量的分光光度法。方法用于氯霉素注射液及滴眼液中氯霉素的测定,回收率在98.9%~101.2%之间,相对标准偏差(n=6)在0.8Yoo~1.2%之间。%In Tris HCl buffer solution of pH 9.66. an ionic association complex was formed by the reaction of chloramphenicol with acid chrome blue K, having its positive absorption maxmum at the wavelength of 498 nm and negative absorption maximum at 594 nm. Ranges of linearity and values of apparent molar absorptivity found at both absorption maxima were within 3.2 mg·L^-1 and 3.9 mg·L^-1, with their values of apparent molar absorptivity of 5. 935×10^4L·mol^-1·cm^-1 and 2. 32×10^5L·mol^-1·cm^-1 respectively. Based on these facts, a method of spectrophotometric determination of chloramphenicol was proposed, and applied to the determination of chloramphenicol in chloramphenicol injections and eye drops, giving values of recovery and RSI)'s (n= 6) in the ranges of 98. 9%-101.2% and 0.8%-1.2% respectively.

  4. Determination of Chloramphenicol Vaginal Tablets by HPLC%HPLC法测定氯霉素阴道片中氯霉素的含量

    Institute of Scientific and Technical Information of China (English)

    时正媛; 曾蔚欣; 孙路路

    2014-01-01

    Objective:To establish an HPLC method for the determination of chloramphenicol in chloramphenicol vaginal tablets. Methods:An Agilent ZORBAX SB-C18 column (150 mm × 4. 6 mm,5 μm)was used. The mobile phase was composed of 0. 1% sodi-um 1-heptanesulfonate solution-methanol (68∶32),the flow rate was 1. 0 ml·min-1, the UV detection wavelength was 277 nm,the column temperature was 35℃,and the injection volume was 10 μl. Results:The linear range of chloramphenicol was 25. 6-512. 0 μg ·ml-1(r=0. 999 9). The mean recovery was 99. 4%, and RSD was 0. 8%(n=9). Conclusion:The method is simple,accurate and reproducible,and can be used in the determination of chloramphenicol vaginal tablets.%目的::建立测定氯霉素阴道片中氯霉素含量的 HPLC法。方法:色谱柱为 Agilent ZORBAX SB-C18柱(150 mm ×4.6 mm,5μm),流动相为含0.1%庚烷磺酸钠的溶液-甲醇(68∶32),流速1 ml·min-1,检测波长277 nm,柱温35℃,进样量10μl。结果:氯霉素浓度在25.6~512.0μg·ml-1范围内与峰面积线性关系良好,r=0.9999,平均回收率为99.4%,RSD为0.8%(n=9)。结论:该法简便、准确、重复性好,适用于测定氯霉素阴道片中氯霉素的含量。

  5. Simultaneous determination of nitroimidazoles, benzimidazoles, and chloramphenicol components in bovine milk by ultra-high performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Wang, Yuanyuan; Li, Xiaowei; Zhang, Zhiwen; Ding, Shuangyang; Jiang, Haiyang; Li, Jiancheng; Shen, Jianzhong; Xia, Xi

    2016-02-01

    A sensitive, confirmatory ultra-high performance liquid chromatography-tandem mass spectrometric method was developed and validated to detect 23 veterinary drugs and metabolites (nitroimidazoles, benzimidazoles, and chloramphenicol components) in bovine milk. Compounds of interest were sequentially extracted from milk with acetonitrile and basified acetonitrile using sodium chloride to induce liquid-liquid partition. The extract was purified on a mixed mode solid-phase extraction cartridge. Using rapid polarity switching in electrospray ionization, a single injection was capable of detecting both positively and negatively charged analytes in a 9 min chromatography run time. Recoveries based on matrix-matched calibrations and isotope labeled internal standards for milk ranged from 51.7% to 101.8%. The detection limits and quantitation limits of the analytical method were found to be within the range of 2-20 ng/kg and 5-50 ng/kg, respectively. The recommended method is simple, specific, and reliable for the routine monitoring of nitroimidazoles, benzimidazoles, and chloramphenicol components in bovine milk samples.

  6. [Simultaneous determination of zeranols and chloramphenicol in foodstuffs of animal origin by combination immunoaffinity column clean-up and liquid chromatography-tandem mass spectrometry].

    Science.gov (United States)

    Wang, Qing; Wang, Guomin; Xi, Cunxian; Li, Xianliang; Chen, Dongdong; Tang, Bobin; Zhang, Lei; Zhao, Hua

    2014-06-01

    A combination immunoaffinity column (IAC-CZ) clean-up and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytical method was successfully developed for zearalenol, beta-zearalenol and zearalenone) and chloramphenicol (CAP) in foodstuffs of animal origin. The samples (fish, liver, milk and honey) were enzymatically digested by beta-glucuronidase/sulfatase for about 16 h and then extracted with ether. The extracts were evaporated to dryness and then the residues were dissolved by 1.0 mL of 50% acetonitrile solution. After filtered and diluted with PBS buffer, the reconstituted solution were cleaned-up with a IAC-CZ and then analyzed by LC-MS/MS in multiple reaction monitoring (MRM) mode. The chromatographic separation was performed on a Shimadzu Shim-pack VP-ODS column with gradient elution by acetonitrile and 2 mmol/L ammonium acetate solution. The detection was carried out by electrospray negative ionization mass spectrometry in MRM mode. The proposed method was validated by the limit of detection (0.04-0.10 microg/kg), linearity (R2 > or = 0.999 0), average recoveries (70.9%-95.6%) and precisions (2.0% - 11.8%). The developed method is reliable, sensitive and has good applicability. The combination immunoaffinity column was proved to be an effective pretreatment technique to decrease the matrix effect, and it met the requirements of residue analysis of co-occurring zeranols and chloramphenicol.

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

    Institute of Scientific and Technical Information of China (English)

    赵子瑞; 张迅; 张佳莉; 董敏; 李云兰

    2013-01-01

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

  8. Comparison of different calibration approaches for chloramphenicol quantification in chicken muscle by ultra-high pressure liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Pan, Xiao-Dong; Jiang, Wei; Wu, Ping-Gu

    2015-01-07

    Matrix-dependent signal suppression often occurs in quantitative analysis by ultra-high pressure liquid chromatography tandem mass spectrometry (UPLC-MS/MS). In this study, we investigated three calibration methods for compensation of signal suppression on chloramphenicol (CAP) quantification in chicken muscle. The data showed that the spiking recoveries by solvent standard calibration with a stable isotope labelled internal standard (SIL-IS) and matrix-matched standard calibration with a SIL-IS were significantly higher than by external matrix-matched standard calibration (P 0.05). The limit of detection (LOD) for external matrix matched standard calibration was 0.1 μg kg(-1), and that for SIL-IS calibration (including matrix matched and solvent dissolved standard) was 0.03 μg kg(-1).

  9. In-vitro permeability of the human nail and of a keratin membrane from bovine hooves: penetration of chloramphenicol from lipophilic vehicles and a nail lacquer.

    Science.gov (United States)

    Mertin, D; Lippold, B C

    1997-03-01

    Lipophilic vehicles and especially nail lacquers are more appropriate for topical application on the nail than aqueous systems because of their better adhesion. This work has, therefore, studied the penetration through the human nail plate of the model compound chloramphenicol from the lipophilic vehicles medium chain triglycerides and n-octanol and from a lacquer based on quaternary poly(methyl methacrylates) (Eudragit RL). The results were compared with data obtained with a keratin membrane from bovine hooves. If the swelling of the nail plate or the hoof membrane is not altered by use of lipophilic vehicles, the maximum flux of the drug is independent of its solubility in the vehicle and is the same as that from a saturated aqueous solution. These vehicles are not able to enter the hydrophilic keratin membrane because of their non-polar character and so cannot change the solubility of the penetrating substance in the barrier. If the concentration of the drug in the nail lacquer is sufficiently high, the maximum flux through both barriers equals that from aqueous vehicles or even exceeds it because of the formation of a supersaturated system. Penetration through the nail plate follows first order kinetics after a lag-time of 400 h. The course of penetration through the hoof membrane is initially membrane-controlled and later becomes a matrix-controlled process because of the membrane's greater permeability. Chloramphenicol is dissolved in the lacquer up to a concentration of 31%. The relative release rates from these solution matrices are independent of the drug concentration but they decrease on changing to a suspension matrix. These results show that drug flux is independent of the character of the vehicle and that penetration of the drug is initially membrane-controlled and changes to being matrix-controlled as the drug content of the lacquer decreases.

  10. A homogeneous and “off–on” fluorescence aptamer-based assay for chloramphenicol using vesicle quantum dot-gold colloid composite probes

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Yang-Bao [State Key Laboratory Base of Novel Functional Materials and Preparation Science, Faculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211 (China); Ren, Hong-Xia [Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041 (China); University of Chinese Academy of Sciences, Beijing 10049 (China); Gan, Ning, E-mail: ganning@nbu.edu.cn [State Key Laboratory Base of Novel Functional Materials and Preparation Science, Faculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211 (China); Zhou, You [State Key Laboratory Base of Novel Functional Materials and Preparation Science, Faculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211 (China); Cao, Yuting, E-mail: caoyuting@nbu.edu.cn [State Key Laboratory Base of Novel Functional Materials and Preparation Science, Faculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211 (China); Li, Tianhua [State Key Laboratory Base of Novel Functional Materials and Preparation Science, Faculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211 (China); Chen, Yinji [Faculty of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210000 (China)

    2016-07-27

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

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

    Directory of Open Access Journals (Sweden)

    Alshaibani MM

    2016-05-01

    resonance. Results: During screening procedure, SUK 25 exhibited good antimicrobial potential against several strains of MRSA. The best biological activity was shown from fraction number VII and its subfractions F2 and F3 with minimum inhibitory concentration values at 16 µg/mL and 8 µg/mL, respectively. These two subfractions were identified as diketopiperazine cyclo-(tryptophanyl-prolyl and chloramphenicol. Conclusion: On the basis of obtained results, SUK 25 isolated from Z. spectabile can be regarded as a new valuable source to produce secondary metabolites against bacteria, especially MRSA. Keywords: Zingiber spectabile, MRSA, SUK 25, cyclo-(tryptophanyl-prolyl, chloramphenicol, HR-MS, NMR

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

    Science.gov (United States)

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

    2016-01-04

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

  13. Novel spectrophotometric determination of chloramphenicol and dexamethasone in the presence of non labeled interfering substances using univariate methods and multivariate regression model updating

    Science.gov (United States)

    Hegazy, Maha A.; Lotfy, Hayam M.; Rezk, Mamdouh R.; Omran, Yasmin Rostom

    2015-04-01

    Smart and novel spectrophotometric and chemometric methods have been developed and validated for the simultaneous determination of a binary mixture of chloramphenicol (CPL) and dexamethasone sodium phosphate (DSP) in presence of interfering substances without prior separation. The first method depends upon derivative subtraction coupled with constant multiplication. The second one is ratio difference method at optimum wavelengths which were selected after applying derivative transformation method via multiplying by a decoding spectrum in order to cancel the contribution of non labeled interfering substances. The third method relies on partial least squares with regression model updating. They are so simple that they do not require any preliminary separation steps. Accuracy, precision and linearity ranges of these methods were determined. Moreover, specificity was assessed by analyzing synthetic mixtures of both drugs. The proposed methods were successfully applied for analysis of both drugs in their pharmaceutical formulation. The obtained results have been statistically compared to that of an official spectrophotometric method to give a conclusion that there is no significant difference between the proposed methods and the official ones with respect to accuracy and precision.

  14. Increased formation of halomethanes during chlorination of chloramphenicol in drinking water by UV irradiation, persulfate oxidation, and combined UV/persulfate pre-treatments.

    Science.gov (United States)

    Wenhai, Chu; Tengfei, Chu; Erdeng, Du; Deng, Yang; Yingqing, Guo; Naiyun, Gao

    2016-02-01

    Ultraviolet/persulfate (UV/PS) has been widely used to generate sulfate radicals for degradation of water organic pollutants in previous studies. However, its impacts on disinfection byproduct formation during post-chlorination of degraded compounds is unclear. The objective of this study was to evaluate the impacts of UV irradiation, PS oxidation, and the combined UV/PS advanced oxidation process (AOP) pre-treatments on halomethane formation during the following chlorination of chloramphenicol (CAP), a model antibiotic commonly found in wastewater-impacted water. Results showed that CAP could be transformed to more trichloromethane (TCM) than monochloromethane (MCM) and dichloromethane (DCM) in the presence of excess chlorine. UV photolysis, PS oxidation and UV/PS AOP all directly decomposed CAP to produce halomethanes (HMs) before post-chlorination. Moreover, UV and UV/PS pre-treatments both enhanced the formation of all the HMs in the subsequent chlorination. PS pre-oxidation decreased the TCM formation during post-chlorination, but increased the yields of MCM, DCM and total HMs. UV pre-irradiation significantly increased the bromide utilization of HMs, whereas UV/PS pre-oxidation decreased the bromine incorporation and utilization of HMs from the chlorination of CAP in a low-bromide water. UV irradiation, PS oxidation, and UV/PS AOP can inactivate pathogens and degrade organic pollutants, but this benefit should be weighed against a potential risk of the increased halomethane formation from degraded organic pollutants with and without post-chlorination.

  15. Real-time UV imaging of chloramphenicol intrinsic dissolution characteristics from ophthalmic in situ gel%实时紫外成像研究氯霉素眼用原位凝胶的固有溶出特征

    Institute of Scientific and Technical Information of China (English)

    陈建秀; 郭桢; 李海燕; 伍丽; 何仲贵; 胡容峰; 张继稳

    2013-01-01

    本文以氯霉素为模型药物,采集氯霉素从原位凝胶中溶出过程的紫外实时成像谱图,从而测得氯霉素原位凝胶的固有溶出速率,考察处方因素和pH、泪液等生理因素对氯霉素原位凝胶固有溶出特征的影响.结果表明,随着泊洛沙姆浓度的增大,氯霉素温敏原位凝胶的固有溶出速率明显减小;加入增稠剂会降低氯霉素的固有溶出速率,其中以卡波姆影响最大;不同泪液稀释比例对胶凝温度影响较大,对氯霉素的固有溶出速率影响较小;不同pH条件下氯霉素固有溶出速率无明显变化.氯霉素pH敏原位凝胶在弱酸性及中性条件下溶出速率比弱碱性条件下慢.氯霉素原位凝胶的固有溶出特征与处方因素、生理因素存在一定的相关性.实时紫外成像测定所需样品量少、检测迅速,可用于眼用原位凝胶的药物释放特征评价.%In this paper,chloramphenicol was selected as a model drug to prepare in situ gels.The intrinsic dissolution rate of chloramphenicol from in situ gel was evaluated using the surface dissolution imaging system.The results indicated that intrinsic dissolution rate of chloramphenicol thermosensitive in situ gel decreased significantly when the poloxamer concentration increased.The addition of the thickener reduced the intrinsic dissolution rate of chloramphenicol thermosensitive gel,wherein carbomer had the most impact.Different dilution ratios of simulated tear fluid greatly affected gel temperature,and had little influence on the intrinsic dissolution rate of chloramphenicol from the thermosensitive in situ gel.The pH of simulated tear fluid had little influence on the intrinsic dissolution rate of chloramphenicol thermosensitive in situ gel.For the pH sensitive in situ gel,the dissolution rates of chloramphenicol in weak acidic and neutral simulated tear fluids were slower than that in weak alkaline simulated tear fluid.In conclusion,the intrinsic dissolution of

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

    Science.gov (United States)

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

    2011-01-31

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1984-10-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Vijaya Bharathi Srinivasan

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

  20. Development of a Double Nuclear Gene-Targeting Method by Two-Step Transformation Based on a Newly Established Chloramphenicol-Selection System in the Red Alga Cyanidioschyzon merolae

    Science.gov (United States)

    Fujiwara, Takayuki; Ohnuma, Mio; Kuroiwa, Tsuneyoshi; Ohbayashi, Ryudo; Hirooka, Shunsuke; Miyagishima, Shin-Ya

    2017-01-01

    The unicellular red alga Cyanidioschyzon merolae possesses a simple cellular architecture that consists of one mitochondrion, one chloroplast, one peroxisome, one Golgi apparatus, and several lysosomes. The nuclear genome content is also simple, with very little genetic redundancy (16.5 Mbp, 4,775 genes). In addition, molecular genetic tools such as gene targeting and inducible gene expression systems have been recently developed. These cytological features and genetic tractability have facilitated various omics analyses. However, only a single transformation selection marker URA has been made available and thus the application of genetic modification has been limited. Here, we report the development of a nuclear targeting method by using chloramphenicol and the chloramphenicol acetyltransferase (CAT) gene. In addition, we found that at least 200-bp homologous arms are required and 500-bp arms are sufficient for a targeted single-copy insertion of the CAT selection marker into the nuclear genome. By means of a combination of the URA and CAT transformation systems, we succeeded in producing a C. merolae strain that expresses HA-cyclin 1 and FLAG-CDKA from the chromosomal CYC1 and CDKA loci, respectively. These methods of multiple nuclear targeting will facilitate genetic manipulation of C. merolae. PMID:28352279

  1. 氯霉素固体脂质纳米粒的制备及质量评价%Preparation and Quality Evaluation of Chloramphenicol Solid Lipid Nanoparticles

    Institute of Scientific and Technical Information of China (English)

    聂绩; 黄华

    2011-01-01

    目的:制备氯霉素固体脂质纳米粒(CAP-SLN)并考察其质量.方法:选取CAP与甘油棕榈酸硬脂酸酯(PrecirolATO 5)比例(药脂比)、泊洛沙姆含量、乳化温度和初乳-分散相的体积比为考察因素,包封率和载药量为评价指标,设计正交试验并优化处方.利用乳化蒸发-低温固化法制备CAP-SLN;同时以粒径、Zeta电位、包封率、栽药量、稳定性及体外释放度为指标评价其质量.结果:最佳制备处方药脂比为1:10,泊洛沙姆含量为2%,乳化温度为70℃,初乳-分散相的体积比为1:7.所制纳米粒平均粒径为227姗,Zeta电位为-30.5mV,平均包封率为65.9%,平均载药量为6.59%;于4℃环境中考察30d,其包封率、粒径无显著变化,25℃环境中包封率显著降低、粒径明显增大;在前4h内有明显突释现象,药物累积释放率达58.86%,48h时累积释放率达85.09%,体外释药行为符合Weibull方程.结论:该制荆处方设计和工艺方法可行,制剂质量符合要求,可达到缓释效果.%OBJECTIVE: To prepare Chloramphenicol solid lipid nanoparticles (CAP-SLN) and to study the quality of it.METHODS: The preparation technilogy of CAP-SLN was optimized by orthogonal test with the entrapment efficiency and drug loading amount as index and with proportion of CAP to Precirol ATO 5 (drug-to-lipid ratio), amount of poloxamer, emulsifying temperature, volume ratio of emulsion-disperse phase as factors. CAP-SLN was prepared by emulsification evaporation-low temperature solidification technique. The quality of preparation was evaluated with particle size, Zeta potential, drug-loading amount, stability and in vitro drug release rate as index. RESULTS: The optimal formulation was as follows: drug-to-lipid ratio of 1: 10, the weight of poloxamer of 2%, emulsifying temperature of 70 ℃, drug-to-lipid of 1: 7. The mean diameter of CAP-SLN was 227 nm.The zeta potential was -30.5 mV. The entrapment efficacy was 65.9%. The average drug

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

    Institute of Scientific and Technical Information of China (English)

    黎新明; 崔英德

    2008-01-01

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

  3. 市售动物源性食品中氯霉素类药物残留量的调查研究%Survey of chloramphenicol residues in animal-origin foods in the retailer

    Institute of Scientific and Technical Information of China (English)

    华娟; 方勤美; 熊春娥; 吴少明; 陈立松; 郑奎城; 傅武胜

    2013-01-01

    Objective To investigate the chloramphenicols residues of animal-original foods. Methods The edible portion of fish, shrimp and pork were ground with solidified carbon dioxide, homogenized and then stored in the frozen. The homogenized samples were extracted with ethyl acetate or acetonitrile, degreased with hexane, detected by liquid chromatography–tandem mass spectrometry (LC-MS/MS), and quantified by inter-nal standard method. Results The results obtained from the 229 samples showed that the positive rates of chloramphenicol florfenicol and thiamphenicol were 31.0%(71/229) (according to detection limit 0.03μg/kg), 9.60% (22/229) and 1.31% (3/229), respectively. The detection rates of chloramphenicol were obviously dif-ferent among the samples. The relative higher detection rate was found in pollen(100%, 3/3), followed by aq-uaculture fish (82.1%, 23/28), milk (75.0%, 24/32), pork (46.7%, 7/15), domestic honey (16.0%, 12/75) and imported honey (2/36, 5.6%) except none of chloamphenicols detected in shrimps. Thiamphenicol were de-tected in pork, milk, fish but florfenicol were only detected in honey and pork, and their residual levels were below the tolerance. Conclusion The problem of chloramphenicol illegally used in the aquaculture and ani-mal breeding still existed and the risk monitoring and legal action should be further strengthened.%  目的了解市售动物源性食品中氯霉素类药物的残留水平.方法取鱼、虾、猪肉可食部分,用干冰冷冻粉碎、均质后冷冻存放.预处理样品经溶剂提取,正己烷脱脂后,用液相色谱/质谱联用法(LC-MC/MS)检测,采用内标法定量.结果全部样品中氯霉素的检出率最高(按检出限0.03μg/kg判定),达31%(71/229),氟甲砜霉素和甲砜霉素的检出率分别为9.60%(22/229)和1.31%(3/229).不同类样品氯霉素的检出率差异较大,明虾中均未检出,花粉的检出率最高(100%,3/3),其他检出率由高到低分别为养殖鱼(82.1%,23/28)

  4. Determination of Chloramphenicol Residues in Milk by UPLC - MS/MS%超高效液相色谱法-串联质谱法测定牛奶中的氯霉素残留

    Institute of Scientific and Technical Information of China (English)

    武煊; 李小桥; 李玉平

    2012-01-01

    应用超高效液相色谱-串联质谱法建立了牛奶中的氯霉素的检测方法。样品经乙酸乙酯提取后,用正已烷除脂,经C18固相萃取小柱富集纯化后,以C18反相柱为分析柱,乙腈-0.5mmol/L乙酸铵溶液为流动相,采用电喷雾负电离源(ESI-),多反应监测模式(SRM),用内标法定量检测。该方法提高了检测灵敏性和分析结果的可靠性,能够适应大规模样品的分析要求。%A method for the detemlination of ehloramphenicol in milk was developed by Ultra Performance Liquid Chromatog- raphy - tanden mass spectrometry( UPLC - MS/MS). The sample were extracted by ethyl acetate and the fat was removed by hexane. The C18 solid phase extraction (SPE) column was use to enrich and purify the chloramphenicol in extraction solu- tion. The chromatographic separation was achieved on a C18 column with a mobile phrase consisting of aeetronitrile and 5mmol/L ethanamide solution. ESI - mode was adopted for the detection of chloramphenicol. And the compound was quan- tified under SRM mode by intemal standard method. The developed approach is characterized by short time consumption for chromatographic separation, so as to meet the requirements for rapid analysis of large - batch samples.

  5. A Quick Pretreatment Method for Determination of Chloramphenicol Residue in Royal Jelly by ELISA%ELISA检测蜂王浆氯霉素残留的快速前处理方法

    Institute of Scientific and Technical Information of China (English)

    李璟; 陈世界; 李凛; 童晋; 聂春梅; 陈洋

    2012-01-01

    We used the improved method (0. 1 mol/L Tris-TBE) to deal with royal jelly samples, then extracted chloramphenicol (CAP) with ethyl acetate. The whole processing only needs 25 min. Compare with the original method from the ELISA kit the OD450 values of the improved method were lower than those of the kit method. We added standard CAP solution to the samples treated by the improved method to verify the sensitivity of it. The OD450 value changed which were obviously different from samples without adding CAP(F<0. 05). It was indicated that there was no interfering agent in the process of pretreatment and coloration. The average RSD of enzyme-marked board is 1. 29% . wich is accord with the request of international determination of chloramphenicol residue. Our assay provides a quick pretreatment method to detect the CAP in royal jelly. It is useful in the high-throughput detection for the inspection and quarantine departments.%为获得一种能快速检测蜂王浆中氯霉素残留的前处理方法,采用改良的0.1 mol/L Tris-TBE(pH=8.0)溶液处理蜂王浆,结合乙酸乙酯提取氯霉素(CAP),处理时间约25 min.ELISA检测样品的OD450值明显低于试剂盒法,通过添加标准CAP溶液对改良法进行验证.结果表明,改良法提取的样品对不同CAP质量浓度表现出明显的 OD450值变化,与添加前比较差异显著(P<0.05),排除处理过程存在干扰显色的因素.改良法检测相同样品的平均相对标准偏差为1.29%,完全符合目前国际上氯霉素残留检测的要求.

  6. Otimização e validação intralaboratorial de método para análise de resíduos de cloranfenicol em leite caprino por cromatografia gasosa com detecção por captura de elétrons (CG/DCE Optimization and intralaboratorial validation of method for analysis of chloramphenicol residues in goat milk by GC/ECD

    Directory of Open Access Journals (Sweden)

    Jaff R. da Silva

    2010-01-01

    Full Text Available The presence of chloramphenicol residues in goat milk can cause toxic effects in the population. The present work consists of the optimization and validation of analytical methodology for determination of chloramphenicol residues in goat milk by GC/ECD. The extraction was made with ethyl acetate and the clean-up with SPE-C18. The identification was made by comparison of retention time and GC/MS, and the quantification by external standard. The method was selective, linearity (0.998, precise (5.8-13.4%, exact (69.87-73.71% and robust. The LOD and LOQ of method were 0.030 and 0.10 μg/kg, respectively. The method was efficiently for analysis of chloramphenicol in goat milk.

  7. 3种抗生素对热带爪蟾胚胎发育的毒性影响%On the effects of chloramphenicol erythromycin and tetracycline on the growing Xenopus tropicalis embryos

    Institute of Scientific and Technical Information of China (English)

    刘臻; 施华宏; 费宏; 尹大强

    2011-01-01

    由抗生素在畜牧养殖业中的滥用造成的水环境污染问题及其对水生生物的毒害作用日益受到关注.用0.5~ 1.5 g/L的氯霉素(Chloramphenicol)、红霉素(Erythromycin)和0.01 ~ 0.5 g/L的四环素(Tetracycline)对热带爪蟾(Xenopus tropicalis)胚胎进行72 h暴露.结果表明,1.25 g/L和1.5 g/L的氯霉素使胚胎存活率分别下降了7%和14%,红霉素对胚胎存活无明显影响,0.5 g/L四环素导致胚胎全部死亡.1.5 g/L的氯霉素和红霉素使胚胎体长分别减少了7%和9%,0.25 g/L的四环素使胚胎体长减少了4%.3种抗生素能引起围心腔水肿、泄殖腔增大或拉长、肛门扩张和尾部弯曲等多种畸形现象,1.5g/L的氯霉素造成的总畸形率和围心腔水肿率分别为44%和34%;1.5 g/L的红霉素造成的总畸形率和泄殖腔增大率分别为22%和20%;0.25 g/L四环素造成的总畸形率和肛门扩张率分别为75%和59%.3种抗生素对热带爪蟾胚胎的发育毒性从大到小为四环素、氯霉素、红霉素.%In this paper, we have turned our efforts to the study of the effects of chloramphenicol erythromycin and tetracycline on the growing Xenopus tropicalis embryos. As is well known, due to the abuse of antibiotics in the aquaculture industry and the livestock husbandry, it has been found that antibiotics has made more and more serious impact on the aquatic environment, including the growth of Xenopus tropicalis embryos. Therefore, global declining amphibian populations have drawn special attention since the early 1990s, but the trend of increased use of pesticides and other toxic chemicals cannot be stopped but keep going on, which becomes one of the underlying reasons responsible for the worsening trend. This paper reveals the results of our experimental fact on how the embryos of Xenopus tropicalis, a kind of West African clawed frog has been seriously affected from the stage NF 11 - 12 to 0.5 - 1.5 g/L chloramphenicol (CAP

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

    Institute of Scientific and Technical Information of China (English)

    熊明洲; 李雁; 李璐; 解新安; 郑璐丝

    2012-01-01

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

  9. Degradation of chloramphenicol in aqueous solution using ozone oxidation in a two-phase system of water/loaded ozone organic solvent%水/载O3有机溶剂两相臭氧氧化法降解水体中氯霉素

    Institute of Scientific and Technical Information of China (English)

    李时银; 史震宇; 陆继来; 邹敏; 张利民

    2011-01-01

    Using a two-phase system of water/perfluorodecalin organic solvent loaded ozone, degradation of chloramphenicol in aqueous solution was conducted. Due to perfluorodecalin has a high ozone stability and solubility, chloramphenicol was used to examine the efficiency of the two-phase ozonation system. During the experiments, effects of initial pH and free radical scavenger on the removal rate of chloramphenicol were investigated respectively. The results showed that the efficiency of two-phase ozonation was increased with the increase of initial pH in water. It was also observed that free radical scavenger had no significant negative effect in two-phase ozonation.%以水/载O3有机溶剂(全氟萘烷)为新型两相臭氧氧化体系,研究了臭氧在全氟萘烷中的溶解度和稳定性,并考察了pH、NaHCO3和叔丁醇对两相体系中臭氧稳定性的影响;以水体中氯霉素为研究对象,考察了初始pH值和自由基抑制剂对两相臭氧氧化体系降解氯霉素效果的影响.结果表明:初始水相pH增大有利于氯霉素的降解;自由基抑制剂对两相体系氧化降解氯霉素影响不显著.

  10. Effect of Solution pH Value on Chloramphenicol Extraction Detected by Gas Chromatography-Mass Spectrometry%酸碱度对气相色谱-质谱联用法检测氯霉素提取的影响

    Institute of Scientific and Technical Information of China (English)

    王峰恩; 陈子雷; 王文博; 丁蕊艳; 杜红霞; 霍鲁格

    2011-01-01

    为使检测结果更准确,研究了溶液酸碱度对氯霉素提取的影响.在9种不同pH值的水溶液中添加氯霉素标准品,乙酸乙酯提取后,用N,0-双(三甲基硅基)三氟乙酰胺(BSTFA)-三甲基氯硅烷(rMCS)进行硅烷化处理,用正己烷溶解后,使用气相色谱-质谱联用法(GC/MS)检测氯霉素衍生物.通过全扫描质谱图和NIST标准质谱图的对比,对氯霉素衍生物进行定性确定;通过测定特征离子m/z 225的值对其定量;再将提取后的水溶液残液全部调至pH=5.5左右,重新检测以确认氯霉素在一些样品中未检出的原因.结果表明,强酸强碱中的氯霉素发生不可逆的分解,在提取氯霉素时应保持中性偏酸环境以达到最佳提取效果.%To make sure the results more accurate, the effects of different solution pH values on the chloramphenicol extraction were studied. The standard chloramphenicol was added into 9 kinds of solutions' with different pH values, and then extracted with ethyl acetate after 24 hours. After silylation processing with N, O - di (trimethyl silicon - based) three fluorine acetamide (BSTFA) - trimethyl chlorine silicon hydride (TMCS) and dissolved by normal hexane, the chloramphenicol derivatives were detected by gas chromatogra-phy -mass spectrum (GC/MS). The qualitative detection was conducted through the comparison between the entire chromatograph chart and the NIST standard mass spectrum chart, while the quantitative determination was conducted through detecting the value of characteristic ion m/z 225. At last, the pH value of the residual sample after extraction was adjusted to about 5.5 and detected again to confirm the reason why some chloram phenicol was undetectable. The results showed that the chloramphenicol could be decomposed irreversibly in strong acid or alkali, and the neutral meta - acid solution was better for extraction.

  11. 集胞藻胞外聚合物(EPS)与氯霉素的相互作用%Interaction between Chloramphenicol and the Extracellular Polymeric Substances from Cyanobacterium Synechocystis sp.

    Institute of Scientific and Technical Information of China (English)

    付庆龙; 张道勇; 牟书勇; 潘响亮

    2012-01-01

    Three-dimensional excitation emission matrix (EEM ) fluorescence spectroscopy was used to examine the interaction between chloramphenicol ( CAP) and the extracellular polymeric substances (EPS) from Synechocystis sp. The results showed that there were six particular fluorescence peaks in the spectra of EPS. Peak A (EX/EM =205/304) , peak B (EX/EM =230/302) , peak C (EJEm = 235/354) and peak D (EX/EM =260/372) represented the protein-like fluorescence substances, and the other two peaks at ExIEm = 275/446 (peak E) and EX/EM =350/452 (peak F) reflected the humic-like fluorophores. With the exception of peak F, all the fluorescence peaks could be significantly quenched by CAP. This indicated that the fluorophores material can play a role with CAP, but not between CAP and those reflected by peak F. The reaction between CAP and the fluorophores in EPS was a static process, and formed stable EPS-CAP complexes. The effective quenching and binding constants for fluorophores of EPS were 3. 28-4. 49 and 4. 54-8. 13, respectively. The strong combination of EPS to CAP implied that EPS may play an important role in the transfer and transformation of CAP in aquatic environments.%通过利用激发-发射矩阵(EEM)荧光光谱,研究蓝藻集胞藻EPS(胞外聚合物)与CAP(氯霉素)的相互作用.结果表明:EPS含有6个峰,其中峰A(Ex/Em=205/304)、峰B(Ex/Em=230/302)、峰C(Ex/Em=235/354)和峰D(Ex/Em=260/372)为类蛋白峰,峰E(Ex/Em=275/446)和峰F(Ex/Em=350/452)为类腐殖质峰.除峰F外,其他各峰都能被CAP猝灭,说明它们所代表的物质能够与CAP发生作用;而峰F则几乎不被CAP猝灭,即荧光峰F不与CAP发生作用.CAP与EPS中荧光基团的反应属于静态猝灭,生成稳定的不发荧光的EPS-CAP络合物,其有效猝灭常数为3.28~4.49,结合常数为4.54~8.13.EPS与CAP强的络合作用意味着环境中普遍存在的EPS可能深刻地影响CAP在水环境中的迁移与转化.

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

    Directory of Open Access Journals (Sweden)

    Helio Alves Martins Júnior

    2006-06-01

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

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

    Institute of Scientific and Technical Information of China (English)

    张小毅; 刘巨源; 邱乐乐; 贾岩龙

    2012-01-01

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

  14. Determination of residues of chloramphenicol, thiamphenicol and florfenicol in shrimp by isotope dilution liquid and chromatography tandem mass spectrometry%同位素内标稀释液相色谱-串联质谱法测定虾中氯霉素、甲砜霉素和氟甲砜霉素残留量

    Institute of Scientific and Technical Information of China (English)

    陈剑刚; 张艳; 白艳玲; 冯翠霞; 梁素丹

    2013-01-01

    目的:建立了虾中氯霉素、甲砜霉素、氟甲砜霉素三种氯霉素类药物残留的同位素稀释高效液相色谱-串联质谱测定方法.方法:以氘代氯霉素(CAP-d5)为内标,样品用乙腈提取,正己烷脱脂,LC-Si硅胶柱净化,丙酮-正己烷洗(6+4)洗脱后吹氮浓缩.采用Atlantis(R)T3质谱柱分离,以乙腈-水-乙酸铵溶液为流动相进行梯度洗脱,以负离子多反应监测模式、同位素内标法定量.结果:方法的检出限和定量限分别为0.03 μg/kg、0.10 μg/kg;氯霉素、甲砜霉素、氟甲砜霉素回收率分别为82.0% ~ 99.3%、73.5% ~85.6%、76.0% ~ 98.5%;相对标准偏差为4.0%-12.5%.应用建立的方法对90份虾样进行分析,其中3份检出氯霉素,含量为1.0 μg/kg ~ 4.3 μg/kg.结论:本法具有非常高的选择性、灵敏度和准确度,完全能满足虾中痕量氯霉素类药物残留的高灵敏分析.%Objective:The method for the determination of three chloramphicols including chloramphenicol (CAP),thiamphenicol(TAP) and florfenicol(FF) in shrimp was developed by isotope dilution liquid and chromatography tandem Mass Spectrometry (LC-MS/MS).Methods:With chloramphenicol-d5 (CAP-d5) as internal standard,samples were extracted with acetonitrile,defatted with hexane,cleaned through LC-Si solid-phase column,eluted with acetone-hexane (6 + 4),evaporated by nitrogen gas to nearly dry.The extract components were separated completely on a Atlantis (R) T3 column with acetonitrile-water-10mmol.Lammonium acetate for gradient elution and simultaneously quantified by the isotope internal standard under the negative ion mode using multiple reactions monitoring mode.Results:The limits of detection for CAP,TAP and FF were the same as 0.03 μg/kg,and the limit of quantification were 0.10 μg/kg.The average recoveries of CAP,TAP and FF for spiked blank sample were 82.0% ~ 99.3%,73.5% ~ 85.6%,76.0% ~ 98.5% respectiVely,and their relative

  15. Ag@ AgCl等离子体负载TiO2光催化剂的制备及其对氯霉素的降解研究%Preparation of Ag@ AgCI Supported TiO2 Plasma Photocatalysts and Photocatalytic Degradation of Chloramphenicol

    Institute of Scientific and Technical Information of China (English)

    钮金芬; 姚秉华; 魏佳; 余晓皎

    2011-01-01

    The anatase TiO2 was prepared by steam heating method. AgCl nanoparticles were then loaded onto the TiO2 via deposition-precipitation, and some of the Ag+ particles were reduced to Ag particles by photo reduction method. Ag@ AgCl supported TiO2 plasma photocatalysts can be obtained. The products are characterized by XRD,TEM and DRS spectroscopy. The photocatalytic activity is evaluated using chloram-phenicol (CAP) degradation under UV and visible light irradiation. The results indicate that the Ag@ AgCl supported TiO2 plasma photocatalysts significantly improve the photocatalytic degradation of CAP performance. The degradation rate is about 95% after high-pressure mercury lamp irradiation of CAP solution of 50 mg/L for 30 min ,and 60% after Xe lamp irradiation of CAP solution of 50 mg/L for 180 min.%采用蒸汽热法制备锐钛矿相TiO2,利用沉积-沉淀法和光化学反应将AgCl分散到TiO2上,通过光化学反应将Ag+还原,获得Ag@ AgCl等离子体负载TiO2光催化剂.通过XRD、TEM、UV-vis漫反射吸收光谱(DRS)对产物进行表征,研究光催化剂对氯霉素的光催化降解性能.结果表明,Ag@ AgCl等离子体负载TiO2光催化剂对氯霉素具有良好的光催化活性,其在高压汞灯下30 min的降解率可达95%,在Xe灯下180 min的降解率可达60%.

  16. 液相色谱-质谱法检测渔业养殖水中硝基呋喃及氯霉素药物%Determination of 4 Nitrofurans and Chloramphenicol in Fisheries Water by Liquid Chromatography Coupled Tandem Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    张立坚; 张俊杰; 张良滔; 蔡春

    2011-01-01

    建立了同时测定渔业养殖水中呋喃唑酮、呋喃西林、呋喃妥因和呋喃它酮及氯霉素等5种抗生素药物的超高压液相色谱-电喷雾电离串联质谱(UPLC-ESI-MS/MS)分析方法.水样用HLB萃取柱净化、浓缩后,洗脱液经氮气吹于,残渣用V(乙腈)∶V(水)=1∶1混合溶液溶解,以乙腈和0.1%甲酸水溶液为流动相,经ZORBAX SB-C18色谱柱分离后,用串级质谱多反应监测模式做定性定量分析.该方法在0.5 μg/L或1~40 μg/L浓度范围内具有良好的线性,相关系数均大于0.996,检出限(S/N=3)为0.5~1μg/L,平均回收率为90.3%~104.2%,相对标准偏差为5.4%~10.0%.%An ultra high-pressure liquid chromatography coupled electrospray ionization triple-quadruple tandem mass spectrometry (UPLC-ESI MS/MS) was used for the simultaneous determination of furazolidone, nitrofarazone, nitrofarantoin, furaltadone and chloram-phenicol in fisheries water. The drugs were extracted and cleaned up by Oasis HLB solid phase extraction cartridge. The extract was evaporated to dryness under nitrogen and reconstituted in solution with V(acetonitrile): V(water) = l: 1. The 5 drugs were separated and detected by ZORBAX SB-C18 using 0.1% formic acid (A) and acetonitrile (B) as mobile phase. The target compounds were confirmed and quantified by MS/MS under multiple reactions monitoring (MRM) mode with external standard method. Under the optimal condition, the calibration curves of 5 drugs show good linearity with the correlation coefficients rather than 0. 997 in the range of 0. 5 μg/L or 1-40 μg/L, the limits of detection(LODs)range from 0.5-1. 0 μg/L (S/N = 3) , the average recoveries of 5 drugs are in the range of 90. 3%-104. 2% , and the relative standard deviations(RSDs) are 5. 4%-10.0%.

  17. 基于磁性金属有机框架化合物-适配体探针的氯霉素仿生比色传感器研究%A Colorimetric Bionic Aptasensor Base on Magnetic Metal Organic Framework Compound-Aptamer Probe for Specific Detection of Chloramphenicol

    Institute of Scientific and Technical Information of China (English)

    吴彩叶; 缪养宝; 朱云云; 干宁; 欧昌荣; 曹锦轩

    2016-01-01

    构建了一种基于磁性金属有机框架化合物( MOF)-适配体探针的仿生比色传感器,用于食品中氯霉素残留分析。首先将氯霉素( CAP)的适配体标记到Fe3 O4磁珠上获得捕获探针,进而采用该适配体的互补链标记到铁基MOF( Fe-MOF)上作为纳米示踪剂( MOF-cDNA),将捕获探针和示踪剂杂交结合后,可获得铁磁性仿生复合探针。当氯霉素和此类探针孵育后,其与捕获探针上的适配体结合,将纳米示踪剂释放到溶液中,并经过磁分离后进入上清液。由于Fe-MOF具有过氧化物酶的性质,可以催化TMB-H2 O2系统显色,由此构建了一种高选择性的氯霉素比色传感器。在最佳反应条件下,本法对氯霉素的检测范围在0.001~10 ng/mL之间,最低检出限为0.3 pg/mL(S/N=3),实际样品的加标回收率为86.9%~93.5%,且不受其它抗生素干扰。用此方法检测牛奶样品中氯霉素的结果与商业化ELISA方法一致。此类无酶标记仿生探针具有高催化活性且成本较酶标探针大大降低;该分析方法利用磁分离简化了前处理步骤,可用于奶制品中氯霉素的快速灵敏分析。%A colorimetric bionic aptasensor based on magnetic metal organic framework ( MOF ) compound-aptamer bionic probe was designed for detecting chloramphenicol ( CAP ) . In this assay, the aptamer was labeled on the magnetic beads as capture probe and its complementary strand ( cDNA ) was immobilized on MOF as the nanotracer composite probe, and the ferromagnetic biomimetic composite probe was obtained by hybridizing the capture probe with the tracer. When the composite probe solution was incubated with CAP, the aptamer on the capture probes preferentially combines with CAP, and the signal tag was substituted into supernatant after magnetic separation. The supernatant containing numerous MOF could efficiently catalyze tetramethylbenzidine ( TMB )-H2 O2 solution for the color development

  18. 77 FR 41412 - Determination That CHLOROMYCETIN (Chloramphenicol) Capsules, 250 Milligrams, Were Withdrawn From...

    Science.gov (United States)

    2012-07-13

    ... Research, Food and Drug Administration, 10903 New Hampshire Ave., Bldg. 51, Rm. 6312, Silver Spring, MD.... CHLOROMYCETIN is an antibiotic indicated to treat only serious infections for which less potentially dangerous.... In the Federal Register of February 11, 2009 (74 FR 6896), FDA announced that it was...

  19. Gold Magnetic Nanoparticles-based Chemiluminescent Immunoassay for Detection of Chloramphenicol in Milk

    Directory of Open Access Journals (Sweden)

    Wang Linyu

    2017-01-01

    Full Text Available chemiluminescent immunoassays (CLIA based on gold magnetic nanoparticles (Au-MNPs were developed for rapid analysis of chloramphen icol (CAP in milk sample. Anti-CAP antibodies were immobilized on the surfaces of Au-MNPs, luminol (Method I and 2′,6′-DiMethylcarbonylphenyl-10-sulfopropylacridinium-9-carboxylate 4′-NHS Ester, (NSP-DMAE-NHS, Method II were exploited in competitive CLIA for CAP detection in milk using a homemade luminescent measurement system. The sensitivities and limits of detection (LODs of the two methods were obtained according to the inhibition curves. It indicated that NSP-DMAE-NHS as luminescence reagent (reaction II was more sensitive and effective than luminol (reaction I. The LOD of reaction II reached 0.008 ng/ml while it was 4 ng/ml in reaction I. Moreover, the linear range of the inhibition curve of the former was wider than that of the latter. Such results indicated that the proposed CLIA stratery employing NSP-DMAE-NHS was more sensitive than other immunoassay method for CAP detection.

  20. 77 FR 4895 - New Animal Drugs; Chloramphenicol, Diethylcarbamazine Citrate, Hygromycin B, Methoxyflurane...

    Science.gov (United States)

    2012-02-01

    ..., Penicillin G, Phenylbutazone, Pyrantel Tartrate, Tylosin Phosphate, and Sulfamethazine AGENCY: Food and Drug..., NJ 08310. NADA 049-890 NORCO T-2 Pre-Pak Norco Mills of (tylosin phosphate). Norfolk, Inc., P.O. Box... procaine). 93257. NADA 095-953 MOORMABOOST TY 4000 ADM Alliance Medicated (tylosin Nutrition,...

  1. The effect of chloramphenicol on synthesis of ΦX 174-specific proteins and detection of the cistron A protein

    NARCIS (Netherlands)

    Mei, D. Van Der; Zandberg, J.; Jansz, H.S.

    1972-01-01

    Synthesis of ΦX 174-specific proteins in Escherichia coli H 502 was examined on sodium dodecyl sulphate-acrylamide gels by coelectrophoresis of proteins from [3H]leucine-labelled infected cells and [14C]leucine-labelled reference cells, which had been infected with ultraviolet-light irradiated phage

  2. Beneficial effect of Berberis buxifolia Lam, Ziziphus mistol Griseb and Prosopis alba extracts on oxidative stress induced by chloramphenicol.

    Science.gov (United States)

    Albrecht, Claudia; Pellarin, Gabriela; Rojas, María José; Albesa, Inés; Eraso, Alberto F

    2010-01-01

    The chemiluminescence of luminol, a measure of oxidative stress, increased immediately as a consequence of reactive oxygen species (ROS) stimulated by this antibiotic. The effect of Ch was dose dependent with maximum stimulus at 8 mg/ml (Vmax); above this concentration the cells began to reduce the production of ROS. The oxidative injury of Ch was counteracted by water extracts of Berberis buxifolia lam, Zizyphus mistol Griseb and Prosopis alba, indigenous fruits from Argentina. The relatively light units (RLU) emitted decreased immediately as a consequence of a protective effect exerted by the extracts of these fruit extracts on blood cells. The three indigenous fruit extracts reduced to a different extent the oxidative injury caused by Ch. B.buxifolia lam exhibited the highest antioxidant capacity followed by Z.mistol Griseb. Water extracts of both fruit extracts were the most effective against the oxidative stress, while P.alba presented better antioxidant capacity in the ethanolic fraction obtained. Hexane extracts showed low protective action on blood cells, with little reduction of area under curve (AUC) of RLU plotted versus time. Leukocytes remained viable in blood samples incubated for 3h with Ch and water extracts of B. buxifolia lam or Z. mistol Griseb (97.1% and 92.5% viability by Trypan blue exclusion, respectively); whereas with Ch only the cells were stressed and viability decreased to 30%. The three fruit extracts protected the viability of leukocytes in parallel with the decrease of ROS. Erythrocytes were not lysed in the presence of Ch.

  3. Comparison between Source-induced Dissociation and Collision-induced Dissociation of Ampicillin, Chloramphenicol, Ciprofloxacin, and Oxytetracycline via Mass Spectrometry

    OpenAIRE

    2013-01-01

    Mass spectrometry (MS) is a very powerful instrument that can be used to analyze a wide range of materials such as proteins, peptides, DNA, drugs, and polymers. The process typically involves either chemical or electron (impact) ionization of the analyte. The resulting charged species or fragment is subsequently identified by the detector. Usually, single mass uses source-induced dissociation (SID), whereas mass/mass uses collision-induced dissociation (CID) to analyze the chemical fragmentat...

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

    Directory of Open Access Journals (Sweden)

    Kargar, M. (PhD

    2014-11-01

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

  5. Drug: D07675 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available WITH CORTICOSTEROIDS G01AA Antibiotics G01AA05 Chloramphenicol D07675 Chloramphenicol succinate J ANTIINFEC... S01A ANTIINFECTIVES S01AA Antibiotics S01AA01 Chloramphenicol D07675 Chloramphenicol succinate S02 OTOLOGIC

  6. Delayed release of chloramphenicol from poly(2-hydroxyethylmethacrylate-co-acrylamide)hydrogels%Poly(HEMA-co-AAm)水凝胶对氯霉素的缓释作用

    Institute of Scientific and Technical Information of China (English)

    崔英德; 黎新明

    2008-01-01

    @@ Introduction The success of the therapy with ophthalmic drugs strongly depends on achieving enough drug concentration on the cornea for a sufficient period of time,but the typical delivery of drugs by eye-drops which currently account for more than 90% of all ophthalmic formulations is very inefficient and in some instances leads to serious side effects[1-3].Soft contact lenses have been proposed as a new vehicle for ophthalmic drug delivery[4].

  7. Antibacterial application of engineered bacteriophage nanomedicines: antibody-targeted, chloramphenicol prodrug loaded bacteriophages for inhibiting the growth of Staphylococcus aureus bacteria.

    Science.gov (United States)

    Vaks, Lilach; Benhar, Itai

    2011-01-01

    The increasing development of bacterial resistance to traditional antibiotics has reached alarming levels, thus there is an urgent need to develop new antimicrobial agents. To be effective, these new antimicrobials should possess novel modes of action and/or different cellular targets compared with existing antibiotics. Bacteriophages (phages) have been used for over a century as tools for the treatment of bacterial infections, for nearly half a century as tools in genetic research, for about two decades as tools for the discovery of specific target-binding proteins and peptides, and for almost a decade as tools for vaccine development. We describe a new application in the area of antibacterial nanomedicines where filamentous phages can be formulated as targeted drug-delivery vehicles of nanometric dimensions (phage nanomedicines) and used for therapeutic purposes. This protocol involves both genetic and chemical engineering of these phages. The genetic engineering of the phage coat, which results in the display of a target-specificity-conferring peptide or protein on the phage coat, can be used to design the drug-release mechanism and is not described herein. However, the methods used to chemically conjugate cytotoxic drugs at high density on the phage coat are described. Further, assays to measure the drug load on the surface of the phage and the potency of the system in the inhibition of growth of target cells as well as assessment of the therapeutic potential of the phages in a mouse disease model are discussed.

  8. Determination of Content in Chloramphenicol Injection by Turbidimetry%比浊法测定氯霉素注射液含量

    Institute of Scientific and Technical Information of China (English)

    李正群; 姜红; 张春瑛; 沈佳特

    2002-01-01

    目的:验证比浊法测定氯霉素效价方法可行性.方法:建立比浊法测定氯霉素含量,并将比浊法测定的结果与扩散法、高效液相法、紫外分光法结果相比较.结果:比浊法、扩散法、高效液相法结果一致.结论:比浊法测定氯霉素效价快速、可行.

  9. Determination of chloramphenicol in bovine urine, meat and shrimp by GC-MS. Method validation according to Commission Decision 2002/657/EC

    NARCIS (Netherlands)

    Rossum HJ van; Kootstra PR; Sterk SS; ARO

    2004-01-01

    Dit rapport beschrijft de validatie, de kwantificering en de wijze van identificatie van een analysemethode voor de bepaling van lage concentraties (0,1-1,0 micro g/kg) chlooramphenicol in monsters urine, garnalen en spierweefsel (vlees) Deze validatie is gebaseerd op de criteria beschreven in d

  10. TMFunction data: 906 [TMFunction[Archive

    Lifescience Database Archive (English)

    Full Text Available nesis 5 Chloramphenicol resistance (ug/ml) Chloramphenicol resistance (ug/ml) ... Q1RE83_ECOUT Helix ... transporter; multidrug recognition; cysteine; proton electrochemical gradient

  11. TMFunction data: 908 [TMFunction[Archive

    Lifescience Database Archive (English)

    Full Text Available nesis 5 Chloramphenicol resistance (ug/ml) Chloramphenicol resistance (ug/ml) ... Q1RE83_ECOUT Helix ... transporter; multidrug recognition; cysteine; proton electrochemical gradient

  12. TMFunction data: 907 [TMFunction[Archive

    Lifescience Database Archive (English)

    Full Text Available nesis 5 Chloramphenicol resistance (ug/ml) Chloramphenicol resistance (ug/ml) ... Q1RE83_ECOUT Helix ... transporter; multidrug recognition; cysteine; proton electrochemical gradient

  13. Drug: D07674 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available EPTICS, EXCL. COMBINATIONS WITH CORTICOSTEROIDS G01AA Antibiotics G01AA05 Chloramphenicol D07674 Chloramphen...1A ANTIINFECTIVES S01AA Antibiotics S01AA01 Chloramphenicol D07674 Chloramphenico...mphenicols J01BA01 Chloramphenicol D07674 Chloramphenicol stearate S SENSORY ORGANS S01 OPHTHALMOLOGICALS S0

  14. Experimental research on anti-inflammatory and analgesic effects of betamethasone and chloramphenicol cream%倍他米松氯霉素霜抗炎镇痛作用的实验研究

    Institute of Scientific and Technical Information of China (English)

    杨军炎; 吴彦; 盛国荣

    2008-01-01

    目的: 考察倍他米松氯霉素霜镇痛、抗炎消肿的功效.方法: 采用热板法与电刺激法两种致痛动物模型和二甲苯对小鼠腹部皮肤毛细血管通透性的影响与角叉菜胶对大鼠足跖肿胀的影响两种炎症动物模型,对倍他米松氯霉素霜的保护作用和治疗效果作了研究,并与肤乐乳膏进行了对比试验.结果: 倍他米松氯霉素霜能提高热板法致痛模型的痛阈,减少电刺激致痛的发生率,抑制毛细血管的通透性,减少炎性肿胀,显示了良好的镇痛与抗炎作用,并呈现明显的量效关系;在相同剂量下,镇痛作用显著优于肤乐乳膏(P<0.01),抗炎作用优于肤乐乳膏(P<0.05).结论: 倍他米松氯霉素霜能改善皮肤疾病的疼痛和水肿渗出症状,为临床应用提供了实验依据.

  15. Determination of Chloramphenicol in Eye Drops by New Vierordt Method%联立方程新解法测定氯霉素滴眼液中氯霉素含量

    Institute of Scientific and Technical Information of China (English)

    李祥; 俞炳林

    2003-01-01

    目的建立联立方程新解法测定滴眼液中氯霉素含量.方法用联立方程新解法直接测定氯霉素含量.278nm为测定波长,259nm为参比波长,水作空白,并与药典法进行比较.结果方法平均回收率为99.10%±0.11%,RSD为0.12%.测定结果与药典法相比没有显著差别.结论本方法可排除干扰直接测定滴眼液中氯霉素含量.

  16. Rapid Analysis of Chloramphenicol Residue in Milk by Near Infrared Spectrometry%近红外光谱法快速检测牛奶中氯霉素残留

    Institute of Scientific and Technical Information of China (English)

    王彩云; 相秉仁; 张伟; 王正武; 陈昌云

    2009-01-01

    本研究利用近红外透射技术和偏最小二乘法(PLS)快速测定牛奶中氯霉素残留含量,氯霉素残留的预测值与真实值的相关系数达0.9893,预示集的甲均回收率为99.77%.结果表明该方法可快速测定牛奶中氯霉素残留含量.

  17. Comparison of rose bengal-chloramphenicol and modified aureomycin-rose bengal-glucose-peptone agar as media for the enumeration of molds and yeasts in water by membrane filtration techniques.

    Science.gov (United States)

    Albaum, Silva; Masaphy, Segula

    2009-03-01

    The present study compares the suitability of rose bengalchloramphenicol (RBCh) and modified aureomycin-rose bengal glucose-peptone agar for enumerating fungi recovered from diverse water sources using the membrane filtration method. Both mold and yeast colonies were established more rapidly, with more intensified colony colors and higher RBCh counts.

  18. HPLC法同时测定双氯达克乳膏中氯霉素和丙酸氯倍他索的含量%Determination of Chloramphenicol and Clobetasol Propionate in Shuanglvdake Cream by HPLC

    Institute of Scientific and Technical Information of China (English)

    袁杰; 张琳; 黄雄伟; 张纯

    2010-01-01

    目的:建立以高效液相色谱法同时测定双氯达克乳膏中氯霉素和丙酸氯倍他索含量的方法.方法:色谱柱为YMCPack ODS-A,流动相为0.02 mol·L~(-1)磷酸二氢钾-甲醇(30:70),检测波长为240 nm,进样量为20 μL,流速为1 mL·min~(-1),柱温为25℃.结果:氯霉素、丙酸氯倍他索检测浓度的线性范围分别为7~35、0.4~2μg·mL~(-1)(r=0.9999),平均回收率分别为99.80%、99.92%,日内、日问RSD分别为1.20%、1.31%,1.59%、1.47%.结论:本方法操作简便、快速,结果准确可靠,适用于该制剂的含量测定.

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

    Digital Repository Service at National Institute of Oceanography (India)

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

    carried out with natural marine biofilms from a tropical monsoon-influenced environment to evaluate the interactions between bacteria and diatoms through application of antibiotics (streptomycin and chloramphenicol). Overall, chloramphenicol inhibited...

  20. Drug: D04106 [KEGG MEDICUS

    Lifescience Database Archive (English)

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

  1. Determination of Chloramphenicol Residues in Shrimp by Gas Chromatography-Triple Quadrupole Mass Spectrometry Using Stable Isotope Dilution Technique%同位素稀释气相色谱-三重四极杆质谱测定虾仁中氯霉素

    Institute of Scientific and Technical Information of China (English)

    曹艳平; 辛成龙; 季萍

    2015-01-01

    建立了一种稳定同位素稀释技术测定虾仁中氯霉素的气相色谱-三重四极杆质谱分析方法.样品中氯霉素用乙酸乙酯提取,以N,O-双三甲基硅基三氟乙酰胺(BST-FA)+三甲基氯硅烷(TMCS)为衍生剂,用氘代氯霉素(D5-CAP)为内标物,采用反吹技术,用气相色谱-三重四极杆质谱中多反应监测模式(MRM)进行定性定量分析.该方法在0.5~25 ng范围内线性良好,相关系数r=0.9991,低、高二种浓度加标回收率均在89.2%~106.4%之间,方法检出限为0.1μg/kg.

  2. 分散液液微萃取-高效液相色谱/质谱法测定乳制品中氯霉素含量%Determination of chloramphenicol residue in diary by dispersive liquid-liquid microextraction-liquid chromatography-tandem mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    凌睿; 许磊; 胡文彦

    2013-01-01

    建立了分散液液微萃取-液相色谱/质谱法(DLLME-LC/MS)测定乳制品中氯霉素(CAP)残留的分析方法.采用单次单因子法对影响DLLME富集因子的实验参数进行了优化,试验结果表明,在最优DLLME条件下,方法检测限为0.2/μg/kg,当CAP质量分数在1μg/kg~20μg/kg范围内线性关系良好(R22=0.9961),样品回收率(86%~94%)、方法精密度(2.7%~3.9%)均符合要求,该方法可用于乳制品中CAP残留的检测.

  3. Beneficial effect of Berberis buxifolia Lam, Ziziphus mistol Griseb and Prosopis alba extracts on oxidative stress induced by chloramphenicol Efecto benéfico de extractos de Berberis buxifolia Lam, Zizyphus mistol Griseb y Prosopis alba sobre el estrés oxidativo inducido por cloramfenicol

    Directory of Open Access Journals (Sweden)

    Claudia Albrecht

    2010-02-01

    Full Text Available The chemiluminescence of luminol, a measure of oxidative stress, increased immediately as a consequence of reactive oxygen species (ROS stimulated by this antibiotic. The effect of Ch was dose dependent with maximum stimulus at 8 mg/ml (Vmax; above this concentration the cells began to reduce the production of ROS. The oxidative injury of Ch was counteracted by water extracts of Berberis buxifolia lam, Zizyphus mistol Griseb and Prosopis alba, indigenous fruits from Argentina. The relatively light units (RLU emitted decreased immediately as a consequence of a protective effect exerted by the extracts of these fruit extracts on blood cells. The three indigenous fruit extracts reduced to a different extent the oxidative injury caused by Ch. B.buxifolia lam exhibited the highest antioxidant capacity followed by Z.mistol Griseb. Water extracts of both fruit extracts were the most effective against the oxidative stress, while P.alba presented better antioxidant capacity in the ethanolic fraction obtained. Hexane extracts showed low protective action on blood cells, with little reduction of area under curve (AUC of RLU plotted versus time. Leukocytes remained viable in blood samples incubated for 3h with Ch and water extracts of B. buxifolia lam or Z. mistol Griseb (97.1% and 92.5% viability by Trypan blue exclusion, respectively; whereas with Ch only the cells were stressed and viability decreased to 30%. The three fruit extracts protected the viability of leukocytes in parallel with the decrease of ROS. Erythrocytes were not lysed in the presence of Ch.Se estudió el efecto antioxidante de tres extractos de frutas autóctonas, Berberis buxifolia lam (michay, Zizyphus mistol Griseb (mistol and Prosopis alba (algarrobo. Las células sanguíneas humanas sufrieron estrés oxidativo por acción de cloramfenicol (Ch, con un aumento inmediato de especies reactivas del oxígeno (ERO, que fue determinado por quimioluminiscencia con luminol. La respuesta fue dependiente de la dosis, con un máximo a 8 mg/ml. Los extractos de frutas autóctonas de la Argentina fueron capaces de contrarrestar el estrés generado por el antibiótico. El michay y el mistol resultaron más efectivos en la fase acuosa, y el algarrobo fue más antioxidante en extractos etílicos, mientras que las fracciones obtenidas con hexano no fueron activas. La viabilidad de los leucocitos se mantuvo elevada con Ch en presencia de extractos, entre 92.5 y 97.1%, cayendo hasta un 30% con Ch solo. Tanto los eritrocitos como los leucocitos fueron protegidos del efecto estresante por la capacidad antioxidantes de los extractos de las tres frutas investigadas, lo que podría ser importante a considerar en la dieta de niños, y pacientes en general, sometidos a Ch u otras terapias causantes de estrés oxidativo.

  4. 16S rRNA Gene Sequence and Carbon Metabolic Fingerprint Analysis of a Chloramphenicol Resistant Septic Bacterial Strain Isolated from Cosmetics%1株耐氯霉素腐败微生物的16S rRNA基因序列与碳源代谢指纹图谱分析

    Institute of Scientific and Technical Information of China (English)

    王友升; 何欣萌; 张燕; 陈玉娟

    2014-01-01

    从污染的化妆品中分离到1株具有氯霉素抗性的革兰阴性菌213#.通过16S rRNA基因同源性比较,表明分离菌与GenBank中洋葱伯克霍尔德(Burkholderia cepacia)标准菌株同源性为100%,通过Biolog GN2MicroPlate分析该病原菌对95种碳源的利用能力,发现分离菌与Biolog数据库中的B.cepacia具有最相似的特征代谢指纹.

  5. Determination of Chloramphenicol Antibiotics in Fish Meats by Liquid Chramatography-atmospheric Pressure Pho ot ionization-mass Spectrometry Method%用液相色谱-大气压光离子质谱(LC-APPI-MS)测定鱼肉中的氯霉素

    Institute of Scientific and Technical Information of China (English)

    Masahiko Takino; Shigeki Daishima

    2004-01-01

    用液相色谱-大气压光离子质谱开发出测定鱼肉中的氯霉素抗生素的方法.为优化APPI,考察了几种离子源参数.使用该优化参数,得到了简单的质谱图和对应于[M-H]-的强信号.样品用乙酸乙酯萃取并挥发至干,然后用乙腈和正己烷通过液液分配进行纯化.对于加入量为0.1~2 ng/g的样品,小鲱肉和比目鱼肉中氯霉素的平均回收率分别为89.3%~102.5%和87.4%~94.8%.小鲱肉和比目鱼肉中氯霉素的检测极限(信噪比=3)分别为0.27和0.10ng/g.

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

    Lifescience Database Archive (English)

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

  7. Drug: D00104 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ing sensory organs 131 Ophthalmic agents 1317 Ophthalmic antibiotics D00104 Chloramphenicol (JP16/USP/INN) 1...32 Otic and nasal agents 1325 Otolaryngologic antibiotics D00104 Chloramphenicol ...ERAPEUTICS FOR DERMATOLOGICAL USE D06A ANTIBIOTICS FOR TOPICAL USE D06AX Other antibiotics

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

    Lifescience Database Archive (English)

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

  9. Drug: D01072 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available GICAL ANTIINFECTIVES AND ANTISEPTICS G01A ANTIINFECTIVES AND ANTISEPTICS, EXCL. COMBINATIONS WITH CORTICOSTEROIDS G01AA Antibiotics...GICALS S01A ANTIINFECTIVES S01AA Antibiotics S01AA01 Chloramphenicol D01072 Chloramphenicol palmitate (JP16/

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

    Directory of Open Access Journals (Sweden)

    Andrade Luciana Segura de

    2006-01-01

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

  11. Drug: D04753 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available COMBINATIONS WITH ANTIBIOTICS D07CA Corticosteroids, weak, combinations with antibiotics... D07CA03 Prednisolone and antibiotics D04753 Chloramphenicol - fradiomycin sulfate - prednisolone mixt PubChem: 17398155 ...

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

    DEFF Research Database (Denmark)

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

    2004-01-01

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

  13. Improvement of the tube diffusion test with respect to detection of antibiotic residues and sulphonamides in raw milk

    NARCIS (Netherlands)

    Nouws, J.F.M.; Loeffen, G.; Schouten, J.; Egmond, van H.; Keukens, H.; Stegeman, H.

    1995-01-01

    Improvements in detection of tetracycline, sulphonamide, macrolide, rifamycin, trimethoprim and aminoglycoside residues in milk were achieved by addition of either chloramphenicol or trimethoprim, and phenylbutazone to tube diffusion tests utilising Bacillus stearothermophilus var. calidolactis as b

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

    NARCIS (Netherlands)

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

    2008-01-01

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

  15. The effect of antibiotics on diatom communities

    Digital Repository Service at National Institute of Oceanography (India)

    DeCosta, P.M.; Anil, A.C.

    –100% and favoured emergence of yeast, probably due to high concentrations and synergistic effects. Changes in diatom communities in the individual antibiotic treatments were either direct (chloramphenicol and potentially streptomycin) or bacteria...

  16. Homogeneous sample preparation of raw shrimp using dry ice.

    Science.gov (United States)

    Bunch, E A; Altwein, D M; Johnson, L E; Farley, J R; Hammersmith, A A

    1995-01-01

    Sample homogeneity is critical to accurate and reproducible analysis of trace residues in foods. A method of uniform sample preparation using dry ice is described for shrimp. Other sample preparation techniques for raw shrimp produce nonhomogeneous samples. Sample homogeneity was determined through analysis of chloramphenicol added to intact tiger or white shrimp prior to sample preparation. Simulated chloramphenicol residue levels were 50, 15, 10, and 5 ppb. No significant differences were noted when analyses of shrimp inoculated with chlor-amphenicol prior to sample preparation with dry ice were compared with analyses of shrimp spiked after grinding with dry ice. Grinding shrimp with dry ice produced samples with homogeneous chloramphenicol residues. This technique should be applicable to other tissues and vegetable products.

  17. Thermoanaerobacter mathranii sp. nov., an ethanol-producing, extremely thermophilic anaerobic bacterium from a hot spring in Iceland

    DEFF Research Database (Denmark)

    Larsen, L.; Nielsen, P.; Ahring, B.K.

    1997-01-01

    occurred in the range of 50-75 degrees C. The pH range for growth was 4.7-8.8, with an optimum at pH 7.0. Strain A3 was sensitive to tetracycline, chloramphenicol, penicillin G. neomycin, and vancomycin at 100 mg/l but was not sensitive to chloramphenicol and neomycin at 10 mg/l, which indicates...

  18. Genetics of NAD metabolism in Salmonella typhimurium and cloning of the nadA and pnuC loci.

    OpenAIRE

    TIRGARI, S.; Spector, M P; Foster, J. W.

    1986-01-01

    The nadA and pnuC loci of S. typhimurium were cloned and found to reside within a 2.2-kilobase region. Two-dimensional O'Farrell gel electrophoresis of the proteins produced after chloramphenicol amplification and subsequent release from chloramphenicol inhibition revealed NadA and PnuC to be 43,000- and 25,000-molecular-weight proteins, respectively. The data indicated that nadA and pnuC represent two distinct genes.

  19. Effectiveness of different methods of preparing seedlings of cereals under sterile conditions for investigations of nucleic acids using radioactive precursors

    Directory of Open Access Journals (Sweden)

    W. Filek

    2015-05-01

    Full Text Available On seedlings grown from grain not sterilized in advance bacteria numbered more than 108 microorganisms per one gram of fresh weight. Washing of seedlings with cetyltrimethylammonium bromide or sodium lauryl sulphate solutions reduced the number of bacteria several times. Sterilization of grains prior to planting with sodium hypochlorite and germination on solid substratum (perlit reduced the number of bacteria to below 104 microorganisms to one gram of fresh weight. If germination was, however, in water, bacteria on the seedlings were approximately as numerous as on seedlings from mon-sterilized grains. Of the three antibiotics tested (streptomycin, chloramphenicol, penicillin the most effective against the bacteria of wheat seedlings was chloramphenicol coupled with streptomycin; of antibiotics used singly chloramphenicol was best.

  20. Synergistic activity of coriander oil and conventional antibiotics against Acinetobacter baumannii.

    Science.gov (United States)

    Duarte, A; Ferreira, S; Silva, F; Domingues, F C

    2012-02-15

    In this study we investigated the existence of synergistic antibacterial effect between coriander (Coriandrum sativum L.) essential oil and six different antibacterial drugs (cefoperazone, chloramphenicol, ciprofloxacin, gentamicin, tetracycline and piperacillin). The antibacterial activity of coriander oil was assessed using microdilution susceptibility testing and synergistic interaction by checkerboard assays. The association of coriander essential oil with chloramphenicol, ciprofloxacin, gentamicin and tetracycline against Acinetobacter baumannii showed in vitro effectiveness, which is an indicator of a possible synergistic interaction against two reference strains of A. baumannii (LMG 1025 and LMG 1041) (FIC index from 0.047 to 0.375). However, when tested the involvement between coriander essential oil and piperacillin or cefoperazone, the isobolograms and FIC index showed an additive interaction. The in vitro interaction could improve the antimicrobial effectiveness of ciprofloxacin, gentamicin and tetracycline and may contribute to resensitize A. baumannii to the action of chloramphenicol.

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

    DEFF Research Database (Denmark)

    Douthwaite, S

    1992-01-01

    A molecular genetic approach has been employed to investigate functional interactions within 23S rRNA. Each of the three base substitutions at guanine 2032 has been made. The 2032A mutation confers resistance to the antibiotics chloramphenicol and clindamycin, which interact with the 23S r...... that also confer antibiotic resistance. Both the domain II deletion and the 2057A mutation relieve the hypersensitive effect of the 2032A mutation, producing an erythromycin-resistant phenotype; in addition, the combination of the 2032A and 2057A mutations confers a higher level of chloramphenicol...... and chloramphenicol. Introduction of the domain II deletion into these double-mutation constructs gives rise to erythromycin resistance. The results are interpreted as indicating that position 2032 interacts with the peptidyltransferase loop and that there is a functional connection between domains II and V....

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

    Indian Academy of Sciences (India)

    Bahman Zeynali; Keith E Dixon

    2004-09-01

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

  3. Antimicrobial susceptibility testing of Haemophilus parainfluenzae by a kinetic killing-curve method.

    Science.gov (United States)

    Jemsek, J G; Martin, R R; Greenberg, S B; Gentry, L O

    1980-03-01

    A kinetic killing-curve method, designed to mimic several aspects of clinical therapy in endocarditis, was used to test 10 strains of Haemophilus parainfluenzae against 28 antibiotic regimens. In an effort to simulate changing in vivo levels of antibiotic in serum, concentrations of three penicillins, three cephalosporins, gentamicin, and chloramphenicol were sequentially adjusted over a 12-hr period. Against six beta-lactamase-negative strains, gentamicin in combination with penicillin or cephalosporin invariably resulted in an additive or synergistic effect. Chloramphenicol and a penicillin or cephalosporin usually displayed an indifferent effect, but chloramphenicol was often antagonistic when combined with gentamicin. With four beta-lactamase-positive strains, variable responses were noted to penicillin-aminoglycoside combinations; cephalosporin-aminoglycoside combinations were usually synergistic. This dynamic approach to killing-curve studies may be more appropriate than a static system for in vitro examination of the effect of antimicrobial combinations against selected organisms.

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

    Directory of Open Access Journals (Sweden)

    Krishnan Padma

    2009-10-01

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

  5. Structure of the replicative form of bacteriophage φX174 : VI. Studies on alkali-denatured double-stranded φX DNA

    NARCIS (Netherlands)

    Pouwels, P.H.; Knijnenburg, C.M.; Rotterdam, J. van; Cohen, J.A.; Jansz, H.S.

    1968-01-01

    Double-stranded φX DNA which accumulates after infection with bacteriophage φX174 in the presence of chloramphenicol consists mainly of twisted circular double-stranded DNA with no single-strand breaks (component I) and of circular double-stranded DNA, in which single-strand breaks are present (comp

  6. Translocation of integron-associated resistance in a natural system: Acquisition of resistance determinants by Inc P and Inc W Plasmids from Salmonella enterica Typhimurium DT104

    DEFF Research Database (Denmark)

    Sandvang, Dorthe; Diggle, M.; Platt, D.J.

    2002-01-01

    Salmonella enterica Typhimurium DT104, 961368, a veterinary field isolate that encodes a chromosomal cluster of resistance genes as well as two integrons, was used to study the mobility of resistance cassettes (aadA2 and pse-1) and nonintegron-associated resistance determinants (chloramphenicol...

  7. Fabrication of SERS-active substrates using silver nanofilm-coated porous anodic aluminum oxide for detection of antibiotics.

    Science.gov (United States)

    Chen, Jing; Feng, Shaolong; Gao, Fang; Grant, Edward; Xu, Jie; Wang, Shuo; Huang, Qian; Lu, Xiaonan

    2015-04-01

    We have developed a silver nanofilm-coated porous anodic aluminum oxide (AAO) as a surface-enhanced Raman scattering (SERS)-active substrate for the detection of trace level of chloramphenicol, a representative antibiotic in food systems. The ordered aluminum template generated during the synthesis of AAO serves as a patterned matrix on which a coated silver film replicates the patterned AAO matrix to form a 2-dimensional ordered nanostructure. We used atomic force microscopy and scanning electron microscopy images to determine the morphology of this nanosubstrate, and characterized its localized surface plasmon resonance by ultraviolet-visible reflection. We gauged the SERS effect of this nanosubstrate by confocal micro-Raman spectroscopy (782-nm laser), finding a satisfactory and consistent performance with enhancement factors of approximately 2 × 10(4) and a limit of detection for chloramphenicol of 7.5 ppb. We applied principal component analysis to determine the limit of quantification for chloramphenicol of 10 ppb. Using electromagnetic field theory, we developed a detailed mathematical model to explain the mechanism of Raman signal enhancement of this nanosubstrate. With simple sample pretreatment and separation steps, this silver nanofilm-coated AAO substrate could detect 50 ppb chloramphenicol in milk, indicating good potential as a reliable SERS-active substrate for rapid detection of chemical contaminants in agricultural and food products.

  8. Lethal traffic jam

    NARCIS (Netherlands)

    Breukink, E.J.

    2009-01-01

    The antibiotics chloramphenicol and tetracycline were discovered in the late 1940s shortly after the introduction of penicillin (1). Elucidation of the structure of the ribosome (2, 3) revealed how they bind to this target structure and inhibit protein synthesis. On page 753 in this issue, van Stelt

  9. An in vitro study on the effects of nisin on the antibacterial activities of 18 antibiotics against Enterococcus faecalis.

    Science.gov (United States)

    Tong, Zhongchun; Zhang, Yuejiao; Ling, Junqi; Ma, Jinglei; Huang, Lijia; Zhang, Luodan

    2014-01-01

    Enterococcus faecalis rank among the leading causes of nosocomial infections worldwide and possesses both intrinsic and acquired resistance to a variety of antibiotics. Development of new antibiotics is limited, and pathogens continually generate new antibiotic resistance. Many researchers aim to identify strategies to effectively kill this drug-resistant pathogen. Here, we evaluated the effect of the antimicrobial peptide nisin on the antibacterial activities of 18 antibiotics against E. faecalis. The MIC and MBC results showed that the antibacterial activities of 18 antibiotics against E. faecalis OG1RF, ATCC 29212, and strain E were significantly improved in the presence of 200 U/ml nisin. Statistically significant differences were observed between the results with and without 200 U/ml nisin at the same concentrations of penicillin or chloramphenicol (pnisin and penicillin or chloramphenicol had a synergetic effect against the three tested E. faecalis strains. The transmission electron microscope images showed that E. faecalis was not obviously destroyed by penicillin or chloramphenicol alone but was severely disrupted by either antibiotic in combination with nisin. Furthermore, assessing biofilms by a confocal laser scanning microscope showed that penicillin, ciprofloxacin, and chloramphenicol all showed stronger antibiofilm actions in combination with nisin than when these antibiotics were administered alone. Therefore, nisin can significantly improve the antibacterial and antibiofilm activities of many antibiotics, and certain antibiotics in combination with nisin have considerable potential for use as inhibitors of this drug-resistant pathogen.

  10. Polyclonal KPC-3-producing Enterobacteriaceae in Portugal

    OpenAIRE

    Manageiro, Vera; Ferreira, Eugénia; Louro, Deolinda; Caniça, Manuela; Antimicrobial Resistance Surveillance Program in Portugal (ARSIP)

    2012-01-01

    Water has been recognized as a reservoir for antibiotic resistance genes (ARG), where the presence of mobile genetic elements, including plasmids, favors their dissemination. It is noteworthy that nonpathogenic environmental organisms, where plasmids encoding multiple ARG are prevalent, can provide resistance to most classes of antimicrobials including beta-lactams, aminoglycosides, chloramphenicol, trimethoprim, streptomycin, fosfomycin, quinolones, among others. The main goal of...

  11. Multidrug resistance among different serotypes of clinical Salmonella isolates in Taiwan

    DEFF Research Database (Denmark)

    Lauderdale, T. L.; Aarestrup, Frank Møller; Chen, P. C.;

    2006-01-01

    Of the 798 clinical Salmonella isolates collected from multiple hospitals in Taiwan, resistance to ampicillin (48.5%), chloramphenicol (55.3%), streptomycin (59.0%), sulfamethoxazole (68.0%), and tetracycline (67.8%) was high, whereas resistance to all 5 antimicrobials (ACSSuT R-type) comprised 3...

  12. A novel case of chronic conjunctivitis in a 58-year-old woman caused by Raoultella.

    Science.gov (United States)

    Zuberbuhler, B; Abedin, A; Roudsari, A

    2014-10-01

    A 58-year-old woman presented to eye emergency with a chronic conjunctivitis which was diagnosed by laboratory microbiological testing to be due to the environmental pathogen Raoultella planticola. The organism was sensitive to Chloramphenicol and the patient made a rapid recovery on these drops. This is the first report of this organism infecting the eye.

  13. Clonal occurrence of Salmonella Weltevreden in cultured shrimp in the Mekong Delta, Vietnam

    DEFF Research Database (Denmark)

    Uddin, Gazi Md Noor; Larsen, Marianne Halberg; Barco, Lisa;

    2015-01-01

    . Weltevreden was susceptible to most antimicrobials tested, with a few strains being resistant to florfenicol, chloramphenicol, sulfamethoxazole or trimethoprim. Future studies of the ecology of S. Weltevreden should establish if this serovar may survive better and even multiply in warm-water shrimp farm...

  14. Periconceptional and Gestational Exposure to Antibiotics and Childhood Asthma.

    Directory of Open Access Journals (Sweden)

    Shuyuan Chu

    Full Text Available Previous studies suggest that maternal antibiotics exposure during pregnancy may increase the risk of childhood asthma, but the results were inconsistent. Furthermore, most studies did not examine periconception period as an exposure window. We aim to assess the associations between maternal exposure to specific antibiotics before and during pregnancy and the risk of asthma in early childhood.Data from the Collaborative Perinatal Project were used. Maternal exposure to antibiotics before and during pregnancy was recorded at each prenatal visit. A total of 39,907 singleton children were followed up to 7 years of age. Multilevel multiple logistic regression models were used to control for potential confounders and account for multiple pregnancies per woman.Maternal use of penicillin or chloramphenicol was associated with an increased risk of asthma in the offspring (adjusted odds ratio = 1.21, 95% confidence interval 1.08-1.36 for penicillin; 1.72 [1.14-2.59] for chloramphenicol. The risk was significantly increased if penicillin or chloramphenicol was used in the 1st trimester (1.09 [1.04-1.13] for penicillin and 1.23 [1.01-1.51] for chloramphenicol.Maternal exposure to certain antibiotics is associated with childhood asthma by 7 years of age. Early pregnancy may be a sensitive window.

  15. Microbiologic and Clinical Features of Salmonella Species Isolated From Bacteremic Children in Eastern Democratic Republic of Congo

    DEFF Research Database (Denmark)

    Vandenberg, Olivier; Nyarukweba, Deo Z.; Ndeba, Prudence M.

    2010-01-01

    typhimurium (60.5%) and Salmonella enteritidis (22.3%) were the most common Salmonella serotypes. In total, 92.4% were resistant to at least 3 antimicrobials with the following proportion of strains resistant to: ampicillin (86%), chloramphenicol (92%), trimethoprim/sulfamethoxazole (95%), and tetracycline...

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

    NARCIS (Netherlands)

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

    2001-01-01

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

  17. Production of Axenic Gonyaulax Cultures by Treatment with Antibiotics

    OpenAIRE

    1982-01-01

    The effects of amphotericin B, chloramphenicol, dihydrostreptomycin sulfate, neomycin sulfate, polymyxin B sulfate, potassium penicillin G, and streptomycin sulfate (used singularly and in various combinations at different concentrations) on the growth and development of four marine dinoflagellates of the genus Gonyaulax and associated bacteria were studied. The combination of amphotericin B, dihydrostreptomycin, neomycin, and penicillin G was highly effective in eliminating bacteria and fung...

  18. Life-Threatening Infantile Diarrhea from Fluoroquinolone-Resistant Salmonella enteric Typhimurium with Mutations in Both gyrA and parC

    OpenAIRE

    Nakaya, Hideo; Yasuhara, Akihiro; Yoshimura, Ken; Oshihoi, Yukio; Izumiya, Hidemasa; Watanabe, Haruo

    2003-01-01

    Salmonella Typhimurium DT12, isolated from a 35-day-old infant with diarrhea, was highly resistant to ampicillin, tetracycline, chloramphenicol, streptomycin, gentamycin, sulfamethoxazole/trimethoprim, nalidixic acid, and fluoroquinolones. The patient responded to antibiotic therapy with fosfomycin. Multidrug-resistance may become prevalent in Salmonella infections in Japan, as shown in this first case of a patient infected with fluoroquinolone-resistant Salmonella.

  19. Heme regulates the expression in Saccharomyces cerevisiae of chimaeric genes containing 5'-flanking soybean leghemoglobin sequences

    DEFF Research Database (Denmark)

    Jensen, E O; Marcker, K A; Villadsen, IS

    1986-01-01

    The TM1 yeast mutant was transformed with a 2 micron-derived plasmid (YEp24) which carries a chimaeric gene containing the Escherichia coli chloramphenicol acetyl transferase (CAT) gene fused to the 5'- and 3'-flanking regions of the soybean leghemoglobin (Lb) c3 gene. Expression of the chimaeric...

  20. Genome engineering using a synthetic gene circuit in Bacillus subtilis.

    Science.gov (United States)

    Jeong, Da-Eun; Park, Seung-Hwan; Pan, Jae-Gu; Kim, Eui-Joong; Choi, Soo-Keun

    2015-03-31

    Genome engineering without leaving foreign DNA behind requires an efficient counter-selectable marker system. Here, we developed a genome engineering method in Bacillus subtilis using a synthetic gene circuit as a counter-selectable marker system. The system contained two repressible promoters (B. subtilis xylA (Pxyl) and spac (Pspac)) and two repressor genes (lacI and xylR). Pxyl-lacI was integrated into the B. subtilis genome with a target gene containing a desired mutation. The xylR and Pspac-chloramphenicol resistant genes (cat) were located on a helper plasmid. In the presence of xylose, repression of XylR by xylose induced LacI expression, the LacIs repressed the Pspac promoter and the cells become chloramphenicol sensitive. Thus, to survive in the presence of chloramphenicol, the cell must delete Pxyl-lacI by recombination between the wild-type and mutated target genes. The recombination leads to mutation of the target gene. The remaining helper plasmid was removed easily under the chloramphenicol absent condition. In this study, we showed base insertion, deletion and point mutation of the B. subtilis genome without leaving any foreign DNA behind. Additionally, we successfully deleted a 2-kb gene (amyE) and a 38-kb operon (ppsABCDE). This method will be useful to construct designer Bacillus strains for various industrial applications.

  1. Synthesis and biological activity of nifuroxazide and analogs.

    Science.gov (United States)

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

    1997-03-01

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

  2. Molecular Analysis of Bacterial Community Dynamics During Bioaugmentation Studies in a Soil Column and at a Field Test Site

    Science.gov (United States)

    2007-11-02

    gelatin or bovine serum albumin (BSA), primers and target DNAs (Taylor, 1991). DNA polymerases carry out the synthesis of a complementary strand of DNA...Samples Treated with Chloramphenicol. Appli. Environ. Microbiol. 63:2735-2740. Ouverney, C. C. and J. A. Fuhrman. 2000. Marine Planktonic Archaea

  3. Transcriptional activation by the E1A regions of adenovirus types 40 and 41

    NARCIS (Netherlands)

    Loon, A.E. van; Gilardi, P.; Perricaudet, M.; Rozijn, Th. H.; Sussenbach, J.S.

    1987-01-01

    In order to establish whether the poor growth of the two fastidious adenoviruses types 40 and 41 (Ad40 and Ad41) in HeLa cells is due to a reduced trans-activation by the early region to (E1A), we have determined the trans-activating effect of this region on the expression of the chloramphenicol ace

  4. Medication for Military Aircrew: Current Use, Issues, and Strategies for Expanded Options (les medicaments pour les equipaes militaires: Consommation actuelle, questions et strategies pour des options elargies)

    Science.gov (United States)

    2001-06-01

    niacin 5. Optic nerve – toxic optic neuropathy - ethambutol, chloramphenicol, lithium Testing Visual Function Baseline testing is crucial, since early...from direct damage of the myocardium by the drug, such as with antineoplastic drugs, emetine, phenothiazines, lithium , or sympathomimetics, or due to...failure and diabetic nephropathy . Besides blocking the conversion of angiotensin I, ACE inhibitors also prevent the degradation of bradykinin and

  5. [Transmissivity of antibiotic resistance factors in intergeneric crossing of salmonellae and Escherichia Crimea].

    Science.gov (United States)

    Kharchenko, G I; Zadorina, T M; Belova, N N

    1981-11-01

    The results of the crosses between Salmonella and Escherichia 0151C are presented. Transmissive determinants resistant to ampicillin, dentamicin, kanamycin, neomycin, monomycin, streptomycin, morphocyclin, tetracycline and chloramphenicol were detected. It was shown that almost 50 per cent of Escherichia 0151K except the transmissive R factors were able to transferring the colicinogenic determinants.

  6. Antibiotic Resistant Salmonella and Vibrio Associated with Farmed Litopenaeus vannamei

    OpenAIRE

    Sanjoy Banerjee; Mei Chen Ooi; Mohamed Shariff; Helena Khatoon

    2012-01-01

    Salmonella and Vibrio species were isolated and identified from Litopenaeus vannamei cultured in shrimp farms. Shrimp samples showed occurrence of 3.3% of Salmonella and 48.3% of Vibrio. The isolates were also screened for antibiotic resistance to oxolinic acid, sulphonamides, tetracycline, sulfamethoxazole/trimethoprim, norfloxacin, ampicillin, doxycycline hydrochloride, erythromycin, chloramphenicol, and nitrofurantoin. Salmonella enterica serovar Corvallis isolated from shrimp showed indiv...

  7. Drug: D02185 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ologic organisms and parasites 61 Antibiotics 615 Acting mainly on gram-positive bacteria, gram-negative bac...NTISEPTICS, EXCL. COMBINATIONS WITH CORTICOSTEROIDS G01AA Antibiotics G01AA05 Chloramphenicol D02185 Chloram...sodium succinate (JP16/USP) S SENSORY ORGANS S01 OPHTHALMOLOGICALS S01A ANTIINFECTIVES S01AA Antibiotics S01

  8. Unique plasmids generated via pUC replicon mutagenesis in an error-prone thermophile derived from Geobacillus kaustophilus HTA426.

    Science.gov (United States)

    Kobayashi, Jyumpei; Tanabiki, Misaki; Doi, Shohei; Kondo, Akihiko; Ohshiro, Takashi; Suzuki, Hirokazu

    2015-11-01

    The plasmid pGKE75-catA138T, which comprises pUC18 and the catA138T gene encoding thermostable chloramphenicol acetyltransferase with an A138T amino acid replacement (CATA138T), serves as an Escherichia coli-Geobacillus kaustophilus shuttle plasmid that confers moderate chloramphenicol resistance on G. kaustophilus HTA426. The present study examined the thermoadaptation-directed mutagenesis of pGKE75-catA138T in an error-prone thermophile, generating the mutant plasmid pGKE75(αβ)-catA138T responsible for substantial chloramphenicol resistance at 65°C. pGKE75(αβ)-catA138T contained no mutation in the catA138T gene but had two mutations in the pUC replicon, even though the replicon has no apparent role in G. kaustophilus. Biochemical characterization suggested that the efficient chloramphenicol resistance conferred by pGKE75(αβ)-catA138T is attributable to increases in intracellular CATA138T and acetyl-coenzyme A following a decrease in incomplete forms of pGKE75(αβ)-catA138T. The decrease in incomplete plasmids may be due to optimization of plasmid replication by RNA species transcribed from the mutant pUC replicon, which were actually produced in G. kaustophilus. It is noteworthy that G. kaustophilus was transformed with pGKE75(αβ)-catA138T using chloramphenicol selection at 60°C. In addition, a pUC18 derivative with the two mutations propagated in E. coli at a high copy number independently of the culture temperature and high plasmid stability. Since these properties have not been observed in known plasmids, the outcomes extend the genetic toolboxes for G. kaustophilus and E. coli.

  9. Identification of a novel G2073A mutation in 23S rRNA in amphenicol-selected mutants of Campylobacter jejuni.

    Directory of Open Access Journals (Sweden)

    Licai Ma

    Full Text Available OBJECTIVES: This study was conducted to examine the development and molecular mechanisms of amphenicol resistance in Campylobacter jejuni by using in vitro selection with chloramphenicol and florfenicol. The impact of the resistance development on growth rates was also determined using in vitro culture. METHODS: Chloramphenicol and florfenicol were used as selection agents to perform in vitro stepwise selection. Mutants resistant to the selective agents were obtained from the selection process. The mutant strains were compared with the parent strain for changes in MICs and growth rates. The 23S rRNA gene and the L4 and L22 ribosomal protein genes in the mutant strains and the parent strain were amplified and sequenced to identify potential resistance-associated mutations. RESULTS: C. jejuni strains that were highly resistant to chloramphenicol and florfenicol were obtained from in vitro selection. A novel G2073A mutation in all three copies of the 23S rRNA gene was identified in all the resistant mutants examined, which showed resistance to both chloramphenicol and florfenicol. In addition, all the mutants selected by chloramphenicol also exhibited the G74D modification in ribosomal protein L4, which was previously shown to confer a low-level erythromycin resistance in Campylobacter species. The mutants selected by florfenicol did not have the G74D mutation in L4. Notably, the amphenicol-resistant mutants also exhibited reduced susceptibility to erythromycin, suggesting that the selection resulted in cross resistance to macrolides. CONCLUSIONS: This study identifies a novel point mutation (G2073A in 23S rRNA in amphenicol-selected mutants of C. jejuni. Development of amphenicol resistance in Campylobacter likely incurs a fitness cost as the mutant strains showed slower growth rates in antibiotic-free media.

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

    Science.gov (United States)

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

    2016-05-01

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

  11. Purification and characterization of a 4-hydroxybiphenyl UDP-glucuronosyltransferase from rat liver microsomes

    Energy Technology Data Exchange (ETDEWEB)

    Styczynski, B.; Green, M.; Coffman, B.; Puig, J.; Tephly, T. (Univ. of Iowa, Iowa City (United States))

    1991-03-11

    A phenobarbital-inducible rat liver microsomal UDP-glucuronosyltransferase (4-HBP UDPGT) which catalyzes the glucuronidation of 4-hydroxybiphenyl has been purified to homogeneity. The apparent subunit molecular weight of this protein is 52,500 as determined by SDS-PAGE. 4-HBP UDPGT was shown to react with 4-hydroxybiphenyl, p-nitrophenol and 4-methylumbelliferone, but did not react with morphine, testosteron or chloramphenicol. Upon treatment with Endoglycosidase H, the 4-HBP UDPGT underwent about a 2,000 dalton decrease in subunit molecular weight, suggesting that this protein in N-glycosylated. Western blot analysis has revealed immunorecognition of 4-HBP UDPGT by antibodies raised in rabbit against rat 3{alpha}- and 17{beta}-hydroxysteroid UDPGTs. Additionally, the authors have obtained the N-terminal amino acid sequence of 4-HBP UDPGT. These data provide evidence which suggests that this protein is different from another UDPGT previously shown to react with 4-hydroxybiphenyl, testosterone and chloramphenicol.

  12. Synthesis and evaluation of hetero- and homodimers of ribosome-targeting antibiotics: antimicrobial activity, in vitro inhibition of translation, and drug resistance.

    Science.gov (United States)

    Berkov-Zrihen, Yifat; Green, Keith D; Labby, Kristin J; Feldman, Mark; Garneau-Tsodikova, Sylvie; Fridman, Micha

    2013-07-11

    In this study, we describe the synthesis of a full set of homo- and heterodimers of three intact structures of different ribosome-targeting antibiotics: tobramycin, clindamycin, and chloramphenicol. Several aspects of the biological activity of the dimeric structures were evaluated including antimicrobial activity, inhibition of in vitro bacterial protein translation, and the effect of dimerization on the action of several bacterial resistance mechanisms that deactivate tobramycin and chloramphenicol. This study demonstrates that covalently linking two identical or different ribosome-targeting antibiotics may lead to (i) a broader spectrum of antimicrobial activity, (ii) improved inhibition of bacterial translation properties compared to that of the parent antibiotics, and (iii) reduction in the efficacy of some drug-modifying enzymes that confer high levels of resistance to the parent antibiotics from which the dimers were derived.

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

    Institute of Scientific and Technical Information of China (English)

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

    2007-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Funso Omojowo

    2013-02-01

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

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

    Institute of Scientific and Technical Information of China (English)

    Prakash S; S Anto Jeya Dayalan; Edison N

    2011-01-01

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

  16. Quinazoline derivatives are efficient chemosensitizers of antibiotic activity in Enterobacter aerogenes, Klebsiella pneumoniae and Pseudomonas aeruginosa resistant strains.

    Science.gov (United States)

    Chevalier, Jacqueline; Mahamoud, Abdallah; Baitiche, Milad; Adam, Elissavet; Viveiros, Miguel; Smarandache, Adriana; Militaru, Andra; Pascu, Mihail L; Amaral, Leonard; Pagès, Jean-Marie

    2010-08-01

    Amongst the three series of quinazoline derivatives synthesised and studied in this work, some molecules increase the antibiotic susceptibility of Gram-negative bacteria presenting multidrug-resistant phenotypes. N-alkyl compounds induced an increase in the activity of chloramphenicol, nalidixic acid and sparfloxacin, which are substrates of the AcrAB-TolC and MexAB-OprM efflux pumps in clinical isolates. These molecules are able to increase the intracellular concentration of chloramphenicol in efflux pump-overproducing strains. Their activity depends on the antibiotic structure, suggesting that different sites may be involved for the recognition of substrates by a given efflux pump. Quinazoline molecules exhibiting a nitro functional group are more active, and structure-activity relationship studies may be undertaken to identify the pharmacophoric group involved in the AcrB and MexB affinity sites.

  17. Synergistic antibacterial activity of Salvia officinalis and Cichorium intybus extracts and antibiotics.

    Science.gov (United States)

    Stefanović, Olgica D; Stanojević, Dragana D; Comić, Ljiljana R

    2012-01-01

    Synergistic activity of Salvia officinalis and Cichorium intybus extracts and commonly used antibiotics, amoxicillin and chloramphenicol, were evaluated. Interactions between plant extracts and antibiotics were tested by checkerboard method and interpreted as FIC index. Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and clinical isolates Staphylococcus aureus, Bacillus subtilis, Enterobacter cloacae, Klebsiella pneumoniae, Escherichia coli and Proteus mirabilis were used. Salvia officinalis showed better synergistic capacity than Cichorium intybus. Synergistic interactions were observed between amoxicillin and acetone or ethyl acetate extract of Salvia officinalis and between chloramphenicol and ethyl acetate extract of Salvia officinalis. In the presence of sub-inhibitory concentration (1/4 MIC to 1/32 MIC) of sage extracts, the MIC values of antibiotics were decreased by 2- to 10-fold. Synergism was observed against all test bacteria, except Escherichia coli. The combinations of acetone and ethyl acetate extract from Cichorium intybus and antibiotics resulted in additive and indifferent effects against tested bacteria.

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

    Directory of Open Access Journals (Sweden)

    Kaskhedikar

    2009-02-01

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

  19. Antimicrobial susceptibility of Staphylococcus aureus and Staphylococcus pseudintermedius isolated from various animals.

    Science.gov (United States)

    Rubin, Joseph E; Ball, Katherine R; Chirino-Trejo, Manuel

    2011-02-01

    This study characterized the antimicrobial susceptibility of 221 Staphylococcus aureus isolated from various species, and 60 canine Staphylococcus pseudintermedius isolated from 1986 through 2000 at the Western College of Veterinary Medicine (WCVM). Resistance of S. aureus was most common to penicillin (31%) and tetracycline (14%); resistance of S. pseudintermedius to penicillin was present in 8% and to tetracycline in 34% of isolates. Resistance to trimethoprim/sulfamethoxazole was only seen among S. pseudintermedius, and there was no resistance to amoxicillin/clavulanate, ampicillin/sulbactam, cephalothin, amikacin, gentamicin, enrofloxacin, chloramphenicol, or rifampin among any isolate. Inducible clindamycin resistance was found in both S. aureus and S. pseudintermedius, highlighting the need for careful interpretation of culture and susceptibility test results. There were significant differences in the minimum inhibitory concentrations of penicillin, ciprofloxacin, enrofloxacin, clindamycin, erythromycin, chloramphenicol, and tetracycline between avian, bovine, equine, and porcine isolates.

  20. The In Vitro Antimicrobial Effects of Lavandula angustifolia Essential Oil in Combination with Conventional Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Stephanie de Rapper

    2016-01-01

    Full Text Available The paper focuses on the in vitro antimicrobial activity of Lavandula angustifolia Mill. (lavender essential oil in combination with four commercial antimicrobial agents. Stock solutions of chloramphenicol, ciprofloxacin, nystatin, and fusidic acid were tested in combination with L. angustifolia essential oil. The antimicrobial activities of the combinations were investigated against the Gram-positive bacterial strain Staphylococcus aureus (ATCC 6538 and Gram-negative Pseudomonas aeruginosa (ATCC 27858 and Candida albicans (ATCC 10231 was selected to represent the yeasts. The antimicrobial effect was performed using the minimum inhibitory concentration (MIC microdilution assay. Isobolograms were constructed for varying ratios. The most prominent interaction was noted when L. angustifolia essential oil was combined with chloramphenicol and tested against the pathogen P. aeruginosa (ΣFIC of 0.29. Lavendula angustifolia essential oil was shown in most cases to interact synergistically with conventional antimicrobials when combined in ratios where higher volumes of L. angustifolia essential oil were incorporated into the combination.

  1. Molecular mechanism of null expression of aldehyde dehydrogenase-1 in rat liver

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J.; Yoshida, Akira [Institute of the City of Hope, Duarte, CA (United States); Yanagawa, Yuchio [Tokohu Univ., Sendai (Japan)

    1996-04-01

    In isozyme systems in general, the pattern of tissue-dependent expression of a given type of isozyme is uniform in various mammalian species. In contrast, a major cytosolic aldehyde dehydrogenase isozyme, termed ALDH1, which is strongly expressed in the livers of humans and other mammals, is hardly detectable in rat liver. Thirteen nucleotides existing in the 5{prime}-promoter region of human, marmoset, and mouse ALDH1 genes are absent in the four rat strains examined. When the 13 nucleotides were deleted from a chloramphenicol acetyltransferase expression construct, which contained the 5{prime} promoter region of the human ALDH1 gene and a low-background promoterless chloramphenicol acetyltransferase expression vector, the expression activity was severely diminished in human hepatic cells. Thus, deletion of the 13 nucleotides in the promoter region of the gene can account for the lack of ALDH1 expression in rat liver. 16 refs., 3 figs.

  2. Construction of two selectable markers for integrative/conjugative plasmids in Flavobacterium columnare

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jin; ZOU Hong; WANG Liangfa; HUANG Bei; LI Nan; WANG Guitang; NIE Pin

    2012-01-01

    Flavobacterium columnare,the etiological agent of columnaris disease,is one of the most important and widespread bacterial pathogens of freshwater fish.In this study,we constructed two artificial selectable markers (chloramphenicol and spectinomycin resistance) for gene transfer in F.columnare.These two new artificial selectable markers,which were created by placing the chloramphenicol or spectinomycin resistance gene under the control of the native acs regulatory region of F.columnare,were functional in both F.columnare and Escherichia coli.The integrative/conjugative plasmids constructed by using these markers were introduced into F.columnare G4 via electroporation or conjugation.The integrated plasmid DNA was confirmed by Southem blotting and PCR analysis.These two markers can be employed in future investigations into gene deletion and the pathogenicity of virulence factors in F.columnare.

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

    Directory of Open Access Journals (Sweden)

    Ligia Maria Bedeschi Costa

    2013-06-01

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

  4. High level multiple antibiotic resistance among fish surface associated bacterial populations in non-aquaculture freshwater environment.

    Science.gov (United States)

    Ozaktas, Tugba; Taskin, Bilgin; Gozen, Ayse G

    2012-12-01

    Freshwater fish, Alburnus alburnus (bleak), were captured from Lake Mogan, situated in Ankara, during spring. The surface mucus of the fish was collected and associated bacteria were cultured and isolated. By sequencing PCR-amplified 16S RNA encoding genes, the isolates were identified as members of 12 different genera: Acinetobacter, Aeromonas, Bacillus, Brevundimonas, Gordonia, Kocuria, Microbacterium, Mycobacterium, Pseudomonas, Rhodococcus, and Staphylococcus, in addition to one strain that was unidentified. The mucus-dwelling bacterial isolates were tested for resistance against ampicillin, kanamycin, streptomycin and chloramphenicol. About 95% of the isolates were found to be resistant to ampicillin, 93% to chloramphenicol, and 88% to kanamycin and streptomycin. A Microbacterium oxydans and the unidentified environmental isolate were resistant to all four antibiotics tested at very high levels (>1600 μg/ml ampicillin and streptomycin; >1120 μg/ml kanamycin; >960 μg/ml chloramphenicol). Only a Kocuria sp. was sensitive to all four antibiotics at the lowest concentrations tested (3.10 μg/ml ampicillin and streptomycin; 2.15 μg/ml kanamycin; 1.85 μg/ml chloramphenicol). The rest of the isolates showed different resistance levels. Plasmid isolations were carried out to determine if the multiple antibiotic resistance could be attributed to the presence of plasmids. However, no plasmid was detected in any of the isolates. The resistance appeared to be mediated by chromosome-associated functions. This study indicated that multiple antibiotic resistance at moderate to high levels is common among the current phenotypes of the fish mucus-dwelling bacterial populations in this temperate, shallow lake which has not been subjected to any aquaculturing so far but under anthropogenic effect being in a recreational area.

  5. In vitro susceptibility of Haemophilus equigenitalis, the causative organism of contagious equine metritis 1977, to antimicrobial agents.

    OpenAIRE

    DABERNAT, H.J.; Delmas, C F; Tainturier, D J; Lareng, M B

    1980-01-01

    The in vitro susceptibility of recent clinical isolates of Haemophilus equigenitalis to various antimicrobial agents was determined by the disk diffusion test and the World Health Organization-International Collaborative Study agar dilution procedure. Ampicillin and tetracycline were the most active drugs. All strains were susceptible to beta-lactam antibiotics, chloramphenicol, trimethoprim-sulfamethoxazole, nalidixic acid, nitrofurantoin (Furadantin), and bacitracin. All but two strains wer...

  6. Role of signal peptides in targeting of proteins in cyanobacteria.

    OpenAIRE

    Mackle, M M; Zilinskas, B A

    1994-01-01

    Proteins of cyanobacteria may be transported across one of two membrane systems: the typical eubacterial cell envelope (consisting of an inner membrane, periplasmic space, and an outer membrane) and the photosynthetic thylakoids. To investigate the role of signal peptides in targeting in cyanobacteria, Synechococcus sp. strain PCC 7942 was transformed with vectors carrying the chloramphenicol acetyltransferase reporter gene fused to coding sequences for one of four different signal peptides. ...

  7. POLA PEMBERIAN ANTIBIOTIKA PENGOBATAN DEMAM TIFOID ANAK DI RUMAH SAKIT FATMAWATI JAKARTA TAHUN 2001 – 2002

    Directory of Open Access Journals (Sweden)

    Ascobat Gani

    2004-06-01

    Full Text Available The Pattern of the Use of Antibiotics in the Treatment of Children with Typhoid Fever in Fatmawati Hospital Jakarta, 2001-2002. This study was a retrospective study using a descriptive design on the treatment of typhoid fever involving 182 children at Fatmawati Hospital Jakarta. Chloramphenicol was still the drug of choice againts Salmolella typhi. It was also shown that ceftriaxone was an alternative drug used rather frequently for typhoid fever in children.

  8. Skin Infection due to Trichophyton tonsurans Still Occurs in People in Korea but not as Outbreaks

    OpenAIRE

    Lee, Weon Ju; Sim, Hyun Bo; Jang, Yong Hyun; Lee, Seok-Jong; Kim, Do Won; Jun, Jae Bok; Bang, Yong Jun

    2016-01-01

    Since 1995, Trichophyton tonsurans has been one of the causative agents of dermatophytosis in Korea. Herein we evaluate 77 patients infected with T. tonsurans who visited an outpatient clinic between 2004 and 2014. Infections due to T. tonsurans were diagnosed by mycological examination, which included direct microscopic examination using 15% KOH and culture in potato dextrose agar complemented with 0.5% chloramphenicol. The annual prevalence of infection due to T. tonsurans was the highest i...

  9. Transposon Insertion Reveals pRM, a Plasmid of Rickettsia monacensis▿

    OpenAIRE

    Baldridge, Gerald D.; Burkhardt, Nicole Y.; Felsheim, Roderick F.; Timothy J Kurtti; Munderloh, Ulrike G.

    2007-01-01

    Until the recent discovery of pRF in Rickettsia felis, the obligate intracellular bacteria of the genus Rickettsia (Rickettsiales: Rickettsiaceae) were thought not to possess plasmids. We describe pRM, a plasmid from Rickettsia monacensis, which was detected by pulsed-field gel electrophoresis and Southern blot analyses of DNA from two independent R. monacensis populations transformed by transposon-mediated insertion of coupled green fluorescent protein and chloramphenicol acetyltransferase m...

  10. Antibiotic resistance of Staphylococcus aureus strains isolated from fish processing factory workers

    OpenAIRE

    1988-01-01

    One hundred and twenty two strains of Staphylococcus aureus isolated from throats and palms of 39 workers from 6 fish processing factories situated in and around Cochin were tested for their sensitivity to nine commonly used antibiotics-ampicillin, chloramphenicol, erythromycin, kanamycin, neomycin, penicillin, polymyxin-B, streptomycin and tetracycline. Highest percentage of resistance was observed towards ampicillin followed by penicillin i.e. 64.75% and 59.84%. Resistance towards other ant...

  11. The resistance of Salmonella spp. isolates from Alabio duck against several antibiotics

    OpenAIRE

    1998-01-01

    A total of 172 isolates of Salmonella spp. consisted of S. typhimurium (70), S. Radar (52), S. senftenberg (25), S. Virchow (14), and S. amsterdam (11) from Alabio duck hatcheries in the District of Hulu Sungai Utara, South Kalimantan, were examined their resistencies against seven kinds of antibiotics, consisted of chloramphenicol, neomycin, trimethoprim, streptomycin, tetracycline, ampicillin, and polymixin B, by using agar disc diffusion method. The results showed that 70 isolates of S. ty...

  12. Anti-biogram and resistogram profiling of Aeromonas species isolated from Malaysian aquatic sources

    OpenAIRE

    Olumide Adedokun Odeyemi; Asmat Ahmad

    2013-01-01

    Objective: To investigate antibiotics and heavy metals resistance profile of Aeromonas species isolated from Kuala Gula and Kuala Sepetang, Perak. Methods: Isolated Aeromonas species were subjected to 12 antibiotics: penicillin G 10 units, tetracycline 30 µg, novobiocin 5 µg, nitrofurantoin 100 µg, ampicillin 10 µg, chloramphenicol 10 µg, fluconazole 25 µg, gentamicin 10 µg, streptomycin 10 µg and 25 µg, kanamycin 30 µg, and vancomycin 30 µg and 5 heavy metals: MnSO4.H2O, Cr(NO...

  13. Isolamento, armazenamento e determinação da colonização por fungos “dark septate” a partir de plantas de arroz. = Isolation, storage and determination of fungal colonization “dark septate” from rice plants.

    OpenAIRE

    Karen Gonçalves Ribeiro; Gilmara Maria Duarte Pereira; Cátia Aparecida Mosqueira; Alexandre Cardoso Baraúna; Marcos José Salgado Vital; Krisle da Silva; Jerri Édson Zilli

    2011-01-01

    Endophyte fungi known as DSEF can be plant-growth-promoting. Aiming to improve a methodology for the isolation, storage and determine the rice roots colonization by “dark septate”, a study was developed based on the achievement of these microorganisms in Oryza glumaepatula plants collected in Amazon region. The plant roots of twelve O. glumaepatula samples were sectioned, disinfected, and placed in plates with agar-malte medium added of chloramphenicol, sulphametazole and trimetropin. The iso...

  14. Infection of the ferret stomach by isogenic flagellar mutant strains of Helicobacter mustelae.

    OpenAIRE

    Andrutis, K A; Fox, J G; Schauer, D B; Marini, R P; Li, X.; L. Yan; Josenhans, C; Suerbaum, S

    1997-01-01

    Helicobacter mustelae, like Helicobacter pylori, possesses two flagellin proteins, FlaA and FlaB. Isogenic mutant strains of H. mustelae have been constructed by disruption of the flaA or flaB gene with a kanamycin resistance cassette or by introduction of both a kanamycin and a chloramphenicol resistance gene to produce a double mutant. To determine whether one or both flagellin proteins are necessary for colonization and persistence of infection with H. mustelae, 19 ferrets, specific pathog...

  15. Salmonella enterica Typhimurium fljBA operon stability: implications regarding the origin of Salmonella enterica I 4,[5],12:i:.

    Science.gov (United States)

    Tomiyama, M P O; Werle, C H; Milanez, G P; Nóbrega, D B; Pereira, J P; Calarga, A P; Flores, F; Brocchi, M

    2015-12-29

    Salmonella enterica subsp enterica serovar 4,5,12:i:- has been responsible for many recent Salmonella outbreaks worldwide. Several studies indicate that this serovar originated from S. enterica subsp enterica serovar Typhimurium, by the loss of the flagellar phase II gene (fljB) and adjacent sequences. However, at least two different clones of S. enterica 4,5,12:i:- exist that differs in the molecular events responsible for fljB deletion. The aim of this study was to test the stability of the fljBA operon responsible for the flagellar phase variation under different growth conditions in order to verify if its deletion is a frequent event that could explain the origin and dissemination of this serovar. In fact, coding sequences for transposons are present near this operon and in some strains, such as S. enterica Typhimurium LT2, the Fels-2 prophage gene is inserted near this operon. The presence of mobile DNA could confer instability to this region. In order to examine this, the cat (chloramphenicol acetyltransferase) gene was inserted adjacent to the fljBA operon so that deletions involving this genomic region could be identified. After growing S. enterica chloramphenicol-resistant strains under different conditions, more than 104 colonies were tested for the loss of chloramphenicol resistance. However, none of the colonies were sensitive to chloramphenicol. These data suggest that the origin of S. enterica serovar 4,5,12:i:- from Typhimurium by fljBA deletion is not a frequent event. The origin and dissemination of 4,5,12:i:- raise several questions about the role of flagellar phase variation in virulence.

  16. Inducible repair system in Haemophilus influenzae unaccompanied by mutation.

    OpenAIRE

    Notani, N. K.; Setlow, J K

    1980-01-01

    Weigle reactivation of ultraviolet-irradiated HPlc1 phage was observed after ultraviolet or mitomycin C treatment of Haemophilus influenzae cells. The amount of reactivation was considerably increased when the treated cells were incubated in growth medium before infection. The presence of chloramphenicol during this incubation abolished the reactivation. No mutation of this phage accompanied the reactivation. When cells were treated so as to produce a maximal reactivation of phage, neither re...

  17. Glutathione S-transferase Ya subunit gene: identification of regulatory elements required for basal level and inducible expression.

    OpenAIRE

    Telakowski-Hopkins, C A; King, R. G.; Pickett, C B

    1988-01-01

    The function of the 5'-flanking region of a rat glutathione S-transferase Ya subunit structural gene has been examined in homologous and heterologous cells. By using the 5'-flanking region of the Ya subunit gene fused to the structural gene encoding chloramphenicol acetyltransferase, we have identified two cis-acting regulatory elements in the upstream region of the Ya gene. One element is required for maximum basal level expression in homologous cells, whereas maximum basal level expression ...

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

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

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

  19. Genome Sequence of a Multidrug-Resistant Strain of Klebsiella pneumoniae, BAMC 07-18, Isolated from a Combat Injury Wound

    Science.gov (United States)

    2014-11-26

    including azithromycin, ceftazidime, chloramphenicol, and tetracycline; however, BAMC 07-18 is sensitive to imipenem, a carbapenem , both in vivo and in...alterations in morphology (7), leading us to question the genetic mechanisms of the pleiotropic effects of imipenem against this carbapenem -sensitive...RNA sequencing analysis (RNA-seq) will allow us to explore the pleiotropic effects of carbapenems on K. pneumoniae biofilms and provide novel

  20. Antimicrobial activity of the leaf extracts of Hyptis suaveolens (L. poit

    Directory of Open Access Journals (Sweden)

    Mandal S

    2007-01-01

    Full Text Available Steam distillation, petroleum ether, and ethanol extracts from Hyptis suaveolens leaves were evaluated for their antimicrobial activity in vitro . Steam distillation extract exhibited broad-spectrum antibacterial and antifungal activity against the tested organisms. It showed highest antifungal and antibacterial activity against Aspergillus niger and Micrococcus luteus, respectively. Activity indices of A. niger against miconazole (25 µg/ml and M. luteus against chloramphenicol (10 µg/ml were 0.89 and 0.67, respectively.

  1. Molecular Analysis of and Identification of Antibiotic Resistance Genes in Clinical Isolates of Salmonella typhi from India

    OpenAIRE

    Shanahan, Philippa M. A.; Jesudason, Mary V.; Thomson, Christopher J.; Amyes, Sebastian G. B.

    1998-01-01

    A representative sample of 21 Salmonella typhi strains isolated from cultures of blood from patients at the Christian Medical College and Hospital, Vellore, India, were tested for their susceptibilities to various antimicrobial agents. Eleven of the S. typhi strains possessed resistance to chloramphenicol (256 mg/liter), trimethoprim (64 mg/liter), and amoxicillin (>128 mg/liter), while four of the isolates were resistant to each of these agents except for amoxicillin. Six of the isolates wer...

  2. Gene Disruption by Homologous Recombination in the Xylella fastidiosa Citrus Variegated Chlorosis Strain

    Science.gov (United States)

    Gaurivaud, Patrice; Souza, Leonardo C. A.; Virgílio, Andrea C. D.; Mariano, Anelise G.; Palma, Renê R.; Monteiro, Patrícia B.

    2002-01-01

    Mutagenesis by homologous recombination was evaluated in Xylella fastidiosa by using the bga gene, coding for β-galactosidase, as a model. Integration of replicative plasmids by homologous recombination between the cloned truncated copy of bga and the endogenous gene was produced by one or two crossover events leading to β-galactosidase mutants. A promoterless chloramphenicol acetyltransferase gene was used to monitor the expression of the target gene and to select a cvaB mutant. PMID:12200328

  3. Ocular injury secondary to sheep bile exposure

    Science.gov (United States)

    Okullo, Alfin Taddeo; Low, Tim; Baker, Louise Leslie

    2012-01-01

    A 57-year-old abattoir worker was seen at a general practitioner after sheep bile splashed into his left eye. Flourescein examination revealed extensive ulceration involving at least two-thirds of the corneal surface. Copious irrigation with normal saline, application of chloramphenicol ointment and an eye patch resulted in excellent healing within 2 days with return to normal vision for the patient thereafter. PMID:23208813

  4. Antimicrobial susceptibility of Escherichia coli isolated from shrimp (Litopenaeus vannamei) and pond environment in northeastern Brazil.

    Science.gov (United States)

    Vieira, Regine H S Dos F; Carvalho, Edirsana M R; Carvalho, Fatima C T; Silva, Camila M; Sousa, Oscarina V; Rodrigues, Dalia P

    2010-04-01

    This study aimed to test the susceptibility of Escherichia coli strains isolated from the water, bottom sediments and individuals cultivated in shrimp farm ponds, to antibiotics belonging to different families, namely B-Lactams: Imipenem (IPM; 10 micro g), Ampicillin (AMP; 10 micro g), Cephalothin (CEP; 30 micro g), Cefoxitin (FOX; 30 micro g), Ceftriaxone (CRO; 30 micro g); Tetracycline: Tetracycline (TCY; 30 micro g); Aminoglycosides: Gentamicin (GEN; 10 micro g), Amikacin (AMK; 30 micro g); Chloramphenicol: Chloramphenicol (CHO; 30 micro g); Fluoroquinolones: Ciprofloxacin (CIP; 5 micro g); Nitrofurans: Nitrofurantoin (NIT; 300 micro g); Sulfonamides: Trimethoprim-Sulfamethoxazole (SXT; 30 micro g); Quilononas: Nalidixic Acid (NAL; 30 micro g). In the laboratory, the method of dissemination (Test Kirby-Bauer) was performed in order to fulfill the antibiogram tests. The results showed high indices of resistance to Imipenem, Cephalothin and Ampicillin. Chloramphenicol, Nitrofurantoin, Cefoxitin, Ceftiaxone and Ciprofloxacin have displayed the highest index of sensitive strains. The antibiotic resistance index (ARI) and the multiple resistance index (MAR) varied within the ranges of 0.068-0.077 and 0.15-0.39, respectively. More than 90.5% of strains of Escherichia coli showed a variety of resistance profiles to the tested antibiotics. The high indices of resistance may be a consequence of indiscriminate use of antibiotics, but also the transfer of resistance through mobile genetic elements found in shrimp farms.

  5. Comparison of antimicrobial resistance in Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes strains isolated from organic and conventional poultry meat.

    Science.gov (United States)

    Miranda, J M; Vázquez, B I; Fente, C A; Calo-Mata, P; Cepeda, A; Franco, C M

    2008-12-01

    The presence of Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes was determined in 55 samples of organic poultry meat and in 61 samples of conventional poultry meat. A total of 220 E. coli, 192 S. aureus, and 71 L. monocytogenes strains were analyzed by an agar disk diffusion assay for their resistance to ampicillin, cephalothin, chloramphenicol, ciprofloxacin, doxycycline, fosfomycin, gentamicin, nitrofurantoin, streptomycin, and sulfisoxazole (E. coli); chloramphenicol, ciprofloxacin, clindamycin, doxycycline, erythromycin, gentamicin, nitrofurantoin, oxacillin, and sulfisoxazole (S. aureus); and chloramphenicol, doxycycline, erythromycin, gentamicin, sulfisoxazole, and vancomycin (L. monocytogenes). The results indicated a significantly higher (P poultry meat as compared with conventional poultry meat. E. coli isolated from organic poultry meat exhibited lower levels of antimicrobial resistance against 7 of the 10 antimicrobials tested as compared with isolates recovered from conventional meat. In the case of S. aureus and L. monocytogenes isolated from conventional poultry, antimicrobial resistance was significantly higher only for doxycycline as compared with strains isolated from organic poultry. In the case of E. coli, the presence of multiresistant strains was significantly higher (P poultry meat as compared with organic poultry meat. Organically farmed poultry samples showed significantly lower development of antimicrobial resistance in intestinal bacteria such as E. coli.

  6. Antimicrobial resistance among invasive Haemophilus influenzae strains: results of a Brazilian study carried out from 1996 through 2000

    Directory of Open Access Journals (Sweden)

    Casagrande S.T.

    2002-01-01

    Full Text Available A total of 1712 strains of Haemophilus influenzae isolated from patients with invasive diseases were obtained from ten Brazilian states from 1996 to 2000. ß-Lactamase production was assessed and the minimum inhibitory concentrations (MIC of ampicillin, chloramphenicol, ceftriaxone and rifampin were determined using a method for broth microdilution of Haemophilus test medium. The prevalence of strains producing ß-lactamase ranged from 6.6 to 57.7%, with an overall prevalence of 18.4%. High frequency of ß-lactamase-mediated ampicillin resistance was observed in Distrito Federal (25%, São Paulo (21.7% and Paraná (18.5%. Of the 1712 strains analyzed, none was ß-lactamase negative, ampicillin resistant. A total of 16.8% of the strains were resistant to chloramphenicol, and 13.8% of these also presented resistance to ampicillin, and only 3.0% were resistant to chloramphenicol alone. All strains were susceptible to ceftriaxone and rifampin and the MIC90 were 0.015 µg/ml and 0.25 µg/ml, respectively. Ceftriaxone is the drug of choice for empirical treatment of bacterial meningitis in pediatric patients who have not been screened for drug susceptibility. The emergence of drug resistance is a serious challenge for the management of invasive H. influenzae disease, which emphasizes the fundamental role of laboratory-based surveillance for antimicrobial resistance.

  7. Prevalence, antibiotic resistance and RAPD typing of Campylobacter species isolated from ducks, their rearing and processing environments in Penang, Malaysia.

    Science.gov (United States)

    Adzitey, Frederick; Rusul, Gulam; Huda, Nurul; Cogan, Tristan; Corry, Janet

    2012-03-15

    We report for the first time on the prevalence, antibiotic resistance and RAPD types of Campylobacter species in ducks and duck related environmental samples in Malaysia. Samples were examined by enrichment in Bolton Broth followed by plating onto modified Charcoal Cefoperazone Deoxycholate agar (mCCDA) and/or plating directly onto mCCDA. A total of 643 samples were screened, and the prevalence of Campylobacter spp. in samples from different sources ranged from 0% to 85%. The method of isolation had a significant (P<0.05) effect on the isolation rate. One hundred and sixteen Campylobacter isolates, comprising of 94 Campylobacter jejuni, 19 Campylobacter coli and three Campylobacter lari, were examined for their sensitivity to 13 antibiotics. Majority of the C. jejuni isolates were resistant to cephalothin (99%), tetracycline (96%), suphamethoxazole/trimethoprim (96%), and very few were resistant to gentamicin (5%), chloramphenicol (7%) and erythromycin (1%). All C. coli isolates were resistant to cephalothin, nalidixic acid, norfloxacin and tetracycline but susceptible to chloramphenicol, erythromycin and gentamicin. The three C. lari isolates were resistant to all the antibiotics tested except chloramphenicol and gentamicin (1/3 and 2/3 susceptible, respectively). Genetic diversity of Campylobacter isolates were determined using random amplification of polymorphic DNA (RAPD). C. jejuni and C. coli isolates belong to fifty-eight and twelve RAPD types, respectively.

  8. [Therapeutic aspects of salmonellosis in veal calves].

    Science.gov (United States)

    Groothuis, D G; van Miert, A S

    1985-01-01

    The present investigation was undertaken to improve dosage regimens--using amoxycillin, chloramphenicol or trimethoprim/sulphadiazin--in Salmonella dublin or Salmonella typhimurium infected vealcalves. The pharmacokinetic of these drugs was studied after i/v, oral, and i/m administration (bio-availability, local irritation at the injection site, volume of distribution, and elimination half-life). The most important conclusion was that amoxycillin, chloramphenicol, and trimethoprim were suitable for oral administration to vealcalves, although the bioavailability of chloramphenicol and trimethoprim was significantly less when administered with a milk replacer concurrently. In vitro the antibacterial activities of these drugs were compared with each other. Addition of sulphadiazin to trimethoprim lowered its MIC for S. dublin, but it reduced the killing rate compared to that of trimethoprim alone. In the efficacy studies the activities of several serum enzymes and the plasma concentrations of Fe, Zn, Cu, and bilirubine were measured. Using optimal dose regimens based on MIC values and blood levels treatment with either of the three drugs was of equal efficacy.

  9. Study of endotoxin release by Salmonella thyphi by antibiotics in Chromogenic Limulus Amebocyte Lyssate Method

    Directory of Open Access Journals (Sweden)

    Shagari G

    1997-07-01

    Full Text Available It seems, rapid destruction of gram negative bacteria by antibiotics contribute to the clinical deterioration of some patients with lethal endotoxemia. In this research we evaluated LPS (lipopolysaccharide release during antibiotic killing of salmonella typhi (Ty2-5536. The organism was incubated in the presence of Chloramphenicol, Ampicillin and Co-trimoxazole at concentrations that killed >99.9% of the organisms as determined by quantitative culture techniques. After incubation the antibiotic-bacterial cultures were centrifuged and the supernatants were filtered and collected for "in vivo" and "in vitro" studies. Injection of 1 ml/kg of filtrates in rabbits raised normal temperature of the animals by 1.2°C that it showes the presence of LPS in the filtrates. Quantitative chromogenic limulus amebocyte lyssate (L.A.L assay was used to determine the amount of LPS in the filtrates. The amount of LPS was 86.67±2.53 Pg/ml for chloramphenicol, 113.33±8.07 Pg/ml for Ampicillin and 134.18±11.59 Pg/ml for Co-trimoxazole. According to our investigation chloramphenicol is the best antibiotic against S.typhi because it decrease the induced-pathological effects of LPS in gram negative infection

  10. Integron presence in a multiresistant Morganella morganii isolate.

    Science.gov (United States)

    Rojas, Laura; Vinuesa, Teresa; Tubau, Fe; Truchero, Consol; Benz, Roland; Viñas, Miguel

    2006-06-01

    A multiresistant strain of Morganella morganii was isolated from a patient affected by several severe pathologies. The isolate was found to be resistant to the following antimicrobials: ampicillin, nalidixic acid, cefalothin, cefoxitin, ceftriaxone, ciprofloxacin, chloramphenicol, streptomycin, erythromycin, gentamicin, novobiocin, penicillin, rifampicin, tetracycline and violet crystal. Mechanisms leading to this multiresistance were studied. Porins of M. morganii multiresistant and wild-type strains were analysed by sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and were characterised by their ability to form channels in planar black lipid bilayers. The channels formed by porins from multiresistant and susceptible strains suggested that the porins of the multiresistant strain were not responsible for resistance. A 6.6 kb plasmid (pML2003) was detected, isolated and studied. pML2003 included two integrons. Direct sequencing revealed that one of the integrons contained two cassettes, aminoglycoside adenyltransferase (aadB) and chloramphenicol acetyltransferase (catB3) conferring resistance to aminoglycosides and chloramphenicol, respectively. The second integron contained carbenicillinase (blaP1b) and adenyltransferase (aadA2), which confer resistance to beta-lactamases and streptomycin, respectively.

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

    Science.gov (United States)

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

    2002-03-01

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

  12. 印第安纳沙门氏菌对氯霉素类药物耐药性分析%Resistance analysis of Salmonella Indiana to the chlmphenicols

    Institute of Scientific and Technical Information of China (English)

    陆彦; 晏志勋; 赵红玉; 侯晓林; 吴国娟

    2013-01-01

    [Objective] To investigate the characteristics of chloramphenicols resistance and the prevalence of resistance genes in Salmonella Indiana from chicken.[Methods] The samples were isolated from chicken hatcheries,farms and slaughterhouses in Shandong Province.The isolates were identificated and tested the drug susceptibility,designing primers for the resistance genes of chloramphenicols in strains were detected by PCR and sequence analysis.[Results] The results showed that the isolation rate of Salmonella Indiana was 23.28%.The resistance rates of Salmonella Indiana from hatcheries,farms,slaughterhouses to chloramphenicol were 50%,83.33%,93.30%,florfenicol were 83.33%,100%,100%,thiamphenicol were 63%,65%,77% respectively.In 80 chloramphenicols resistant strains,54 strains had detected catA1 gene,74 strains had detectedfloR gene,and the 5 strains had detected cmlA gene.[Conclusion] These results indicated that the resistance rates of Salmonella Indiana to chloramphenicols were different from hatcheries,farms and slaughterhouses.The catA1 gene and floR gene were widely existed in chloramphenicols resistant strains.%[目的]调查鸡源沙门氏菌对氯霉素类药物的耐药特征和相关耐药基因的流行情况.[方法]从山东省部分地区鸡孵化场、养殖场、屠宰场分离样品进行沙门氏菌鉴定和药物敏感性试验;设计引物,对氯霉素类药物的耐药基因进行PCR扩增和序列分析.[结果]试验分离到印第安纳沙门氏菌,分离率为23.28%.孵化场、养殖场、屠宰场印第安纳沙门氏菌对氯霉素耐药率分别为50.00%、83.33%和93.30%,对氟苯尼考耐药率为83.33%、100%和100%,对甲砜霉素耐药率为63%、65%和77%.在80株氯霉素类耐药菌株中,54株检测到catA1基因,74株检测到floR基因,5株检测到cmlA基因.[结论]不同来源印第安纳沙门氏菌对氯霉素类药物耐药率存在差异,catA1和floR基因广泛存在于耐药菌株中.

  13. Antibacterial activity of fourGracilaria species of red seaweeds collected from Mandapam Coast, Gulf of Mannar Marine Biosphere Reserve, India

    Institute of Scientific and Technical Information of China (English)

    Sethu Rameshkumar; Kolidoss Radhakrishnan; Arasan Sreenivasan; Samraj Aanand

    2016-01-01

    Objective:To study the antibacterial activities of diethyl ether, toluene, ethanol and methanol extracts of red seaweeds such asGracilaria crassa(G. crassa),Gracilaria folifera(G. folifera), Gracilaria debilis (G. debilis) andGracilaria corticata. Methods:The crude extracts were tested against different types of Gram-positive and -negative bacterial strains and all the seaweed extracts were tested a broad spectrum of antibacterial activity. Antibacterial activity was made using paper disc diffusion method. Four organic solvents (diethyl ether, toluene, methanol and ethanol) were used separately in a Soxhlet apparatus for seven bacterial strains. Antibacterial activity of the known antibiotics such as chloramphenicol, streptomycin, kanamycin and ampicillin was determined by testing them against different test organisms. Results:The high antibacterial activity was noted in the extracts ofG. crassa,G. folifera andG. debilis. However,G. crassa andG. debilis have good antibacterial activity. Pathogens likeBacillus subtilis andEscherichia coli were less susceptible to the methanol and diethyl ether extracts ofG. folifera. The comparative study on the antibacterial activity was also made by using 200μg concentration of solvent extracts (diethyl ether, ethanol, toluene and methanol)and different five antibiotics such as chloramphenicol, streptomycin, kanamycin, amoxicillin and ampicillin. The bacterial strains tested were more sensitive to chloramphenicol, streptomycin, kanamycin, and ampicillin when compared to algal extracts. Conclusions: The present study proved that the extracts ofG. crassa,G. folifera andG. debilis have high antibacterial activity. AlthoughG. crassa andG. debilis showed good antibacterial activity, many known antibiotics are active against a few organisms individually. Hence, the extracts of seaweeds were active against all test organisms used and the activities were comparable to that of antibiotics and the seaweeds offer a feasible alternative for

  14. Antibacterial activity of four Gracilaria species of red seaweeds collected from Mandapam Coast, Gulf of Mannar Marine Biosphere Reserve, India

    Directory of Open Access Journals (Sweden)

    Sethu Rameshkumar

    2016-09-01

    Full Text Available Objective: To study the antibacterial activities of diethyl ether, toluene, ethanol and methanol extracts of red seaweeds such as Gracilaria crassa (G. crassa, Gracilaria folifera (G. folifera, Gracilaria debilis (G. debilis and Gracilaria corticata. Methods: The crude extracts were tested against different types of Gram-positive and -negative bacterial strains and all the seaweed extracts were tested a broad spectrum of antibacterial activity. Antibacterial activity was made using paper disc diffusion method. Four organic solvents (diethyl ether, toluene, methanol and ethanol were used separately in a Soxhlet apparatus for seven bacterial strains. Antibacterial activity of the known antibiotics such as chloramphenicol, streptomycin, kanamycin and ampicillin was determined by testing them against different test organisms. Results: The high antibacterial activity was noted in the extracts of G. crassa, G. folifera and G. debilis. However, G. crassa and G. debilis have good antibacterial activity. Pathogens like Bacillus subtilis and Escherichia coli were less susceptible to the methanol and diethyl ether extracts of G. folifera. The comparative study on the antibacterial activity was also made by using 200 μg concentration of solvent extracts (diethyl ether, ethanol, toluene and methanoland different five antibiotics such as chloramphenicol, streptomycin, kanamycin, amoxicillin and ampicillin. The bacterial strains tested were more sensitive to chloramphenicol, streptomycin, kanamycin, and ampicillin when compared to algal extracts. Conclusions: The present study proved that the extracts of G. crassa, G. folifera and G. debilis have high antibacterial activity. Although G. crassa and G. debilis showed good antibacterial activity, many known antibiotics are active against a few organisms individually. Hence, the extracts of seaweeds were active against all test organisms used and the activities were comparable to that of antibiotics and the

  15. Development of UDP-glucuronosyltransferase activity toward digitoxigenin-monodigitoxoside in neonatal rats.

    Science.gov (United States)

    Watkins, J B; Klaassen, C D

    1985-01-01

    Glucuronidation is low or undetectable in embryonic and early fetal tissues and changes to adult levels at rates depending on the acceptor, tissue, and species. Because other data indicate there may be a specific UDP-glucuronosyltransferase (GT) in the liver of adult rats that glucuronidates digitoxigenin-monodigitoxoside (DIG), the development of GT activity in neonatal rats toward DIG was compared with that of other acceptors. Conjugation of p-nitrophenol and 1-naphthol was higher at birth and decreased to adult levels by 20 days of age. Glucuronidation of chloramphenicol, morphine, valproic acid, and bilirubin increased from birth to adult activity by 20 days of age. Conjugation of phenolphthalein, estrone, and diethylstilbestrol was low in 1-day-old rats and higher than adult in 20-day-old animals. In contrast, glucuronidation of DIG was barely detectable (9% of adult) in 20-day-old rats. The concentration of UDP-glucuronic acid was 50% of adult levels at birth and increased to adult values by 10 days of age. Administration of 3-methylcholanthrene on days 6 to 9 after birth significantly stimulated GT activity toward 1-naphthol, p-nitrophenol, and morphine, whereas phenobarbital precociously increased conjugation of chloramphenicol, valproic acid, morphine, and diethylstilbestrol. Pregnenolone-16 alpha-carbonitrile enhanced the development of GT activity toward morphine, chloramphenicol, valproic acid, bilirubin, diethylstilbestrol, and estrone. Glucuronidation of DIG was not increased after 3-methylcholanthrene or phenobarbital, but could be induced after pregnenolone-16 alpha-carbonitrile to 7% of adult values in 10-day-old rats.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Microbiological bioassay using Bacillus pumilus to detect tetracycline in milk.

    Science.gov (United States)

    Tumini, Melisa; Nagel, Orlando Guillermo; Althaus, Rafael Lisandro

    2015-05-01

    The tetracyclines (TCs) are widely used in the treatment of several diseases of cattle and their residues may be present in milk. To control these residues it is necessary to have available inexpensive screening methods, user-friendly and capable of analysing a high number of samples. The purpose of this study was to design a bioassay of microbiological inhibition in microtiter plates with spores of Bacillus pumilus to detect TCs at concentrations corresponding to the Maximum Residue Limits (MRLs). Several complementary experiments were performed to design the bioassay. In the first study, we determined the concentration of spores that produce a change in the bioassay's relative absorbance in a short time period. Subsequently, we assessed the concentration of chloramphenicol required to decrease the detection limit (DL) of TCs at MRLs levels. Thereafter, specificity, DL and cross-specificity of the bioassay were estimated. The most appropriate microbiological inhibition assay had a B. pumilus concentration of 1.6 × 10(9) spores/ml, fortified with 2500 μg chloramphenicol/l (CAP) in Mueller Hinton culture medium using brilliant black and toluidine blue as redox indicator. This bioassay detected 117 μg chlortetracycline/l, 142 μg oxytetracycline/l and 105 μg tetracycline/l by means of a change in the indicator's colour in a period of 5 h. The method showed good specificity (97.9%) which decreased slightly (93.3%) in milk samples with high somatic cell counts (>250,000 cells/ml). Furthermore, other antimicrobials studied (except neomycin) must be present in milk at high concentrations (from >5 to >100 MRLs) to produce positive results in this assay, indicating a low cross specificity.

  17. Antimicrobial resistance of Salmonella spp. isolated from food

    Science.gov (United States)

    Mąka, Łukasz; Popowska, Magdalena

    This review summarizes current data on resistance among Salmonella spp. isolates of food origin from countries in different regions of the world. The mechanisms of resistance to different groups of antimicrobial compounds are also considered. Among strains resistant to quinolones and/or fluoroquinolones the most prevalent mechanism is amino acid substitutions in quinolone resistance-determining region (QRDR) of genes gyrA, parC but mechanism of growing importance is plasmid-mediated quinolone resistance (PMQR) associated with genes qnrA, qnrB, qnrC, qnrD, qnrS but frequency of their detection is different. Resistance to sulfonamides is mostly associated with genes sul1 and sul2, while resistance to trimethoprim is associated with various variants of dhfr ( dfr) genes. Taking into account Salmonella spp. strains isolated from food, resistance to β-lactams is commonly associated with β-lactamases encoding by blaTEM genes. However strains ESBL and AmpC – positive are also detected. Resistance to aminoglicosides is commonly result of enzymatic inactivation. Three types of aminoglycoside modifying enzyme are: acetyltransferases (AAC), adenyltransferases (ANT) and phosphotransferases (APH). Resistance to tetracyclines among Salmonella spp. isolated from food is most commonly associated with active efflux. Among numerous genetic determinants encoding efflux pumps tetA, tetB, tetC, tetD, tetE and tetG are reported predominatingly. One of the most common mechanisms of resistance against chloramphenicol is its inactivation by chloramphenicol acetyltrasferases (CATs), but resistance to this compound can be also mediated by chloramphenicol efflux pumps encoded by the genes cmlA and floR. It is important to monitor resistance of Salmonella isolated from food, because the globalization of trade, leading to the long-distance

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

    Directory of Open Access Journals (Sweden)

    Muhammad A. Akond

    2009-01-01

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

  19. Waterborne typhoid fever in Dade County, Florida. Clinical and therapeutic evaluation of 105 bacteremic patients.

    Science.gov (United States)

    Hoffman, T A; Ruiz, C J; Counts, G W; Sachs, J M; Nitzkin, J L

    1975-10-01

    An extensive outbreak of waterborne typhoid fever occurred in 1973 at a migrant labor camp in Dade County, Florida. Blood cultures from 105 of the 188 patients with proved or presumptive cases of typhoid fever grew Salmonella typhi. The clinical and laboratory findings in these patients were reviewed. Fever, usually with temperatures above 38.8 degrees C and of the sustained type, was a primary manifestation of disease, although a majority of the patients also complained of headache and gastroenteric symptoms. Hepatic or splenic enlargement was present in 52 per cent and 42 per cent, respectively, whereas rose spots were detected in only 13 per cent. The total leukocyte count was normal in 74 per cent, but serum levels of liver and muscle enzymes were frequently elevated. Gastrointestinal, pulmonary and neurologic complications were infrequent; circulatory failure was not observed. Defervescence in response to antibiotic therapy was variable; however, the median response among 68 patients who received chloramphenicol was two days less than that in 34 patients treated with ampicillin. There was one possible treatment failure with ampicillin. The relapse rate of 10 per cent in chloramphenicol-treated patients was not significantly greater than the 3 per cent rate among those treated with ampicillin. Serologic studies for typhoid fever were of limited diagnostic value since the titer of agglutinins was 1:160 or higher in 49 per cent of the serums obtained before treatment, and a fourfold rise in titer occurred in only 24 per cent of 57 patients studied. The serologic response to chloramphenicol treatment did not differ from that to ampicillin.

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

    Directory of Open Access Journals (Sweden)

    Ifeoma Chinyere UGWU

    2015-09-01

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

  1. Comportamento, sobrevivência e desenvolvimento de lebistes, Poecilia reticulata, submetidos a agentes utilizados na profilaxia de doenças - DOI: 10.4025/actascianimsci.v27i4.1183 Behaviour, survival, and development of guppies, Poecilia reticulata, submitted to agents used in the prophylaxis of diseases - DOI: 10.4025/actascianimsci.v27i4.1183

    Directory of Open Access Journals (Sweden)

    Wilson Rogério Boscolo

    2005-03-01

    Full Text Available Com o objetivo de avaliar o comportamento, a sobrevivência e desenvolvimento de larvas saudáveis de Poecilia reticulata submetidas à profilaxia contra bactérias, fungos e parasitas, foi conduzido no Laboratório de Aqüicultura da Universidade Estadual de Maringá, Estado do Paraná, um experimento delineado ao acaso com 6 tratamentos (controle, azul de metileno, cloranfenicol, formalina, KMnO4 e NaCl e 4 repetições. Os banhos profiláticos variaram conforme o tratamento, de 30 minutos a 48 horas. Posteriormente, avaliou-se, por 20 dias, o desenvolvimento dos animais. A análise comportamental realizada durante o banho mostrou que, quando expostos à formalina, os animais perdiam o senso de direção e chocavam-se contra a parede. O desenvolvimento das larvas no tratamento com cloranfenicol apresentou-se melhor (P Aiming to evaluate the behavioural, survival and developmental responses of healthy larvae of Poecilia reticulata subjected to the prophyllatic against bacteria, fungi and parasites, a randomized experiment was carried out at the Aquaculture Laboratory of the State University of Maringá, state of Paraná, using six treatments (control, methylene blue, chloramphenicol, formalin, KMnO4 and NaCl and four repetitions. Length prophylactic treatment varied from 30 minutes to 48 hours. After bath treatment, animals’ growth was evaluated during the following 20 days. Behavioural analysis during bath treatment showed that when the animals were exposed to formalin, they lost their sense of direction and collided against the wall. In the treatment with chloramphenicol, development of the larvae was better (P < 0.05 when treated with formalin. In relation to survival, there were no differences between the treatments. Thus, any methodology may be applied in this study when related to survival. Prophylaxis with chloramphenicol is the preferred treatment to formalin when evaluating growth

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

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-02-01

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

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

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-12-01

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

  4. [Sensitivity of Kingella kingae to antibiotics].

    Science.gov (United States)

    Prère, M F; Seguy, M; Vezard, Y; Lareng, M B

    1986-06-01

    Kingella kingae is a small Gram negative rod of the Neisseriaceae family, formerly called Moraxella kingae. This microorganism is found occasionally in the oral cavity and is capable of causing infections. We report three cases of septic arthritis in children due to K. kingae. In vitro susceptibility of the recovered strains was tested using determination of MICs in agar. The strains were susceptible to penicillin, ampicillin, ticarcillin, cephalothin, cefotaxime, gentamicin, chloramphenicol, tetracycline, trimethoprim-sulfamethoxazole, and pefloxacin, less susceptible to erythromycin and resistant to lincomycin (MIC 32 mg/l).

  5. Stored-product insects carry antibiotic-resistant and potentially virulent enterococci.

    Science.gov (United States)

    Channaiah, Lakshmikantha H; Subramanyam, Bhadriraju; McKinney, Leland J; Zurek, Ludek

    2010-11-01

    A total of 154 enterococcal isolates from 95 stored-product insects collected from a feed mill, a grain storage silo, and a retail store were isolated and identified to the species level using PCR. Enterococcus casseliflavus represented 51% of the total isolates, followed by Enterococcus gallinarum (24%), Enterococcus faecium (14%), Enterococcus faecalis (7%), and Enterococcus hirae (5%). Many isolates were resistant to tetracycline (48%), followed by streptomycin (21%), erythromycin (14%), kanamycin (13%), ciprofloxacin (12%), ampicillin (4%), and chloramphenicol (resistance gene, tetM, was transferable among E. faecalis by conjugation. These data demonstrated that stored-product insects can serve as potential vectors in disseminating antibiotic-resistant and potentially virulent enterococci.

  6. Caavuranamide, a novel steroidal alkaloid from the ripe fruits of Solanum caavurana Vell. (Solanaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Vaz, Nelissa Pacheco; Santos, Erica L.; Marques, Francisco A.; Maia, Beatriz H.L.N. Sales, E-mail: noronha@ufpr.br [Departamento de Quimica, Universidade Federal do Parana, Centro Politecnico, Curitiba, PR (Brazil); Costa, Emmanoel V. [Departamento de Quimica, Universidade Federal de Sergipe, Sao Cristovao, SE (Brazil); Mikich, Sandra Bos [Laboratorio de Ecologia, Embrapa Florestas, Colombo, PR (Brazil); Braga, Raquel M. [Instituto de Quimica, Universidade Estadual de Campinas, SP (Brazil); Delarmelina, Camila; Duarte, Marta C.T. [Divisao de Microbiologia, Centro Pluridisciplinar de Pesquisas Quimicas Biologicas e Agricolas (CPQBA), Universidade Estadual de Campinas, SP (Brazil); Duarte, Marta C.T.; Ruiz, Ana Lucia T.G.; Souza, Vanessa H.S.; Carvalho, Joao E. de [Divisa de Farmacologia e Toxicologia, Centro Pluridisciplinar de Pesquisas Quimicas Biologicas e Agricolas (CPQBA), Universidade Estadual de Campinas, SP (Brazil)

    2012-07-01

    Phytochemical investigation of the ripe fruits of Solanum caavurana Vell. (Solanaceae) afforded a novel steroidal alkaloid with spirosolane-type skeleton, named as caavuranamide, together with the alkaloids 4-tomatiden-3-one and 5{alpha}-tomatidan-3-one. Their structures were elucidated on the basis of spectroscopic methods. The antiproliferative and antimicrobial activities for the ethanolic extract, sub-fractions obtained from partition and acid-base treatment were also evaluated. Caavuranamide showed antibacterial activity similar to the chloramphenicol positive control against Rhodococcus equi. (author)

  7. An outbreak of multidrug-resistant, quinolone-resistant Salmonella enterica serotype typhimurium DT104

    DEFF Research Database (Denmark)

    Molbak, K.; Baggesen, Dorte Lau; Aarestrup, Frank Møller

    1999-01-01

    Background Food-borne salmonella infections have become a major problem in industrialized countries. The strain of Salmonella enterica serotype typhimurium known as definitive phage type 104 (DT104) is usually resistant to five drugs: ampicillin, chloramphenicol, streptomycin, sulfonamides...... findings here. Results Until 1997, DT104 infections made up less than 1 percent of all human salmonella infections. The strain isolated from patients in the first community outbreak of DT104 in Denmark, in 1998, was resistant to nalidixic acid and had reduced susceptibility to fluoroquinolones...

  8. Engineer Novel Anticancer Bioagents

    Science.gov (United States)

    2009-10-01

    agar supplemented with 200 mg/ml Ap and 25 mg/ml chloramphenicol (Cm) at 37C. Vector pBMTL3-FLP2 was subsequently cured from the mutants by steaking ...NADP+) used in assays was purged extensively with bubbling of nitrogen gas. For a complete assay, 5 ml reduced FK228 (100 mM) and 1 ml enzyme solution...replacement Target depH gene with an internal portion replacement by FRT cassette A 85-bp scar is left at the side of deletion FRT cassette excision

  9. UV-induced modifications in the peptidyl transferase loop of 23S rRNA dependent on binding of the streptogramin B antibiotic, pristinamycin IA

    DEFF Research Database (Denmark)

    Porse, B T; Kirillov, S V; Awayez, M J;

    1999-01-01

    the functionally important peptidyl transferase loop of 23S rRNA at positions m2A2503/psi2504 and G2061/A2062. The modification yields are influenced strongly, and differentially, by P-site-bound tRNA and strongly by some of the peptidyl transferase antibiotics tested, with chloramphenicol producing a shift...... the sequence Cm-C-U-C-G-m2A-psi-G2505 are important for pristinamycin IA binding and/or the antibiotic-dependent modification of 23S rRNA....

  10. Isolation and Antimicrobial Testing of Aeromonas spp., Citrobacter spp., Cronobacter spp., Enterobacter spp., Escherichia spp., Klebsiella spp., and Trabulsiella spp. from the Gallbladder of Pigs.

    Science.gov (United States)

    Evangelopoulou, Grammato; Filioussis, Georgios; Kritas, Spyridon; Kantere, Maria; Burriel, Angeliki R

    2015-01-01

    The presence of Gram-negative bacteria species, other than Salmonella spp., in the gallbladder of pigs was examined. Isolated Gram-negative bacteria were assigned to species using the Microgen™ GnA+B-ID Systems. Of the 64 isolated strains 43 were identified as Escherichia coli, seven as Enterobacter spp., three each as Klebsiella spp., Citrobacterfreundii, Aeromonas hydrophila and Cronobacter sakazakii and one each as Escherichiafergusonii and Trabulsiella guamensis. Their antibiograms showed very high resistance to ampicillin, amoxicillin, tetracycline, chloramphenicol and sulfamethoxazole/trimethoprim. It was concluded that the pigs' gallbladder is a reservoir of potentially pathogenic Gram-negative bacteria for pork consumers.

  11. Optimum management of Citrobacter koseri infection.

    Science.gov (United States)

    Deveci, Aydin; Coban, Ahmet Yilmaz

    2014-09-01

    Low virulent Citrobacter koseri can cause life threatening infections. Neonates and other immunocompromised patients are particularly susceptible to infection from C. koseri. Any infection due to C. koseri mandates antimicrobial therapy based on the sensitivity of the pathogen microorganism. Various types of antibiotics, including aminoglycosides carbapenems, cephalosporins, chloramphenicol and quinolones, are used for the treatment of C. koseri infections. The rational choice of antimicrobial therapy for Citrobacter infections is a challenge for clinicians because there is a sustained increase in antibacterial resistance. We reviewed antimicrobial agents used for C. koseri infections in this review.

  12. Occurrence of integrons and antimicrobial resistance genes among Salmonella enterica from Brazil

    DEFF Research Database (Denmark)

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

    2006-01-01

    . The genetic location of class 1 integrons was determined in 25 isolates by hybridization and plasmid transfer experiments. Results: Fifty-five of the isolates were positive for class I integrons. Integron-positive isolates represented 17 different serovars and were mainly from human (n = 28) and animal (n...... resistance was primarily mediated by sul2 and sul3, tetracycline resistance by tet(B) and tet(A), chloramphenicol resistance by catA1, streptomycin resistance by strA and ampicillin resistance by bla(TEM). bla(CTX) and bla(CMY-2) were found in cephalosporin-resistant isolates. Mating and hybridization...

  13. Transferring Gus gene into intact rice cells by low energy ion beam

    Science.gov (United States)

    Zengliang, Yu; Jianbo, Yang; Yuejin, Wu; Beijiu, Cheng; Jianjun, He; Yuping, Huo

    1993-06-01

    A new technique of transferring genes by low energy ion beam has been reported in this paper. The Gus and CAT (chloramphenicol acetyltransferase) genes, as "foreign" genetic materials, were introduced into the suspension cells and ripe embryos or rice by implantation of 20-30 keV Ar + at doses ranging from 1 × 10 15 to 4 × 10 15 ions/cm 2. The activities of CAT and Gus were detected in the cells and embryos after several weeks. The results indicate that the transfer was a success.

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

    Indian Academy of Sciences (India)

    Ratnesh Haturvedi; Adhey Hyam

    2000-03-01

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

  15. 氯霉素类三甲基硅衍生物的质谱特征及其残留监测

    Institute of Scientific and Technical Information of China (English)

    贺利民; 曾振灵; 刘雅红; 陈建新; 黄显会

    2004-01-01

    Mass characteristics of TMS derivative of chloramphenicol, florfenicol,and thiamphenicol were interpreted manually, respectively. Then SIM mode was performed at m/z 225, m/z 242, m/z 244, m/z 361 for CAP, m/z 178, m/z 257, m/z 259, m/z 394 for FF,and m/z 242, m/z 244, m/z 257, m/z 330 for TAP. A sensitive, reproducible gas chromatographic-mass spectrometric method was developed for simultaneous monitoring residues of fenicols in pork and tissues.

  16. Clonal relationship among Vibrio cholerae O1 El Tor strains isolated in Somalia.

    Science.gov (United States)

    Scrascia, Maria; Pugliese, Nicola; Maimone, Francesco; Mohamud, Kadigia A; Grimont, Patrick A D; Materu, Sadiki F; Pazzani, Carlo

    2009-03-01

    One hundred and three Vibrio cholerae O1 strains, selected to represent the cholera outbreaks which occurred in Somalia in 1998-1999, were characterized by random amplified polymorphic DNA patterns, ribotyping, and antimicrobial susceptibility. All strains showed a unique amplified DNA pattern and 2 closely related ribotypes (B5a and B8a), among which B5a was the more frequently identified. Ninety-one strains were resistant to ampicillin, chloramphenicol, spectinomycin, streptomycin, sulfamethoxazole, and trimethoprim, conferred, except for spectinomycin, by a conjugative plasmid IncC. These findings indicated that the group of strains active in Somalia in the late 1990s had a clonal origin.

  17. SUPRESSION OF MICROSOMAL OXIDATION WEAKENS HISTOCHROME’S DIURETIC EFFECT AT RATS

    Directory of Open Access Journals (Sweden)

    O. S. Talalaeva

    2013-01-01

    Full Text Available Histochrome is the medicinal form of echinochrome (2, 3, 5, 6, 8-pentahydroxy-7-ethyl-1,4-naphthoquinone. Arisen during clinical application of the drug questions concerning its biotransformation have predetermined the aim of this research: to study participation liver monooxygenase system in maintenance of histochrome’s pharmacological activity.Simple and informative method of the lifetime control of liver monooxygenase systems influence on a metabolism of a medical product is the estimation of changes of pharmacological effect of a r esearched preparation on a background microsomal oxidations i nhibitor. In experiments on rats chloramphenicol action on diuretic effect of histochrome, as the most convenient for screening, was i nvestigated.To control group of animals during 10 days were hypodermically entered by histochrome in a doze of 10 mg/kg (n = 15. Experimental animals preliminary oral received 50 mg/kg of chloramphenicol before three hours of histochrome introduction (n = 16. In both groups of animals measured volume daily excretion of water, creathinin, sodium and potassium ions excretions in experimental rats each two days. The initial level of parameters of excretory kidneys functions were estimated before introduction of preparations at animals.Long-term histochrome’s injection was followed by a fivefold increasing of water excretion and simultaneously creathinin growth one. Allocation of ions of sodium was statistically significantly increased by 11-th day of experiment, and potassium ions – since the ninth day of histochrome injection. In conditions preliminary chloramphenicol applications volume daily daily urine output and creathinin excretion were essentially less control parameters. Allocation with urine of ions of sodium was decreased almost twice in comparison with the values, fixed at introduction histochrome. Excretion potassium ions ware corresponded to an initial level during all period of supervision.Taking into

  18. Sustaining protein synthesis in the absence of rapid cell division: an investigation of plasmid-encoded protein expression in Escherichia coli during very slow growth.

    Science.gov (United States)

    Flickinger, M C; Rouse, M P

    1993-01-01

    The minimum growth rate capable of supporting plasmid-encoded gene expression is determined using continuous cultures of Escherichia coli MZ9387 at dilution rates (D) as low as 5% of the maximum specific growth rate. Expression from a low copy number plasmid, pMPR166, encoding cyanase under the control of P(lac) is investigated in order to study plasmid-encoded gene expression under conditions approaching starvation. Plasmid copy number was stabilized by selection in the presence of 500 micrograms/mL chloramphenicol by constitutive expression of chloramphenicol acetyl transferase (CAT). Plasmid retention was determined by dot-blot hybridization and chloramphenicol resistance. The contribution of plasmid maintenance and cyanase expression to the maximum cell yield (Y'x/s) and the maintenance coefficient (ms) was determined for MZ9387 and MZ9387:pMPR166 under uninduced and IPTG-induced conditions. The values of Y'x/s and ms for non-plasmid-bearing cultures were 0.56 g of cell dry mass (DCM)/g of glucose and 0.26 g of glucose/g of DCM.h, respectively. The cell yield for plasmid-bearing cultures under uninduced conditions (Y 0'x/s) was 0.28 g of DCM/g of glucose, with m0s = 0.08 g of glucose/g of DCM.h. These values decreased following induction of cyanase expression. Glucose consumption in the presence of IPTG was linearly related to the growth rate at D cyanase expression alters metabolism and glucose consumption. The fraction of plasmid-free cells decreased with decreasing Damköhler number (Da). These data confirm the usefulness of Da for predicting the relationship between plasmid-free and plasmid-bearing cells where plasmids are stabilized by concentrations of antibiotic greater than the minimum plasmid-free host cell growth inhibitory concentration. Specific cyanase expression increased as the dilution rate decreased to D = 0.15 h-1. Between D = 0.15 h-1 and D = 0.14 h-1, expression decreased 7-fold. At very low dilution rates (D < or = 0.06 h-1), nonseptated

  19. Deletion of high pathogenicity island in chromosome of APEC by red recombination%禽致病性大肠埃希菌强毒力岛( HPI)全岛缺失株的构建

    Institute of Scientific and Technical Information of China (English)

    张海峰; 彭开松; 涂健; 祁克宗

    2011-01-01

    Objective To construct E. Coli mutants knockouted the gene encoding high pathogenicity island(HPI) in order to evaluate the function of HPI. Method First, PCR products were obtained by using primers with SO bp extension which were homologous to HPI and by using template plasmid named pKD3 carrying chloramphenicol resistance gene flanked by FRT sites. Then the products were reformed by the program with the pKD46 recombination system replacing high pathogenicity island in the chromosome of E. Coli ZL. Secondy, the strains expressing chloramphenicol resistance gene were selected by chloramphenicol agar. The chloramphenicol resistance gene was then eliminated by using a helper plasmid pCP20. Finally, the purpose gene was identificated and sequenced. Result The constructed mutants were consistent with the expectations. Conclusion The construction of the mutants deleted HPI in chromosome of Escherichia coli was completed successfully.%目的 构建大肠埃希菌强毒力岛(HPI)全岛缺失突变株,为进一步评价大肠埃希菌HPI的功能打下基础.方法 根据已知大肠埃希菌HPI基因序列设计PCR敲除引物,引物5′端有50 bp的拟敲除基因的同源臂,3′端为扩增引物,以pKD3为模板,扩增两侧含FRT位点的氯霉素抗性基因,利用pKD46的λ重组系统替换E.coli ZL基因组上的毒力岛全岛基因,再利用表达Flp重组酶的质粒pCP20,可将FRT位点之间的氯霉素抗性基因删除,用鉴定引物进行鉴定并测序.结果 构建的全岛缺失株与预期一致.结论 成功构建了禽致病性大肠埃希菌强毒力岛(HPI)全岛缺失突变株.

  20. Effects of disinfectants and antibiotics on the anaerobic digestion of piggery waste

    Energy Technology Data Exchange (ETDEWEB)

    Poels, J.; Van Assche, P.; Verstraete, W.

    1984-01-01

    The effects of disinfectants and antibiotics on the anaerobic digestion of piggery waste were investigated. The disinfectants Tego 51, Dettol, NaOCl and Creolin, and the antibiotics, chlortetracyclin, tylosin, erythromycin, chloramphenicol, bacitracin and virginiamycin were tested at different concentrations. At concentrations normally used in practice, no inhibitory effect on methanisation process was detected. However, higher concentrations of the antimicrobial agents, Dettol, Creolin, bacitracin and virginiamycin, markedly inhibited biogas production. In order to minimize possible digester failures, farmers are advised to respect the normal recommended dose and to use low-toxicity antimicrobial agents. (Refs. 8).

  1. Susceptibility of Listeria monocytogenes isolated from food in Italy to antibiotics.

    Science.gov (United States)

    Aureli, Paolo; Ferrini, Anna Maria; Mannoni, Veruscka; Hodzic, Snjezana; Wedell-Weergaard, Christina; Oliva, Brunello

    2003-06-25

    The susceptibility of 148 strains of Listeria monocytogenes isolated from food to antibiotics currently used in veterinary and human therapy was determined by standard agar dilution and disk diffusion methods. The antibiotics included amikacin, amoxicillin, cefazolin, chloramphenicol, erythromycin, flumequine, fosfomycin, gentamicin, kanamycin, lincomycin, oxytetracycline, rifampicin, spiramycin, streptomycin, tetracycline, tobramycin and vancomycin. Soussy's breakpoints and MIC(50)-MIC(90) values were used to classify the strains into sensitive, moderately sensitive and resistant groups. This work is part of a wider surveillance program on listeriosis started in Italy in 1995.

  2. In vitro studies of Dermatophilus congolensis antimicrobial susceptibility by determining minimal inhibitory and bacteriocidal concentrations.

    Science.gov (United States)

    Hermoso de Mendoza, J; Arenas, A; Rey, J; Alonso, J M; Gil, M C; Naranjo, G; Hermoso de Mendoza, M

    1994-01-01

    The Minimal Inhibitory Concentration (MIC) and Minimal Bacteriocidal Concentration (MBC) of 19 antimicrobials on 16 isolates of D. congolensis were determined. The potential field efficacy of the agents was evaluated by comparing the results with serum levels of drug unbound to proteins and the in vitro and in vivo findings of other authors. A modified standard microtechnique was used for serial dilution-antimicrobial sensitivity and found to be easy and reproducible. Erythromycin, spiramycin, penicillin G, ampicillin, chloramphenicol, the streptomycin, amoxicillin, the tetracyclines and novobiocin had high serum concentrations in comparison with their MBCs and were shown to have potential use for the treatment of dermatophilosis.

  3. [In vitro antibiotic sensitivity of French strains of Mycoplasma bovis].

    Science.gov (United States)

    Poumarat, F; Martel, J L

    1989-01-01

    The in vitro activity of 15 antibiotics was tested with 30-90 Mycoplasma bovis representative strains of bovine lung pathology in France. The distribution of minimal inhibitory concentration (MIC) is homogeneous with low values for spectinomycin, lincomycin, tylosin, gentamicin and baytril, intermediate for chloramphenicol and neomycin, high for nalidixic acid, Flumequine and erythromycin. The MIC distribution is heterogeneous with intermediate values for spiramycin and tetracyclines, and high values for streptomycin. For the later antibiotics, the heterogeneity of the susceptibility suggests a mechanism of acquired resistance.

  4. Neuroinfections due to Enterococcus faecalis in children.

    Science.gov (United States)

    Benca, J; Ondrusova, A; Huttova, M; Rudinsky, B; Kisac, P; Bauer, F

    2007-06-01

    Enterococcal meningitis is a rare complication of neurosurgical procedure or high technology treatment of children and occurs mainly imunocompromised neonates with very low birth weight, severe prematurity and complicates sometime ventriculoperitoneal shunt insertion or perinatal trauma. E. faecalis caused 10 nosocomial meningitis and all strains were susceptible to vancomycin and chloramphenicol, and in our database 90% also to gentamicin and ampicillin. Mortality in our group of 10 children was 20% what is insignificantly higher than overall mortality in the whole cohort of meningitis within last 15 years in our database (15.1%). Early empiric therapy should include also ampicillin or vancomycin, if enterococcal etiology is suspected.

  5. Extended Spectrum Beta Lactamase producing Cephalosporin resistant Salmonella Typhi, reported from Rawalpindi, Pakistan.

    Science.gov (United States)

    Munir, Tehmina; Lodhi, Munir; Ansari, Jawad Khaliq; Andleeb, Saadia; Ahmed, Mushtaq

    2016-08-01

    Typhoid is endemic in many parts of southeast Asia. Due to the resistance of the organism to first line of antibiotics (ampicillin, chloramphenicol, cotrimoxazole) as well as to fluoroquinolones, third generation cephalosporins have been in use for the empiric treatment of typhoid for years. However an increasing incidence of Salmonella Typhi is being reported sporadically from various regions. We report a case of typhoid due to Salmonella Typhi which was non-responsive to treatment with a cephalosporin, was found to be multidrug resistant and resistant to ciprofloxacin and third generation cephalosporin as well. The patient was finally treated successfully with intravenous administration of a carbapenem.

  6. Revised ciprofloxacin breakpoints for Salmonella Typhi: its implications in India.

    Science.gov (United States)

    Balaji, V; Sharma, A; Ranjan, P; Kapil, A

    2014-01-01

    The rise of multidrug resistant strains of Salmonella Typhi in the last decade of the previous century led to the use of fluoroquinolones as the drug of choice. However, over the past few years fluoroquinolone resistance has been increasingly reported. In accordance with the revised Clinical and Laboratory Standards Institute (CLSI) breakpoints, only 3% of the isolates were susceptible to ciprofloxacin in comparison to 95% as per the earlier guidelines when 488 isolates collected between 2010 and 2012 were re-interpreted. Interestingly, re-emergence of strains susceptible to chloramphenicol, ampicillin and cotrimoxazole is being seen. Amidst the changing susceptibility profile, azithromycin remains a promising alternative.

  7. Sensibilidade antimicrobiana de amostras de Escherichia coli isoladas de leitões com diarréia após o desmame

    Directory of Open Access Journals (Sweden)

    Benito Guimarães de Brito

    2000-01-01

    Full Text Available The main infectious agent responsible by post-weaning diarrhoea in piglets is the Escherichia coli and the therapy by drugs is used for control of this disease. The antimicrobial sensitivity of 66 strains of Escherichia coli isolated from piglets with post-weaning diarrhoea was studied. The results show high resistance at four drugs (streptomycin, sulfonamide, tetracycline and chloramphenicol. Gentamycin and neomycin were the best antimicrobial in the inhibition of strains of Escherichia coli, isolated from piglets with post-weaning diarrhoea, in the southwest of Paraná.

  8. Emergence and characterisation of vanB vancomycin-resistant Enterococcus faecalis in Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Vânia Lúcia Carreira Merquior

    2012-06-01

    Full Text Available Here we describe the detection and characterisation of three isolates of vancomycin-resistant VanB-type Enterococcus faecalis. Sequence analysis suggested that these isolates harboured the vanB1 gene. The isolates were susceptible to the majority of antimicrobial agents tested, with the exception of chloramphenicol, erythromycin and vancomycin, and showed distinct profiles of high-level resistance to aminoglycosides. Analysis of the clonal relatedness of the vanB E. faecalis isolates showed similar pulsed-field gel electrophoresis profiles. To our knowledge, this is the first report of the occurrence of enterococcal strains carrying vanB genes in Brazil.

  9. Plasmid-determined resistance to fosfomycin in Serratia marcescens.

    Science.gov (United States)

    Mendoza, C; Garcia, J M; Llaneza, J; Mendez, F J; Hardisson, C; Ortiz, J M

    1980-08-01

    Multiple-antibiotic-resistant strains of Serratia marcescens isolated from hospitalized patients were examined for their ability to transfer antibiotic resistance to Escherichia coli by conjugation. Two different patterns of linked transferable resistance were found among the transconjugants. The first comprised resistance to carbenicillin, streptomycin, and fosfomycin; the second, and more common, pattern included resistance to carbenicillin, streptomycin, kanamycin, gentamicin, tetracycline, chloramphenicol, sulfonamide, and fosfomycin. The two types of transconjugant strains carried a single plasmid of either 57 or 97 megadaltons in size. Both of these plasmids are present in parental S. marcescens strains resistant to fosfomycin. The 57-megadalton plasmid was transformed into E. coli.

  10. Studies on phytoplankton-bacterial interactions

    Digital Repository Service at National Institute of Oceanography (India)

    DeCosta, P.M.

    L -1 for streptomycin, and 0.02 mg mL -1 for chloramphenicol]. 3X and 2X were considered high concentrations, X – moderate concentration and X/10 - low concentration. When bacteria were suppressed to 1-17% in the penicillin treatments... suppressed by penicillin, only Odontella aurita emerged in the high penicillin (2P) treatment, an unidentified diatom and Nitzschia sp. in the moderate penicillin (P) treatment, and A. rostrata and an unidentified diatom in the low penicillin (P/10...

  11. Catalase-negative Staphylococcus aureus isolated from a diabetic foot ulcer

    Directory of Open Access Journals (Sweden)

    MR Zali

    2010-12-01

    Full Text Available We report a catalase-negative Staphylococcus aureus isolated from a 56-year-old male diabetic patient with foot ulcer who attended our surgery ward. Species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc and fem genes. Antibiotic susceptibility showed that the strain was sensitive to imepenem, chloramphenicol, amoxicillin, vancomycin and resistant to oxacillin, penicillin, ceftriaxone, erythromycin, clindamycin, and amikacin. Clinicians and microbiologists must be encouraged to identify and report these atypical strains and the infections associated with them in order to establish their role in pathogenesis.

  12. Cytoplasmic sequences of the growth hormone receptor necessary for signal transduction

    DEFF Research Database (Denmark)

    Goujon, L; Allevato, G; Simonin, G

    1994-01-01

    -dependent genes encoding ovine beta-lactoglobulin or serine protease inhibitor 2.1 (Spi 2.1, formerly Spi.1; the corresponding rat gene has recently been redesignated Spin2a) coupled to the bacterial reporter gene encoding chloramphenicol acetyltransferase (CAT). Transfected cells were grown in the absence...... family. Alanine substitutions for the four prolines of GHR Box I were introduced. Single proline-to-alanine mutations did not affect the functional activity of the GHR. However, modification of the four prolines together or deletion of the Box I (15 amino acids between positions 279 and 293) resulted...

  13. Lactobacillus farciminis MD, a newer strain with potential for bacteriocin and antibiotic assay.

    Science.gov (United States)

    Halami, P M; Chandrashekar, A; Nand, K

    2000-03-01

    A native isolate Lactobacillus farciminis MD isolated from fermenting mushroom exhibited a high degree of sensitivity to the majority of the bacteriocins produced by strains of lactobacilli, leuconostoc and pediococci. Also, the efficacy of Lact. farciminis MD as a sensitive strain for antibiotic assay was established against different antibiotics including ampicillin, cefazoline, chloramphenicol and nitrofurantoin at concentrations of 30 microg each, showing an inhibition zone of 30 mm diameter. The high degree of sensitivity towards bacteriocins and antibiotics provide potential for the exploitation of Lact. farciminis MD in establishing very well-defined bacteriocin producers.

  14. TERMINALIA CHEBULA: A TREATMENT AGAINST PATHOGENIC PROTEUS VULGARIS STRAINS ASSOCIATED WITH URINARY TRACT INFECTION

    OpenAIRE

    Tariq. A. L; Reyaz. A. L

    2013-01-01

    Terminalia chebula was used to find out the new sort of treatment for the urinary tract infections caused by Proteus vulgaris. The causative agent was identified as Proteus vulgaris by staining and biochemical methods. It is responsible to cause urinary tract infection and most of strains show the resistance against the broad spectrum antibiotics: Ceftazidime (30μg), Ofloxacin (50μg), Norfloxacin (30μg), Tetracycline (30μg), Ampicillin (30μg), Chloramphenicol (25μg) and Gentamycin (20μg). The...

  15. Genetic control of prophage induction in Haemophilus influenzae after exposure to psoralen plus near-uv light

    Energy Technology Data Exchange (ETDEWEB)

    George, M.; Notani, N.K.

    1980-09-01

    Prophage S2 could be induced by psoralen plus near-uv light (PNUV) from a wild-type strain of Haemophilus influenzae, from uv light-sensitive strains uvr-1 and uvr-2, and PNUV-sensitive strains PSO1 and PSO7, but not from a recombination-deficient strain, rec-1. The levels of prophage induction were comparable in the wild type and an ATP-dependent DNase-deficient strain, KW31, even though the PNUV-induced degradation in the latter strain was considerably lower. Prophage induction could be observed even with chloramphenicol present before, during, and 30 min after PNUV treatment.

  16. Inducible repair system in Haemophilus influenzae unaccompanied by mutation. [uv

    Energy Technology Data Exchange (ETDEWEB)

    Notani, N.K.; Setlow, J.K.

    1980-07-01

    Weigle reactivation of ultraviolet-irradiated HPlc1 phage was observed after ultraviolet or mitomycin C treatment of Haemophilus influenzae cells. The amount of reactivation was considerably increased when the treated cells were incubated in growth medium before infection. The presence of chloramphenicol during this incubation abolished the reactivation. No mutation of this phage accompanied the reactivation. When cells were treated so as to produce a maximal reactivation of phage, neither reactivation nor mutation of cells was observed. It is concluded that H. influenzae has an inducible repair system that is not accompanied by mutation.

  17. Serologic test systems development. Progress report, October 1, 1978-September 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Seawright, G.L.; Sanders, W.M.; Hollstein, U.; Butler, J.E.; Mills, K.W.; Despommier, D.D.; Zimmerman, W.J.; Martinez, E.; Hindman, K.R.; Payne, R.J.

    1980-12-01

    Work has continued on the development and automation of enzyme immunoassays (EIA) for detecting diseases and toxic agents in food animals. Further evaluations were made of the Technicon Autoanalyzer II(AAII) for conducting totally automated EIAs. The problems investigated were machine carryover and assay variation. Modifications greatly reduced or eliminated carryover and produced acceptable levels of test variation. The EIA for swine trichinosis was significantly improved by the use of a new, partially purified antigen preparation. The result was improved detection of early seroconversions and reduced probability for false negatives and false positives. The amplified EIA was adapted as a diagnostic test for bovine brucellosis and studies were initiated for differentiating vaccinated and infected animals. Preliminary data indicate that the IgG/sub 1/ response may be diagnostic but further studies are necessary. Development of the EIA for detecting low molecular weight contaminants and residues in food products was also initiated. Compounds studied were the antibiotics chloramphenicol, tetracycline, and gentamicin; the mycotoxin, aflatoxin, and the shale oil toxin, 2-aminofluorene. Results indicate that chloramphenicol nonspecifically binds to antibody and interferes with antibody activity. Thus, the test is not yet satisfactory. Initial attempts to automate the gentamicin test were unsuccessful because of machine carryover but modifications of the AAII have produced encouraging preliminary data. Work is continuing on the development of EIAs for all of the compounds mentioned above. (ERB)

  18. Effects of dissolved organic matter from a eutrophic lake on the freely dissolved concentrations of emerging organic contaminants.

    Science.gov (United States)

    Xiao, Yi-Hua; Huang, Qing-Hui; Vähätalo, Anssi V; Li, Fei-Peng; Chen, Ling

    2014-08-01

    The authors studied the effects of dissolved organic matter (DOM) on the bioavailability of bisphenol A (BPA) and chloramphenicol by measuring the freely dissolved concentrations of the contaminants in solutions containing DOM that had been isolated from a mesocosm in a eutrophic lake. The abundance and aromaticity of the chromophoric DOM increased over the 25-d mesocosm experiment. The BPA freely dissolved concentration was 72.3% lower and the chloramphenicol freely dissolved concentration was 56.2% lower using DOM collected on day 25 than using DOM collected on day 1 of the mesocosm experiment. The freely dissolved concentrations negatively correlated with the ultraviolent absorption coefficient at 254 nm and positively correlated with the spectral slope of chromophoric DOM, suggesting that the bioavailability of these emerging organic contaminants depends on the characteristics of the DOM present. The DOM-water partition coefficients (log KOC ) for the emerging organic contaminants positively correlated with the aromaticity of the DOM, measured as humic acid-like fluorescent components C1 (excitation/emission=250[313]/412 nm) and C2 (excitation/emission=268[379]/456 nm). The authors conclude that the bioavailability of emerging organic contaminants in eutrophic lakes can be affected by changes in the DOM.

  19. Pathomicrobial studies on Salmonella Gallinarum infection in broiler chickens

    Directory of Open Access Journals (Sweden)

    Divya Kumari,

    2013-08-01

    Full Text Available Aim: To conduct detailed pathomicrobial studies on Salmonella Gallinarum infection in broiler chickens.Materials and Methods: Bacteriological and pathological studies were conducted on 134 dead poultry birds collected from 23 different farms suspected to be infected with S. Gallinarum.Results: Mortality pattern revealed that maximum mortality occurred in 1-2 week aged birds. Out of 23 Salmonella isolates, 19 samples were identified as S. Gallinarum (9, 12 and 4 samples as Salmonella Enteritidis (9, 12: gm. Isolates were found to be most sensitive to Polymyxin B (100%. The present study also showed re-emergence of chloramphenicol sensitivity (83.33%. Pathological lesions observed were bronze discolouration of liver, splenomegaly and necrotic foci on liver, spleen and heart. Microscopically, liver and spleen revealed aggregation of heterophils, lymphocytes and macrophages, non-suppurative myocarditis, fibrinous pericarditis, interstitial nephritis, necrotic enteritis and serofibrinous pneumonia.Conclusion: It was concluded that S. Gallinarum 9, 12 was the main serotype causing Salmonellosis in poultry birds. Polymyxin B was the most sensitive drug (100% for Salmonella infection along with re-emergence of chloramphenicol sensitivity for Salmonella (83.33% infection.

  20. Simultaneous determination of loganin, morroniside, catalpol and acteoside in normal and chronic kidney disease rat plasma by UPLC-MS for investigating the pharmacokinetics of Rehmannia glutinosa and Cornus officinalis Sieb drug pair extract.

    Science.gov (United States)

    Zhao, Min; Tao, Jinhua; Qian, Dawei; Liu, Pei; Shang, Er-xin; Jiang, Shu; Guo, Jianming; Su, Shu-lan; Duan, Jin-ao; Du, Leyue

    2016-01-15

    A sensitive and rapid method for determination of loganin, morroniside, catalpol and acteoside in rat plasma after oral administration of Rehmannia glutinosa Libosch and Cornus officinalis Sieb drug pair based on ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS). Chromatographic separation was achieved using an Acquity UPLC BEH C18 column (100mm×2.1mm, 1.7μm) at a flow rate of 0.4mL/min, using gradient mode containing 0.1% formic acid in water and acetonitrile were used as the mobile phase A and B. Loganin, morroniside, catalpol, acteoside and the internal standard (chloramphenicol) were detected by selected reaction monitoring in the negative ion mode with the mass transition of m/z 451.0→179.0 (morroniside), m/z 435.0→227.0 (loganin), m/z 407.1→199.1 (catalpol), m/z 623.2→161.0 (acteoside) and m/z 320.8→151.9 (chloramphenicol), respectively. All calibration curves showed good linearity (r>0.991). The precision was evaluated by intra-day and inter-day assays and the RSD% were all within 9.58%. The recovery ranged from 67.62 to 80.14%. The method was successfully applied to pharmacokinetic study of the analytes in normal and doxorubicin-induced chronic kidney disease rat plasma.

  1. Prevalence and antimicrobial resistance of Campylobacter in raw milk in the selected areas of Poland.

    Science.gov (United States)

    Wysok, B; Wiszniewska-Łaszczych, A; Uradziński, J; Szteyn, J

    2011-01-01

    During the recent years, an immense increase in the number of food poisoning cases in people caused by Campylobacter (C.) species has occurred. Raw milk, next to poultry meat, is considered the most frequent cause of food poisoning in people caused by the subject bacteria, although it is not always possible to isolate Campylobacter cells from the incriminated milk. Most probably this difficulty is caused by low concentration of the pathogen in milk at the level of 2/3 cells/ml although even such low concentration represents risk to human health. The present study was aimed at determining the occurence of Campylobacter bacteria in milk originating from selected regions of Poland. The isolation method applied in this work was effective in recovering as few as 0.1 cell of Campylobacter per g of food. Among 150 bulk milk samples tested, Campylobacter spp. was isolated from 7 (4.6%) ones. The biochemical identification of the isolated strains conducted by means of conventional biochemical tests as well as by applying the API - Campy tests revealed that all the isolates belonged to the C. jejuni species. Determination of resistance to antibiotics was performed by means of the diffusion disks method for the following antibiotics: gentamicin, ciprofloxacin, ampicillin, chloramphenicol, erythromycin, doxycyclin and tetracycline. Among 7 isolates tested, all were susceptible to ampicillin, chloramphenicol, erythromycin and gentamicin, 28.5% to doxycyclin and 14.2% to tetracycline and ciprofloxacin.

  2. ANTIBIOTIC RESISTANCE IN LACTIC ACID BACTERIA ISOLATED FROM FERMENTED DAIRY PRODUCTS AND BOZA

    Directory of Open Access Journals (Sweden)

    Gamze Başbülbül

    2015-06-01

    Full Text Available In this study, the resistance of 83 strains of lactic acid bacteria isolated from Turkish cheese, yogurt, kefir and boza samples to 6 antibiotics (gentamicin, tetracycline, chloramphenicol, erythromycin, vancomycin and ciprofloxacin was evaluated. The 83 isolates were identified by 16S rRNA gene sequencing and according to BLAST comparisons with sequences in the data banks, those strains showing the highest similarities with the isolates were Enterococcus faecium (10, Lactococcus lactis subsp. Lactis (10, Lactobacillus fermentum (6, Lactobacillus plantarum (6, Lactobacillus coryniformis (7, Lactobacillus casei (13, Leuconostoc mesenteroides (14, Pediococcus pentosaceus (10, Weisella confusa (7. Antimicrobial resistance of strains to 6 antibiotics was determined using the agar dilution method. The antibiotic resistance among all the isolates was detected against chloramphenicol (31,3 % of the isolates, tetracycline (30,1 %, erythromycin (2,4 %, ciprofloxacin (2,41%, vancomycin (73,5 %, intrinsic resistance. Overall 19,3 % of the isolates showed resistance against multiple antibiotics. Antibiotic resistance genes were studied by PCR and the following genes were detected; tet(M gene in Lactobacillus fermentum (1, Lactobacillus plantarum (1, Pediococcus pentosaceus (5, Enterococcus faecium (2, Weisella confusa (4 and the vancomycin resistance gene van(A in one Weisella confusa strain.

  3. [Analysis of pollution levels of 16 antibiotics in the river water of Daliao River water system].

    Science.gov (United States)

    Yang, Changqing; Wang, Longxing; Hou, Xiaohong; Chen, Jiping

    2012-08-01

    The detection of the pollution level of antibiotics in Daliao River system is a meaningful work. Sixteen antibiotics (6 sulfonamides, 5 fluoroquinolones, 3 tetracyclines and 2 chloramphenicols) were simultaneously quantified with solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). In the SPE procedure, methanol and 2% (v/v) ammonia/methanol were used as the elution solvents in sequence to reduce the elution volume and improve the recovery. The results showed that this method have good sensitivity and enrichment effect for the target antibiotics in aqueous water, the recoveries ranged from 69.5% to 122.6%, the detection limits ranged from 0.05 ng/L to 0.32 ng/L. Thirteen antibiotics were found in the river water of Daliao River water system. Sulfa antibiotics were widely distributed, in which sulfamethoxazole was detected in all the sampling sites. The concentration of fluoroquinolones was relatively high in some sampling sites. The highest detection concentration of enoxacin was 41.3 ng/L. The frequencies and concentrations of tetracyclines and chloramphenicols were lower. In the upper reaches of the river, the concentrations of the 4 types of antibiotics appeared lower, but around the large cities such as Shenyang City, Benxi City, Liaoyang City, the concentrations showed higher levels. The study indicated that the Daliao River water system suffered from the pollution of antibiotics to a certain extent.

  4. Methicillin-Resistant Staphylococcus aureus Keratitis after Descemet's Stripping Automated Endothelial Keratoplasty

    Directory of Open Access Journals (Sweden)

    Tatsuro Miyamoto

    2013-11-01

    Full Text Available Purpose: We report a case of methicillin-resistant Staphylococcus aureus (MRSA keratitis after Descemet's stripping automated endothelial keratoplasty (DSAEK. Case Report: An 87-year-old woman who had undergone a DSAEK 4 months previously was referred to Tokushima University Hospital with a diagnosis of infectious keratitis after DSAEK. A white abscess and infiltration in the inferior cornea of the right eye were observed. We started an empiric therapy using topical levofloxacin and chloramphenicol on the basis of the microscopic findings of the corneal scraping concurrently with cultivation of the cornea. Results: A strain of MRSA was isolated from the corneal sample. Although the strain was susceptible to chloramphenicol, it was resistant to quinolone. The keratitis improved rapidly due to empiric therapy, and topical steroids could be resumed 6 days after initiation of the empiric therapy. Conclusions: To our knowledge, this is the first case of MRSA keratitis, and the second case of bacterial keratitis, after DSAEK. MRSA keratitis can occur following uneventful DSAEK. The empiric therapy on the basis of results from a light microscopic examination of a Gram-stained corneal scraping and restarting topical steroids in the early stages of medication contributed to the good clinical course of this case.

  5. Modified artificial diet for rearing of tobacco budworm, Helicoverpa armigera, using the Taguchi method and Derringer's desirability function.

    Science.gov (United States)

    Assemi, H; Rezapanah, M; Vafaei-Shoushtari, R; Mehrvar, A

    2012-01-01

    With the aim to improve the mass rearing feasibility of tobacco budworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), design of experimental methodology using Taguchi orthogonal array was applied. To do so, the effect of 16 ingredients of an artificial diet including bean, wheat germ powder, Nipagin, ascorbic acid, formaldehyde, oil, agar, distilled water, ascorbate, yeast, chloramphenicol, benomyl, penicillin, temperature, humidity, and container size on some biological characteristics of H. armigera was evaluated. The selected 16 factors were considered at two levels (32 experiments) in the experimental design. Among the selected factors, penicillin, container size, formaldehyde, chloramphenicol, wheat germ powder, and agar showed significant effect on the mass rearing performance. Derringer's desirability function was used for simultaneous optimization of mass rearing of tobacco budworm, H. armigera, on a modified artificial diet. Derived optimum operating conditions obtained by Derringer's desirability function and Taguchi methodology decreased larval period from 19 to 15.5 days (18.42 % improvement), decreased the pupal period from 12.29 to 11 days (10.49 % improvement), increased the longevity of adults from 14.51 to 21 days (44.72 % improvement), increased the number of eggs/female from 211.21 to 260, and increased egg hatchability from 54.2% to 72% (32.84 % improvement). The proposed method facilitated a systematic mathematical approach with a few well-defined experimental sets.

  6. ANTIBIOTIC RESISTANCE OF ESCHERICHIA COLI ISOLATED FROM UKRAINIAN BETULA VERRUCOSA EHRH. POLLEN AFTER MICROBIOLOGICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Tetiana Shevtsova

    2013-08-01

    Full Text Available Seven samples of silver birch pollen from different habitat of Ukraine were investigated in order to estimate their contamination with the Enterobacteriaceae family, anaerobic bacteria and fungi. Also resistance of 108 strains of Escherichia coli isolated from seven samples of Ukrainian Betula verrucosa Ehrh. pollen against 5 antibiotics: ampicillin, chloramphenicol, meropenem, ceftriaxone and ofloxacin were determined. Disc diffusion method was used for antibiotic suceptibility testing according to EUCAST 2012. It is established the concentrations of enterobacteria ranged from 0.00 to 4.16 log cfu/g, of anaerobic bacteria – 2.48 to 4.90 log cfu/g and concentration of fungi ranged from 2.48 to 4.14 log cfu/g. Degree of pollen contamination is different depending on the habitats. The resistance of E. coli isolates was determined against ampicillin, chloramphenicol, meropenem and ofloxacin. But intermediate resistance in the 33.3% of E. coli isolates and susceptibility in the 8.3% to ceftriaxone was found out. Antibiotic resistance was evaluated for all samples of pollen in whole.

  7. Antimicrobial resistance of coagulase-negative staphylococci and lactic acid bacteria from industrially produced dairy products

    Directory of Open Access Journals (Sweden)

    Nevijo Zdolec

    2013-03-01

    Full Text Available In this research, the susceptibility to clindamycin, tetracycline, amikacin, amoxicillin + clavulanic acid, enrofloxacine, vancomycin, trimethoprim + sulphametoxazol, tobramycin, chloramphenicol, ciprofloxacin, erythromycin, penicillin and trimethoprim was tested in coagulase-negative staphylococci (n=78 and lactic acid bacteria (n=30 by means of disk diffusion test and E-test. The isolates were collected from soft and hard cheeses, butter and brine. All isolates of coagulase-negative staphylococci were susceptible to clindamycin, amikacin, amoxicillin + clavulanic acid, enrofloxacine, vancomycin, chloramphenicol and ciprofloxacin according to CLSI breakpoints. A total of 30 staphylococci isolates (38.46 % were resistant to erythromycin, 18 to penicillin (23.07 %, 4 to tetracycline (5.12 %, and one isolate to trimethoprim, tobramicin and trimethoprim + sulphametoxazol (1.28 %. Among 78 tested staphylococci, 35 of them were resistant to at least one antimicrobial substance (44.87 %. The rate of resistant isolates of different soft cheese types ranged from 22 to 70 %, while resistant staphylococci were absent in hard cheese and brine. The growth of lactic acid bacteria was not influenced by trimethoprim + sulphametoxazol (n=29, vancomycin (n=29, trimethoprim (n=28, amikacin (n=10 and tobramycin (n=10. The results show that significant part of apathogenic microbiota in different dairy products is phenotypically resistant to antimicrobial agents.

  8. Denitrification in soil amended with thermophile-fermented compost suppresses nitrate accumulation in plants.

    Science.gov (United States)

    Ishikawa, Kazuto; Ohmori, Takashi; Miyamoto, Hirokuni; Ito, Toshiyuki; Kumagai, Yoshifumi; Sonoda, Masatoshi; Matsumoto, Jirou; Miyamoto, Hisashi; Kodama, Hiroaki

    2013-02-01

    NO (3) (-) is a major nitrogen source for plant nutrition, and plant cells store NO (3) (-) in their vacuoles. Here, we report that a unique compost made from marine animal resources by thermophiles represses NO (3) (-) accumulation in plants. A decrease in the leaf NO (3) (-) content occurred in parallel with a decrease in the soil NO (3) (-) level, and the degree of the soil NO (3) (-) decrease was proportional to the compost concentration in the soil. The compost-induced reduction of the soil NO (3) (-) level was blocked by incubation with chloramphenicol, indicating that the soil NO (3) (-) was reduced by chloramphenicol-sensitive microbes. The compost-induced denitrification activity was assessed by the acetylene block method. To eliminate denitrification by the soil bacterial habitants, soil was sterilized with γ irradiation and then compost was amended. After the 24-h incubation, the N(2)O level in the compost soil with presence of acetylene was approximately fourfold higher than that in the compost soil with absence of acetylene. These results indicate that the low NO (3) (-) levels that are often found in the leaves of organic vegetables can be explained by compost-mediated denitrification in the soil.

  9. Effects of antibiotics on Shiga toxin 2 production and bacteriophage induction by epidemic Escherichia coli O104:H4 strain.

    Science.gov (United States)

    Bielaszewska, Martina; Idelevich, Evgeny A; Zhang, Wenlan; Bauwens, Andreas; Schaumburg, Frieder; Mellmann, Alexander; Peters, Georg; Karch, Helge

    2012-06-01

    The role of antibiotics in treatment of enterohemorrhagic Escherichia coli (EHEC) infections is controversial because of concerns about triggering hemolytic-uremic syndrome (HUS) by increasing Shiga toxin (Stx) production. During the recent large EHEC O104:H4 outbreak, antibiotic therapy was indicated for some patients. We tested a diverse panel of antibiotics to which the outbreak strain is susceptible to interrogate the effects of subinhibitory antibiotic concentrations on induction of stx(2)-harboring bacteriophages, stx(2) transcription, and Stx2 production in this emerging pathogen. Ciprofloxacin significantly increased stx(2)-harboring phage induction and Stx2 production in outbreak isolates (P values of 0.1) and chloramphenicol, meropenem, azithromycin, rifaximin, and tigecycline significantly decreased them (P ≤ 0.05). Ciprofloxacin and chloramphenicol significantly upregulated and downregulated stx(2) transcription, respectively (P antibiotics had insignificant effects (P > 0.1). Meropenem, azithromycin, and rifaximin, which were used for necessary therapeutic or prophylactic interventions during the EHEC O104:H4 outbreak, as well as tigecycline, neither induced stx(2)-harboring phages nor increased stx(2) transcription or Stx2 production in the outbreak strain. These antibiotics might represent therapeutic options for patients with EHEC O104:H4 infection if antibiotic treatment is inevitable. We await further analysis of the epidemic to determine if usage of these agents was associated with an altered risk of developing HUS.

  10. AXENIC CULTURE OF FREE-LIVING CONCHOCELIS OF PORPHYRA YEZOENSIS AND PORPHYRA HAITANENSIS

    Institute of Scientific and Technical Information of China (English)

    刘会莲; 帅莉; 段德麟; 徐怀恕

    2002-01-01

    After discarding marine microorganisms from conchocelis of Porphyra yezoensis and Porphyra haitanensis, their axenic cultures were obtained through treatment with antibiotics. Antibiotic disc tests were carried out to determine the effectiveness of each antibiotic in eliminating contaminating microorganisms. Five of 12 antibiotics tested were selected and used to produce the axenic cultures in this study, which showed that 200 μg/mL streptomycin, 250 μg/mL penicillin, 252 μg/mL kanamycin, 30 μg/mL neomycin, 200 μg/mL chloramphenicol were effective concentrations for eliminating microorganisms from conchocelis when antibiotics were added singly step by step; whereas simultaneous combination of 150 μg/mL streptomycin, 250 (or 350) μg/mL penicillin, 150 (or 250) μg/mL kanamycin, 70 μg/mL neomycin and 200 μg/mL chloramphenicol was also effective for producing the axenic cultures. However, it seemed that the treatments with antibiotics applied individually were more feasible than those with all antibiotics added at the same time. This may be due to the combined inhibiting effect of antibiotics on the growth and development of conchocelis.

  11. Antibiotic susceptibility of body surface and gut micro flora of two aquatic leech species (Hirudinaria manillensis and Hirudinaria javanica) in Malaysia

    Institute of Scientific and Technical Information of China (English)

    Parimannan Sivachandran; Kasi Marimuthu; Manickam Ravichandran; Jesu Arockiaraj

    2013-01-01

    Objective: To elucidate the antibiotic susceptibility of body surface and gut associated microflora of two local aquatic leech species Hirudinaria manillensis and Hirudinaria javanica.Methods:Four commercially available antibiotics (doxycycline, chloramphenicol, tetracycline and ciprofloxacin) were used in this study. A total of 13 isolated gut and two surface micro flora from Hirudinaria manillensis and two gut and two surface micro flora from Hirudinaria javanica were tested for their antibiotic susceptibility. Results: Based on the susceptibility, it was observed that all the isolated bacteria were found to be susceptible to at least three of the antibiotics except Microbacterium resistens, Serratiamarcescens and Morganella morganii. This study also found that the bacterial species Bacillus fusiformis has displayed resistance against tetracycline and Tsukamurella inchonensis against chloramphenicol.Conclusions:Among all the antibiotics tested, ciprofloxacin was found to be the best bactericidal agent. The immersion of leeches in ciprofloxacin before the application to the patient may be beneficial to prevent invasive infection of the patient. Further study is needed to sterilize the live leech by immersion/oral mode of administration for the tested antibiotics.

  12. Antibiotic susceptibility of body surface and gut micro flora of two aquatic leech species (Hirudinaria manillensis and Hirudinaria javanica in Malaysia

    Directory of Open Access Journals (Sweden)

    Parimannan Sivachandran

    2013-08-01

    Full Text Available Objective: To elucidate the antibiotic susceptibility of body surface and gut associated microflora of two local aquatic leech species Hirudinaria manillensis and Hirudinaria javanica. Methods: Four commercially available antibiotics (doxycycline, chloramphenicol, tetracycline and ciprofloxacin were used in this study. A total of 13 isolated gut and two surface micro flora from Hirudinaria manillensis and two gut and two surface micro flora from Hirudinaria javanica were tested for their antibiotic susceptibility. Results: Based on the susceptibility, it was observed that all the isolated bacteria were found to be susceptible to at least three of the antibiotics except Microbacterium resistens, Serratia marcescens and Morganella morganii. This study also found that the bacterial species Bacillus fusiformis has displayed resistance against tetracycline and Tsukamurella inchonensis against chloramphenicol. Conclusions: Among all the antibiotics tested, ciprofloxacin was found to be the best bactericidal agent. The immersion of leeches in ciprofloxacin before the application to the patient may be beneficial to prevent invasive infection of the patient. Further study is needed to sterilize the live leech by immersion/oral mode of administration for the tested antibiotics.

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

    Directory of Open Access Journals (Sweden)

    M.R. Prado

    2006-12-01

    Full Text Available A total of 22 clinical specimens were obtained from 19 dogs with corneal ulcer (16 unilateral and three bilateral for isolation and antimicrobial susceptibility evaluation of the isolated bacteria. Bacterial growth was observed in 100% of the samples (n=22. Staphylococcus intermedius was the predominant species (35.5%, followed by Corynebacterium xerosis (19.3%. Gentamicin, ciprofloxacin, chloramphenicol and tobramycin had a high efficacy against all of the isolated bacteria. The results evidenced that 80.7% of the isolates were Gram positive cocci and Gram positive bacilli, and that those microorganisms were sensitive to gentamicin, ciprofloxacin, chloramphenicol and tobramycin.Utilizaram-se 22 amostras de material, obtidas de 19 cães com úlcera de córnea, sendo 16 unilaterais e três bilaterais, para isolamento e avaliação da susceptibilidade antimicrobiana das bactérias isoladas. Observou-se crescimento bacteriano em 100% das amostras (n=22. A espécie predominante foi Staphylococcus intermedius (35,5% seguido de Corynebacterium xerosis (19,3%. Gentamicina, ciprofloxacina, cloranfenicol e tobramicina apresentaram alta eficácia contra todas as bactérias isoladas. Os resultados evidenciam que 80,7% dos isolados foram cocos e bacilos Gram positivos e que estes microrganismos foram sensíveis à gentamicina, ciprofloxacina, cloranfenicol e tobramicina.

  14. Antimicrobial resistance trends among Salmonella isolates obtained from horses in the northeastern United States (2001-2013).

    Science.gov (United States)

    Cummings, Kevin J; Perkins, Gillian A; Khatibzadeh, Sarah M; Warnick, Lorin D; Aprea, Victor A; Altier, Craig

    2016-05-01

    OBJECTIVE To describe the antimicrobial resistance patterns of Salmonella isolates obtained from horses in the northeastern United States and to identify trends in resistance to select antimicrobials over time. SAMPLE 462 Salmonella isolates from horses. PROCEDURES Retrospective data were collected for all Salmonella isolates obtained from equine specimens that were submitted to the Cornell University Animal Health Diagnostic Center between January 1, 2001, and December 31, 2013. Temporal trends in the prevalence of resistant Salmonella isolates were investigated for each of 13 antimicrobials by use of the Cochran-Armitage trend test. RESULTS The prevalence of resistant isolates varied among antimicrobials and ranged from 0% (imipenem) to 51.5% (chloramphenicol). During the observation period, the prevalence of resistant isolates decreased significantly for amoxicillin-clavulanic acid, ampicillin, cefazolin, cefoxitin, ceftiofur, chloramphenicol, and tetracycline and remained negligible for amikacin and enrofloxacin. Of the 337 isolates for which the susceptibility to all 13 antimicrobials was determined, 138 (40.9%) were pansusceptible and 192 (57.0%) were multidrug resistant (resistant to ≥ 3 antimicrobial classes). The most common serovar isolated was Salmonella Newport, and although the annual prevalence of that serovar decreased significantly over time, that decrease had only a minimal effect on the observed antimicrobial resistance trends. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that current antimicrobial use in horses is not promoting the emergence and dissemination of antimicrobial-resistant Salmonella strains in the region served by the laboratory.

  15. Current antimicrobial sensitivity pattern of typhoidal salmonellae in a referral diagnostic centre

    Directory of Open Access Journals (Sweden)

    Umer Shujat

    2016-03-01

    Full Text Available Background: Infections caused by typhoidal salmonellae are an important public health concern in Pakistan. Inappropriate and injudicious use of fluoroquinolones has reduced their efficacy due to development of high level resistance. Aim: To ascertain the current susceptibility pattern of typhoidal salmonellae thus guiding the physicians for better management of typhoid patients.Materials and Methods: A study was conducted at our institution from January 2012 through December 2013 to investigate current susceptibility pattern of typhoidal salmonellae. Results: Out of 200 isolates, 107 (53.5% were identified as Salmonella Typhi and 93 (46.5% as Salmonella Paratyphi A. Sensitivities of Salmonella Typhi were as follows: ampicillin (48.6%, chloramphenicol (45.8%, co-trimoxazole (40.1%, ciprofloxacin (11.2%. Sensitivities of Salmonella Paratyphi A were: ampicillin (80.6%, chloramphenicol (89.2%, co-trimoxazole (90.3%, and ciprofloxacin (16.1%. No resistance was detected against third generation cephalosporins. Conclusions: Typhoidal salmonellae are still entirely susceptible to third generation cephalosporins in our setting. Marked rise in resistance to fluoroquinolones has reduced their empirical usage. Sensitivity of Salmonella Paratyphi A to conventional antityphoid drugs was encouraging.

  16. Biochemical characteristic of biofilm of uropathogenic Escherichia coli Dr(+) strains.

    Science.gov (United States)

    Zalewska-Piątek, Beata; Wilkanowicz, Sabina; Bruździak, Piotr; Piątek, Rafał; Kur, Józef

    2013-07-19

    Urinary tract infections caused by Escherichia coli are very common health problem in the developed countries. The virulence of the uropathogenic E. coli Dr(+) IH11128 is determined by Dr fimbriae, which are homopolymeric structures composed of DraE subunits with the DraD protein capping the fiber. In this study, we have analyzed the structural and biochemical properties of biofilms developed by E. coli strains expressing Dr fimbriae with or without the DraD tip subunit and the surface-exposed DraD protein. We have also demonstrated that these E. coli strains form biofilms on an abiotic surface in a nutrient-dependent fashion. We present evidence that Dr fimbriae are necessary during the first stage of bacterial interaction with the abiotic surface. In addition, we reveal that the DraD alone is also sufficient for the initial surface attachment at an even higher level than Dr fimbriae and that chloramphenicol is able to reduce the normal attachment of the analyzed E. coli. The action of chloramphenicol also shows that protein synthesis is required for the early events of biofilm formation. Additionally, we have identified reduced exopolysaccharide coverage in E. coli that express only Dr fimbrial polyadhesins at the cell surface with or without the DraD capping subunit.

  17. A SAM-dependent methyltransferase cotranscribed with arsenate reductase alters resistance to peptidyl transferase center-binding antibiotics in Azospirillum brasilense Sp7.

    Science.gov (United States)

    Singh, Sudhir; Singh, Chhaya; Tripathi, Anil Kumar

    2014-05-01

    The genome of Azospirillum brasilense harbors a gene encoding S-adenosylmethionine-dependent methyltransferase, which is located downstream of an arsenate reductase gene. Both genes are cotranscribed and translationally coupled. When they were cloned and expressed individually in an arsenate-sensitive strain of Escherichia coli, arsenate reductase conferred tolerance to arsenate; however, methyltransferase failed to do so. Sequence analysis revealed that methyltransferase was more closely related to a PrmB-type N5-glutamine methyltransferase than to the arsenate detoxifying methyltransferase ArsM. Insertional inactivation of prmB gene in A. brasilense resulted in an increased sensitivity to chloramphenicol and resistance to tiamulin and clindamycin, which are known to bind at the peptidyl transferase center (PTC) in the ribosome. These observations suggested that the inability of prmB:km mutant to methylate L3 protein might alter hydrophobicity in the antibiotic-binding pocket of the PTC, which might affect the binding of chloramphenicol, clindamycin, and tiamulin differentially. This is the first report showing the role of PrmB-type N5-glutamine methyltransferases in conferring resistance to tiamulin and clindamycin in any bacterium.

  18. Conjunctival bacterial flora and antibiotic resistance pattern in patients undergoing cataract surgery

    Directory of Open Access Journals (Sweden)

    Arantes Tiago Eugênio Faria e

    2006-01-01

    Full Text Available PURPOSE: To evaluate the conjunctival bacterial flora and its antibiotic resistance pattern in eyes of patients undergoing cataract surgery. METHODS: From August to October 2004, 50 patients undergoing cataract surgery in the "Fundação Altino Ventura", Recife, Brazil, were prospectively evaluated. Conjunctival material was obtained on the day of surgery, before the application of topical anesthetic, antibiotic or povidone-iodine. The collected material was inoculated and bacterioscopic analysis was carried out. In the cases where there was bacterial growth, antibiotic susceptibility tests and cultures, for isolation and identification of the bacteria, were performed. RESULTS: Of the 50 eyes, 43 (86.0% had positive cultures. The coagulase-negative Staphylococcus (CNS, found in 27 (54.0% eyes, was the most frequent organism. More than 90% of the isolates of this bacterium were susceptible to cephalotin, vancomycin, chloramphenicol, ofloxacin and gatifloxacin; 70 to 90% were susceptible to gentamicin, cefotaxime, oxacillin and ciprofloxacin; and less than 70% were sensible to neomycin. Four (10.5% of the bacterial isolates were resistant to four or more antibiotics, two of them were CNS. CONCLUSION: The most frequent bacterium in the conjunctival flora is the coagulase-negative Staphylococcus. The isolates of this organism showed low susceptibility rate to neomycin, and high susceptibility rates to cephalotin, vancomycin, chloramphenicol, ofloxacin and gatifloxacin.

  19. [Antibiotic sensitivity of meningococci isolated from patients and carriers].

    Science.gov (United States)

    Dabernat, H; Delmas, C; Lareng, M B

    1984-06-01

    Ninety-two strains of Neisseria meningitidis (twenty-four recovered from CSF, four from blood, and sixty-four from oropharyngeal swabs) were tested for susceptibility to penicillin, ampicillin, minocycline, chloramphenicol, rifampicin, erythromycin, spiramycin, josamycin, sulphamethoxazole, and trimethoprim. Antibiotic activity (MIC) was determined by agar dilution. Among the 92 cultures, strains were in the following decreasing order: group B, undefined groups, and group C. 75% of strains recovered from carriers and 50% of those recovered from CSF were susceptible to 8 mg/l of sulphamethoxazole. No strain was susceptible to trimethoprim (MIC 8 mg/l). All strains were susceptible to penicillin (range MICs: 0.007-0.25; mean MIC: 0.06), ampicillin (0.015-0.5; 0.12), minocycline (0.03-0.05; 0.25), chloramphenicol (0.12-4; 0.5). and rifampin (0.007-0.25; 0.015). In vitro activity of macrolides was influenced by culture conditions. With 5 to 10% CO2, MICs were 2 to 4 times greater than those culture conditions. With 5 to 10% CO2, MICs were 2 to 4 times greater than those observed without CO2. Josamycin was more active than erythromycin and spiramycin.

  20. [Practical problems raised by antibiotic minimal inhibitory concentration determination in Legionella species (author's transl)].

    Science.gov (United States)

    Bornstein, N; Roudier, C; Fleurette, J

    1982-06-01

    Because of culture medium constitution and growth conditions of Legionella species, antibiotic Minimal inhibitory Concentration (MIC) determination is difficult and does not fit with the accepted standards. The following strains have been tested : references strains : Staphylococcus aureus Oxford CNCM 53154, S. aureus 209P CNCM 53156, E. coli CNCM A224, E. coli CNCM 7324. L. pneumophila, 9 strains representative of the 6 serogroups. L. micdadei, L. dumoffii. 5 clinical isolates of L. pneumophila serogroup 1 (3 isolated in our Laboratory and 2 in Belgium). MIC of 17 antibiotics have been determined, among them macrolids not tested before. The method used was the Agar Dilution Method, with several media compared. MIC values are different in function of the various media tested Charcoal yeast extract medium, which is recommended for Legionella growth, does not inhibit activity of penicillin G, cefalotin, cefoxitin, amikacin, erythromycin and lincosamins, in contrast of tetracyclin, gentamicin, dibekacin, chloramphenicol, oleandomycin, pristinamycin, spiramycin and rifampicin. Charcoal, ferric pyrophosphate and L-cystein present in the culture medium are inactivating factors. However our results confirm good activity of rifampicin, erythromycin, cefoxitin, chloramphenicol, gentamicin and amikacin. Among the others macrolids tested, pristinamycin is the most active.

  1. Antibiotic resistance and mechanisms implicated in clinical enterococci in a Tunisian hospital.

    Science.gov (United States)

    Klibi, N; Gharbi, S; Masmoudi, A; Ben Slama, K; Poeta, P; Zarazaga, M; Fendri, C; Boudabous, A; Torres, C

    2006-02-01

    Susceptibility testing for 15 antibiotics was performed in a series of 191 clinical enterococci recovered in a Tunisian Hospital during 2000-2003. Species detected were the following ones (number of isolates): E. faecalis (139), E. faecium (41), E. casseliflavus (5), E. gallinarum (3), E. avium (2) and E. hirae (1). The percentages of antibiotic resistance detected were as follows (E. faecalis/ E. faecium/ other species) : penicillin (0/ 73/ 9%), tetracycline (78/ 44/ 54%), chloramphenicol (52/ 29/ 27%), erythromycin (66/ 100/ 82%), spiramycin (84/ 83/ 64%), pristinamycin (100/ 0/ 73%), trimethoprim-sulfamethoxazole (88/ 78/ 91%), rifampicin (72/ 41/ 0%), vancomycin (0/ 0/ 36%), teicoplanin (0/ 0/ 0%), high-level-resistance for gentamicin (24/ 29/ 45%), streptomycin (34/ 56/ 55%) and kanamycin (41/ 68/ 55%). Increased vancomycin minimum inhibitory concentrations (MICs) were only detected in E. casseliflavus and E. gallinarum isolates (MIC range 8-24 microg/ml). The erm(B), catA, tet(M), aac(6')-aph(2''), aph(3')-IIIa, and ant(6)-Ia genes were detected in 91%, 32%, 86%, 98%, 100%, and 72% of the E. faecium and E. faecalis isolates resistant to erythromycin, chloramphenicol, tetracycline and high-level-resistant to gentamicin, kanamycin and streptomycin, respectively. A total of 20 unrelated pulsed-field-gel-electrophoresis patterns were found in the series of 46 high-level gentamicin-resistant E. faecalis and E. faecium isolates of this study.

  2. Bacterial Flora from Healthy Clarias gariepinus and their Antimicrobial Resistance Pattern

    Directory of Open Access Journals (Sweden)

    M.O. Efuntoye

    2012-06-01

    Full Text Available The antibiotic resistance of bacteria isolated from Clarias gariepinus from 3 farms in Ago-Iwoye, Nigeria was investigated. Morphological and biochemical characteristics of isolates revealed that majority of the bacteria belonged to the family Enterobacteriaceae. Staphylococcus aureus and Pseudomonas aeruginosa were also recovered. E. coli strains were highly resistant to ampicillin, chloramphenicol and oxytetracycline (82.4%. Majority of the Pseudomonas aeruginosa were resistant to ampicillin (63.6%, amoxycillin (54.5%, nalidixic acid (63.6% and oxytetracycline (72.7%, whereas most of the Salmonella spp. were resistant to erythromycin (85.7%, gentamycin (71.4%, amoxicillin (57.1%, chloramphenicol (57.1% and sulphamethoxazole (57.1%. All isolates were highly sensitive to ciprofloxacin, novobiocin and ofloxacin. While the presence of potentially pathogenic bacterial species as observed in the study may not present a serious human health hazard because of heat treatment accorded fish before consumption, the presence of antibiotic resistant strains should not be ignored because of the potential for horizontal gene transfer in the food chain.

  3. The resistance of Salmonella spp. isolates from Alabio duck against several antibiotics

    Directory of Open Access Journals (Sweden)

    Istiana

    1998-06-01

    Full Text Available A total of 172 isolates of Salmonella spp. consisted of S. typhimurium (70, S. Radar (52, S. senftenberg (25, S. Virchow (14, and S. amsterdam (11 from Alabio duck hatcheries in the District of Hulu Sungai Utara, South Kalimantan, were examined their resistencies against seven kinds of antibiotics, consisted of chloramphenicol, neomycin, trimethoprim, streptomycin, tetracycline, ampicillin, and polymixin B, by using agar disc diffusion method. The results showed that 70 isolates of S. typhimurium were resistant against six kinds of antibiotics with various percentages, that is chlorampenicol 5 .7%, neomycin 12 .8%, trimethoprim 7.1 %, streptomycin 8 .6%, tetracycline 11 .4%, and the highest against ampicillin 30 %. Ofthe 52 S. hadar isolates showed that all ofthem were resistent against 6 kinds of antibiotics, that is chloramphenicol 1 .9%, neomycin 7.7%, trimethoprim 5.8%, streptomycin 48 .0%, tetracycline 48.0%, and polymixin B 3.8%. Futhermore S. senftenberg (25 isolates were resistent against three kinds of antibiotics, that is neomycin 12%, streptomycin 20%, and tetracyclines 16%. Meanwhile S. virchow (14 isolates, were resistant against two kinds of antibiotics namely streptomycin 7.1% and tetracylines 14.3%. Whereas S. amsterdam (11 isolates were resistant against four kinds of antibiotics, that is neomycin 45 .5%, streptomycin 18 .2%, tetracycline 18 .2%, and ampicillin 9.10%.

  4. Aerobic nitroreduction of dehydrochloramphenicol by bone marrow.

    Science.gov (United States)

    Isildar, M; Abou-Khalil, W H; Jimenez, J J; Abou-Khalil, S; Yunis, A A

    1988-06-30

    It has been previously demonstrated that dehydrochloramphenicol (DH-CAP), a bacterial metabolite of chloramphenicol, induces DNA single strand breaks in intact cells and is profoundly more cytotoxic than chloramphenicol (CAP). In view of previous observations relating genotoxicity of nitrocompounds to their nitroreduction by the target tissue, we studied the nitroreduction of DH-CAP by human and rabbit bone marrow. Nitroreduction by tissue homogenates was determined by the Bratton Marshall colorimetric assay and by high-performance liquid chromatography (HPLC). Nitroreduction of DH-CAP by bone marrow cell homogenates was observed under aerobic conditions and the reduction was both cell concentration- and time-dependent. The formation of the amino product aminodehydrochloramphenicol was confirmed by HPLC. Reduction by other tissues including human liver, Raji cells, and HL-60 tumors was also observed. These results suggest that genotoxicity of DH-CAP may be related to its nitroreduction by the target tissue with in situ production of toxic intermediates. Together with previous studies, these observations lend support to the thesis that the p-NO2 group may be the structural feature underlying aplastic anemia from CAP.

  5. Assessment of antibiotic resistance phenotype and integrons in Salmonella enterica serovar Typhimurium isolated from swine.

    Science.gov (United States)

    Rayamajhi, Nabin; Kang, Sang Gyun; Kang, Mi Lan; Lee, Hee Soo; Park, Kyung Yoon; Yoo, Han Sang

    2008-10-01

    Salmonella enterica serovar Typhimurium (S. Typhimurium) isolated and identified from swine were subjected for the analysis of antibiotic resistance pattern and clinically important class 1 and 2 integrons. In addition, S. Typhimurium isolates exhibiting ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline and florfenicol (ACSSuTF) resistance pattern as described in most Salmonella enterica serotype Typhimurium definitive type 104 (DT104) were characterized by polymerase chain reaction. All the isolates were resistant to more than four antibiotics and showed the highest resistance to streptomycin (94.1%), followed by tetracycline (90.1%), ampicillin (64.7%), chloramphenicol (56.8%) and gentamicin (54.9%). MIC value for the ten isolates ranged between 0.125-2 mug/ml for ciprofloxacin. Among the beta-lactams used, only one of the isolate exhibited resistance to ceftiofur (MIC 8 microg/ml). Sixty eight percent of these multi drug resistance (MDR) S. Typhimurium isolates carried clinically important class 1 integron with 1kb (aadA) and/or 2kb (dhfrXII-orfF-aadA2) resistance gene cassettes. This study reports the increasing trend of multi drug resistance (MDR) S. Typhimurium with clinically important class 1 integron in pigs. In addition, emergence of the ACSSuTF-type resistance in S. Typhimurium PT other than DT104 may limit the use of resistance gene markers in its detection methods by PCR.

  6. Prevalence of Antibiotic-Resistant Fecal Escherichia coli Isolates from Penned Broiler and Scavenging Local Chickens in Arusha, Tanzania.

    Science.gov (United States)

    Rugumisa, Bernadether T; Call, Douglas R; Mwanyika, Gaspary O; Mrutu, Rehema I; Luanda, Catherine M; Lyimo, Beatus M; Subbiah, Murugan; Buza, Joram J

    2016-08-01

    We compared the prevalence of antibiotic-resistant Escherichia coli isolates from household-level producers of broiler (commercial source breeds) and local chickens in the Arusha District of Tanzania. Households were composed of a single dwelling or residence with independent, penned broiler flocks. Free-range, scavenging chickens were mixed breed and loosely associated with individual households. A total of 1,800 E. coli isolates (1,200 from broiler and 600 from scavenging local chickens) from 75 chickens were tested for their susceptibility against 11 antibiotics by using breakpoint assays. Isolates from broiler chickens harbored a higher prevalence of antibiotic-resistant E. coli relative to scavenging local chickens, including sulfamethoxazole (80.3 versus 34%), followed by trimethoprim (69.3 versus 27.7%), tetracycline (56.8 versus 20%), streptomycin (52.7 versus 24.7%), amoxicillin (49.6 versus 17%), ampicillin (49.1 versus 16.8%), ciprofloxacin (21.9 versus 1.7%), and chloramphenicol (1.5 versus 1.2%). Except for resistance to chloramphenicol, scavenging local chickens harbored fewer resistant E. coli isolates (P < 0.05). Broiler chickens harbored more isolates that were resistant to ≥7 antibiotics (P < 0.05). The higher prevalence of antibiotic-resistant E. coli from broiler chickens correlated with the reported therapeutic and prophylactic use of antibiotics in this poultry population. We suggest that improved biosecurity measures and increased vaccination efforts would reduce reliance on antibiotics by these households.

  7. Untargeted metabolomic profiling of amphenicol-resistant Campylobacter jejuni by ultra-high-performance liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Li, Hui; Xia, Xi; Li, Xiaowei; Naren, Gaowa; Fu, Qin; Wang, Yang; Wu, Congming; Ding, Shuangyang; Zhang, Suxia; Jiang, Haiyang; Li, Jiancheng; Shen, Jianzhong

    2015-02-06

    Campylobacter jejuni, an important foodborne microorganism, poses severe and emergent threats to human health as antibiotic resistance becomes increasingly prevalent. The mechanisms of drug resistance are hard to decipher, and little is known at the metabolic level. Here we apply metabolomic profiling to discover metabolic changes associated with amphenicol (chloramphenicol and florfenicol) resistance mutations of Campylobacter jejuni. An optimized sample preparation method was combined with ultra-high-performance liquid chromatography-time-of-flight mass spectrometry (UHPLC-TOF/MS) and pattern recognition for the analysis of small-molecule biomarkers of drug resistance. UHPLC-triple quadrupole MS operated in multiple reaction monitoring mode was used for quantitative analysis of metabolic features from UHPLC-TOF/MS profiling. Up to 41 differential metabolites involved in glycerophospholipid metabolism, sphingolipid metabolism, and fatty acid metabolism were observed in a chloramphenicol-resistant mutant strain of Campylobacter jejuni. A panel of 40 features was identified in florfenicol-resistant mutants, demonstrating changes in glycerophospholipid metabolism, sphingolipid metabolism, and tryptophan metabolism. This study shows that the UHPLC-MS-based metabolomics platform is a promising and valuable tool to generate new insights into the drug-resistant mechanism of Campylobacter jejuni.

  8. Axenic culture of free-living conchocelis of Porphyra yezoensis and Porphyra haitanensis

    Science.gov (United States)

    Liu, Hui-Lian; Shuai, Li; Duan, De-Lin; Xu, Huai-Shu

    2002-03-01

    After discarding marine microorganisms from conchocelis of Porphyra yezoensis and Porphyra haitanensis, their axenic cultures were obtained through treatment with antibiotics. Antibiotic disc tests were carried out to determine the effectiveness of each antibiotic in eliminating contaminating microorganisms. Five of 12 antibiotics tested were selected and used to produce the axenic cultures in this study, which showed that 200 μg/mL streptomycin, 250 μg/mL penicillin, 252 μg/mL kanamycin, 30 μg/mL chloramphenicol were effective concentrations for eliminating microorganisms from conchocelis when antibiotics were added singly step by step; whereas simultaneous combination of 150 μg/mL streptomycin, 250 (or 350) μg/mL penicillin, 150 (or 250) μg/mL kanamycin, 70 μg/mL neomycin and 200 μg/mL chloramphenicol was also effective for producing the axenic cultures. However, it seemed that the treatments with antibiotics applied individually were more feasible than those will all antibiotics added at the same time. This may be due to the combined inhibiting effect of antibiotics on the growth and development of conchocelis.

  9. SYNERGISTIC EFFECT OF ANTIBIOTICS AND OXYTOCIN IN THE TREATMENT OF ENDOMETRITIS IN MARES

    Directory of Open Access Journals (Sweden)

    M. Ahmad, N. Ahmad. M.K. Mansoor and H.A. Samad

    2001-09-01

    Full Text Available The present study was designed to investigate the effect of oxytocin with or without intrauterine antibiotics infusion, on conception rates in 150 endometritic mares. Uterine swabs were collected from each mare and processed for antibiotic sensitivity tests. Samples from 135 mares showing bacterial growth and antibiotic sensitivity were divided into following groups: Control given oxytocin only, Gentamicin or gentamicin + Oxytocin, Chloramphenicol or Chloramphenicol + Oxytocin, Streptopenicillin + Kanamycin or Streptopenicillin + Kanamycin + Oxytocin and Norfloxacin or Norfloxacin + Oxytocin. After treatment for five days one heat was missed and on second heat mares were bred through natural. mating and examined for pregnancy at least 60 days after service. The overall conception rate in mares of groups treated using antibiotics without oxytocin (62.22% was significantly higher (P<0.05 as compared to 40.00% in the control group. However, conception rates in mares of former groups did not differ from one , another. Similarly. overall conception rate in mares treated using antibiotic + oxytocin combination (82.62% was significantly higher (P<0.05 than overall conception rate in mares treated with antibiotics alone (62.22% or control (40.00%. It was concluded that oxytocin alongwith some suitable antibiotic (s may be used for the treatment of endometritis and improvement of conception rates in endometritic mares

  10. Characterization of Salmonella Enterica Serotype Typhimurium from Outpatients of 28 Hospitals in Henan Province in 2006

    Institute of Scientific and Technical Information of China (English)

    MIN ZHU; ZHI-QIANG XIE; LI-SHI ZHANG; SHENG-LI XIA; WEI-ZHONG YANG; LU RAN; ZI-JUN WANG

    2009-01-01

    Objective To characterize the diarrheal patients with Salmonella typhimurium (S. typhimurium) infections and to set up the first baseline for 5. typhimurium pulsed-field gel electrophoresis (PFGE) patterns in Henan province, thus laying a foundation for comprehensive surveillance of Salmonella in human as well as foods. Methods S. typhimurium isolates recovered from outpatients with diarrhea in Henan province from May to October of 2006 were characterized. Antimicrobial susceptibility tests of 8 antimicrobial agents and PFGE were carried out to analyze the 5. typhimurium isolates. Results Twenty-four (0.9%) S. typhimurium isolates were identified from 2661 stool specimens of diarrheal cases. Eighty-eight percent of isolates showed resistance to at least one antimicrobial agent. The resistance to chloramphenicol (79%) was most common. Fifty-eight percent of isolates were resistant to ciprofloxacin. All the 14 ciprofloxacin-resistant isolates were resistant to more than five antimicrobial agents. Thirty-three percent of 5. typhimurium isolates were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (R-type ACSSuT). Eight antimicrobia-resistant phenotypes were found among the 24 isolates in 16 PFGE patterns. Conclusion The rate of multidrug-resistant S. typhimurium is relatively high in S. typhimurium PFGE patterns of Henan province. Multidrug-resistant S. typhimurium should be considered a public health threat.

  11. Correlation between Infective Factors and Antibiotic Resistance in Enterococci Clinical Isolates in West of Iran

    Science.gov (United States)

    Nasaj, Mona; Mousavi, Seyed Masoud

    2017-01-01

    The present study was done to scrutinize the possible relation between infective genes and antimicrobial resistance in Enterococcus faecalis and Enterococcus faecium. Considering the fact that the presence of recognized infective determinants among clinical isolates may promote the emergence of infections and persistence of Enterococci in hospital settings, which can lead to an increase in antimicrobial resistance. 175 E. faecalis and 67 E. faecium isolated from clinical specimens were used. The isolates were identified, and then antibiotic susceptibility testing was performed. The MIC of vancomycin and teicoplanin were determined by broth microdilution method. The presence of infective genes esp, hyl and asa1 was scrutinized using PCR. Of the 280 enterococcal isolates, 175 (62.5%) isolates were identified as E. faecalis, 67 (24%) as E. faecium and 38 (13.5%) as Enterococcus spp. The results of the antibiotic susceptibility testing showed resistance rates of 5% and 73% to vancomycin and teicoplanin in E. faecalis and E. faecium isolates, respectively. The statistical analysis showed that the esp infective gene has significant associations with ciprofloxacin, erythromycin and tetracycline in E. faecium and with chloramphenicol in E. faecalis strains; the hyl with teicoplanin and vancomycin in E. faecium strains; and also asa1 with vancomycin in E. faecium and with ampicillin and chloramphenicol in E. faecalis strains. Regarding the relationships between virulence genes and antibiotic resistance in strains of E. faecalis and E. faecium, detection of infective factors associated with invasive diseases has become a major issue of concern.

  12. Occurrence of antibiotics in pharmaceutical industrial wastewater, wastewater treatment plant and sea waters in Tunisia.

    Science.gov (United States)

    Tahrani, Leyla; Van Loco, Joris; Ben Mansour, Hedi; Reyns, Tim

    2016-04-01

    Antibiotics are among the most commonly used group of pharmaceuticals in human medicine. They can therefore reach surface and groundwater bodies through different routes, such as wastewater treatment plant effluents, surface runoff, or infiltration of water used for agricultural purposes. It is well known that antibiotics pose a significant risk to environmental and human health, even at low concentrations. The aim of the present study was to evaluate the presence of aminoglycosides and phenicol antibiotics in municipal wastewaters, sea water and pharmaceutical effluents in Tunisia. All analysed water samples contained detectable levels of aminoglycoside and phenicol antibiotics. The highest concentrations in wastewater influents were observed for neomycin and kanamycin B (16.4 ng mL(-1) and 7.5 ng mL(-1), respectively). Chloramphenicol was found in wastewater influents up to 3 ng mL(-1). It was observed that the waste water treatment plants were not efficient in completely removing these antibiotics. Chloramphenicol and florfenicol were found in sea water samples near aquaculture sites at levels up to, respectively, 15.6 ng mL(-1) and 18.4 ng mL(-1). Also aminoglycoside antibiotics were found near aquaculture sites with the highest concentration of 3.4 ng mL(-1) for streptomycin. In pharmaceutical effluents, only gentamycin was found at concentrations up to 19 ng mL(-1) over a sampling period of four months.

  13. Clinically significant anaerobic bacteria isolated from patients in a South African academic hospital: antimicrobial susceptibility testing.

    Science.gov (United States)

    Naidoo, S; Perovic, O; Richards, G A; Duse, A G

    2011-09-27

    BACKGROUND. Increasing resistance to some antimicrobial agents among anaerobic bacteria has made susceptibility patterns less predictable. METHOD. This was a prospective study of the susceptibility data of anaerobic organisms isolated from clinical specimens from patients with suspected anaerobic infections from June 2005 until February 2007. Specimens were submitted to the microbiology laboratory at Charlotte Maxeke Johannesburg Academic Hospital, where microscopy, culture and susceptibility testing were performed the using E test® strip minimum inhibitory concentration method. Results were interpreted with reference to Clinical and Laboratory Standards Institute guidelines for amoxicillin-clavulanate, clindamycin, metronidazole, penicillin, ertapenem, cefoxitin, ceftriaxone, chloramphenicol and piperacillin-tazobactam. RESULTS. One hundred and eighty anaerobic isolates were submitted from 165 patients. The most active antimicrobial agents were chloramphenicol (100% susceptible), ertapenem (97.2%), piperacillin-tazobactam (99.4%) and amoxicillin-clavulanic acid (96.7%). Less active were metronidazole (89.4%), cefoxitin (85%), clindamycin (81.7%), ceftriaxone (68.3%) and penicillin (33.3%). CONCLUSION. Susceptibility testing should be performed periodically to identify emerging trends in resistance and to modify empirical treatment of anaerobic infections.

  14. Antibiotic susceptibility profiles of some Vibrio strains isolated from wastewater final effluents in a rural community of the Eastern Cape Province of South Africa

    Directory of Open Access Journals (Sweden)

    Igbinosa Etinosa O

    2010-05-01

    Full Text Available Abstract Background To evaluate the antibiogram and antibiotic resistance genes of some Vibrio strains isolated from wastewater final effluents in a rural community of South Africa. V. vulnificus (18, V. metschnikovii (3, V. fluvialis (19 and V. parahaemolyticus (12 strains were isolated from final effluents of a wastewater treatment plant (WWTP located in a rural community of South Africa. The disk diffusion method was used for the characterization of the antibiogram of the isolates. Polymerase chain reaction (PCR was employed to evaluate the presence of established antibiotic resistance genes using specific primer sets. Results The Vibrio strains showed the typical multidrug-resistance phenotype of an SXT element. They were resistant to sulfamethoxazole (Sul, trimethoprim (Tmp, cotrimoxazole (Cot, chloramphenicol (Chl, streptomycin (Str, ampicillin (Amp, tetracycline (Tet nalidixic acid (Nal, and gentamicin (Gen. The antibiotic resistance genes detected includes dfr18 and dfrA1 for trimethoprim; floR, tetA, strB, sul2 for chloramphenicol, tetracycline, streptomycin and sulfamethoxazole respectively. Some of these genes were only recently described from clinical isolates, demonstrating genetic exchange between clinical and environmental Vibrio species. Conclusions These results demonstrate that final effluents from wastewater treatment plants are potential reservoirs of various antibiotics resistance genes. Moreover, detection of resistance genes in Vibrio strains obtained from the wastewater final effluents suggests that these resistance determinants might be further disseminated in habitats downstream of the sewage plant, thus constituting a serious health risk to the communities reliant on the receiving waterbodies.

  15. Mycotoxigenic Fungi and Natural Co-Occurrence of Mycotoxins in Rainbow Trout (Oncorhynchus mykiss Feeds

    Directory of Open Access Journals (Sweden)

    Mariana Greco

    2015-11-01

    Full Text Available Samples of rainbow trout feed were analyzed with the aim to determine the mycobiota composition and the co-occurrence of mycotoxins. A total of 28 samples of finished rainbow trout feed from hatcheries in the provinces of Río Negro and Neuquén, Argentina, were studied. Fungal counts were obtained on three culture media in the ranges of <10 to 4.2 × 104 CFU/g on Dichloran Rose Bengal Chloramphenicol Agar (DRBC, <10 to 5.1 × 104 CFU/g on Dichloran Chloramphenicol Peptone Agar (DCPA and <10 to 3.6 × 104 CFU/g on Dichloran 18% Glycerol Agar (DG18. The most frequent mycotoxigenic fungi were Eurotium (frequency (Fr 25.0%, followed by Penicillium (Fr 21.4% and Aspergillus (Fr 3.6%. The most prevalent mycotoxigenic species were E. repens (Fr 21.4% and E. rubrum (Fr 14.3%. All samples were contaminated with mycotoxins: 64% samples were contaminated with T-2 toxin (median 70.08 ppb, 50% samples with zearalenone (median 87.97 ppb and aflatoxins (median 2.82 ppb, 25% with ochratoxin A (median 5.26 ppb and 3.57% samples with deoxynivalenol (median 230 ppb. Eight samples had a fumonisins contamination level below the limit of detection. Co-occurrence of six mycotoxins was determined in 7% of the samples.

  16. Exophiala (Wangiella) dermatitidis and cystic fibrosis - Prevalence and risk factors.

    Science.gov (United States)

    Lebecque, Patrick; Leonard, Anissa; Huang, Daniel; Reychler, Grégory; Boeras, Anca; Leal, Teresinha; Symoens, Françoise

    2010-11-01

    The objective of this prospective study was to assess the prevalence of Exophiala dermatitidis in respiratory secretions of patients with cystic fibrosis (CF) and to identify risk factors for its presence. The results of all cultures performed over a 2-year period in non lung-transplant patients in our CF clinic were included in the study. Samples consisted of sputum (whenever possible) or deep pharyngeal aspirate after a session of physiotherapy. Specimens were inoculated onto Sabouraud gentamicin-chloramphenicol agar (SGCA) medium (Becton-Dickinson) and incubated at 35°C for 2 days and then at ambient temperature (15-25°C) for 3 weeks. The whole study group included 154 patients (mean age ± SD: 18.5 y ± 11.69). E. dermatitidis was isolated from 58 specimens (2.8%) of nine patients (5.8%) out of total of 2065 cultures prepared during the study period. All E. dermatitidis culture-positive patients were pancreatic insufficient and ≥12 y of age. Almost all (8/9) were homozygous for the F508 del mutation. Aspergillus fumigatus colonization and genotype seemed to be predisposing factors. No other significant characteristic was identified in this group, either in terms of predominant bacterial pathogen or treatment. A distinct comparative study performed over 3 months in our laboratory revealed that the use of SGCA yielded identical isolation rates of E. dermatitidis as erythritol-chloramphenicol agar (ECA).

  17. In vitro and in silico Approaches to the Identification of New Compounds with Antibacterial Profile

    Directory of Open Access Journals (Sweden)

    Carlos R. Rodrigues

    2013-06-01

    Full Text Available The emergence of multidrug-resistant bacterial strains is a world problem that increases the need for new and more effective antimicrobials. On that purpose, derivatives of cyclic systems may serve as new leads for discovering new active molecules. In this work we evaluated the antibacterial profile of 243 molecules derived from the systems thienopyridine, pyrazolopiridine, quinolone, chalcone, hydrazone and lapachone against Gram-positive and Gram-negative susceptible and multiresistant strains also comparing them with antibiotics of clinical use. Our results showed that among the 243 molecules tested, only eight derivatives were active with promissing MIC values (2-64mg/mL. Our theoretical in silico analysis showed that all active compounds fulfilled Lipinski rule of five (molecular weight = 344.37–409.24, clogP = 3.15–4.11, nHBA = 6–7, and nHBD = 2, similarly to commercial drugs as well as presented better druglikeness values (from -3.68 to 0.12 than chloramphenicol (-4.61 and linezolid (-4.08. Most of the active derivatives presented a low in silico toxicity risk profile, similar to oxacillin, ampicillin, and penicillin G, and even lower than that observed for chloramphenicol and linezolid. Theoretically HOMO and the electrostatic protential distribution may be contributing for this safer profile. This study used computacional tools and may help to deal with an important world health problem.

  18. Identification of regulatory sequences in the gene for 5-aminolevulinate synthase from rat.

    Science.gov (United States)

    Braidotti, G; Borthwick, I A; May, B K

    1993-01-15

    The housekeeping enzyme 5-aminolevulinate synthase (ALAS) regulates the supply of heme for respiratory cytochromes. Here we report on the isolation of a genomic clone for the rat ALAS gene. The 5'-flanking region was fused to the chloramphenicol acetyltransferase gene and transient expression analysis revealed the presence of both positive and negative cis-acting sequences. Expression was substantially increased by the inclusion of the first intron located in the 5'-untranslated region. Sequence analysis of the promoter identified two elements at positions -59 and -88 bp with strong similarity to the binding site for nuclear respiratory factor 1 (NRF-1). Gel shift analysis revealed that both NRF-1 elements formed nucleoprotein complexes which could be abolished by an authentic NRF-1 oligomer. Mutagenesis of each NRF-1 motif in the ALAS promoter gave substantially lowered levels of chloramphenicol acetyltransferase expression, whereas mutagenesis of both NRF-1 motifs resulted in the almost complete loss of expression. These results establish that the NRF-1 motifs in the ALAS promoter are critical for promoter activity. NRF-1 binding sites have been identified in the promoters of several nuclear genes encoding mitochondrial proteins concerned with oxidative phosphorylation. The present studies suggest that NRF-1 may co-ordinate the supply of mitochondrial heme with the synthesis of respiratory cytochromes by regulating expression of ALAS. In erythroid cells, NRF-1 may be less important for controlling heme levels since an erythroid ALAS gene is strongly expressed and the promoter for this gene apparently lacks NRF-1 binding sites.

  19. Construction of a System for the Stable Expression of Foreign Genes in Dunaliella salina

    Institute of Scientific and Technical Information of China (English)

    GENGDe-Gui; HANYan; WANGYi-Qin; WANGPeng; ZHANGLi-Ming; LIWen-Bin; SUNYong-Ru

    2004-01-01

    A stable transformation system for the expression of foreign genes in the unicellular greenmarine alga (Dunaliella salina Teod.) was established. Using electroporation, the alga was transformed witha plasmid containing the hepatitis B surface antigen (HBsAg) gene and the chloramphenicol acetyltransferase(CAT) gene as a selectable gene. PCR and Southern blotting analysis indicated that the HBsAEgene wasintegrated into the D. salina genome. Northern dotting analysis showed that the HBsAg gene was expressedat the mRNA level. The stable expression of HBsAg protein in transformants was confirmed by HBsAgenzyme-linked immunosorbent assay (HBsAg EUSA) and Western blotting analysis. Also, PCR and Southernblotting analyses showed that the CA Tgene was integrated into the D, salina genome, and CAT EUSAindicated that CAT protein was stably expressed in the cells. The introduced HBsAg DNA and HBsAgprotein expression were stably maintained for at least 60 generations in media devoid of chloramphenicol.This is the first report of the stable expression of foreign genes in D. salina.

  20. Molecular mechanisms of antibiotic resistance in diarrhoeagenic Escherichia coli isolated from children.

    Science.gov (United States)

    Mosquito, Susan; Ruiz, Joaquim; Pons, María J; Durand, David; Barletta, Francesca; Ochoa, Theresa J

    2012-12-01

    Diarrhoeagenic Escherichia coli (DEC) are an important cause of diarrhoea in children and are associated with high antibiotic resistance. However, there are few studies on the molecular mechanisms of resistance in this group of bacteria. The aim of this study was to determine the mechanisms associated with antibiotic resistance in the most common phenotypes of DEC. A total of 369 E. coli strains [commensal strains and DEC from children with ('DEC-diarrhoea') or without ('DEC-control') diarrhoea] isolated from children aged resistant strains (36 commensals, 33 DEC-control and 85 DEC-diarrhoea) were studied by PCR for the most prevalent resistance mechanisms to ampicillin, trimethoprim/sulfamethoxazole (SXT), tetracycline and chloramphenicol as well as for integrase types 1 and 2. In addition, restriction fragment length polymorphism was performed for SXT-resistant strains. Commensal strains were more frequently resistant to nalidixic acid and ciprofloxacin (68% and 28%, respectively) than DEC strains (23% and 2%, respectively) (Presistant (78%) compared with DEC-control strains (65%) and commensal strains (60%) (Pmechanisms of antibiotic resistance in DEC strains were: for β-lactams, bla(TEM) (31%; 37/118); for SXT, sul2 (48%; 49/103); for tetracycline, tetA (27%; 23/84); and for chloramphenicol, cat (80%; 28/35). The genes sul1 and dfrA1, related to SXT resistance, were more frequent in the DEC-diarrhoea group (41% and 28%, respectively) than in the other two groups (Presistance genes in DEC, including symptomatic strains.

  1. In Vitro Trials of Dittrichia graveolens Essential Oil Combined with Antibiotics.

    Science.gov (United States)

    Miladinović, Dragoljub L; Ilić, Budimir S; Kocić, Branislava D; Marković, Marija S; Miladinović, Ljiljana C

    2016-06-01

    The chemical composition and antibacterial activity of Dittrichia graveolens (L.) Greuter essential oil were examined. Gas chromatography and gas chromatography/mass spectrometry were used to analyze the chemical composition of the essential oil. The antibacterial activity was investigated by the broth microdilution method against thirteen bacterial strains. The interactions of the essential oil and three standard antibiotics: chloramphenicol, tetracycline and streptomycin toward five selected strains were evaluated using the microdilution checkerboard assay in combination with chemometric methods: principal components analysis and hierarchical cluster analysis. Oxygenated monoterpenes were the most abundant compound class in the essential oil (40.6%), with bomyl acetate (21.7%) as the major compound. The essential oil exhibited slight antibacterial activity against the tested bacterial strains in vitro, but the combinations D. graveolens essential oil-chloramphenicol and D. graveolens-tetracycline exhibited mostly synergistic or additive interactions. These combinations reduced the minimum effective dose of the antibiotics and, consequently, minimized their adverse side effects. In contrast, the association of D. graveolens essential oil and streptomycin was characterized by strong antagonistic interactions against E. coli ATCC 25922, S. aureus ATCC 29213 and P. aeruginosa ATCC 27853. In the principal components analysis (PCA) and hierarchical cluster analysis (HCA), streptomycin against these bacterial strains stood out and formed a separate group.

  2. 褥疮的家庭病床治疗体会%Experience of family practice in treating bedsore

    Institute of Scientific and Technical Information of China (English)

    蒋俏兰

    2016-01-01

    目的:探讨褥疮患者的家庭病床治疗措施。方法:采用美宝湿润烧伤膏联合二甲双胍片和/或氯霉素片对褥疮的家庭病床进行治疗。结果:治愈57例,治愈率95%,好转2例,恶化转住院治疗1例。结论:家庭病床采用美宝湿润烧伤膏联合二甲双胍片和/或氯霉素片治疗褥疮效果好,且费用低,适合长期卧床的褥疮患者。%Objective:To explore the treatment measures of family practice in treating bedsore.Methods:Using MEBO combined with metformin and/or chloramphenicol tablets of family practice in the treatment of patients with bedsore.Results:57 cases were cured,and the cure rate was 95%;improved in 2 cases;1 case deteriorated to the hospital for treatment.Conclusion:Family practice using MEBO combined with metformin and/or chloramphenicol tablets has good effect,and the cost is low,which suitable for bedridden patients with bedsore.

  3. Rickettsial ompB promoter regulated expression of GFPuv in transformed Rickettsia montanensis.

    Directory of Open Access Journals (Sweden)

    Gerald D Baldridge

    Full Text Available Rickettsia spp. (Rickettsiales: Rickettsiaceae are Gram-negative, obligate intracellular, alpha-proteobacteria that have historically been associated with blood-feeding arthropods. Certain species cause typhus and spotted fevers in humans, but others are of uncertain pathogenicity or may be strict arthropod endosymbionts. Genetic manipulation of rickettsiae should facilitate a better understanding of their interactions with hosts.We transformed a species never associated with human disease, Rickettsia montanensis, by electroporation with a TN5 transposon (pMOD700 containing green fluorescent protein (GFPuv and chloramphenicol acetyltransferase (CAT genes under regulation of promoters cloned from the Rickettsia rickettsii ompB gene, and isolated a Chloramphenicol-resistant GFP-fluorescent rickettsiae population (Rmontanensis700. The Rmontanensis700 rickettsiae contained a single transposon integrated near an acetyl-CoA acetyltransferase gene in the rickettsial chromosome. Northern blots showed that GFPuv and CAT mRNAs were both expressed as two transcripts of larger and smaller than predicted length. Western immunoblots showed that Rmontanensis700 and E. coli transformed with a plasmid containing the pMOD700 transposon both expressed GFPuv proteins of the predicted molecular weight.Long-standing barriers to transformation of rickettsiae have been overcome by development of transposon-based rickettsial transformation vectors. The ompB promoter may be the most problematic of the four promoters so far employed in those vectors.

  4. A set of vectors for introduction of antibiotic resistance genes by in vitro Cre-mediated recombination

    Directory of Open Access Journals (Sweden)

    Vassetzky Yegor S

    2008-12-01

    Full Text Available Abstract Background Introduction of new antibiotic resistance genes in the plasmids of interest is a frequent task in molecular cloning practice. Classical approaches involving digestion with restriction endonucleases and ligation are time-consuming. Findings We have created a set of insertion vectors (pINS carrying genes that provide resistance to various antibiotics (puromycin, blasticidin and G418 and containing a loxP site. Each vector (pINS-Puro, pINS-Blast or pINS-Neo contains either a chloramphenicol or a kanamycin resistance gene and is unable to replicate in most E. coli strains as it contains a conditional R6Kγ replication origin. Introduction of the antibiotic resistance genes into the vector of interest is achieved by Cre-mediated recombination between the replication-incompetent pINS and a replication-competent target vector. The recombination mix is then transformed into E. coli and selected by the resistance marker (kanamycin or chloramphenicol present in pINS, which allows to recover the recombinant plasmids with 100% efficiency. Conclusion Here we propose a simple strategy that allows to introduce various antibiotic-resistance genes into any plasmid containing a replication origin, an ampicillin resistance gene and a loxP site.

  5. R-plasmid transfer in a wastewater treatment plant.

    Science.gov (United States)

    Mach, P A; Grimes, D J

    1982-12-01

    Enteric bacteria have been examined for their ability to transfer antibiotic resistance in a wastewater treatment plant. Resistant Salmonella enteritidis, Proteus mirabilis, and Escherichia coli were isolated from clinical specimens and primary sewage effluent. Resistance to ampicillin, chloramphenicol, streptomycin, sulfadiazine, and tetracycline was demonstrated by spread plate and tube dilution techniques. Plasmid mediation of resistance was shown by ethidium bromide curing, agarose gel electrophoresis, and direct cell transfer. Each donor was mated with susceptible E. coli and Shigella sonnei. Mating pairs (and recipient controls) were suspended in unchlorinated primary effluent that had been filtered and autoclaved. Suspensions were added to membrane diffusion chambers which were then placed in the primary and secondary setting tanks of the wastewater treatment plant. Resistant recombinants were detected by replica plating nutrient agar master plates onto xylose lysine desoxycholate agar plates that contained per milliliter of medium 10 micrograms of ampicillin, 30 micrograms of chloramphenicol, 10 micrograms of streptomycin, 100 micrograms of sulfadiazine, or 30 micrograms of tetracycline. Mean transfer frequencies for laboratory matings were 2.1 X 10(-3). In situ matings for primary and secondary settling resulted in frequencies of 4.9 X 10(-5) and 7.5 X 10(-5), respectively. These values suggest that a significant level of resistance transfer occurs in wastewater treatment plants in the absence of antibiotics as selective agents.

  6. Evidence that uv-inducible error-prone repair is absent in Haemophilus influenzae Rd, with a discussion of the relation to error-prone repair of alkylating-agent damage

    Energy Technology Data Exchange (ETDEWEB)

    Kimball, R.F.; Boling, M.E.; Perdue, S.W.

    1977-01-01

    Haemophilus influenzae Rd and its derivatives are mutated either not at all or to only a very small extent by ultraviolet (uv) radiation, x rays, methyl methanesulfonate, and nitrogen mustard, though they are readily mutated by such agents as N-methyl-N'-nitro-N-nitrosoguanidine, ethyl methanesulfonate, and nitrosocarbaryl (NC). In these respects H. influenzae Rd resembles the lexA mutants of Escherichia coli that lack the SOS or reclex uv-inducible error-prone repair system. This similarity is further brought out by the observation that chloramphenicol has little or no effect on post-replication repair after uv irradiation. In E. coli, chloramphenicol has been reported to considerably inhibit post-replication repair in the wild type but not in the lexA mutant. Earlier work has suggested that most or all the mutations induced in H. influenzae by NC result from error-prone repair. Combined treatment with NC and either x rays or uv shows that the NC error-prone repair system does not produce mutations from the lesions induced by these radiations even while it is producing them from its own lesions. It is concluded that the NC error-prone repair system or systems and the reclex error-prone system are different.

  7. Microwave Assisted Synthesis, Spectrofluorometric Characterization of Azomethine as Intermediate for Transition Metal Complexes with Biological Application.

    Science.gov (United States)

    Zayed, Mohie E M; Asiri, Abdullah M; Khan, Salman A

    2016-05-01

    Azomethine (1, 5 - Dimethyl - 2 - phenyl -[(3, 4, 5 -trimethoxybenzylidene) amino] -1, 2 - dihydropyrazol - 3 - one) (DTAD) was synthesized by the reaction of 4-aminophenazone with 3,4,5 trimrthoxybenzaldehyd by microwave irradiation. Physicochemical studies such as electronic absorption, molar absorptivity, oscillator strength, dipole moment, florescent quantum yield were investigated in order to explore the analytical potential of azomethine dye. Azomethine go through the solubilization in different micelles and may be used as a probe or quencher to determine the critical micelle concentration (CMC) of SDS and CTAB. It's coordinate to metal salt through the pyrazol-3-one oxygen and the azomethine nitrogen. The structure of ligand and its meal complexes was elucidated by IR, (1)H, (13)C-NMR, EI-MS spectroscopic methods and elemental analysis. The antibacterial activity of these compounds were first tested in vitro by the disc diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration was using chloramphenicol as reference drug. The results showed that compound 1.1 is better inhibitor of both types of tested bacteria as compared to chloramphenicol.

  8. Effects of {gamma}-radiation on the fungus Alternaria alternata in artificially inoculated cereal samples

    Energy Technology Data Exchange (ETDEWEB)

    Braghini, R. [Departamento de Microbiologia, Instituto de Ciencias Biomedicas II, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 1374, CEP 05508-900 Sao Paulo (Brazil)], E-mail: raquelbraghini@yahoo.com.br; Pozzi, C.R. [Instituto de Zootecnia, Rua Heitor Penteado 56, CEP 13460-000, Nova Odessa, Sao Paulo (Brazil); Aquino, S. [Instituto Adolfo Lutz, Av. Dr. Arnaldo, 355 , CEP 01246-902, Sao Paulo (Brazil); Rocha, L.O.; Correa, B. [Departamento de Microbiologia, Instituto de Ciencias Biomedicas II, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 1374, CEP 05508-900 Sao Paulo (Brazil)

    2009-09-15

    The objective of this study was to evaluate the effects of different {gamma}-radiation doses on the growth of Alternaria alternata in artificially inoculated cereal samples. Seeds and grains were divided into four groups: Control Group (not irradiated), and Groups 1, 2 and 3, inoculated with an A. alternata spore suspension (1x10{sup 6} spores/mL) and exposed to 2, 5 and 10 kGy, respectively. Serial dilutions of the samples were prepared and seeded on DRBC (dichloran rose bengal chloramphenicol agar) and DCMA (dichloran chloramphenicol malt extract agar) media, after which the number of colony-forming units per gram was determined in each group. In addition, fungal morphology after irradiation was analyzed by scanning electron microscopy (SEM). The results showed that ionizing radiation at a dose of 5 kGy was effective in reducing the growth of A. alternata. However, a dose of 10 kGy was necessary to inhibit fungal growth completely. SEM made it possible to visualize structural alterations induced by the different {gamma}-radiation doses used.

  9. Optimal Expression Condition of Recombinant RAP

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jie; ZHANG Hong; BI Hao; LIU Zhiguo; GUO Jianli; QU Shen

    2007-01-01

    In order to construct the expression recombinant of human receptor associated protein (RAP), optimize its expression condition and obtain the recombinant protein after expression with high efficiency, two prokaryotic expression vectors-pT7-PL and pET-28a(+) were used to construct the expression recombinant containing RAP cDNA, and the expression efficiency of two kinds of expression E. coli of BL21 strains was compared. The effect of different induction conditions on the expression of recombinant RAP was observed. After recombinant protein was purified with Ni+-nitrilotriacetic acid (Ni+-NTA) affinity chromatogram, its binding ability with microphage was observed. The results showed that two recombinant plasmids both obtained high expression of RAP. The expression levels of RAP in plasmid pT7-PL-RAP in BL21 (DE3, plysS) strain were significantly higher than in BL21 (DE3) strain. The expression of pT7-PL-RAP in the presence of chloramphenicol was higher than in the absence of chloramphenicol, and most of the inducible expressed RAP was soluble. The RAP which was purified by Ni+-NTA resin could strongly bind with the RAW264.7 cells rich in low density lipoprotein receptor (LDLR) family receptors. It was concluded that the expression condition of recombinant RAP was optimized and functional RAP was obtained, which offered a good foundation for the further production of RAP as research tool.

  10. Isolation and identification of zoonotic species of genus arcobacter from chicken viscera obtained from retail distributors of the metropolitan area of San José, Costa Rica.

    Science.gov (United States)

    Villalobos, Edgar García; Jaramillo, Heriberto Fernández; Ulate, Carolina Chaves; Echandi, María Laura Arias

    2013-05-01

    Arcobacter is a genus of growing importance worldwide; some of its species are considered emerging enteropathogens and potential zoonotic agents. In Costa Rica, as well as in other countries, its isolation has been reported, so the objective of this project was to evaluate and identify the presence of Arcobacter in chicken viscera sold in the metropolitan area of San José, Costa Rica, as well as to determine the antimicrobial resistance patterns associated with it. One hundred fifty samples of chicken viscera including heart, liver, and other gastrointestinal organs were purchased from 15 supermarkets and 15 local retailers. De Boer and Houf broths were used as enrichment media; isolation was done with Arcobacter-selective medium and with membrane filtration with blood agar. Typical colonies were identified with genus-specific PCR, and species identification was made with multiplex PCR. Susceptibility to ampicillin, ciprofloxacin, chloramphenicol, erythromycin, gentamicin, and tetracycline was done with the Epsilometer test. The isolation frequency of Arcobacter genus obtained in this study was of 17.3%. A total of 33 isolates were obtained from the poultry samples, and according to the multiplex PCR methodology, 22 (66.7%) isolates were identified as Arcobacter butzleri, 8 (24.2%) as Arcobacter cryaerophilus, and 1 (3.1%) as Arcobacter skirrowii. Two strains were not identified. No statistical significant difference was found when the source of samples was compared. Resistance toward chloramphenicol was 68.75%, followed by ampicillin (43.75%) and ciprofloxacin (18.75%); all strains were susceptible to tetracycline.

  11. Regulation of glutamine synthetase, aspartokinase, and total protein turnover in Klebsiella aerogenes.

    Science.gov (United States)

    Fulks, R M; Stadtman, E R

    1985-12-13

    When suspensions of Klebsiella aerogenes are incubated in a nitrogen-free medium there is a gradual decrease in the levels of acid-precipitable protein and of aspartokinase III (lysine-sensitive) and aspartokinase I (threonine-sensitive) activities. In contrast, the level of glutamine synthetase increases slightly and then remains constant. Under these conditions, the glutamine synthetase and other proteins continue to be synthesized as judged by the incorporation of [14C]leucine into the acid-precipitable protein fraction and into protein precipitated by anti-glutamine synthetase antibodies, by the fact that growth-inhibiting concentrations of chloramphenicol also inhibit the incorporation of [14C]leucine into protein and into protein precipitated by anti-glutamine synthetase antibody, and by the fact that chloramphenicol leads to acceleration in the loss of aspartokinases I and III and promotes a net decrease in the level of glutamine synthetase and its cross-reactive protein. The loss of aspartokinases I and III in cell suspensions is stimulated by glucose and is inhibited by 2,4-dinitrophenol. Glucose also stimulates the loss of aspartokinases and glutamine synthetase in the presence of chloramphenicol. Cell-free extracts of K. aerogenes catalyze rapid inactivation of endogenous glutamine synthetase as well as exogenously added pure glutamine synthetase. This loss of glutamine synthetase is not associated with a loss of protein that cross-reacts with anti-glutamine synthetase antibodies. The inactivation of glutamine synthetase in extracts is not due to adenylylation. It is partially prevented by sulfhydryl reagents, Mn2+, antimycin A, 2,4-dinitrophenol, EDTA, anaerobiosis and by dialysis. Following 18 h dialysis, the capacity of extracts to catalyze inactivation of glutamine synthetase is lost but can be restored by the addition of Fe2+ (or Ni2+) together with ATP (or other nucleoside di- and triphosphates. After 40-60 h dialysis Fe3+ together with NADH (but

  12. Scientific Opinion on the safety and efficacy of Toyocerin® (Bacillus toyonensis as a feed additive for chickens for fattening, weaned piglets, pigs for fattening, sows for reproduction, cattle for fattening and calves for rearing and for rabbits for fattening

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2014-07-01

    Full Text Available Toyocerin® is a feed additive based on a strain originally defined as Bacillus cereus and now re-assigned to Bacillus toyonensis. It was subject to re-evaluation in 2012. Following the publication of the EFSA opinion and the concerns expressed therein regarding the safety of Toyocerin®, the Commission adopted a Regulation which suspended the existing authorisations of the additive. The applicant was given the possibility to submit supplementary data which might allow a re-consideration of the assessment published by EFSA in 2012. The applicant has therefore submitted further data and arguments. B. toyonensis is resistant to chloramphenicol and tetracycline and harbours catQ and tet(M, known acquired resistance genes to these antibiotics. The role of chromosomal genes coding for chloramphenicol acetyl transferase, the major facilitator superfamily transporter and the plasmid-encoded proteins in the gerIC–nucB locus, potentially contributing to or enhancing the observed resistance, has not been established. On the basis of the data provided by the applicant, including the latest submissions, the FEEDAP Panel concludes that B. toyonensis poses a risk for the spread of genes coding for resistance to tetracycline and chloramphenicol, antibiotics of human and veterinary importance. B. toyonensis harbours complete nhe and hbl operons, coding for non-haemolytic and haemolytic enterotoxins, with all genes in the correct orientation, and no insertions, deletions or mutations affecting their transcription, translation or secretion detected. The strain can produce and release cytotoxic agents, but less effectively than the B. cereus group strains selected as positive controls and under the conditions tested. B. toyonensis has the capacity to elaborate functional toxins and thus, to pose a risk to humans exposed to the organism. Toyocerin® has the potential to improve performance of weaned piglets at the minimum recommended dose of 0.5 × 109

  13. TEM-1 AND ROB-1 PRESENCE AND ANTIMICROBIAL RESISTANCE IN HAEMOPHILUS INFLUENZAE STRAINS, ISTANBUL, TURKEY.

    Science.gov (United States)

    Kuvat, Nuray; Nazik, Hasan; Berkiten, Rahmiye; Öngen, Betigül

    2015-03-01

    Resistance of 235 Haemophilus influenzae clinical isolates from Istanbul Medical Faculty Hospital, Turkey were determined against 19 antibiotics by disc diffusion method, and minimum inhibitory concentrations (MICs) of those found resistant to ampicillin, cefuroxim, chloramphenicol and meropenem were measured using E-test. Ampicillin-resistant isolates producing beta-lactamase as demonstrated by a nitrocefin assay were analyzed for the presence of TEM-1 and ROB-1 genes by PCR. Eleven percent of the isolates were resistant to ampicillin (10 µg/ml), of which 73% were beta-lactamase positive and carried TEM-1 gene, but none were positive for ROB-1 gene. All isolates susceptible to amoxicillin-clavulanate (20/10 µg/ml), azithromycin (15 µg/ml), aztreonam (30 µg/ml), cefotaxime (30 µg/ml), ceftriaxone (30 µg/ml), ciprofloxacin (5 µg/ml), levofloxacin (5 µg/ml), and telithromycin (15 µg/ml) but 24%, 15%, 4%, 4%, 2%, 1%, 1%, 0.5%, 0.5% and 0.5% were resistant to trimethoprim-sulfamethoxazole (1.25/23.75 µg/ml), tetracycline (30 µg/ml), cefaclor (30 µg/ml), clarithromycin (15 µg/ml), cefuroxime (30 µg/ml), meropenem (10 µg/ml), chloramphenicol (30 µg/ml), ampicillin-sulbactam (10/10 µg/ml), nalidixic acid (30 µg/ml), and fosfomycin (30 µg/ml), respectively. MIC values of three cefuroxime-resistant isolates was 24, 48 and > 256 µg/ml, respectively; of two meropenem-resistant strains > 256 µg/ml; and of two chloramphenicol-susceptible isolates (by disc diffusion method) 6 µg/ml (considered as intermediate susceptible). Multiple- antibiotics resistance was detected in 15% of the strains, with resistance to 2, 3, 4, 5 and 6 antibiotics in 8.5%, 4%, 2%, 0.5% and 0.5% of the isolates, respectively. By identifying beta-lactamase-negative ampicillin-resistant H. influenzae, empirical therapy with beta-lactam/beta-lactamase inhibitor combinations and second generation cephalosporins would be inappropriate for such patients (approximately 3%). Our findings will

  14. Antimicrobial susceptibility profile, treatment outcome and serotype distribution of clinical isolates of Salmonella enterica subspecies enterica: a 2-year study from Kerala, South India

    Directory of Open Access Journals (Sweden)

    Harichandran D

    2017-03-01

    Full Text Available Deepa Harichandran, Kavitha Radhakrishnan Dinesh Department of Microbiology, Amrita School of Medicine, Amrita Institute of Medical Sciences and Research Centre, Amrita Vishwa Vidyapeetham University, Kochi, Kerala, India Background/purpose: Typhoid and paratyphoid fever continue to be important causes of illness and death in parts of Asia, being associated with poor sanitation and consumption of unsafe food and water. Antimicrobial resistance has emerged to traditional first-line drugs, namely, the fluoroquinolones, as well as to third-generation cephalosporins, posing challenges to treatment. Azithromycin has proven to be an effective alternative for treatment of uncomplicated typhoid fever. The purpose of this study was to determine the antimicrobial susceptibility, clinical outcome and serotype distribution pattern of clinical isolates belonging to Salmonella enterica subspecies enterica. Methodology: All clinical isolates of S. enterica obtained from blood, sterile body fluids, as well as stool and urine samples at Amrita Institute of Medical Sciences and Research Centre, Kerala, India, between August 2011 and July 2013 were included in the study and processed based on standard microbiology protocols. Results: A total of 118 isolates of Salmonella were obtained during the study period. Out of these, 79 were of S. Typhi (66.95%, followed by isolates of S. Paratyphi A (22; 18.64% and S. Typhimurium 12 (10.17%. Five isolates could not be identified further. There was 100% susceptibility to ceftriaxone in all S. enterica subspecies. Ciprofloxacin susceptibility was 32.91% for S. Typhi and 40.90% for S. Paratyphi A as determined by the disk diffusion method. The susceptibility profile of S. Typhi isolates to different antimicrobials was as follows: chloramphenicol (94.93%, ampicillin (77.21%, cotrimoxazole (75.94% and azithromycin (78.48%. For S. Typhi, the minimum inhibitory concentration (MIC of ciprofloxacin required to inhibit the growth

  15. Isolation and characterization of hemolytic bacteria Fish disc and Neon RainbowIsolamento e caracterização de bactérias hemolíticas de Acará Disco e Neon Arco-Íris

    Directory of Open Access Journals (Sweden)

    José Luiz Pedreira Mouriño

    2012-05-01

    Full Text Available The aim of this study was to isolate, identify and determine the ability of potential pathogenic bacteria hemolytic mite Disco (Symphysodon discus and Neon Rainbow (Melanotaenia praecox, and define which of the antibiotic Trimethoprim, Florfenicol, Chloramphenicol, Norfloxacin, Erythromycin, Bacitracin, Enrofloxacin, Tetracycline, and Furazolidone Clindamycin has better inhibitory effect in vitro, and determine the minimum inhibitory concentration (MIC for Chloramphenicol, Norfloxacin, Erythromycin and Enrofloxacin. In an outbreak of ornamental fish deaths were isolated nine strains of Gram negative, hemolytic where 3 were identified, two as Vibrio cholerae and one as Citrobacter braakii. With these strains were performed antibiogram and was determined the minimum inhibitory concentration at two different temperatures (22 and 30 ° C. Antibiotics Enrofloxacin, Norfloxacin, florfenicol, chloramphenicol and trimethoprim showed the best results in vitro inhibition against the Vibrio cholerae, and Citrobacter braakii. The MIC increased in 30 ° C for erythromycin and enrofloxacin against pathogens, while for Florfenicol and norfloxacin the MIC was not influenced by temperature.O objetivo deste estudo foi isolar, identificar e determinar a capacidade hemolítica de possíveis bactérias patogênicas do Acará Disco (Symphysodon discus e Neon Arco-íris (Melanotaenia praecox, e definir qual o antibiótico entre Trimetoprim, Florfenicol, Cloranfenicol, Norfloxacina, Eritromicina, Bacitracina, Enrofloxacina, Tetraciclina, Furazolidona e Clindamicina possui melhor efeito inibitório in vitro, e determinar a concentração inibitória mínima (MIC para Cloranfenicol, Norfloxacina, Eritromicina e Enrofloxacina. Em um surto de mortalidade de peixes ornamentais foram isoladas nove cepas de bactérias Gram negativas, onde três hemolíticas foram identificadas, duas como Vibrio cholerae e uma como Citrobacter braakii. Com estas foram realizados antibiogramas

  16. Antibacterial quality of some antibiotics available in five administrative areas along the national borders of Tanzania

    Directory of Open Access Journals (Sweden)

    Mwambete KD

    2014-12-01

    Full Text Available Kennedy D Mwambete Department of Pharmaceutical Microbiology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania Introduction: In developing countries like Tanzania, bacterial infections are becoming increasingly difficult to treat with available antibiotics. Poor quality antibiotics jeopardize the management of bacterial infections and contribute to the development of antibiotic resistance. Poor storage and harsh tropical climatic conditions accelerate deterioration of antibiotics. Hence, this study investigated the antibacterial effect of antibiotics available in five administrative regions along the national borders of Tanzania. Materials and methods: A cross-sectional study involved the purchase of antibiotics from the Mwanza, Arusha, Kilimanjaro, Mbeya, and Kagera administrative regions. The Kirby–Bauer disk diffusion method was employed to assess antibacterial effects of the antibiotics against Salmonella typhi, Klebsiella spp., Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Inhibition zones (IZ were determined as previously described. Analysis of variance was used to examine the IZ measured using test antibiotics to their respective control antibiotics; differences were considered significant at P<0.05. Results: Seventy-six antibiotic samples from 22 manufacturers were tested. Six antibiotic samples were from anonymous manufacturers and 29 antibiotic samples had no manufacturing or expiration dates. Different samples of the same antibiotics produced variable results. IZ measured using different samples of ampicillin (AMP and ciprofloxacin and their control antibiotics revealed significant differences when tested against S. typhi (P<0.05. Samples of tetracycline and chloramphenicol resulted in IZ comparable to their controls against S. typhi. All samples of AMP yielded comparable IZ on Klebsiella spp., whereas samples of chloramphenicol and tetracycline exerted IZ against P. aeruginosa that

  17. 缘管浒苔游孢子转化系统选择标记的研究%Studies on the Sensitivity of Ulva Linza Spores to Antibiotics

    Institute of Scientific and Technical Information of China (English)

    卢永忠; 杨中飞

    2014-01-01

    选择标记的确定是基因工程研究的一个重要环节。主要研究了缘管浒苔游孢子对青霉素、氯霉素等9种抗生素的敏感性,并与不同发育时期的藻体进行了比较。结果表明:缘管浒苔游孢子对氯霉素、新霉素、红霉素、G-418敏感性较高,在10μg/mL时均有明显的致死效应;不同发育时期浒苔的抗生素敏感性不同,成熟度越高,敏感性越低;对青霉素、卡那霉素、四环素、潮霉素、链霉素不敏感。本实验结果提示氯霉素、红霉素、G-418、新霉素可作为缘管浒苔游孢子转基因研究理想的选择试剂。%To determine the proper screening marker is a key step for genetic engineering. In this study the sensitivity of Ulva linza spores to nine kinds of antibiotics such as penicillin,chloramphenicol and so on was investigated,and it was also compared with Ulva linza in different development period. The results showed that Ulva linza spores were more sensitive to chloramphenicol,erythromycin,neomycin and G -418,all exhibiting obvious killing effects under the concentration of 10μg/mL,whereas mature alga was less sensitive;they were not sensitive to penicillin, kanamycin, homomycin, streptomycin and tetracycline. This indicated that chloramphenicol,erythromycin,neomycin and G-418 could be used as screening agents for gene transferring of Ulva linza spores.

  18. In Vitro Activities of Nisin and Nisin Derivatives Alone and In Combination with Antibiotics against Staphylococcus Biofilms

    Science.gov (United States)

    Field, Des; O’ Connor, Rory; Cotter, Paul D.; Ross, R. Paul; Hill, Colin

    2016-01-01

    The development and spread of pathogenic bacteria that are resistant to the existing catalog of antibiotics is a major public health threat. Biofilms are complex, sessile communities of bacteria embedded in an organic polymer matrix which serve to further enhance antimicrobial resistance. Consequently, novel compounds and innovative methods are urgently required to arrest the proliferation of drug-resistant infections in both nosocomial and community environments. Accordingly, it has been suggested that antimicrobial peptides could be used as novel natural inhibitors that can be used in formulations with synergistically acting antibiotics. Nisin is a member of the lantibiotic family of antimicrobial peptides that exhibit potent antibacterial activity against many Gram-positive bacteria. Recently we have used bioengineering strategies to enhance the activity of nisin against several high profile targets, including multi-drug resistant clinical pathogens such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, staphylococci, and streptococci associated with bovine mastitis. We have also identified nisin derivatives with an enhanced ability to impair biofilm formation and to reduce the density of established biofilms of methicillin resistant S. pseudintermedius. The present study was aimed at evaluating the potential of nisin and nisin derivatives to increase the efficacy of conventional antibiotics and to assess the possibility of killing and/or eradicating biofilm-associated cells of a variety of staphylococcal targets. Growth curve-based comparisons established that combinations of derivatives nisin V + penicillin or nisin I4V + chloramphenicol had an enhanced inhibitory effect against S. aureus SA113 and S. pseudintermedius DSM21284, respectively, compared to the equivalent nisin A + antibiotic combinations or when each antimicrobial was administered alone. Furthermore, the metabolic activity of established biofilms treated with nisin

  19. In vitro activities of nisin and nisin derivatives alone and in combination with antibiotics against Staphylococcus biofilms

    Directory of Open Access Journals (Sweden)

    Des eField

    2016-04-01

    Full Text Available The development and spread of pathogenic bacteria that are resistant to the existing catalogue of antibiotics is a major public health threat. Biofilms are complex, sessile communities of bacteria embedded in an organic polymer matrix which serve to further enhance antimicrobial resistance. Consequently, novel compounds and innovative methods are urgently required to arrest the proliferation of drug-resistant infections in both nosocomial and community environments. Accordingly, it has been suggested that antimicrobial peptides could be used as novel natural inhibitors that can be used in formulations with synergistically-acting antibiotics. Nisin is a member of the lantibiotic family of antimicrobial peptides that exhibit potent antibacterial activity against many Gram-positive bacteria. Recently we have used bioengineering strategies to enhance the activity of nisin against several high profile targets, including multi-drug resistant clinical pathogens such as methicillin-resistant Staphylococcus aureus (MRSA, vancomycin-resistant enterococci (VRE, staphylococci and streptococci associated with bovine mastitis. We have also identified nisin derivatives with an enhanced ability to impair biofilm formation and to reduce the density of established biofilms of methicillin resistant Staphylococcus pseudintermedius (MRSP. The present study was aimed at evaluating the potential of nisin and nisin derivatives to increase the efficacy of conventional antibiotics and to assess the possibility of killing and/or eradicating biofilm-associated cells of a variety of staphylococcal targets. Growth curve-based comparisons established that combinations of derivatives nisin V + penicillin or nisin I4V + chloramphenicol had an enhanced inhibitory effect against S. aureus SA113 and S. pseudintermedius DSM21284 respectively compared to the equivalent nisin A + antibiotic combinations or when each antimicrobial was administered alone. Furthermore, the metabolic

  20. Altered myoelectric activity in the experimental blind loop syndrome.

    Science.gov (United States)

    Justus, P G; Fernandez, A; Martin, J L; King, C E; Toskes, P P; Mathias, J R

    1983-09-01

    Nutrient malabsorption and diarrhea are characteristic of the blind loop syndrome. Alterations in motility have been implicated as a cause of bacterial overgrowth, but the possibility that altered motility may result from alterations in the flora has not been explored. The purpose of this study was to characterize the myoelectric activity of the small intestine in the blind loop rat model. Eight groups of rats were studied: rats with self-filling blind loops, which develop bacterial overgrowth; rats with self-emptying blind loops, which are surgical controls that do not develop overgrowth; unoperated litter mates; rats with self-filling blind loops and unoperated controls treated with chloramphenicol, 200 mg/d i.p.; rats with surgically removed self-filling blind loops; operated control rats; and gnotobiotic rats with self-filling blind loops. In the untreated rats with self-filling blind loops, there was altered myoelectric activity characterized by an increased percentage of slow waves occupied by action potentials and by organized activity similar to the migrating action potential complex. Migrating action potential complex activity and percentage of slow waves occupied by action potentials were significantly decreased with chloramphenicol therapy; that decrease correlated with a decrease in aerobes and anaerobes. Migrating action potential complex activity was abolished in rats with surgically removed self-filling blind loops; they also showed a significant decrease in percentage of slow waves occupied by action potentials. Gnotobiotic rats with self-filling blind loops showed no alteration in myoelectric activity. These data indicate: (a) bacterial overgrowth is associated with a significant increase in percentage of slow waves occupied by action potentials and migrating action potential complex activity; (b) chloramphenicol significantly reduced both percentage of slow waves occupied by action potentials and migrating action potential complex activity; and (c

  1. Clinical pharmacokinetics of antibacterial drugs in neonates.

    Science.gov (United States)

    Paap, C M; Nahata, M C

    1990-10-01

    Neonatal patients are surviving longer due to the rapid advances in medical knowledge and technology. Our understanding of the developmental physiology of both preterm and full term neonates has also increased. It is now apparent that differences in body composition and organ function significantly affect the pharmacokinetics of antibacterial drugs in neonates, and dosage modifications are required to optimise antimicrobial therapy. The penicillins and cephalosporins are frequently used in neonates. Although ampicillin has replaced benzylpenicillin (penicillin G) for empirical treatment of neonatal sepsis, many of the other penicillins may be used in neonates for the management of various infections. Increased volume of distribution (Vd) and decreased total body clearance (CL) affect the disposition of penicillins and cephalosporins. Decreased renal clearance (CLR) due to decreased glomerular filtration and tubular secretion is responsible for the decreased CL for most of the beta-lactams. Aminoglycoside Vd is affected by the increased total body water content and extracellular fluid volume of neonates. The increased Vd, in part, accounts for the extended elimination half-life (t1/2) observed in neonates. Aminoglycoside CL is dependent on renal glomerular filtration which is markedly decreased in neonates, especially those preterm. These drugs appear to be less nephrotoxic and ototoxic in neonates than in older patients, and the role of serum concentration monitoring should be limited to specific neonatal patients. Other antibiotics such as vancomycin, teicoplanin, chloramphenicol, rifampicin, erythromycin, clindamycin, metronidazole and cotrimoxazole (trimethoprim plus sulfamethoxazole) may be used in certain clinical situations. The emergence of staphylococcal resistance to penicillins has increased the need for vancomycin. With the exceptions of vancomycin and chloramphenicol, the efficacy and safety of these other agents in neonates have not been established

  2. Phenotypic and Genetic Characterization ofBacillusSpecies Exhibiting Strong Proteolytic Activity Isolated fromTerasi, An Indonesian Fermented Seafood Product

    Institute of Scientific and Technical Information of China (English)

    Ekachai Chukeatirote; Novi Arfarita; Piyanuch Niamsup; Anittaya Kanghae

    2015-01-01

    In this study, twoBacillistrains namely S2-3 and S4-5, isolated fromTerasi, a traditional fermented seafood product of Indonesia, were studied in terms of their phenotypic and genotypic properties. Both strains are of great interests due to their high proteolytic activity. Initially, they were subjected to morphological determination and a series of biochemical tests. These bacteria were gram-positive, endospore-formingBacilli. Based on 16S rRNA gene sequence analysis, the identities of the strains S2-3 and S4-5 were confirmed asBacillus thuringiensisandB. subtilis, respectively. Additionally, the two strains were also evaluated for their antibiogram profiles. It was found that they were susceptible to chloramphenicol, erythromycin, kanamycin, tetracycline and vancomycin and resistant to ampicillin and intermediately susceptible to bacitracin.

  3. Peptidyl transferase antibiotics perturb the relative positioning of the 3'-terminal adenosine of P/P'-site-bound tRNA and 23S rRNA in the ribosome

    DEFF Research Database (Denmark)

    Kirillov, S V; Porse, B T; Garrett, R A

    1999-01-01

    A range of antibiotic inhibitors that act within the peptidyl transferase center of the ribosome were examined for their capacity to perturb the relative positioning of the 3' end of P/P'-site-bound tRNA and the Escherichia coli ribosome. The 3'-terminal adenosines of deacylated tRNA and N...... decreases, at one or more rRNA sites but, with the exception of chloramphenicol, did not affect cross-linking to the ribosomal proteins. Moreover, the effects were closely similar for both deacylated and N-Ac-Phe-tRNAs, indicating that the drugs selectively perturb the 3' terminus of the tRNA. The strongest......-ribosome complexes. It is concluded that the antibiotics perturb the relative positioning of the 3' end of the P/P'-site-bound tRNA and the peptidyl transferase loop region of 23S rRNA....

  4. Microwave assisted synthesis and antimicrobial activity of some novel pyrimidine derivatives

    Directory of Open Access Journals (Sweden)

    S. J. VAGHASIA

    2007-02-01

    Full Text Available The synthesis of thiazolo [5,4-d]pyrimidines can be achieved from different 5-thiazolidinones, 2-butyl-1H-imidazole-5-carbaldehyde and thiourea using microwave irradiation within 5 min. The structures of the products were supported by FTIR, PMR and mass spectral data. The in vitro antimicrobial activity of the synthesized thiazolo [5,4-d]pyrimidines 1a-j, having substituents at the 1- and 3-positions, were determined by the cup-plate method against several standard strains chosen to define the spectrum and potency of the new compounds. The antimicrobial activities of the thiazolo [5,4-d]pyrimidines 1a-j are compared with those of known chosen standard drugs, viz. ampicillin, chloramphenicol, ciprofloxacin, norfloxacin and griseofulvin.

  5. Assessment of the Occurrence and Risks of Emerging Organic Pollutants (EOPs) in Ikpa River Basin Freshwater Ecosystem, Niger Delta-Nigeria.

    Science.gov (United States)

    Inam, Edu; Offiong, Nnanake-Abasi; Kang, Suil; Yang, Paul; Essien, Joseph

    2015-11-01

    The levels of some emerging organic pollutants (EOPs) including endocrine disrupting compounds, pharmaceuticals and personal care products were quantified in surface water of a freshwater ecosystem, the Ikpa River Basin, Nigeria using liquid chromatography/high resolution tandem mass spectrometry (LC-MS/MS). In addition, leachates and storm water samples collected from nearby dumpsites were also analysed to assess the effect on water quality. Seventeen compounds were detected at the nanogramme-per-litre levels and the ecological risks of selected compounds assessed based on predicted no-effect concentrations derived from comparison of toxicity data recorded for green algae, fish and invertebrate with the maximum measured environmental concentrations, to obtain risk quotients. Some of the compounds showed some level of widespread occurrence or persistence. Also, bisphenol A, chloramphenicol, erythromycin, triclocarban and triclosan were the most important EOPs detected in the study area that may pose detrimental effects to the aquatic organisms based on the outcome of the risk assessment.

  6. Stable transformation of moth bean Vigna aconitifolia via direct gene transfer.

    Science.gov (United States)

    Köhler, F; Golz, C; Eapen, S; Kohn, H; Schieder, O

    1987-07-01

    Direct gene transfer proved to be an efficient transformation method for Vigna aconitifolia, a member of the legume family. Kanamycin resistant calli and plants were regenerated from heat shocked protoplasts treated with PEG and plasmid DNA containing the coding region for aminoglycoside phosphotransferase gene (NPT II). The plant cultivar used was an important factor in attaining higher transformation frequencies. Transformation was confirmed by Southern blot analysis using a non-radioactive detection system. Attempts to transform mesophyll and suspension cultured cells by this method were unsuccessful. Protoplasts electroporated with the plasmid pCAP212, which codes for chloramphenicol acetyltransferase, exhibited transient expression of this gene two days after treatment while electroporated cells did not show this enzyme activity. It is therefore assumed that the DNA uptake is prevented by the cell wall.

  7. The effects of 5-fluorouracil and doxorubicin on expression of human immunodeficiency virus type 1 long terminal repeat

    Energy Technology Data Exchange (ETDEWEB)

    Panozzo, J.; Akan, E. [Argonne National Lab., IL (United States); Griffiths, T.D. [Northern Illinois Univ., De Kalb, IL (United States). Dept. of Biological Sciences; Woloschak, G.E. [Argonne National Lab., IL (United States)

    1996-03-01

    Previous work by many groups has documented induction of the HIV-LTR following exposure of cells to ultraviolet light and other DNA damaging agents. Our experiments set out to determine the relative activation or repression of the HIV-LTR in response to two classes of chemotherapeutic agents: Doxorubicin is a DNA-damage inducing agent, and 5-fluorouracil has an antimetabolic mode of action. Using HeLa cells stably transfected with a construct in which HIV-LTR drives expression of the chloramphenicol acetyl transferase reporter gene, we demonstrated an up to 10-fold induction following doxorubicin treatment in 24 h post-treatment. This induction was repressed by treatment with salicylic acid, suggesting a role for prostaglandin/cyclo-oxygenase pathways and/or NFKB in the inductive response. Induction by 5-fluorouracil, in contrast, was more modest (two-fold at most) though it was consistently elevated over controls.

  8. In vitro sensitivities to antimicrobial drugs of ureaplasmas isolated from the bovine respiratory tract, genital tract and eye.

    Science.gov (United States)

    Kishima, M; Hashimoto, K

    1979-09-01

    The sensitivity to 18 antimicrobial drugs was examined for 66 strains of Ureaplasma sp isolated from respiratory tracts of calves suffering from enzootic pneumonia, urinary tracts of bulls and eyes of cows suffering from infectious bovine kerato-conjunctivitis. Furamizole, tiamulin fumarate, erythromycin lactobionate, malidomycin C, doxycycline hydrochloride, kitasamycin tartrate, tylosin tartrate, T-2636C, tetracycline hydrochloride, oxytetracycline hydrochloride, chlortetracycline hydrochloride, oleandomycin phosphate, furazolidone, spiramycin adipate, chloramphenicol and thiophenicol showed strong inhibiting activity on all the test strains. Among them, furamizole, tiamulin fumarate and erythromycin lactobionate were most active. Kanamycin sulphate showed weak activity on all the strains tested. The differences in origin of the test strains did not affect their sensitivity to any of the drugs.

  9. Susceptibility of Bacteroides nodosus to various antimicrobial agents.

    Science.gov (United States)

    Gradin, J L; Schmitz, J A

    1983-08-15

    The susceptibility of 18 strains of Bacteroides nodosus to 21 antimicrobial agents was tested in vitro. Penicillin was the most effective antibiotic tested. Other antibiotics tested, in order of relative efficacy, were cefamandole, clindamycin, tetracycline, chloramphenicol, erythromycin, sodium cefoxitin, tylosin tartrate, nitrofurazone, tinidazole, and dihydrostreptomycin sulfate. Tests of solutions of 4 antibiotics in 70% ethanol indicated that ethanol served primarily as a diluent and did not contribute substantially to the curative effect of such topical medications on foot rot lesions in sheep. Of the chemicals commonly used in foot baths for treatment of ovine foot rot, copper sulfate was most effective, followed by zinc sulfate, then formalin. Several commercial disinfectants and iodine were quite effective against B nodosus, whereas 5.25% sodium hypochlorite and 70% ethanol alone were relatively ineffective.

  10. Synthesis and Biological Evaluation of Some Novel Dithiocarbamate Derivatives

    Directory of Open Access Journals (Sweden)

    Begüm Nurpelin Sağlık

    2014-01-01

    Full Text Available 18 novel dithiocarbamate derivatives were synthesized in order to investigate their inhibitory potency on acetylcholinesterase enzyme and antimicrobial activity. Structures of the synthesized compounds were elucidated by spectral data and elemental analyses. The synthesized compounds showed low enzyme inhibitory activity. However, they displayed good antimicrobial activity profile. Antibacterial activity of compounds 4a, 4e, and 4p (MIC = 25 μg/mL was equal to that of chloramphenicol against Klebsiella pneumoniae (ATCC 700603 and Escherichia coli (ATCC 35218. Most of the compounds exhibited notable antifungal activity against Candida albicans (ATCC 10231, Candida glabrata (ATCC 90030, Candida krusei (ATCC 6258, and Candida parapsilosis (ATCC 7330. Moreover, compound 4a, which carries piperidin-1-yl substituent and dimethylthiocarbamoyl side chain as variable group, showed twofold better anticandidal effect against all Candida species than reference drug ketoconazole.

  11. [The search for Yersinia enterocolitica in vegetables treated by a cold line in school cafeterias in Montpellier].

    Science.gov (United States)

    Darbas, H; Riviere, M; Oberti, J

    1985-01-01

    From 134 samples of raw or cooked vegetables taken in two points of a cold line we isolated 19 strains of Yersinia enterocolitica, 3 of Y. intermedia 3 of Y. kristensenii. None of them belongs to serotypes usually pathogenic for man. The raw vegetables are most contaminated. Y. kristensenii and Y. intermedia were isolated especially from samples of green salad. The used method was a cold enrichment at 4 degrees C followed by a potassium hydroxyde treatment. The activity of 16 antimicrobial drugs was studied by the disk diffusion test at 28 degrees C. All strains were sensitive to aminoglycosides, minocycline, colistine and cotrimoxazole. The results obtained with chloramphenicol and beta-lactam antibiotics vary in terms of species and/or biotypes.

  12. Enterococcal surface protein Esp does not facilitate intestinal colonization or translocation of Enterococcus faecalis in clindamycin-treated mice.

    Science.gov (United States)

    Pultz, Nicole J; Shankar, Nathan; Baghdayan, Arto S; Donskey, Curtis J

    2005-01-15

    Enterococcal surface protein (Esp) is a cell wall-associated protein of Enterococcus faecalis that has been identified as a potential virulence factor. We used a mouse model to examine whether Esp facilitates intestinal colonization or translocation of E. faecalis to mesenteric lymph nodes. After clindamycin treatment, similar levels of high-density colonization were established after orogastric inoculation of an E. faecalis isolate containing the esp gene within a large pathogenicity island and an isogenic mutant created by allelic replacement of the esp gene with a chloramphenicol resistance cassette (P=0.7); translocation to mesenteric lymph nodes was detected in 3 of 12 (25%) mice in both groups. Isogenic mutants of FA2-2 (a plasmid-free derivative of E. faecalis strain JH2) with or without the esp gene failed to establish colonization of clindamycin-treated mice. These results suggest that Esp does not facilitate intestinal colonization or translocation of E. faecalis.

  13. Antibiotic susceptibility of coagulase-negative staphylococci (CoNS): emergence of teicoplanin-non-susceptible CoNS strains with inducible resistance to vancomycin.

    Science.gov (United States)

    Ma, Xiao Xue; Wang, En Hua; Liu, Yong; Luo, En Jie

    2011-11-01

    Coagulase-negative staphylococci (CoNS) have become increasingly recognized as important agents of nosocomial infection. One of the characteristics of CoNS is their resistance to multiple antimicrobial agents commonly used for the treatment of staphylococcal infections. CoNS strains (n = 745) isolated from a university teaching hospital in China between 2004 and 2009 were tested for antibiotic resistance. The antibiotics were placed into three categories based on resistance levels of the CoNS strains to these antibiotics: high resistance (resistance rate >70 %), including penicillin G, oxacillin and erythromycin; medium resistance (resistance rate between 30 and 70 %), including tetracycline, clindamycin, ciprofloxacin, trimethoprim/sulfamethoxazole and chloramphenicol; and low resistance (resistance rate CoNS is needed to determine their resistance to glycopeptides.

  14. Further data to the aetiology, pathogenesis and therapy of infectious bovine keratoconjunctivitis.

    Science.gov (United States)

    Nagy, A; Vandersmissen, E; Kapp, P

    1989-01-01

    Out of a total of 224 bovine eye secretions, 126 Moraxella bovis and 64 Neisseria ovis strains were isolated. The pathogenesis and histological lesions caused by Neisseria ovis have been studied on the eyes of three calves naturally affected with IBK, using electron microscopy. Neisseria ovis caused in 1-12 weeks old calves acute, transient and mostly benign serous conjunctivitis with only slight affection of the cornea. More rarely erosions and even ulceration of the cornea have been observed. Moraxella bovis and Neisseria ovis strains proved nearly unanimously sensitive in vitro to chloramphenicol, neomycin, oxytetracyclin, nitrofurantoin, erythromycin and cefoperazone. Other antibiotics and chemotherapeutics inhibited the growth of these agents only partly or were ineffective. Experimental therapy has been carried out using a single i.m. injection of Terramycin/LA inj. (Pfizer) in a dose of 20 mg/kg body mass, repeated if necessary after 72-96 h. This formulation proved more effective and practical than treatments used earlier.

  15. Isolation of multiple drug-resistant enteric bacteria from feces of wild Western Lowland Gorilla (Gorilla gorilla gorilla) in Gabon.

    Science.gov (United States)

    Mbehang Nguema, Pierre Philippe; Okubo, Torahiko; Tsuchida, Sayaka; Fujita, Shiho; Yamagiwa, Juichi; Tamura, Yutaka; Ushida, Kazunari

    2015-05-01

    Prevalence of drug-resistant bacteria in wildlife can reveal the actual level of anthropological burden on the wildlife. In this study, we isolated two multiple drug-resistant strains, GG6-2 and GG6-1-1, from 27 fresh feces of wild western lowland gorillas in Moukalaba-Doudou National Park, Gabon. Isolates were identified as Achromobacter xylosoxidans and Providencia sp., respectively. Minimum inhibitory concentrations of the following 12 drugs-ampicillin (ABPC), cefazolin (CEZ), cefotaxime (CTX), streptomycin (SM), gentamicin (GM), kanamycin (KM), tetracycline (TC), nalidixic acid (NA), ciprofloxacin (CPFX), colistin (CL), chloramphenicol (CP) and trimethoprim (TMP)-were determined. Isolate GG6-2 was resistant to all antimicrobials tested and highly resistant to CTX, SM, TC, NA and TMP. Isolate GG6-1-1 was resistant to ABPC, CEZ, TC, CL, CP and TMP.

  16. Antimicrobial susceptibility of listeria monocytogenes from food products

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Knöchel, Susanne; Hasman, Henrik

    2007-01-01

    for susceptibility to ceftiofur, chloramphenicol, ciprofloxacin, erythromycin, florfenicol, penicillin, spectinomycin, streptomycin, tetracycline, tiamulin, trimethoprim, and co-trimoxazole, and the disinfectants benzalkonium chloride and triclosan, by determination of minimum inhibitory concentrations (MICs). All...... isolates were resistant to ceftiofur, but susceptible to the other antibiotics. A single isolate had a MIC of 4 mg/L for ciprofloxacin. For tiamulin. the MIC values were around the breakpoint used. Most isolates had MICs for triclosan at 16 mg/L. The MICs for benzalkonium chloride formed a bimodal...... distribution, with 105 isolates having a MIC of 4 mg/L and 9 isolates MICs of 16 and 32 mg/L. This study showed that Danish isolates of L. monocytogenes have not developed or acquired resistance to antimicrobial agents used for treatment or disinfection, except for benzalkonium chloride. The MICs for triclosan...

  17. The effects of 5'-capping, 3'-polyadenylation and leader composition upon the translation and stability of mRNA in a cell-free extract derived from the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Gerstel, B; Tuite, M F; McCarthy, J E

    1992-08-01

    A new modular expression system was developed to direct the in vitro synthesis of defined transcripts that were used as templates for translation in yeast cell-free extracts. The system was used to examine the influence of 5'-capping, 3'-polyadenylation and leader sequence upon the translation and stability of the synthetic Tn9 cat (chloramphenicol acetyl transferase), yeast PGK (phosphoglycerate kinase) and yeast HSP26 (heat-shock protein 26) mRNAs. The addition of a methylated cap (m7Gppp) or of a poly(A) tail enhanced translation and stabilized the mRNA. The dependence of translation upon capping was reduced in the presence of the HSP26 leader sequence. This may indicate the existence of a translational mechanism that enhances cap-independent translation. The enhancement of the translation and stability of mRNA was relatively insensitive to changes in the position of the poly(A) tail relative to the reading frame.

  18. [Pleuropulmonary localizations of non-typhoid Salmonella infections].

    Science.gov (United States)

    Le Chevalier, B; Jehan, A; Brun, J; Vergnaud, M

    1985-01-01

    Non-typhoid salmonella infections are extremely common, usually taking the form of a benign toxi-infection. In the context of the rare extra-digestive manifestations, the authors report 3 cases of pleuro-pulmonary involvement, in infections due to Salmonella Dublin. In 2 cases, the organism was identified from blood cultures, whilst in the 3rd case it was isolated from pleural fluid. As with other extra-digestive sites, pleuro-pulmonary involvement is favored by underlying pathology, accounting for the grave nature of the problem (amongst the 3 cases, gastrectomy and acute myeloblastic leukemia in one case and obliterative arterial disease in another case). Non-typhoid salmonella infections are sensitive to Sulfamethoxazole-trimethoprim which diffuses well in the respiratory system. They are also sensitive to Amoxicillin and to Chloramphenicol.

  19. The 5' flanking region of a barley B hordein gene controls tissue and developmental specific CAT expression in tobacco plants.

    Science.gov (United States)

    Marris, C; Gallois, P; Copley, J; Kreis, M

    1988-07-01

    The 549 base pairs of the 5' flanking region of a barley seed storage protein (B1 hordein) gene were linked to the reporter gene encoding chloramphenicol acetyl transferase (CAT). The chimaeric gene was transferred into tobacco plants using Agrobacterium tumefaciens. CAT enzyme activity was detected in the seeds, but not in the leaves, of the transgenic plants. Furthermore, enzyme activity was found only in the endosperm, and only from fifteen days after pollination. In contrast, the constitutive 19S promoter from cauliflower mosaic virus (CaMV) directed the expression of the CAT gene in the leaves as well as in both the endosperm and embryo and at all stages in seed development.

  20. Rapid degradation of bensulfuron-methyl upon repeated application in paddy soils

    Institute of Scientific and Technical Information of China (English)

    XIE Xiao-mei; LIU Wei-ping; ABID Subhani

    2004-01-01

    Rapid degradation of bensulfuron-methyl upon repeated application in paddy soils was studied. The results showed that the DT50of bensulfuron-methyl was reduced from 16 d to 9 d in soil with one-year bensulfuron-methyl application. Rapid bensulfuron-methyl degradation was happened to previously untreated soil by addition 5% rapid bensuifuron-methyl adapted soil and was inhibited following pre-treatment with broad-spectrum antibiotic chloramphenicol. In bensulfuron-methyl adapted soil mineralisation of 14C labeled bensulfuronmethyl to 14 CO2 occurred at a faster rate than with previously untreated soil. It was concluded that rapid bensulfuron-methyl degradation upon repeated application is probably linked to the adaptation of soil bacteria which can utilize bensulfuron-methyl as a source of carbon and energy.

  1. Structure of Deinococcus radiodurans tunicamycin-resistance protein (TmrD), a phosphotransferase

    Science.gov (United States)

    Kapp, Ulrike; Macedo, Sofia; Hall, David Richard; Leiros, Ingar; McSweeney, Sean M.; Mitchell, Edward

    2008-01-01

    The open-reading frame (ORF) DR_1419 in the Deinococcus radiodurans genome is annotated as a representative of the wide family of tunicamycin-resistance proteins as identified in a range of bacterial genomes. The D. radiodurans ORF DR_1419 was cloned and expressed; the protein TmrD was crystallized and its X-ray crystal structure was determined to 1.95 Å resolution. The structure was determined using single-wavelength anomalous diffraction with selenomethionine-derivatized protein. The refined structure is the first to be reported for a member of the tunicamycin-resistance family. It reveals strong structural similarity to the family of nucleoside monophosphate kinases and to the chloramphenicol phosphotransferase of Streptomyces venezuelae, suggesting that the mode of action is possibly by phosphorylation of tunicamycin. PMID:18540055

  2. Rescue of Mitomycin C- or Psoralen-Inactivated Micrococcus Radiodurans by Additional Exposure to Radiation or Alkylating Agents

    DEFF Research Database (Denmark)

    Hansen, M. Trier

    1982-01-01

    The processing of damaged DNA was altered in a mitomycin C-sensitive mutant (mtcA) of Micrococcus radiodurans. Even though the mutant retained resistance to 254-nm UV radiation, it did not, in contrast to the wild-type strain, show any excessive DNA degradation or cell death when incubated...... with chloramphenicol after sublethal doses of either UV light or mitomycin C. The results suggest the constitutive synthesis of an enzyme system responsible for wild-type proficiency in the repair of mitomycin C-induced damage. An alternative system able to repair damage caused by mitomycin C was demonstrated...... in the mtcA background. In this strain, additional damage infficted upon the cellular DNA effected a massive rescue of cells previously inactivated by mitomycin C. Rescue was provoked by ionizing radiation, by UV light, or by simple alkylating agents. Cells treated with psoralen plus near-UV radiation could...

  3. Serotypes and Antimicrobial Resistance of Human Nontyphoidal Isolates of Salmonella enterica from Crete, Greece.

    Science.gov (United States)

    Maraki, Sofia; Papadakis, Ioannis S

    2014-01-01

    We report on the serotype distribution and the antimicrobial resistance patterns to 20 different antimicrobials of 150 Salmonella enterica strains isolated from stools of diarrhoeal patients on the island of Crete over the period January 2011-December 2012. Among the S. enterica serotypes recovered, Enteritidis was the most prevalent (37.3%), followed by Typhimurium (28.7%) and Newport (8.7%). No resistance was detected to extended-spectrum cephalosporins and carbapenems. Rates of resistance to ampicillin, amoxicillin/clavulanic acid, chloramphenicol, tetracycline, and cotrimoxazole were 9.3%, 4%, 2%, 15.3%, and 8.7%, respectively. Resistance to ≥4 antibiotics was primarily observed for serotypes Typhimurium and Hadar. Enteritidis remains the predominant serotype in Crete. Although low resistance to most antimicrobials was detected, continued surveillance of susceptibility is needed due to the risk of resistance.

  4. Epstein-Barr virus immediate-early gene product trans-activates gene expression from the human immunodeficiency virus long terminal repeat

    Energy Technology Data Exchange (ETDEWEB)

    Kenney, S.; Kamine, J.; Markovitz, D.; Fenrick, R.; Pagano, J.

    1988-03-01

    Acquired immunodeficiency syndrome patients are frequently coinfected with Epstein-Barr virus (EBV). In this report, the authors demonstrate that an EBV immediate-early gene product, BamHI MLF1, stimulates expression of the bacterial chloramphenicol acetyltransferase (CAT) gene linked to the human immunodeficiency virus (HIV) promoter. The HIV promoter sequences necessary for trans-activation by EBV do not include the tat-responsive sequences. In addition, in contrast to the other herpesvirus trans-activators previously studied, the EBV BamHI MLF1 gene product appears to function in part by a posttranscriptional mechanism, since it increases pHIV-CAT protein activity more than it increases HIV-CAT mRNA. This ability of an EBV gene product to activate HIV gene expression may have biologic consequences in persons coinfected with both viruses.

  5. Genetic engineering of cyanobacteria

    DEFF Research Database (Denmark)

    Jacobsen, Jacob Hedemand

    that allows ligase independent directional cloning of two PCR products in a single step employing the uracilspecific excision reagent (USER) cloning principle. PCR amplified regions of a gene to be inactivated are inserted on either side of an antibiotic resistance cassette marker for positive selection...... of mutant strains.Four antibiotic resistance markers were found to be useful (spectinomycin, gentamicin, chloramphenicol and kanamycin). They were used for generation of both single-locus or double-loci mutants were of Synechococcus sp. PCC 7002. The USER cloning principle was also used in the design....... For that purpose we identified an irreversible two-step biosynthetic pathway from fructose-6-phosphate to mannitol. The pathway, comprised by mannitol-1-phosphate dehydrogenase (mtlD) from Escherichia coli and codon-optimized mannitol-1-phosphatase (mlp) from the protozoan chicken parasite Eimeria tenella...

  6. Prevalence, antimicrobial resistance and risk factors for thermophilic Campylobacter infections in symptomatic and asymptomatic humans in Tanzania

    DEFF Research Database (Denmark)

    Komba, E. V. G.; Mdegela, R. H.; Msoffe, P. L. M.

    2015-01-01

    dilution methods indicated a good correlation, and the tests were in agreement to each other (κ ≥ 0.75). Human illness was found to be associated with young age and consumption of chicken meat and pre-prepared salad. Our data indicate the presence of antibiotic-resistant thermophilic Campylobacter...... sulphate and lowest for ciprofloxacin (22.1%). The rates of resistance for other antibiotics (azithromycin, erythromycin, tetracycline, cephalothin, gentamycin, nalidixic acid, ampicillin, amoxycillin, norfloxacin, chloramphenicol) ranged from 44.1% to 89%. Comparison between disc diffusion and agar...... in humans in the study area. There is a need for routine investigation of the presence of the organisms in gastroenteritis aetiology, including determination of their antibiotic susceptibilities....

  7. Antimicrobial susceptibility and serovars of Salmonella from chickens and humans in Ibadan, Nigeria

    DEFF Research Database (Denmark)

    Fashae, K; Ogunsola, F; Aarestrup, Frank Møller

    2010-01-01

    BACKGROUND: This study determines the prevalence and antibiotic resistance of Salmonella serovars from humans and chickens in Ibadan, Nigeria, in 2004-2007. METHODOLOGY: A total of 991 blood samples were collected from patients in 2004 to 2005 and 641 fecal samples were collected from poultry farms...... in 2007. All Salmonella isolates were serotyped and tested for antimicrobial susceptibility. RESULTS: Thirty-nine (4%) Salmonella isolates were obtained from human blood and 70 (11%) from chicken fecal samples. The human isolates revealed nine different serovars; 82% were non-typhoidal Salmonella and 18......% were (S. Typhi). The majority of serovars from humans were S. Enteritidis (33%), S. Dublin (18%), and S. Typhimurium (18%). Resistance to chloramphenicol, sulfamethoxazole, trimethoprim, and ampicillin ranged from 36% to 59% for the human isolates. Eight different serovars were obtained from chickens...

  8. Anti-enrofloxacin Antibody Production by Using Enrofloxacin-screened HSA as an Immunogen

    Institute of Scientific and Technical Information of China (English)

    LIU Chune; LIN Hong; CAO Limin; JIANG Jie

    2005-01-01

    A two-step zero-length cross-linking procedure using active esters was successfully adopted for conjugating enrofloxacin (EF) to human serum albumin (HSA). The derived conjugate was characterized by UV spectrum and then used for immunization of BALB/C mice. In enzyme-linked immunosorbent assay (ELISA) and competitive inhibition ELISA experiments, the derived antiserum exhibited high antibody titer (greater than 1: 250 000) as well as varied cross-reactivity (from 97.8% to 161.7%) to three analogs of EF belonging to fluoroquinolones family. But over the concentration range studied, no significant cross-reactivity was observed to other group of antibiotics (chloramphenicol, oxytetracycline, sulphamethoxazole and nysfungin). It was confirmed that the synthesized immunogen was highly antigenic and elicited specific antibody responses in BALB/C mice against EF.

  9. Occurrence, seasonal variation and risk assessment of antibiotics in the reservoirs in North China.

    Science.gov (United States)

    Li, Nan; Zhang, Xinbo; Wu, Wei; Zhao, Xinhua

    2014-09-01

    The occurrence and seasonal variability of five groups (tetracycline, quinolone, chloramphenicol, macrolide and sulfonamide) of antibiotics were investigated in the surface water of four reservoirs. The dissolved concentrations of 29 antibiotics were in the ngL(-1) level. Trace levels of all target antibiotics were analyzed using solid-phase extraction followed by liquid chromatography electrospray tandem mass spectrometry. All of the antibiotics were detected at all sampling sites, indicating widespread occurrence of antibiotics in the study area. The detection of florfenicol, josamycin, kitasamycin, spiramycin and sulfameter is the first report of these compounds in reservoir samples. The results showed an association between the presence of some antibiotics at Panjiakou reservoir and cage culture of fish. Twenty-three types of antibiotics showed significant seasonal variations (pantibiotics detected could cause very low risk to algae, daphnid and fish. Further health risk need to be investigated because these reservoirs are drinking water sources.

  10. Shigella sonnei strains isolated from U.S. summer students in Guadalajara, Mexico, from 1986 to 1992.

    Science.gov (United States)

    Scerpella, E G; Mathewson, J J; DuPont, H L; Marani, S K; Ericsson, C D

    1994-10-01

    Plasmid DNA analysis and antibiotic susceptibilities were used to study strains of Shigella sonnei isolated from U.S. travelers to Guadalajara, Mexico, over a period of seven years (1986 to 1992). One hundred sixty-one isolates were analyzed. By the use of cluster analysis, eight different plasmid profiles were identified during this interval. At any point in time, three to seven different plasmid profiles were present in this population. The introduction of strains that carried a new plasmid with a molecular mass of 5.1 MDa was coincidental with an increase in isolation of S. sonnei in 1988. This new plasmid was present in 87.5% of the isolates that were resistant to chloramphenicol. Shigellosis in Guadalajara follows a pattern of hyperendemic transmission with transient peaks of high-frequency isolation of S. sonnei. This pattern results from the concurrent presence of a heterogeneous group of strains as opposed to the widespread transmission of one or a few clones.

  11. Comparative Study of Different Methods for the Prediction of Drug-Polymer Solubility

    DEFF Research Database (Denmark)

    Knopp, Matthias Manne; Tajber, Lidia; Tian, Yiwei;

    2015-01-01

    In this study, a comparison of different methods to predict drug–polymer solubility was carried out on binary systems consisting of five model drugs (paracetamol, chloramphenicol, celecoxib, indomethacin, and felodipine) and polyvinylpyrrolidone/vinyl acetate copolymers (PVP/VA) of different...... monomer weight ratios. The drug–polymer solubility at 25 °C was predicted using the Flory–Huggins model, from data obtained at elevated temperature using thermal analysis methods based on the recrystallization of a supersaturated amorphous solid dispersion and two variations of the melting point...... depression method. These predictions were compared with the solubility in the low molecular weight liquid analogues of the PVP/VA copolymer (N-vinylpyrrolidone and vinyl acetate). The predicted solubilities at 25 °C varied considerably depending on the method used. However, the three thermal analysis methods...

  12. Beta-haemolytic streptococci in acute pharyngitis.

    Science.gov (United States)

    Boukadida, J; Hannechi, N; Boukadida, N; Ben Said, H; Elmherbech, H; Errai, S

    2003-01-01

    To determine the role and importance of beta-haemolytic streptococci in acute pharyngitis and its relative susceptibility to antibiotics, we cultured samples from 143 patients (age range: 3-72 years) who presented over a 5-month period in 2001 at three primary health care centres in Sousse, Tunisia. The cultures yielded 80 beta-haemolytic streptococci (59 group A streptococci and 21 non-group A streptococci). All strains were susceptible to benzylpenicillin, amoxicillin, chloramphenicol, rifampicin and pristinamycin. Susceptibility was variable in erythromycin, tetracycline, fosfomycin, telithromycin and levofloxacin. Minimum inhibitory concentrations were determined by E-test for penicillin, erythromycin and levofloxacin. Our results confirm that penicillin is still the reference treatment for acute pharyngitis. However, to minimize the potential for complications arising from its use, continued vigilance is required.

  13. Appearance and Disappearance of Cyanide-Resistant Respiration in Vigna mungo Cotyledons during and following Germination of the Axis.

    Science.gov (United States)

    Morohashi, Y; Matsushima, H

    1983-09-01

    Mitochondrial preparations isolated from black gram (Vigna mungo L.) cotyledons exhibited cyanide-resistant respiration which was of mitochondrial origin. The appearance and the disappearance of this alternative respiration took place during and following imbibition. During the first 6 hours of imbibition, the respiration was completely inhibited by cyanide, but after this time the alternative respiration markedly developed, reaching a maximal cyanide-resistance 12 to 16 hours after the start of imbibition. Subsequently, the alternative respiration gradually disappeared. The actions of cycloheximide and chloramphenicol indicated that the appearance was dependent on cytoplasmic protein synthesis and that the disappearance depended on both cytoplasmic and mitochondrial protein synthesis. The alternative pathway contributed to state 4 respiration, but not to state 3 respiration, in mitochondria from 1-day-old cotyledons. On day 3, it contributed to neither state 3 nor state 4.

  14. COMPARATIVE ASSESSMENT OF MILK BORNE PATHOGENS AND THEIR ANTIBACTERIAL SENSITIVITY

    Directory of Open Access Journals (Sweden)

    Priyanka Chaudhary et al

    2012-10-01

    Full Text Available Milk is considered as a highly nutritious and valuable human food, consumed by the people in a variety of different products. The present work is an effort to have a survey of number of bacteria present in different milk samples viz., Raw, Boiled, Pasteurized and Skimmed milk collected from local market of Haridwar and its adjoining areas by serial dilution method and the quality of milk assessed by MBRT. The highest mean count was detected in raw milk having 211±0.8 cfu/ml. Among the four types, boiled milk appeared as of best quality. The major microbial contaminants were found to be Bacillus sp, Staphylococcus sp, Streptococcus sp, E. coli and Micrococcus sp. During the present investigation the antibiotic sensitivity test was also performed against all the five genera isolated. It was found that inhibition zone of Chloramphenicol and Ofloxacin was maximum against Streptococcus sp. (24 mm and Staphylococcus sp. (30mm.

  15. Isolation of Salmonella enterica serotype Worthington from a splenic abscess in a patient with chronic myeloid leukemia

    Directory of Open Access Journals (Sweden)

    Ghadage D.P.

    2002-01-01

    Full Text Available Splenic abscesses are caused by Staphylococcus aureus, Streptococcus and bacteria belonging to the family Enterobacteriaceae. We report a case of splenic abscess caused by an unusual serotype of Salmonella. A 55 year old man was admitted with complaints of fever and abdominal pain. On the basis of clinical findings and laboratory reports, a diagnosis of chronic myeloid leukemia was made. Ultrasonography of the abdomen revealed a single large cystic lesion in the spleen. Percutaneous drainage of the abscess was carried out. Salmonella enterica serotype Worthington was isolated from a pus sample taken from the abscess. The isolate was resistant to ampicillin, gentamicin, cefotaxime, chloramphenicol and tetracycline, and sensitive to amikacin and norfloxacin. Serotype Worthington is an emerging pathogen. This is the first report of isolation of this serotype from a splenic abscess. In seriously ill patients, such infections should be treated with a combination of antibiotics to circumvent problems with multidrug resistance.

  16. Febre tifóide: recaída por resistência antimicrobiana. Relato de caso Typhoid fever: relapse due to antimicrobial resistance. Case report

    Directory of Open Access Journals (Sweden)

    Wilson Duarte Alecrim

    2002-12-01

    Full Text Available Relatamos pela primeira vez na Amazônia Brasileira um paciente com febre tifóide, com resistência clínica e laboratorial ao cloranfenicol, droga de escolha para esta doença em nossa região. A recaída foi observada no 7° dia após o término do tratamento e a paciente foi tratada com ciprofloxacina.We report for the first time in the Brazilian Amazon a typhoid fever patient with clinical and laboratorial resistance to chloramphenicol, drug of election for this disease in our region. The relapse was observed at the 7th day after the end of treatment and the patient was treated with ciprofloxacin.

  17. Energetics of cyanophage N-1 multiplication in the diazotrophic cyanobacterium Nostoc muscorum.

    Science.gov (United States)

    Singh, S; Bhatnagar, A; Kashyap, A K

    1994-01-01

    Cyanophage N-1 multiplication was investigated during the latent period of the virus, when 14CO2 fixation was inhibited whereas respiratory O2 uptake increased approximately 67% at 4 h after infection. A simultaneous decrease (70%) in the glycogen content of infected cells indicated its catabolic involvement. A chloramphenicol-sensitive rise in glucose-6-phosphate dehydrogenase activity as a result of N-1 infection partly explained the increase in aerobic respiration. The total ATP pool declined to 53% of the control while Ca(2+)-dependent ATPase activity also declined (25%). In contrast, Mg(2+)-dependent ATPase activity increased (80%) in comparison with uninfected cells. Results suggest that oxidative phosphorylation was more crucial in the control of cyanophage N-1 development than photophosphorylation under photoautotrophic growth conditions.

  18. Identification and Antimicrobial Resistance of Enterococcus Spp. Isolated from the River and Coastal Waters in Northern Iran

    Directory of Open Access Journals (Sweden)

    Majid Alipour

    2014-01-01

    Full Text Available As fecal streptococci commonly inhabit the intestinal tract of humans and warm blooded animals, and daily detection of all pathogenic bacteria in coastal water is not practical, thus these bacteria are used to detect the fecal contamination of water. The present study examined the presence and the antibiotic resistance patterns of Enterococcus spp. isolated from the Babolrud River in Babol and coastal waters in Babolsar. Seventy samples of water were collected in various regions of the Babolrud and coastal waters. Isolated bacteria were identified to the species level using standard biochemical tests and PCR technique. In total, 70 Enterococcus spp. were isolated from the Babolrud River and coastal waters of Babolsar. Enterococcus faecalis (68.6% and Enterococcus faecium (20% were the most prevalent species. Resistance to chloramphenicol, ciprofloxacin, and tetracyclin was prevalent. The presence of resistant Enterococcus spp. in coastal waters may transmit resistant genes to other bacteria; therefore, swimming in such environments is not suitable.

  19. Proteasome Accessory Factor C (pafC) Is a novel gene Involved in Mycobacterium Intrinsic Resistance to broad-spectrum antibiotics--Fluoroquinolones.

    Science.gov (United States)

    Li, Qiming; Xie, Longxiang; Long, Quanxin; Mao, Jinxiao; Li, Hui; Zhou, Mingliang; Xie, Jianping

    2015-07-03

    Antibiotics resistance poses catastrophic threat to global public health. Novel insights into the underlying mechanisms of action will inspire better measures to control drug resistance. Fluoroquinolones are potent and widely prescribed broad-spectrum antibiotics. Bacterial protein degradation pathways represent novel druggable target for the development of new classes of antibiotics. Mycobacteria proteasome accessory factor C (pafC), a component of bacterial proteasome, is involved in fluoroquinolones resistance. PafC deletion mutants are hypersensitive to fluoroquinolones, including moxifloxacin, norfloxacin, ofloxacin, ciprofloxacin, but not to other antibiotics such as isoniazid, rifampicin, spectinomycin, chloramphenicol, capreomycin. This phenotype can be restored by complementation. The pafC mutant is hypersensitive to H2O2 exposure. The iron chelator (bipyridyl) and a hydroxyl radical scavenger (thiourea) can abolish the difference. The finding that pafC is a novel intrinsic selective resistance gene provided new evidence for the bacterial protein degradation pathway as druggable target for the development of new class of antibiotics.

  20. [Estimation of Probiotic Lactobacilli Drug Resistance].

    Science.gov (United States)

    Bruslik, N L; Akhatova, D R; Toimentseva, A A; Abdulkhakov, S R; Ilyinskaya, O N; Yarullina, D R

    2015-01-01

    An actual problem of analysis of probiotic lactobacilli resistance to antibiotics and other drugs used in the treatment of gastro-intestinal disturbances has been for the first time solved. The levels of resistance of 19 strains of Lactobacillus (14 strains of L. fermentum, 4 strains of L.plantarum and 1 strain of L.rhamnosus) isolated from commercial probiotics and sour milk products to 14 antibiotics of various nature, i.e. β-lactams, aminoglycosides, macrolides, clindamycin, vancomycin, rifampicin, ciprofloxacin, tetracycline and chloramphenicol were determined. All the isolates were practically susceptible to the drugs of the first line antihelicobacterial therapy, i.e. amoxicillin and clarithromycin, that makes inexpedient the parallel use of the probiotics containing the above lactobacilli in the treatment of gastritis and gastric ulcer, despite the lactobacilli antagonism with respect to Helicobacter pylory. Lactobacilli are as well resistant to mesalazin and can be used for correction of dysbiosis in inflammatory affections of the intestine.

  1. Bovine mastitis caused by gram negative bacteria in Mosul

    Directory of Open Access Journals (Sweden)

    S. Y. A. Al-Dabbagh

    2012-01-01

    Full Text Available A total of 90 milk samples were collected from cows with clinical and subclinical mastitis from different areas in Mosul city, in a period from October 2009 to June 2010, for the detection of gram negative bacteriological causative agents. The bacteria were identified using morphological, cultural and biochemical characteristics. thirty tow (35.3% gram negative bacterial isolates were obtained from the total count which included 14 isolates (15.5% for Escherichia coli, 7 isolates (7.7% for Klebsiella spp, 4 isolates (4.4% for Pseudomonas aeruginosa, 3 isolates (3.3% for Enterobacter aerogenes ,2 isolates for Serratia marcescens and one isolates (1.1% for each of Aeromonas hydrophila and Pasteurella multocida. Results of antibiotic sensitivity test indicated that most of these isolates were sensitive to Ciprofloxacin following by Gentamycin and Cotrimoxazole, while most of these organisms were resistant to Ampicillin, the isolates showed different percentages of sensitivity to Doxycycline, Tetracycline, Neomycin and Chloramphenicol.

  2. ANTIMICROBIAL ACTIVITY OF MICROORGANISMS AND COLLOIDAL SILVER BASED ON COMPLEX MATERIALS

    Directory of Open Access Journals (Sweden)

    Voitenko O. Yu.

    2014-02-01

    Full Text Available The antimicrobial properties of complex materials containing ultradispersed silver particles directly formed in the Candida albіcans, Escherichia сolі, Pseudomonas fluorescens, and Bacillus cereus cell walls were investigated. Complex material based on pseudomonas was more active against gram-positive bacteria, the yeast like fungi based material was mainly active against colibacillus. After a cell-matrix treatment in a hypertonic solution or by acid hydrolysis, the antimicrobial properties of complex materials increased by 20—40%. In a liquid-phase medium, the complex materials with incorporated silver particles in composition with antibiotics strengthened anti-microbial properties of chloramphenicol, tetracycline and amoxiclav antibiotics with respect to E. faecalis, as well as penicillin antibiotics (ceftriaxone, cefotaxime, amoxicillin, amoxiclav against E. coli. The obtained data can serve as a basis for development of the new antibacterial and fungicide cells based materials impregnated with ultradispersed substances.

  3. Susceptibilidad in vitro de Arcobacter butzleri a seis drogas antimicrobianas In vitro susceptibility of Arcobacter butzleri to six antimicrobial drugs

    Directory of Open Access Journals (Sweden)

    L. Otth

    2004-12-01

    Full Text Available Se determinaron los patrones de susceptibilidad de 50 cepas de A. butzleri mediante el método del E-test. Ninguna cepa fue resistente a gentamicina y tetraciclina, pero, hubo cepas resistentes a eritromicina (2% y ciprofloxacina (2%. Además, el 90 y el 98% de las cepas fueron resistentes a ampicilina y cloramfenicol respectivamente. Solamente dos de las 45 cepas ampicilina-resistentes fueron productoras de ß-lactamasa. Palabras clave: Arcobacter butzleri, susceptibilidad antimicrobiana, bacterias emergentes, E-test, ß-lactamasaThe susceptibility patterns of 50 A. butzleri strains to six antimicrobial agents were determined using the E-test method. No strain was found to be resistant to gentamicin and tetracycline, but two different strains (2% were resistant to erythromycin and ciprofloxacin. Ninety and 98% of the strains were resistant to ampicillin and chloramphenicol, respectively. Only two of the 45 ampicillin resistant strains were able to produce ß-lactamase.

  4. Técnicas analíticas contemporáneas para la identificación de residuos de sulfonamidas, quinolonas y cloranfenicol

    Directory of Open Access Journals (Sweden)

    Y. Verónica Talero-Pérez

    2013-12-01

    Full Text Available The excessive use of drugs in the veterinary industry generates bioaccumulation in animal organs, tissues, muscles and fat. Depending on the concentration, these residues can reach man via the food chain. Food safety comprehends the use of these drugs and their residues such as sulfonamides, chloramphenicol and quinolones, which have been found in different slaughter animals. Some countries have limited regulations to control this issue. The implementation of standards set by the European Union is essential to monitor and control this problem at a national level. In this review, we use analytical techniques to identify the residues produced by these drugs, focusing on recently developed technologies that are essential tools to control this problem. Liquid chromatography combined with mass pectrometry and its various interface systems is the most recommended technology to detect residues in various food matrices.

  5. Comparison of antimicrobial resistance phenotypes and resistance genes in Enterococcus faecalis and Enterococcus faecium from humans in the community, broilers and pigs in Denmark

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Agersø, Yvonne; Gerner-Smidt, P.;

    2000-01-01

    Enterococcus faecalis and E. faecium isolated from humans in the community (98 and 65 isolates), broilers (126 and 122), and pigs (102 and 88) during 1998 were tested for susceptibility to 12 different antimicrobial agents and for the presence of selected genes encoding resistance using PCR...... of the 38 human fecal samples examined using selective enrichment. All vancomycin resistant isolates contained the vanA gene, all chloramphenicol resistant isolates the catpIP501 gene, and all five gentamicin resistant isolates the aac6-aph2 gene. Sixty-one (85%) of 72 erythromycin resistant E. faecalis...... examined and 57 (90%) of 63 erythromycin resistant E. faecium isolates examined contained ermB. Forty (91%) of the kanamycin resistant E. faecalis and 18 (72%) of the kanamycin resistant E. faecium isolates contained aphA3. The tet(M) gene was found in 95% of the tetracycline resistant E. faecalis and E...

  6. Antimicrobial resistance determinant microarray for analysis of multi-drug resistant isolates

    Science.gov (United States)

    Taitt, Chris Rowe; Leski, Tomasz; Stenger, David; Vora, Gary J.; House, Brent; Nicklasson, Matilda; Pimentel, Guillermo; Zurawski, Daniel V.; Kirkup, Benjamin C.; Craft, David; Waterman, Paige E.; Lesho, Emil P.; Bangurae, Umaru; Ansumana, Rashid

    2012-06-01

    The prevalence of multidrug-resistant infections in personnel wounded in Iraq and Afghanistan has made it challenging for physicians to choose effective therapeutics in a timely fashion. To address the challenge of identifying the potential for drug resistance, we have developed the Antimicrobial Resistance Determinant Microarray (ARDM) to provide DNAbased analysis for over 250 resistance genes covering 12 classes of antibiotics. Over 70 drug-resistant bacteria from different geographic regions have been analyzed on ARDM, with significant differences in patterns of resistance identified: genes for resistance to sulfonamides, trimethoprim, chloramphenicol, rifampin, and macrolide-lincosamidesulfonamide drugs were more frequently identified in isolates from sources in Iraq/Afghanistan. Of particular concern was the presence of genes responsible for resistance to many of the last-resort antibiotics used to treat war traumaassociated infections.

  7. Actinomyces pyogenes: susceptibility of 103 clinical animal isolates to 22 antimicrobial agents.

    Science.gov (United States)

    Guérin-Faublée, V; Flandrois, J P; Broye, E; Tupin, F; Richard, Y

    1993-01-01

    Actinomyces pyogenes induces suppurative diseases in ruminants and many other animal species. Most of the earlier antimicrobial susceptibility data has been obtained by disk diffusion techniques. Minimal inhibitory concentrations (MIC) of 22 antibiotics for 103 strains of A pyogenes of animal origin were determined by agar dilution test (Mueller-Hinton agar supplemented with 5% sheep blood). All the strains were susceptible to penicillin G, amoxicillin, methicillin, cephalothin, cefoperazone, pristinamycin, kanamycin, gentamicin, spectinomycin, chloramphenicol, vancomycin, novobiocin and rifampin. Fifty-nine percent were resistant to streptomycin, 67% to tetracycline, doxycycline and minocycline, 12% to erythromycin, spiramycin and lincomycin. Most of the strains resistant to macrolides and lincosamides exhibited a constitutive MLS(B)-like phenotype. In the cultural conditions used, it was not possible to determine accurate MIC of fucidic acid and pefloxacin.

  8. Outbreak of infection caused by Neisseria meningitidis group C type 2 in a nursery.

    Science.gov (United States)

    Sáez-Nieto, J A; Perucha, M; Casamayor, H; Marcen, J J; Llacer, A; Garcia-Barreno, B; Casal, J

    1984-01-01

    An outbreak of meningococcal infection which took place in a nursery in Rioja, Spain, is reported. Between November 1981 and February 1982, 11 patients had meningitis with or without septicaemia. Two died. Three meningococcal strains from the patients isolated were studied. All three were group C type 2 and were resistant to sulphadiazine (MIC 50 mg/l) but susceptible to penicillin, ampicillin, chloramphenicol, rifampicin and spiramycin. This outbreak took place during an epidemic in which serogroup B was the most prevalent in Spain. Two surveys before and after chemoprophylaxis were made to determine the carrier rate in the nursery population. The strain causing the outbreak was found in 2.5 and 4 per cent of persons respectively. Rifampicin was administered to all carriers after the first survey and to carriers of the virulent strain after the second survey. The remaining children were given polysaccharide C vaccine. No more cases arose after this last prophylactic measure.

  9. Antibiotic Susceptibility of Streptococcus Pyogenes Isolated from Respiratory Tract Infections in Dakar, Senegal

    Science.gov (United States)

    Camara, Makhtar; Dieng, Assane; Boye, Cheikh Saad Bouh

    2013-01-01

    Group A Streptococcus (GAS) is one of the major causes of respiratory tract infections. The objectives of this study were to identify isolates of S. pyogenes obtained from respiratory tract infections, and to assess their susceptibility to several antibiotics. A total of 40 strains were isolated and their susceptibility to 17 antibiotics was tested using a standard disk diffusion method. The minimum inhibitory concentrations (MICs) were determined using the E-test. All isolates were sensitive to β-lactam antibiotics including penicillin, amoxicillin, and cephalosporins. Macrolides remain active with the exception of spiramycin, which showed reduced susceptibility. Out of the 40 isolates, 100% of the isolates were resistant to tetracycline. Interestingly, isolates were sensitive to chloramphenicol, teicoplanin, vancomycine, and levofloxacin, providing potential alternative choices of treatment against infections with S. pyogenes. PMID:24826076

  10. Antibacterial properties of some plants used in Mexican traditional medicine for the treatment of gastrointestinal disorders.

    Science.gov (United States)

    Alanís, A D; Calzada, F; Cervantes, J A; Torres, J; Ceballos, G M

    2005-08-22

    Antibacterial properties of aqueous and methanolic extracts of 26 medicinal plants used in Mexico to treat gastrointestinal disorders were tested against eight different species of enteropathogens: two Escherichia coli species; two Shigella sonnei species; two Shigella flexneri species; and two Salmonella sp. species. The results showed that all crude extracts exhibited antibacterial activity, at least against one of the microorganisms tested, at concentrations of 8 mg/mL or lower. The extracts from Caesalpinia pulcherria, Chiranthodendron pentadactylon, Cocos nucifera, Geranium mexicanum (aerial parts and roots), Hippocratea excelsa, and Punica granatum possessed strong antibacterial activity against most of the pathogens tested. In general, methanolic extracts were more active than aqueous extracts. Their activity was higher than chloramphenicol but did not exceed that of trimethoprim. Shigella sonnei species showed the highest susceptibility to both extracts. This is the first evaluation of these plants against bacterial pathogen isolates, which cause diarrhea and dysentery in Mexican population.

  11. Identification and antimicrobial susceptibility patterns of Staphylococcus spp. isolated from canine chronic otitis externa

    Directory of Open Access Journals (Sweden)

    Silva N.

    2001-01-01

    Full Text Available Swab samples obtained from 96 dogs with chronic otitis externa were cultured for the isolation of Staphylococcus species. Of 57 staphylococcal strains, 41 (72% were coagulase-negative (CNS. The identification of staphylococci strains was made by standard procedures for the routine identification of staphylococci in clinical practice. S. sciuri was the most frequent species isolated (22.8% from chronic otitis externa in dogs followed by S. intermedius (12.3%, S. auricularis (10.5% and S. aureus (8.8%. Three (5.2% CNS strains could not be identified. Bacterial isolates were susceptible to enrofloxacin, gentamicin, cephalothin, chloramphenicol and neomycin. Resistance was most common to penicillin G, oxacillin and ampicillin.

  12. Multidrug resistance and ESBL-producing Salmonella spp. isolated from broiler processing plants.

    Science.gov (United States)

    Ziech, Rosangela Estel; Lampugnani, Camila; Perin, Ana Paula; Sereno, Mallu Jagnow; Sfaciotte, Ricardo Antônio Pilegi; Viana, Cibeli; Soares, Vanessa Mendonça; Pinto, José Paes de Almeida Nogueira; Bersot, Luciano dos Santos

    2016-01-01

    The aim of this study was to investigate the occurrence of multidrug-resistant, extended spectrum beta-lactamase (ESBL) producing Salmonella spp. isolated from conveyor belts of broiler cutting rooms in Brazilian broiler processing plants. Ninety-eight strains of Salmonella spp. were analyzed. Multidrug resistance was determined by the disk diffusion test and the susceptibility of the isolated bacteria was evaluated against 18 antimicrobials from seven different classes. The double disk diffusion test was used to evaluate ESBL production. Of the 98 strains tested, 84 were multidrug resistant. The highest rates of resistance were against nalidixic acid (95%), tetracycline (91%), and the beta-lactams: ampicillin and cefachlor (45%), followed by streptomycin and gentamicin with 19% and 15% of strain resistance, respectively. By contrast, 97% of the strains were sensitive to chloramphenicol. 45% of the strains were positive for the presence of ESBL activity. In this study, high rates of multidrug resistance and ESBL production were observed in Salmonella spp.

  13. Clonal Occurrence of Salmonella Weltevreden in Cultured Shrimp in the Mekong Delta, Vietnam.

    Directory of Open Access Journals (Sweden)

    Gazi Md Noor Uddin

    Full Text Available This study investigated the occurrence, serovar and antimicrobial resistance of Salmonella spp. in shrimp samples from intensive and extensive farms located in three different provinces in the Mekong Delta, Vietnam. Shrimp from 11 of the 48 farms all contained S. Weltevreden, except for one farm yielding S. Agona, with no difference in Salmonella occurrence between the two production systems. Pulsed field gel electrophoresis (PFGE of S. Weltevreden showed closely related XbaI pulse types, suggesting a clonal relationship despite the farms and shrimp samples being epidemiologically unrelated. S. Weltevreden was susceptible to most antimicrobials tested, with a few strains being resistant to florfenicol, chloramphenicol, sulfamethoxazole or trimethoprim. Future studies of the ecology of S. Weltevreden should establish if this serovar may survive better and even multiply in warm-water shrimp farm environments compared to other Salmonella serovars.

  14. Population dynamics and antimicrobial susceptibility of Aeromonas spp. along a salinity gradient in an urban estuary in Northeastern Brazil.

    Science.gov (United States)

    Silva, Camila Magalhães; Evangelista-Barreto, Norma Suely; Vieira, Regine Helena Silva Dos Fernandes; Mendonça, Kamila Vieira; de Sousa, Oscarina Viana

    2014-12-15

    The main objective of this study was to quantify population and identify culturable species of Aeromonas in sediment and surface water collected along a salinity gradient in an urban estuary in Northeastern Brazil. Thirty sediment samples and 30 water samples were collected from 3 sampling locations (A, B and C) between October 2007 and April 2008. The Aeromonas count was 10-7050CFU/mL (A), 25-38,500CFU/mL (B) andAeromonas caviae, A. sobria, A. trota, A. salmonicida and A. allosaccharophila) were identified among 41 isolates. All strains were sensitive to chloramphenicol and ceftriaxone, whereas 33 (80, 4%) strains were resistant to at least 2 of the 9 antibiotics tested. Resistance to erythromycin was mostly plasmidial. In conclusion, due to pollution, the Cocó River is contaminated by pathogenic strains of Aeromonas spp. with a high incidence of antibacterial resistance, posing a serious risk to human health.

  15. Antibiogram of bacterial species isolated from canine pyometra

    Directory of Open Access Journals (Sweden)

    Madhu Swamy

    2013-06-01

    Full Text Available Aim: The aim of the present work was to ascertain the bacterial flora causing pyometra in female dogs and their antibiotic sensitivity. Materials and Methods: A study was conducted to determine the antibiogram of bacterial species isolated from 20 female dogs diagnosed with pyometra. The vaginal discharge was collected by sterile swab and streaked smoothly over Mueller Hinton medium and sensitivity towards antibiotics was determined by measuring the zone of inhibition using a Hi-media scale. Results: The antobiogram showed that Gentamicin was the most sensitive (85% antibiotic followed by Enrofloxacin, Ciprofloxacin and Amoxicillin (65%, 65% and 55%, respectively. The isolates were most resistant to Oxytetracycline (85% followed by Tetracycline, Ampicillin, Chloramphenicol, Cloxacillin and Erythromycin (80%, 80%, 75%, 70% and 70%, respectively. Conclusion: Gentamicin was found to be most effective antibiotic against the bacterial species isolated from canine pyometra. [Vet World 2013; 6(8.000: 546-549

  16. Salmonella Enteritidis infection in young broiler chickens from breeding farm: A case report

    Directory of Open Access Journals (Sweden)

    Sri Poernomo

    1997-10-01

    Full Text Available old from a breeding farm not far from Bogor. Samples were examined pathologic anatomically (PA and bacteriologically to isolate the causative agents . The sensitivity of the main causative agents isolated from the samples was tested with some drugs, while its pathogenicity was tested in 3 days old chickens intramuscularly, subcutaneously, intraperitoneally and orally, three chickens per inoculations . Exudative and caseous omphalitis, pericarditis, hepatitis, sirsacculitis, and coxofemoral and knee joints were observed in PA examinations, while on bacteriological examination the main cusative agent, ie. Salmonella Enteritidis was isolated successfully . Drug sensitivity test showed that the pathogen was sensitive to chloramphenicol, baytril, gentamisin, and sulphametoxazole-trimethoprim, and resistant to erythromycin, colistin, streptomycin and kanamycin . On the other hand, pathogenicity test of the isolate showed that all but two chickens which were inoculated orally, were died 24 hours post-inoculation . It was concluded that young broiler chickens of the farm were infected by Salmonella Enteritidis.

  17. Construction of shuttle vectors capable of conjugative transfer from Escherichia coli to nitrogen-fixing filamentous cyanobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Wolk, C.P.; Vonshak, A.; Kehoe, P.; Elhai, J.

    1984-03-01

    Wild-type cyanobacteria of the genus Anabaena are capable of oxygenic photosynthesis, differentiation of cells called heterocysts at semiregular intervals along the cyanobacterial filaments, and aerobic nitrogen fixation by the heterocysts. To foster analysis of the physiological processes characteristic of these cyanobacteria, we have constructed a family of shuttle vectors capable of replication and selection in Escherichia coli and, in unaltered form, in several strains of Anabaena. Highly efficient conjugative transfer of these vectors from E. coli to Anabaena is dependent upon the presence of broad host-range plasmid RP-4 and of helper plasmids. The shuttle vectors contain portions of plasmid pBR322 required for replication and mobilization, with sites for Anabaena restriction enzymes deleted; cyanobacterial replicon pDU1, which lacks such sites; and determinants for resistance to chloramphenicol, streptomycin, neomycin, and erythromycin. 38 references, 7 figures, 1 table.

  18. Cadmium-mediated resistance to metals and antibiotics in a cyanobacterium

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S.P.; Pandey, A.K.

    1982-01-01

    Cadmium-resistant strains of the cyanobacterium Nostoc calcicola were isolated through the step-wise transfer of the organism to higher levels of the metal. One of the Cd-resistant strains (CDsup(r)-10) showed cross-resistance to antibiotics like neomycin (1 ..mu..g/ml), chloramphenicol (3 ..mu..g/ml) but not to streptomycin. The Cd-resistant strain also tolerated elevated levels of metals such as zinc 20 ppm) and mercury (1 ppm). The stability of the metal-resistance required the presence of Cd/sup 2 +/ ions in the growth medium. It is suggested that metal resistance may also be determined by gene(s) on the antibiotic resistance plasmids in cyanobacteria.

  19. Screening of bovine milk samples for sub-clinical mastitis and antibiogram of bacterial isolates

    Directory of Open Access Journals (Sweden)

    Harini H. and Sumathi B.R.

    Full Text Available The study was undertaken to find out the incidence of subclinical mastitis (SCM and to assess the antibiotic sensitivity pattern of the causative organisms in lactating cows in and around Kanakapura taluk, Ramanagara district of Karnataka state. The prevalence of subclinical mastitis was assessed by the results of 3 different screening tests and bacteriological evaluation was done for the milk samples that were found positive. The predominant bacterial isolates recovered were Staphylococcus aureus (58% and Escherichia coli (23.5% followed by Staphylococcus epidermidis (8%, Streptococcus sp. (5.5%, Klebsiella sp. (3% and Bacillus sp. (2%. The in vitro antibiogram studies of bacterial isolates revealed higher sensitivity for ciprofloxacin (89%, ofloxacin (85%, enrofloxacin (82%, gentamicin (80% and chloramphenicol (75%, resistant to colistin, neomycin, streptomycin, penicillin and tetracycline. [Vet. World 2011; 4(8.000: 358-359

  20. Current trend of drug sensitivity in bovine mastitis

    Directory of Open Access Journals (Sweden)

    Rajeev Ranjan

    2010-02-01

    Full Text Available The study was conducted on 190 milk samples of bovine mastitis and 138 samples were confirmed positives for microorganisms. All the 138 samples were subjected to drug sensitivity test. The most effective antibiotic was enrofloxacin (91.67% followed by ciprofloxacin (90.15%, amikacin (87.12%, ceftriaxone (84.10%, chloramphenicol (80.31%, cefotaxime (79.55% and gentamicin (77.27%. Microorganisms were mostly resistant to drugs like streptomycin, penicillinG, ampicillin, cloxacillin, amoxycillin and neomycin in increasing order of resistance. Hence, it is suggested that the line of treatment should be based on antibiogram study of various isolates from bovine mastitis. Further, the selection of drugs after culture and sensitivity test should be based on their ability to cross blood tissue barrier or mammary parenchyma, lipophilicity and ability to work in alkaline pH. [Vet. World 2010; 3(1.000: 17-20

  1. Antimicrobial Activity and Antibiotic Sensitivity of Three Isolates of Lactic Acid Bacteria From Fermented Fish Product, Budu

    Directory of Open Access Journals (Sweden)

    Liasi, S. A.

    2009-01-01

    Full Text Available Three isolates of lactic acid bacteria (LAB from the fermented food product, Budu, were identified as genus lactobacillus (Lactobacillus casei LA17, Lactobacillus plantarum LA22 and L. paracasei LA02, and the highest population was Lb. paracasei LA02. The antibacterial agent produced by the isolates inhibited the growth of a range of gram-positive and gram-negative microorganisms. Antimicrobial sensitivity test to 18 different types of antibiotic were evaluated using the disc diffusion method. Inhibition zone diameter was measured and calculated from the means of five determinations and expressed in terms of resistance or susceptibility. All the LAB isolates were resistant to colestin sulphate, streptomycin, amikacin, norfloxacin, nalidixic acid, mecillinam, sulphanethoxazole/ trimethoprim, kanamycin, neomycin, bacitracin and gentamycin but susceptible to erythromycin, penicillin G, chloramphenicol, tetracycline, ampicillin and nitrofurantion.

  2. Assessment of antifungal effects of copper nanoparticles on the growth of the fungus Saprolegnia sp. on white fish (Rutilus frisii kutum eggs

    Directory of Open Access Journals (Sweden)

    Pegah Kalatehjari

    2015-12-01

    Full Text Available This study was conducted to evaluate the in-vitro effects of copper nanoparticles on the growth of the fungus Saprolegnia sp. isolated from white fish (Rutilus frisii kutum eggs. The antifungal effects were measured by determining the minimum lethal concentration of copper nanoparticles on Saprolegnia sp. in yeast extract glucose chloramphenicol (YGC agar at 25 °C. Saprolegnia grown in YGC agar without added copper nanoparticles served as negative controls. Our study showed that copper nanoparticles at a minimum concentration of 10 ppm have antifungal effects on Saprolegnia sp. The antifungal effects of copper nanoparticles are positively correlated to both concentration and time of exposure. This study showed that the antifungal properties of copper nanoparticles make it a good alternative to malachite green, which is carcinogenic.

  3. Antimicrobial susceptibilities and capsular types of invasive Streptococcus pneumoniae isolated in children in Mexico City.

    Science.gov (United States)

    Echániz-Aviles, G; Velázquez-Meza, M E; Carnalla-Barajas, M N; Soto-Noguerón, A; Solórzano-Santos, F; Pérez Miravete, A; Gatica-Marquina, R; di Fabio, J L

    1997-01-01

    As part of the Sistema Regional de Vacunas (SIREVA) initiative, we conducted a surveillance study to determine the relative prevalence of capsular types of Streptococcus pneumoniae and antimicrobial susceptibility of invasive isolates in children less than 5 years old. We collected 220 isolates and found 33 of the 90 known types, with type 23F as the most common followed by types 6A+B, 14, 19F, and 19A. High penicillin resistance was found in 49 strains (22.2%), 31 belonging to type 23F. Twenty-nine (13.1%) were resistant to erythromycin, 95 (43.1%) were resistant to chloramphenicol, and 24 (10.9%) were resistant to cefotaxime. No strains were resistant to vancomycin.

  4. ISOLATION IPG3-1 AND IPG3-3, ENDOPHYTIC FUNGI FROM DELIMA (PUNICA GRANATUM LINN. TWIGS AND IN VITRO ASSESSMENT OF THEIR ANTI MICROBIAL ACTIVITY

    Directory of Open Access Journals (Sweden)

    Shirly Kumala

    2013-06-01

    Full Text Available IPG3-1,2,3,4,5 were endophytic fungi isolated from Delima twigs via direct seed inoculation on Potato Dextrose Agar (PDA. Macroscopic identification of the isolates showed clearly that IPG3-3 and 4 have radial wrinkles in the centre with black spots while IPG3-5 has flower shape in the middle. The microscopic observation on the other hand, showed that IPG3-1 and 3 has branched septate while IPG3-4 has unbranched septate. Furthermore, IPG3-2 and 5 were branched but septateless. Overall, these endophytes showed no spore formation. Secondary metabolites of IPG3-1 and IPG3-3 endophytic fungi isolates demonstrated stronger inhibition zone percentage against Candida albicans and than towards Staphylococcus aureus and Escherichia coli when campare to their respectively positive control amphotericin B and Chloramphenicol.

  5. An Outbreak of Bartonella bacilliformis in an Endemic Andean Community.

    Directory of Open Access Journals (Sweden)

    Nuria Sanchez Clemente

    Full Text Available Bartonellosis affects small Andean communities in Peru, Colombia and Ecuador. Research in this area has been limited.Retrospective review of 191 cases of bartonellosis managed in Caraz District Hospital, Peru, during the last outbreak (2003.The majority of cases (65% were 14 years old and younger. There was a peak in acute cases after the rainy season; chronic cases presented more constantly throughout the year. The sensitivity of blood smear against blood culture in acute disease was 25%. The most commonly used treatment for chronic disease was rifampicin; chloramphenicol was used to treat most acute cases. Complications arose in 6.8% and there were no deaths.Diagnostic and treatment algorithms for acute and chronic bartonellosis have been developed without a strong evidence base. Preparation of ready-to-go operational research protocols for future outbreaks would strengthen the evidence base for diagnostic and treatment strategies and enhance opportunities for control.

  6. Antimicrobial resistance among Pseudomonas spp. and the Bacillus cereus group isolated from Danish agricultural soil

    DEFF Research Database (Denmark)

    Jensen, Lars Bogø; Baloda, S.; Boye, Mette;

    2001-01-01

    From four Danish pig farms, bacteria of Pseudomonas spp. and the Bacillus cereus group were isolated from soil and susceptibility towards selected antimicrobials was tested. From each farm, soil samples representing soil just before and after spread of animal waste and undisturbed agricultural soil......, when possible, were collected. Soil from a well-characterized Danish farm soil (Hojbakkegaard) was collected for comparison. The Psudomonas spp. and B. cereus were chosen as representative for Gram-negative and Gram-positive indigenous soil bacteria to test the effect of spread of animal waste...... on selection of resistance among soil bacteria. No variations in resistance levels were observed between farms; but when the four differently treated soils were compared, resistance was seen for carbadox, chloramphenicol, nalidixan (nalidixic acid), nitrofurantoin, streptomycin and tetracycline for Pseudomonas...

  7. Bacteriostatic and bactericidal activities of 24 antimicrobial agents against Campylobacter fetus subsp. jejuni.

    Science.gov (United States)

    Vanhoof, R; Gordts, B; Dierickx, R; Coignau, H; Butzler, J P

    1980-07-01

    The bacteriostatic and bactericidal activities of 24 antimicrobial agents were tested with the Dynatech MIC 2000 system against 86 strains of Campylobacter fetus subsp. jejuni from human sources. The penicillins (penicillin G, ampicillin, amoxycillin, carbenicillin) had poor activity. Ampicillin and amoxycillin were equally active. Cefotaxime revealed a rather good activity. Erythromycin, gentamicin, tobramycin, amikacin, and furazolidone were the most active compounds. Two strains (2.3%) were resistant to erythromycin. One strain (1.2%) was completely resistant to tobramycin. The tetracyclines (tetracyline, doxycycline, minocycline) were generally effective, but 8% of the strains were totally resistant to them. Minocycline was the most active. Chloramphenicol, thiamphenicol, and clindamycin had good activity. The bacteriostatic and bactericidal distributions for colistin, nalidixic acid, and metronidazole were broad.

  8. [Comparative susceptibility of Ochrobactrum anthropi, Agrobacterium tumefaciens, Alcaligenes faecalis, Alcaligenes denitrificans subsp. denitrificans, Alcaligenes denitrificans subsp. xylosidans and Bordetella bronchiseptica against 35 antibiotics including 17 beta-lactams].

    Science.gov (United States)

    Bizet, C; Bizet, J

    1995-04-01

    Ochrobactrum anthropi, formerly known as "Achromobacter sp." or CDC group Vd has been isolated from water, hospital environment (antiseptic solutions, dialysis fluids ... ). O. anthropi is a Gram negative, motile, strictly aerobic, oxydase positive and non-fermentative bacteria with a strong urease activity. The susceptibility of 13 strains of O. anthropi was determined by agar diffusion method and compared to those of type strains of Agrobacterium tumefaciens, Alcaligenes faecalis, Alcaligenes denitrificans subsp. denitrificans, Alcaligenes denitrificans subsp. xylosoxydans and Bordetella bronchiseptica. The MICs of 20 antimicrobial agents confirmed the distinct phenotype susceptibility of O. anthropi. All the strains of O. anthropi are sensitive to imipenem, amikacin, gentamicin, netilmicin, nalidixic acid, pefloxacin, ciprofloxacin, tetracyclin, colistin, sulphonamides and rifampicin and resistant to ampicillin, amoxycillin + clavulanic acid, ticarcillin, mezlocillin, cefuroxime, cefamandol, cefoxitin, cefotaxime, cefoperazon, ceftazidime, cefsulodin, aztreonam, streptomycin, kanamycin, pipemidic acid, chloramphenicol, erythromicin, pristinamycin, trimethoprim and fosfomycin. O. anthropi is implicated in nosocomial infections. O. anthropi was the species with the greatest resistance to beta-lactamins.

  9. Identification and antimicrobial resistance of Enterococcus spp. isolated from the river and coastal waters in northern Iran.

    Science.gov (United States)

    Alipour, Majid; Hajiesmaili, Reza; Talebjannat, Maryam; Yahyapour, Yousef

    2014-01-01

    As fecal streptococci commonly inhabit the intestinal tract of humans and warm blooded animals, and daily detection of all pathogenic bacteria in coastal water is not practical, thus these bacteria are used to detect the fecal contamination of water. The present study examined the presence and the antibiotic resistance patterns of Enterococcus spp. isolated from the Babolrud River in Babol and coastal waters in Babolsar. Seventy samples of water were collected in various regions of the Babolrud and coastal waters. Isolated bacteria were identified to the species level using standard biochemical tests and PCR technique. In total, 70 Enterococcus spp. were isolated from the Babolrud River and coastal waters of Babolsar. Enterococcus faecalis (68.6%) and Enterococcus faecium (20%) were the most prevalent species. Resistance to chloramphenicol, ciprofloxacin, and tetracyclin was prevalent. The presence of resistant Enterococcus spp. in coastal waters may transmit resistant genes to other bacteria; therefore, swimming in such environments is not suitable.

  10. [Antibiotic resistance of Shigella strains isolated in Cádiz (author's transl)].

    Science.gov (United States)

    García Martos, P; Marín Casanova, P; García Herruzo, J; Fernández Gutiérrez del Alamo, C

    1980-12-15

    The incidence of shigellosis at the Residencia Sanitaria Fernando Zamacola (Cáciz, Spain) and the antibiotic sensitivity of 94 strains of Shigella sonnei and 40 strains of Shigella flexneri, isolated during the year 1979, has been studied taking into account the present status of strain resistance to the major antibiotics. Three epidemic bouts of shigellosis were detected: one in february by Shigella sonnei (16 cases), and two others in august-september and november due to Shigella flexneri (43 and 29 cases). Children 2 to 5 years old had the highest incidence of Shigella infection. Almost all strains isolated were resistant to the sulphonamides (99.77%). Ampicillin and chloramphenicol had little efficacy against Shigella flexneri (95.00 and 92.50% resistance). The percent resistance of Shigella sonnei strains to phosphomycin was elevated (44.69%). All strains studied were sensitive to colimycin and showed little resistance to the combination trimethoprim-sulfamethoxazol (16.42%).

  11. DISTRIBUTION AND CHARACTERIZATION OF DERMATOPHYTES IN A TERTIARY CARE HOSPITAL IN MADHYAPRADESH

    Directory of Open Access Journals (Sweden)

    Agrawal

    2015-01-01

    Full Text Available Superficial mycosis with dermatophytes has a wide geographical distribution and diverse species prevalence. This mycological study comprised of 204 clinically suspected cases of dermatophytosis. All 204 samples were subjected to direct microscopy by potassium hydroxide (KOH mount and isolation on Sabouraud's dextrose agar containing chloramphenicol without cycloheximide. Culture confirmation was done by tease mount, slide culture and various physiological tests like urease test, hair perforation test etc. In the present study an agar based disk diffusion method was performed to determine the susceptibility of dermatophytes. In this study 49% cases were positive for fungus in microscopy, while 24% was culture positive. The most common clinical types observed was T. cruris (40% followed by T. corporis (34.3%. Young adults in the age group of 21 - 30 years were most commonly affected, belonging to lower middle socio - economic status. Among cultures, T. rubrum was the most common isolate (53% followed by T. mentagrophyte (38.7%.

  12. Chlorine and antibiotic-resistant bacilli isolated from an effluent treatment plant - doi: 10.4025/actascitechnol.v35i1.12951

    Directory of Open Access Journals (Sweden)

    Suzana Cláudia Silveira Martins

    2013-01-01

    Full Text Available Resistance to different concentrations of chlorine and the susceptibility to antibiotics by bacteria isolated from the final effluent of the Pici Campus wastewater treatment plant of the Federal University of Ceará (UFC is evaluated. Twelve strains, morphologically and biochemically identified as belonging to the genus Bacillus, were selected. The strains were submitted to sodium hypochlorite at different contact times and tested against the antibiotics amoxicillin, erythromycin, chloramphenicol, tetracycline, and vancomycin. All strains were resistant to concentration 0.1 ppm chlorine up to 30 minutes, but bacteria resistant to concentrations up to 5,000 ppm for 10 minutes were detected. Bacterial growth was impaired in 10,000 ppm concentration. The strains presented three antibiotic resistance profiles, 50% were sensitive to all antibiotics, 25% were resistant to one antibiotic and 25% were resistant to two antibiotics.  

  13. Antimicrobial drug resistance ofStaphylococcus aureus in dairy products

    Institute of Scientific and Technical Information of China (English)

    Sasidharan S; Prema B; Yoga Latha L

    2011-01-01

    Objective:To evaluate the prevalence of multidrug resistantStaphylococcus aureus(S. aureus) in dairy products.Methods:Isolation and identification ofS. aureus were performed in3 dairy-based food products. The isolates were tested for their susceptibility to5 different common antimicrobial drugs.Results:Of50 samples examined,5 (10%) were contaminated with S. aureus. Subsequently, the5 isolates were subjected to antimicrobial resistance pattern using five antibiotic discs (methicillin, vancomycin, kanamycin, chloramphenicol and tetracycline). Sample 29 showed resistance to methicillin and vancomycin. Sample18 showed intermediate response to tetracycline. The other samples were susceptible to all the antibiotics tested.Conclusions:The results provide preliminary data on sources of food contamination which may act as vehicles for the transmission of antimicrobial-resistantStaphylococcus.Therefore, it enables us to develop preventive strategies to avoid the emergence of new strains of resistantS. aureus.

  14. Isolation and Identification of Vancomycin Resistant Staphylococcus aureus from Post Operative Pus Sample

    Directory of Open Access Journals (Sweden)

    Subhankari Prasad Chakraborty1, Santanu KarMahapatra1, Manjusri Bal2 and Somenath Roy1*

    2011-04-01

    Full Text Available Staphylococcus aureus is most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Recently, S. aureus have evolved resistance to both synthetic and traditional antibiotics. This study was carried out to isolate pathogenic S. aureus from post-operative pus sample, and VRSA was identified by evaluation of resistance patterns using conventional antibiotics. Thirty post operative pus samples were collected from nearby Hospital and species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc gene. Antibiotic susceptibility tests were carried out by MIC, MBC, DAD test and BHI vancomycin screening agar. VRSA were confirmed by PCR amplification of the vanA and vanB genes. From this study, it was observed that isolated S. aureus strains are pathogenic; 30% of strains were resistant to penicillin G, ampicillin and erythromycin; 26.67% strains were resistant to cephotaxime, gentamycin, streptomycin, tetracycline, chloramphenicol, norfloxacin, methicillin and vancomycin.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    Introduction: This study investigated the mechanisms of resistance in 36 E. coli isolated from waste, litter, soil and water samples collected from poultry farms in Southwestern Nigeria. Methodology: Minimum inhibitory concentration (MIC) distributions of the isolates were determined using...... the methods of the Clinical and Laboratory Standard Institute and resistance genes detected by PCR. Results: A total of 30 isolates (94%) showed resistance to more than one antimicrobial. Percentage resistance was: tetracycline 81%, sulphamethoxazole 67%, streptomycin 56%, trimethoprim 47 %, ciprofloxacin 42......%, ampicillin 36%, spectinomycin 28%, nalidixic acid 25%, chloramphenicol 22%, neomycin 14%, gentamicin 8%, amoxicillin-clavulanate, ceftiofur, cefotaxime, colistin, florfenicol and apramycin 0%. Resistance genes found among the isolates include bla-TEM (85%), sul2 (67%), sul3 (17%), aadA (65%), strA (70%), str...

  16. Antibiotic susceptibility of different lactic acid bacteria strains.

    Science.gov (United States)

    Karapetkov, N; Georgieva, R; Rumyan, N; Karaivanova, E

    2011-12-01

    Five lactic acid bacteria (LAB) strains belonging to species Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus delbrueckii subsp. lactis and Streptococcus thermophilus were tested for their susceptibility to 27 antibiotics. The minimum inhibitory concentrations of each antimicrobial were determined using a microdilution test. Among the strains a high susceptibility was detected for most of the cell-wall synthesis inhibitors (penicillins, cefoxitin and vancomycin) and resistance toward inhibitors of DNA synthesis (trimethoprim/sulfonamides and fluoroquinolones). Generally, the Lactobacillus strains were inhibited by antibiotics such as chloramphenicol, erythromycin and tetracycline at breakpoint levels lower or equal to the levels defined by the European Food Safety Authority. Despite the very similar profile of S. thermophilus LC201 to lactobacilli, the detection of resistance toward erythromycin necessitates the performance of additional tests in order to prove the absence of transferable resistance genes.

  17. Investigation of Burkholderia cepacia nosocomial outbreak with high fatality in patients suffering from diseases other than cystic fibrosis.

    Science.gov (United States)

    Shehabi, Asem A; Abu-Al-Soud, Waleed; Mahafzah, Azmi; Khuri-Bulos, Najwa; Abu Khader, Ilham; Ouis, Ibn-Sina; Wadström, Torkel

    2004-01-01

    Over a 1-y period, 26 inpatients at the Jordan University Hospital in Amman were detected with bacteraemia (23 cases) or respiratory tract colonized with B. cepacia (3 cases). A combination of genetic identification and molecular typing has proved that all cases were caused by a single epidemic strain of B. cepacia genomovar IIIa. Nosocomial infections could be documented in 21/26 (81%) patients, mostly with severe underlying or malignant diseases other than cystic fibrosis, but the source of infection was undetected. The overall mortality related to infection with B. cepacia was 42%. All B. cepacia isolates were resistant to ampicillin, amikacin, carbenicillin and gentamicin; and mostly susceptible to piperacillin, chloramphenicol, cotri-moxazole, tetracycline, ceftazidime, and tazocin (62-88%). This study demonstrates the nosocomial and high fatality of B. cepacia genomovar IIIa in Jordanian patients suffering from diseases other than cystic fibrosis.

  18. Opportunistic microorganisms in patients undergoing antibiotic therapy for pulmonary tuberculosis

    Directory of Open Access Journals (Sweden)

    Silvia Maria Rodrigues Querido

    2011-12-01

    Full Text Available Antimicrobial therapy may cause changes in the resident oral microbiota, with the increase of opportunistic pathogens. The aim of this study was to compare the prevalence of Candida, Staphylococcus, Pseudomonas and Enterobacteriaceae in the oral cavity of fifty patients undergoing antibiotic therapy for pulmonary tuberculosis and systemically healthy controls. Oral rinsing and subgingival samples were obtained, plated in Sabouraud dextrose agar with chloramphenicol, mannitol agar and MacConkey agar, and incubated for 48 h at 37ºC. Candida spp. and coagulase-positive staphylococci were identified by phenotypic tests, C. dubliniensis, by multiplex PCR, and coagulase-negative staphylococci, Enterobacteriaceae and Pseudomonas spp., by the API systems. The number of Candida spp. was significantly higher in tuberculosis patients, and C. albicans was the most prevalent specie. No significant differences in the prevalence of other microorganisms were observed. In conclusion, the antimicrobial therapy for pulmonary tuberculosis induced significant increase only in the amounts of Candida spp.

  19. Serotypes and Antimicrobial Resistance of Human Nontyphoidal Isolates of Salmonella enterica from Crete, Greece

    Directory of Open Access Journals (Sweden)

    Sofia Maraki

    2014-01-01

    Full Text Available We report on the serotype distribution and the antimicrobial resistance patterns to 20 different antimicrobials of 150 Salmonella enterica strains isolated from stools of diarrhoeal patients on the island of Crete over the period January 2011-December 2012. Among the S. enterica serotypes recovered, Enteritidis was the most prevalent (37.3%, followed by Typhimurium (28.7% and Newport (8.7%. No resistance was detected to extended-spectrum cephalosporins and carbapenems. Rates of resistance to ampicillin, amoxicillin/clavulanic acid, chloramphenicol, tetracycline, and cotrimoxazole were 9.3%, 4%, 2%, 15.3%, and 8.7%, respectively. Resistance to ≥4 antibiotics was primarily observed for serotypes Typhimurium and Hadar. Enteritidis remains the predominant serotype in Crete. Although low resistance to most antimicrobials was detected, continued surveillance of susceptibility is needed due to the risk of resistance.

  20. Imaging in plague. Case report

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, A.J.; Rodriguez, A.A.; Turnbull, G.L.; Reeves, T.A.

    1987-09-01

    An 8-year-old boy presented with elevated temperature, malaise, hepatosplenomegaly, mesenteric adenitis, and septic shock. Cultures of biopsied abdominal lymph nodes as well as the blood grew Yersinia pestes. The boy's condition improved after two weeks of chloramphenicol and cefotaxime (Claforan). Two days after stopping intravenous antibiotic therapy, the patient again became febrile and complained of abdominal pain. Abdominal imaging with /sup III/In labeled leukocytes did not show any abnormalities, however, /sup 67/Ge-citrate scintigraphy demonstrated an abnormal focus of increased radiopharmaceutical uptake within a confluence of necrosed lymph nodes with the right upper quadrant of the abdomen. In addition, abnormal /sup 67/Ga uptake was seen within the left hip region. Correlative imaging with computed tomography is also presented.

  1. Plasmid-mediated extended-spectrum beta-lactamase-producing strains of Enterobacteriaceae isolated from diabetes foot infections in a Brazilian diabetic center

    Directory of Open Access Journals (Sweden)

    R.N. Motta

    2003-04-01

    Full Text Available We bacteriologically analyzed 156 species of Enterobacteriaceae, isolated from 138 patients with community-acquired diabetic foot ulcers, in a prospective study made at a diabetic center and at the Federal University of Ceará, Brazil, from March, 2000, to November, 2001.The samples were cultured using selective media, and identification, susceptibility tests and detection of plasmid-mediated-extended-spectrum-beta-lactamase (ESBL producing strains were made with conventional and automated methods. The most frequently occurring pathogens were K. pneumoniae (21.2%, Morganella morganii (19.9% and E. coli (15.4%. High resistance rates were noted for ampicillin, first generation cephalosporin, trimethoprim/sulfamethoxazole, tetracycline, amoxicillin-clavulanic acid and chloramphenicol. ESBL-producing strains were detected in 6% of the patients. Resistance among gram-negative bacteria has become increasingly common, even in community-acquired infections.

  2. Genetic transformation of marine cyanobacterium Synechococcus sp.CC9311 (Cyanophyceae) by electroporation

    Institute of Scientific and Technical Information of China (English)

    CHEN Huaxin; LIN Hanzhi; JIANG Peng; LI Fuchao; QIN Song

    2013-01-01

    Synechococcus sp.CC9311 is a marine cyanobacterium characterized by type V chromatic acclimation (CA).A genetic transformation system was developed as a first step to elucidate the molecular mechanism of CA.The results show that Synechococcus sp.CC9311 cells were sensitive to four commonly used antibiotics:ampicillin,kanamycin,spectinomycin,and chloramphenicol.An integrative plasmid to disrupt the putative phycoerythrin lyase gene mpeV,using a kanamycin resistance gene as selectable marker,was constructed by recombinant polymerase chain reaction.The plasmid was then transformed into Synechococcus sp.CC9311 via electroporation.High transformation efficiency was achieved at a field strength of 2 kV/cm.DNA analysis showed that rpe V was fully disrupted following challenge of the transformants with a high concentration of kanamycin.In addition,the transformants that displayed poor growth on agar SN medium could be successfully plated on agarose SN medium.

  3. Studies on the pathogenic bacterium of ulcer disease in Epinephelus awoara

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Studies were conducted to determine the cause of the acute mortality of cage-cultured Epinephelus awoara in the Tong'an Bay of Xiamen, China during the summer of 2002. Predominant bacteria strain TS-628 was isolated from the diseased grouper. The virulence test confirmed that TS-628 was the pathogenic bacterium. Biochemical characteristics of the isolates were determined using the automatic bacterial identification system and standard tube tests. To further confirm the identification, a 1 121 bp 16S rRNA gene sequence of the isolate was amplified by PCR, which had been deposited into Genbank (accession number: AY747308). According to the biochemical characteristics and by comparing the 16S rRNA gene homology of the isolate, the pathogenic bacterium was identified as Vibrio harveyi. Drug sensitivity tests showed that this pathogenic bacterium was sensitive to 16 antibacterials, especially to chloramphenicol and actinospectacin, but completely resistant to antibacterials likes vancomycin, penicillin, lincomycin, and so on.

  4. Toxicity of cylindrospermopsin to the brine shrimp Artemia salina: comparisons with protein synthesis inhibitors and microcystins.

    Science.gov (United States)

    Metcalf, J S; Lindsay, J; Beattie, K A; Birmingham, S; Saker, M L; Törökné, A K; Codd, G A

    2002-08-01

    The Artemia salina bioassay was successfully applied to the analysis of the hepatotoxic cyanobacterial alkaloid and protein synthesis inhibitor, cylindrospermopsin. A dose-dependent response in mortality was observed for purified cylindrospermopsin and LC(50) values decreased with time from 8.1 to 0.71 microg/ml(-1), between 24 and 72 h, respectively. Cylindrospermopsin was slightly less potent than micro cystin-LR, with similar LC(50) values on a gravimetric basis, but was more toxic to A.salina than the protein synthesis inhibitors, cycloheximide, chloramphenicol and tetracycline. Cylindrospermopsin-containing strains of the cyanobacterium Cylindrospermopsis raciborskii were found to be toxic to A.salina and the LC(50) concentration for these strains over time was greater than the LC(50) for purified cylindrospermopsin, with the exception of C. raciborskii strain CR1.

  5. Topical antibiotics in the management of corneal ulcer

    Directory of Open Access Journals (Sweden)

    Reddy P

    1988-01-01

    Full Text Available A total of 82 patients suffering from corneal ulcer were treated with framycetin 0.5%, gentamicin 3 mg./ml, chloramphenicol 0.4% and a neomycin combination containing Polymixin B sulphate 5000 u, neomycin sulphate 1700 u and gramicidin 0.025 mg/mL in a Randomised comparative study. The commonest organism isolated was Staphylococcus followed by Pneumococcus, Streptococcus and Pseudomonas. The in vitro sensitivity of these isolates to framycetin was higher than that to others Framycetin produced both earlier and a greater degree of improvement in mean score of signs and symptoms than the other antibiotics. It can thus be concluded that framycetin has a better profile of antibacterial activity and clinical efficacy than some other commonly used topical antibiotics in the treatment of corneal ulcer.

  6. Determinação simultânea de resíduos de cloranfenicol, tianfenicol e florfenicol em leite bovino por cromatografia eletrocinética micelar

    Directory of Open Access Journals (Sweden)

    Leonardo Pezza

    2006-10-01

    Full Text Available A micellar electrokinetic chromatographic method (MEKC is described for determining residues of amphenicols(chloramphenicol,thiamphenicol and florfenicol in bovine milk. MEKC is conducted by using a separation buffer consisting of 20 mM Na2HPO4, 10 mM Na2B4O7, 50 mM SDS at pH 8.0; UV detection at 210 nm and 10 kV of voltage. The limit of detection ranged from 4.3-5.3 µg L-1. The MEKC method was applied for the simultaneous determination of amphenicols in milk samples spiked with amphenicols at three concentration levels: 10, 30 and 50 µg L-1. Recoveries ranging from 91-105% were obtained by following a simple extraction/preconcentration procedure.

  7. Molecular Characterization of Staphylococcus aureus Isolates Transmitted between Patients with Buruli Ulcer.

    Directory of Open Access Journals (Sweden)

    Nana Ama Amissah

    Full Text Available Buruli ulcer (BU is a skin infection caused by Mycobacterium ulcerans. The wounds of most BU patients are colonized with different microorganisms, including Staphylococcus aureus.This study investigated possible patient-to-patient transmission events of S. aureus during wound care in a health care center. S. aureus isolates from different BU patients with overlapping visits to the clinic were whole-genome sequenced and analyzed by a gene-by-gene approach using SeqSphere(+ software. In addition, sequence data were screened for the presence of genes that conferred antibiotic resistance.SeqSphere(+ analysis of whole-genome sequence data confirmed transmission of methicillin resistant S. aureus (MRSA and methicillin susceptible S. aureus among patients that took place during wound care. Interestingly, our sequence data show that the investigated MRSA isolates carry a novel allele of the fexB gene conferring chloramphenicol resistance, which had thus far not been observed in S. aureus.

  8. Genetic transformation of marine cyanobacterium Synechococcus sp. CC9311 (Cyanophyceae) by electroporation

    Science.gov (United States)

    Chen, Huaxin; Lin, Hanzhi; Jiang, Peng; Li, Fuchao; Qin, Song

    2013-03-01

    Synechococcus sp. CC9311 is a marine cyanobacterium characterized by type IV chromatic acclimation (CA). A genetic transformation system was developed as a first step to elucidate the molecular mechanism of CA. The results show that Synechococcus sp. CC9311 cells were sensitive to four commonly used antibiotics: ampicillin, kanamycin, spectinomycin, and chloramphenicol. An integrative plasmid to disrupt the putative phycoerythrin lyase gene mpeV, using a kanamycin resistance gene as selectable marker, was constructed by recombinant polymerase chain reaction. The plasmid was then transformed into Synechococcus sp. CC9311 via electroporation. High transformation efficiency was achieved at a field strength of 2 kV/cm. DNA analysis showed that mpeV was fully disrupted following challenge of the transformants with a high concentration of kanamycin. In addition, the transformants that displayed poor growth on agar SN medium could be successfully plated on agarose SN medium.

  9. Avocado fruit protoplasts: a cellular model system for ripening studies.

    Science.gov (United States)

    Percival, F W; Cass, L G; Bozak, K R; Christoffersen, R E

    1991-12-01

    Mesocarp protoplasts were isolated from mature avocado fruits (Persea americana cv. Hass) at varying stages of propylene-induced ripening. Qualitative changes in the pattern of radiolabel incorporation into polypeptides were observed in cells derived from fruit at the different stages. Many of these differences correlate with those observed during radiolabeling of polypeptides from fresh tissue slices prepared from unripe and ripe fruit. Protoplasts isolated from fruit treated with propylene for one day or more were shown to synthesize cellulase (endo-ß-1,4-glucanase) antigen, similar to the intact propylene-treated fruit. These results suggest that the isolated protoplasts retain at least some biochemical characteristics of the parent tissue. The cells may also be used in transient gene expression assays. Protoplasts isolated from preclimacteric and climacteric fruit were equally competent in expressing a chimeric test gene, composed of the CaMV 35S RNA promoter fused to the bacterial chloramphenicol acetyltransferase gene, which was introduced by electroporation.

  10. Antimicrobial susceptibility of Streptococcus pneumoniae and genotypic characterization of erythromycin-resistant strains in Porto Alegre, Brazil

    Directory of Open Access Journals (Sweden)

    F. T. Weber

    2010-03-01

    Full Text Available The antimicrobial susceptibility of 64 strains of S. pneumoniae obtained from three hospitals in Porto Alegre, Brazil, isolated between 2004 and 2005, was determined, using the agar-dilution method. The prevalence of resistant (intermediate and full resistance strains to trimethoprim/sulphamethoxazole, penicillin, tetracycline, erythromycin, chloramphenicol, and ceftriaxone were 68%, 28%, 18%, 15%, 3%, and 1%, respectively. All strains were susceptible to vancomycin. Among 18 penicillin-resistant strains, 7 were resistant to at least two other antimicrobial drugs. All erythromycin-resistant strains, except one, contained the erm(B and/or mef(A/E genes, with a predominance of the former. The resistance rate to penicillin and erythromycin in Porto Alegre remained stable. The combination of trimethoprim/ sulphamethoxazole should not be recommended to treat pneumococcal infections, because of the high rate of resistant strains.

  11. ASSESSMENT OF ANTIMICROBIAL AND CYTOTOXIC ACTIVITIES OF ETHANOLIC EXTRACT OF LEAVES OF ACALYPHA HISPIDA

    Directory of Open Access Journals (Sweden)

    B. Bokshi*, M.A.S. Sayeed, M.I. Ahmed, U.K. Karmakar, S.K. Sadhu

    2012-06-01

    Full Text Available The ethanolic extract of leaves of Acalypha hispida was evaluated for phytochemical, cytotoxic and antibacterial activities. Phytochemical studies revealed the presence of flavonoids, saponins, glycosides, reducing sugars and steroids. Cytotoxic activity was investigated by brine shrimp (Artemia salina lethality assay. The extract showed potent cytotoxic effect (LC50 19.95µg/ml which is comparable to standard cytotoxic drug chloramphenicol (LC50 7µg/ml. Antibacterial activity was tested by disk diffusion method. The extract exhibited significant antibacterial activity against Salmonella typhe and moderate activity against Enterococcus coli, Streptococcus saprophyticus and Streptococcus agalactin whereas Shigella dysentery found resistant at 250µg/disc and 500µg/disc.

  12. A comparison of the efficacy of doramectin, closantel and levamisole in the treatment of the 'oriental eye fluke', Philophthalmus gralli, in commercially reared ostriches (Struthio camelus : short communication

    Directory of Open Access Journals (Sweden)

    S. Mukaratirwa

    2008-05-01

    Full Text Available Commercially reared ostriches at Msengi farm situated in the Chinhoyi area of Mashonaland West province in Zimbabwe were found to be infected with the 'oriental eye fluke', Philopthalmus gralli, in 2001. This was the 1st record of the fluke in Zimbabwe. Trials were conducted to identify a suitable drug for the treatment of this fluke. A total of 12 ostriches confirmed to be infected with the fluke through clinical examination of the eyes and identification of the fluke were randomly divided into 3 equal groups, with each group receiving a different treatment protocol. The 3 drugs used were doramectin, levamisole and closantel. Each of the drugs was used in combination with chloramphenicol as an eye ointment. Levamisole was administered topically into the eye whereas doramectin and closantel were administered parenterally as an intramuscular injection. The results indicated a positive response in levamisole-treated birds but there were no noticeable responses to doramectin and closantel treatments.

  13. Gene Cloning of Penicillin V Acylase from Bacillus sp BAC4 by Genomic Library

    Directory of Open Access Journals (Sweden)

    ELFI SUSANTI VH

    2004-01-01

    Full Text Available This research was aimed to clone and identify penicillin V acylase (PVA gene of Bacillus sp. BAC4 by genomic library. Chromosome DNA of Bacillus sp. BAC4 was isolated by Wang method. pHB201 of E. coli was isolated by alkali lyses method. Recombinant DNA of Bacillus sp. BAC4 chromosome fragment and pHB201 was made by ligase process using T4 DNA ligase. Transformation of E. coli using this recombinant plasmid was carried out according to Mandel-Higa method. The results indicated that chromosome DNA fragment of Bacillus sp. BAC4 was bigger 23 kb with purity 1,3. Plasmid DNA fragment of E coli was 6,5 kb. Transformants laboring pHB201 recombinant plasmid was screen as blue-white colonies in a medium containing IPTG/X-gal and chloramphenicol.

  14. Topoisomerase activity during the heat shock response in Escherichia coli K-12.

    Science.gov (United States)

    Camacho-Carranza, R; Membrillo-Hernández, J; Ramírez-Santos, J; Castro-Dorantes, J; Chagoya de Sánchez, V; Gómez-Eichelmann, M C

    1995-01-01

    During the upshift of temperature from 30 to 42, 45, 47, or 50 degrees C, an increase in the level of supercoiling of a reporter plasmid was observed. This increase was present in groE and dnaK mutants but was inhibited in cells treated with chloramphenicol and novobiocin. The intracellular [ATP]/[ADP] ratio increased rapidly after an upshift in temperature from 30 to 47 degrees C and then decreased to reach a level above that observed at 30 degrees C. These results suggest that gyrase and proteins synthesized during heat shock are responsible for the changes seen in plasmid supercoiling. Proteins GroE and DnaK are probably not involved in this phenomenon. PMID:7768879

  15. Antibiotic Resistant Salmonella and Vibrio Associated with Farmed Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Sanjoy Banerjee

    2012-01-01

    Full Text Available Salmonella and Vibrio species were isolated and identified from Litopenaeus vannamei cultured in shrimp farms. Shrimp samples showed occurrence of 3.3% of Salmonella and 48.3% of Vibrio. The isolates were also screened for antibiotic resistance to oxolinic acid, sulphonamides, tetracycline, sulfamethoxazole/trimethoprim, norfloxacin, ampicillin, doxycycline hydrochloride, erythromycin, chloramphenicol, and nitrofurantoin. Salmonella enterica serovar Corvallis isolated from shrimp showed individual and multiple antibiotic resistance patterns. Five Vibrio species having individual and multiple antibiotic resistance were also identified. They were Vibrio cholerae (18.3%, V. mimicus (16.7%, V. parahaemolyticus (10%, V. vulnificus (6.7%, and V. alginolyticus (1.7%. Farm owners should be concerned about the presence of these pathogenic bacteria which also contributes to human health risk and should adopt best management practices for responsible aquaculture to ensure the quality of shrimp.

  16. Antibiotic resistant Salmonella and Vibrio associated with farmed Litopenaeus vannamei.

    Science.gov (United States)

    Banerjee, Sanjoy; Ooi, Mei Chen; Shariff, Mohamed; Khatoon, Helena

    2012-01-01

    Salmonella and Vibrio species were isolated and identified from Litopenaeus vannamei cultured in shrimp farms. Shrimp samples showed occurrence of 3.3% of Salmonella and 48.3% of Vibrio. The isolates were also screened for antibiotic resistance to oxolinic acid, sulphonamides, tetracycline, sulfamethoxazole/trimethoprim, norfloxacin, ampicillin, doxycycline hydrochloride, erythromycin, chloramphenicol, and nitrofurantoin. Salmonella enterica serovar Corvallis isolated from shrimp showed individual and multiple antibiotic resistance patterns. Five Vibrio species having individual and multiple antibiotic resistance were also identified. They were Vibrio cholerae (18.3%), V. mimicus (16.7%), V. parahaemolyticus (10%), V. vulnificus (6.7%), and V. alginolyticus (1.7%). Farm owners should be concerned about the presence of these pathogenic bacteria which also contributes to human health risk and should adopt best management practices for responsible aquaculture to ensure the quality of shrimp.

  17. Quantitative isolation of biocontrol agents Trichoderma spp., Gliocladium spp. and actinomycetes from soil with culture media.

    Science.gov (United States)

    Vargas Gil, S; Pastor, S; March, G J

    2009-01-01

    Soil biodiversity plays a key role in the sustainability of agriculture systems and indicates the level of health of soil, especially when considering the richness of microorganisms that are involved in biological control of soilborne diseases. Cultural practices may produce changes in soil microflora, which can be quantified through the isolation of target microorganisms. Rhizosphere soil samples were taken from an assay with different crop rotations and tillage systems, and populations of Trichoderma spp., Gliocladium spp. and actinomycetes were quantified in order to select the general and selective culture media that better reflect the changes of these microbial populations in soil. The most efficient medium for the isolation of Trichoderma spp. and Gliocladium spp. was potato dextrose agar modified by the addition of chloramphenicol, streptomycin and rose bengal, and for actinomycetes was Küster medium, with cycloheximide and sodium propionate.

  18. Effects of two eflfux pump inhibitors on the drug susceptibility of Riemerella anatipestiferisolates from China

    Institute of Scientific and Technical Information of China (English)

    LI Ya-fei; JIANG Hong-xia; XIANG Rong; SUN Na; ZHANG Ya-nan; ZHAO Li-qing; GU Peng; WANG Li-qiao; ZENG Zhen-ling

    2016-01-01

    The objective of this study was to verify the supposition that eflfux might be involved in the drug resistance ofRiemerela anatipestiferisolates. Two broad-spectrum eflfux pump inhibitors, carbonyl cyanide 3-chlorophenylhydrazone (CCCP) and Phe-Arg-β-naphthylamide (PAβN), on the contribution of minimum inhibitory concentrations of amikacin, streptomycin, chloramphenicol, tetracycline, ceftriaxone, ceftazidime, nalidixic acid, levolfoxacin, enrolfoxacin, as wel as ciprolfoxacin against 69 clinicalR. anatipestiferisolates were investigated. We ifrst reported that the two eflfux pump inhibitors could restore the antimicrobial susceptibility ofR. anatipestifer isolates. It is suggested that active eflfux system is possible to be linked with the development of resistance inR. anatipestifer isolates.

  19. An easy method for plant polysome profiling

    DEFF Research Database (Denmark)

    Lecampion, Cécile; Floris, Maina Huguette Joséphine; Fantino, Jean Raphaël;

    2016-01-01

    Translation of mRNA to protein is a fundamental and highly regulated biological process. Polysome profiling is considered as a gold standard for the analysis of translational regulation. The method described here is an easy and economical way for fractionating polysomes from various plant tissues....... A sucrose gradient is made without the need for a gradient maker by sequentially freezing each layer. Cytosolic extracts are then prepared in a buffer containing cycloheximide and chloramphenicol to immobilize the cytosolic and chloroplastic ribosomes to mRNA and are loaded onto the sucrose gradient. After...... are then pooled to prepare three different mRNA populations: the polysomes, mRNAs bound to several ribosomes; the monosomes, mRNAs bound to one ribosome; and mRNAs that are not bound to ribosomes. mRNAs are then extracted. This protocol has been validated for different plants and tissues including Arabidopsis...

  20. Multi-residue and multi-class method for the determination of antibiotics in bovine muscle by ultra-high-performance liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Freitas, Andreia; Barbosa, Jorge; Ramos, Fernando

    2014-09-01

    A multi-residue quantitative screening method covering 41 antibiotics from 7 different families, by ultra-high-performance-liquid-chromatography tandem mass spectrometry (UHPLC-MS/MS), is described. Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol are simultaneously detected after a simple sample preparation of bovine muscle optimized to achieve the best recovery for all compounds. A simple sample treatment was developed consisting in an extraction with a mixture of acetonitrile and ethylenediaminetetraacetic acid (EDTA), followed by a defatting step with n-hexane. The methodology was validated, in accordance with Decision 2002/657/EC by evaluating the required parameters: decision limit (CCα), detection capability (CCβ), specificity, repeatability and reproducibility. Precision in terms of relative standard deviation was under 20% for all compounds and the recoveries between 91% and 119%. CCα and CCβ were determined according the maximum residue limit (MRL) or the minimum required performance limit (MRPL), when required.

  1. Construction of transgenic mice producing CAT to milk by co-injection of two overlapping fragments of bovine αs1-casein-CAT gene

    Institute of Scientific and Technical Information of China (English)

    劳为德; 刘伟; 成国祥; 徐少甫; 成勇

    1996-01-01

    Two αs1-casein/chloramphenicol acetyltransferase (CAT) gene constructs overlapping by 3.0kb were constructed and co-injected into murine zygotes. In 9 of 10 lines of transgenic mice obtained, based on analysis of structure and expression of the transgene, accurate extrachromosomal homologous recombination (ECR) between the two overlapping DNA fragments was found. Different levels of CAT activity were detected in milk from these lines. The highest CAT activity was about 25-50μg/mL milk. In some mice. CAT activity was found in salvia gland, thymus and spleen extracts. The high frequency and accuracy of ECR reported here will be applicable in the experimental manipulation for generation of relatively large transgene.

  2. Determinação simultânea de resíduos de cloranfenicol, tianfenicol e florfenicol em leite bovino por cromatografia eletrocinética micelar

    Directory of Open Access Journals (Sweden)

    Pezza Leonardo

    2006-01-01

    Full Text Available A micellar electrokinetic chromatographic method (MEKC is described for determining residues of amphenicols(chloramphenicol,thiamphenicol and florfenicol in bovine milk. MEKC is conducted by using a separation buffer consisting of 20 mM Na2HPO4, 10 mM Na2B4O7, 50 mM SDS at pH 8.0; UV detection at 210 nm and 10 kV of voltage. The limit of detection ranged from 4.3-5.3 µg L-1. The MEKC method was applied for the simultaneous determination of amphenicols in milk samples spiked with amphenicols at three concentration levels: 10, 30 and 50 µg L-1. Recoveries ranging from 91-105% were obtained by following a simple extraction/preconcentration procedure.

  3. Drug resistance and adherence to human intestines of enteroaggregative Escherichia coli.

    Science.gov (United States)

    Yamamoto, T; Echeverria, P; Yokota, T

    1992-04-01

    Clinical isolates of enteroaggregative Escherichia coli (EAggEC) were tested for their in vitro susceptibilities to 27 antimicrobial agents. Marked drug resistance was observed with sulfamethoxazole, ampicillin, and chloramphenicol in contrast to such antimicrobial agents as cefixime, sparfloxacin, and ciprofloxacin. One of the EAggEC strains carried a plasmid that conferred on its host resistance to ampicillin, tetracycline, sulfamethoxazole, streptomycin, and spectinomycin and an ability to adhere to child ileal villi or HeLa cells in the characteristic aggregative pattern. This plasmid also mediated D-mannose-resistant hemagglutinin production and bacterial clump formation (autoagglutination). The data demonstrate appearance of marked drug resistance and an intestine-adherence and drug-resistance plasmid in the newest category of diarrheagenic E. coli.

  4. Resistance of E. coli strains, recovered from chickens to antibiotics with particular reference to trimethoprim-sulfamethoxazole (septrin).

    Science.gov (United States)

    Bebora, L C; Oundo, J O; Yamamoto, H

    1994-10-01

    Thirty-seven strains of E. coli recovered from cases of septicaemia in chicken were tested for sensitivity to 6 antibiotics. Minimum inhibitory concentration (MIC) determinations done on the strains showed resistance to trimethoprim-sulfamethoxazole (septrin) (100%), ampicillin (62.2%), tetracycline (51.4%), kanamycin (13.5%) and gentamicin (2.7%). All were sensitive to chloramphenicol. Conjugation studies showed easy transfer of the resistance factor for septrin to the recipient sensitive strain, K12F-, a 60 megadalton plasmid was transferred in most of the cases (a number of plasmids moved across to K12F- strains). Septrin was chosen as a referral antibiotic because it is used extensively for treating diarrhoeal cases in children in Kenya. The results expressed the possibility of the chicken being the possible source of the septrin resistance gene (plasmid) for humans, and vice versa.

  5. Comparison of high sensitivity micro differential scanning calorimetry with X-ray powder diffractometry and FTIR spectroscopy for the characterization of pharmaceutically relevant non-crystalline materials.

    Science.gov (United States)

    Song, M; Liebenberg, W; De Villiers, M M

    2006-04-01

    In this study, high sensitivity micro differential scanning calorimetry (MDSC) in the scanning of dynamic mode was compared to X-ray powder diffractometry (XRPD) for quantifying amorphous nifedipine in mixtures crystalline nifedipine. This technique was also compared with FTIR for quantifying polymorph A of chloramphenicol palmitate (CAP) and poly DL-lactide-co-glycolide) (PLGA) in pharmaceutical formulations. The limit of determination (LOD) achieved by MDSC were 0.06% compared to 5% for XRPD quantification of amorphous nifedipine and 0.02% compared to 7% for IR quanitfication of polymorph A of CAP. As little as 0.165 mg PLGA could be measured in excipients mixtures. Desirable linearity and repeatability were established in all cases.

  6. Amino acid incorporation into the protein of mitochondrial preparations from cerebral cortex and spinal cord.

    Science.gov (United States)

    Bachelard, H S

    1966-07-01

    1. Washed guinea-pig cerebral-cortex mitochondria incorporate [(14)C]leucine into their protein at a rate comparable with the rates reported for liver or heart mitochondria only if the mitochondria are separated from myelin and nerve endings by density-gradient centrifugation. 2. The non-mitochondrial components (myelin and nerve endings) of brain mitochondrial preparations incorporated [(14)C]leucine at a negligible rate. 3. The mitochondria do not require an exogenous supply of energy or a full supply of amino acids to support the process. 4. The incorporation rate was linear up to 2hr. aerobic incubation at 30 degrees and was inhibited by chloramphenicol, only slightly by actinomycin D and not by penicillin or pretreatment with ribonuclease. The observed incorporation is considered to be unlikely to be due to contaminating cytoplasmic ribosomes or bacteria. 5. The process was also studied in mitochondrial preparations from rabbit cerebral cortex and spinal cord.

  7. Effect of protein synthesis inhibitors on the trophic action of the nerve stump.

    Science.gov (United States)

    Komatsu, K; Higashimori, E; Uchida, K; Satoh, S

    1983-06-01

    We report that protein synthesis inhibitors exert an inhibitory effect on the trophic action of the nerve stump. The sciatic nerve innervating the extensor digitorum longus muscles of mice was cut either as close to, or as far from, the muscle as possible. Denervation changes in the muscle were evaluated using the resting membrane potential and dose-response curves obtained by plotting acetylcholine-induced contractures. Actinomycin D (2 micrograms/kg, i.p.), ethidium bromide (10 micrograms/kg, i.p.), cycloheximide (1 or 5 mg/kg, i.p.), or chloramphenicol (100 mg/kg, p.o.) administration was immediately after neurotomy and continued daily until the day preceding muscle removal. Although denervation changes occurred significantly later in muscles with a long rather than a short nerve stump, the administrated antibiotics, excluding cycloheximide, accelerated the manifestation of denervation changes in muscles with long nerve stumps without affecting those in muscles with short nerve stumps.

  8. Studies on the ecology of aquatic bacteria of the lower Niger Delta: multiple antibiotic resistance among the standard plate count organisms.

    Science.gov (United States)

    Ogan, M T; Nwiika, D E

    1993-05-01

    The ecology of multiple antibiotic resistant (MAR) bacteria in the fresh-waters of the lower Niger Delta was studied in the Port Harcourt area, Rivers State. On the basis of decreasing pollution levels three zones, A, B, C, were recognized. Cell recovery by two viable count media, casein-peptone-starch (CPS) and plate count (PC) agar containing chloramphenicol, tetracycline, penicillin, streptomycin or ampicillin were compared in an initial study. Higher numbers of antibiotic resistant (AR) bacteria were recovered on CPS containing tetracycline, penicillin, streptomycin and ampicillin from the faecally-polluted New Calabar River (zone A) than on SPC agar containing similar antibiotics but the reverse was observed for forest stream (zone B) samples. Differences between the two media were also observed at individual sample sites. The proportions of strains of AR bacteria resistant to their primary isolation antibiotic varied from 55% (zone B) to 72% in the least polluted Isiokpo and Elele-Alimini streams (zone C), for ampicillin, and mostly count media without antibiotics included mainly species of Bacillus (12) and enterobacteria (18). Between five and 10 strains were resistant to > or = three antibiotics; seven were resistant to all five. The antibiograms of most strains were variable and depended on the method of drug application (discs or incorporation into agar), media and temperature of incubation (25 degrees, 37 degrees or 44.5 degrees C). Twenty-one strains were consistently resistant to ampicillin by the two methods; 10 to 19 were consistent for chloramphenicol, tetracycline and penicillin.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Prevalence and antimicrobial susceptibility of Vibrio parahaemolyticus isolated from retail shrimps in Malaysia

    Directory of Open Access Journals (Sweden)

    Vengadesh eLetchumanan

    2015-01-01

    Full Text Available Vibrio parahaemolyticus is a marine and estuarine bacterium that has been the leading cause of foodborne outbreaks which leads to a significant threat to human health worldwide. Consumption of seafood contaminated with Vibrio parahaemolyticus causes acute gastroenteritis in individuals. The bacterium poses two main virulence factor including the thermostable direct hemolysin (tdh which is a pore-forming protein that contributes to the invasiveness of the bacterium in humans and TDH-related hemolysin (trh, which plays a similar role as thermostable direct hemolysin (tdh in the disease pathogenesis. This study aimed to investigate the antimicrobial resistance Vibrio parahaemolyticus strains in shrimps purchased from wetmarkets and supermarkets. The toxR-based PCR assay indicated that a total of 57.8% (185/320 isolates were positive for V. parahaemolyticus. Only 10% (19/185 toxR-positive isolate exhibit the TDH-related hemolysin (trh gene and none of the isolates were tested positive for thermostable direct hemolysin (tdh. The MAR index was measured for 14 common antimicrobial agents. The results indicated 98% of the isolates were highly susceptible to imipenem, ampicillin sulbactam (96%, chloramphenicol (95%, trimethoprim-sulfamet (93%, gentamicin (85%, levofloxacin (83% and tetracycline (82%. The chloramphenicol (catA2 and kanamycin (aphA-3 resistance genes were detected in the resistant V. parahaemolyticus isolates. Our results demonstrate that shrimps are contaminated with V. parahaemolyticus, some of which carry the trh-gene thus being potential to cause food borne illness. The occurrence of multidrug resistance strains in the environment could be an indication of excessive usage of antibiotics in agriculture and aquaculture fields.

  10. Evidence on Possible Mycoplasma Etiology of Aster Yellows Disease II. Suppression of Aster Yellows in Insect Vectors.

    Science.gov (United States)

    Whitcomb, R F; Davis, R E

    1970-08-01

    Chlortetracycline or chloramphenicol (but not kanamycin, penicillin, or erythromycin), when administered in hydroponic solution to diseased aster, reduced the availability of the aster yellows (AY) agent to nymphs of Macrosteles fascifrons (Stål). Insects exposed to healthy plants whose roots were immersed in chlortetracycline were able to acquire AY agent from diseased plants the day after removal from the antibiotic-treated plants, but the latent period of the ensuing disease in the insects was prolonged. Chlortetracycline or tylosin tartrate blocked AY infection in nymphs injected with a mixture of antibiotic and the AY agent, but polymyxin, neomycin, vancomycin, penicillin, carbomycin, or chloramphenicol did not. All tetracyclines tested, methacycline, oxytetracycline, and chlortetracycline, produced a dramatic reduction in the ability of infected vectors to transmit AY agent. Tylosin tartrate also reduced transmission when injected into AY-transmitting vectors, but carbomycin, spectinomycin, cycloserine, penicillin, erythromycin, or kanamycin had no such effect. During the first 10 days after injection of tylosin tartrate or oxytetracycline into transmitting vectors, ability of the insects to transmit AY decayed rapidly. Transmission by insects injected with buffer alone, after decreasing the first day after injection, gradually returned to its normal level in less than 1 week. By 2 to 3 weeks after injection with tylosin or oxytetracycline, ability to transmit AY was regained by vectors. The results suggest that tetracycline antibiotics and tylosin tartrate inhibit multiplication of AY agent in the insect. The spectrum of antibiotic activity in the insect is consistent with the hypothesis that AY and other plant yellows diseases are caused by mycoplasma-like organisms.

  11. Antibiotic-Resistant Enteric Bacteria in Environmental Waters

    Directory of Open Access Journals (Sweden)

    Lisa M. Casanova

    2016-11-01

    Full Text Available Sources of antibiotic resistant organisms, including concentrated animal feeding operations (CAFOs, may lead to environmental surface and groundwater contamination with resistant enteric bacteria of public health concern. The objective of this research is to determine whether Salmonella, Escherichia coli, Yersinia enterocolitica, and enterococci resistant to clinically relevant antibiotics are present in surface and groundwater sources in two eastern North Carolina counties, Craven and Wayne. 100 surface and groundwater sites were sampled for Salmonella, E. coli, and enterococci, and the bacteria isolated from these samples were tested for susceptibility to clinically relevant antibiotics. Salmonella were detected at low levels in some surface but not groundwater. E. coli were in surface waters but not ground in both counties. Enterococci were present in surface water and a small number of groundwater sites. Yersinia was not found. Bacterial densities were similar in both counties. For Salmonella in surface water, the most frequent type of resistance was to sulfamethoxazole. There was no ciprofloxacin resistance. There were a few surface water E. coli isolates resistant to chloramphenicol, gentamicin, and ampicillin. Enterococci in surface water had very low levels of resistance to vancomycin, chloramphenicol, ampicillin, and streptomycin. E. coli and enterococci are present more frequently and at higher levels in surface water than Salmonella, but groundwater contamination with any of these organisms was rare, and low levels of resistance can be found sporadically. Resistant bacteria are relatively uncommon in these eastern N.C. surface and groundwaters, but they could pose a risk of human exposure via ingestion or primary contact recreation.

  12. Antibiotic resistant bacteria/genes dissemination in lacustrine sediments highly increased following cultural eutrophication of Lake Geneva (Switzerland).

    Science.gov (United States)

    Thevenon, Florian; Adatte, Thierry; Wildi, Walter; Poté, John

    2012-02-01

    This study investigates faecal indicator bacteria (FIB), multiple antibiotic resistant (MAR), and antibiotic resistance genes (ARGs), of sediment profiles from different parts of Lake Geneva (Switzerland) over the last decades. MARs consist to expose culturable Escherichia coli (EC) and Enterococcus (ENT) to mixed five antibiotics including Ampicillin, Tetracycline, Amoxicillin, Chloramphenicol and Erythromycin. Culture-independent is performed to assess the distribution of ARGs responsible for, β-lactams (blaTEM; Amoxicillin/Ampicillin), Streptomycin/Spectinomycin (aadA), Tetracycline (tet) Chloramphenicol (cmlA) and Vancomycin (van). Bacterial cultures reveal that in the sediments deposited following eutrophication of Lake Geneva in the 1970s, the percentage of MARs to five antibiotics varied from 0.12% to 4.6% and 0.016% to 11.6% of total culturable EC and ENT, respectively. In these organic-rich bacteria-contaminated sediments, the blaTEM resistant of FIB varied from 22% to 48% and 16% to 37% for EC and ENT respectively, whereas the positive PCR assays responsible for tested ARGs were observed for EC, ENT, and total DNA from all samples. The aadA resistance gene was amplified for all the sediment samples, including those not influenced by WWTP effluent water. Our results demonstrate that bacteria MARs and ARGs highly increased in the sediments contaminated with WWTP effluent following the cultural eutrophication of Lake Geneva. Hence, the human-induced changing limnological conditions highly enhanced the sediment microbial activity, and therein the spreading of antibiotic resistant bacteria and genes in this aquatic environment used to supply drinking water in a highly populated area. Furthermore, the presence of the antibiotic resistance gene aadA in all the studied samples points out a regional dissemination of this emerging contaminant in freshwater sediments since at least the late nineteenth century.

  13. Sewage sludge and liquid pig manure as possible sources of antibiotic resistant bacteria.

    Science.gov (United States)

    Hölzel, Christina S; Schwaiger, Karin; Harms, Katrin; Küchenhoff, Helmut; Kunz, Anne; Meyer, Karsten; Müller, Christa; Bauer, Johann

    2010-05-01

    Within the last decades, the environmental spread of antibiotic resistant bacteria has become a topic of concern. In this study, liquid pig manure (n=305) and sewage sludge (n=111) - used as agricultural fertilizers between 2002 and 2005 - were investigated for the presence of Escherichia coli, Enterococcus faecalis and Enterococcus faecium. Bacteria were tested for their resistance against 40 chemotherapeutics including several "reserve drugs". E. coli (n=613) from pig manure were at a significantly higher degree resistant to streptomycin, doxycycline, spectinomycin, cotrimoxazole, and chloramphenicol than E. coli (n=116) from sewage sludge. Enterococci (Ent. faecalis, n=387, and Ent. faecium, n=183) from pig manure were significantly more often resistant to high levels of doxycycline, rifampicin, erythromycin, and streptomycin than Ent. faecalis (n=44) and Ent. faecium (n=125) from sewage sludge. Significant differences in enterococcal resistance were also seen for tylosin, chloramphenicol, gentamicin high level, fosfomycin, clindamicin, enrofloxacin, moxifloxacin, nitrofurantoin, and quinupristin/dalfopristin. By contrast, aminopenicillins were more effective in enterococci from pig manure, and mean MIC-values of piperacillin+tazobactam and third generation cefalosporines were significantly lower in E. coli from pig manure than in E. coli from sewage sludge. 13.4% (E. coli) to 25.3% (Ent. faecium) of pig manure isolates were high-level multiresistant to substances from more than three different classes of antimicrobial agents. In sewage sludge, high-level-multiresistance reached from 0% (Ent. faecalis) to 16% (Ent. faecium). High rates of (multi-) resistant bacteria in pig manure emphasize the need for a prudent - cautious - use of antibiotics in farm animals.

  14. Laboratory-based surveillance of Neisseria meningitidis isolates from disease cases in Latin American and Caribbean countries, SIREVA II 2006-2010.

    Directory of Open Access Journals (Sweden)

    Ana Belén Ibarz-Pavón

    Full Text Available BACKGROUND: Published data on the epidemiology of meningococcal disease in Latin America and the Caribbean region is scarce and, when available, it is often published in Spanish and/or in non-peer-reviewed journals, making it difficult for the international scientific community to have access. METHODS: Laboratory data on 4,735 Neisseria meningitidis strains was collected and reported by the National Reference Laboratories in 19 Latin American countries and the Caribbean Epidemiology Centre (CAREC between 2006 and 2010 as part of the work carried out by the SIREVA II network. Serogroup and MIC to penicillin, rifampin and chloramphenicol were determined. RESULTS: Isolates were mainly obtained from patients <5 years, but each year around 25% of isolates came from adult patients. Serogroup distribution was highly variable among countries. Serogroup C was the main cause of disease in Brazil; the majority of disease seen in the Southern cone was caused by serogroup B, but serogroup W135 strains have increased in recent years. In the Andean and Mexico, Central America and Caribbean regions, serogroups B and C were equally present, and serogroup Y was frequently isolated. Isolates were generally susceptible to chloramphenicol, penicillin and rifampin, but almost 60% of isolates characterized in Southern cone countries presented intermediate resistance to penicillin. Five rifampin-resistant isolates have been isolated in Uruguay and Brazil. CONCLUSIONS: Serogroup distribution is highly variable among countries, but some geographic structuring can be inferred from these data. Epidemiological and laboratory data are scarce among Andean and Mexico, Central America and Caribbean countries. Evaluation and implementation of corrective measures on disease surveillance and reporting systems and the implementation of molecular diagnostic techniques and molecular characterization on meningococcal isolates are advised.

  15. Evidence for integration of retroviral vectors in a novel human repeat sequence

    Energy Technology Data Exchange (ETDEWEB)

    Kurdi-Haidar, B.; Friedmann, T. [USCD School of Medicine, La Jolla, CA (United States)

    1994-09-01

    Retroviruses have become attractive vehicles for the introduction of foreign genes into mammalian cells not only for gene therapy but also to serve as anchor points for long-range mapping purposes. The information relating to retroviral integration in mammalian cells is derived mostly from studies of rodent genomes. The absence of information regarding integration sites of murine-based retroviral vectors in human cells has prompted us to investigate the characteristics of integration sites in the human genome. We have constructed a Moloney murine leukemia virus-based retroviral vector that carries the pUC8 origin of replication and the chloramphenicol resistance gene to allow the rescue of the flanking genomic sequences in plasmid form. We have infected human primary fibroblasts and myoblasts with this retroviral vector and isolated independently transduced clones. Genomic DNA was obtained from independent clones and the genomic fragment carrying the provirus-host sequence boundary was isolated after digestion of the genomic DNA, circularization, and transformation by electroporation of E. coli C cells to chloramphenicol resistance. Restriction map and nucleotide sequence analysis of the rescued plasmids showed that a number of the clones shared the same integration site within the human genome. We have used the nucleotide sequence information about the human DNA adjacent to the 3{prime}LTR to design a PCR-based assay diagnostic for this common integration site. Analysis revealed the presence of the same integration site in four out of twelve human primary fibroblast clones infected with this specific retroviral vector, and in one out of twelve human primary myoblast clones infected with a second retroviral vector. Further analysis revealed the common integration site to be a previously unreported primate repeat present in monkey and human genomes and absent from rodent, bovine and avian genomes.

  16. Antimicrobial resistance in equine faecal Escherichia coli isolates from North West England

    Directory of Open Access Journals (Sweden)

    Williams Nicola J

    2010-04-01

    Full Text Available Abstract Background Escherichia coli isolates of equine faecal origin were investigated for antibiotic resistance, resistance genes and their ability to perform horizontal transfer. Methods In total, 264 faecal samples were collected from 138 horses in hospital and community livery premises in northwest England, yielding 296 resistant E. coli isolates. Isolates were tested for susceptibility to antimicrobial drugs by disc diffusion and agar dilution methods in order to determine minimum inhibitory concentrations (MIC. PCR amplification was used to detect genes conferring resistance to: ampicillin (TEM and SHV beta-lactamase, chloramphenicol (catI, catII, catIII and cml, tetracycline (tetA, tetB, tetC, tetD, tet E and tetG, and trimethoprim (dfrA1, dfrA9, dfrA12, dfrA13, dfr7, and dfr17. Results The proportion of antibiotic resistant isolates, and multidrug resistant isolates (MDR was significantly higher in hospital samples compared to livery samples (MDR: 48% of hospital isolates; 12% of livery isolates, p dfr, TEM beta-lactamase, tet and cat, conferring resistance to trimethoprim, ampicillin, tetracycline and chloramphenicol, respectively. Within each antimicrobial resistance group, these genes occurred at frequencies of 93% (260/279, 91%, 86.8% and 73.5%, respectively; with 115/296 (38.8% found to be MDR isolates. Conjugation experiments were performed on selected isolates and MDR phenotypes were readily transferred. Conclusions Our findings demonstrate that E. coli of equine faecal origin are commonly resistant to antibiotics used in human and veterinary medicine. Furthermore, our results suggest that most antibiotic resistance observed in equine E. coli is encoded by well-known and well-characterized resistant genes common to E. coli from man and domestic animals. These data support the ongoing concern about antimicrobial resistance, MDR, antimicrobial use in veterinary medicine and the zoonotic risk that horses could potentially pose to

  17. Anti Microbial Resistance Profile of E. coli isolates From Tropical Free Range Chickens

    Directory of Open Access Journals (Sweden)

    Okoli CI

    2005-12-01

    Full Text Available Normal intestinal flora of humans and animals constitute enormous reservoir of resistance genes for potentially pathogenic bacteria and may serve as major indictors of selection pressure exerted by anti-microbial use in a given population. A study was conducted in September 2003 at 3 purposively selected peri-urban sites spread across 3 senatorial zones of Imo state, Nigeria to determines the anti-microbial resistance profile of commensal E. coli isolated from free range chickens. The isolates were screened for anti-microbial resistance profile against 10 antibiotics using the disc diffusion method. E. coli strains from local fowls, recorded 100 and 78.9% resistances against ampicillin and cotrimoxazole respectively, while resistance rates against ciprofloxacin, gentamycin and norfloxacin were 0.0, 5.3 and 5.3% respectively. Isolates from free-range cockerels recorded 100% resistance against norfloxacin, cotrimoxazole and ampicillin and 83.3% against nitrofurantoin. Similarly, isolates from old layers, recorded 100% resistance against nitrofurantoin, cotrimoxazole, tetracycline, chloramphenicol and ampicillin and 80% against nalidixic acid. Similar resistance trends were observed in E. coli isolates from free-range turkeys and broiler roosters against the inexpensive broad-spectrum first line antibiotics (ampicillin, nalidixic acid, cotrimoxazole, nitrofurantoin and chloramphenicol, although values varied slightly across poultry types. Resistances against gentamycin were consistently low in isolates from the different types of poultry. Twenty-nine resistance patterns were observed in the E. coli isolates with predominant patterns being distributed widely across poultry types indicating a striking diversity of resistance patterns in the areas.

  18. Aspergillus niger, fungal pectinase, pomelo peels, solid state fermentation

    Directory of Open Access Journals (Sweden)

    Olarinmoye, A. O.

    2013-12-01

    Full Text Available Aims: This study investigated the antibiotic susceptibilities of avian pathogenic Escherichia coli (APEC isolates from layer chickens that died of colibacillosis, in the 6 states of Southwest Nigeria. Methodology and results: From bacteriological cultures of dead layers with suspected colibacillosis, 509 APEC isolates were identified by Gram staining, microscopy, and biochemical reactions, and tested by the Kirby-Bauer disc diffusion method for susceptibility to 9 human and veterinary antibiotics: Streptomycin (Str, 200 µg; Nitrofurantoin (Nit, 300 μg; Augmentin (Aug, 30 µg; Amoxicillin (Amo, 25 µg; Chloramphenicol (Chl, 30 µg; Gentamicin (Gen, 10 µg; Tetracycline (Tet, 25 μg; Ofloxacin (Ofl, 5 µg; and Fosfotrim (Fos, 30 μg. The APEC isolates were highly resistance to Amo (99.2%, Chloramphenicol (96.5%, Tet (91.4% and Ofl (86.4%; moderately resistant to Gen (67.2%, Aug (63.5%, Nit (51.7% and Fos (37.9%; while 14.3% of the isolates were resistant to Str at the test concentration of 200 µg, equivalent to ten times the normal disc test concentration. Overall, 39 antibiotic resistance patterns were observed, and more than 84.68% (n = 431 of the APEC isolates were multi-drug resistant. Conclusion, significance and impact of study: These results indicate that there is widespread misuse of antimicrobials in the poultry industry in Southwest Nigeria, and portend a high failure rate for the treatment of avian colibacillosis in the region. Owing to the public health importance of multidrug resistant bacteria that arise from animal production systems, there is need for exhaustive review of the regulatory framework guiding the supply and use of veterinary antimicrobials in Nigeria.

  19. ANTIBACTERIAL ACTIVITY OF SOME WILD MEDICAL PLANTS EXTRACT TO ANTIBIOTIC RESISTANT ESCHERICHIA COLI

    Directory of Open Access Journals (Sweden)

    Lukáš Hleba

    2013-02-01

    Full Text Available Antibiotics are probably the most successful family of drugs so far developed for improving human health. Because of increasing resistance to antibiotics of many bacteria, plant extracts and plant compounds are of new interest as antiseptics and antimicrobial agents in medicine. In this study, we researched antimicrobial effects of extracts of some medical plants (Tussilagofarfara, Equisetum arvense, Sambucusnigra, Aesculushippocastanumand Taraxacumofficinale from Slovakia to antibiotic resistant and antibiotic sensitive bacteria isolated from milk of cows and mare, which were breeded in different conditions. Microorganisms which were used in this experiment we isolated from milk from conventional breeding of cows (tenE. coli strains and from ecological breeding of Lipicanmare (tenE. coli strains by sterile cotton swabs. For antibiotic susceptibility testing was used disc diffusion method according by EUCAST. After dried at room temperature we weighed 50 g of crushed medical plants (parts and it were to extract in 400 ml methanol for two weeks at room temperature. For antimicrobial susceptibility testing of medical plants extract blank discs with 6 mm diameter disc diffusion method was used. We determined that all Escherichia coli strains isolated from milk of conventional breeding of cows were resistant to ampicillin and chloramphenicol. We determined that all tested ampicillin and chloramphenicol resistant E. coli strains isolated from conventional breeding of cow showed susceptibility to all used medical plants extracts. In difference, we determined that antibiotic susceptible E. coli strains isolated from ecological breeding of Lipicanmare were susceptible to Tussilagofarfara extract only. From these results we could be conclude some observations, which could be important step in treatment of bacterial infections caused by antibiotic resistant bacteria and it could be important knowledge for treatment of livestock in conventional breeding

  20. Induction of UDP-glucuronosyltransferase activities in Gunn, heterozygous, and Wistar rat livers by pregnenolone-16 alpha-carbonitrile.

    Science.gov (United States)

    Watkins, J B; Klaassen, C D

    1982-01-01

    The effect of pregnenolone-16 alpha-carbonitrile (PCN) on UDP-glucuronosyltransferase (UDP-GT) activity was comprehensively examined in Wistar (JJ), heterozygous (Jj) and Gunn (jj) rats with eleven different acceptors for glucuronic acid. UDP-GT activity after 3-methylcholanthrene (3-MC) and phenobarbital (PB) treatment was studied in additional rats for comparative purposes. Conjugation of group-1 aglycones (1-naphthol and p-nitrophenol) was much lower in Gunn than in Wistar rats. PCN did not alter UDP-GT conjugation of these acceptors. UDP-GT activity toward group-1 aglycones was increased by 3-MC in Wistar and heterozygous rats but was not enhanced in Gunn rats by any inducer. Activity toward group-2 aglycones (morphine, chloramphenicol, valproic acid) was similar in control rats of all genotypes. PCN increased chloramphenicol conjugation, whereas PB enhanced the glucuronidation of all group-2 aglycones in Wistar, heterozygous, and Gunn rats. Conjugation of group-3 acceptors (bilirubin and digitoxigenin monodigitoxoside, DIG) was deficient in Gunn rats and was not inducible. PCN increased glucuronidation of bilirubin and DIG in Wistar and heterozygous rats. The concentration of UDP-glucuronic acid (UDPGA) in liver was similar in control animals of all genotypes and was increased in rats treated with 3-MC. The other inducers did not affect hepatic UDPGA levels. Thus, 3-MC, PB, and PCN induce UDP-GT activities toward different groups of acceptors of glucuronic acid. The results support the hypothesis that PCN induces a form of UDP-GT that preferentially conjugates the group-3 acceptors, bilirubin and DIG.

  1. Antimicrobial resistance in bacteria isolated from aquatic environments in Brazil: a systematic review

    Directory of Open Access Journals (Sweden)

    Ermeton Duarte do Nascimento

    2014-04-01

    Full Text Available This article discusses antibiotic resistance in bacteria isolated from aquatic environments in Brazil, taking into account isolation sites, the main reported antimicrobial agents, the genes involved in resistance, the most prevalent bacterial genera and species, and the main mechanisms of resistance. This review is based upon specialized literature, consulting published scientific articles selected from the SciELO, PubMed and LILACS databases. Based upon the inclusion criteria, we selected 21 articles, most (61.6% were from PubMed, with the highest prevalence for work done in the Southeast region (71.4% in freshwater environments (71.4%, and the major focus on farm ponds (28.6%. Gram-negative bacteria are the most studied (71.4% and the Aeromonas spp. was the one found most frequently (19.0%. The most frequently used antimicrobials were chloramphenicol (81.0%, gentamicin (76.2%, sulpha/trimethroprim (71.4%, ampicillin (61.9% and tetracycline (71.4%; and the ones with higher prevalence of resistance were chloramphenicol (58.8%, sulpha/trimethroprim (78.5% and ampicillin (84.6%. It was found that studies on resistance in other aquatic environments have not yet been conducted in Brazil, especially in the North and Northeast regions, where irregular rainfall distribution leads to the use of reservoirs as supply sources during the dry season, highlighting concerns regarding the quality, contamination and maintenance of these resources, as the water is intended for human use or for production purposes.

  2. Occurrence, species distribution and antibiotic resistance of Proteus isolates: A case study at the Komfo Anokye Teaching Hospital (KATH in Ghana.

    Directory of Open Access Journals (Sweden)

    Patrick Kwame Feglo

    2010-10-01

    Full Text Available Background and purpose: Different Proteus species may vary with the type of infections they cause in both the community and hospital environments. However, in many laboratories in developing countries, differentiation of the genus Proteus into species is not generally done during bacteriological diagnosis due to high cost and special skills involved. This study aimed at determining the prevalence of different Proteus species in KATH, their antibiotic resistance attern and how they relate to patients’ demographic data. Method: This is a prospective study involving the analyses of clinical samples for Proteus species and determining their antimicrobial susceptibility pattern. Results: Two hundred Proteus species were isolated from 2361 clinical specimens obtained from patients suspectedof bacterial infection, giving 8.4 % prevalence of Proteus nfections. Wound isolates were the highest (64.5 % followed by ear swab. Three Proteus species; P. mirabilis, P. vulgaris and P. penneri were recovered from the samples. P. mirabilis was the commonest pecies (61.5 %, and hence the causative species of a majority of roteus infections followed by P. vulgaris (30.5 %, and P. penneri (8 %. There was no significant difference between the out-patient and in-patient cases, just as there were no preferences for gender or age of the patients. All the species were resistant to chloramphenicol, ampicillin and co-trimoxazole. About 72.9 % of the isolates produced β- lactamase and 88.5 % were resistant to more than 2 antibiotics. P. penneri was the most resistant among the recovered species. Conclusion: The three Proteus species recovered in KATH were all resistant to ampicillin, tetracycline, chloramphenicol and co-trimoxazole. These drugs are no longer useful in empirical treatment of Proteus infections at KATH. This study has also provided information for use in generating national data on the prevalence ofantimicrobial resistant pathogens in Ghana.

  3. Oxidative stress/reactive metabolite gene expression signature in rat liver detects idiosyncratic hepatotoxicants

    Energy Technology Data Exchange (ETDEWEB)

    Leone, Angelique; Nie, Alex; Brandon Parker, J.; Sawant, Sharmilee; Piechta, Leigh-Anne; Kelley, Michael F., E-mail: mkelley2@its.jnj.com; Mark Kao, L.; Jim Proctor, S.; Verheyen, Geert; Johnson, Mark D.; Lord, Peter G.; McMillian, Michael K.

    2014-03-15

    Previously we reported a gene expression signature in rat liver for detecting a specific type of oxidative stress (OS) related to reactive metabolites (RM). High doses of the drugs disulfiram, ethinyl estradiol and nimesulide were used with another dozen paradigm OS/RM compounds, and three other drugs flutamide, phenacetin and sulindac were identified by this signature. In a second study, antiepileptic drugs were compared for covalent binding and their effects on OS/RM; felbamate, carbamazepine, and phenobarbital produced robust OS/RM gene expression. In the present study, liver RNA samples from drug-treated rats from more recent experiments were examined for statistical fit to the OS/RM signature. Of all 97 drugs examined, in addition to the nine drugs noted above, 19 more were identified as OS/RM-producing compounds—chlorpromazine, clozapine, cyproterone acetate, dantrolene, dipyridamole, glibenclamide, isoniazid, ketoconazole, methapyrilene, naltrexone, nifedipine, sulfamethoxazole, tamoxifen, coumarin, ritonavir, amitriptyline, valproic acid, enalapril, and chloramphenicol. Importantly, all of the OS/RM drugs listed above have been linked to idiosyncratic hepatotoxicity, excepting chloramphenicol, which does not have a package label for hepatotoxicity, but does have a black box warning for idiosyncratic bone marrow suppression. Most of these drugs are not acutely toxic in the rat. The OS/RM signature should be useful to avoid idiosyncratic hepatotoxicity of drug candidates. - Highlights: • 28 of 97 drugs gave a positive OS/RM gene expression signature in rat liver. • The specificity of the signature for human idiosyncratic hepatotoxicants was 98%. • The sensitivity of the signature for human idiosyncratic hepatotoxicants was 75%. • The signature can help eliminate hepatotoxicants from drug development.

  4. Transposon insertion reveals pRM, a plasmid of Rickettsia monacensis.

    Science.gov (United States)

    Baldridge, Gerald D; Burkhardt, Nicole Y; Felsheim, Roderick F; Kurtti, Timothy J; Munderloh, Ulrike G

    2007-08-01

    Until the recent discovery of pRF in Rickettsia felis, the obligate intracellular bacteria of the genus Rickettsia (Rickettsiales: Rickettsiaceae) were thought not to possess plasmids. We describe pRM, a plasmid from Rickettsia monacensis, which was detected by pulsed-field gel electrophoresis and Southern blot analyses of DNA from two independent R. monacensis populations transformed by transposon-mediated insertion of coupled green fluorescent protein and chloramphenicol acetyltransferase marker genes into pRM. Two-dimensional electrophoresis showed that pRM was present in rickettsial cells as circular and linear isomers. The 23,486-nucleotide (31.8% G/C) pRM plasmid was cloned from the transformant populations by chloramphenicol marker rescue of restriction enzyme-digested transformant DNA fragments and PCR using primers derived from sequences of overlapping restriction fragments. The plasmid was sequenced. Based on BLAST searches of the GenBank database, pRM contained 23 predicted genes or pseudogenes and was remarkably similar to the larger pRF plasmid. Two of the 23 genes were unique to pRM and pRF among sequenced rickettsial genomes, and 4 of the genes shared by pRM and pRF were otherwise found only on chromosomes of R. felis or the ancestral group rickettsiae R. bellii and R. canadensis. We obtained pulsed-field gel electrophoresis and Southern blot evidence for a plasmid in R. amblyommii isolate WB-8-2 that contained genes conserved between pRM and pRF. The pRM plasmid may provide a basis for the development of a rickettsial transformation vector.

  5. Biocide and antibiotic resistance of Enterococcus faecalis and Enterococcus faecium isolated from the swine meat chain.

    Science.gov (United States)

    Rizzotti, Lucia; Rossi, Franca; Torriani, Sandra

    2016-12-01

    In this study nine strains of Enterococcus faecalis and 12 strains of Enterococcus faecium, isolated from different sample types in the swine meat chain and previously characterized for the presence of antibiotic resistance genes, were examined for phenotypic tolerance to seven biocides (chlorexidine, benzalkonium chloride, triclosan, sodium hypochlorite, 2-propanol, formaldehyde and hydrogen peroxide) and resistance to nine antibiotics (ampicillin, vancomycin, gentamicin, kanamycin, streptomycin, erythromycin, clindamycin, tetracycline and chloramphenicol). Moreover, the presence of efflux system encoding genes qacA/B, qacC, qacE, qacEΔ1, emeA, and stress response genes, sigV and gsp65, involved in the tolerance to biocides, was analysed. Most strains were not tolerant to the biocides, but showed minimum inhibitory concentrations (MICs) higher than the recommended cut-off values for all the antibiotics tested, except for vancomycin and chloramphenicol. Only weak correlations, if any, were found between biocide and antibiotic resistance data. One E. faecalis strain was tolerant to triclosan and one E. faecium strain, with higher tolerance to chlorexidine than the other strains tested, was found to carry a qacA/B gene. Our results indicated that phenotypic resistance to antibiotics is very frequent in enterococcal isolates from the swine meat chain, but phenotypic tolerance to biocides is not common. On the other hand, the gene qacA/B was found for the first time in the species E. faecium, an indication of the necessity to adopt measures suitable to control the spread of biocide resistance determinants among enterococci.

  6. Child morbidity of salmonellosis and the level of resistance of clinical isolates of salmonella to antibacterial preparations in saint Petersburg

    Directory of Open Access Journals (Sweden)

    N. V. Gonchar

    2015-01-01

    Full Text Available The aim of the study was to study the dynamics of the incidence of salmonellosis children in St. Petersburg and phenotypic resistance of clinical isolates of S. Enteritidis and S. Typhimurium to antibiotics in recent years. Materials and methods. The incidence of salmonellosis children studied according to the report for the first nine months of Rospotrebnadzor in 2013–2014. Incidence of salmonellosis in the structure of bacterial intestinal infections caused by pathogens in children hospitalized in the Department of intestinal infections in 2013–2014, studied according to annual reports. Antibiotic sensitivity was studied 86 Salmonella isolates (S. Enteritidis strain 64 and strain 22 S. Typhimurium, isolated from patients in children 2010–2014. Used the method of serial microdilution broth. Salmonella isolates were divided into sensitive, resistant, intermediate sensitivity to antibiotics. The Results. Analysis of the incidence of salmonellosis children of St. Petersburg has revealed its decline in 2014 (109.2 compared to 2013 (123,9 but relatively long-term average level was an increase in incidence (107,6. In the structure of salmonellosis in children prevailed salmonellosis Group D. In hospitalized children in the structure of bacterial intestinal infections detected Excess of share of salmonellosis in 2014 (36,9±3,4% compared to 2013 (24,5±2,4%; p <0,01. A reduction in the frequency sensitivity of S. Enteritidis to ampicillin, cefepime, ceftazidime and chloramphenicol. Compared to S. Enteritidis S. Typhimurium isolates were more resistant to ceftazidime and ampicillin, but more sensitive to ciprofloxacin. Conclusion. Morbidity of salmonellosis in recent years characterized by a relatively long-term average increase of the level. In the structure of salmonellosis in children prevailed salmonellosis Group D. There was a reduction of sensitivity S. Enteritidis isolates to cephalosporins new generations, and S. Typhimurium isolates

  7. Lysis-deficient phages as novel therapeutic agents for controlling bacterial infection

    Directory of Open Access Journals (Sweden)

    Kempashanaiah Nanjundappa

    2011-08-01

    Full Text Available Abstract Background Interest in phage therapy has grown over the past decade due to the rapid emergence of antibiotic resistance in bacterial pathogens. However, the use of bacteriophages for therapeutic purposes has raised concerns over the potential for immune response, rapid toxin release by the lytic action of phages, and difficulty in dose determination in clinical situations. A phage that kills the target cell but is incapable of host cell lysis would alleviate these concerns without compromising efficacy. Results We developed a recombinant lysis-deficient Staphylococcus aureus phage P954, in which the endolysin gene was rendered nonfunctional by insertional inactivation. P954, a temperate phage, was lysogenized in S. aureus strain RN4220. The native endolysin gene on the prophage was replaced with an endolysin gene disrupted by the chloramphenicol acetyl transferase (cat gene through homologous recombination using a plasmid construct. Lysogens carrying the recombinant phage were detected by growth in presence of chloramphenicol. Induction of the recombinant prophage did not result in host cell lysis, and the phage progeny were released by cell lysis with glass beads. The recombinant phage retained the endolysin-deficient genotype and formed plaques only when endolysin was supplemented. The host range of the recombinant phage was the same as that of the parent phage. To test the in vivo efficacy of the recombinant endolysin-deficient phage, immunocompromised mice were challenged with pathogenic S. aureus at a dose that results in 80% mortality (LD80. Treatment with the endolysin-deficient phage rescued mice from the fatal S. aureus infection. Conclusions A recombinant endolysin-deficient staphylococcal phage has been developed that is lethal to methicillin-resistant S. aureus without causing bacterial cell lysis. The phage was able to multiply in lytic mode utilizing a heterologous endolysin expressed from a plasmid in the propagation host

  8. Molecular Characterisation of Salmonella enterica Serovar Typhi Isolated from Typhoidial Humans

    Directory of Open Access Journals (Sweden)

    Arunava Das

    2012-09-01

    Full Text Available Aims: Salmonella enterica serovar Typhi is the major causative agent for typhoidial fever around the globe among human population reported till date. Present research work was carried out for detection and molecular characterisation of Salmonella enterica serovar Typhi isolated from humans with Typhoidial fever by biochemical, phenotypical and virulence gene based polymerase chain reaction (PCR techniques. The isolated strains were also investigated for antibiotic susceptibility patterns as a control measure. Methodology and Results: A total of 16 clinical samples were collected from the same numbers of patients (7 males and 9 females from Coimbatore, Erode and Salem districts of Tamil Nadu and were processed via broth enrichment methods for isolation and identification of the causative agent S. enterica serovar Typhi. Microbiological and biochemical investigations revealed the presence of S. Typhi from 16 samples. The biotyping of the isolates showed that all the isolates belonged to biotype IV. The PCR analysis confirmed the presence of invA (Invasion gene, 244bp, tyv (Tyveloseepimerase gene, 615 bp, fliC-d (Phage-1 flagellin gene for d-antigen, 750 bp and viaB (Vi antigen gene, 439bp in all 16 clinical samples. The antibiotic susceptibility test that was carried out among the isolates against 12 antimicrobial agents, showed 100 % resistance to only ampicillin and 100 % sensitivity to carbenicillin, chloramphenicol, clindamycin, gentamycin, kanamycin and tetracycline.Conclusion, significance and impact of study: This study confirmed the association of virulent strains of S. enterica serovar Typhi from Typhoidial fever among human population and suggested that PCR based diagnostic could be very useful for the rapid detection of S. Typhi isolates. Present study emphasized the use of antibiotic like chloramphenicol or in combination with other antibiotics for the effective control of S. Typhi.

  9. Antibiotic susceptibility of Salmonella spp.: a comparison of two surveys with a 5 years interval

    Directory of Open Access Journals (Sweden)

    Gordana Mijović

    2012-02-01

    Full Text Available Salmonella infections are one of the major global public health problems. During the last decade, antibiotic resistance and multiresistance of Salmonella spp. have increased a great deal, especially in developing countries with an increased and indiscriminate use of antibiotics in the treatment of humans and animals. This study aims to investigate and compare antimicrobial susceptibility patterns of Salmonella during 2005 and 2010.A total of 186 Salmonella strain during 2005 and 140 Salmonella strain during 2010 were isolated from stool specimens using standard methods. The isolates were confirmed as Salmonella by using a battery of biochemical reactions. Specific antisera were used for serologic characterization of Salmonella strain. Antimicrobial susceptibility testing was performed by standard disk diffusion method using ampicillin, trimethoprim-sulfamethoxasole, ceftriaxon, chloramphenicol, nalidixic acid and ciprofloxacin.One hundred eighty (96.8% of 186 isolated Salmonella strains in 2005, and 133 (95% of 140 isolated Salmonella strain in 2010 are recognized as Salmonella Enteritidis. Sensitivity of Salmonella isolates during 2005 and 2010 were 91.9% and 92.9% to ampicillin, 95.7% and 97.1% to trimethoprim-sulfamethoxasole, 99.5% and 100% to chloramphenicol, 99.5% and 100% to ciprofloxacin, 98.9% and 97.1% to ceftriaxon, 73.1% and 95.7% to nalidixic acid, respectively.Sensitivity of Salmonella isolates to all tested antimicrobial agents except to ceftriaxon was been slightly improved over testing period. Resistance rate to ceftriaxon was higher in 2010 than in 2005, and this fact deserves attention. Significantly increase susceptibility rate to nalidixic acid was observed between the two surveys

  10. Resistance phenotypes and genotypes of Salmonella enterica subsp. enterica isolates from feed, pigs, and carcasses in Brazil.

    Science.gov (United States)

    Lopes, Graciela Volz; Pissetti, Caroline; da Cruz Payão Pellegrini, Débora; da Silva, Luis Eduardo; Cardoso, Marisa

    2015-02-01

    Salmonella enterica subsp. enterica plays a role as a foodborne pathogen worldwide. The consumption of contaminated pork has been associated with human salmonellosis and the increase in antimicrobial resistance among Salmonella from pigs and pork products is a concern. A total of 225 Salmonella isolates from feed mills, the lairage environment, and the intestinal contents of pigs and carcasses were investigated for their antimicrobial susceptibility. A MIC for ciprofloxacin was screened by agar dilution, and antimicrobial resistance genes were investigated by PCR assays. Among the tested isolates, 171 (76%) showed resistance to at least one antimicrobial agent, and 91 (40.4%) were multiresistant. Resistance occurred most frequently to tetracycline (54.5%), sulfonamides (39.6%), and streptomycin (33.7%). Thirty-two (94.1%) nalidixic acid-resistant isolates exhibited decreased susceptibility to ciprofloxacin. The resistance genes found were blaTEM (ampicillin), tet(A) (tetracycline), tet(B) (tetracycline/minocycline), sul1, sul2, and sul3 (sulfonamides), catA1 (chloramphenicol), floR (florfenicol/chloramphenicol), strA and strB (streptomycin), aph(3')-Ia (kanamycin), aac(3)-IIa and aac(3)-IVa (apramycin/gentamicin), aadA variant (streptomycin/spectinomycin), and dfrA1 (trimethoprim). Salmonella isolates from pig feces and carcasses displayed a higher frequency of resistance to most antimicrobials tested than isolates from feed mills. Common resistance gene profiles were found in isolates from the lairage and the intestinal content of pigs and carcasses, demonstrating that resistance genes selected on farms may be found in pork.

  11. Cockroaches (periplaneta americana and blattella germanica: reservoirs of multi drug resistant (MDR bacteria in Uyo, Akwa Ibom State

    Directory of Open Access Journals (Sweden)

    E.P. Udoinyang

    2012-08-01

    Full Text Available Bacteriological examination of external surfaces and internal guts of Periplaneta americana and Blattela germanica were carried out using standard method and antibiotics susceptibility profiles of the isolates were determined using disc diffusion methods. Of the 317 bacteria isolated from the external surfaces and internal guts of P. americana, 275 (86.8% were Gram-negative bacilli, while 42 (13.2% were Gram-positive bacteria. Of the 204 bacterial isolates from B. germanica, 175 (85.8% were Gram negative, while 29 (14.2% were Gram positive bacteria. The bacteria isolated were Salmonella spp, Shigella spp, Staphylococcus aureus, coagulase negative Staphylococcus spp, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Citrobacter freundii, Morganella morganii, Proteus vulgaris, Proteus mirabilis, Enterobacter cloacae and Providencia spp. Among the Gram positive bacteria, only 75.8% S. aureus and 76.5% B. cereus were sensitive to Streptomycin and Gentamycin, while their resistance profiles to antibiotics in decreasing order were as follows: Chloramphenicol (41.7%, Amoxicillin (40.3%, Streptomycin (36.1%, Tetracycline (36.0%, Erythromycin (35.5%, Gentamicin (34.0%, Penicillin (34.6%, Cephalothin (27.8%, Sulfamethoxazole (23.4%, Ciprofloxacin (18.4% and Levofloxacin (17.7%. Less than 50% of E. cloacae and Providencia spp were resistant to Streptomycin, while ˂ 40% of P. vulgaris, K. pneumoniae, and P. aeruginosa were resistant to Chloramphenicol. Of the 353 (67.8% multi drug resistant bacteria, 121 (23.2% were resistant to 3 antibiotics, 232 (65.7% were resistant to 4-10 antibiotics. The antibiotic resistant Salmonella spp. and P. mirabilis had Multiple Antibiotic Resistance (MAR indexes ranging from 0.27 to 0.82. These findings suggest cockroaches in Uyo as potential vectors of medically important multiple drug-resistant bacteria.

  12. Interruption of the Calvin cycle inhibits the repair of Photosystem II from photodamage.

    Science.gov (United States)

    Takahashi, Shunichi; Murata, Norio

    2005-07-15

    In photosynthetic organisms, impairment of the activities of enzymes in the Calvin cycle enhances the extent of photoinactivation of Photosystem II (PSII). We investigated the molecular mechanism responsible for this phenomenon in the unicellular green alga Chlamydomonas reinhardtii. When the Calvin cycle was interrupted by glycolaldehyde, which is known to inhibit phosphoribulokinase, the extent of photoinactivation of PSII was enhanced. The effect of glycolaldehyde was very similar to that of chloramphenicol, which inhibits protein synthesis de novo in chloroplasts. The interruption of the Calvin cycle by the introduction of a missense mutation into the gene for the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) also enhanced the extent of photoinactivation of PSII. In such mutant 10-6C cells, neither glycolaldehyde nor chloramphenicol has any additional effect on photoinactivation. When wild-type cells were incubated under weak light after photodamage to PSII, the activity of PSII recovered gradually and reached a level close to the initial level. However, recovery was inhibited in wild-type cells by glycolaldehyde and was also inhibited in 10-6C cells. Radioactive labelling and Northern blotting demonstrated that the interruption of the Calvin cycle suppressed the synthesis de novo of chloroplast proteins, such as the D1 and D2 proteins, but did not affect the levels of psbA and psbD mRNAs. Our results suggest that the photoinactivation of PSII that is associated with the interruption of the Calvin cycle is attributable primarily to the inhibition of the protein synthesis-dependent repair of PSII at the level of translation in chloroplasts.

  13. In Vitro susceptibility of Gram-positive cocci isolated from skin and respiratory tract to azithromycin and twelve other antimicrobial agents

    Directory of Open Access Journals (Sweden)

    Caio M. F. Mendes

    2001-10-01

    Full Text Available This study was conducted to evaluate the activity of azithromycin in comparison to 12 other antibacterial agents against recent isolates obtained consecutively from patients with respiratory tract or skin infections, from January to July, 2000. A total of 717 Gram-positive cocci were analyzed in this study and the following species were studied: Staphylococcus aureus (n=576, beta-hemolytic streptococci ( n=115, and Streptococcus pneumoniae (n=26. Susceptibility testing was carried out by the disk diffusion method and interpreted according to NCCLS breakpoints. The activity of azithromycin was compared to erythromycin, clindamycin, chloramphenicol, ciprofloxacin, ofloxacin, oxacillin, penicillin, ceftriaxone, tetracycline, trimethoprim/sulfamethoxazole, teicoplanin, and vancomycin. Of the 26 S. pneumoniae isolates recovered from the respiratory tract, 5 (19.2% were intermediate resistant to penicillin. All of these strains were susceptible to chloramphenicol, ofloxacin, and vancomycin, and 24 (92% were also susceptible to azithromycin, clindamycin, and erythromycin. Among the 67 beta-hemolytic streptococci strains isolated from the respiratory tract, 66 (99% were susceptible to azithromycin, erythromycin, clindamycin, and ofloxacin. All 48 beta-hemolytic streptococci strains isolated from skin were susceptible to azithromycin and clindamycin, 47 (98% were susceptible to erythromycin, and 46 (96% were susceptible to ofloxacin. Of the 576 strains of S. aureus, 253 (43.9% were isolated from the respiratory tract and 323 (56.1% from skin. Among S. aureus isolates from the respiratory tract and skin, 46 (18% and 78 (24%, respectively were resistant to oxacillin. Isolates from the respiratory tract and skin showed the same percentage of resistance (36% to azithromycin. These in vitro results suggest that azithromycin can be a therapeutic option for treatment of infections caused by these bacteria since the newer macrolides have several distinct

  14. Characterization of culturable Paenibacillus spp. from the snow surface on the high Antarctic Plateau (DOME C) and their dissemination in the Concordia research station.

    Science.gov (United States)

    Van Houdt, Rob; Deghorain, Marie; Vermeersch, Marjorie; Provoost, Ann; Lo Giudice, Angelina; Leys, Natalie; Perez-Morga, David; Van Melderen, Laurence; Michaud, Luigi

    2013-07-01

    Culturable psychrotolerant bacteria were isolated from the top snow on the high Antarctic Plateau surrounding the research station Concordia. A total of 80 isolates were recovered, by enrichment cultures, from two different isolation sites (a distant pristine site [75° S 123° E] and a site near the secondary runway of Concordia). All isolates were classified to the genus Paenibacillus by 16S rRNA gene phylogenetic analysis and belonged to two different species (based on threshold of 97 % similarity in 16S rRNA gene sequence). ERIC-PCR fingerprinting indicated that the isolates from the two different sites were not all clonal. All isolates grew well from 4 to 37 °C and were resistant to ampicillin and streptomycin. In addition, the isolates from the secondary runway were resistant to chromate and sensitive to chloramphenicol, contrary to those from the pristine site. The isolates were compared to 29 Paenibacillus isolates, which were previously recovered from inside the Concordia research station. One of these inside isolates showed ERIC- and REP-PCR fingerprinting profiles identical to those of the runway isolates and was the only inside isolate that was resistant to chromate and sensitive to chloramphenicol. The latter suggested that dissemination of culturable Paenibacillus strains between the harsh Antarctic environment and the inside of the Concordia research station occurred. In addition, inducible prophages, which are potentially involved in horizontal dissemination of genes, were detected in Paenibacillus isolates recovered from outside and inside the station. The highest lysogeny was observed in strains harvested from the hostile environment outside the station.

  15. Evaluation of Petrifilm™ Select E. coli Count Plate medium to discriminate antimicrobial resistant Escherichia coli

    Directory of Open Access Journals (Sweden)

    Jensen Lars

    2008-09-01

    Full Text Available Abstract Background Screening and enumeration of antimicrobial resistant Escherichia coli directly from samples is needed to identify emerging resistant clones and obtain quantitative data for risk assessment. Aim of this study was to evaluate the performance of 3M™ Petrifilm™ Select E. coli Count Plate (SEC plate supplemented with antimicrobials to discriminate antimicrobial-resistant and non-resistant E. coli. Method A range of E. coli isolates were tested by agar dilution method comparing the Minimal Inhibitory Concentration (MIC for eight antimicrobials obtained by Mueller-Hinton II agar, MacConkey agar and SEC plates. Kappa statistics was used to assess the levels of agreement when classifying strains as resistant, intermediate or susceptible. Results SEC plate showed that 74% of all strains agreed within ± 1 log2 dilution when comparing MICs with Mueller-Hinton II media. High agreement levels were found for gentamicin, ampicillin, chloramphenicol and cefotaxime, resulting in a kappa value of 0.9 and 100% agreement within ± 1 log2 dilution. Significant variances were observed for oxytetracycline and sulphamethoxazole. Further tests showed that the observed discrepancy in classification of susceptibility to oxytetracycline by the two media could be overcome when a plate-dependent breakpoint of 64 mg/L was used for SEC plates. For sulphamethoxazole, SEC plates provided unacceptably high MICs. Conclusion SEC plates showed good agreement with Mueller-Hinton II agar in MIC studies and can be used to screen and discriminate resistant E. coli for ampicillin, cephalothin, streptomycin, chloramphenicol, cefotaxime and gentamicin using CLSI standardized breakpoints, but not for sulphamethoxazole. SEC plates can also be used to discriminate oxytetracycline-resistant E. coli if a plate-dependent breakpoint value of 64 mg/L is used.

  16. Prevalence and antimicrobial susceptibility of Vibrio parahaemolyticus isolated from retail shrimps in Malaysia.

    Science.gov (United States)

    Letchumanan, Vengadesh; Yin, Wai-Fong; Lee, Learn-Han; Chan, Kok-Gan

    2015-01-01

    Vibrio parahaemolyticus is a marine and estuarine bacterium that has been the leading cause of foodborne outbreaks which leads to a significant threat to human health worldwide. Consumption of seafood contaminated with V. parahaemolyticus causes acute gastroenteritis in individuals. The bacterium poses two main virulence factor including the thermostable direct hemolysin (tdh) which is a pore-forming protein that contributes to the invasiveness of the bacterium in humans and TDH-related hemolysin (trh), which plays a similar role as tdh in the disease pathogenesis. This study aimed to investigate the antimicrobial resistance V. parahaemolyticus strains in shrimps purchased from wetmarkets and supermarkets. The toxR-based PCR assay indicated that a total of 57.8% (185/320) isolates were positive for V. parahaemolyticus. Only 10% (19/185) toxR-positive isolate exhibit the trh gene and none of the isolates were tested positive for tdh. The MAR index was measured for 14 common antimicrobial agents. The results indicated 98% of the isolates were highly susceptible to imipenem, ampicillin sulbactam (96%), chloramphenicol (95%), trimethoprim-sulfamethoxazole (93%), gentamicin (85%), levofloxacin (83%), and tetracycline (82%). The chloramphenicol (catA2) and kanamycin (aphA-3) resistance genes were detected in the resistant V. parahaemolyticus isolates. Our results demonstrate that shrimps are contaminated with V. parahaemolyticus, some of which carry the trh-gene thus being potential to cause food borne illness. The occurrence of multidrug resistance strains in the environment could be an indication of excessive usage of antibiotics in agriculture and aquaculture fields.

  17. Contamination of Ethiopian paper currency notes from various food handlers with E. coli.

    Science.gov (United States)

    Hiko, Adem; Abdata, Kasahun; Muktar, Yimer; Woyesa, Mezene; Mohammed, Abdela

    2016-01-01

    Contamination rate of Ethiopian paper currency notes handled by various food handlers with Escherichia coli and antimicrobial susceptibility of the isolates was assessed. A total of 384 Ethiopian Birr (ETB) notes were randomly sampled from meat handlers at butchers, bread and the related food handlers at cafeteria, fruit and vegetables handlers at supermarket, and milk sellers both at open market and dairy station. Fifty control new currencies were also sampled from Commercial Bank of Ethiopia. Both surfaces of the currency were swabbed using wet sterile cotton. The swab was overnight incubated in buffered peptone water. A loop full was streaked on eosin methylene blue agar and followed by biochemical test on presumptive E. coli colonies. Randomly selected isolates were exposed to chloramphenicol (C-30 µg), neomycin (N-30 µg), oxytetracycline (OT-30 µg), polymyxin-B (PB-300 IU) and trimethoprim-sulfamethoxazole (SXT-1.25/23.75/µg) susceptibility using disc diffusion techniques. E. coli was not isolated from currency used as control. A total of 288 (75 %) currency notes were found carrying E. coli. E. coli prevalence was ranges from 67.2 % at open market milk sellers to 87.2 % at dairy station milk sellers; from 64.8 % on ETB 100 to 82.9 % on ETB 1. Differences were not observed in E. coli prevalence on currency notes from among almost all food handlers (P > 0.05). Susceptibility of tested isolates to each chloramphenicol, oxytetracycline and trimethoprim-sulfamethoxazole was 100 %, and to polymyxin-B was 97.3 %. High resistance (83.7 %) was observed to neomycin. The finding indicates, contaminated food can be a source of E. coli for further contamination of currency which again transfer through various foods ready for consumption.

  18. Prevalence of Aeromonas Hydrophila and Yersinia Enterocolitica in Children with Acute Diarrhea Attending Health Centers in Hamadan

    Directory of Open Access Journals (Sweden)

    S. Kazemi

    2016-01-01

    Full Text Available Introduction & Objective: Diarrhea is the most common cause of morbidity and mortality in all age groups, especially children, the elderly and immunocompromised patients. Various studies have been reported regarding the relationship between the children acute diarrhea and Aeromonashydrophila and Yersinia enterocolitica. This study aimed to investigate the prevalence of the bacteria and their sensitivity to common antibiotics and the prevalence of virulence genes in the bacteria in Hamadan, Iran. Materials & Methods: In this study, 120 stool samples collected from children less than 10 years of age with acute diarrhea were examined for Aeromonashydrophila and Yersinia enterocolitica. Identification of the bacteria was performed by biochemical reactions and PCR using 16S rRNA genes. Moreover, the prevalence of virulence genes earA and hyl of Aeromonashydrophila and ail and ystB genes of Yersinia enterocolitica were investigated using PCR. Antibiotic susceptibility of isolated bacteria was performed by disk diffusion method. Results: Out of 120 stool samples, 2 (1.7 % Aeromonashydrophila and 3 (2.5% Yersinia enterocolitica were isolated. All isolates of Aeromonashydrophila were sensitive to the chloramphenicol, co-trimoxazole, gentamicin, meropenem, amikacin and 50% of isolates were sensitive to the ceftriaxone and azithromycin. All Aeromonashydrophila isolates were resistant to erythromycin. All isolates of Yersinia enterocolitica were sensitive to the chloramphenicol, co-trimoxazole and meropenem. The 33.3% of the isolates were sensitive to gentamicin and amikacin and 66.6% of them were susceptible to ceftriaxone. However, all of Yersinia enterocolitica isolates were resistant to erythromycin and azithromycin. The prevalence aerA and hyl genes in Aeromonashydrophila were reported 100% and 50%, respectively. The prevalence of ail and ystB genes in Yersinia enterocolitica was reported as 66.6%. Conclusions: Identification and analysis of

  19. Genotypes, Virulence Factors and Antimicrobial Resistance Genes of Staphylococcus aureus Isolated in Bovine Subclinical Mastitis from Eastern China

    Directory of Open Access Journals (Sweden)

    Javed Memon§, Yongchun Yang§, Jam Kashifa, Muhammad Yaqoob, Rehana Buriroa, Jamila Soomroa, Wang Liping and Fan Hongjie*

    2013-11-01

    Full Text Available This study was carried out to determine the genotypes, virulence factors and antimicrobial resistance traits of 34 Staphylococcus aureus isolated from subclinical mastitis in Eastern China. Minimal inhibitory concentration (MIC results showed resistance to erythromycin in all isolates. A high frequency of Methicillin resistant S. aureus (MRSA; 29% was observed and these isolates were also highly resistant to penicillin, oxacillin, oxytetracycline and chloramphenicol than methicillin sensitive S. aureus (MSSA isolates. Thirteen pathogenic factors and seven resistance genes including mecA and blaZ gene were checked through PCR. The spaX gene was found in all isolates, whereas cna, spaIg, nuc, clfA, fnbpB, hlA, hlB and seA were present in 35, 79, 85, 59, 35, 85, 71 and 38% isolates, respectively. Nine isolates carried a group of 8 different virulence genes. Moreover, macrolide resistance genes ermB and ermC were present in all isolates. High resistance rate against methicillin was found but no isolate was positive for mecA gene, whereas blaZ and tetK were detected in 82 and 56% isolates, respectively. Genes; fnbpA, seB, seC, seD, dfrK and tetM were not found in any isolate. The statistical association between phenotypic resistance and virulence genes showed, clfA, fnbpB, hlB and seA, were potentially associated with penicillin G, ciprofloxacin, methicillin, chloramphenicol, trimethoprim and oxytetracycline resistance (P≤0.05. REP-PCR based genotyping showed seven distinct genotypes (A-G prevalent in this region. This study reports the presence of multidrug resistant S. aureus in sub-clinical mastitis which were also highly virulent that could be a major obstacle in the treatment of mastitis in this region of China.

  20. Antimicrobial peptides from arachnid venoms and their microbicidal activity in the presence of commercial antibiotics.

    Science.gov (United States)

    Garcia, Francia; Villegas, Elba; Espino-Solis, Gerardo Pavel; Rodriguez, Alexis; Paniagua-Solis, Jorge F; Sandoval-Lopez, Gabriel; Possani, Lourival D; Corzo, Gerardo

    2013-01-01

    Two antimicrobial peptides (AMPs), named La47 and Css54, were isolated from the venom of the spider Lachesana sp. and from the scorpion Centruroides suffusus suffusus, respectively. The primary structures of both La47 and Css54 were determined using N-terminal sequencing and mass spectrometry. La47 is identical to the AMP latarcin 3a obtained previously from the venom of the spider Lachesana tarabaevi, but the primary structure of Css54 is unique having 60% identities to the AMP ponericin-W2 from the venom of the ant Pachycondyla goeldii. Both La47 and Css54 have typical α-helix secondary structures in hydrophobic mimicking environments. The biological activities of both La47 and Css54 were compared with the AMP Pin2 isolated from the venom of the scorpion Pandinus imperator. La47 has lower antimicrobial and hemolytic activities compared with Css54 and Pin2. In addition, La47 and Pin2 were evaluated in the presence of the commercial antibiotics, chloramphenicol, ampicillin, novobiocin, streptomycin and kanamycin. Interestingly, the best antimicrobial combinations were obtained with mixtures of La47 and Pin2 with the antibiotics chloramphenicol, streptomycin and kanamycin, respectively. Furthermore, the novel peptide Css54 was evaluated in the presence of antibiotics used for the treatment of tuberculosis, isoniazid, rifampicin, pyrazinamide and ethambutol. Although the mixtures of Css54 with isoniazid, pyrazinamide or ethambutol inhibit the growth of Staphylococcus aureus, the best effect was found with rifampicin. Overall, these data show a motivating outlook for potential clinical treatments of bacterial infections using AMPs and commercial antibiotics.