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Sample records for tropicalis clinical isolates

  1. Hemólise produzida por Candida tropicalis isoladas de amostras clínicas Hemolysis produced by Candida tropicalis isolates from clinical samples

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    Emanuele Júlio Galvão de França

    2010-06-01

    Full Text Available INTRODUÇÃO: Leveduras do gênero Candida são responsáveis pela maioria das infecções fúngicas em humanos. Candida tropicalis tem sido uma das mais comumente isoladas dentre as espécies não-albicans. O objetivo foi analisar a hemólise in vitro promovida por isolados clínicos de C. tropicalis provenientes de sangue e outras amostras clínicas de pacientes internados no Hospital Universitário da UEL, PR-Brasil. MÉTODOS: Foi avaliada a hemólise promovida por 28 isolados clínicos de C. tropicalis, sendo os isolados agrupados em classes de acordo com os níveis de hemólise. RESULTADOS: A maioria dos isolados de sangue apresentou hemólise fraca (+, enquanto as classes de hemólise forte (+++ e muito forte (++++ foram as predominantes nos isolados de outras amostras clínicas como urina, lesão de unha e secreção traqueal, embora não tenham sido detectadas diferenças estatísticas (p>0,05. CONCLUSÕES: Isolados de C. tropicalis, obtidos de diferentes amostras clínicas, apresentam capacidade de promover hemólise in vitro.INTRODUCTION: Yeasts belonging to the genus Candida are responsible for the majority of fungal infections in humans. Candida tropicalis has been one of most commonly isolated non-albicans species. To analyze in vitro hemolysis promoted by clinical isolates of C. tropicalis obtained from blood and other clinical samples from hospitalized patients at the University Hospital of Londrina State University, Paraná, Brazil. METHODS: The hemolysis promoted by 28 clinical isolates of C. tropicalis was evaluated, and the isolates were grouped into classes according to the hemolysis levels. RESULTS: The majority of the blood isolates showed weak hemolysis (+, while the classes of strong hemolysis (+++ and very strong hemolysis (++++ predominated among isolates from other clinical samples such as urine, nail lesions and tracheal secretions. However, no statistical differences were detected (p> 0.05. CONCLUSIONS: Isolates of C

  2. Multilocus microsatellite markers for molecular typing of Candida tropicalis isolates.

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    Wu, Yuan; Zhou, Hai-jian; Che, Jie; Li, Wen-ge; Bian, Fu-ning; Yu, Shuan-bao; Zhang, Li-juan; Lu, Jinxing

    2014-11-20

    Candida tropicalis is considered to be the leading pathogen causing nosocomial fungemia and hepatosplenic fungal infections in patients with cancer, particularly those with leukemia. Microsatellite-based typing methods using sets of genetic markers have been developed and reported for population structure analysis of C. albicans, C. glabrata, and C. parapsilosis, but no studies have been published for genetic analysis of C. tropicalis. The objective of this study was to develop new microsatellite loci that have the ability to distinguish among C. tropicalis isolates. DNA sequences containing over 10 bi- or tri-nucleotide repeats were selected from the C. tropicalis genome database. Thirty PCR primers sets specific for the microsatellite loci were designed and tested using eight clinically independent isolates. According to the amplification efficiency, specificity, and observed polymorphisms, eight markers were selected for further population structure analysis and molecular typing. Sixty-five independent C. tropicalis isolates were genotyped using these 8 markers. Based on these analyses, six microsatellite loci were confirmed, although two loci were found to be with unstable flanking areas. The six polymorphic loci displayed 4-22 alleles and 7-27 genotypes. The discriminatory power of the six loci ranged from 0.70 to 0.95. Genotyping results obtained by microsatellite analysis were compared to PCR-fingerprinting and multi-locus sequence typing (MLST). The comparisons showed that microsatellite analysis and MLST had the similar discriminatory power for C. tropicalis, which were more powerful than PCR-fingerprinting. This is the first attempt to develop new microsatellite loci for C. tropicalis. These newly developed markers will be a valuable resource for the differentiation of C. tropicalis isolates. More C. tropicalis isolates will need to be sequenced and analyzed in order to fully show the potential of these newly developed microsatellite markers.

  3. Novel Polymorphic Multilocus Microsatellite Markers to Distinguish Candida tropicalis Isolates.

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    Fan, Xin; Xiao, Meng; Liu, Ping; Chen, Sharon; Kong, Fanrong; Wang, He; Zhang, Li; Hou, Xin; Xu, Ying-Chun

    2016-01-01

    Candida tropicalis is an important pathogen. Here we developed and evaluated a polymorphic multilocus microsatellite scheme employing novel genetic markers for genotyping of C. tropicalis. Using 10 isolates from 10 unique (separate) patients to screen over 4000 tandem repeats from the C. tropicalis genome (strain MYA-3404), six new candidate microsatellite loci (ctm1, ctm3, ctm8, ctm18, ctm24 and ctm26) were selected according to amplification success, observed polymorphisms and stability of flanking regions by preliminary testing. Two known microsatellite loci CT14 and URA3 were also studied. The 6-locus scheme was then tested against a set of 82 different isolates from 32 patients. Microsatellite genotypes of isolates from the same patient (two to five isolates per patient) were identical. The six loci produced eight to 17 allele types and identified 11 to 24 genotypes amongst 32 patients' isolates, achieving a discriminatory power (DP) of 0.76 to 0.97 (versus 0.78 for both CT14 and URA3 loci, respectively). Testing of a combination of only three loci, ctm1, ctm3 and ctm24, also achieved maximum typing efficiency (DP = 0.99, 29 genotypes). The microsatellite typing scheme had good correlation compared with pulsed-field gel electrophoresis, although was slightly less discriminatory. The new six-locus microsatellite typing scheme is a potentially valuable tool for genotyping and investigating microevolution of C. tropicalis.

  4. Clinical characteristics of the first cases of invasive candidiasis in China due to pan-echinocandin-resistant Candida tropicalis and Candida glabrata isolates with delineation of their resistance mechanisms

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    Xiao M

    2018-01-01

    Full Text Available Meng Xiao,1,2,* Xin Fan,1–3,* Xin Hou,1,2,4,* Sharon CA Chen,5 He Wang,1,2 Fanrong Kong,5 Zi-Yong Sun,6,* Yun-Zhuo Chu,7 Ying-Chun Xu1,2 1Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, People’s Republic of China; 2Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, People’s Republic of China; 3Department of Infectious Diseases and Clinical Microbiology, Beijing Chaoyang Hospital, Beijing, People’s Republic of China; 4Graduate School, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, People’s Republic of China; 5Center for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, The University of Sydney, NSW, Australia; 6Department of Clinical Laboratory, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, People’s Republic of China; 7Department of Clinical Laboratory, The First Affiliated Hospital of Chinese Medical University, Shenyang, People’s Republic of China *These authors contributed equally to this work Abstract: Echinocandin antifungal agents have become the first-line therapy for invasive candidiasis (IC in many countries. Despite their increasing use, resistance to this class of drug is, overall, still uncommon. Here, we report two patients from the People’s Republic of China with IC, one with infection caused by pan-echinocandin-resistant Candida tropicalis and the other by pan-echinocandin-resistant Candida glabrata. We also describe the mechanisms of drug resistance of these isolates. The echinocandin-resistant C. glabrata isolate was cultured from ascitic fluid of a 46-year-old male patient with intra-abdominal IC developing after surgery in 2012. This patient had had no prior antifungal exposure. The echinocandin-resistant C. tropicalis isolate was cultured from chest drainage

  5. Evaluation of Virulence FactorsIn vitro, Resistance to Osmotic Stress and Antifungal Susceptibility ofCandida tropicalisIsolated from the Coastal Environment of Northeast Brazil.

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    Zuza-Alves, Diana L; de Medeiros, Sayama S T Q; de Souza, Luanda B F C; Silva-Rocha, Walicyranison P; Francisco, Elaine C; de Araújo, Maria C B; Lima-Neto, Reginaldo G; Neves, Rejane P; Melo, Analy S de Azevedo; Chaves, Guilherme M

    2016-01-01

    Several studies have been developed regarding human health risks associated with the recreational use of beaches contaminated with domestic sewage. These wastes contain various micro-organisms, including Candida tropicalis . In this context, the objective of this study was to characterize C. tropicalis isolates from the sandy beach of Ponta Negra, Natal, Rio Grande do Norte, Brazil, regarding the expression of in vitro virulence factors, adaptation to osmotic stress and susceptibility to antifungal drugs. We analyzed 62 environmental isolates and observed a great variation among them for the various virulence factors evaluated. In general, environmental isolates were more adherent to human buccal epithelial cells (HBEC) than C. tropicalis ATCC13803 reference strain, and they also showed increased biofilm production. Most of the isolates presented wrinkled phenotypes on Spider medium (34 isolates, 54.8%). The majority of the isolates also showed higher proteinase production than control strains, but low phospholipase activity. In addition, 35 isolates (56.4%) had high hemolytic activity (hemolysis index > 0.55). With regard to C. tropicalis resistance to osmotic stress, 85.4% of the isolates were able to grow in a liquid medium containing 15% sodium chloride. The strains were highly resistant to the azoles tested (fluconazole, voriconazole and itraconazole). Fifteen strains were resistant to the three azoles tested (24.2%). Some strains were also resistant to amphotericin B (14 isolates; 22.6%), while all of them were susceptible for the echinocandins tested, except for a single strain of intermediate susceptibility to micafungin. Our results demonstrate that C. tropicalis isolated from the sand can fully express virulence attributes and showed a high persistence capacity on the coastal environment; in addition of showing high minimal inhibitory concentrations to several antifungal drugs used in current clinical practice, demonstrating that environmental isolates

  6. Evaluation of Virulence Factors In vitro, Resistance to Osmotic Stress and Antifungal Susceptibility of Candida tropicalis Isolated from the Coastal Environment of Northeast Brazil

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    Zuza-Alves, Diana L.; de Medeiros, Sayama S. T. Q.; de Souza, Luanda B. F. C.; Silva-Rocha, Walicyranison P.; Francisco, Elaine C.; de Araújo, Maria C. B.; Lima-Neto, Reginaldo G.; Neves, Rejane P.; Melo, Analy S. de Azevedo; Chaves, Guilherme M.

    2016-01-01

    Several studies have been developed regarding human health risks associated with the recreational use of beaches contaminated with domestic sewage. These wastes contain various micro-organisms, including Candida tropicalis. In this context, the objective of this study was to characterize C. tropicalis isolates from the sandy beach of Ponta Negra, Natal, Rio Grande do Norte, Brazil, regarding the expression of in vitro virulence factors, adaptation to osmotic stress and susceptibility to antifungal drugs. We analyzed 62 environmental isolates and observed a great variation among them for the various virulence factors evaluated. In general, environmental isolates were more adherent to human buccal epithelial cells (HBEC) than C. tropicalis ATCC13803 reference strain, and they also showed increased biofilm production. Most of the isolates presented wrinkled phenotypes on Spider medium (34 isolates, 54.8%). The majority of the isolates also showed higher proteinase production than control strains, but low phospholipase activity. In addition, 35 isolates (56.4%) had high hemolytic activity (hemolysis index > 0.55). With regard to C. tropicalis resistance to osmotic stress, 85.4% of the isolates were able to grow in a liquid medium containing 15% sodium chloride. The strains were highly resistant to the azoles tested (fluconazole, voriconazole and itraconazole). Fifteen strains were resistant to the three azoles tested (24.2%). Some strains were also resistant to amphotericin B (14 isolates; 22.6%), while all of them were susceptible for the echinocandins tested, except for a single strain of intermediate susceptibility to micafungin. Our results demonstrate that C. tropicalis isolated from the sand can fully express virulence attributes and showed a high persistence capacity on the coastal environment; in addition of showing high minimal inhibitory concentrations to several antifungal drugs used in current clinical practice, demonstrating that environmental isolates may

  7. Isolation of the alkane inducible cytochrome P450 (P450alk) gene from the yeast Candida tropicalis

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    The gene for the alkane-inducible cytochrome P450, P450alk, has been isolated from the yeast Candida tropicalis by immunoscreening a λgt11 library. Isolation of the gene has been identified on the basis of its inducibility and partial DNA sequence. Transcripts of this gene were i...

  8. An Update on Candida tropicalis Based on Basic and Clinical Approaches

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    Zuza-Alves, Diana L.; Silva-Rocha, Walicyranison P.; Chaves, Guilherme M.

    2017-01-01

    Candida tropicalis has emerged as one of the most important Candida species. It has been widely considered the second most virulent Candida species, only preceded by C. albicans. Besides, this species has been recognized as a very strong biofilm producer, surpassing C. albicans in most of the studies. In addition, it produces a wide range of other virulence factors, including: adhesion to buccal epithelial and endothelial cells; the secretion of lytic enzymes, such as proteinases, phospholipases, and hemolysins, bud-to-hyphae transition (also called morphogenesis) and the phenomenon called phenotypic switching. This is a species very closely related to C. albicans and has been easily identified with both phenotypic and molecular methods. In addition, no cryptic sibling species were yet described in the literature, what is contradictory to some other medically important Candida species. C. tropicalis is a clinically relevant species and may be the second or third etiological agent of candidemia, specifically in Latin American countries and Asia. Antifungal resistance to the azoles, polyenes, and echinocandins has already been described. Apart from all these characteristics, C. tropicalis has been considered an osmotolerant microorganism and this ability to survive to high salt concentration may be important for fungal persistence in saline environments. This physiological characteristic makes this species suitable for use in biotechnology processes. Here we describe an update of C. tropicalis, focusing on all these previously mentioned subjects. PMID:29081766

  9. ISOLATION OF THE CANDIDA TROPICALIS GENE FOR P450 LANOSTEROL DEMETHYLASE AND ITS EXPRESSION IN SACCAROMYCES CEREVISIAE

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    We have isolated the gene for cytochrome P450 lanosterol 14-demethylase (14DM) from the yeast Candida tropicalis. This was accomplished by screening genomic libraries of strain ATCC750 in E. coli using a DNA fragment containing the yeast Saccharomyces cerevisiae 14DM gene. Identi...

  10. Effect of Voriconazole on Candida tropicalis Biofilms: Relation with ERG Genes Expression.

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    Fernandes, Tânia; Silva, Sónia; Henriques, Mariana

    2016-10-01

    Candida tropicalis has emerged as the third most prevalent fungal pathogens and its ability to form biofilms has been considered one of the most important virulence factors, since biofilms represent high tolerance to antifungal agents. However, the mechanisms of C. tropicalis biofilm resistance to antifungals remain poorly understood. Thus, the main aim of this work was to infer about the effect of voriconazole on the formation and control of C. tropicalis biofilms and disclose its relationship with ERG genes' expression. Planktonic cells tolerance of several C. tropicalis clinical isolates to voriconazole was determined through of antifungal susceptibility test, and the effect of this azole against C. tropicalis biofilm formation and pre-formed biofilms was evaluated by cultivable cells determination and total biomass quantification. ERG genes expression was analyzed by quantitative real-time polymerase chain reaction. This work showed that C. tropicalis resistance to voriconazole is strain dependent and that voriconazole was able to partially control biofilm formation, but was unable to eradicate C. tropicalis pre-formed biofilms. Moreover, C. tropicalis biofilms resistance to voriconazole seems to be associated with alterations of sterol content in the cell membrane, resulting in ERG genes overexpression. Voriconazole is unable to control C. tropicalis biofilms, and the overexpression of ERG genes is a possible mechanism of biofilm resistance.

  11. Aerobic decolorization and degradation of azo dyes by growing cells of a newly isolated yeast Candida tropicalis TL-F1.

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    Tan, Liang; Ning, Shuxiang; Zhang, Xuwang; Shi, Shengnan

    2013-06-01

    The aim of this work was to investigate the decolorization and degradation of azo dyes by growing cells of a new yeast strain TL-F1 which was isolated from the sea mud. Strain TL-F1 was identified as Candida tropicalis on the basis of 28S rDNA analysis. Various azo dyes (20mg/L) were efficiently decolorized through aerobic degradation. Meantime, the effects of different parameters on both decolorization of Acid Brilliant Scarlet GR and growth of strain TL-F1 were investigated. Furthermore, possible degradation pathway of the dye GR was proposed through analysis of metabolic products using UV-Vis spectroscopy and HPLC-MS methods. As far as it is known, it is the first systematic research on a C. tropicalis strain which is capable of efficiently decolorizing various azo dyes under aerobic condition. This work provides a potentially useful microbial strain TL-F1 for treatment of azo dye contaminated wastewater. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Effect of Eugenol on Cell Surface Hydrophobicity, Adhesion, and Biofilm of Candida tropicalis and Candida dubliniensis Isolated from Oral Cavity of HIV-Infected Patients

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    Suelen Balero de Paula

    2014-01-01

    Full Text Available Most Candida spp. infections are associated with biofilm formation on host surfaces. Cells within these communities display a phenotype resistant to antimicrobials and host defenses, so biofilm-associated infections are difficult to treat, representing a source of reinfections. The present study evaluated the effect of eugenol on the adherence properties and biofilm formation capacity of Candida dubliniensis and Candida tropicalis isolated from the oral cavity of HIV-infected patients. All isolates were able to form biofilms on different substrate surfaces. Eugenol showed inhibitory activity against planktonic and sessile cells of Candida spp. No metabolic activity in biofilm was detected after 24 h of treatment. Scanning electron microscopy demonstrated that eugenol drastically reduced the number of sessile cells on denture material surfaces. Most Candida species showed hydrophobic behavior and a significant difference in cell surface hydrophobicity was observed after exposure of planktonic cells to eugenol for 1 h. Eugenol also caused a significant reduction in adhesion of most Candida spp. to HEp-2 cells and to polystyrene. These findings corroborate the effectiveness of eugenol against Candida species other than C. albicans, reinforcing its potential as an antifungal applied to limit both the growth of planktonic cells and biofilm formation on different surfaces.

  13. Characterization of xylose reductase from Candida tropicalis ...

    African Journals Online (AJOL)

    USER

    2010-08-02

    Aug 2, 2010 ... Xylose reductase gene, enzyme cofactors and plasmids. E.coli BL21(DE3) was used as host strains for ... C. tropicalis xylose reductase gene was isolated from plasmid. pMD18-T (TaKaRa, Japan). Enzyme ..... the gels is instable, soft and even dissolve in the solution containing multivalent anions or high ...

  14. Identification and first report of Inonotus (Phellinus) tropicalis as an etiologic agent in a patient with chronic granulomatous disease

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    D.A. Sutton; E.H. Thompson; M.G. Rinaldi; P.C. Iwen; K.K. Nakasone; H.S. Jung; H.M. Rosenblatt; M.E. Paul

    2005-01-01

    Although isolates of filamentous basidiomycetes can usually be recognized in a clinical laboratory setting, identification is problematic, as they seldom exhibit diagnostic morphological features formed in nature. This paper is the first report of Inonotus (Phellinus ) tropicalis inciting human disease and describes the methods used to support the identification.

  15. Azasordarins: Susceptibility of Fluconazole-Susceptible and Fluconazole-Resistant Clinical Isolates of Candida spp. to GW 471558

    OpenAIRE

    Cuenca-Estrella, Manuel; Mellado, Emilia; Díaz-Guerra, Teresa M.; Monzón, Araceli; Rodríguez-Tudela, Juan L.

    2001-01-01

    The in vitro activity of the azasordarin GW 471558 was compared with those of amphotericin B, flucytosine, itraconazole, and ketoconazole against 177 clinical isolates of Candida spp. GW 471558 showed potent activity against Candida albicans, Candida glabrata, and Candida tropicalis, even against isolates with decreased susceptibility to azoles. Candida krusei, Candida parapsilosis, Candida lusitaniae, and Candida guilliermondii are resistant to GW 471558 in vitro (MICs, >128 μg/ml).

  16. [Antifungal activity of melanin in clinical isolates of Candida spp].

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    Fuentes, Marisol; Hernández, Romané; Gordillo, Diego; Amaro, José; Falconer, Mary A; Alburquenque, Claudio; Tapia, Cecilia V

    2014-02-01

    Melanocytes are cells located in epidermis and mucous membranes that synthesize melanin and cytokines. It is known that melanin has antimicrobial activity and that melanocytes are melanized in presence of microbial molecules. To study the antifungal activity of melanin on Candida spp. The minimum inhibitory concentration (MIC) to melanin was determined in 4 Candida ATCC strains (C. albicans SC5314, C. parapsilosis 22019, C. glabrata 2001, C. krusei 6258) and 56 clinical isolates of Candida spp. (33 C. albicans, 12 C. glabrata, 3 C. famata, 3 C. krusei, 3 C. parapsilosis, 2 C. tropicalis) using a broth microdilution method. In addition, the antifungal activity of melanocytes and mice melanoma cells was tested against C. albicans. Melanin inhibited the tested isolates, including the susceptible dose-dependent and fluconazole-resistant strains; MIC range and MIC50 were 0.09-50 μg/mL and 6.25 μg/mL, respectively. Pigmented cells lysates inhibited C. albicans. Melanin is able to inhibit clinical isolates of Candida spp. Melanization could be an important protective mechanism of melanocytes.

  17. Clinically isolated laryngeal sarcoidosis

    DEFF Research Database (Denmark)

    Plaschke, Christina Caroline; Owen, Hanne Hoejris; Rasmussen, Niels

    2011-01-01

    to a combination of CO(2)-laser excision of supraglottic tissue and closure of the incision with sutures. All serological tests were negative or normal, including angiotensin 1 converting enzyme. The clinical expression was uniform with pale, smooth swellings of the supraglottic structures. Surgery proved...

  18. Multilocus Sequence Typing for Differentiation of Strains of Candida tropicalis

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    Tavanti, Arianna; Davidson, Amanda D.; Johnson, Elizabeth M.; Maiden, Martin C. J.; Shaw, Duncan J.; Gow, Neil A. R.; Odds, Frank C.

    2005-01-01

    A system is described for typing isolates of the pathogenic fungus Candida tropicalis, based on sequence polymorphisms in fragments of six genes: ICL1, MDR1, SAPT2, SAPT4, XYR1, and ZWF1a. The system differentiated 87 diploid sequence types (DSTs) among a total of 106 isolates tested or 80 DSTs among 88 isolates from unique sources. Replicate isolates from the same source clustered together with high statistical similarity, with the exception of one isolate. However, a clade of very closely related isolates included replicate isolates from three different patients, as well as single isolates from eight other patients. This clade, provisionally designated clade 1, was one of three clusters of isolates with high statistical similarity. Five of six isolates in one cluster that may acquire clade status were resistant to flucytosine. This study adds C. tropicalis to Candida albicans and Candida glabrata as Candida species for which a multilocus sequence typing (MLST) system has been set up. The C. tropicalis MLST database can be accessed at http://pubmlst.org/ctropicalis/. PMID:16272492

  19. Recurrent episodes of Candidemia due to Candida glabrata, Candida tropicalis and Candida albicans with acquired echinocandin resistance

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    Marine Grosset

    2016-12-01

    Full Text Available Mixed fungal infection and acquired echinocandin resistance of Candida spp. remain infrequent. In this study we have reported the case of a patient hospitalized for tuberculosis who experienced multiple infections due to three common Candida species (C. albicans, C. glabrata, C. tropicalis. Furthermore, consecutive isolates from blood cultures and heart valve were found resistant to azoles (C. tropicalis and to echinocandin with either novel (C. tropicalis or previously described (C. albicans missense mutations in the Fks gene.

  20. Targeted integration of genes in Xenopus tropicalis

    DEFF Research Database (Denmark)

    Shi, Zhaoying; Tian, Dandan; Xin, Huhu

    2017-01-01

    With the successful establishment of both targeted gene disruption and integration methods in the true diploid frog Xenopus tropicalis, this excellent vertebrate genetic model now is making a unique contribution to modelling human diseases. Here, we summarize our efforts on establishing homologous...... recombination-mediated targeted integration in Xenopus tropicalis, the usefulness, and limitation of targeted integration via the homology-independent strategy, and future directions on how to further improve targeted gene integration in Xenopus tropicalis....

  1. COPPER RESISTANT STRAIN CANDIDA TROPICALIS RomCu5 INTERACTION WITH SOLUBLE AND INSOLUBLE COPPER COMPOUNDS

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    Ie. P. Prekrasna

    2015-10-01

    Full Text Available The focus of the study was interaction of Candida tropicalis RomCu5 isolated from highland Ecuador ecosystem with soluble and insoluble copper compounds. Strain C. tropicalis RomCu5 was cultured in a liquid medium of Hiss in the presence of soluble (copper citrate and CuCl2 and insoluble (CuO and CuCO3 copper compounds. The biomass growth was determined by change in optical density of culture liquid, composition of the gas phase was measured on gas chromatograph, redox potential and pH of the culture fluid was defined potentiometrically. The concentration of soluble copper compounds was determined colorimetrically. Maximal permissible concentration of Cu2+ for C. tropicalis RomCu5 was 30 000 ppm of Cu2+ in form of copper citrate and 500 ppm of Cu2+ in form of CuCl2. C. tropicalis was metabolically active at super high concentrations of Cu2+, despite the inhibitory effect of Cu2+. C. tropicalis immobilized Cu2+ in the form of copper citrate and CuCl2 by it accumulation in the biomass. Due to medium acidification C. tropicalis dissolved CuO and CuCO3. High resistance of C. tropicalis to Cu2+ and ability to interact with soluble and insoluble copper compounds makes it biotechnologically perspective.

  2. Antifungal potential of eugenyl acetate against clinical isolates of Candida species.

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    Musthafa, Khadar Syed; Hmoteh, Jutharat; Thamjarungwong, Benjamas; Voravuthikunchai, Supayang Piyawan

    2016-10-01

    The study evaluated the efficiency of eugenyl acetate (EA), a phytochemical in clove essential oil, against clinical isolates of Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida glabrata. Minimum inhibitory concentrations (MIC) of EA against Candida isolates were in the range between 0.1% and 0.4% (v/v). Spot assay further confirmed the susceptibility of Candida isolates to the compound upon treatment with respective 1 × MIC. Growth profile measured in time kill study evidence that the compound at 1 × MIC and 1/2 × MIC retarded the growth of Candida cells, divulging the fungicidal activity. Light microscopic observation demonstrated that upon treated with EA, rough cell morphology, cell damage, and fragmented patterns were observed in C. albicans, C. parapsilosis, C. tropicalis, and C. glabrata. Furthermore, unusual morphological changes of the organism were observed in scanning electron microscopic study. Therefore, it is validated that the compound could cause cell damage resulting in the cell death of Candida clinical isolates. Eventually, the compound at sub-MIC (0.0125% v/v) significantly inhibited serum-induced germ tube formation by C. albicans. Eugenyl acetate inhibited biofilm forming ability of the organisms as well as reduced the adherence of Candida cells to HaCaT keratinocytes cells. In addition, upon treatment with EA, the phagocytic activity of macrophages was increased significantly against C. albicans (P Candida infections. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Evaluation of Bruker Biotyper and Vitek MS for the identification of Candida tropicalis on different solid culture media.

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    Wang, He; Li, Ying; Fan, Xin; Chiueh, Tzong-Shi; Xu, Ying-Chun; Hsueh, Po-Ren

    2017-11-11

    The aim of this study was to investigate the performance of the Bruker Biotyper matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and Vitek MS systems for identification of genetically-confirmed blood isolates of Candida tropicalis that had been grown on several types of culture media commonly used for primary fungal isolation. Isolates included 105 from the National China Hospital Invasive Fungal Surveillance Net program (CHIF-NET) and 120 from National Taiwan University Hospital (NTUH). Culture media tested for CHIF-NET isolates included trypticase soy agar supplemented with 5% sheep blood (BAP), Sabouraud dextrose agar (SDA-C), CHROMagar, China blue agar (CBA), chocolate agar supplemented with vancomycin (CAP-VA), and MacConkey agar (MAC). Culture media used for NTUH isolates included BAP, SDA, CHROMagar, eosin methylene blue (EMB), inhibitory mold agar (IMA), Mycosel agar, and cornmeal agar (CMA). The Bruker Biotyper correctly identified all CHIF-NET isolates to the species level on all six agar media tested and correctly identified the majority of NTUH isolates with the exception of isolates grown on SDA (85.8%) and CMA (52.5%). The Vitek MS system correctly identified all CHIF-NET isolates to the species level with the exception of isolates grown on CHROMagar (84.8%), and correctly identified the majority of NTUH isolates with the exception of isolates grown on SDA (51.7%), Mycosel agar (57.5%), and CMA (9.2%) for NTUH isolates. Clinical microbiologists should be aware that different culture media can affect the performance of the Bruker Biotyper MALDI-TOF MS and Vitek MS systems in identifying C. tropicalis. Copyright © 2017. Published by Elsevier B.V.

  4. Bioethanol Production From Cellulose by Candida tropicalis, as An Alternative Microbial Agent to Produce Ethanol from Lignocellulosic Biomass

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    Hermansyah

    2016-04-01

    Full Text Available Abstract: Candida tropicalis isolated from Tuak is a potentially useful microorganism for the ethanol production from lignocellulosic biomass and it can be alterbative agent replacing Saccharomyces cerevisae for fermentation process. Although C.tropicalis could not convert all carbohydrates content of lignocellulosic into bioethanol, however it is able to grow on medium in the presence of either xylose or arabinose as carbon source. Our result showed that fermentation of 10 % (w/v cellulosic as sole carbon source produced 2.88% (v/v ethanol by C.tropicalis. This ethanol production was lower than usage of 10% (w/v dextrose as sole carbon source medium which producing 5.51% (v/v ethanol. Based upon our expreiment indicated that C.tropicalis is able to conduct two main process in converting of cellulosic material- to ethanol which is hydrolysis the degradation of cellulose into glucose, and fermentation the process the conversion glucose into bioethanol. Keywords : Candida tropicalis, bioethanol, fermentation, cellulosic Abstrak (Indonesian: Candida tropicalis yang diisiolasi dari Tuak adalah agen yang berpotensi dalam produksi etanol dari biomasa lignoselulosa dan dapat dijadikan agen alternatif menggantikan Saccharomyces cerevisiae pada proses fernentasi. Walaupun C.tropicalis tidak dapat mengkonversi semua kandungan karbohidrat lignoselulosamenjadi etanol, akan tetapi C.tropicalis mampu tumbuh pada media dengan xilosa atau arabinosa sebagaisumber karbon. Hasil kami menunjukkan bahwa dengan mengguankan C.tropicalis fermentasi 10% (w/v selulosa sebagai satu-satunya sumber karbon menghasilkan 2,88% (v/v etanol, Produksi etanol ini lebih rendah jika menggunakan 10% (w/v dekstrosa sebagai satu satunya sumber karbon yang menghasilkan 5,51% (v/v etanol. Berdasarkan percobaan menunjukkan bahwa C.tropicalis mampu melakukan dua proses utama dalam mengkonversi material selulosa menjadi etanol yaitu hidrolisis degradasi selulosa menjadi glukosa, dan

  5. Oligotrophic bacteria isolated from clinical materials.

    OpenAIRE

    Tada, Y; Ihmori, M; Yamaguchi, J

    1995-01-01

    Oligotrophic bacteria (oligotrophs) are microorganisms that grow in extremely nutritionally deficient conditions in which the concentrations of organic substances are low. Many oligotrophic bacteria were isolated from clinical materials including urine, sputum, swabbings of the throat, vaginal discharges, and others. Seventy-seven strains of oligotrophic bacteria from 871 samples of clinical material were isolated. A relatively higher frequency of isolation of oligotrophic bacteria was shown ...

  6. Antifungal susceptibilities of Candida glabrata species complex, Candida krusei, Candida parapsilosis species complex and Candida tropicalis causing invasive candidiasis in China: 3 year national surveillance.

    Science.gov (United States)

    Xiao, Meng; Fan, Xin; Chen, Sharon C-A; Wang, He; Sun, Zi-Yong; Liao, Kang; Chen, Shu-Lan; Yan, Yan; Kang, Mei; Hu, Zhi-Dong; Chu, Yun-Zhuo; Hu, Tie-Shi; Ni, Yu-Xing; Zou, Gui-Ling; Kong, Fanrong; Xu, Ying-Chun

    2015-03-01

    To define the antifungal susceptibility patterns of the most common non-albicans Candida spp. in China. We evaluated the susceptibilities to nine antifungal drugs of Candida parapsilosis species complex, Candida tropicalis, Candida glabrata species complex and Candida krusei isolates from patients with invasive candidiasis at 11 hospitals over 3 years. Isolates were identified by MALDI-TOF MS supplemented by DNA sequencing. MICs were determined by Sensititre YeastOne(TM) using current clinical breakpoints/epidemiological cut-off values to assign susceptibility (or WT), and by CLSI M44-A2 disc diffusion for fluconazole and voriconazole. Of 1072 isolates, 392 (36.6%) were C. parapsilosis species complex. C. tropicalis, C. glabrata species complex and C. krusei comprised 35.4%, 24.3% and 3.7% of the isolates, respectively. Over 99.3% of the isolates were of WT phenotype to amphotericin B and 5-flucytosine. Susceptibility/WT rates to azoles among C. parapsilosis species complex were ≥97.5%. However, 11.6% and 9.5% of C. tropicalis isolates were non-susceptible to fluconazole and voriconazole, respectively (7.1% were resistant to both). Approximately 14.3% of C. glabrata sensu stricto isolates (n = 258) were fluconazole resistant, and 11.6% of C. glabrata sensu stricto isolates were cross-resistant to fluconazole and voriconazole. All C. krusei isolates were susceptible/WT to voriconazole, posaconazole and itraconazole. Overall, 97.7%-100% of isolates were susceptible to caspofungin, micafungin and anidulafungin, but 2.3% of C. glabrata were non-susceptible to anidulafungin. There was no azole/echinocandin co-resistance. Disc diffusion and Sensititre YeastOne(TM) methods showed >95% categorical agreement for fluconazole and voriconazole. In summary, reduced azole susceptibility was seen among C. tropicalis. Resistance to echinocandins was uncommon. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial

  7. Fermentation profile of Saccharomyces cerevisiae and Candida tropicalis as starter cultures on barley malt medium.

    Science.gov (United States)

    Alloue-Boraud, Wazé Aimée Mireille; N'Guessan, Kouadio Florent; Djeni, N'Dédé Théodore; Hiligsmann, Serge; Djè, Koffi Marcellin; Delvigne, Franck

    2015-08-01

    Saccharomyces cerevisiae C8-5 and Candida tropicalis F0-5 isolated from traditional sorghum beer were tested for kinetic parameters on barley malt extract, YPD (863 medium) and for alcohol production. The results showed that C. tropicalis has the highest maximum growth rate and the lowest doubling time. Values were 0.22 and 0.32 h(-1) for maximum growth rate, 3 h 09 min and 2 h 09 min for doubling time respectively on barley malt extract and YPD. On contrary, glucose consumption was the fastest with S. cerevisiae (-0.36 and -0.722 g/l/h respectively on barley malt extract and YPD). When these two yeasts were used as starters in pure culture and co-culture at proportion of 1:1 and 2:1 (cell/cell) for barley malt extract fermentation, we noticed that maltose content increased first from 12.12 g/l to 13.62-16.46 g/l and then decreased. The highest increase was obtained with starter C. tropicalis + S. cerevisiae 2:1. On contrary, glucose content decreased throughout all the fermentation process. For all the starters used, the major part of the ethanol was produced at 16 h of fermentation. Values obtained in the final beers were 11.4, 11.6, 10.4 and 10.9 g/l for fermentation conducted with S. cerevisiae, C. tropicalis, C. tropicalis + S. cerevisiae 1:1 and C. tropicalis + S. cerevisiae 2:1. Cell viability measurement during the fermentation by using flow cytometry revealed that the lowest mean channel fluorescence for FL3 (yeast rate of death) was obtained with C. tropicalis + S. cerevisiae 2:1 after 48 h of fermentation.

  8. Fermentation profile of Saccharomyces cerevisiae and Candida tropicalis as starter cultures on barley malt medium

    OpenAIRE

    Alloue-Boraud, Wazé Aimée Mireille; N’Guessan, Kouadio Florent; Djeni, N’Dédé Théodore; Hiligsmann, Serge; Djè, Koffi Marcellin; Delvigne, Franck

    2014-01-01

    Saccharomyces cerevisiae C8-5 and Candida tropicalis F0-5 isolated from traditional sorghum beer were tested for kinetic parameters on barley malt extract, YPD (863 medium) and for alcohol production. The results showed that C. tropicalis has the highest maximum growth rate and the lowest doubling time. Values were 0.22 and 0.32 h−1 for maximum growth rate, 3 h 09 min and 2 h 09 min for doubling time respectively on barley malt extract and YPD. On contrary, glucose consumption was the fastest...

  9. Species identification of Candida isolated from clinical specimens in a tertiary care hospital

    Directory of Open Access Journals (Sweden)

    lsmet Nigar

    2016-07-01

    Full Text Available Background: Candida species are responsible for various clinical manifestations from mucocutaneous overgrowth to blood stream infections especially in immunocompromized situations. Although C. albicans is the most prevalent species, high incidence of non-albicans Candida species with antifungal resistance are emerging which is posing a serious threat to the patients care.Objective: This study aimed to isolate and identify different species of Candida from different clinical specimens. Methods: A total of 100 different clinical specimens were studied of which 35 were oral swab, 28 were high vaginal swab, 15 were urine, 14 were nail, 04 were bronchoalveolar lavage and peritoneal fluid were 04. Among 100 clinical specimens, Candida isolates were identified in 64 specimens. Isolation of Candida species was done by primary culture in SDA. Subsequent identification of species were performed by germ tube test, subculture in chromo­genic agar medium and carbohydrate assimilation test with commonly used twelve sugars.Results: Out of 64 isolated Candida species, Candida albicans were 51.56% and the non-albicans Candida species were 48.44%. The most prevalent Candida species was C. albicans 33 (51.53% followed by C. tropicalis 17 (26.56%. C. glabrata 4 (6.25%, C. parapsilo­sis 4 (6.25%, C. krusei 3 (4.68% and C. guilliermondii 2 (3.2%. One of the isolated Candida species was unidentified.Conclusion: Though Candida albicans was found as the most common species, but non-albicans Candida species are appearing as emerging pathogens as well. Exposure to chemotherapy appeared to be the commonest predisposing factor for Candida infection followed by indwelling urinary catheter in situ for prolong period.

  10. Stepwise Development of a Homozygous S80P Substitution in Fks1p, Conferring Echinocandin Resistance in Candida tropicalis

    DEFF Research Database (Denmark)

    Jensen, Rasmus Hare; Johansen, Helle Krogh; Arendrup, Maiken Cavling

    2013-01-01

    Three Candida tropicalis isolates were obtained from a patient with acute lymphoblastic leukemia. The first isolate was susceptible to all drug classes, while isolates 2 and 3, obtained after 8 and 8.5 weeks of caspofungin treatment, respectively, were resistant to the three echinocandins...

  11. In vitro differential activity of phospholipases and acid proteinases of clinical isolates of Candida

    Directory of Open Access Journals (Sweden)

    Aurean D'Eça Júnior

    2011-06-01

    Full Text Available INTRODUCTION: Candida yeasts are commensals; however, if the balance of normal flora is disrupted or the immune defenses are compromised, Candida species can cause disease manifestations. Several attributes contribute to the virulence and pathogenicity of Candida, including the production of extracellular hydrolytic enzymes, particularly phospholipase and proteinase. This study aimed to investigate the in vitro activity of phospholipases and acid proteinases in clinical isolates of Candida spp. METHODS: Eighty-two isolates from hospitalized patients collected from various sites of origin were analyzed. Phospholipase production was performed in egg yolk medium and the production of proteinase was verified in a medium containing bovine serum albumin. The study was performed in triplicate. RESULTS: Fifty-six (68.3% of isolates tested were phospholipase positive and 16 (44.4% were positive for proteinase activity. C. tropicalis was the species with the highest number of positive isolates for phospholipase (91.7%. Statistically significant differences were observed in relation to production of phospholipases among species (p<0,0001 and among the strains from different sites of origin (p=0.014. Regarding the production of acid protease, the isolates of C. parapsilosis tested presented a larger number of producers (69.2%. Among the species analyzed, the percentage of protease producing isolates did not differ statistically (χ2=1.9 p=0.5901 (χ2=1.9 p=0.5901. CONCLUSIONS: The majority of C. non-albicans and all C. albicans isolates were great producers of hydrolytic enzymes and, consequently, might be able to cause infection under favorable conditions.

  12. [Comparison between conventional methods, ChromAgar Candida® and PCR method for the identification of Candida species in clinical isolates].

    Science.gov (United States)

    Estrada-Barraza, Deyanira; Dávalos Martínez, Arturo; Flores-Padilla, Luis; Mendoza-De Elias, Roberto; Sánchez-Vargas, Luis Octavio

    2011-01-01

    The increase in the incidence of yeast species causing fungemia in susceptible immunocompromised patients in the last two decades and the low sensitivity of conventional blood culture has led to the need to develop alternative approaches for the early detection and identification of causative species. The aim of this study was to compare the usefulness of molecular testing by the polymerase chain reaction (PCR) and conventional methods to identify clinical isolates of different species, using the ID32C ATB system (bioMérieux, France), chromogenic culture Chromagar Candida® (CHROMagar, France) and morphogenesis in corn meal agar. We studied 79 isolates, in which the most prevalent species using the system ID32C and PCR was C. albicans, followed by C. tropicalis, C. glabrata and C .krusei. PCR patterns obtained for the identification of clinical isolates were stable and consistent in the various independent studies and showed good reproducibility, concluding that PCR with species-specific primers that amplify genes ITS1 and ITS2 for rRNA or topoisomerase II primers is a very specific and sensitive method for the identification of C. glabrata, C. krusei, C. albicans, and with less specificity for C. tropicalis. Copyright © 2010 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  13. MALDI-TOF mass spectrometry for rapid identification of clinical fungal isolates based on ribosomal protein biomarkers.

    Science.gov (United States)

    Panda, Ashutosh; Ghosh, Anup K; Mirdha, Bijay R; Xess, Immaculata; Paul, Saikat; Samantaray, Jyotish C; Srinivasan, Alagiri; Khalil, Shehla; Rastogi, Neha; Dabas, Yubhisha

    2015-02-01

    This study aimed to evaluate the identification of clinical fungal isolates (yeast and molds) by protein profiling using Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS). A total of 125 clinical fungal culture isolates (yeast and filamentous fungi) were collected. The test set included 88 yeast isolates (Candida albicans, Candida glabrata, Candida guilliermondii, Candida kefyr, Candida krusei, Candida parapsilosis, Candida rugosa, Candida tropicalis and Cryptococcus neoformans) and 37 isolates of molds (Alternaria spp., Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Cunninghamella spp., Histoplasma capsulatum, Microsporum gypseum, Microsporum nanum, Rhizomucor spp. and Trichophyton spp.). The correlation between MALDI TOF MS and conventional identification for all these 125 fungal isolates included in the study was 87.2% at the species level and 90.4% at the genus level. MALDI TOF MS results revealed that the correlation in yeast (n=88) identification was 100% both at the genus and species levels whereas, the correlation in mold (n=37) identification was more heterogeneous i.e. 10.81% isolates had correct identification up to the genus level, 56.7% isolates had correct identification both at the genus and species levels, whereas 32.42% isolates were deemed Not Reliable Identification (NRI). But, with the modification in sample preparation protocol for molds, there was a significant improvement in identification. 86.4% isolates had correct identification till the genus and species levels whereas, only 2.7% isolates had Not Reliable Identification. In conclusion, this study demonstrates that MALDI-TOF MS could be a possible alternative to conventional techniques both for the identification and differentiation of clinical fungal isolates. However, the main limitation of this technique is that MS identification could be more precise only if the reference spectrum of the fungal species is available in the

  14. DNA transformations of Candida tropicalis with replicating and integrative vectors.

    Science.gov (United States)

    Sanglard, D; Fiechter, A

    1992-12-01

    The alkane-assimilating yeast Candida tropicalis was used as a host for DNA transformations. A stable ade2 mutant (Ha900) obtained by UV-mutagenesis was used as a recipient for different vectors carrying selectable markers. A first vector, pMK16, that was developed for the transformation of C. albicans and carries an ADE2 gene marker and a Candida autonomously replicating sequence (CARS) element promoting autonomous replication, was compatible for transforming Ha900. Two transformant types were observed: (i) pink transformants which easily lose pMK16 under non-selective growth conditions; (ii) white transformants, in which the same plasmid exhibited a higher mitotic stability. In both cases pMK16 could be rescued from these cells in Escherichia coli. A second vector, pADE2, containing the isolated C. tropicalis ADE2, gene, was used to transform Ha900. This vector integrated in the yeast genome at homologous sites of the ade2 locus. Different integration types were observed at one or both ade2 alleles in single or in tandem repeats.

  15. Influence of culture conditions for clinically isolated non-albicans Candida biofilm formation.

    Science.gov (United States)

    Tan, Yulong; Leonhard, Matthias; Ma, Su; Schneider-Stickler, Berit

    2016-11-01

    Non-albicans Candida species have been isolated in increasing numbers in patients. Moreover, they are adept at forming biofilms. This study analyzed biofilm formation of clinically isolated non-albicans Candida, including Candida tropicalis, Candida krusei and Candida parapsilosis under the influence of different growth media (RPMI 1640, YPD and BHI) and several culture variables (inoculum concentration, incubation period and feeding conditions). The results showed that culture conditions strongly influenced non-albicans Candida species biofilm formation. YPD and BHI resulted in larger amount of biofilm formation with higher metabolic activity of biofilms. Furthermore, the growth media seems to have varying effects on adhesion and biofilm development. Growth conditions may also influence biofilm formation, which was enhanced when starting the culture with a larger inoculum, longer incubation period and using a fed-batch system. Therefore, the potential influences of external environmental factors should be considered when studying the non-albicans Candida biofilms in vitro. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Acquired multi-azole resistance in Candida tropicalis during persistent urinary tract infection in a dog

    Directory of Open Access Journals (Sweden)

    Sergio Álvarez-Pérez

    2016-03-01

    Full Text Available Multi-azole resistance acquisition by Candida tropicalis after prolonged antifungal therapy in a dog with urinary candidiasis is reported. Pre- and post-azole treatment isolates were clonally related and had identical silent mutations in the ERG11 gene, but the latter displayed increased azole minimum inhibitory concentrations. A novel frameshift mutation in ERG3 was found in some isolates recovered after resistance development, so it appears unlikely that this mutation is responsible for multi-azole resistance.

  17. Clinical characterization of familial isolated pituitary adenomas

    NARCIS (Netherlands)

    A.F. Daly (Adrian); M-L. Jaffrain-Rea (Marie-Lise); E. Ciccarelli (Enrica); H. Valdes-Socin (H.); V. Rohmer (Vincent); G. Tamburrano (Guido); F. Borson-Chazot (Francoise); B. Estour (Bruno); E. Ciccarelli (Enrica); T. Brue (Thierry); P. Ferolla (Piero); P. Emy (Philippe); A. Colao (Annamaria); E. de Menis (Ernesto); P. Lecomte (Pierre); A. Penfornis (Alfred); B. Delemer (B.); J. Bertherat (Jerome); J.L. Wémeau; W.W. de Herder (Wouter); F. Archambeaud (Françoise); A. Stevenaert (A.); A. Calender (Alain); A. Murat (Arnaud); F. Cavagnini (Francesco); A. Beckers (Albert)

    2006-01-01

    textabstractContext: Familial pituitary adenomas occur rarely in the absence of multiple endocrine neoplasia type 1(MEN1)and Carney complex (CNC). Objective: Our objective was to characterize the clinical and genealogical features of non-MEN1/CNC familial isolated pituitary adenomas (FIPA). Design

  18. Increased cefepime MIC for enterobacteriacae clinical isolates.

    Science.gov (United States)

    Najafi, Narges; Alikhani, Ahmad; Babamahmoudi, Farhang; Davoudi, Alireza; Ghasemiyan, Roya; Aliyan, Shahriar; Shoujaiifar, Arman

    2013-01-01

    Background : Cefepime was used as empirical treatment in ventilator-associated pneumonia (VAP) induced by gram-negative and gram-positive bacteria. This study aimed to determine the antimicrobial susceptibility pattern of cefepime against microorganism causing VAP in Mazandaran, North of Iran. This study was performed on VAP patients diagnosed with clinical pulmonary infection score (CPIS) scores in ICU of two hospitals. For each patient suspected of having VAP, quantitative culture of endotracheal aspiration (QEA) was performed and MIC was determined by micro dilution test. Data were collected and analyzed. Thirty- five cases of enterobacteriaceae were isolated orderly including E coli 13, P. aeruginosa 11, Enterobacter 7 and K. pneumonia 4 cases. All the isolated E. coli, Enterobacter and Klebsiella, 54.5% of P. aeruginosa isolated were fully resistant to cefepime. The results of this study show that cefepime is not a reasonable choice for empirical treatment of nosocomial pneumonia and VAP.

  19. Antifungal susceptibility of bloodstream Candida isolates in Sfax hospital: Tunisia.

    Science.gov (United States)

    Sellami, A; Sellami, H; Néji, S; Makni, F; Abbes, S; Cheikhrouhou, F; Chelly, H; Bouaziz, M; Hammami, B; Ben Jemaa, M; Khaled, S; Ayadi, A

    2011-06-01

    Invasive candidiasis has emerged as an important nosocomial infection, causing significant morbidity and mortality especially among critically ill patients. The aim of our study was to determine specie distribution and resistance profiles of Candida species isolated from blood cultures. We conducted a retrospective study of all episodes of candidemia diagnosed in our laboratory from January 2006 to May 2009. The susceptibility to antifungal agents of all Candida isolates was tested by using a Sensititre(®) YeastOne panel. A total of 130 Candida isolates were recovered from blood cultures. Candida tropicalis was the most frequent specie (37.7%), followed by C. albicans (22.3%), C. glabrata (19.2%), and C. parapsilosis (12.2%). All the isolates were inhibited by ≤1 μg/ml of amphotericin B and ≤2 μg/ml of caspofungin. For fluconazole, 7.3% of clinical isolates were resistant. It was most active against C. parapsilosis (100% susceptible), C. albicans (95.8% susceptible), and C. tropicalis (94% susceptible). All of the fluconazole-susceptible isolates were susceptible to voriconazole, as were 83.3% of the fluconazole-susceptible-dose-dependent isolates. Among fluconazole-resistant isolates, 85.7% were susceptible to voriconazole. In our institution, C. tropicalis was the most frequent specie isolated from the bloodstream. Caspofungin had an excellent in vitro activity against Candida isolates and was the drug of choice among fluconazole-resistant isolates. © Springer Science+Business Media B.V. 2010

  20. Comparison of TALEN scaffolds in Xenopus tropicalis

    Directory of Open Access Journals (Sweden)

    Keisuke Nakajima

    2013-11-01

    Transcription activator-like effector nucleases (TALENs are facile and potent tools used to modify a gene of interest for targeted gene knockout. TALENs consist of an N-terminal domain, a DNA-binding domain, and a C-terminal domain, which are derived from a transcription activator-like effector, and the non-specific nuclease domain of FokI. Using Xenopus tropicalis (X. tropicalis, we compared the toxicities and somatic mutation activities of four TALEN architectures in a side-by-side manner: a basic TALEN, a scaffold with the same truncated N- and C-terminal domains as GoldyTALEN, a scaffold with the truncated N- and C-terminal domains and an obligate heterodimeric nuclease domain, and a scaffold with the truncated N- and C-terminal domains and an obligate heterodimeric Sharkey nuclease domain. The strongest phenotype and targeted somatic gene mutation were induced by the injection of TALEN mRNAs containing the truncated N- and C-terminal domains and an obligate heterodimeric nuclease domain. The obligate heterodimeric TALENs exhibited reduced toxicity compared to the homodimeric TALENs, and the homodimeric GoldyTALEN-type scaffold showed both a high activity of somatic gene modification and high toxicity. The Sharkey mutation in the heterodimeric nuclease domain reduced the TALEN-mediated somatic mutagenesis.

  1. Antifungal susceptibility of Candida species isolated from patients with candidemia in southern Taiwan, 2007-2012: impact of new antifungal breakpoints.

    Science.gov (United States)

    Chen, Yi-Chun; Kuo, Shu-Fang; Chen, Fang-Ju; Lee, Chen-Hsiang

    2017-02-01

    The Clinical and Laboratory Standard Institute (CLSI) revised the clinical breakpoints (CBPs) for the azoles and echinocandins against Candida species in 2012. We aimed to report the epidemiology of candidemia and antifungal susceptibility of Candida species and evaluate the impact of new CBPs on antifungal susceptibility in our region. All blood isolates of Candida species were obtained from 2007 to 2012. The minimum inhibitory concentrations of fluconazole, voriconazole, echinocandins and flucytosine against Candida isolates were determined by Sensititre YeastOne system. Differences in susceptibility rates between the CBPs of previous and revised versions of CLSI were examined. Of 709 Candida isolates, the fluconazole-susceptible rate was 96.5% in Candida albicans, 85.8% in Candida tropicalis and 92.1% in Candida parapsilosis by the revised CBPs. Compared with the susceptibility results by previous CBPs, the marked reductions in susceptibility of C. albicans, C. tropicalis and C. parapsilosis to fluconazole, that of C. tropicalis and C. parapsilosis to voriconazole, that of C. tropicalis and Candida glabrata to anidulafungin and that of C. tropicalis, C. glabrata and Candida krusei to caspofungin by revised CBPs were found. In conclusion, Candida albicans and C. parapsilosis remain highly susceptible to fluconazole. The non-susceptible rates of Candida species to azoles and echinocandins increase with interpretation by the revised CBPs. © 2016 Blackwell Verlag GmbH.

  2. Effects of fluconazole treatment of mice infected with fluconazole-susceptible and -resistant Candida tropicalis on fungal cell surface hydrophobicity, adhesion and biofilm formation

    Directory of Open Access Journals (Sweden)

    R L Kanoshiki

    2015-01-01

    Full Text Available Background : The incidence of Candida tropicalis less susceptible to fluconazole (FLC has been reported in many parts of the world. Objectives : The aim of this study was to examine the changes of putative virulence attributes of Candida tropicalis accompanying the development of resistance to FLC in vitro and in vivo. Materials and Methods : A FLC-resistant strain (FLC-R was obtained after sequential exposure of a clinical isolate FLC-sensitive (FLC-S to increasing concentrations of the antifungal. The course of infection by both strains was analyzed in BALB/c mice. Analyses of gene expression were performed by real-time polymerase chain reaction PCR. The cell surface hydrophobicity, adhesion and biofilm formation were also determined. Results : Development of resistance to FLC could be observed after 15 days of subculture in azole-containing medium. Overexpression of MDR1 and ERG11 genes were observed in FLC-R, and this strain exhibited enhanced virulence in mice, as assessed by the mortality rate. All mice challenged with the FLC-R died and FLC-treatment caused earlier death in mice infected with this strain. All animals challenged with FLC-S survived the experiment, regardless of FLC-treatment. Overall, FLC-R derivatives strains were significantly more hydrophobic than FLC-S strains and showed greater adherence and higher capacity to form biofilm on polystyrene surface. Conclusions : The expression of virulence factors was higher in FLC-R-C. tropicalis and it was enhanced after FLC-exposure. These data alert us to the importance of identifying microorganisms that show resistance to the antifungals to establish an appropriate management of candidiasis therapy.

  3. (ESBLs) among clinical Enterobacteriaceae isolates obtained from ...

    African Journals Online (AJOL)

    One hundred Gram negative bacterial isolates were collected from a private diagnostic center and identified by subjecting the isolates to biochemical tests using standard procedures. Confirmed Enterobacteriaceae isolates were further subjected to screening for extended spectrum â-lactamases (ESBLs) production using ...

  4. Characterization of Candida Species Isolated from cases of Vulvovaginitis in women referring to selected gynecological clinics

    Directory of Open Access Journals (Sweden)

    Batol Bonyadpour

    2016-10-01

    Full Text Available Background and aim: About 20% of non-pregnant women aged 15 to 55 harbour Candida albicans in the vagina .the aimed to determine the Characterization of Candida Species Isolated from women with Vulvovaginitis candidates (VVC of reproductive ages. Methods: this descriptive study was conducted on 280 of who were selected for gathering samples by Purposive sampling based on their history and characteristics of vaginal discharges in 2009. Among these patients, 105 ones were diagnosed with candidiasis. The data were collected using demographic information form and disease symptoms. the species were differentiated using germ tube test, chrome agar test, and chlamidospore test. Data analysis was performed in SPSS V.16, using Descriptive Statistics Results: the prevalence of candida vaginitis was 9.3%.105 samples obtained from patients.. Chlamidospore was detected in 54.3% of the corn meal agar media. Besides, in chrome agar test, 41.9% of the samples turned into green representing candida albicans. In germ tube test, on the other hand, 70.5% of the samples were candida albicans, while 29.5% were candida non-albicans. Overall, The frequency of the Candida albicans, Candida glabrata, Candida tropicalis and  the Candida Krusei were  66.6% , 219%  , 8.6% ,  and 2.9%, respectively. Conclusion: Candida albicans was the most common species leading to the Vulvovaginitis in patients with VCC while other species were at the secondary importance stages.Due to inaccurate diagnosis of the disease based on the clinical symptoms, fungal culture is recommended as a standard diagnostic method.

  5. Furfural tolerance and detoxification mechanism inCandida tropicalis.

    Science.gov (United States)

    Wang, Shizeng; Cheng, Gang; Joshua, Chijioke; He, Zijun; Sun, Xinxiao; Li, Ruimin; Liu, Lexuan; Yuan, Qipeng

    2016-01-01

    Current biomass pretreatment by hydrothermal treatment (including acid hydrolysis, steam explosion, and high-temperature steaming) and ionic liquids generally generate inhibitors to the following fermentation process. Furfural is one of the typical inhibitors generated in hydrothermal treatment of biomass. Furfural could inhibit cell growth rate and decrease biofuel productivity of microbes. Candida tropicalis is a promising microbe for the production of biofuels and value-added chemicals using hemicellulose hydrolysate as carbon source. In this study, C. tropicalis showed a comparable ability of furfural tolerance during fermentation. We investigated the mechanism of C. tropicalis 's robust tolerance to furfural and relevant metabolic responses to obtain more information for metabolic engineering of microbes for efficient lignocellulose fermentation. Candida tropicalis showed comparable intrinsic tolerance to furfural and a fast rate of furfural detoxification. C. tropicalis 's half maximal inhibitory concentration for furfural with xylose as the sole carbon source was 3.69 g/L, which was higher than that of most wild-type microbes reported in the literature to our knowledge. Even though furfural prolonged the lag phase of C. tropicalis , the final biomass in the groups treated with 1 g/L furfural was slightly greater than that in the control groups. By real-time PCR analysis, we found that the expression of ADH1 in C. tropicalis ( ctADH1 ) was induced by furfural and repressed by ethanol after furfural depletion. The expression of ctADH1 could be regulated by both furfural and ethanol. After the disruption of gene ctADH1 , we found that C. tropicalis 's furfural tolerance was weakened. To further confirm the function of ctADH1 and enhance Escherichia coli 's furfural tolerance, ctADH1 was overexpressed in E. coli BL21 (DE3). The rate of furfural degradation in E. coli BL21 (DE3) with pET-ADH1 (high-copy plasmid) and pCS-ADH1 (medium-copy plasmid) was increased

  6. Detection of efflux pump activity among clinical isolates of ...

    African Journals Online (AJOL)

    Detection of efflux pump activity among clinical isolates of. Staphylococcus and Micrococcus ... Philadelphia, USA, 3Department of Medical Laboratory Science, College of Medicine, University of Lagos, Lagos, Nigeria. *For correspondence: Email: ... Eighteen clinical isolates comprising of 14 S. aureus, 2 S. lentus, 1 S.

  7. Ribosomal resistance of clinical enterococcal to streptomycin isolates.

    OpenAIRE

    Eliopoulos, G M; Farber, B F; Murray, B E; Wennersten, C; Moellering, R C

    1984-01-01

    The mechanism of high-level resistance to streptomycin was studied in 12 clinical isolates of Streptococcus faecalis. Six strains produced streptomycin-modifying enzymes. Each of three enzyme-negative strains tested demonstrated ribosomal resistance to streptomycin. Lack of ribosomal susceptibility is a significant cause of high-level streptomycin resistance among clinical enterococcal isolates.

  8. Specific Gene Loci of Clinical Pseudomonas putida Isolates

    Science.gov (United States)

    Molina, Lázaro; Udaondo, Zulema; Duque, Estrella; Fernández, Matilde; Bernal, Patricia; Roca, Amalia; de la Torre, Jesús; Ramos, Juan Luis

    2016-01-01

    Pseudomonas putida are ubiquitous inhabitants of soils and clinical isolates of this species have been seldom described. Clinical isolates show significant variability in their ability to cause damage to hosts because some of them are able to modulate the host’s immune response. In the current study, comparisons between the genomes of different clinical and environmental strains of P. putida were done to identify genetic clusters shared by clinical isolates that are not present in environmental isolates. We show that in clinical strains specific genes are mostly present on transposons, and that this set of genes exhibit high identity with genes found in pathogens and opportunistic pathogens. The set of genes prevalent in P. putida clinical isolates, and absent in environmental isolates, are related with survival under oxidative stress conditions, resistance against biocides, amino acid metabolism and toxin/antitoxin (TA) systems. This set of functions have influence in colonization and survival within human tissues, since they avoid host immune response or enhance stress resistance. An in depth bioinformatic analysis was also carried out to identify genetic clusters that are exclusive to each of the clinical isolates and that correlate with phenotypical differences between them, a secretion system type III-like was found in one of these clinical strains, a determinant of pathogenicity in Gram-negative bacteria. PMID:26820467

  9. Specific Gene Loci of Clinical Pseudomonas putida Isolates.

    Directory of Open Access Journals (Sweden)

    Lázaro Molina

    Full Text Available Pseudomonas putida are ubiquitous inhabitants of soils and clinical isolates of this species have been seldom described. Clinical isolates show significant variability in their ability to cause damage to hosts because some of them are able to modulate the host's immune response. In the current study, comparisons between the genomes of different clinical and environmental strains of P. putida were done to identify genetic clusters shared by clinical isolates that are not present in environmental isolates. We show that in clinical strains specific genes are mostly present on transposons, and that this set of genes exhibit high identity with genes found in pathogens and opportunistic pathogens. The set of genes prevalent in P. putida clinical isolates, and absent in environmental isolates, are related with survival under oxidative stress conditions, resistance against biocides, amino acid metabolism and toxin/antitoxin (TA systems. This set of functions have influence in colonization and survival within human tissues, since they avoid host immune response or enhance stress resistance. An in depth bioinformatic analysis was also carried out to identify genetic clusters that are exclusive to each of the clinical isolates and that correlate with phenotypical differences between them, a secretion system type III-like was found in one of these clinical strains, a determinant of pathogenicity in Gram-negative bacteria.

  10. Biodegradation of crude petroleum oil and environmental pollutants by Candida tropicalis strain

    Energy Technology Data Exchange (ETDEWEB)

    Farag, Soha [Mubarak City for Scientific Research and Technology Applications, Alexandria (Egypt). Genetic Engineering Biotechnology Research Institute. Environmental Biotechnology Dept.; Soliman, Nadia A. [Mubarak City for Scientific Research and Technology Applications, Alexandria (Egypt). Genetic Engineering Biotechnology Research Institute. Bioprocess Development Dept.

    2011-07-15

    A local yeast isolate named A was isolated from polluted area of Abou-Qir gulf (Alexandria, Egypt), identified according to a partial sequence of 18sRNA as Candida tropicalis. The isolate showed a high potency in petroleum oil biodegradation as well some hydrocarbons. Morphological changes in cell diameter of this yeast were recognized upon growing the target cell in sea water medium supplemented with petroleum oil as sole carbon source in comparison to the growth in enriched medium. Statistically-based experimental design was applied to evaluate the significance of factors on petroleum oil biodegradation by this yeast isolate. Eleven culture conditions were examined by implementing Plackett-Burman factorial design where aeration, NH{sub 4}Cl and K{sub 2}HPO{sub 4} had the most positive significance on oil degradation. (author)

  11. Biodegradation of crude petroleum oil and environmental pollutants by Candida tropicalis strain

    Directory of Open Access Journals (Sweden)

    Soha Farag

    2011-08-01

    Full Text Available A local yeast isolate named A was isolated from polluted area of Abou-Qir gulf (Alexandria, Egypt, identified according to a partial sequence of 18sRNA as Candida tropicalis. The isolate showed a high potency in petroleum oil biodegradation as well some hydrocarbons. Morphological changes in cell diameter of this yeast were recognized upon growing the target cell in sea water medium supplemented with petroleum oil as sole carbon source in comparison to the growth in enriched medium. Statistically-based experimental design was applied to evaluate the significance of factors on petroleum oil biodegradation by this yeast isolate. Eleven culture conditions were examined by implementing Plackett-Burman factorial design where aeration, NH4Cl and K2HPO4 had the most positive significance on oil degradation.

  12. Species distribution and in vitro fluconazole susceptibility of clinical Candida isolates in a Brazilian tertiary-care hospital over a 3-year period

    Directory of Open Access Journals (Sweden)

    Márcia Cristina Furlaneto

    2011-10-01

    Full Text Available INTRODUCTION: In this study, we aimed at identifying Candida isolates obtained from blood, urine, tracheal secretion, and nail/skin lesions from cases attended at the Hospital Universitário de Londrina over a 3-year period and at evaluating fluconazole susceptibilities of the isolates. METHODS: Candida isolates were identified by polymerase chain reaction (PCR using species-specific forward primers. The in vitro fluconazole susceptibility test was performed according to EUCAST-AFST reference procedure. RESULTS: Isolates were obtained from urine (53.4%, blood cultures (19.2%, tracheal secretion (17.8%, and nail/skin lesions (9.6%. When urine samples were considered, prevalence was similar in women (45.5% and in men (54.5% and was high in the age group >61 years than that in younger ones. For blood samples, prevalence was high in neonates (35% and advanced ages (22.5%. For nail and skin samples, prevalence was higher in women (71.4% than in men (28.6%. Candida albicans was the most frequently isolated in the hospital, but Candida species other than C. albicans accounted for 64% of isolates, including predominantly Candida tropicalis (33.2% and Candida parapsilosis (19.2%. The trend for non-albicans Candida as the predominant species was noted from all clinical specimens, except from urine samples. All Candida isolates were considered susceptible in vitro to fluconazole with the exception of isolates belonging to the intrinsically less-susceptible species C. glabrata. CONCLUSIONS: Non-albicans Candida species were more frequently isolated in the hospital. Fluconazole resistance was a rare finding in our study.

  13. Identification of Candida tropicalis BH-6 and synergistic effect with Pantoea agglomerans BH-18 on hydrogen production in marine culture.

    Science.gov (United States)

    Zhu, Daling; Ma, Yingchao; Wang, Guangce; Pan, Guanghua

    2015-03-01

    A marine yeast was isolated from mangrove sludge and named Candida tropicalis BH-6. The optimum temperature and the initial pH value for growth of the isolated strain were 37 °C and 5.0, respectively. The strain had high salt tolerance and could survive at NaCl concentrations of 0-6 %. Additionally, the yield of hydrogen production by C. tropicalis BH-6 was only 66.30 ml/l. However, when the yeast was mixed with Pantoea agglomerans BH-18, hydrogen production increased significantly to a maximum of 1707.5 ml/l, which was 36.94 and 247.54 % higher than the monoculture of P. agglomerans BH-18 and C. tropicalis BH-6, respectively. Taken together, these results revealed that in mixed culture, the yeast strain isolated from the same ecosystem as P. agglomerans BH-18 likely consumed the organic acids produced by fermentation, thus eliminating the factor inhibiting hydrogen production by P. agglomerans BH-18. As a result, the yield of hydrogen production during mixed culture increased significantly.

  14. The genome of the Western clawed frog Xenopus tropicalis.

    Science.gov (United States)

    Hellsten, Uffe; Harland, Richard M; Gilchrist, Michael J; Hendrix, David; Jurka, Jerzy; Kapitonov, Vladimir; Ovcharenko, Ivan; Putnam, Nicholas H; Shu, Shengqiang; Taher, Leila; Blitz, Ira L; Blumberg, Bruce; Dichmann, Darwin S; Dubchak, Inna; Amaya, Enrique; Detter, John C; Fletcher, Russell; Gerhard, Daniela S; Goodstein, David; Graves, Tina; Grigoriev, Igor V; Grimwood, Jane; Kawashima, Takeshi; Lindquist, Erika; Lucas, Susan M; Mead, Paul E; Mitros, Therese; Ogino, Hajime; Ohta, Yuko; Poliakov, Alexander V; Pollet, Nicolas; Robert, Jacques; Salamov, Asaf; Sater, Amy K; Schmutz, Jeremy; Terry, Astrid; Vize, Peter D; Warren, Wesley C; Wells, Dan; Wills, Andrea; Wilson, Richard K; Zimmerman, Lyle B; Zorn, Aaron M; Grainger, Robert; Grammer, Timothy; Khokha, Mustafa K; Richardson, Paul M; Rokhsar, Daniel S

    2010-04-30

    The western clawed frog Xenopus tropicalis is an important model for vertebrate development that combines experimental advantages of the African clawed frog Xenopus laevis with more tractable genetics. Here we present a draft genome sequence assembly of X. tropicalis. This genome encodes more than 20,000 protein-coding genes, including orthologs of at least 1700 human disease genes. Over 1 million expressed sequence tags validated the annotation. More than one-third of the genome consists of transposable elements, with unusually prevalent DNA transposons. Like that of other tetrapods, the genome of X. tropicalis contains gene deserts enriched for conserved noncoding elements. The genome exhibits substantial shared synteny with human and chicken over major parts of large chromosomes, broken by lineage-specific chromosome fusions and fissions, mainly in the mammalian lineage.

  15. Sensitivity pattern of clinical isolates of Candida albicans from hiv ...

    African Journals Online (AJOL)

    This study was carried out to investigate the sensitivity pattern of clinical isolates of C. albicans from HIV/AIDS patients to combined P. grisea extract and tioconazole. Twenty isolates of C. albicans were obtained from high vaginal swab (HVS) from HIV/AIDS patients in Bishop Shanahan Hospital, Nsukka after their ...

  16. Detection of Polish clinical Aspergillus fumigatus isolates resistant to triazoles

    DEFF Research Database (Denmark)

    Nawrot, Urszula; Kurzyk, Ewelina; Arendrup, Maiken Cavling

    2018-01-01

    We studied the presence of triazole resistance of 121 Aspergillus fumigatus clinical isolates collected in two Polish cities, Warsaw and Wrocław, to determine if resistance is emerging in our country. We identified five itraconazole resistant isolates (4.13%) carrying the TR34/L98H alteration in ...

  17. Detection of Amp C Beta Lactamases in Clinical Isolates of ...

    African Journals Online (AJOL)

    A total of 81 consecutive non repetitive clinical isolates of Escherichia coli (n=40) and Klebsiella spp. (n=41) were screened for AmpC production by disc diffusion method using cefoxitin (30 Zg) disc and confirmed by inhibitor based test using boronic acid as inhibitor. A total of 16 E.coli isolates (40%) and 16 Klebsiella ...

  18. Evaluation of Genetic Diversity of Candida spp. and Klebsiella spp. Isolated from the Denture Plaque of COPD Patients.

    Science.gov (United States)

    Przybyłowska, D; Piskorska, K; Gołaś, M; Sikora, M; Swoboda-Kopeć, E; Kostrzewa-Janicka, J; Mierzwińska-Nastalska, E

    2017-01-01

    Yeast-like fungi and gram-negative bacilli are the most frequent potential pathogens of the respiratory tract isolated from the denture plaque of patients with chronic obstructive pulmonary disease (COPD). Dominant species among yeast-like fungi are Candida albicans and Candida tropicalis. Significant frequency is also exhibited by Klebsiella pneumoniae and Klebsiella oxytoca. The purpose of this study was to analyze genetic diversity of the strains of C. albicans, C. tropicalis, and Klebsiella spp. present in patients in stable phases of COPD. The analysis was conducted by the random amplified polymorphic DNA (RAPD) method on clinical strains isolated from patients with COPD and control patients in overall good health. Forty one strains of Candida albicans, 12 of Candida tropicalis, as well as 9 strains of K. pneumoniae and 7 of K. oxytoca were scrutinized. The dominant species in clinical material from COPD patients was Candida albicans with a substantial degree of variations of genetic profiles. On the basis of affinity analysis, 19 genetic types were identified within this strain. An analysis of the banding patterns among C. tropicalis strains indicated the existence of 6 genetic types. A considerable diversity of genetic profiles among Klebsiella spp. also was established. The genotype diversity of Klebsiella spp. strains may indicate the endogenic character of the majority of infections, regardless of the therapy applied for the underlying condition.

  19. Epidemiological Studies on Proteeae Isolates from Clinical ...

    African Journals Online (AJOL)

    Specimens were collected from patients and screened for Proteeae using standard microbiological and biochemical methods (API 20 Enterobacteriaceae gallery). Of the 3414 clinical specimens made of 2712 urine, 264 blood, 243 CSF and 195 wounds and burns, 1136 (33.3%) yielded a positive bacterial growth, of which ...

  20. Candida albicans isolates from a Malaysian hospital exhibit more potent phospholipase and haemolysin activities than non-albicans Candida isolates.

    Science.gov (United States)

    Chin, V K; Foong, K J; Maha, A; Rusliza, B; Norhafizah, M; Ng, K P; Chong, P P

    2013-12-01

    This study was aimed at determining the phospholipase and haemolysin activity of Candida isolates in Malaysia. A total of 37 Candida clinical isolates representing seven species, Candida albicans (12), Candida tropicalis (8), Candida glabrata (4), Candida parapsilosis (1), Candida krusei (4), Candida orthopsilosis (1) and Candida rugosa (7) were tested. In vitro phospholipase activity was determined by using egg yolk plate assay whereas in vitro haemolysin activity was tested by using blood plate assay on sheep blood Sabouraud's dextrose agar (SDA) enriched with glucose. Phospholipase activity was detected in 75% (9 out of 12) of the C. albicans isolates. Among the 25 non- C. albicans Candida isolates, phospholipase activity was detected in only 24% of these isolates. The phospholipase activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.002). Haemolysin activity was detected in 100% of the C. albicans, C. tropicalis, C. glabrata, C. krusei, C. parapsilosis, and C. orthopsilosis isolates while 75% of the C. krusei isolates and 12.3% of the C. rugosa isolates showed haemolysin activity. The haemolytic activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.0001).The findings in this study indicate that C. albicans isolates in Malaysia may possess greater virulence potential than the non-albicans species.

  1. Helminth parasites of Silurana tropicalis from the Okomu National ...

    African Journals Online (AJOL)

    Silurana tropicalis, the edible clawed-frog, collected from the Okomu National Park, Edo State, Nigeria, was examined for helminth parasitic infections. From 142 specimens collected, ten endo-helminth parasites spread across four classes were recovered. These included Cestoda: Cephalochlamys compactus and the cyst ...

  2. Reproductive Maturation of the Tropical Clawed Frog, Xenopus tropicalis

    Science.gov (United States)

    The model species Xenopus tropicalis is being widely used in developmental biology and amphibian toxicology studies. In order to increase our understanding of the role of steroid hormones in maturation in this species, we collected baseline reproductive data from metamorphosis t...

  3. Xylitol production by Candida tropicalis under different statistically ...

    African Journals Online (AJOL)

    Nutritional and environmental conditions of the xylose utilizing yeast Candida tropicalis were optimized on a shake-flask scale using a statistical factorial design to maximize the production of xylitol. Effects of the three growth medium components (rice bran, ammonium sulfate and xylose) on the xylitol production were ...

  4. Proteogenomic Investigation of Strain Variation in Clinical Mycobacterium tuberculosis Isolates

    KAUST Repository

    Heunis, Tiaan

    2017-08-18

    Mycobacterium tuberculosis consists of a large number of different strains that display unique virulence characteristics. Whole-genome sequencing has revealed substantial genetic diversity among clinical M. tuberculosis isolates, and elucidating the phenotypic variation encoded by this genetic diversity will be of utmost importance to fully understand M. tuberculosis biology and pathogenicity. In this study we integrated whole-genome sequencing and mass spectrometry (GeLC-MS/MS) to reveal strain-specific characteristics in the proteomes of two clinical M. tuberculosis Latin American-Mediterranean isolates. Using this approach we identified 59 peptides containing single amino acid variants, which covered ~9% of all total coding nonsynonymous single nucleotide variants detected by whole-genome sequencing. Furthermore, we identified 29 distinct peptides that mapped to a hypothetical protein not present in the M. tuberculosis H37Rv reference proteome. Here we provide evidence for the expression of this protein in the clinical M. tuberculosis SAWC3651 isolate. The strain-specific databases enabled confirmation of genomic differences (i.e. large genomic regions of difference and nonsynonymous single nucleotide variants) in these two clinical M. tuberculosis isolates and allowed strain differentiation at the proteome level. Our results contribute to the growing field of clinical microbial proteogenomics and can improve our understanding of phenotypic variation in clinical M. tuberculosis isolates.

  5. Quinolones Resistance And R-Plasmids Of Clinical Isolates Of ...

    African Journals Online (AJOL)

    Background: There has been reported incidence in the emergence of. Quinolones resistance in clinical isolates in Nigeria and the level in resistance has been on the increase. Objective: To determine the antimicrobial resistance patterns and plasmids profiles of 67 clinical Pseudomonas species from a teaching hospital ...

  6. Isolation and characterization of Marine fungal metabolites against clinical pathogens

    Directory of Open Access Journals (Sweden)

    Rajasekar T

    2012-05-01

    Full Text Available Objective: To isolate and identify of marine fungal metabolites against clinical bacterial pathogens. To optimize the production medium for isolated fungus. Method: Marine fungus isolated from water and sediment samples from different places of Sundarbans mangrove, Muttukadu (Chennai and Parangipettai in India. Antimicrobial substance from marine fungi was produced by agar plate method. The potent fungal were inoculated on production medium and extracted was done. The extracted compound was checked for anti bacterial activity. Suitable production medium were optimized. Result: Totally 30 fungal isolates were recovered and morphologically 10 different strains were belongs to the fungal genera such as Fusarium, Aspergillus, Mucor and Penicillium. Preliminary screening results showed 3 fungal isolates showed promising activity. After production of potent fungal SS2 crude extracts showed highest inhibition against the bacterial pathogens out of 3 fungal isolates. The results showed maximum zone in 20mm against E.coli and minimum 10 mm against Vibrio sp. Conclusions: The present study identified Fusarium sp isolated from Sundarbans mangrove water as a potential source for bioactive compounds. Further isolation of active compound from potential fungal isolates will leads to the discovery of effective antimicrobials.

  7. Epidemiology, Clinical Characteristics, and Antimicrobial Susceptibility Profiles of Human Clinical Isolates of Staphylococcus intermedius Group.

    Science.gov (United States)

    Yarbrough, Melanie L; Lainhart, William; Burnham, C A

    2018-03-01

    The veterinary pathogens in the Staphylococcus intermedius group (SIG) are increasingly recognized as causes of human infection. Shared features between SIG and Staphylococcus aureus may result in the misidentification of SIG in human clinical cultures. This study examined the clinical and microbiological characteristics of isolates recovered at a tertiary-care academic medical center. From 2013 to 2015, 81 SIG isolates were recovered from 62 patients. Patients were commonly ≥50 years old, diabetic, and/or immunocompromised. Documentation of dog exposure in the electronic medical record was not common. Of the 81 SIG isolates, common sites of isolation included 37 (46%) isolates from wound cultures and 17 (21%) isolates from respiratory specimens. Although less common, 10 (12%) bloodstream infections were documented in 7 unique patients. The majority of SIG (65%) isolates were obtained from polymicrobial cultures. In comparison to S. aureus isolates from the same time period, significant differences were noted in proportion of SIG isolates that were susceptible to doxycycline (74% versus 97%, respectively; P SIG isolates. All MR isolates detected by an oxacillin disk diffusion test would have been misclassified as methicillin susceptible using a cefoxitin disk diffusion test. Thus, SIG is recovered from human clinical specimens, and distinction of SIG from S. aureus is critical for the accurate characterization of MR status in these isolates. Copyright © 2018 American Society for Microbiology.

  8. Antibiotic resistance among Helicobacter pylori clinical isolates in Lima, Peru.

    Science.gov (United States)

    Boehnke, Kevin F; Valdivieso, Manuel; Bussalleu, Alejandro; Sexton, Rachael; Thompson, Kathryn C; Osorio, Soledad; Novoa Reyes, Italo; Crowley, John J; Baker, Laurence H; Xi, Chuanwu

    2017-01-01

    Gastric carcinoma is the most common cancer and cause of cancer mortality in Peru. Helicobacter pylori , a bacterium that colonizes the human stomach, is a Group 1 carcinogen due to its causal relationship to gastric carcinoma. While eradication of H. pylori can help prevent gastric cancer, characterizing regional antibiotic resistance patterns is necessary to determine targeted treatment for each region. Thus, we examined primary antibiotic resistance in clinical isolates of H. pylori in Lima, Peru. H. pylori strains were isolated from gastric biopsies of patients with histologically proven H. pylori infection. Primary antibiotic resistance among isolates was examined using E-test strips. Isolates were examined for the presence of the cagA pathogenicity island and the vacA m1/m2 alleles via polymerase chain reaction. Seventy-six isolates were recovered from gastric biopsies. Clinical isolates showed evidence of antibiotic resistance to 1 (27.6%, n=21/76), 2 (28.9%, n=22/76), or ≥3 antibiotics (40.8%). Of 76 isolates, eight (10.5%) were resistant to amoxicillin and clarithromycin, which are part of the standard triple therapy for H. pylori infection. No trends were seen between the presence of cagA , vacA m1, or vacA m2 and antibiotic resistance. The rate of antibiotic resistance among H. pylori isolates in Lima, Peru, is higher than expected and presents cause for concern. To develop more targeted eradication therapies for H. pylori in Peru, more research is needed to better characterize antibiotic resistance among a larger number of clinical isolates prospectively.

  9. Antibiotic resistance among Helicobacter pylori clinical isolates in Lima, Peru

    Science.gov (United States)

    Boehnke, Kevin F; Valdivieso, Manuel; Bussalleu, Alejandro; Sexton, Rachael; Thompson, Kathryn C; Osorio, Soledad; Reyes, Italo Novoa; Crowley, John J; Baker, Laurence H; Xi, Chuanwu

    2017-01-01

    Objectives Gastric carcinoma is the most common cancer and cause of cancer mortality in Peru. Helicobacter pylori, a bacterium that colonizes the human stomach, is a Group 1 carcinogen due to its causal relationship to gastric carcinoma. While eradication of H. pylori can help prevent gastric cancer, characterizing regional antibiotic resistance patterns is necessary to determine targeted treatment for each region. Thus, we examined primary antibiotic resistance in clinical isolates of H. pylori in Lima, Peru. Materials and methods H. pylori strains were isolated from gastric biopsies of patients with histologically proven H. pylori infection. Primary antibiotic resistance among isolates was examined using E-test strips. Isolates were examined for the presence of the cagA pathogenicity island and the vacA m1/m2 alleles via polymerase chain reaction. Results Seventy-six isolates were recovered from gastric biopsies. Clinical isolates showed evidence of antibiotic resistance to 1 (27.6%, n=21/76), 2 (28.9%, n=22/76), or ≥3 antibiotics (40.8%). Of 76 isolates, eight (10.5%) were resistant to amoxicillin and clarithromycin, which are part of the standard triple therapy for H. pylori infection. No trends were seen between the presence of cagA, vacA m1, or vacA m2 and antibiotic resistance. Conclusion The rate of antibiotic resistance among H. pylori isolates in Lima, Peru, is higher than expected and presents cause for concern. To develop more targeted eradication therapies for H. pylori in Peru, more research is needed to better characterize antibiotic resistance among a larger number of clinical isolates prospectively. PMID:28331349

  10. Fusidic acid resistance among staphylococci strains isolated from clinical specimens

    Directory of Open Access Journals (Sweden)

    Özcan Deveci

    2012-03-01

    Full Text Available Objectives: The aim of this study was to investigate in vitrosusceptibility of fusidic acid to clinic isolates of staphylococci.Materials and methods: The forty-one coagulase negativestaphylococci (CNS and 18 Staphylococcus aureusstrains isolated from various clinical specimens were includedin this study. Staphylococci isolates were identifiedby conventional methods such as colony morphologyonto medium, gram staining, catalase and coagulasetests. According to “Clinical and Laboratory Standards Institute(CLSI” criteria, antimicrobial susceptibility testingof isolates was performed by Kirby-Bauer’s disk diffusionmethod.Results: The seventy-two percent of the isolated S.aureuswere defined as methicillin sensitive-S.aureus (MSSA,28% of the isolated S.aureus were defined as methicillinresistant-S.aureus (MRSA. The difference among fusidicacid susceptibility rates of MSSA and MRSA strains wasnot statistically significant (p=0.305. The twenty-nine percentof the isolated CNS were defined as methicillin sensitive-CNS (MS-CNS, 71% of the isolated CNS were definedas methicillin resistant-CNS (MR-CNS. There wasno statistically significant difference between MS-CNSand MR-CNS strains for fusidic acid susceptibility rates(p=0.490. But the difference among fusidic acid susceptibilityrates of CNS and S.aureus strains was statisticallysignificant (p<0.001. CNS strains were found more resistancethan S.aureus strains for fusidic acid.Conclusion: In this study, the resistance rates weredetected to increase for fusidic acid along with methicillinresistance. Among CNS isolates, fusidic acid resistancerates were significantly more elevated than that forS.aureus. Fusidic acid remains as an alternative in thetreatment of infections due to staphylococci.

  11. Insertional Mutagenesis for Genes involved in Otic/Vestibular Development and Function in Xenopus Tropicalis

    Science.gov (United States)

    Torrejon, Marcela; Li, Erica; Nguyen, Minh; Winfree, Seth; Wang, Esther; Reinsch, Sigrid; Dalton, Bonnie (Technical Monitor)

    2002-01-01

    Sensitivity to gravity is essential for spatial orientation. Consequently, the gravity receptor system is one of the phylogenetically oldest sensory systems, and the special adaptations that enhance sensitivity to gravity are highly conserved. The main goal of this project is to use Xenopus (frog) to identify genes expressed during vestibular and auditory development. These studies will lead a better understanding of the molecular mechanisms involved in vestibular and auditory development and function. We are using a gene-trap approach in Xenopus tropicalis with the green fluorescent protein (GFP) gene as the transgene reporter. GFP expression occurs only when the GFP gene is correctly integrated in actively transcribed genes. Using the GFP as a tag we can easily identify and clone the mutated gene. In addition, we can study the function of the mutated gene by analyzing the defects generated by insertion of the GFP transgene. To date we have tissue specific GFP expression in X. tropicalis including expression in ear, neural tube, kidney, muscle, eyes and nose. Our transgenic animals will soon reach maturity so that we can outcross them and analyze their progeny. Our next goal is to isolate RNA from our transgenics and clone the tagged genes using RACE-PCR. Currently we are optimizing the RACE-PCR method using transgenics with crystallin GFP expression.

  12. Molecular mechanism of fluoroquinolones resistance in Mycoplasma hominis clinical isolates

    Directory of Open Access Journals (Sweden)

    Meng Dong-Ya

    2014-01-01

    Full Text Available To evaluate the molecular mechanism of fluoroquinolones resistance in Mycoplasma hominis (MH clinical strains isolated from urogenital specimens. 15 MH clinical isolates with different phenotypes of resistance to fluoroquinolones antibiotics were screened for mutations in the quinolone resistance-determining regions (QRDRs of DNA gyrase (gyrA and gyrB and topoisomerase IV (parC and parE in comparison with the reference strain PG21, which is susceptible to fluoroquinolones antibiotics. 15 MH isolates with three kinds of quinolone resistance phenotypes were obtained. Thirteen out of these quinolone-resistant isolates were found to carry nucleotide substitutions in either gyrA or parC. There were no alterations in gyrB and no mutations were found in the isolates with a phenotype of resistance to Ofloxacin (OFX, intermediate resistant to Levofloxacin (LVX and Sparfloxacin (SFX, and those susceptible to all three tested antibiotics. The molecular mechanism of fluoroquinolone resistance in clinical isolates of MH was reported in this study. The single amino acid mutation in ParC of MH may relate to the resistance to OFX and LVX and the high-level resistance to fluoroquinolones for MH is likely associated with mutations in both DNA gyrase and the ParC subunit of topoisomerase IV.

  13. Molecular mechanism of fluoroquinolones resistance in Mycoplasma hominis clinical isolates.

    Science.gov (United States)

    Meng, Dong-Ya; Sun, Chang-Jian; Yu, Jing-Bo; Ma, Jun; Xue, Wen-Cheng

    2014-01-01

    To evaluate the molecular mechanism of fluoroquinolones resistance in Mycoplasma hominis (MH) clinical strains isolated from urogenital specimens. 15 MH clinical isolates with different phenotypes of resistance to fluoroquinolones antibiotics were screened for mutations in the quinolone resistance-determining regions (QRDRs) of DNA gyrase (gyrA and gyrB) and topoisomerase IV (parC and parE) in comparison with the reference strain PG21, which is susceptible to fluoroquinolones antibiotics. 15 MH isolates with three kinds of quinolone resistance phenotypes were obtained. Thirteen out of these quinolone-resistant isolates were found to carry nucleotide substitutions in either gyrA or parC. There were no alterations in gyrB and no mutations were found in the isolates with a phenotype of resistance to Ofloxacin (OFX), intermediate resistant to Levofloxacin (LVX) and Sparfloxacin (SFX), and those susceptible to all three tested antibiotics. The molecular mechanism of fluoroquinolone resistance in clinical isolates of MH was reported in this study. The single amino acid mutation in ParC of MH may relate to the resistance to OFX and LVX and the high-level resistance to fluoroquinolones for MH is likely associated with mutations in both DNA gyrase and the ParC subunit of topoisomerase IV.

  14. [Adhesion of clinical Candida albicans isolate to buccal epithelial cells].

    Science.gov (United States)

    Wellmer, A

    1999-01-01

    Mucosal adherence and germ tube formation are considered to be important virulence factors of C. albicans. Adherence is a precondition for colonisation and invasion. We investigated 11 clinical isolates (among them 5 cases recovered from oesophageal thrush) for quantification of the two characteristics and correlated the results with clinical data. Adherence was measured on buccal epithelial cells and the continuous flow culture was used for quantification of germ tube formation. Adherence of strains recovered from clinically, culturally and serologically confirmed oesophageal thrush adhered stronger to buccal epithelial cells than isolates from patients with heavy colonisation without signs of candidosis. Strains with stronger adherence showed a significantly faster and an increased germ tube formation in the continuous flow culture. Strains from oesophageal thrush therefore show a more marked expression of the investigated virulence factors. Therefore a good adherence is a necessity for infection of the oesophagus by C. albicans. The preferential isolation of C. albicans from oesophageal thrush (> 90%) supports this assumption.

  15. [Blomia tropicalis is found in a flour warehouse of a food factory in a civil aviation airport].

    Science.gov (United States)

    Ning, T; Shao-Sheng, W; Yan-Feng, Y; Yong, Z; Chao-Pin, L I

    2017-04-28

    Objective To investigate whether there is Blomia tropicalis breeding in the flour warehouse of food factory in a civil aviation airport, and, if there is, to observe the morphological structure of the mite. Methods The flour samples were collected from the flour warehouse of food factory in a civil aviation airport. The breeding mites were isolated from the samples by direct microscopy and made into specimens to observe with a light microscope. Results Female Blomia tropicalis was found in the collected flour samples. Under the microscope, the mite was nearly spherical, and it had no tergum and claw. Its apodemeⅠ was developed and connected in the midline. The reproductive hole was located between the foot Ⅲ and IV level and was covered with a pair of oblique genital folds. The foot Ⅲ and Ⅳ had no solenoids. The copulatory pouch was a long, slightly curved tube, extending from the end of the mite. Conclusions Blomia tropicalis has been found in the flour warehouse of a food factory in the civil aviation airport. The main distinguishing feature of this mite is that it has no tergum, its feet have no pectinate inferior tarsus scales or claw, the feetⅠgenu has only one solenidia, and feet Ⅲ and Ⅳ have no solenidias.

  16. Mechanisms accounting for fluoroquinolone resistance in Escherichia coli clinical isolates.

    Science.gov (United States)

    Morgan-Linnell, Sonia K; Becnel Boyd, Lauren; Steffen, David; Zechiedrich, Lynn

    2009-01-01

    Fluoroquinolone MICs are increased through the acquisition of chromosomal mutations in the genes encoding gyrase (gyrA and gyrB) and topoisomerase IV (parC and parE), increased levels of the multidrug efflux pump AcrAB, and the plasmid-borne genes aac(6')-Ib-cr and the qnr variants in Escherichia coli. In the accompanying report, we found that ciprofloxacin, gatifloxacin, levofloxacin, and norfloxacin MICs for fluoroquinolone-resistant E. coli clinical isolates were very high and widely varied (L. Becnel Boyd, M. J. Maynard, S. K. Morgan-Linnell, L. B. Horton, R. Sucgang, R. J. Hamill, J. Rojo Jimenez, J. Versalovic, D. Steffen, and L. Zechiedrich, Antimicrob. Agents Chemother. 53:229-234, 2009). Here, we sequenced gyrA, gyrB, parC, and parE; screened for aac(6')-Ib-cr and qnrA; and quantified AcrA levels in E. coli isolates for which patient sex, age, location, and site of infection were known. We found that (i) all fluoroquinolone-resistant isolates had gyrA mutations; (ii) approximately 85% of gyrA mutants also had parC mutations; (iii) the ciprofloxacin and norfloxacin MICs for isolates harboring aac(6')-Ib-cr ( approximately 23%) were significantly higher, but the gatifloxacin and levofloxacin MICs were not; (iv) no isolate had qnrA; and (v) approximately 33% of the fluoroquinolone-resistant isolates had increased AcrA levels. Increased AcrA correlated with nonsusceptibility to the fluoroquinolones but did not correlate with nonsusceptibility to any other antimicrobial agents reported from hospital antibiograms. Known mechanisms accounted for the fluoroquinolone MICs of 50 to 70% of the isolates; the remaining included isolates for which the MICs were up to 1,500-fold higher than expected. Thus, additional, unknown fluoroquinolone resistance mechanisms must be present in some clinical isolates.

  17. Conversion from clinically isolated syndrome to multiple sclerosis

    DEFF Research Database (Denmark)

    Kuhle, J; Disanto, G; Dobson, R

    2015-01-01

    BACKGROUND AND OBJECTIVE: We explored which clinical and biochemical variables predict conversion from clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (CDMS) in a large international cohort. METHODS: Thirty-three centres provided serum samples from 1047 CIS cases...... with at least two years' follow-up. Age, sex, clinical presentation, T2-hyperintense lesions, cerebrospinal fluid (CSF) oligoclonal bands (OCBs), CSF IgG index, CSF cell count, serum 25-hydroxyvitamin D3 (25-OH-D), cotinine and IgG titres against Epstein-Barr nuclear antigen 1 (EBNA-1) and cytomegalovirus were...

  18. Antibiotic Susceptibilities and Serotyping of Clinical Streptococcus Agalactiae Isolates

    Directory of Open Access Journals (Sweden)

    Altay Atalay

    2011-11-01

    Full Text Available Objective: Streptococcus agalactiae (Group B streptococci, GBS are frequently responsible for sepsis and meningitis seen in the early weeks of life. GBS may cause perinatal infection and premature birth in pregnant women. The aim of this study was to serotype GBS strains isolated from clinical samples and evaluate their serotype distribution according to their susceptibilities to antibiotics and isolation sites. Material and Methods: One hundred thirty one S. agalactiae strains isolated from the clinical samples were included in the study. Of the strains, 99 were isolated from urine, 20 from soft tissue, 10 from blood and 2 from vaginal swab. Penicillin G and ceftriaxone susceptibilities of GBS were determined by the agar dilution method. Susceptibilities to erythromycin, clindamycin, vancomycin and tetracycline were determined by the Kirby-Bauer method according to CLSI criteria. Serotyping was performed using the latex aglutination method using specific antisera (Ia, Ib, II-VIII. Results: While in 131 GBS strains, serotypes VII and VIII were not detected, the most frequently isolated serotypes were types Ia (36%, III (30.5% and II (13% respectively. Serotype Ia was the most frequently seen serotype in all samples. All GBS isolates were susceptible to penicilin G, ceftriaxone and vancomycin. Among the strains, tetracycline, erythromycin and clindamycin resistance rates were determined as 90%, 14.5%, and 13% respectively. Conclusion: Penicillin is still the first choice of treatment for the infections with all serotypes of S. agalactiae in Turkey.

  19. Detection of -Lactamases in nosocomial gram negative clinical isolates

    Directory of Open Access Journals (Sweden)

    Rodrigues C

    2004-01-01

    Full Text Available -lactamases represent the most common mechanism of -lactam resistance. Extended spectrum -lactamases (ESBLs represent a major group of -lactamses currently being identified worldwide in large numbers along with inducible AmpC -lactamases and derepressed mutants. The present study was done to detect -lactamase production in clinical isolates by rearranging routine discs used in reporting susceptibility to specifically assess ESBLs, AmpC -lactamases (both inducible and hyperproducers i.e., derepressed mutants. A total of 286 clinical isolates were studied using a novel predictor disc approximation method to detect the above mechanisms of resistance with careful use and placement of antimicrobial discs. Of the 286 isolates, 151(53% were ESBL producers of which 131(46% were also derepressed mutants while remaining 20(7% were plain ESBL producers. Forty (14% were plain derepressed mutants. Inducible AmpC -lactamase production was detected in 19(7% of the isolates. The commonest ESBL producers were E.coli and K. pneumoniae. The high incidence of -lactamase production due to multiple mechanisms in clinical isolates is alarming and urgent action needs to be taken from both a therapeutic and infection control perspective.

  20. RESPONSES OF OYSTER (CRASSOSTREA VIRGINICA) HEMOCYTES TO NONPATHOGENIC AND CLINICAL ISOLATES OF VIBRIO PARAHAEMOLYTICUS

    Science.gov (United States)

    Bacterial uptake by oysters (Crassostrea virginica) and bactericidal activity of oyster hemocytes were studied using four environmental isolates and three clinical isolates of Vibrio parahaemolyticus. Clinical isolates (2030, 2062, 2107) were obtained from gastroenteritis patien...

  1. The Genome of the Western Clawed Frog Xenopus tropicalis

    Energy Technology Data Exchange (ETDEWEB)

    Hellsten, Uffe; Harland, Richard M.; Gilchrist, Michael J.; Hendrix, David; Jurka, Jerzy; Kapitonov, Vladimir; Ovcharenko, Ivan; Putnam, Nicholas H.; Shu, Shengqiang; Taher, Leila; Blitz, Ira L.; Blumberg, Bruce; Dichmann, Darwin S.; Dubchak, Inna; Amaya, Enrique; Detter, John C.; Fletcher, Russell; Gerhard, Daniela S.; Goodstein, David; Graves, Tina; Grigoriev, Igor V.; Grimwood, Jane; Kawashima, Takeshi; Lindquist, Erika; Lucas, Susan M.; Mead, Paul E.; Mitros, Therese; Ogino, Hajime; Ohta, Yuko; Poliakov, Alexander V.; Pollet, Nicolas; Robert, Jacques; Salamov, Asaf; Sater, Amy K.; Schmutz, Jeremy; Terry, Astrid; Vize, Peter D.; Warren, Wesley C.; Wells, Dan; Wills, Andrea; Wilson, Richard K.; Zimmerman, Lyle B.; Zorn, Aaron M.; Grainger, Robert; Grammer, Timothy; Khokha, Mustafa K.; Richardson, Paul M.; Rokhsar, Daniel S.

    2009-10-01

    The western clawed frog Xenopus tropicalis is an important model for vertebrate development that combines experimental advantages of the African clawed frog Xenopus laevis with more tractable genetics. Here we present a draft genome sequence assembly of X. tropicalis. This genome encodes over 20,000 protein-coding genes, including orthologs of at least 1,700 human disease genes. Over a million expressed sequence tags validated the annotation. More than one-third of the genome consists of transposable elements, with unusually prevalent DNA transposons. Like other tetrapods, the genome contains gene deserts enriched for conserved non-coding elements. The genome exhibits remarkable shared synteny with human and chicken over major parts of large chromosomes, broken by lineage-specific chromosome fusions and fissions, mainly in the mammalian lineage.

  2. Susceptibility of clinical isolates of uropathogenic bacteria from ...

    African Journals Online (AJOL)

    Resistance of uropathogens to antibiotics has been on increase and responsible for increased mortality and morbidity among patients. Clinical isolates (22) of uropathogenic bacteria comprising Escherichia coli, Klebsiella Pneumoniae, Proteus mirabilis and Staphylococcus aureus were tested for susceptibility to standard ...

  3. Multidrug and vancomycin resistance among clinical isolates of ...

    African Journals Online (AJOL)

    The prevalence of multi-drug and vancomycin resistance strains of S. aureus from clinical samples was determined using disk diffusion and agar dilution methods respectively. Results: The result showed (165)82.5% of the isolates were resistant to ≥3 antibiotics tested. They were highly resistant to ceftazidime 180(90%), ...

  4. Epidemiology of Clinical Isolates of Mycobacterium tuberculosis at ...

    African Journals Online (AJOL)

    Despite the huge burden of tuberculosis (TB) in Nigeria, case detection rate of infectious cases still remain low, thus constituting obstacle to eradication of the disease in the community. We carried out a 15 month (1st January 2008 to 30th March 2009) retrospective review of epidemiology of clinical isolates of M.

  5. EFFECT OT KUNNU-ZAKI ON CLINICAL BACTERIAL ISOLATES

    African Journals Online (AJOL)

    omidiji

    2012-03-08

    Mar 8, 2012 ... antimicrobial effect represents another property for Kunun-zaki and obviates the possibility of public health risk in its consumption. Key words: Kunnu-zaki, clinical isolates, antibiotic sensitivity. INTRODUCTION. Kunnu-zaki is a cereal food drink that has become a popular refreshing non-alcoholic beverage ...

  6. Multiple antimicrobial resistance in bacterial isolates from clinical ...

    African Journals Online (AJOL)

    A total of 545 clinical specimens (pus, blood, urine, and stool) and environmental specimens (air sample, saline solution, nasal swabs etc) were cultured for isolation and identification of aerobic bacteria and antimicrobial susceptibility testing. Out of these, 356(65%) specimens yielded one or more bacterial strains. Frequent ...

  7. Antimicrobial Resistance Trend of Bacteria from Clinical Isolates: An ...

    African Journals Online (AJOL)

    For decades, antimicrobials have proven useful for the treatment of bacterial infections. However, the immergence of antimicrobial resistance has become a major challenge to public health in many countries. The aim of this study was to investigate the antimicrobial susceptibility of bacterial isolates from clinical sources.

  8. Molecular epidemiology of clinical isolates of Pseudomonas aeruginosa isolated from horses in Ireland

    Directory of Open Access Journals (Sweden)

    Tazumi A

    2009-07-01

    Full Text Available Abstract Clinical isolates (n = 63 of Pseudomonas aeruginosa obtained from various sites in 63 horses were compared using ERIC2 RAPD PCR to determine their genetic relatedness. Resulting banding patterns (n = 24 genotypes showed a high degree of genetic heterogeneity amongst all isolates examined, indicating a relative non-clonal relationship between isolates from these patients, employing this genotyping technique. This study characterised 63 clinical isolates into 24 distinct genotypes, with the largest cluster (genotype E accounting for 10/63 (15.9% of the isolates. ERIC2 RAPD PCR proved to be a highly discriminatory molecular typing tool of P. aeruginosa in isolates recovered from horses. With the adoption of several controls to aid reproducibility, this technique may be useful as an alternative to PFGE, particularly in epidemiological investigations of outbreaks where speed may be a significant parameter. This is the first report of clonal heterogeneity amongst P. aeruginosa from horses and demonstrated that ERIC RAPD PCR is a rapid method for the examination of this species in horses, which may be useful in outbreak analysis.

  9. Reclassification of Candida guilliermondii FTI 20037 as Candida tropicalis based on molecular phylogenetic analysis Reclassificação de Candida guilliermondii FTI 20037 como Candida tropicalis baseada na análise filogenética molecular

    Directory of Open Access Journals (Sweden)

    Luanne Helena Augusto Lima

    2003-11-01

    Full Text Available Yeasts of the genus Candida are of clinical importance and also have many industrial applications, mainly in the food industry. The yeast Candida guilliermondii FTI 20037 has been extensively studied in order to establish a biotechnological process for the production of xylitol. The goal of this study was to verify the taxonomic classification of this strain based on the analysis of rDNA sequences and the xyl1 gene. DNA fragments from these sequences were amplified by PCR and BLAST analysis revealed strong identity with the corresponding sequences from Candida tropicalis. Based on these results, we propose that C. guilliermondii FTI 20037 must be reclassified as C. tropicalis.As leveduras do gênero Candida possuem tanto importância clínica como diversas aplicações industriais, principalmente na indústria de alimentos. A levedura Candida guilliermondii FTI 20037 tem sido exaustivamente estudada pois pretende-se utilizá-la no estabelecimento de um processo biotecnológico para a produção de xilitol. O objetivo deste trabalho foi verificar a classificação taxonômica desta levedura por análise de sequências do rDNA e do gene xyl1. Fragmentos correspondentes a estas regiões foram amplificados por PCR e a análise destas sequências por BLAST revelou alta identidade com sequências correspondentes de Candida tropicalis. Estes resultados nos levam a propor que C. guilliermondii FTI 20037 deva ser reclassificada como C. tropicalis.

  10. Molecular identification of clinical Nocardia isolates from India.

    Science.gov (United States)

    Rudramurthy, Shivaprakash M; Honnavar, Prasanna; Kaur, Harsimran; Samanta, Palash; Ray, Pallab; Ghosh, Anup; Chakrabarti, Arunaloke

    2015-10-01

    The epidemiology of nocardiosis is evolving with increasing number of Nocardia spp. causing human infection. In recent years, molecular techniques have been used to identify Nocardia spp. There are limited data available on the spectrum of Nocardia spp. isolated from clinical samples in India. Here, a molecular study was carried on 30 clinical isolates maintained in our National Culture Collection to evaluate the techniques used for identifying the agents. The isolates were identified by sequencing two promising genes: the 16S rRNA gene and hsp65. Both hsp65 and the 16S rRNA gene could reliably identify 90 % of Nocardia isolates, i.e. N. farcinica, N. cyriacigeorgica, N. brasiliensis, N. otitidiscaviarum, N. amamiensis and N. pneumoniae. The mean percentage dissimilarity of sequence identification was higher using the hsp65 gene (4 %, range 0-7.9 %) compared with the 16S rRNA gene (2.3 %, range 0-8.9 %). Two isolates that showed ambiguous results in both the short segment of the 16S rRNA gene and hsp65 sequences could be resolved by sequencing a larger fragment (∼1000 bp) of the 16S rRNA gene. Both of these isolates were identified as N. beijingensis with similarities of 99.8 and 100 % compared with the standard strain. Genotyping of N. cyriacigeorgica strains was performed using hsp65 gene sequences and compared with previously described genotypes. Our N. cyriacigeorgica isolates belonged to genotype 1 (n = 4) and genotype 2 (n = 2). The present study highlights a wide spectrum of Nocardia spp. in India and emphasizes the need for molecular techniques for identification to the species level.

  11. Epidemiology and antifungal susceptibility of candidemia isolates of non-albicans Candida species from cancer patients

    Science.gov (United States)

    Wu, Ping-Feng; Liu, Wei-Lun; Hsieh, Min-Han; Hii, Ing-Moi; Lee, Yu-Lin; Lin, Yi-Tsung; Ho, Mao-Wang; Liu, Chun-Eng; Chen, Yen-Hsu; Wang, Fu-Der

    2017-01-01

    Candidemia is a growing concern worldwide, and its species distribution has shifted toward non-albicans Candida in recent decades, especially in patients with malignancy. This study aimed to update the epidemiology and antifungal susceptibility of non-albicans candidemia isolates from the cancer patients. Adult cancer patients with non-albicans candidemia were recruited, and clinical data were retrospectively collected from five medical centers in Taiwan from 1 July 2011 to 30 June 2014. In vitro susceptibility was determined by the broth dilution method using a Sensititre YeastOne system and interpreted according to the guidelines of the Clinical and Laboratory Standards Institute. A total of 346 episodes of non-albicans candidemia were identified in cancer patients. Candida tropicalis was the most common species (n=145, 41.9%) and had the highest resistance rate to fluconazole (n=17, 13.9%) among all the preserved isolates, including C. tropicalis, Candida glabrata and Candida parapsilosis. A higher Charlson comorbidity index, non-albicans candidemia due to C. tropicalis, neutropenia and septic shock were independent predictors of 28-day mortality. In conclusion, the species distribution and antifungal susceptibility of non-albicans candidemia isolates in our study differed from those in Western countries, providing useful information about local epidemiology for the selection of empirical antifungal agents for cancer patients. PMID:29018251

  12. Homogeneity of Danish environmental and clinical isolates of Shewanella algae

    DEFF Research Database (Denmark)

    Vogel, Birte Fonnesbech; Holt, H.M.; Gerner-Smidt, P.

    2000-01-01

    Danish isolates of Shewanella algae constituted by whole-cell protein profiling a very homogeneous group, and no clear distinction was seen between strains from the marine environment and strains of clinical origin. Although variation between all strains was observed by ribotyping and random...... amplified polymorphic DNA analysis, no clonal relationship between infective strains was found. From several patients, clonally identical strains of S. algae were reisolated up to 8 months after the primary isolation, indicating that the same strain may be able to maintain the infection....

  13. Identification of Candida species isolated from vulvovaginitis in Mashhad, Iran by Use of MALDI-TOF MS

    Directory of Open Access Journals (Sweden)

    Majid Alizadeh

    2017-12-01

     Of the 65 isolates analyzed, 61 (93.8% were recognised by MALDI-TOF mass spectrometry and for four isolates (6.1% only not relabile identifications were achieved. In this study, the most frequently isolated species were Candida albicans (58.5%, followed by Candida tropicalis (16.9%, Candida glabrata (7.7%, Candida parapsilosis (7.7% and Candida guillermondii (3.1%.  Conclusion presented results demonstrate that the MALDI TOF mass spectrometry is a fast and reliable technique, and has the potential to replace conventional phenotypic identification of Candida species and other yeast strains routinely isolated in clinical microbiology laboratories.

  14. Molecular identification of Sporothrix clinical isolates in China*

    Science.gov (United States)

    Liu, Ting-ting; Zhang, Ke; Zhou, Xun

    2014-01-01

    In this study, we investigated the molecular phylogeny of 64 clinical isolates which were identified as Sporothrix schenckii sensu lato by morphological identification. All of the strains were isolates from patients from several provinces in China. The phylogeny was inferred by DNA sequence analyses based on datasets of the ribosomal internal transcribed spacer (ITS) and a combined ITS and partial β-tubulin region. Reference sequences were retrieved from GenBank. Results showed that all of the isolates were clustered in a distinct clade with a type of Sporothrix globosa. Our analysis showed that S. globosa is the causal agent of the tested sporotrichosis in China, rather than S. schenckii that was generally believed to be the case. The existence of S. schenckii in China remains to be confirmed. This study improved our understanding of the distribution of the species in S. schenckii complex. PMID:24390750

  15. Molecular identification of Sporothrix clinical isolates in China.

    Science.gov (United States)

    Liu, Ting-ting; Zhang, Ke; Zhou, Xun

    2014-01-01

    In this study, we investigated the molecular phylogeny of 64 clinical isolates which were identified as Sporothrix schenckii sensu lato by morphological identification. All of the strains were isolates from patients from several provinces in China. The phylogeny was inferred by DNA sequence analyses based on datasets of the ribosomal internal transcribed spacer (ITS) and a combined ITS and partial β-tubulin region. Reference sequences were retrieved from GenBank. Results showed that all of the isolates were clustered in a distinct clade with a type of Sporothrix globosa. Our analysis showed that S. globosa is the causal agent of the tested sporotrichosis in China, rather than S. schenckii that was generally believed to be the case. The existence of S. schenckii in China remains to be confirmed. This study improved our understanding of the distribution of the species in S. schenckii complex.

  16. A Xenopus tropicalis oligonucleotide microarray works across species using RNA from Xenopus laevis.

    Science.gov (United States)

    Chalmers, Andrew D; Goldstone, Kim; Smith, James C; Gilchrist, Mike; Amaya, Enrique; Papalopulu, Nancy

    2005-03-01

    Microarrays have great potential for the study of developmental biology. As a model system Xenopus is well suited for making the most of this potential. However, Xenopus laevis has undergone a genome wide duplication meaning that most genes are represented by two paralogues. This causes a number of problems. Most importantly the presence of duplicated genes mean that a X. laevis microarray will have less or even half the coverage of a similar sized microarray from the closely related but diploid frog Xenopus tropicalis. However, to date, X. laevis is the most commonly used amphibian system for experimental embryology. Therefore, we have tested if a microarray based on sequences from X. tropicalis will work across species using RNA from X. laevis. We produced a pilot oligonucleotide microarray based on sequences from X. tropicalis. The microarray was used to identify genes whose expression levels changed during early X. tropicalis development. The same assay was then carried out using RNA from X. laevis. The cross species experiments gave similar results to those using X. tropicalis RNA. This was true at the whole microarray level and for individual genes, with most genes giving similar results using RNA from X. laevis and X. tropicalis. Furthermore, the overlap in genes identified between a X. laevis and a X. tropicalis set of experiments was only 12% less than the overlap between two sets of X. tropicalis experiments. Therefore researchers can work with X. laevis and still make use of the advantages offered by X. tropicalis microarrays.

  17. Clinical evaluation of isolated abutment teeth in removable partial dentures

    Directory of Open Access Journals (Sweden)

    Zarrati S

    2011-02-01

    Full Text Available "nBackground and Aims: Nowadays, removable partial dentures are applied to patients who are not able to use dental implants or fixed prosthesis. Although based on the studies the users of removable partial dentures are in the risk of plaque accumulation and unacceptable changes such as gingivitis, periodontitis and mobility in abutment tooth. It is not clear whether the negative effects of removable partial dentures are more on the isolated teeth which are a kind of abutment adjacent to endentulous area in both sides. The purpose of this study was to investigate the clinical condition of isolated abutment teeth without splinting in comparison to control abutment from the aspects of B.O.P (bleeding on probing, mobility, pocket depth and gingivitis."nMaterials and Methods: In this cross-sectional study, the prepared questionnaires were filled out by 50 patients who received removable partial dentures in department of removable prosthodontics of dental school of Tehran University of Medical Sciences. The patients had isolated abutment tooth and did not have any systemic disease. The obtained data were analyzed. Using Wilcoxon, exact Fisher and Kruskal-Wallis test."nResults: B.O.P (P=0.004, pocket depth (P=0.035, and mobility (P<0.001 in isolated abutments were more than those in control abutments, but there were not significant differences in the degree of caries (P=0.083 and gingivitis (P=0.07."nConclusion: This study showed that clinical condition of isolated abutments is worse than that of control abutments. More attention should be paid to healthiness of isolated teeth without splinting and periodic follow ups should be done in these cases.

  18. In vitro antimicrobial susceptibility in clinical isolates of Enterococcus species

    OpenAIRE

    Calderón-Jaimes Ernesto; Arredondo-García José Luis; Aguilar-Ituarte Felipe; García-Roca Pilar

    2003-01-01

    OBJECTIVE: To describe the antimicrobial activity of several antimicrobial agents against 97 clinical significant isolates of Enterococcus spp. MATHERIAL AND METHODS: During a 2-year prospective study at Instituto Nacional de Pediatria (National Institute of Pediatrics) in Mexico City. Ninety seven strains of Enterococcus spp. (60 E. faecalis and 37 E. faecium) were tested against 11 antibiotics. Susceptibility tests were performed with agar, according to the standards of the sNational Commit...

  19. Identification and Pathogenic Potential of Clinical Bacillus and Paenibacillus Isolates.

    Directory of Open Access Journals (Sweden)

    Francesco Celandroni

    Full Text Available The soil-related Bacillus and Paenibacillus species have increasingly been implicated in various human diseases. Nevertheless, their identification still poses problems in the clinical microbiology laboratory and, with the exception of Bacillus anthracis and Bacillus cereus, little is known on their pathogenicity for humans. In this study, we evaluated the use of matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS in the identification of clinical isolates of these genera and conducted genotypic and phenotypic analyses to highlight specific virulence properties. Seventy-five clinical isolates were subjected to biochemical and MALDI-TOF MS identification. 16S rDNA sequencing and supplemental tests were used to solve any discrepancies or failures in the identification results. MALDI-TOF MS significantly outperformed classical biochemical testing for correct species identification and no misidentification was obtained. One third of the collected strains belonged to the B. cereus species, but also Bacillus pumilus and Bacillus subtilis were isolated at high rate. Antimicrobial susceptibility testing showed that all the B. cereus, B. licheniformis, B. simplex, B. mycoides, Paenibacillus glucanolyticus and Paenibacillus lautus isolates are resistant to penicillin. The evaluation of toxin/enzyme secretion, toxin-encoding genes, motility, and biofilm formation revealed that B. cereus displays the highest virulence potential. However, although generally considered nonpathogenic, most of the other species were shown to swim, swarm, produce biofilms, and secrete proteases that can have a role in bacterial virulence. In conclusion, MALDI-TOF MS appears useful for fast and accurate identification of Bacillus and Paenibacillus strains whose virulence properties make them of increasing clinical relevance.

  20. Identification and Pathogenic Potential of Clinical Bacillus and Paenibacillus Isolates.

    Science.gov (United States)

    Celandroni, Francesco; Salvetti, Sara; Gueye, Sokhna Aissatou; Mazzantini, Diletta; Lupetti, Antonella; Senesi, Sonia; Ghelardi, Emilia

    2016-01-01

    The soil-related Bacillus and Paenibacillus species have increasingly been implicated in various human diseases. Nevertheless, their identification still poses problems in the clinical microbiology laboratory and, with the exception of Bacillus anthracis and Bacillus cereus, little is known on their pathogenicity for humans. In this study, we evaluated the use of matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS) in the identification of clinical isolates of these genera and conducted genotypic and phenotypic analyses to highlight specific virulence properties. Seventy-five clinical isolates were subjected to biochemical and MALDI-TOF MS identification. 16S rDNA sequencing and supplemental tests were used to solve any discrepancies or failures in the identification results. MALDI-TOF MS significantly outperformed classical biochemical testing for correct species identification and no misidentification was obtained. One third of the collected strains belonged to the B. cereus species, but also Bacillus pumilus and Bacillus subtilis were isolated at high rate. Antimicrobial susceptibility testing showed that all the B. cereus, B. licheniformis, B. simplex, B. mycoides, Paenibacillus glucanolyticus and Paenibacillus lautus isolates are resistant to penicillin. The evaluation of toxin/enzyme secretion, toxin-encoding genes, motility, and biofilm formation revealed that B. cereus displays the highest virulence potential. However, although generally considered nonpathogenic, most of the other species were shown to swim, swarm, produce biofilms, and secrete proteases that can have a role in bacterial virulence. In conclusion, MALDI-TOF MS appears useful for fast and accurate identification of Bacillus and Paenibacillus strains whose virulence properties make them of increasing clinical relevance.

  1. Investigation of biofilm formation in clinical isolates of Staphylococcus aureus.

    Science.gov (United States)

    Cassat, James E; Lee, Chia Y; Smeltzer, Mark S

    2007-01-01

    As with many other bacterial species, the most commonly used method to assess staphylococcal biofilm formation in vitro is the microtiter plate assay. This assay is particularly useful for comparison of multiple strains including large-scale screens of mutant libraries. When such screens are applied to the coagulase-negative staphylococci in general, and Staphylococcus epidermidis in particular, they are relatively straightforward by comparison with microtiter plate assays used to assess biofilm formation in other bacterial species. However, in the case of clinical isolates of Staphylococcus aureus, including methicillin-resistant S. aureus, we have found it necessary to employ specific modifications including precoating of the wells of the microtiter plate with plasma proteins and supplementation of the medium with both salt and glucose. In this chapter, we describe the microtiter plate assay in the specific context of clinical isolates of S. aureus and the use of these modifications. A second in vitro method, which also is generally dependent on coating with plasma proteins and supplementation of the growth medium, is the use of flow cells. In this method, bacteria are allowed to attach to a surface and then monitored with respect to their ability to remain attached to the substrate and differentiate into mature biofilms under the constant pressure of fluid shear force. Although flow cells are not applicable to large-scale screens, we have found that they provide a more reproducible and accurate assessment of the capacity of S. aureus clinical isolates to form a biofilm. They also provide a means of analyzing structural differences in biofilm architecture and isolating bacteria and/or spent media for analysis of physiological and metabolic changes associated with the adaptive response to growth in a biofilm. While a primary focus of this chapter is on the use of in vitro assays to assess biofilm formation in clinical isolates of S. aureus, it is important to

  2. Predicting outcome in clinically isolated syndrome using machine learning

    Science.gov (United States)

    Wottschel, V.; Alexander, D.C.; Kwok, P.P.; Chard, D.T.; Stromillo, M.L.; De Stefano, N.; Thompson, A.J.; Miller, D.H.; Ciccarelli, O.

    2014-01-01

    We aim to determine if machine learning techniques, such as support vector machines (SVMs), can predict the occurrence of a second clinical attack, which leads to the diagnosis of clinically-definite Multiple Sclerosis (CDMS) in patients with a clinically isolated syndrome (CIS), on the basis of single patient's lesion features and clinical/demographic characteristics. Seventy-four patients at onset of CIS were scanned and clinically reviewed after one and three years. CDMS was used as the gold standard against which SVM classification accuracy was tested. Radiological features related to lesional characteristics on conventional MRI were defined a priori and used in combination with clinical/demographic features in an SVM. Forward recursive feature elimination with 100 bootstraps and a leave-one-out cross-validation was used to find the most predictive feature combinations. 30 % and 44 % of patients developed CDMS within one and three years, respectively. The SVMs correctly predicted the presence (or the absence) of CDMS in 71.4 % of patients (sensitivity/specificity: 77 %/66 %) at 1 year, and in 68 % (60 %/76 %) at 3 years on average over all bootstraps. Combinations of features consistently gave a higher accuracy in predicting outcome than any single feature. Machine-learning-based classifications can be used to provide an “individualised” prediction of conversion to MS from subjects' baseline scans and clinical characteristics, with potential to be incorporated into routine clinical practice. PMID:25610791

  3. [Comparison of Phoenix™ Yeast ID Panel and API® ID 32C commercial systems for the identification of Candida species isolated from clinical samples].

    Science.gov (United States)

    Gayibova, Ülkü; Dalyan Cılo, Burcu; Ağca, Harun; Ener, Beyza

    2014-07-01

    Opportunistic fungal pathogens are one of the important causes of nosocomial infections, and several different types of yeasts, especially Candida species are increasingly recovered from immunocompromised patients. Since many of the yeasts are resistant to the commonly used antifungal agents, the introduction of appropriate therapy depends on rapid and accurate identification. The aims of this study were to compare the commercial identification systems namely API® ID 32C (bioMerieux, France) and Phoenix™ Yeast ID Panel (Becton Dickinson Diagnostics, USA) for the identification of Candida species and to evaluate the effect of morphological findings in the identification process. A total of 211 yeast strains isolated from different clinical samples (111 urine, 34 blood/vascular catheter, 27 upper/lower respiratory tract, 16 abscess/pus, 13 throat/vagina swabs and 10 sterile body fluids) of 137 patients hospitalized in Uludag University Health and Research Center between October 2013 to January 2014, were included in the study. Samples were cultured on blood agar, chromogenic agar (CHROMagar Candida, BD, USA) and Saboraud's dextrose agar (SDA), and isolated yeast colonies were evaluated with germ tube test and morphological examination by microscopy on cornmeal/Tween-80 agar. The isolates were identified as well by two commercial systems according to the manufacturers' recommendations. Discrepant results between the systems were tried to be resolved by using morphological characteristics of the yeasts. Of the isolates 159 were identified identical by both of the systems, and the concordance between those systems were estimated as 75.4%. According to the concordant identification, the most frequently isolated species was C.albicans (44.1%) followed by C.tropicalis (9.9%), C.glabrata (9.5%), C.parapsilosis (8.5%) and C.kefyr (8.1%). The concordance rate was 81.7% in identification of frequently isolated species (C.albicans, C.tropicalis, C.parapsilosis, C.glabrata, C

  4. Remobilization of Tol2 transposons in Xenopus tropicalis

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    Wells Dan E

    2010-01-01

    Full Text Available Abstract Background The Class II DNA transposons are mobile genetic elements that move DNA sequence from one position in the genome to another. We have previously demonstrated that the naturally occurring Tol2 element from Oryzias latipes efficiently integrates its corresponding non-autonomous transposable element into the genome of the diploid frog, Xenopus tropicalis. Tol2 transposons are stable in the frog genome and are transmitted to the offspring at the expected Mendelian frequency. Results To test whether Tol2 transposons integrated in the Xenopus tropicalis genome are substrates for remobilization, we injected in vitro transcribed Tol2 mRNA into one-cell embryos harbouring a single copy of a Tol2 transposon. Integration site analysis of injected embryos from two founder lines showed at least one somatic remobilization event per embryo. We also demonstrate that the remobilized transposons are transmitted through the germline and re-integration can result in the generation of novel GFP expression patterns in the developing tadpole. Although the parental line contained a single Tol2 transposon, the resulting remobilized tadpoles frequently inherit multiple copies of the transposon. This is likely to be due to the Tol2 transposase acting in discrete blastomeres of the developing injected embryo during the cell cycle after DNA synthesis but prior to mitosis. Conclusions In this study, we demonstrate that single copy Tol2 transposons integrated into the Xenopus tropicalis genome are effective substrates for excision and random re-integration and that the remobilized transposons are transmitted through the germline. This is an important step in the development of 'transposon hopping' strategies for insertional mutagenesis, gene trap and enhancer trap screens in this highly tractable developmental model organism.

  5. Breeding based remobilization of Tol2 transposon in Xenopus tropicalis.

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    Maura A Lane

    Full Text Available Xenopus is a powerful model for studying a diverse array of biological processes. However, despite multiple methods for transgenesis, relatively few transgenic reporter lines are available and commonly used. Previous work has demonstrated that transposon based strategies are effective for generating transgenic lines in both invertebrate and vertebrate systems. Here we show that the Tol2 transposon can be remobilized in the genome of X. tropicalis and passed through the germline via a simple breeding strategy of crossing transposase expressing and transposon lines. This remobilization system provides another tool to exploit transgenesis and opens new opportunities for gene trap and enhancer trap strategies.

  6. Characterization of integrons in Burkholderia cepacia clinical isolates

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    Linda Furlanis

    2010-03-01

    Full Text Available Burkholderia cepacia is an opportunistic pathogen able to colonize the airways of Cystic Fibrosis (CF patients, frequently developing chronic infections. In 20% of cases these infections cause severe and poorly controlled pathological situations because of the intrinsic antibiotic resistance expressed by the microorganism. CF patients are often subjected to antibiotic therapy: this facilitates the acquisition of antibiotic resistance determinants by the infecting bacteria. Integrons are mobile genetic elements that are widespread in bacterial populations and favor the acquisition of gene cassettes coding for these determinants.The presence of class 1 integrons was investigated by PCR with primers specific for the 5’ and 3’ ends in Burkholderia isolates recovered from patients in treatment at the CF center of Friuli Venezia Giulia. The same integron, carrying an uncommon allelic form (Ib of the aacA4 gene in its cassette array and conferring resistance to some aminoglycosides, was found in two independent isolates (different RAPD profiles infecting two different patients. In both isolates the integron was carried by plasmids and was still present 3 and 6 years later the first finding. Despite the exchange of integrons between bacterial pathogens is fully described, these items were not frequently found in Burkholderia isolates. Although the clinical relevance of the integron we identified is low (a single gene cassette encoding a widespread resistance,we feel concerned that these genetic elements begin to circulate in this bacterial species, as this could make more and more troublesome the treatment of infections notoriously difficult to eradicate.

  7. In Vitro Susceptibility Test of Different Clinical Isolates against Ceftriaxone

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    Syed Hakim Masood

    2010-06-01

    Full Text Available Objectives: Because of the prevailing penicillin resistance in microorganisms, broad spectrum cephalosporins are used empirically specially in developing countries. The aim of this study is to determine the susceptibility pattern of different gram positive and gram negative pathogens against third generation cephalosporin-ceftriaxone to explore the existing effectiveness of this antibiotic.Methods: 180 clinical isolates of different gram positive and gram negative pathogens including P.mirabilis, S. typhi P.aeruginosa, E. coli, S. aureus and Klebsiella were collected from blood and urine samples of in-patients. 30 isolates of all species were tested against each of six brands of ceftriaxone using in vitro sensitivity tests by disc diffusion method (NCCLS criteria. The susceptibility limit was ≥21 mm zone of inhibition, while moderately susceptible was considered at 20-14 mm, and those isolates which showed >13 mm or no zone of inhibition were resistant to this antibacterial drug.Results: Ceftriaxone was found most effective against S. aureus. While 96.1% of the isolates showed susceptibility towards ceftriaxone, followed by E. coli (95%, P. aeruginosa (92.7%, K. pneumonia (89.4% and S. typhi (87.2%. P. mirabilis showed lowest susceptibility amongst all the test organisms (83.8%.Conclusion: Ceftriaxone can be used as a drug of choice in infections caused by S. aureus, E. coli, P. aurigenosa, K. pneumonia and S. typhi. However, it should be used with other antimicrobial agents in order to increase its effectiveness against P. mirabilis.

  8. Clinical and genetic aspects of familial isolated pituitary adenomas

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    Vladimir Vasilev

    2012-01-01

    Full Text Available Pituitary adenomas represent a group of functionally diverse neoplasms with relatively high prevalence in the general population. Most occur sporadically, but inherited genetic predisposing factors are increasingly recognized. Familial isolated pituitary adenoma is a recently defined clinical entity, and is characterized by hereditary presentation of pituitary adenomas in the absence of clinical and genetic features of syndromic disease such as multiple endocrine neoplasia type 1 and Carney complex. Familial isolated pituitary adenoma is inherited in an autosomal dominant manner and accounted for approximately 2-3% of pituitary tumors in some series. Germline mutations in the aryl-hydrocarbon interacting protein gene are identified in around 25% of familial isolated pituitary adenoma kindreds. Pituitary adenomas with mutations of the aryl-hydrocarbon interacting protein gene are predominantly somatotropinomas and prolactinomas, but non-functioning adenomas, Cushing disease, and thyrotropinoma may also occur. These tumors may present as macroadenomas in young patients and are often relatively difficult to control. Furthermore, recent evidence indicates that aryl-hydrocarbon interacting protein gene mutations occur in >10% of patients with sporadic macroadenomas that occur before 30 years of age, and in >20% of children with macroadenomas. Genetic screening for aryl-hydrocarbon interacting protein gene mutations is warranted in selected high-risk patients who may benefit from early recognition and follow-up.

  9. Genotyping of clinical isolates of Acanthamoeba genus in Venezuela.

    Science.gov (United States)

    Wagner, Carolina; Reyes-Batlle, María; Ysea, María Alejandra Vethencourt; Pérez, Mónica V Galindo; de Rondón, Carmen Guzmán; Paduani, Anaibeth J Nessi; Pérez, Angelyseb Dorta; López-Arencibia, Atteneri; Sifaoui, Ines; de Galindo, María Virginia Pérez; de Suárez, Eva Pérez; Martínez-Carretero, Enrique; Valladares, Basilio; Piñero, José E; Lorenzo-Morales, Jacob

    2016-12-01

    Free-living amoebae of Acanthamoeba genus are opportunistic pathogens distributed worldwide. Strains included in this genus are causative agents of a fatal encephalitis and a sight-threating keratitis in humans and other animals. In this study, 550 clinical samples which were collected between 1984 and 2014 from different patients with suspected infections due to Acanthamoeba were initially screened for the presence of this amoebic genus at the Laboratorio de Amibiasis-Escuela de Bioanálisis at the Universidad Central de Venezuela. Samples were cultured in 2% Non-Nutrient agar plates seeded with a layer of heat killed Escherichia coli. From the 550 clinical samples included in this study, 18 of them were positive for Acanthamoeba genus after culture identification. Moreover, positive samples were confirmed after amplification of the Diagnostic Fragment 3 (DF3) of the Acanthamoeba18S rDNA genus and sequencing was carried out in order to genotype the isolated strains of Acanthamoeba. Furthermore, the pathogenic potential of the strains was checked by performing thermotolerance and osmotolerance assays. Sequencing of the DF3 region resulted in the identification of genotype T4 in all the isolated strains. Moreover, most isolates were thermotolerant or both thermotolerant and osmotolerant and thus were classified as potentially pathogenic strains. To the best of our knowledge, this is the first report on the molecular characterization at the genotype level of Acanthamoeba strains in Venezuela.

  10. Analysis of intracellular expressed proteins of Mycobacterium tuberculosis clinical isolates

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    Singhal Neelja

    2012-03-01

    Full Text Available Abstract Background Tuberculosis (TB is the most threatening infectious disease globally. Although progress has been made to reduce global incidence of TB, emergence of multidrug resistant (MDR TB threatens to undermine these advances. To combat the disease, novel intervention strategies effective against drug resistant and sensitive subpopulations of M. tuberculosis are urgently required as adducts in the present treatment regimen. Using THP-1 cells we have analyzed and compared the global protein expression profile of broth-cultured and intraphagosomally grown drug resistant and sensitive M.tuberculosis clinical isolates. Results On comparing the two dimensional (2-DE gels, many proteins were found to be upregulated/expressed during intracellular state which were identified by matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS. Four proteins (adenosylhomocysteinase, aspartate carbomyltransferase, putatitive thiosulfate sulfurtransferase and universal stress protein were present in both intracellular MDR and sensitive isolates and three of these belonged to intermediary metabolism and respiration category. Two proteins (alanine dehydrogenase and adenosine kinase of intracellular MDR isolate and two (glucose-6-phosphate isomerase and ATP synthase epsilon chain of intracellular sensitive isolate belonged to intermediary metabolism and respiration category. One protein (Peroxidase/Catalase of intracellular MDR and three (HSPX, 14 kDa antigen and 10 kDa chaperonin of sensitive isolate belonged to virulence, detoxification and adaptation category. ESAT-6 of intracellular MDR belonged to cell wall and cell processes category. Two proteins (Antigen 85-C and Antigen 85-A of intracellular sensitive isolate were involved in lipid metabolism while probable peptidyl-prolyl cis-trans isomerase A was involved in information pathways. Four (Rv0635, Rv1827, Rv0036c and Rv2032 of intracellular MDR and two proteins (Rv2896c and Rv2558c of

  11. In vitro activity of ivermectin against Staphylococcus aureus clinical isolates

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    Shoaib Ashraf

    2018-02-01

    Full Text Available Abstract Background Ivermectin is an endectocide against many parasites. Though being a macrocyclic lactone, its activity against bacteria has been less known, possibly due to the fact that micromolar concentrations at tissue levels are required to achieve a therapeutic effect. Among pathogenic bacteria of major medical significance, Staphylococcus aureus cause a number of diseases in a wide variety of hosts including humans and animals. It has been attributed as one of the most pathogenic organisms. The emergence of methicillin resistance has made the treatment of S. aureus even more difficult as it is now resistant to most of the available antibiotics. Thus, search for alternate anti-staphylococcal agents requires immediate attention. Methods Twenty-one clinical isolates of S. aureus were isolated from bovine milk collected from Lahore and Faisalabad Pakistan. Different anthelmintics including levamisole, albendazole and ivermectin were tested against S. aureus to determine their minimum inhibitory concentrations. This was followed-up by growth curve analysis, spot assay and time-kill kinetics. Results The results showed that ivermectin but not levamisole or albendazole exhibited a potent anti-staphylococcal activity at the concentrations of 6.25 and 12.5 μg/ml against two isolates. Interestingly, one of the isolate was sensitive while the other was resistant to methicillin/cefoxitin. Conclusions Our novel findings indicate that ivermectin has an anti-bacterial effect against certain S. aureus isolates. However, to comprehend why ivermectin did not inhibit the growth of all Staphylococci needs further investigation. Nevertheless, we have extended the broad range of known pharmacological effects of ivermectin. As pharmacology and toxicology of ivermectin are well known, its further development as an anti-staphylococcal agent is potentially appealing.

  12. Isolation and antibiogram of Staphylococcus, Streptococcus and Escherichia coli isolates from clinical and subclinical cases of bovine mastitis

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    Nihar Nalini Mohanty,

    2013-08-01

    Full Text Available Aim: The present study was aimed to isolate and evaluate the continuous change in the pattern of drug resistance showed by different mastitogenic organisms, isolated from clinical and subclinical cases of mastitis.Materials and Methods: The study was carried out using 150 milk samples received from various clinical and subclinical cases, from which the causative organisms were isolated and subjected to in vitro antibiotic sensitivity test.Results: The bacteriological analysis of the samples indicated the presence of both Gram positive and Gram negative organisms followed by isolation of isolates like Staphylococcus, E. coli, Streptococcus, Bacillus, Corynebacterium, Listeria, Klebsiella. The in vitro sensitivity of Staphylococcus, E. coli and Streptococcus isolates revealed that they were more sensitive towards newer antimicrobials like Levofloxacin and Enrofloxacin.Conclusion: The prevalence of Staphylococcus was found to be maximum followed by Streptococcus and E. coli among the isolated organisms. Levofloxacin and Enrofloxacin were found to be most effective against the targeted isolates.

  13. Antimicrobial sensitivity profile of Staphylococcus spp. Isolated from clinical mastitis

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    Thamires Martins

    2012-12-01

    Full Text Available Inflammation of the mammary gland, which is also known as mastitis, occupies a prominent place among the diseases that affect dairy cattle, having a great economic importance in the dairy sector. Mastitis may have different origins, however, infectious mastitis is the most frequent and represents a risk to public health due to the propagation of microorganisms through milk. Staphylococcus spp. are considered the microorganisms that cause the greatest losses in milk production, being that Staphylococcus aureus is the pathogen of major importance because they present high resistence to antimicrobials. Empirical treatment, without prior identification of the pathogens and their resistance profile, may contribute to the emergence of multidrug-resistant strains and risk the efficiency of the antimicrobial. In that scenery, the study aimed to evaluate the resistance profile of Staphylococcus spp. against some antimicrobials used in the treatment of cows with clinical mastitis. The study was conducted on a property in the state of São Paulo from January 2011 to June 2012. We evaluated 29 lactating cows that present clinical mastitis in, at least, one mammary quarter. The diagnosis of clinical mastitis was performed by evaluating the clinical signs and also by Tamis test. Samples of milk from mammary quarters were collected aseptically in sterile tubes for microbiological evaluation. Microorganisms were isolated on sheep blood agar 5% and Sabouraud agar with chloramphenicol. The sensitivity profile of Staphylococcus spp. to the antibiotics ampicillin, cephalexin, ceftiofur, cefaclor, gentamicin, kanamycin, neomycin, penicillin G and oxacillin, was tested by disk diffusion test on Mueller-Hinton agar. From a total of 106 samples of milk analyzed, 64 (60.38% presented microbiological growth, being observed isolation of Streptococcus spp. 29 (34.52%, Staphylococcus spp. 28 (33.33%, Corynebacterium spp. 17 (20.24%, filamentous fungi 4 (4.76%, yeast 4 (4

  14. A clinical Acanthamoeba isolate harboring two distinct bacterial endosymbionts.

    Science.gov (United States)

    Müller, Anneliese; Walochnik, Julia; Wagner, Martin; Schmitz-Esser, Stephan

    2016-10-01

    Acanthamoebae feed on bacteria but are also frequent hosts of bacterial symbionts. Here, we describe the stable co-occurrence of two symbionts, one affiliated to the genus Parachlamydia and the other to the candidate genus Paracaedibacter (Alphaproteobacteria), within a clinical isolate of Acanthamoeba hatchetti genotype T4. We performed fluorescence in situ hybridization (FISH) and transmission electron microscopy (TEM) to describe this symbiosis. Our study adds to other reports of simultaneous co-occurrence of two symbionts within one Acanthamoeba cell. Copyright © 2016 Elsevier GmbH. All rights reserved.

  15. Comparative sensitivity of Xenopus tropicalis and Xenopus laevis as test species for the FETAX model.

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    Fort, Douglas J; Rogers, Robert L; Thomas, John H; Buzzard, Brody O; Noll, Andra M; Spaulding, Clinton D

    2004-01-01

    The use of Xenopus tropicalis as an alternative test species for the Frog Embryo Teratogenesis Assay-Xenopus (FETAX) model was evaluated. Five test substances with varying developmental toxicity potential were evaluated using the traditional FETAX (X. laevis) and a modified assay to accommodate the use of X. tropicalis. Two separate definitive concentration-response tests were performed with ethanol, semicarbazide, copper, 6-aminonicotinamide (6-AN) and atrazine. In order to evaluate the impact of culture temperature on species sensitivity, tests with X. tropicalis were performed concurrently at 27 degrees C (optimum temperature) and 23 degrees C (traditional FETAX temperature). Tests with X. laevis were performed only at 23 degrees C (optimal for X. laevis). Regardless of culture temperature, tests with X. laevis and X. tropicalis indicated that each of the compounds possessed teratogenic potential: semicarbazide>6-AN>atrazine approximately copper>ethanol. Results from these studies indicated that these two species responded similarly to the test compounds. Xenopus tropicalis was somewhat less sensitive to 6-AN, semicarbizide and atrazine when tested at 27 degrees C than at 23 degrees C. Ethanol, copper and atrazine were reasonably equipotent in X. tropicalis and X. laevis in terms of teratogenic response (EC50 for malformation), whereas 6-AN and semicarbizide were less potent in X. tropicalis than in X. laevis. No substantial differences (order of magnitude) in potency were observed between X. laevis and X. tropicalis with any of the test materials evaluated. Malformation syndromes induced in both species were similar in X. tropicalis and X. laevis. These results suggested that X. tropicalis could be used effectively as a test organism for the FETAX model.

  16. Antibiotic Resistance in Staphylococcus aureus Strains Isolated from Clinical Specimens

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    M. Sirin

    2016-04-01

    Full Text Available Aim: The aim of this study was to determine the antibiotic susceptibilities of S.aureus strains isolated from various clinical specimens between the years 2011-2014 and to investigate the changes of these susceptibilities over the years. Material and Method: Identification and antibiotic susceptibility testing of the strains were performed by Vitek 2 compact automated system (bioMérieux, France. The strains found to be intermediate susceptible to vancomycin and teicoplanin were also tested by E-test method. Results: S.aureus strains (n=1442 were most commonly isolated from wound, urine and blood samples. The isolation rates of methicillin-resistant S.aureus (MRSA in hospitalized patients were significantly higher than the isolation rates of MRSA in outpatients. All strains were susceptible to vancomycin, teicoplanin, linezolid and tigecycline. The total of four years resistance rates of MRSA strains to erythromycin, clindamycin, ciprofloxacin, moxifloxacin, gentamicin, co-trimoxazole, fusidic acid were significantly higher than the resistance rates of methicillin-sensitive S.aureus (MSSA. The changes in the rates of antibiotic resistance were not statistically significant in MSSA strains over the years, and statistically significant decrease was found in erythromycin, clindamycin, ciprofloxacin, moxifloxacin and gentamicin resistance in MRSA strains. Discussion: Glycopeptides, linezolid and tigecycline were the most effective antibiotics against S.aureus strains. It was considered as necessary to detect antimicrobial resistance profiles by effective surveillance studies and monitor the changes occurred over the years in order to prevent the development of resistance and control of infections.

  17. In vitro antimicrobial susceptibility in clinical isolates of Enterococcus species

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    Calderón-Jaimes Ernesto

    2003-01-01

    Full Text Available OBJECTIVE: To describe the antimicrobial activity of several antimicrobial agents against 97 clinical significant isolates of Enterococcus spp. MATHERIAL AND METHODS: During a 2-year prospective study at Instituto Nacional de Pediatria (National Institute of Pediatrics in Mexico City. Ninety seven strains of Enterococcus spp. (60 E. faecalis and 37 E. faecium were tested against 11 antibiotics. Susceptibility tests were performed with agar, according to the standards of the sNational Committee for Clinical Laboratory Standards (NCCLS. Isolates were screened for high-level resistance (HLR to beta-lactams, aminoglycosides, glycopeptides and other antibiotics, as well as for vancomycin-phenotypes. Differences between proportions were evaluated with chi2 of Fisher exact fest. RESULTS: Overall resistance rates to the antibiotics tested were: 17/97 (17.5% to penicillin, ampicillin, amoxicillin-clavulanate and imipenem. There was neither HLR nor beta-lactamase production; 74/97 (48.4% were resistant to erythromycin; 60% to ciprofloxacin; 31/97 (32% to gentamicin, and 55/97 (56.7% to streptomycin. Seven strains were vancomycin-resistant enterococci (VRE, all of them identified as E. faecium; 5/7 with Van A and 2/7 with Van B phenotypes. All the isolates were susceptible to linezolid. The difference in susceptibility among species was significant. CONCLUSIONS: Mutidrug-resistant enterococci is a real problem and continuous surveillance is necessary. The microbiology laboratory is the first line of defense against the spread of multiantibiotic-resistan enterococci in the hospital environment . All the strains recovered should be tested for susceptibility to ampicillin, streptomycin, gentamicin and glycopeptides.

  18. In vitro antimicrobial susceptibility in clinical isolates of Enterococcus species.

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    Calderón-Jaimes, Ernesto; Arredondo-García, José Luis; Aguilar-Ituarte, Felipe; García-Roca, Pilar

    2003-01-01

    To describe the antimicrobial activity of several antimicrobial agents against 97 clinical significant isolates of Enterococcus spp. During a 2-year prospective study at Instituto Nacional de Pediatria (National Institute of Pediatrics) in Mexico City. Ninety seven strains of Enterococcus spp. (60 E faecalis and 37 E. faecium) were tested against 11 antibiotics. Susceptibility tests were performed with agar, according to the standards of the sNational Committee for Clinical Laboratory Standards (NCCLS). Isolates were screened for high-level resistance (HLR) to beta-lactams, aminoglycosides, glycopeptides and other antibiotics, as well as for vancomycin-phenotypes. Differences between proportions were evaluated with chi 2 of Fisher exact fest. Overall resistance rates to the antibiotics tested were: 17/97 (17.5%) to penicillin, ampicillin, amoxicillin-clavulanate and imipenem. There was neither HLR nor beta-lactamase production; 74/97 (48.4%) were resistant to erythromycin; 60% to ciprofloxacin; 31/97 (32%) to gentamicin, and 55/97 (56.7%) to streptomycin. Seven strains were vancomycin-resistant enterococci (VRE), all of them identified as E. faecium; 5/7 with Van A and 2/7 with Van B phenotypes. All the isolates were susceptible to linezolid. The difference in susceptibility among species was significant. Mutidrug-resistant enterococci is a real problem and continuous surveillance is necessary. The microbiology laboratory is the first line of defense against the spread of multiantibiotic-resistan enterococci in the hospital environment. All the strains recovered should be tested for susceptibility to ampicillin, streptomycin, gentamicin and glycopeptides. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.

  19. Humoral and cellular immune responses to Blomia tropicalis and concanavalin A-binding fractions in atopic patients

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    R. Alves

    2008-09-01

    Full Text Available Blomia tropicalis, Dermatophagoides pteronyssinus and D. farinae are prevalent house dust mites. Concanavalin A-binding components derived from B. tropicalis (Bt-ConA extract are highly immunogenic in allergic diseases. The aim of the present study was to evaluate the humoral and cellular immune responses to B. tropicalis in mite-sensitized patients. A total of 137 patients with allergic rhinitis with/without asthma and 109 non-atopic subjects were selected and analyzed by the skin prick test, and for total serum IgE and specific IgE levels to both Bt-total and Bt-ConA extracts, their proliferative response and cytokine (IFN-γ and IL-5 production by peripheral blood mononuclear cells (PBMC stimulated with both extracts. Skin prick test showed that 70% of the patients were sensitized to Bt (Bt+ and similar levels of specific IgE to Bt-total and Bt-ConA extracts were demonstrable in Bt+ patients. Significant PBMC proliferation was observed in response to Bt-total extract in Bt+, but not in Bt- patients and non-atopic subjects (P < 0.001. Bt-ConA extract induced increased proliferative responses in all patient groups compared to medium alone (P < 0.05, but these responses were significantly decreased in the presence of the mannopyranoside ConA inhibitor (P < 0.05. Significant IFN-γ production was observed after Bt-ConA stimulation of Bt+ patients (P < 0.05, while Bt-total extract had no effect. IL-5 production was consistently detected in Bt+ patients after allergen-specific stimulation or with no stimulus, indicating that PBMC from allergic patients are prone to produce Th2 profile cytokines, spontaneously or inductively by allergen restimulation. These data showed that ConA-binding components isolated from B. tropicalis may contain relevant antigens that are involved in both humoral and cellular immune responses. However, without an additional purification procedure to eliminate the residual contamination with ConA, its use in immunotherapeutic

  20. Candida tropicalis endocarditis: Treatment in a resource-poor setting

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    Kumar Prashant

    2010-01-01

    Full Text Available Fungal endocarditis (FE is rare in children and does not usually occur in structurally normal hearts. The commonest causative agent is Candida albicans. We report a 5-year-old female child presenting with high-grade fever and cardiac failure. Anemia, leukocytosis and high CRP were found, but bacterial blood culture was sterile. There was no response to antimicrobial agents. Two-dimensional echocardiography revealed a large heterogeneous mass attached to the right ventricle and tricuspid valve. Provisional diagnosis of FE was made, which was confirmed by growth of Candida tropicalis in blood culture. Liposomal amphotericin B was started, followed by radical curative surgery including excision of the entire vegetation with total tricuspid valve excision. Histopathology and culture of the resected vegetation confirmed the diagnosis. The patient was given antifungal therapy for a total of 7 weeks, including 2 weeks of post-operative treatment, following which she was afebrile.

  1. Vibrio injenensis sp. nov., isolated from human clinical specimens.

    Science.gov (United States)

    Paek, Jayoung; Shin, Jeong Hwan; Shin, Yeseul; Park, In-Soon; Kim, Hongik; Kook, Joong-Ki; Kang, Seok-Seong; Kim, Dae-Soo; Park, Kun-Hyang; Chang, Young-Hyo

    2017-01-01

    Vibrio species are well known as motile, mostly oxidase-positive, facultative anaerobic Gram-negative bacteria. They are abundant in aquatic environments and are a common cause of human infections including diarrhea, soft tissue diseases, and bacteremia. Here, two Gram-negative bacteria, designated M12-1144 T and M12-1181, were isolated from human clinical specimens and identified using a polyphasic taxonomic approach. Phylogenetic study based on 16S rRNA gene sequence analysis revealed that the isolates belong to the genus Vibrio, and are closely related to Vibrio metschnikovii KCTC 32284 T (98.3%) and Vibrio cincinnatiensis KCTC 2733 T (97.8%). The major fatty acids were summed feature 3 (C 16:1 ω7c/C 16:1 ω6c, 38.0%), C 16:0 (23.0%), and summed feature 8 (C 18:1 ω7c or C 18:1 ω6c, 19.3%) and major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. The G + C content of the genomic DNA was determined to be 44.1 mol%. DNA-DNA relatedness between the two newly isolated strains and V. metschnikovii KCTC 32284 T and V. cincinnatiensis KCTC 2733 T was between 42.6 to 47.5%. The similarities of genome-to-genome distance between M12-1144 T and related species ranged from 18.4-54.8%. Based on these results, a new species of the genus Vibrio, Vibrio injenensis is proposed. The type strain is M12-1144 T (=KCTC 32233 T  =JCM 30011 T ).

  2. Cognitive impairment in patients with clinically isolated syndrome

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    Carolina Fiorin Anhoque

    Full Text Available ABSTRACT Cognitive abnormalities have been extensively studied in Multiple Sclerosis (MS. However, little is known about the cognitive involvement in patients with Clinically Isolated Syndrome (CIS. Objective: This study aimed to investigate cognitive impairment in patients with CIS compared with healthy subjects. Methods: 18 CIS patients and 18 controls were subjected to the Wechsler memory scale, Rey Auditory Verbal Learning, Rey Complex Figure, Paced Auditory Serial Addition, Digit Span, verbal fluency, Stroop color card test, D2, and Digit Symbol tests. Results: CIS patients had significantly worse performance on the Paced Auditory Serial Addition Test (PASAT 2 seconds (P=0.009 and on verbal fluency tests (P=0.0038 than controls. Conclusion: CIS patients had worse cognitive performance than controls on neuropsychological tests evaluating executive functioning.

  3. Optimization of phenol degradation by Candida tropicalis Z-04 using Plackett-Burman design and response surface methodology.

    Science.gov (United States)

    Zhou, Jiangya; Yu, Xiaojuan; Ding, Cong; Wang, Zhiping; Zhou, Qianqian; Pao, Hao; Cai, Weimin

    2011-01-01

    Statistical experimental designs were used to optimize the process of phenol degradation by Candida tropicalis Z-04, isolated from phenol-degrading aerobic granules. The most important factors influencing phenol degradation (p Plackett-Burman design with 11 variables, were yeast extract, phenol, inoculum size, and temperature. Steepest ascent method was undertaken to determine the optimal regions of these four significant factors. Central composite design (CCD) and response surface analysis were adopted to further investigate the mutual interactions between these variables and to identify their optimal values that would generate maximum phenol degradation. The analysis results indicated that interactions between yeast extract and temperature, phenol and temperature, inoculum size and temperature affected the response variable (phenol degradation) significantly. The predicted results showed that the maximum removal efficiency of phenol (99.10%) could be obtained under the optimum conditions of yeast extract 0.41 g/L, phenol 1.03 g/L, inoculum size 1.43% (V/V) and temperature 30.04 degrees C. These predicted values were further verified by validation experiments. The excellent correlation between predicted and experimental values confirmed the validity and practicability of this statistical optimum strategy. This study indicated the excellent ability of C. tropicalis Z-04 in degrading high-strength phenol. Optimal conditions obtained in this experiment laid a solid foundation for further use of this microorganism in the treatment of high-strength phenol effluents.

  4. RESPONSES OF OYSTERS AND THEIR HEMOCYTES TO CLINICAL AND ENVIRONMENTAL ISOLATES OF VIBRIO PARAHAEMOLYTICUS

    Science.gov (United States)

    Interactions of Vibrio parahaemolyticus with oysters and oyster hemocytes were studied using three environmental isolates (1094, 1163 and ATCC 17802) and three clinical isolates (2030, 2062, 2107). Clinical isolates were from patients who became ill during the June 1998 food pois...

  5. Identification of Clinical Isolates of Candida using Duplex PCR

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    Homeyra Babaei

    2016-11-01

    Full Text Available Abstract Background: Candida albicans is still the main etiologic agent of candidiasis. However, infections of non-albicans Candida species are increasing. Candida dubliniensis is similar to C. albicans phenotypically and must be identified due to the better management of infection. The aim of the present study is to defferentiate and identify Candida species by Duplex PCR for get-ting an epidemiological data of Candida species among clinical specimens. Materials and Methods: DNA was extracted using phenol-chloroform method from fresh colonies. Internal Transcribed Spacer region was amplified by polymerase chain reaction using specific primers. Based on differences of bands sizes on agarose gel electrophoresis, species were identified. Results: Ninety four out of 100 patients (49 males and 51 females had predisposing fac-tors in the present study. Diabetes (73.4%, use of antibiotic (6.3%, vitamin deficiency (4.3% were the main predisposing factors. The most specimens belonged to mouth (75%, vagina (5%, and blood (4%. All isolates were identified as C. albicans. Conclusion: Duplex PCR is a rapid and precise method for the detection and differentia-tion of Candida species carefully, and in this method, phenotypic tests like germ-tube and chla-mydoconidia production, as well as biochemical tests are not required for clinical laboratories that have limited resources and time for response to the patients, and it can replace with the traditional methods.

  6. Quantification of thigmotropism (contact sensing) of Candida albicans and Candida tropicalis.

    Science.gov (United States)

    Nikawa, H; Nishimura, H; Hamada, T; Sadamori, S

    1997-01-01

    To quantify the thigmotropism, we adapted the our previous method using a chemotaxifilter system in combination with a bioluminescent adenosine triphosphate (ATP) assay based on firefly luciferase-luciferin system and analyzed the relationship between the ability of germ tube formation and thigmotropism of C. albicans and C. tropicalis. Both the ability to form germ tube and the amount of hyphae exhibiting thigmotropism varied depending upon both the species and strains of Candida. C. albicans formed more germ tubes than C. tropicalis. A good correlation was observed between the ability to form a germ tube and the capacity for thigmotropism, and the results gave a level of significance (p < 0.05). Further, SEM observation revealed that relatively long hyphae of C. tropicalis with penetrated through the pores of filter membrane. This phenomenon may be of importance in the development of pathogenesis of C. tropicalis as well as C. albicans.

  7. Characterization of Listeria monocytogenes isolated from Ganges water, human clinical and milk samples at Varanasi, India.

    Science.gov (United States)

    Soni, Dharmendra K; Singh, Rakesh K; Singh, Durg V; Dubey, Suresh K

    2013-03-01

    Listeria monocytogenes isolated from Ganges water, human clinical and milk samples were characterized by antibiotic susceptibility, serotype identification, detection of virulence genes and ERIC- and REP-PCR fingerprint analyses. All isolates were uniformly resistant to ampicillin, except two isolates, and showed variable resistance to gentamicin, cotrimoxazole, ofloxacin, rifampicin and tetracycline. Of the 20 isolates found positive for pathogens, seven (four human and three water isolates) belong to serogroups 4b, 4d and 4e; six (one human and five water isolates) belong to serogroups 1/2c and 3c; four milk isolates belong to serogroups 1/2b and 3b; and three milk isolates belong to serogroups 1/2a and 3a. Two water isolates, all human isolates, except one (Pb1) lacking inlJ gene, and three milk isolates possess inlA, inlC, plcA, prfA, actA, hlyA and iap genes. The remaining water and milk isolates showed variable presence of inlJ, plcA, prfA, and iap genes. ERIC- and REP-PCR based analyses collectively indicated that isolates of human clinical samples belong to identical or similar clone and isolates of water and milk samples belong to different clones. Overall study demonstrates the prevalence of pathogenic L. monocytogenes species in the environmental and clinical samples. Most of the isolates were resistant to commonly used antibiotics. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Decolorization of a recalcitrant organic compound (Melanoidin by a novel thermotolerant yeast, Candida tropicalis RG-9

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    Tiwari Soni

    2012-06-01

    Full Text Available Abstract Background Sugarcane distilleries use molasses for ethanol production and generate large volume of effluent containing high biological oxygen demand (BOD and chemical oxygen demand (COD along with melanoidin pigment. Melanoidin is a recalcitrant compound that causes several toxic effects on living system, therefore, may be treated before disposal. The aim of this study was to isolate a potential thermotolerant melanoidin decolorizing yeast from natural resources, and optimized different physico-chemical and nutritional parameters. Results Total 24 yeasts were isolated from the soil samples of near by distillery site, in which isolate Y-9 showed maximum decolorization and identified as Candida tropicalis by Microbial Type Culture Collection (MTCC Chandigarh, India. The decolorization yield was expressed as the decrease in the absorbance at 475 nm against initial absorbance at the same wavelength. Uninoculated medium served as control. Yeast showed maximum decolorization (75% at 45°C using 0.2%, glucose; 0.2%, peptone; 0.05%, MgSO4; 0.01%, KH2PO4; pH-5.5 within 24 h of incubation under static condition. Decolorizing ability of yeast was also confirmed by high performance liquid chromatography (HPLC analysis. Conclusion The yeast strain efficiently decolorized melanoidin pigment of distillery effluent at higher temperature than the other earlier reported strains of yeast, therefore, this strain could also be used at industrial level for melanoidin decolorization as it tolerated a wide range of temperature and pH with very small amount of carbon and nitrogen sources.

  9. Determination of carbapenem resistance mechanism in clinical isolates of Pseudomonas aeruginosa isolated from burn patients, in Tehran, Iran

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    Akbar Mirsalehian

    2017-09-01

    Full Text Available Carbapenems are the most important therapeutic options that effect against serious infections caused by multidrug resistant Pseudomonas aeruginosa (MDR-PA isolates. Carbapenems resistant isolates of P. aeruginosa are increasing worldwide. The aim of this study was to determine the carbapenem resistance mechanisms in clinical P. aeruginosa isolates from burn patients, in Tehran, Iran. A total of 53 non-duplicated isolates of carbapenem-resistant P. aeruginosa were collected from burn patients. The presence of carbapenemase genes were determined by PCR. AmpC overproducer isolates were detected by phenotypic method. The mutation and transcription level of oprD were determined by PCR-sequencing and quantitative Real-time PCR (RT-PCR, respectively. Twenty-seven (50.9% isolates were positive for carbapenemase (blaVIM = 25 and blaIMP = 2 and showed high-level resistance to imipenem and meropenem. Twenty-eight isolates were AmpC overproducers. All isolates had a mutation in the oprD gene and down-regulation of oprD was found in 56.6% of MDR-PA isolates. Although the presence of carbapenemase is the common mechanism of resistant to carbapenem, but carbapenem resistance was found by oprD mutation-driven and the AmpC overproducing isolates in Tehran, Iran.

  10. Predictors of disability worsening in clinically isolated syndrome

    Science.gov (United States)

    Jokubaitis, Vilija G; Spelman, Tim; Kalincik, Tomas; Izquierdo, Guillermo; Grand'Maison, François; Duquette, Pierre; Girard, Marc; Lugaresi, Alessandra; Grammond, Pierre; Hupperts, Raymond; Cabrera-Gomez, José; Oreja-Guevara, Celia; Boz, Cavit; Giuliani, Giorgio; Fernández-Bolaños, Ricardo; Iuliano, Gerardo; Lechner-Scott, Jeannette; Verheul, Freek; van Pesch, Vincent; Petkovska-Boskova, Tatjana; Fiol, Marcela; Moore, Fraser; Cristiano, Edgardo; Alroughani, Raed; Bergamaschi, Roberto; Barnett, Michael; Slee, Mark; Vella, Norbert; Herbert, Joseph; Shaw, Cameron; Saladino, Maria Laura; Amato, Maria Pia; Liew, Danny; Paolicelli, Damiano; Butzkueven, Helmut; Trojano, Maria

    2015-01-01

    Objective To assess demographic, clinical, magnetic resonance imaging, and treatment exposure predictors of time to 3 or 12-month confirmed disability worsening in clinically isolated syndrome (CIS) and early multiple sclerosis (MS). Methods We utilized the MSBase Incident Study (MSBasis), a prospective cohort study of outcome after CIS. Predictors of time to first 3 and 12-month confirmed expanded disability status scale worsening were analyzed using Cox proportional hazards regression. Results About 1989 patients were analyzed, the largest seen-from-onset cohort reported to-date. A total of 391 patients had a first 3-month confirmed disability worsening event, of which 307 were sustained for 12 months. Older age at CIS onset (adjusted hazard ratio: aHR 1.17, 95% 1.06, 1.30), pyramidal (aHR 1.45, 95% CI 1.13, 1.89) and ambulation (HR 1.60, 95% CI 1.09, 2.34) system dysfunction, annualized relapse rate (aHR 1.20, 95% CI 1.18, 1.22), and lower proportion of observation time on treatment were associated with 3-month confirmed worsening. Predictors of time to 12-month sustained worsening included pyramidal system dysfunction (Hazard ratio: aHR 1.38, 95% CI 1.05, 1.83), and older age at CIS onset (aHR 1.17, 95% CI 1.04, 1.31). Greater proportion of follow-up time exposed to treatment was associated with greater reductions in the rate of worsening. Interpretation This study provides class IV evidence for a strong protective effect of disease-modifying treatment to reduce disability worsening events in patients with CIS and early MS, and confirms age and pyramidal dysfunction at onset as risk factors. PMID:26000321

  11. Utilization of carbon sources by clinical isolates of Aeromonas.

    Science.gov (United States)

    Prediger, Karoline C; Surek, Monica; Dallagassa, Cibelle B; Assis, Flávia E A; Piantavini, Mario S; Souza, Emanuel M; Pedrosa, Fábio O; Farah, Sônia M S S; Alberton, Dayane; Fadel-Picheth, Cyntia M T

    2017-04-01

    Bacteria in the genus Aeromonas are primarily aquatic organisms; however, some species can cause diseases in humans, ranging from wound infections to septicemia, of which diarrhea is the most common condition. The ability to use a variety of carbon substrates is advantageous for pathogenic bacteria. Therefore, we used Biolog GN2 microplates to analyze the ability of 103 clinical, predominantly diarrheal, isolates of Aeromonas to use various carbon sources, and we verified whether, among the substrates metabolized by these strains, there were some endogenous to the human intestine. The results indicate that Aeromonas present great diversity in the utilization of carbon sources, and that they preferentially use carbohydrates and amino acids as carbon sources. Among the carbon sources metabolized by Aeromonas in vitro, some were found to be components of intestinal mucin, including aspartic acid, glutamic acid, l-serine, galactose, N-acetyl-glucosamine, and glucose, which were used by all strains tested. Additionally, mannose, d-serine, proline, threonine, and N-acetyl-galactosamine were used by several strains. The potential to metabolize substrates endogenous to the intestine may contribute to Aeromonas' capacity to grow in and colonize the intestine. We speculate that this may help explain the ability of Aeromonas to cause diarrhea.

  12. Identification of signature volatiles to discriminate Candida albicans, glabrata, krusei and tropicalis using gas chromatography and mass spectrometry.

    Science.gov (United States)

    Hertel, Moritz; Hartwig, Stefan; Schütte, Eyke; Gillissen, Bernhard; Preissner, Robert; Schmidt-Westhausen, Andrea Maria; Paris, Sebastian; Kastner, Isabell; Preissner, Saskia

    2016-02-01

    Oral candidiasis is the most frequent fungal infection of the oral cavity. Clinical diagnoses require mycological confirmation, which is time-consuming in case of culture testing. The aim of the study was to identify signature volatiles to develop a chairside breath test to diagnose oral candidiasis. Headspaces above Candida albicans, glabrata, tropicalis, krusei cultures, and growth media as control were analysed after eight and 24 h using offline gas chromatography and mass spectrometry. The identification of signature volatiles was assisted using various microbial databases. Retrieved volatile patterns enabled Candida species discrimination in vitro. For C. albicans 3-methyl-2-butanone and styrene and for C. krusei a combination of p-xylene, 2-octanone, 2-heptanone and n-butyl acetate were found to be specific. 1-hexanol was found in C. tropicalis, but is emitted by a variety of other microorganisms. C. glabrata was characterised through the absence of these volatiles. The development of a breath test is a promising approach in confirming suspicions of oral candidiasis. To confirm the retrieved results in vivo, breath tests in affected and healthy subjects have to be performed. © 2015 Blackwell Verlag GmbH.

  13. Expression of ribosomopathy genes during Xenopus tropicalis embryogenesis.

    Science.gov (United States)

    Robson, Andrew; Owens, Nick D L; Baserga, Susan J; Khokha, Mustafa K; Griffin, John N

    2016-10-26

    Because ribosomes are ubiquitously required for protein production, it was long assumed that any inherited defect in ribosome manufacture would be embryonically lethal. However, several human congenital diseases have been found to be associated with mutations in ribosome biogenesis factors. Surprisingly, despite the global requirement for ribosomes, these "ribosomopathies" are characterized by distinct and tissue specific phenotypes. The reasons for such tissue proclivity in ribosomopathies remain mysterious but may include differential expression of ribosome biogenesis factors in distinct tissues. Here we use in situ hybridization of labeled antisense mRNA probes and ultra high temporal resolution RNA-Seq data to examine and compare expression of 13 disease associated ribosome biogenesis factors at six key stages in Xenopus tropicalis development. Rather than being ubiquitously expressed during development, mRNAs of all examined ribosome biogenesis factors were highly enriched in specific tissues, including the cranial neural crest and ventral blood islands. Interestingly, expression of ribosome biogenesis factors demonstrates clear differences in timing, transcript number and tissue localization. Ribosome biogenesis factor expression is more spatiotemporally regulated during embryonic development than previously expected and correlates closely with many of the common ribosomopathy phenotypes. Our findings provide information on the dynamic use of ribosome production machinery components during development and advance our understanding of their roles in disease.

  14. Characterisation of clinically isolated Streptococcus pyogenes from balanoposthitis patients, with special emphasis on emm89 isolates.

    Science.gov (United States)

    Hasegawa, Tadao; Hata, Nanako; Matsui, Hideyuki; Isaka, Masanori; Tatsuno, Ichiro

    2017-04-01

    Streptococcus pyogenes causes a variety of diseases, such as pharyngitis and toxic shock syndrome. In addition, this bacterium is a causative agent of balanoposthitis. To reveal the bacteriological characteristics of the isolates from balanoposthitis patients, we analysed 47 isolates. In addition, novel clade genotype emm89 S. pyogenes isolates have been reported to be spreading worldwide recently. Hence, we further analysed eight emm89 isolates. A drug susceptibility experiment was performed and emm types were determined. More detailed experiments, such as PCR analysis for the presence of virulence-associated genes and MLST analysis, were performed especially using emm89 isolates. All isolates were sensitive to ampicillin, but 34 % of the isolates were resistant to at least one antibiotic. The emm types of the isolates varied, with emm89 and emm11 being the most prevalent, but the emm1 type was not detected. The analysis of emm89 isolates revealed that drug susceptibilities varied. All isolates were negative for the hasABC gene and produced active NADase that are characteristics of novel clade genotype emm89 S. pyogenes. MLST analysis demonstrated that six isolates were of the ST101 type, the most predominant type reported thus far, but two isolates were of the ST646 type. According to the PCR analysis used to determine the presence of streptococcal pyrogenic exotoxin-related genes, the six ST101 isolates were further classified into four groups. These results suggest that balanoposthitis is caused by a variety of types of S. pyogenes, with novel clade genotype emm89 isolates playing a role in balanoposthitis infections in Japan.

  15. [Absolute or relative isolation for fissure sealants? 12-month clinical study].

    Science.gov (United States)

    Llodra Calvo, J C; Baca García, P

    1991-03-01

    The purpose of this clinical study is to analyse the effectiveness of a sealant. Rubber dam and cotton roll methods of isolation where compared with respect to the effect of isolation method on retreatment and protection from caries during 12 months. We study the cost effectiveness ratio for both methods of isolation. The results could not be substantiated any differences between two methods.

  16. Characterization of clinical and environmental Mycobacterium avium spp. isolates and their interaction with human macrophages.

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    Evelyn Guirado

    Full Text Available Members of the Mycobacterium avium complex (MAC are naturally occurring bacteria in the environment. A link has been suggested between M. avium strains in drinking water and clinical isolates from infected individuals. There is a need to develop new screening methodologies that can identify specific virulence properties of M. avium isolates found in water that predict a level of risk to exposed individuals. In this work we have characterized 15 clinical and environmental M. avium spp. isolates provided by the US Environmental Protection Agency (EPA to improve our understanding of the key processes involved in the binding, uptake and survival of these isolates in primary human macrophages. M. avium serovar 8 was predominant among the isolates studied. Different amounts and exposure of mannose-capped lipoarabinomannan (ManLAM and glycopeptidolipids (GPLs, both major mycobacterial virulence factors, were found among the isolates studied. Reference clinical isolate 104 serovar 1 and clinical isolates 11 and 14 serovar 8 showed an increased association with macrophages. Serum opsonization increased the cell association and survival at 2 h post infection for all isolates. However, only the clinical isolates 104 and 3 among those tested showed an increased growth in primary human macrophages. The other isolates varied in their survival in these cells. Thus we conclude that the amounts of cell envelope ManLAM and GPL, as well as GPL serovar specificity are not the only important bacterial factors for dictating the early interactions of M. avium with human macrophages.

  17. DIFFERENTIAL EFFECTS OF OYSTER (CRASSOSTREA VIRGINICA) DEFENSES ON CLINICAL AND ENVIRONMENTAL ISOLATES OF VIBRIO PARAHEMOLYTICUS

    Science.gov (United States)

    Three clinical (2030, 2062, and 2107) and three environmental (1094, 1163, and ATCC 17802) isolates of Vibrio parahaemolyticus were exposed to hemocytes and plasma collected from oysters (Crassostrea virginica) to determine their susceptibility to putative oyster defenses. Clinic...

  18. Clinical bacterial isolates from hospital environment as agents of ...

    African Journals Online (AJOL)

    The relationship between bacteria isolated from the hospital environment and those from wounds of operated patients was investigated to determine the causal agents of surgical site nosocomial infections. The study was carried out on bacterial species isolated from the theatre, surgical ward and patients' surgical wounds ...

  19. Phospholipase Activities in Clinical and Environmental Isolates of Acanthamoeba

    Science.gov (United States)

    Matin, Abdul

    2011-01-01

    The pathogenesis and pathophysiology of Acanthamoeba infections remain incompletely understood. Phos-pholipases are known to cleave phospholipids, suggesting their possible involvement in the host cell plasma membrane disruption leading to host cell penetration and lysis. The aims of the present study were to determine phospholipase activities in Acanthamoeba and to determine their roles in the pathogenesis of Acanthamoeba. Using an encephalitis isolate (T1 genotype), a keratitis isolate (T4 genotype), and an environmental isolate (T7 genotype), we demonstrated that Acanthamoeba exhibited phospholipase A2 (PLA2) and phospholipase D (PLD) activities in a spectrophotometry-based assay. Interestingly, the encephalitis isolates of Acanthamoeba exhibited higher phospholipase activities as compared with the keratitis isolates, but the environmental isolates exhibited the highest phospholipase activities. Moreover, Acanthamoeba isolates exhibited higher PLD activities compared with the PLA2. Acanthamoeba exhibited optimal phospholipase activities at 37℃ and at neutral pH indicating their physiological relevance. The functional role of phospholipases was determined by in vitro assays using human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier. We observed that a PLD-specific inhibitor, i.e., compound 48/80, partially inhibited Acanthamoeba encephalitis isolate cytotoxicity of the host cells, while PLA2-specific inhibitor, i.e., cytidine 5'-diphosphocholine, had no effect on parasite-mediated HBMEC cytotoxicity. Overall, the T7 exhibited higher phospholipase activities as compared to the T4. In contract, the T7 exhibited minimal binding to, or cytotoxicity of, HBMEC. PMID:21461262

  20. SUSCEPTIBILITY OF RESPIRATORY ISOLATES OF STREPTOCOCCUS PNEUMONIAE ISOLATED FROM CHILDREN HOSPITALIZED IN THE CLINICAL CENTER NIS.

    Science.gov (United States)

    Dinić, Marina M; Mladenović Antić, Snezana; Kocić, Branislava; Stanković Dordević, Dobrila; Vrbić, Miodrag; Bogdanović, Milena

    2016-01-01

    Streptococcus pneumoniae is one of the most common causes of respiratory infections. The aim was to study the susceptibility to antimicrobial agents of respiratory isolates ofStreptococcus pneumoniae obtained from hospitalized children. A total of 190 respiratory pneumococcal isolates obtained from children aged from 0 to 14 years were isolated and identified by using standard microbiological methods. Susceptibility to oxacillin, erythromycin, clindamycin, tetracycline, cotrimoxazole, ofloxacin and rifampicin was tested by disc diffusion method. Minimal inhibitory concentrations for amoxicillin and ceftriaxone were determined by means of E test. The macrolide-resistant phenotype was detected by double disc diffusion test. All tested isolates were susceptible to amoxicillin and ceftriaxone. The minimal amoxicillin concentration inhibiting the growth of 50% of isolates and of 90% of isolates was 0.50 microg/ml and 1.0 microg/ml, respectively and the minimal ceftriaxone concentration inhibiting the growth of 50% of isolates and of 90% of isolates was 0.25 microg/ml and 0.50 microg/ml, respectively. Susceptibility to erythromycin and clindamycin was observed in 21.6% and 29.47% of isolates, respectively. The resistence to macrolides-M phenotype was detected in 10.07% of isolates and constitutive macrolide-lincosamide-streptogramin phenotype (constitutive MLS phenotype) was found in 89.93% of isolates. All tested isolates were susceptible to ofloxacin and rifampicin. Amoxicillin could be the therapy of choice in pediatric practice. The macrolides should not be recommended for the empirical therapy of pneumococcal respiratory tract infection in our local area.

  1. Emergence of a colistin-resistant Escherichia coli clinical isolate harboring mcr-1 in Japan

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    Tatsuya Tada

    2017-10-01

    Full Text Available The mcr-1 is a gene encoding a phosphoethanolamine transferase, which confers resistance to colistin by transferring phosphoethanolamine to lipid A. We describe here the emergence of a colistin-resistant Escherichia coli clinical isolate harboring plasmid-mediated mcr-1 in Japan. The isolate belonged to ST5702 and is suspected to come from livestock and transmitted to human. This is the first report of a clinical isolate harboring mcr-1 in Japan.

  2. Enhancing effect of centrifugation on isolation of influenza virus from clinical specimens.

    OpenAIRE

    Seno, M; Kanamoto, Y; Takao, S; Takei, N; Fukuda, S; Umisa, H

    1990-01-01

    The use of centrifugation (700 x g, 60 min) in a plaque assay markedly increased (mean, 2.9-fold) the infectivity of all 42 influenza virus strains tested, compared with no centrifugation. Of 13 influenza virus strains isolated from 390 clinical specimens, 9 (69%) were efficiently isolated by the centrifugation assay compared with conventional culture methods. The centrifugation assay may be useful for isolating the influenza virus from clinical specimens.

  3. Saccharomyces cerevisiae: population divergence and resistance to oxidative stress in clinical, domesticated and wild isolates.

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    Stephanie Diezmann

    Full Text Available BACKGROUND: Saccharomyces cerevisiae has been associated with human life for millennia in the brewery and bakery. Recently it has been recognized as an emerging opportunistic pathogen. To study the evolutionary history of S. cerevisiae, the origin of clinical isolates and the importance of a virulence-associated trait, population genetics and phenotypic assays have been applied to an ecologically diverse set of 103 strains isolated from clinics, breweries, vineyards, fruits, soil, commercial supplements and insect guts. METHODOLOGY/PRINCIPAL FINDINGS: DNA sequence data from five nuclear DNA loci were analyzed for population structure and haplotype distribution. Additionally, all strains were tested for survival of oxidative stress, a trait associated with microbial pathogenicity. DNA sequence analyses identified three genetic subgroups within the recombining S. cerevisiae strains that are associated with ecology, geography and virulence. Shared alleles suggest that the clinical isolates contain genetic contribution from the fruit isolates. Clinical and fruit isolates exhibit high levels of recombination, unlike the genetically homogenous soil isolates in which no recombination was detected. However, clinical and soil isolates were more resistant to oxidative stress than any other population, suggesting a correlation between survival in oxidative stress and yeast pathogenicity. CONCLUSIONS/SIGNIFICANCE: Population genetic analyses of S. cerevisiae delineated three distinct groups, comprising primarily the (i human-associated brewery and vineyard strains, (ii clinical and fruit isolates (iii and wild soil isolates from eastern U.S. The interactions between S. cerevisiae and humans potentiate yeast evolution and the development of genetically, ecologically and geographically divergent groups.

  4. Isolation of chlorhexidine-resistant Pseudomonas aeruginosa from clinical lesions.

    OpenAIRE

    Nakahara, H; Kozukue, H

    1982-01-01

    The chlorhexidine resistance of 317 strains of Pseudomonas aeruginosa isolated from hospital patients was determined. The distribution pattern of their susceptibility to chlorhexidine clearly revealed two peaks, and the frequency of resistance to chlorhexidine was 84.2%.

  5. Culture media profoundly affect Candida albicans and Candida tropicalis growth, adhesion and biofilm development.

    Science.gov (United States)

    Weerasekera, Manjula M; Wijesinghe, Gayan K; Jayarathna, Thilini A; Gunasekara, Chinthika P; Fernando, Neluka; Kottegoda, Nilwala; Samaranayake, Lakshman P

    2016-11-01

    As there are sparse data on the impact of growth media on the phenomenon of biofilm development for Candida we evaluated the efficacy of three culture media on growth, adhesion and biofilm formation of two pathogenic yeasts, Candida albicans and Candida tropicalis. The planktonic phase yeast growth, either as monocultures or mixed cultures, in sabouraud dextrose broth (SDB), yeast nitrogen base (YNB), and RPMI 1640 was compared, and adhesion as well as biofilm formation were monitored using MTT and crystal violet (CV) assays and scanning electron microscopy. Planktonic cells of C. albicans, C. tropicalis and their 1:1 co-culture showed maximal growth in SDB. C. albicans/C. tropicalis adhesion was significantly facilitated in RPMI 1640 although the YNB elicited the maximum growth for C. tropicalis. Similarly, the biofilm growth was uniformly higher for both species in RPMI 1640, and C. tropicalis was the slower biofilm former in all three media. Scanning electron microscopy images tended to confirm the results of MTT and CV assay. Taken together, our data indicate that researchers should pay heed to the choice of laboratory culture media when comparing relative planktonic/biofilm growth of Candida. There is also a need for standardisation of biofilm development media so as to facilitate cross comparisons between laboratories.

  6. Presumptive identification of Candida species other than C. albicans, C. krusei, and C. tropicalis with the chromogenic medium CHROMagar Candida

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    Horvath Lynn L

    2006-01-01

    Full Text Available Abstract Background CHROMagar Candida (CaC is increasingly being reported as a medium used to differentiate Candida albicans from non-albicans Candida (NAC species. Rapid identification of NAC can assist the clinician in selecting appropriate antifungal therapy. CaC is a differential chromogenic medium designed to identify C. albicans, C. krusei, and C. tropicalis based on colony color and morphology. Some reports have proposed that CaC can also reliably identify C. dubliniensis and C. glabrata. Methods We evaluated the usefulness of CaC in the identification of C. dubliniensis, C. famata, C. firmetaria, C. glabrata, C. guilliermondii, C. inconspicua, C. kefyr, C. lipolytica, C. lusitaniae, C. norvegensis, C. parapsilosis, and C. rugosa. Results Most NAC produced colonies that were shades of pink, lavender, or ivory. Several isolates of C. firmetaria and all C. inconspicua produced colonies difficult to differentiate from C. krusei. Most C. rugosa isolates produced unique colonies with morphology like C. krusei except in a light blue-green color. C. glabrata isolates produced small dark violet colonies that could be differentiated from the pink and lavender colors produced by other species. All seventeen isolates of C. dubliniensis produced green colonies similar to those produced by C. albicans. Conclusion C. glabrata and C. rugosa appear distinguishable from other species using CaC. Some NAC, including C. firmetaria and C. inconspicua, could be confused with C. krusei using this medium.

  7. Heterogeneity of plasmids determining high-level resistance to gentamicin in clinical isolates of Streptococcus faecalis.

    OpenAIRE

    Zervos, M J; Mikesell, T S; Schaberg, D R

    1986-01-01

    Between November 1981 and October 1984, 48 of 3,458 clinical isolates of Streptococcus faecalis at the University of Michigan Hospital showed high-level (greater than 2,000 micrograms/ml) resistance to gentamicin, as well as to all other clinically available aminoglycosides. Thirteen percent of clinical isolates in the University of Michigan Hospital currently demonstrate this level of resistance. Transfer of resistance to a plasmid-free streptococcal recipient was observed in filter matings ...

  8. Predicting outcome in clinically isolated syndrome using machine learning

    Directory of Open Access Journals (Sweden)

    V. Wottschel

    2015-01-01

    Machine-learning-based classifications can be used to provide an “individualised” prediction of conversion to MS from subjects' baseline scans and clinical characteristics, with potential to be incorporated into routine clinical practice.

  9. Clinical, imaging and histopathological features of isolated CNS lymphomatoid granulomatosis

    International Nuclear Information System (INIS)

    Patil, Anil Kumar; Alexander, Mathew; Nair, Bijesh; Chacko, Geeta; Mani, Sunithi; Sudhakar, Sniya

    2015-01-01

    Lymphomatoid granulomatosis is a rare systemic angiocentric/angiodestructive, B cell lymphoproliferative disorder. Central nervous system involvement occurs as part of systemic disease. Isolated central nervous system disease is rare with only few case reports. A 53-year-old male presented with progressive cognitive decline, extrapyramidal features, and altered sensorium with seizures over the last 4 years. His magnetic resonance imaging (MRI) of brain showed multiple small enhancing nodules in subependymal/ependymal regions and along the vessels. Brain biopsy showed atypical lymphohistiocytic infiltrate suggestive of lymphomatoid granulomatosis. There was no evidence of systemic disease; thus, isolated central nervous system lymphomatoid granulomatosis was diagnosed

  10. Pilot morpholino screen in Xenopus tropicalis identifies a novel gene involved in head development.

    Science.gov (United States)

    Kenwrick, Sue; Amaya, Enrique; Papalopulu, Nancy

    2004-02-01

    The diploid frog X. tropicalis has recently been adopted as a model genetic system, but loss-of-function screens in Xenopus have not yet been performed. We have undertaken a pilot functional knockdown screen in X. tropicalis for genes involved in nervous system development by injecting antisense morpholino (MO) oligos directed against X. tropicalis mRNAs. Twenty-six genes with primary expression in the nervous system were selected as targets based on an expression screen previously conducted in X. laevis. Reproducible phenotypes were observed for six and for four of these, a second MO gave a similar result. One of these genes encodes a novel protein with previously unknown function. Knocking down this gene, designated pinhead, results in severe microcephaly, whereas, overexpression results in macrocephaly. Together with the early embryonic expression in the anterior neural plate, these data indicate that pinhead is a novel gene involved in controlling head development. Copyright 2003 Wiley-Liss, Inc.

  11. Membrane-bound alcohol dehydrogenase is essential for glyceric acid production in Acetobacter tropicalis.

    Science.gov (United States)

    Habe, Hiroshi; Sato, Shun; Fukuoka, Tokuma; Kitamoto, Dai; Yakushi, Toshiharu; Matsushita, Kazunobu; Sakaki, Keiji

    2011-01-01

    Acetobacter tropicalis NBRC16470 can produce highly enantiomerically pure D-glyceric acid (D-GA; >99 % enantiomeric excess) from glycerol. To investigate whether membrane-bound alcohol dehydrogenase (mADH) is involved in GA production in A. tropicalis, we amplified part of the gene encoding mADH subunit I (adhA) using polymerase chain reaction and constructed an adhA-disrupted mutant of A. tropicalis (ΔadhA). Because ΔadhA did not produce GA, we confirmed that mADH is essential for the conversion of glycerol to GA. We also cloned and sequenced the entire region corresponding to adhA and adhB, which encodes mADH subunit II. The sequences showed high identities (84-86 %) with the equivalent mADH subunits from other Acetobacter spp.

  12. Identification of Stenotrophomonas maltophilia strains isolated from environmental and clinical samples: a rapid and efficient procedure.

    Science.gov (United States)

    Pinot, C; Deredjian, A; Nazaret, S; Brothier, E; Cournoyer, B; Segonds, C; Favre-Bonté, S

    2011-11-01

    Aim of the study is to identify accurately Stenotrophomonas maltophilia isolates recovered from environmental and clinical samples. Recovery of Sten. maltophilia-like isolates from soil samples using the vancomycin, imipenem, amphotericin B (VIA) selective agar medium enabled distinction of various morphotype colonies. A set of soil and clinical isolates was tested for species identification using different methods. 16S rDNA analyses showed the dark green with a blue halo morphotype to be typical Sten. maltophilia strains. The API-20NE, Vitek-2 and Biolog phenotypic analyses typically used for the identification of clinical isolates did not perform well on these soil isolates. The species-specific PCR screening targeting Sten. maltophilia 23S rDNA and the multiplex smeD/ggpS PCR, differentiating Sten. maltophilia from Stenotrophomonas rhizophila, were tested for improvement of these identification schemes. The latter multiplex PCR identified all isolates tested in this study, whatever be their origin. Isolation on VIA medium and confirmation of Sten. maltophilia species membership by smeD PCR is proposed to identify environmental and clinical isolates of Sten. maltophilia. The proposed approach enables isolation and identification of Sten. maltophilia from different environments in an easy and rapid way. This approach will be useful to accurately manage studies on the abundance and distribution of Sten. maltophilia in hospital and nonhospital environments. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  13. Mitochondrial DNA fingerprinting of Acanthamoeba spp. isolated from clinical and environmental sources.

    Science.gov (United States)

    Gautom, R K; Lory, S; Seyedirashti, S; Bergeron, D L; Fritsche, T R

    1994-04-01

    Restriction fragment length polymorphism analysis of mitochondrial DNA (mtDNA fingerprinting) was evaluated as an epidemiologic tool for identifying potential reservoirs of Acanthamoeba infection. Fingerprints for 15 clinical isolates recovered by our affiliated laboratories were compared with those for 25 environmental isolates from western Washington State and 10 American Type Culture Collection (ATCC) strains. Seven different fingerprint groups emerged from the analysis of clinical isolates with six selected restriction enzymes (BamHI, BglII, EcoRI, HindIII, KpnI, and SalI). Fourteen (56%) environmental and 4 (40%) ATCC isolates displayed fingerprints similar to those of clinical isolates. In all, five of the seven groups contained one or more environmental and/or ATCC isolates. Comparisons with published mtDNA fingerprints for Acanthamoeba isolates showed that two groups have counterparts in Europe and Japan and in Europe and Australia. The inclusion of environmental isolates demonstrated that the most common clinical isolates do have counterparts readily recoverable from the surrounding environment and that some of these counterparts appear to be geographically widespread.

  14. Detection of efflux pump activity among clinical isolates of ...

    African Journals Online (AJOL)

    Purpose: To detect efflux pump activity (EPA) and screening a suspected efflux pump inhibitor (EPI) [1- (3-(trifluoromethyl)benzyl]-piperazine (TFMBP)], which could help in reducing multi-drug resistance (MDR). Methods: Eighteen isolates, viz, 14 S. aureus, 2 S. lentus, 1 S. xylosus and 1 Micrococcus species from various ...

  15. Molecular phylogeny of Escherichia coli isolated from clinical ...

    African Journals Online (AJOL)

    A, B1, B2 and D). Strains of these groups differ in their phenotypic characteristics, including the ability to use certain sugars, antibiotic resistance profiles and growth rate-temperature relationships. A total of 45 E. coli isolates were obtained from ...

  16. Molecular phylogeny of Escherichia coli isolated from clinical ...

    African Journals Online (AJOL)

    lames

    2011-11-09

    A, B1, B2 and D). Strains of these groups differ in their phenotypic characteristics, including the ability to use certain sugars, antibiotic resistance profiles and growth rate-temperature relationships. A total of 45 E. coli isolates ...

  17. Prevalence of bla SHV genes in clinical isolates of Klebsiella ...

    African Journals Online (AJOL)

    Five bacterial strains (4 Klebsiella pneumoniae and 1 Escherichia coli) representative of pathogenic species and resistant to β-lactam antibiotics are investigated to isolate the genes responsible of β--lactamase activity. The use of engineering techniques enables us to show the widespread of blaSHV genes particularly in ...

  18. Genome Analysis of Environmental and Clinical P. aeruginosa Isolates from Sequence Type-1146

    Science.gov (United States)

    Sánchez, David; Gomila, Margarita; Bennasar, Antonio; Lalucat, Jorge; García-Valdés, Elena

    2014-01-01

    The genomes of Pseudomonas aeruginosa isolates of the new sequence type ST-1146, three environmental (P37, P47 and P49) and one clinical (SD9) isolates, with differences in their antibiotic susceptibility profiles have been sequenced and analysed. The genomes were mapped against P. aeruginosa PAO1-UW and UCBPP-PA14. The allelic profiles showed that the highest number of differences were in “Related to phage, transposon or plasmid” and “Secreted factors” categories. The clinical isolate showed a number of exclusive alleles greater than that for the environmental isolates. The phage Pf1 region in isolate SD9 accumulated the highest number of nucleotide substitutions. The ORF analysis of the four genomes assembled de novo indicated that the number of isolate-specific genes was higher in isolate SD9 (132 genes) than in isolates P37 (24 genes), P47 (16 genes) and P49 (21 genes). CRISPR elements were found in all isolates and SD9 showed differences in the spacer region. Genes related to bacteriophages F116 and H66 were found only in isolate SD9. Genome comparisons indicated that the isolates of ST-1146 are close related, and most genes implicated in pathogenicity are highly conserved, suggesting a genetic potential for infectivity in the environmental isolates similar to the clinical one. Phage-related genes are responsible of the main differences among the genomes of ST-1146 isolates. The role of bacteriophages has to be considered in the adaptation processes of isolates to the host and in microevolution studies. PMID:25329302

  19. Genome analysis of environmental and clinical P. aeruginosa isolates from sequence type-1146.

    Directory of Open Access Journals (Sweden)

    David Sánchez

    Full Text Available The genomes of Pseudomonas aeruginosa isolates of the new sequence type ST-1146, three environmental (P37, P47 and P49 and one clinical (SD9 isolates, with differences in their antibiotic susceptibility profiles have been sequenced and analysed. The genomes were mapped against P. aeruginosa PAO1-UW and UCBPP-PA14. The allelic profiles showed that the highest number of differences were in "Related to phage, transposon or plasmid" and "Secreted factors" categories. The clinical isolate showed a number of exclusive alleles greater than that for the environmental isolates. The phage Pf1 region in isolate SD9 accumulated the highest number of nucleotide substitutions. The ORF analysis of the four genomes assembled de novo indicated that the number of isolate-specific genes was higher in isolate SD9 (132 genes than in isolates P37 (24 genes, P47 (16 genes and P49 (21 genes. CRISPR elements were found in all isolates and SD9 showed differences in the spacer region. Genes related to bacteriophages F116 and H66 were found only in isolate SD9. Genome comparisons indicated that the isolates of ST-1146 are close related, and most genes implicated in pathogenicity are highly conserved, suggesting a genetic potential for infectivity in the environmental isolates similar to the clinical one. Phage-related genes are responsible of the main differences among the genomes of ST-1146 isolates. The role of bacteriophages has to be considered in the adaptation processes of isolates to the host and in microevolution studies.

  20. Bilateral polymicrobial osteomyelitis with Candida tropicalis and Candida krusei: a case report and an updated literature review

    DEFF Research Database (Denmark)

    Kaldau, Niels Christian; Brorson, Stig; Jensen, Poul Einar

    2012-01-01

    We present a case of bilateral polymicrobial osteomyelitis with Candida tropicalis and Candida krusei, and review the literature on Candida osteomyelitis.......We present a case of bilateral polymicrobial osteomyelitis with Candida tropicalis and Candida krusei, and review the literature on Candida osteomyelitis....

  1. In vitro activity of antiamoebic drugs against clinical isolates of Entamoeba histolytica and Entamoeba dispar

    Directory of Open Access Journals (Sweden)

    Mahajan Ramesh

    2004-12-01

    Full Text Available Abstract Background Amoebiasis is a major public health problem in tropical and subtropical countries. Although a number of antiamoebic agents are used for its treatment, yet the susceptibility data on clinical isolates of Entamoeba histolytica and Entamoeba dispar are not available. Therefore, the present study was aimed to assess the in vitro susceptibility of clinical isolates of E. histolytica and E. dispar to metronidazole, chloroquine, emetine and tinidazole. Methods A total of 45 clinical isolates (15 E. histolytica and 30 E. dispar were maintained in polyxenic cultures followed by monoxenic cultures. In vitro drug sensitivity (IC50 of clinical isolates and standard reference strain of E. histolytica (HM1: IMSS was assessed by nitro blue tetrazolium (NBT reduction assay after exposure to various concentrations of each drug. Results The results showed that all clinical isolates had a higher IC50 compared to reference strain to all the four drugs. E. histolytica isolates appeared to be more susceptible [IC50 (μm 13.2,26.3,31.2 and 12.4] compared to E. dispar isolates [IC50(μm 15.6,28.9,32.8 and 13.2] and the reference strain of E. histolytica [IC50 (��m 9.5, 15.5, 29.9 and 10.2] to the metronidazole, chloroquine, emetine and tinidazole respectively. Conclusions The results indicate that till date, Entamoeba isolates in India do not seem to be resistant to the commonly used antiamoebic drugs.

  2. Candida tropicalis CE017: a new Brazilian enzymatic source for the bioreduction of aromatic prochiral ketones

    International Nuclear Information System (INIS)

    Vieira, Gizelle A.B.; Araujo, Daniel M. de Freitas; Lemos, Telma L.G.; Mattos, Marcos Carlos de; Oliveira, Maria da Conceicao F. de; Melo, Vania M.M.; Gonzalo, Gonzalo de; Gotor-Fernandez, Vicente; Gotor, Vicente

    2010-01-01

    The reactivity and stereoselectivity showed by a new strain of Candida tropicalis in the reduction of prochiral ketones have been compared with the ones previously attained in our laboratory using microorganisms from the Brazilian biodiversity. In this manner, Candida tropicalis has demonstrated its versatility as stereoselective agent in the bioreduction of a series of aromatic ketones. These prochiral compounds were converted into their corresponding optically alcohols with moderate to excellent stereopreference depending on the substrate structure. Among ketones tested, nitroacetophenones were enzymatically reduced to enantiopure (S)-alcohol with complete conversion. (author)

  3. Prevalence and molecular characterization of clinical isolates of Escherichia coli expressing an AmpC phenotype

    DEFF Research Database (Denmark)

    Jørgensen, Rikke Lind; Nielsen, Jesper Boye; Friis-Møller, Alice

    2010-01-01

    OBJECTIVES: To establish the prevalence of the AmpC beta-lactamase phenotype in clinical isolates of Escherichia coli and characterize the genetic resistance mechanisms causing the observed phenotype. METHODS: Clinical E. coli (n = 74) with reduced susceptibility to third-generation cephalosporins...... with hyperproduction and gene mutations associated with extended-spectrum AmpC (ESAC) beta-lactamase activity. RESULTS: Twenty-four isolates exhibited a positive AmpC disc test. IEF confirmed AmpC expression in all isolates except one. Four isolates contained a bla(CMY-2) gene. These were not clonally related....... Sequencing of ampC showed that most isolates were not clonally related. CONCLUSIONS: E. coli expressing an AmpC phenotype occur sporadically and cause significant resistance to cephalosporins. The majority of these are hyperproducing chromosomal ampC although some isolates have acquired pAmpC....

  4. Mycobacterium tuberculosis Isolates from Single Outpatient Clinic in Panama City Exhibit Wide Genetic Diversity

    Science.gov (United States)

    Sambrano, Dilcia; Correa, Ricardo; Almengor, Pedro; Domínguez, Amada; Vega, Silvio; Goodridge, Amador

    2014-01-01

    Understanding Mycobacterium tuberculosis biodiversity and transmission is significant for tuberculosis control. This short report aimed to determine the genetic diversity of M. tuberculosis isolates from an outpatient clinic in Panama City. A total of 62 M. tuberculosis isolates were genotyped by 12 loci mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) and Spoligotyping. Forty-five (72.6%) of the isolates showed unique MIRU-VNTR genotypes, and 13 (21%) of the isolates were grouped into four clusters. Four isolates showed polyclonal MIRU-VNTR genotypes. The MIRU-VNTR Hunter-Gaston discriminatory index reached 0.988. The Spoligotyping analysis revealed 16 M. tuberculosis families, including Latin American-Mediterranean, Harlem, and Beijing. These findings suggest a wide genetic diversity of M. tuberculosis isolates at one outpatient clinic. A detailed molecular epidemiology survey is now warranted, especially following second massive immigration for local Panama Canal expansion activities. PMID:24865686

  5. Tratamiento con caspofungina de endocarditis por Candida tropicalis resistente a fluconazol Treatment with caspofungin of Candida tropicalis endocarditis resistant to fluconazol

    Directory of Open Access Journals (Sweden)

    Marcelo del Castillo

    2004-04-01

    Full Text Available Las endocarditis causadas por hongos, (Candida en particular, requieren tratamiento médico-quirúrgico, siendo la anfotericina B la droga de elección. Caspofungina es una equinocandina con gran actividad sobre Candida y Aspergillus. Se presenta un paciente con una endocarditis por Candida tropicalis resistente a fluconazol tratado con caspofungina bajo un esquema de salvataje, luego de haber presentado efectos adversos por anfotericina B. El paciente tuvo respuesta microbiológica.Fungal endocarditis, in particular due to Candida species, requires medical and surgical treatment and amphotericin B is the drug of choice. Caspofungin is an echinocandin very effective against Candida and Aspergillus. We present a patient with Candida tropicalis endocarditis, fluconazol resistant, treated with caspofungin, on a compassional basis as a result of adverse effects with amphotericin B. The patient had a microbiological response.

  6. Isavuconazole, micafungin, and 8 comparator antifungal agents' susceptibility profiles for common and uncommon opportunistic fungi collected in 2013: temporal analysis of antifungal drug resistance using CLSI species-specific clinical breakpoints and proposed epidemiological cutoff values.

    Science.gov (United States)

    Pfaller, M A; Rhomberg, P R; Messer, S A; Jones, R N; Castanheira, M

    2015-08-01

    The in vitro activities of isavuconazole, micafungin, and 8 comparator antifungal agents were determined for 1613 clinical isolates of fungi (1320 isolates of Candida spp., 155 of Aspergillus spp., 103 of non-Candida yeasts, and 35 non-Aspergillus molds) collected during a global survey conducted in 2013. The vast majority of the isolates of the 21 different species of Candida, with the exception of Candida glabrata (MIC90, 2 μg/mL), Candida krusei (MIC90, 1 μg/mL), and Candida guilliermondii (MIC90, 8 μg/mL), were inhibited by ≤0.25 μg/mL of isavuconazole. C. glabrata and C. krusei were largely inhibited by ≤1 μg/mL of isavuconazole. Resistance to fluconazole was seen in 0.5% of Candida albicans isolates, 11.1% of C. glabrata isolates, 2.5% of Candida parapsilosis isolates, 4.5% of Candida tropicalis isolates, and 20.0% of C. guilliermondii isolates. Resistance to the echinocandins was restricted to C. glabrata (1.3-2.1%) and C. tropicalis (0.9-1.8%). All agents except for the echinocandins were active against 69 Cryptococcus neoformans isolates, and the triazoles, including isavuconazole, were active against the other yeasts. Both the mold active triazoles as well as the echinocandins were active against 155 Aspergillus spp. isolates belonging to 10 species/species complex. In general, there was low resistance levels to the available systemically active antifungal agents in a large, contemporary (2013), global collection of molecularly characterized yeasts and molds. Resistance to azoles and echinocandins was most prominent among isolates of C. glabrata, C. tropicalis, and C. guilliermondii. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Characteristic of Enterococcus faecium clinical isolates with quinupristin/dalfopristin resistance in China.

    Science.gov (United States)

    Wang, Shanshan; Guo, Yinjuan; Lv, Jingnan; Qi, Xiuqin; Li, Dan; Chen, Zengqiang; Zhang, Xueqing; Wang, Liangxing; Yu, Fangyou

    2016-10-21

    Quinupristin/dalfopristin (Q/D) is a valuable alternative antibiotic to vancomycin for the treatment of multi-drug resistant Enterococcus faecium infections. However, resistance to Q/D in E. faecium clinical isolates and nosocomial dissemination of Q/D-resistant E. faecium have been reported in several countries and should be of concern. From January 2012 to December 2015, 911 E. faecium clinical isolates were isolated from various specimens of inpatients at the first Affiliated Hospital of Wenzhou Medical University located in Wenzhou, east China. Of 911 E. faecium clinical isolates, 9 (1.0 %, 9/911) were resistant to Q/D, with the Q/D MIC values of 64 mg/L(1), 32 mg/L(1), 16 mg/L(3), 8 mg/L(1) and 4 mg/L(3) determined by broth microdilution. All Q/D-resistant isolates were susceptible to vancomycin, tigecycline and teicoplanin but resistant to penicillin, ampicillin and erythromycin. vatE was only found in one Q/D-resistant E. faecium isolate while vatD was not detected in any of the isolates tested. 8 of 9 Q/D-resistant E. faecium isolates were found be positive for both ermB and msrC. The combinations of Q/D resistance determinants were ermB-msrC (7 isolates) and ermB-msrC-vatE (one isolate). ST78, ST761, ST94, ST21 and ST323 accounted for 4, 2, 1, 1 and 1 isolate, respectively, among which ST78 was the prevalent ST. Q/D-resistant E. faecium clinical isolates were first described in China. Carriage of vatE, ermB and msrC was responsible for Q/D resistance.

  8. Molecular epidemiology of Mycobacterium tuberculosis clinical isolates in Southwest Ireland.

    LENUS (Irish Health Repository)

    Ojo, Olabisi O

    2010-10-01

    Tuberculosis has had significant effects on Ireland over the past two centuries, causing persistently higher morbidity and mortality than in neighbouring countries until the last decade. This study describes the results of genotyping and drug susceptibility testing of 171 strains of Mycobacterium tuberculosis complex isolated between January 2004 and December 2006 in a region of Ireland centred on the city of Cork. Spoligotype comparisons were made with the SpolDB4 database and clustered 130 strains in 23 groups, forty-one strains showed unique Spoligotyping patterns. The commonest spoligotypes detected were ST0137 (X2) (16.9%), and ST0351 (15.8%) (\\'U\\' clade). The major spoligotype clades were X (26.2%), U (19.3%), T (15.2%), Beijing (5.9%), Haarlem (4.7%), LAM (4.1%), BOVIS (1.75%), with 12.9% unassigned strains. A 24-locus VNTR genotyping produced 15 clusters containing 49 isolates, with high discrimination index (HGDI>0.99). A combination of Spoligotyping and VNTR reduced the number of clustered isolates to 47 in 15 clusters (27.5%). This study identified ST351 as common among Irish nationals, and found a low rate of drug resistance with little evidence of transmission of drug resistant strains. Strain clustering was significantly associated with age under 55 years and Irish nationality. Only strains of Euro-American lineage formed clusters. Molecular typing did not completely coincide with the results of contact investigations.

  9. Antimicrobial susceptibility of Acinetobacter clinical isolates and emerging antibiogram trends for nosocomial infection management

    Directory of Open Access Journals (Sweden)

    Muhammad Sohail

    2016-06-01

    Full Text Available Abstract: Introduction: The drug resistant Acinetobacter strains are important causes of nosocomial infections that are difficult to control and treat. This study aimed to determine the antimicrobial susceptibility patterns of Acinetobacter strains isolated from different clinical specimens obtained from patients belonging to different age groups. METHODS: In total, 716 non-duplicate Acinetobacter isolates were collected from the infected patients admitted to tertiary-care hospitals at Lahore, Pakistan, over a period of 28 months. The Acinetobacter isolates were identified using API 20E, and antimicrobial susceptibility testing was performed and interpreted according to Clinical and Laboratory Standards Institute (CLSI guidelines. RESULTS: The isolation rate of Acinetobacter was high from the respiratory specimens, followed by wound samples. Antibiotic susceptibility analyses of the isolates revealed that the resistance to cefotaxime and ceftazidime was the most common, in 710 (99.2% specimens each, followed by the resistance to gentamicin in 670 (93.6% isolates, and to imipenem in 651 (90.9% isolates. However, almost all isolates were susceptible to tigecycline, colistin, and polymyxin B. CONCLUSIONS: The present study showed the alarming trends of resistance of Acinetobacter strains isolated from clinical specimens to the various classes of antimicrobials. The improvement of microbiological techniques for earlier and more accurate identification of bacteria is necessary for the selection of appropriate treatments.

  10. First Record of Isolation and Characterization of Methicillin Resistant Staphylococcus lugdunensis from Clinical Samples in Iraq

    Science.gov (United States)

    Al-Charrakh, Alaa H.; Obayes, Mohammed H.

    2014-01-01

    This study was conducted to determine the frequency of Staphylococcus lugdunensis in different clinical samples. Out of 690 clinical samples, a total of 178 coagulase negative staphylococci (CoNS) isolates were recovered. CoNS were identified as 10 different species; 22 isolates belonged to Staphylococcus lugdunensis. Two specific genes for S. lugdunensis were used ( tanA gene and fbl gene) to confirm identification. Both of these specific genes were detected in 15 (68.1%) of 22 isolates that were identified phenotypically. The results of oxacillin MIC showed that 7 of the 15 (46.6%) S. lugdunensis isolates were oxacillin resistant. The antibiotic susceptibility testing against 16 antibiotics showed that resistance rates were variable towards these antibiotics. Eight of fifteen S. lugdunensis isolates (53.3%) were β-lactamase producer. Results of molecular detection of mecA gene found that mecA gene was detected in 6 (40%) of 15 S. lugdunensis. All of these 6 isolates (S1, S2, S3, S4, S5, and S6) were resistant to oxacillin. One isolate (S7) was resistant to oxacillin but mecA was not detected in this isolate. This study is a first record of isolation and characterization of methicillin resistant S. lugdunensis (MRSL) from clinical samples in Iraq. PMID:25126573

  11. Study on the percent of frequency of ACME-Arca in clinical isolates ...

    African Journals Online (AJOL)

    ACME is a mobile element of Arginine catabolic in Staphylococcus epidermidis that codes specific virulence factors. The purpose of this study was to examine the specific features and prevalence of ACME-arcA in the isolates of Staphylococcus epidermidis resistant to Methicillin isolated by clinical samples in Isfahan.

  12. In vitro characterization of representative clinical South African Staphylococcus aureus isolates from various clonal lineages

    NARCIS (Netherlands)

    Oosthuysen, W F; Orth, H; Lombard, C. J.; Sinha, B; Wasserman, E

    Data concerning the virulence and pathogenesis of South African strains of Staphylococcus aureus are limited. We investigated host-pathogen interactions of randomly selected clinical S. aureus isolates representing various clones. We characterized the ability of isolates to adhere to fibronectin,

  13. Aspergillus pragensis sp nov discovered during molecular reidentification of clinical isolates belonging to Aspergillus section Candidi

    DEFF Research Database (Denmark)

    Lyskova, Pavlina; Hubka, Vit; Kolarik, Miroslav

    2014-01-01

    The identity of nine clinical isolates recovered from Czech patients and presumptively identified as Aspergillus sp. section Candidi based on colony morphology was revised using sequences of beta-tubulin, calmodulin gene sequence, and internal transcribed spacer rDNA. Six isolates were from suspe...

  14. Complete Genome Sequence of the Campylobacter ureolyticus Clinical Isolate RIGS 9880

    DEFF Research Database (Denmark)

    Miller, William G; Yee, Emma; On, Stephen L W

    2015-01-01

    The emerging pathogen Campylobacter ureolyticus has been isolated from human and animal genital infections, human periodontal disease, domestic and food animals, and from cases of human gastroenteritis. We report the whole-genome sequence of the human clinical isolate RIGS 9880, which is the first...

  15. Anti-microbial resistance of non-clinical E. coli isolates from a ...

    African Journals Online (AJOL)

    The anti-microbial resistance profiles of non-clinical E. coli isolates were studied in an 8 years old commercial layer poultry farm in Imo state, Nigeria currently stocking about 6000 birds of different strains and ages, housed in 4 separate buildings. Isolates were screened against 12 antibiotics using the disc diffusion method.

  16. Adhesion and virulence factor properties of Enterococci isolated from clinical samples in Iran

    Directory of Open Access Journals (Sweden)

    Hossein Samadi Kafil

    2013-01-01

    Full Text Available Introduction: Enterococci rank among leading causes of nosocomial bacteremia, urinary tract infections and community acquired endocarditis. The aim of the present study was to investigate the presence of virulence factors in Enterococci strains isolated from clinical samples in Iranian Educational hospitals. Methodology: Presence of aggregation substance (asa, extracellular surface protein (esp, Enterococcus faecalis antigen A (efaA, adhesin of collagen from E. faecalis (ace, endocarditis and biofilm-associated pilli (ebp as colonization factors and cytolysin (cyl, gelatinase (gel and hyaloronidase (hyl as secretary factors were investigated in isolates. A total of 201 clinical isolates of Enterococci were collected in 2009-2010 from eight educational hospitals. After deoxyribonucleic acid extraction, they were examined for presence of virulence factors by polymerase chain reaction. Results: E. faecalis and Enterococcus faecium were isolated from 56.9% to 43.1%, respectively. Resistance to vancomycin and gentamicin were 33.8% and 83.9% in E. faecium isolates and 16.3% and 88.1% in E. faecalis isolates respectively. Colonization factors were found to be more prevalent in E. faecalis isolates and almost all isolates of E. faecalis had ace, ebp and efaA genes. Esp gene had a higher rate of distribution in Enterococci isolates (75.1% in this study compared with previous studies. One of E. faecalis isolates contained hyl gene, but 38.8% of E. faecium isolates had it. Mutual exclusive were present between hyl and efaA in all E. faecium isolates and 69.7% of E. faecium hyl - positive isolates were esp positive. Conclusion: According to these results, virulence genes were more prevalent in E. faecalis isolates and E. faecalis had more potential pathogenesis for initiating an infection; however because of E. faeciums higher antibiotic resistance, we have been facing higher E. faecium infections in hospitalized patients.

  17. Characterizing clinical isolates of Acanthamoeba castellanii with high resistance to polyhexamethylene biguanide in Taiwan

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    Fu-Chin Huang

    2017-10-01

    Conclusion: Our results confirm the existence of clinical isolates of A. castellanii with high resistance to PHMB in Taiwan and present the alternative drug tolerance of A. castellanii in addition to the transformation of pseudocyst/cyst.

  18. [Study on VNTR diversity of clinical Mycobacterium tuberculosis isolates from Qinghai].

    Science.gov (United States)

    Li, Bin; Liu, Haican; Wang, Zhaofen; Ma, Yongcheng; Su, Xiaodong; Jiang, Mingxia; Wan, Kanglin; Liu, Shou; Zhao, Xiuqin; Qu, Shugen

    2015-10-01

    To investigate the variable number tandem repeats (VNTR) genetic polymorphisms, genotyping and distribution pattern of clinical Mycobacterium (M.) tuberculosis isolates from Qinghai province. The clinical M. tuberculosis strains isolated from the patients with tuberculosis and related background data were collected from Qinghai Provincial Center for Disease Control and Prevention from 2009 to 2012. Genotyping was conducted by using multiple locus VNTR analysis (MLVA). Genomic DNA was extracted and 15 VNTR loci were amplified with PCR and the PCR products were detected with gel electrophoresis. The VNTR diversity and clusters of genotyping were analyzed with BioNumerics (Version 5.0). A total of 251 clinical M. tuberculosis isolates were analyzed with 15 VNTR loci showing that there were great genetic diversity in these isolates. Six of the 15 VNTR loci, showed that the Hunter-Gaston index (HGI) were higher than 0.6, in which the highest resolution was MIRU26. The clusters of genotyping showed that these isolates could be categorized into four gene clusters and 238 genotypes. The four gene clusters accounted for 4.9%, 91.9%, 1.6% and 1.6% of the clinical isolates, respectively. The results showed that there is great variety of VNTR genetic polymorphisms in clinical M. tuberculosis isolates in Qinghai province.

  19. MALDI-TOF mass spectrometry proteomic based identification of clinical bacterial isolates

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    Ashutosh Panda

    2014-01-01

    Full Text Available Background & objectives: Pathogenic bacteria often cause life threatening infections especially in immunocompromised individuals. Therefore, rapid and reliable species identification is essential for a successful treatment and disease management. We evaluated a rapid, proteomic based technique for identification of clinical bacterial isolates by protein profiling using matrix-assisted laser desorption-ionization time - of - flight mass spectrometry (MALDI-TOF MS. Methods: Freshly grown bacterial isolates were selected from culture plates. Ethanol/formic acid extraction procedure was carried out, followed by charging of MALDI target plate with the extract and overlaying with α-cyano-4 hydroxy-cinnamic acid matrix solution. Identification was performed using the MALDI BioTyper 1.1, software for microbial identification (Bruker Daltonik GmbH, Bremen, Germany. Results: A comparative analysis of 82 clinical bacterial isolates using MALDI -TOF MS and conventional techniques was carried out. Amongst the clinical isolates, the accuracy at the species level for clinical isolates was 98.78%. One out of 82 isolates was not in accordance with the conventional assays because MALDI-TOF MS established it as Streptococcus pneumoniae and conventional methods as Streptococcus viridans. Interpretation & conclusions: MALDI - TOF MS was found to be an accurate, rapid, cost-effective and robust system for identification of clinical bacterial isolates. This innovative approach holds promise for earlier therapeutic intervention leading to better patient care.

  20. Genetic Profile Variation in Vaccine Strains and Clinical Isolates of Bordetella pertussis Recovered from Iranian Patients

    OpenAIRE

    Haghighi, Faezeh; Shahcheraghi, Fereshteh; Abbasi, Ebrahim; Eshraghi, Seyed Saeed; Zeraati, Hojjat; Mousavi, Seyed Ali Javad; Asgarian-Omran, Hossein; Douraghi, Masoumeh; Shokri, Fazel

    2014-01-01

    Background Re-emergence of pertussis has been reported in Iran despite a high rate of vaccination coverage. Low efficacy of the vaccine might be due to the genetic divergence between clinical versus vaccine strains. In the current study, the genetic profiles of clinical isolates and vaccine strains of Bordetella pertussis (B. pertussis) were assessed by using Pulsed Field Gel Electrophoresis (PFGE). Methods Following phenotypic and molecular identification of isolates, XbaI-digested genomic D...

  1. Sympathicotomy for Isolated Facial Blushing: A Randomized Clinical Trial

    DEFF Research Database (Denmark)

    Licht, P. B.; Pilegaard, Hans; Ladegaard, L.

    2012-01-01

    Background. Facial blushing is one of the most peculiar of human expressions. The pathophysiology is unclear, and the prevalence is unknown. Thoracoscopic sympathectomy may cure the symptom and is increasingly used in patients with isolated facial blushing. The evidence base for the optimal level...... experienced Horner's syndrome. Compensatory sweating occurred in 93% of patients, gustatory sweating 36%, and dry hands in 66%; 13% of patients regretted the operation despite thorough preoperative selection and information. Conclusions. There were no significant differences in local effects or side effects...

  2. Prevalence of Candida tropicalis and Candida krusei in onychomycosis in João Pessoa, Paraiba, Brazil from 1999 to 2010

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    JULIANA M.M. ARRUA

    2015-09-01

    Full Text Available ABSTRACTOver time, as the etiology of onychomycosis has developed, yeasts from the genus Candida have emerged as important etiological agents. This study aimed to determine the frequency of yeast caused onychomycosis in Joao Pessoa, Paraíba, Brazil from 1999 to 2010. A retrospective study from January 1999 to December 2010 evaluated the results of onychomycosis positive direct mycological exams (DME - for yeast and realized in the Hemato(r Clinical Laboratory. Women were the most affected by onychomycosis which occur preferentially in adults, and the toenails are the favorite yeast targets. The prevalent yeasts were Candida tropicalis and C. krusei.

  3. Antifungal Activity of Bee Venom and Sweet Bee Venom against Clinically Isolated Candida albicans

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    Seung-Bae Lee

    2016-03-01

    Full Text Available Objectives: The purpose of this study was to investigate the antifungal effect of bee venom (BV and sweet bee venom (SBV against Candida albicans (C. albicans clinical isolates. Methods: In this study, BV and SBV were examined for antifungal activities against the Korean Collection for Type Cultures (KCTC strain and 10 clinical isolates of C. albicans. The disk diffusion method was used to measure the antifungal activity and minimum inhibitory concentration (MIC assays were performed by using a broth microdilution method. Also, a killing curve assay was conducted to investigate the kinetics of the anti- fungal action. Results: BV and SBV showed antifungal activity against 10 clinical isolates of C. albicans that were cultured from blood and the vagina by using disk diffusion method. The MIC values obtained for clinical isolates by using the broth microdilution method varied from 62.5 μg/ mL to 125 μg/mL for BV and from 15.63 μg/mL to 62.5 μg/mL for SBV. In the killing-curve assay, SBV behaved as amphotericin B, which was used as positive control, did. The antifungal efficacy of SBV was much higher than that of BV. Conclusion: BV and SBV showed antifungal activity against C. albicans clinical strains that were isolated from blood and the vagina. Especially, SBV might be a candidate for a new antifungal agent against C. albicans clinical isolates.

  4. Influence of different susceptibility testing methods and media on determination of the relevant fluconazole minimum inhibitory concentrations for heavy trailing Candida isolates with low-high phenotype.

    Science.gov (United States)

    Alp, Sehnaz; Sancak, Banu; Hascelik, Gulsen; Arikan, Sevtap

    2010-11-01

    We investigated the incidence of trailing growth with fluconazole in 101 clinical Candida isolates (49 C. albicans and 52 C. tropicalis) and tried to establish the convenient susceptibility testing method and medium for fluconazole minimum inhibitory concentration (MIC) determination. MICs were determined by CLSI M27-A2 broth microdilution (BMD) and Etest methods on RPMI-1640 agar supplemented with 2% glucose (RPG) and on Mueller-Hinton agar supplemented with 2% glucose and 0.5 μg ml(-1) methylene blue (GMB). BMD and Etest MICs were read at 24 and 48 h, and susceptibility categories were compared. All isolates were determined as susceptible with BMD, Etest-RPG and Etest-GMB at 24 h. While all isolates were interpreted as susceptible at 48 h on Etest-RPG and Etest-GMB, one C. albicans isolate was interpreted as susceptible-dose dependent (S-DD) and two C. tropicalis isolates were interpreted as resistant with BMD. On Etest-RPG, trailing growth caused widespread microcolonies within the inhibition zone and resulted in confusion in MIC determination. On Etest-GMB, because of the nearly absence of microcolonies within the zone of inhibition, MICs were evaluated more easily. We conclude that, for the determination of fluconazole MICs of trailing Candida isolates, the Etest method has an advantage over BMD and can be used along with this reference method. Moreover, GMB appears more beneficial than RPG for the fluconazole Etest. © 2009 Blackwell Verlag GmbH.

  5. Serotyping and analysis of produced pigments kinds by Pseudomonas aeruginosa clinical isolates

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    Stanković-Nedeljković Nataša

    2011-01-01

    Full Text Available Background/Aim. Pseudomonas aeruginosa (P. aeruginosa is devided into 20 serotypes on the base of the International Antigenic Typing Scheme. P. aeruginosa serotyping is important because of few reasons but epidemiological is the most important. The aim of the study was serotyping of P. aeruginosa clinical isolates, analysing of single clinical isolates P. aeruginosa present in the particular samples, and analysing of pyocianin and fluorescin production in different isolates of P. aeruginosa. Methods. A total of 223 isolates of P. aeruginosa, isolated in the microbiological laboratory of the Health Center “Aleksinac”, Aleksinac, were examinated. P. aeruginosa isolates were put on the pseudomonas isolation agar, pseudomonas agar base, acetamid agar, asparagin prolin broth, pseudomonas asparagin broth, Bushnnell-Haas agar, cetrimid agar base, King A and King B plates, plates for pyocianin production, plates for fluorescin production and tripticasa soya agar (Himedia. Polyvalent and monovalent serums were used in the agglutination (Biorad. Pigment production was analysed on the bases of growth on the plates for pyocianin and fluorescin production. Results. Serologically, we identificated the serovars as follows: O1, O3, O4, O5, O6, O7, O8, O10, O11 and O12. O1 (38% was the most often serovar, then O11 (19% and O6 (8.6%. A total of 18.6% (42 isolates did not agglutinate with any serum, whereas 21 isolates agglutinated only with polyvalent serum. The majority of P. aeruginosa isolates produced fluorescin, 129 (58.54%, 53 (22.94% produced pyocianin whereas 49 (21.21% isolates produced both pigments. Conclusion. P. aeruginosa was isolated most of the from urine, sputum and other materials. The majority often serovars were O1, O6 and O11. The most of isolates produced fluorescin (58.54%, while 22.94% producted pyocianin and 21.21% both pigments.

  6. Characterization of Burkholderia rhizoxinica and B. endofungorum isolated from clinical specimens.

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    Jay E Gee

    Full Text Available Eight isolates submitted to CDC from 1989 to 2006 from clinical specimens were initially identified as members of the genus Burkholderia based on preliminary cellular fatty acid analysis and/or 16S rRNA gene sequencing. With the recent descriptions of the new species B. rhizoxinica and B. endofungorum, which are considered endosymbiotic bacteria in Rhizopus microsporus fungi, we now identify seven of these clinical isolates as B. rhizoxinica and one as B. endofungorum based on biochemical testing, 16s rRNA, and DNA-DNA hybridization results. We also further characterize these isolates by assessing toxin production and/or by multiple locus sequence typing.

  7. Effects of Endocrine Disruptors Ethinylestradiol and Procloraz on the vocal system of the frog Xenopus tropicalis

    DEFF Research Database (Denmark)

    Brande-Lavridsen, Nanna; Nørum, Ulrik; Korsgaard, Bodil

    2009-01-01

    for studying the effects of endocrine disruptors on sexual differentiation. We exposed tadpoles and metamorphs of the species Xenopus tropicalis to the synthetic estrogen ethinylestradiol and the fungicide prochloraz. Prochloraz masculinized the larynx of female frogs while ethinylestradiol had no effect...

  8. Identification and characterization of Xenopus tropicalis common progenitors of Sertoli and peritubular myoid cell lineages

    Czech Academy of Sciences Publication Activity Database

    Tlapáková, T.; Nguyen, T.M.X.; Vegrichtova, M.; Šídová, Monika; Strnadova, K.; Bláhová, M.; Krylov, V.

    2016-01-01

    Roč. 5, č. 9 (2016), s. 1275-1282 ISSN 2046-6390 R&D Projects: GA AV ČR LK21305; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:86652036 Keywords : Testicular somatic cells * Xenopus tropicalis * Migration potential Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.095, year: 2016

  9. PRIMARY STRUCTURE OF THE CYTOCHROME P450 LANOSTEROL 14A-DEMETHYLASE GENE FROM CANDIDA TROPICALIS

    Science.gov (United States)

    We report the nucleotide sequence of the gene and flanking DNA for the cytochrome P450 lanosterol 14 alpha-demethylase (14DM) from the yeast Candida tropicalis ATCC750. An open reading frame (ORF) of 528 codons encoding a 60.9-kD protein is identified. This ORF includes a charact...

  10. Genome-wide transcriptional response of Silurana (Xenopus tropicalis to infection with the deadly chytrid fungus.

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    Erica Bree Rosenblum

    Full Text Available Emerging infectious diseases are of great concern for both wildlife and humans. Several highly virulent fungal pathogens have recently been discovered in natural populations, highlighting the need for a better understanding of fungal-vertebrate host-pathogen interactions. Because most fungal pathogens are not fatal in the absence of other predisposing conditions, host-pathogen dynamics for deadly fungal pathogens are of particular interest. The chytrid fungus Batrachochytrium dendrobatidis (hereafter Bd infects hundreds of species of frogs in the wild. It is found worldwide and is a significant contributor to the current global amphibian decline. However, the mechanism by which Bd causes death in amphibians, and the response of the host to Bd infection, remain largely unknown. Here we use whole-genome microarrays to monitor the transcriptional responses to Bd infection in the model frog species, Silurana (Xenopus tropicalis, which is susceptible to chytridiomycosis. To elucidate the immune response to Bd and evaluate the physiological effects of chytridiomycosis, we measured gene expression changes in several tissues (liver, skin, spleen following exposure to Bd. We detected a strong transcriptional response for genes involved in physiological processes that can help explain some clinical symptoms of chytridiomycosis at the organismal level. However, we detected surprisingly little evidence of an immune response to Bd exposure, suggesting that this susceptible species may not be mounting efficient innate and adaptive immune responses against Bd. The weak immune response may be partially explained by the thermal conditions of the experiment, which were optimal for Bd growth. However, many immune genes exhibited decreased expression in Bd-exposed frogs compared to control frogs, suggesting a more complex effect of Bd on the immune system than simple temperature-mediated immune suppression. This study generates important baseline data for ongoing

  11. Phenotypic and molecular identification of Sporothrix isolates of clinical origin in Northeast China.

    Science.gov (United States)

    Yu, Xiaohong; Wan, Zhe; Zhang, Zhenying; Li, Fuqiu; Li, Ruoyu; Liu, Xiaoming

    2013-08-01

    Sporotrichosis is the most common deep mycosis in Northeast China which is an area of high epidemicity due to contact with reeds or cornstalks. In this study, we have characterized a total of 74 clinical isolates from fixed cutaneous, lymphocutaneous and disseminated clinical forms and from Heilongjiang, Jilin, and Liaoning provinces, respectively. All isolates (previously as Sporothrix schenckii) were identified as Sporothrix globosa according to their phenotypic characteristics and calmodulin gene sequences analysis. They were subdivided into two sub-clades (S. globosa I and S. globosa II). Most of our isolates (71/74) presented restricted growth at 37 °C, which differed from a previous report. Up to now, S. globosa is the only pathogenic species in Northeast China, no matter what kind of clinical form and which region it is isolated from. Most of our clinical isolates (68/74) were clustered with three Chinese environmental isolates reported in the literature. The new findings of S. globosa isolates on division and thermotolerance at 37 °C described in this study will help us gain a better understanding of S. globosa.

  12. Phenotypic and Genotypic Characterization of Enterotoxigenic Escherichia coli Clinical Isolates from Northern Colombia, South America

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    Julio A. Guerra

    2014-01-01

    Full Text Available Enterotoxigenic Escherichia coli (ETEC are major causes of childhood diarrhea in low and middle income countries including Colombia, South America. To understand the diversity of ETEC strains in the region, clinical isolates obtained from northern Colombia children were evaluated for multiple locus sequencing typing, serotyping, classical and nonclassical virulence genes, and antibiotic susceptibility. Among 40 ETEC clinical isolates evaluated, 21 (52.5% were positive for LT gene, 13 (32.5% for ST gene, and 6 (15% for both ST and LT. The most prevalent colonization surface antigens (CS were CS21 and CFA/I identified in 21 (50% and 13 (32.5% isolates, respectively. The eatA, irp2, and fyuA were the most common nonclassical virulence genes present in more than 60% of the isolates. Ampicillin resistance (80% of the strains was the most frequent phenotype among ETEC strains followed by trimethoprim-sulfamethoxazole resistance (52.5%. Based on multiple locus sequencing typing (MLST, we recognize that 6 clonal groups of ETEC clinical isolates circulate in Colombia. ETEC clinical isolates from children in northern Colombia are highly diverse, yet some isolates circulating in the community belong to well-defined clonal groups that share a unique set of virulence factors, serotypes, and MLST sequence types.

  13. MRI criteria for MS in patients with clinically isolated syndromes

    DEFF Research Database (Denmark)

    Montalban, X.; Tintore, M.; Swanton, J.

    2010-01-01

    In recent years, criteria for the diagnosis of multiple sclerosis (MS) have changed, mainly due to the incorporation of new MRI criteria. While the new criteria are a logical step forward, they are complex and-not surprisingly-a good working knowledge of them is not always evident among neurologi...... false positive diagnoses. New data that are now published were reviewed and discussed and together with a new proposal are integrated in this position paper. Neurology(R) 2010;74:427-434...... isolated syndrome. Within the European multicenter collaborative research network that studies MRI in MS (MAGNIMS), a workshop was held in London in November 2007 to review information that may simplify the existing MS diagnostic criteria, while maintaining a high specificity that is essential to minimize...

  14. Experimental arthritis induced by a clinical Mycoplasma fermentans isolate

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    Giono Silvia

    2002-06-01

    Full Text Available Abstract Background Mycoplasma fermentans has been associated with rheumatoid arthritis. Recently, it was detected in the joints and blood of patients with rheumatoid arthritis, but it is not clear yet how the bacteria enter the body and reach the joints. The purpose of this study was to determine the ability of M. fermentans to induce experimental arthritis in rabbits following inoculation of the bacteria in the trachea and knee joints. Methods P-140 and PG-18 strains were each injected in the knee joints of 14 rabbits in order to evaluate and compare their arthritogenicity. P-140 was also injected in the trachea of 14 rabbits in order to test the ability of the bacteria to reach the joints and induce arthritis. Results M. fermentans produced an acute arthritis in rabbits. Joint swelling appeared first in rabbits injected with P-140, which caused a more severe arthritis than PG-18. Both strains were able to migrate to the uninoculated knee joints and they were detected viable in the joints all along the duration of the experiment. Changes in the synovial tissue were more severe by the end of the experiment and characterized by the infiltration of neutrophils and substitution of adipose tissue by connective tissue. Rabbits intracheally injected with P-140 showed induced arthritis and the bacteria could be isolated from lungs, blood, heart, kidney, spleen, brain and joints. Conclusion M. fermentans induced arthritis regardless of the inoculation route. These findings may help explain why mycoplasmas are commonly isolated from the joints of rheumatic patients.

  15. Characterization of bacteriophages infecting clinical isolates of Pseudomonas aeruginosa stored in a culture collection

    Directory of Open Access Journals (Sweden)

    C.C.S. Zanetti

    2013-08-01

    Full Text Available Some clinical isolates of Pseudomonas aeruginosa stored in our culture collection did not grow or grew poorly and showed lysis on the culture plates when removed from the collection and inoculated on MacConkey agar. One hypothesis was that bacteriophages had infected and killed those clinical isolates. To check the best storage conditions to maintain viable P. aeruginosa for a longer time, clinical isolates were stored at various temperatures and were grown monthly. We investigated the presence of phage in 10 clinical isolates of P. aeruginosa stored in our culture collection. Four strains of P. aeruginosa were infected by phages that were characterized by electron microscopy and isolated to assess their ability to infect. The best condition to maintain the viability of the strains during storage was in water at room temperature. Three Siphoviridae and two Myoviridae phages were visualized and characterized by morphology. We confirmed the presence of bacteriophages infecting clinical isolates, and their ability to infect and lyse alternative hosts. Strain PAO1, however, did not show lysis to any phage. Mucoid and multidrug resistant strains of P. aeruginosa showed lysis to 50% of the phages tested.

  16. Study of antibiotic resistance by efflux in clinical isolates of Pseudomonas aeruginosa.

    Science.gov (United States)

    Abdi-Ali, A; Rahmani-Badi, A; Falsafi, T; Nikname, V

    2007-03-15

    Twenty three multidrug resistant (MDR) strains were selected from 104 clinical isolates of P. aeruginosa and screened for resistance to ceftazidim, ceftriaxone, ciprofloxacin, ofloxacin and ethidium bromide by determining MICs. The MICs of EtBr and antibiotics were also measured in presence of proton conductor, carbonyl cyanide m-chlorophenyl hydrazone (CCCP). The presence of proton gradient-dependent efflux mechanism was assessed using ethidium bromide accumulation assays. Drug accumulation studies for these antibiotics were performed to determine the drug specificity of efflux. PCR was used to identify the mexAB-oprM gene as a major factor in MDR intrinsic resistance of clinical isolates of P. aeruginosa. In absence of CCCP, the MICs of these antimicrobial agents were > or = 4 microg L(-1). CCCP reduced the MICs of them at least in 1 dilution. Ethidium bromide accumulation assays confirmed the presence of proton gradient-dependent efflux mechanism in clinical isolates of P. aeruginosa and results of accumulation assays of drugs demonstrate that, active efflux in this bacterium are due to broadly-specific multidrug efflux system(s). PCR products demonstrate the presence of mexAB-oprM operon in 4 strains from 23 clinical isolates. These results confirmed the presence of proton gradient-dependent efflux mechanism in all of the clinical isolates of P. aeruginosa and demonstrate that, efflux pumps in this bacterium are broadly-specific multidrug efflux systems. In this study we show that MexAB-OprM multidrug efflux system was expressed in only 17% of clinical isolates of P. aeruginosa. These results confirmed the presence of other multidrug efflux pumps in clinical isolates of P. aeruginosa.

  17. Incidence of bovine clinical mastitis in Jammu region and antibiogram of isolated pathogens

    Science.gov (United States)

    Bhat, Adil Majid; Soodan, Jasvinder Singh; Singh, Rajiv; Dhobi, Ishfaq Ahmad; Hussain, Tufail; Dar, Mohammad Yousuf; Mir, Muheet

    2017-01-01

    Aim: This study was conducted to evaluate the incidence of clinical mastitis in bovines of Jammu region, to identify the infectious organisms responsible for it, and the antimicrobial sensitivity of isolated pathogens. Materials and Methods: The study was conducted on cases that were presented to the Medicine Division of Teaching Veterinary Clinical Complex, Faculty of Veterinary Sciences and Animal Husbandry, R.S. Pura, Jammu, Jammu and Kashmir. A total of 260 cases of bovines were presented from June 30, 2012, to July 01, 2013, out of which 30 cases were of clinical mastitis. The diagnosis of clinical mastitis was made on the basis of history and clinical examination of affected animals. Results: Animal and quarter-wise incidence of clinical mastitis were found to be 11.5% and 5.76%, respectively. Of the 23 isolates obtained, Staphylococcus aureus (60.87%) was the most frequently isolated organism, followed by coagulase negative Staphylococci (13.04%), Streptococcus uberis (4.35%), Streptococcus dysgalactiae (8.69%), and Escherichia coli (13.04%). The antimicrobial sensitivity of isolates revealed maximum sensitivity to enrofloxacin, gentamicin, amoxicillin/sulbactam, ceftriaxone/tazobactam, ceftizoxime, ampicillin/sulbactam and least sensitivity for oxytetracycline and penicillin. Conclusion: Staphylococcus spp. is the major causative agent of clinical mastitis in bovines of Jammu region. The causative agents of the clinical mastitis were most sensitive to enrofloxacin and gentamicin. PMID:28919694

  18. Location of brain lesions predicts conversion of clinically isolated syndromes to multiple sclerosis

    NARCIS (Netherlands)

    Giorgio, A.; Battaglini, M.; Rocca, M.A.; De Leucio, A.; Absinta, M.; van Schijndel, R.A.; Rovira, A.; Tintore, M.; Chard, D.; Ciccarelli, O.; Enzinger, C.; Gasperini, C.; Frederiksen, J.; Filippi, M.; Barkhof, F.; De Stefano, N.

    2013-01-01

    Objectives: To assess in a large population of patients with clinically isolated syndrome (CIS) the relevance of brain lesion location and frequency in predicting 1-year conversion to multiple sclerosis (MS). Methods: In thismulticenter, retrospective study, clinical andMRI data at onset and

  19. Effects of early treatment with glatiramer acetate in patients with clinically isolated syndrome

    DEFF Research Database (Denmark)

    Comi, G.; Martinelli, V.; Rodegher, M.

    2013-01-01

    Background: The placebo-controlled phase of the PreCISe study showed that glatiramer acetate delayed onset of clinically definite multiple sclerosis (CDMS) in patients with clinically isolated syndrome and brain lesions on MRI. Objective: To compare the effects of early versus delayed glatiramer ...

  20. Prevalence, virulence factors and antifungal susceptibility of Candida spp. isolated from bloodstream infections in a tertiary care hospital in Brazil.

    Science.gov (United States)

    Canela, Heliara Maria Spina; Cardoso, Bárbara; Vitali, Lucia Helena; Coelho, Harnoldo Colares; Martinez, Roberto; Ferreira, Márcia Eliana da Silva

    2018-01-01

    Candida spp. are responsible for 80% of all systemic fungal infections and are associated with high mortality rates. This study characterised 79 bloodstream isolates of C. albicans, C. glabrata, C. orthopsilosis, C. parapsilosis and C. tropicalis from patients in a Brazilian hospital. The susceptibility to amphotericin B, caspofungin, fluconazole and voriconazole was determined; virulence factor production was assessed based on haemolysin, phospholipase and proteinase activities, and the patients' clinical characteristics were analysed. C. albicans was the predominant species (44%), followed by C. glabrata (19%), C. tropicalis (19%), C. parapsilosis (14%) and C. orthopsilosis (4%). The candidemia incidence was 1.52 per 1000 admissions, and the crude mortality rate was 52%. One C. albicans isolate was resistant to fluconazole and voriconazole. Moreover, 20.2%, 2.5% and 3.8% of the isolates exhibited dose-dependent susceptibility to fluconazole, voriconazole and caspofungin, respectively. In conclusion, although the C. glabrata incidence was higher than that usually described in Brazil, its increase was previously observed in studies conducted worldwide. Furthermore, the azole resistance of the C. albicans isolate could be due to previous exposure to these antifungals. These results highlight the importance of epidemiological studies and will facilitate an improved understanding of candidemia in the studied hospital. © 2017 Blackwell Verlag GmbH.

  1. Simultaneous overexpression of multidrug efflux pumps in Pseudomonas aeruginosa non-cystic fibrosis clinical isolates.

    Science.gov (United States)

    Poonsuk, Kanchana; Tribuddharat, Chanwit; Chuanchuen, Rungtip

    2014-07-01

    The purpose of this study was to examine expression and regulation of 6 multidrug efflux systems, including MexAB-OprM, MexCD-OprJ, MexEF-OprN, MexXY, MexJK, and MexVW, in 13 non-cystic fibrosis (CF) clinical isolates of Pseudomonas aeruginosa. These isolates displayed a high level of resistance to many clinically important antibiotics. Some isolates simultaneously overexpressed up to 4 different Mex systems, as determined by quantitative real-time reverse transcription PCR. None of the isolates overexpressed MexCD-OprJ, and only 1 isolate overproduced MexJK. All the isolates overexpressed MexXY, while overexpression of MexEF-OprN and MexVW was common. DNA sequencing analysis of regulatory genes showed that no clear correlation could be established among (i) the presence of mutations, (ii) the type of mutations, (iii) the expression level of the Mex systems, and (iv) resistance to antibiotic substrates. The results suggest that the concomitant overexpression of some Mex systems may superimpose their antimicrobial drug efflux capabilities, contributing to the multidrug resistance phenotype in the P. aeruginosa non-CF clinical isolates. The existence of uncharacterized regulators for the Mex systems was signified.

  2. In-vitro Activity of Three Brands of Ceftriaxone against different Clinical Isolates

    Directory of Open Access Journals (Sweden)

    B Thapa

    2010-09-01

    Full Text Available INTRODUCTION: Ceftriaxone is an extended spectrum cephalosporin that has been used for decades for combating infections caused by wide array of pathogens and prescription of antibiotic is in favor of specific brands without realizing the potency of the brand. The in-vitro activity of three brands of ceftriaxone and various antibiotics against clinical isolates is studied. METHODS: This comparative study was carried in Kathmandu Medical College Teaching Hospital (KMCTH, Basic Science Complex, Duwakot, Bhaktapur in 2009. Thirteen clinical isolates isolated from the specimens processed in the Microbiology Laboratory at KMCTH were used. Minimum inhibitory concentration (MIC of three brands of ceftriaxone (A, B, and C was determined by agar dilution and antibiotic resistance patterns were deduced by disc diffusion test. RESULTS: MIC for three brands of ceftriaxone ranged from 256 mg/L. The MIC for brands A and C of ceftriaxone were consistent for all isolates while for brand B, MIC was higher by at least two fold suggesting this brand had less in-vitro activity against isolates tested. All isolates were multi-drug resistant. Ceftriaxone resistant isolates (n = 6 were simultaneously resistant to various antibiotics tested. Imipenem and amino glycosides were sensitive to the isolates studied. CONCLUSIONS: Different brands of ceftriaxone are available in Nepal and imprudent use of less potent antibiotics should be controlled to stop the emergence and spread of multi-drug resistant pathogens and to prevent undue economic burden to the patient and the country. Keywords: agar dilution, ceftriaxone brands, multi-drug resistant.

  3. MRI criteria for MS in patients with clinically isolated syndromes

    DEFF Research Database (Denmark)

    Montalban, X.; Tintore, M.; Swanton, J.

    2010-01-01

    In recent years, criteria for the diagnosis of multiple sclerosis (MS) have changed, mainly due to the incorporation of new MRI criteria. While the new criteria are a logical step forward, they are complex and-not surprisingly-a good working knowledge of them is not always evident among...... neurologists and neuroradiologists. In some circumstances, several MRI examinations are needed to achieve an accurate and prompt diagnosis. This provides an incentive for continued efforts to refine the incorporation of MRI-derived information into the diagnostic workup of patients presenting with a clinically...

  4. Isolation and characterization of multidrug-resistant Leclercia species from animal clinical case.

    Science.gov (United States)

    Choudhary, M; Choudhary, B K; Bhoyar, S; Kale, S B; Chaudhari, S P; Bera, B C; Jain, A; Barbuddhe, S B

    2018-01-01

    Leclercia adecarboxylata, a Gram-negative bacillus of family Enterobacteriaceae, is an uncommonly identified pathogen isolated from environmental and clinical specimens. Most of the human infections are polymicrobial and commonly occur in immunocompromised hosts, although nosocomial infections in immunocompetent hosts have been documented. Here, we describe the case of isolation of Leclercia species as polymicrobial infection from bovine suffering from respiratory distress in Chhattisgarh state of India. The isolates were identified by their phenotypes, 16S rDNA sequencing and MALDI-TOF-MS. The isolate was found to be resistant to aminoglycosides and fluoroquinolone antibiotics and intermediate resistant to cephalosporins and evidenced for uncertain clinical relevance and could act as hidden source of public health hazard. Leclercia adecarboxylata is a rarely reported human pathogen. We report here the case from bovine suffering from respiratory distress; the sample yielded Leclercia species as polymicrobial culture. The isolate was found to be multidrug resistant and evidenced for uncertain clinical relevance and could act as hidden source of public health hazard. The limited literature available on this organism is reviewed, and the potential implications of findings are discussed. To the best of our knowledge, this is the first report of isolation and characterization of multidrug-resistant Leclercia species from animal clinical case from India. © 2017 The Society for Applied Microbiology.

  5. Workload and clinical significance of the isolation of zygomycetes in a tertiary general hospital.

    Science.gov (United States)

    Torres-Narbona, M; Guinea, J; Martínez-Alarcón, J; Muñoz, P; Peláez, T; Bouza, E

    2008-05-01

    Several reports of increases in invasive zygomycosis (IZ) at individual institutions across the USA and Europe have contributed to a generalized concept that IZ is an increasing problem and the overestimation of the clinical significance of the isolation of zygomycetes in microbiology departments. We assessed the workload and clinical significance of zygomycetes isolates recovered from clinical samples in our institution over a 19-year period (1988-2006). We retrospectively reviewed the charts of those patients from who isolates of zygomycetes were obtained and calculated the workload of its isolation, the incidence of IZ during this period and the positive predictive value (PPV) of a positive culture. Zygomycetes were recovered from 210 samples (176 patients), i.e., 0.086/1,000 clinical samples processed and 6.3/1,000 samples submitted for fungal isolation. Zygomycetes represented 0.6% of the total fungi recovered. The mean incidence of the disease was 1.2 cases/100,000 admissions (range 0-20). Only 16 of the samples which grew zygomycetes (7.6%) were from infected patients. The workload generated by zygomycetes in our institution and the PPV for IZ of their isolation in our laboratory were very low and the disease was not found to have significantly increased in recent years in our institution. Data from specific institutions cannot be generalized.

  6. Isolation, speciation, and antibiogram of clinically relevant non-diphtherial Corynebacteria (Diphtheroids

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    B S Reddy

    2012-01-01

    Full Text Available Purpose: Coryneform or the non-diphtherial Corynebacterium species largely remains a neglected group with the traditional consideration of these organisms as contaminants. This concept, however, is slowly changing in the light of recent observations. This study has been done to find out the species distribution and antibiogram of various members of the clinically relevant Coryneform group, isolated from various clinical materials. Materials and Methods: One hundred and fourteen non-duplicate isolates of diphtheroids from various clinical isolates were selected for the study. The isolates were identified to the species level by using a battery of tests; and antimicrobial susceptibility was tested by using a combination of Clinical and Laboratory Standards Institute (CLSI and the British Society for Antimicrobial Chemotherapy (BSAC guidelines, in the absence of definitive CLSI guidelines. Results: Corynebacterium amycolatum was the predominant species (35.9% in our series followed by the CDC Group G organisms (15.7%. Each of the remaining 19 species comprised of less than 10% of the isolates. More than half the total isolates were resistant to the penicillins, erythromycin, and clindamycin; while excellent activity (all the strains being susceptible was shown by vancomycin, linezolid, and tigecycline. Chloramphenicol and tetracycline also had good activity in inhibiting more than 80% of the isolates. Multiply drug resistance was exhibited by all the species. Conclusion: This study was an attempt to establish the clinical significance of coryneform organisms. The high level of resistance shown by this group to some of the common antibacterial agents highlights the importance of processing these isolates in select conditions to guide the clinicians towards an appropriate therapy.

  7. Nontuberculous Mycobacteria Isolation from Clinical and Environmental Samples in Iran: Twenty Years of Surveillance

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    Ali Akbar Velayati

    2015-01-01

    Full Text Available Nontuberculous mycobacteria (NTM are opportunistic pathogens that are widely distributed in the environment. There is a lack of data on species distribution of these organisms from Iran. This study consists of a review of NTM articles published in Iran between the years 1992 and 2014. In this review, 20 articles and 14 case reports were identified. Among the 20 articles, 13 (65% studies focused on NTM isolates from clinical specimens, 6 (30% studies examined NTM isolates from environmental samples, and one (5% article included both clinical and environmental isolates. M. fortuitum (229/997; 23% was recorded as the most prevalent and rapid growing mycobacteria (RGM species in both clinical (28% and environmental (19% isolated samples (P < 0.05. Among slow growing mycobacteria (SGM, M. simiae (103/494; 21% demonstrated a higher frequency in clinical samples whereas in environmental samples it was M. flavescens (44/503; 9%. These data represent information from 14 provinces out of 31 provinces of Iran. No information is available in current published data on clinical or environmental NTM from the remaining 17 provinces in Iran. These results emphasize the potential importance of NTM as well as the underestimation of NTM frequency in Iran. NTM is an important clinical problem associated with significant morbidity and mortality in Iran. Continued research is needed from both clinical and environmental sources to help clinicians and researchers better understand and address NTM treatment and prevention.

  8. Isolated persistent left superior vena cava: A case report and its clinical implications

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    Samarjit Bisoyi

    2017-01-01

    Full Text Available The venous anomaly of a persistent left superior vena cava (PLSVC affects 0.3%-0.5% of the general population. PLSVC with absent right superior vena cava, also termed as "isolated PLSVC," is an extremely rare venous anomaly. Almost half of the patients with isolated PLSVC have cardiac anomalies in the form of atrial septal defect, endocardial cushion defects, or tetralogy of Fallot. Isolated PLSVC is usually innocuous. Its discovery, however, has important clinical implications. It can pose clinical difficulties with central venous access, cardiothoracic surgeries, and pacemaker implantation. When it drains to the left atrium, it may create a right to left shunt. In this case report, we present the incidental finding of isolated PLSVC in a patient who underwent aortic valve replacement. Awareness about this condition and its variations is important to avoid complications.

  9. Association of biofilm production with colonization among clinical isolates of Acinetobacter baumannii.

    Science.gov (United States)

    Ryu, Seong Yeol; Baek, Won-Ki; Kim, Hyun Ah

    2017-03-01

    The pathogen Acinetobacter baumannii is increasingly causing healthcare-associated infections worldwide, particularly in intensive care units. Biofilm formation, a factor contributing to the virulence of A. baumannii , is associated with long-term persistence in hospital environments. The present study investigates the clinical impact of biofilm production on colonization and acquisition after patient admission. Forty-nine A. baumannii isolates were obtained between August and November 2013 from Keimyung University Dongsan Medical Center, Daegu, Korea. All isolates were obtained from sputum samples of new patients infected or colonized by A. baumannii . The microtiter plate assay was used to determine biofilm formation. Twenty-four A. baumannii isolates (48%) demonstrated enhanced biofilm formation capacity than that of the standard A. baumannii strain (ATCC 19606). All isolates were resistant to carbapenem, 38 isolates (77%) were collected from patients in an intensive care unit, and 47 isolates (95%) were from patients who had been exposed to antibiotics in the previous month. The median duration of colonization was longer for biofilm-producing isolates than that of the biofilm non-biofilm producing isolates (18 days vs. 12 days, p < 0.05). Simultaneous colonization with other bacteria was more common for biofilm-producing isolates than that for the non-biofilm producing isolates. The most prevalent co-colonizing bacteria was Staphylococcus aureus . Biofilm-producing isolates seem to colonize the respiratory tract for longer durations than the non-biofilm producing isolates. During colonization, biofilm producers promote co-colonization by other bacteria, particularly S. aureus . Additional research is required to determine possible links between biofilm formation and nosocomial infection.

  10. Prevalence of beta-lactams resistance among Escherichia coli clinical isolates from a hospital in Algiers.

    Science.gov (United States)

    Messai, Y; Benhassine, T; Naim, M; Paul, G; Bakour, R

    2006-06-01

    A high prevalence of beta-lactams resistance among Enterobacteriaceae have been reported worldwide; however, there are not sufficient data on this issue in Algeria. beta-Lactams susceptibility of 203 Escherichia coli clinical isolates was determined by agar diffusion method, and production of extended-spectrum beta-lactamases (ESBL) was screened by double-disk synergy test. This analysis showed five well-defined phenotypes: 1) 62 isolates (30.5%) were susceptible to all beta-lactams; 2) 135 isolates (66.5%) presented a broad-spectrum beta-lactamases phenotype (BSBL); 3) three isolates (1.5%) were defined as producing ESBLs; 4) two isolates (1%) were AmpC cephalosporinase producers; and 5) one isolate (0.5%) presented a phenotype of cell-decreased permeability to beta-lactams. Isoelectric focusing revealed beta-lactamases with isolectric points of 5.4 or 7.6 for isolates with BSBL phenotype; approximately 9.0 for two ESBL isolates; 5.4, 7.6 and approximately 9.0 for the remaining ESBL isolate; and 5.4 and approximately 9.0 for the AmpC isolates. The cefotaxime hydrolysis corresponds to the basic bands with an isoelectric point of approximately 9.0. Conjugation assay showed transfer of penicillinase and AmpC resistance phenotypes and their corresponding beta-lactamases to recipient E. coli BM21 in association with plasmids of 71.4 kb for the AmpC isolates and from 40-56 kb for penicillinase isolates. This result showed that the AmpC phenotype is plasmid mediated. ESBL isolates were found not to transfer their resistance through conjugation experiment. Polymerase chain reaction (PCR) experiments using primers specific to blaTEM, blaAmpC and blaCTX-M genes showed specific amplification with blaCTX-M primer for two ESBL isolates; blaTEM and blaCTX-M for the remaining ESBL isolate; and blaTEM and blaAmpC for the AmpC isolates and their corresponding transconjugants. The study showed a high rate of isolates producing penicillinase, and low frequencies of AmpC and ESBL

  11. Emergence of colistin-resistant Escherichia coli clinical isolates harboring mcr-1 in Vietnam

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    Tatsuya Tada

    2017-10-01

    Full Text Available The mcr-1 was first detected on a plasmid in colistin-resistant Escherichia coli from livestock and patients in China. We described here the emergence of colistin-resistant E. coli clinical isolates harboring mcr-1 on the chromosomes in Vietnam. To our knowledge, this is the first report of hospital-acquired E. coli isolates harboring mcr-1 in a medical setting in Vietnam.

  12. Emergence of colistin-resistant Escherichia coli clinical isolates harboring mcr-1 in Vietnam.

    Science.gov (United States)

    Tada, Tatsuya; Nhung, Pham Hong; Shimada, Kayo; Tsuchiya, Mitsuhiro; Phuong, Doan Mai; Anh, Nguyen Quoc; Ohmagari, Norio; Kirikae, Teruo

    2017-10-01

    The mcr-1 was first detected on a plasmid in colistin-resistant Escherichia coli from livestock and patients in China. We described here the emergence of colistin-resistant E. coli clinical isolates harboring mcr-1 on the chromosomes in Vietnam. To our knowledge, this is the first report of hospital-acquired E. coli isolates harboring mcr-1 in a medical setting in Vietnam. Copyright © 2017. Published by Elsevier Ltd.

  13. Production of Cellulases, Xylanase, Pectinase, alpha-amylase and Protease Enzymes Cocktail by Bacillus spp. and Their Mixed Cultures with Candida tropicalis and Rhodotorula glutinis under Solid State Fermentation

    International Nuclear Information System (INIS)

    El-Batal, A.I.; Abo-State, M.A.

    2006-01-01

    A group of twelve locally isolated Bacillus species, B.megaterium (MAI and MA II), B.licheniformis (MLI and ML II); B. circulans, B. stearothermophilis, B.cereus, B.sphaericus, B. pumilus, B. laterosporus, B. coagulans and B. pantothenticus, were examined for the production of cellulases, xylanase, pectinase, alpha-amylase and protease enzymes cocktail on wheat bran under solid state fermentation (SSF). All species were found to be potent hydrolyzing enzymes producers and the superior producing species were B. megaterium MAI and B. licheniformis. On the other hand, both of them still produced highest enzyme titres when mixed with Candida tropicalis or Rhodotorula glutinis, yeast strains. The two superior bacterial strains produced the highest enzymatic activities when coculturing with C. tropicalis compared with coculturing with R. glutinis only or with both C. tropicalis and R. glutinis in combination. The inferior activities of cocultures (B. megaterinm MAI and R. glutinis) were enhanced in carboxymethyl cellulase (CMCase), filter paper cellulase (FPase), avecilase, xylanase, pectinase, -amylase and protease by gamma irradiation at dose 1.0 kGy with percent increase 8 %, 20 %, 10 %, 4 %, 31 %, 22 % and 34 %, respectively as compared with un-irradiated cocultures

  14. Physicochemical properties of elastase isolated from clinical Pseudomonas Aeruginosa

    International Nuclear Information System (INIS)

    Elbazza, Z.E.; Moroz, A.F.

    1989-01-01

    Purified elastase was obtained from clinical Pseudomonas Aeruginosa (P.A.-283). The enzyme showed not only elasto lytic activity, but also a broad proteolytic activity against various proteins. The activity of the enzyme on collagen and gelatin was also observed. The optimum pH for elastase was 7.8 to 8.0 for both the proteolytic and elasto lytic activities. The elastase was stable in a pH range from 6.6 to 9.0. Optimum temperature for proteolytic and elasto lytic activities was 40 and inhibition of elastase occurs at 80 . The D 1 0 value of the P.A-283 was found to be 0.11 kGy. Increasing the dose level value of gamma-irradiation decrease the proteolytic activity in the culture filtrate reaching only 16% at the dose level 0.5 kGy. Chelating agents and some metal ions inhibited both proteolytic and elasto lytic activities. Selective inhibition of elasto lytic activity was observed in high concentrations of sodium and ammonium salts without concurrent decrease in the proteolytic activity of the enzyme.4 fig., 3 tab

  15. Staphylococcus aureus Clinical Isolates: Antibiotic Susceptibility, Molecular Characteristics, and Ability to Form Biofilm

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    N. Indrawattana

    2013-01-01

    Full Text Available Periodic monitoring of Staphylococcus aureus characteristics in a locality is imperative as their drug-resistant variants cause treatment problem. In this study, antibiograms, prevalence of toxin genes (sea-see, seg-ser, seu, tsst-1, eta, etb, and etd, PFGE types, accessory gene regulator (agr groups, and ability to form biofilm of 92 S. aureus Thailand clinical isolates were investigated. They were classified into 10 drug groups: groups 1–7 (56 isolates were methicillin resistant (MRSA and 8–10 (36 isolates were methicillin sensitive (MSSA. One isolate did not have any toxin gene, 4 isolates carried one toxin gene (seq, and 87 isolates had two or more toxin genes. No isolate had see, etb, or tsst-1; six isolates had eta or etd. Combined seg-sei-sem-sen-seo of the highly prevalent egc locus was 26.1%. The seb, sec, sel, seu, and eta associated significantly with MSSA; sek was more in MRSA. The sek-seq association was 52.17% while combined sed-sej was not found. Twenty-three PFGE types were revealed, no association of toxin genes with PFGE types. All four agr groups were present; agr group 1 was predominant (58.70% but agr group 2 strains carried more toxin genes and were more frequent toxin producers. Biofilm formation was found in 72.83% of the isolates but there was no association with antibiograms. This study provides insight information on molecular and phenotypic markers of Thailand S. aureus clinical isolates which should be useful for future active surveillance that aimed to control a spread of existing antimicrobial resistant bacteria and early recognition of a newly emerged variant.

  16. First insight into the genotypic diversity of clinical Mycobacterium tuberculosis isolates from Gansu Province, China.

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    Jie Liu

    Full Text Available BACKGROUND: Investigations of Mycobacterium tuberculosis genetic diversity in China have indicated a significant regional distribution. The aim of this study was to characterize the genotypes of clinical M. tuberculosis isolates obtained from Gansu, which has a special geographic location in China. METHODOLOGY/PRINCIPAL FINDINGS: A total of 467 clinical M. tuberculosis strains isolated in Gansu Province were genotyped by 15-locus mycobacterial interspersed repetitive units-variable number tandem repeats (MIRU-VNTR and spoligotyping. The results showed that 445 isolates belonged to six known spoligotype lineages, whereas 22 isolates were unknown. The Beijing genotype was the most prevalent (87.58%, n = 409, while the shared type 1 was the dominant genotype (80.94%, n = 378. The second most common lineage was the T lineage, with 25 isolates (5.35%, followed by the H lineage with 5 isolates (1.07%, the MANU family (0.64%, 3 isolates, the U family (0.43%, 2 isolates and the CAS lineage with 1 isolate (0.21%. By using the VNTR15China method, we observed 15 groups and 228 genotypes among the 467 isolates. We found no association between the five larger groups (including the Beijing genotype and sex, age, or treatment status, and there was no noticeable difference in the group analysis in different areas. In the present study, seven of the 15 MIRU-VNTR loci were highly or moderately discriminative according to their Hunter-Gaston discriminatory index. CONCLUSIONS/SIGNIFICANCE: The Beijing genotype is the predominant genotype in Gansu province. We confirm that VNTR15China is suitable for typing Beijing strains in China and that it has a better discriminatory power than spoligotyping. Therefore, the use of both methods is the most suitable for genotyping analysis of M. tuberculosis.

  17. In vitro differential activity of phospholipases and acid proteinases of clinical isolates of Candida Atividade diferencial in vitro de fosfolipases e proteinases ácidas de isolados clínicos de Candida

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    Aurean D'Eça Júnior

    2011-06-01

    Full Text Available INTRODUCTION: Candida yeasts are commensals; however, if the balance of normal flora is disrupted or the immune defenses are compromised, Candida species can cause disease manifestations. Several attributes contribute to the virulence and pathogenicity of Candida, including the production of extracellular hydrolytic enzymes, particularly phospholipase and proteinase. This study aimed to investigate the in vitro activity of phospholipases and acid proteinases in clinical isolates of Candida spp. METHODS: Eighty-two isolates from hospitalized patients collected from various sites of origin were analyzed. Phospholipase production was performed in egg yolk medium and the production of proteinase was verified in a medium containing bovine serum albumin. The study was performed in triplicate. RESULTS: Fifty-six (68.3% of isolates tested were phospholipase positive and 16 (44.4% were positive for proteinase activity. C. tropicalis was the species with the highest number of positive isolates for phospholipase (91.7%. Statistically significant differences were observed in relation to production of phospholipases among species (pINTRODUÇÃO: Candida são leveduras comensais, porém, se o equilíbrio da flora normal for interrompido ou as defesas imunitárias estiverem comprometidas, espécies de Candida podem causar manifestações de doença. Vários atributos contribuem na virulência e patogenicidade de Candida, inclusive a produção de enzimas extracelulares hidrolíticas, especialmente fosfolipases e proteinases. O objetivo deste estudo foi verificar a atividade in vitro de fosfolipases e proteinases ácidas em isolados clínicos de Candida spp. MÉTODOS: Oitenta e dois isolados provenientes de pacientes hospitalizados coletados a partir de sítios de origem diversos foram analisados. A produção de fosfolipase foi verificada em meio egg yolk e a de proteinase em meio contendo soro albumina bovina. O estudo foi feito em triplicata. RESULTADOS

  18. Amdinocillin (Mecillinam) Resistance Mutations in Clinical Isolates and Laboratory-Selected Mutants of Escherichia coli

    Science.gov (United States)

    Thulin, Elisabeth; Sundqvist, Martin

    2015-01-01

    Amdinocillin (mecillinam) is a β-lactam antibiotic that is used mainly for the treatment of uncomplicated urinary tract infections. The objectives of this study were to identify mutations that confer amdinocillin resistance on laboratory-isolated mutants and clinical isolates of Escherichia coli and to determine why amdinocillin resistance remains rare clinically even though resistance is easily selected in the laboratory. Under laboratory selection, frequencies of mutation to amdinocillin resistance varied from 8 × 10−8 to 2 × 10−5 per cell, depending on the concentration of amdinocillin used during selection. Several genes have been demonstrated to give amdinocillin resistance, but here eight novel genes previously unknown to be involved in amdinocillin resistance were identified. These genes encode functions involved in the respiratory chain, the ribosome, cysteine biosynthesis, tRNA synthesis, and pyrophosphate metabolism. The clinical isolates exhibited significantly greater fitness than the laboratory-isolated mutants and a different mutation spectrum. The cysB gene was mutated (inactivated) in all of the clinical isolates, in contrast to the laboratory-isolated mutants, where mainly other types of more costly mutations were found. Our results suggest that the frequency of mutation to amdinocillin resistance is high because of the large mutational target (at least 38 genes). However, the majority of these resistant mutants have a low growth rate, reducing the probability that they are stably maintained in the bladder. Inactivation of the cysB gene and a resulting loss of cysteine biosynthesis are the major mechanism of amdinocillin resistance in clinical isolates of E. coli. PMID:25583718

  19. Differentiation of clinical Mycobacterium tuberculosis complex isolates by their GyrB polymorphism

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    Abass N

    2010-01-01

    Full Text Available Purpose: To evaluate the reliability of the gyrB PCR-RFLP technique in differentiating clinical Mycobacterium tuberculosis complex isolates. Materials and Methods: A primer pair MTUB-f and MTUB-r for M. tuberculosis complex (MTBC was used to differentiate 79 mycobacterial isolates by specific amplification of the 1,020-bp fragment of the gyrB gene (gyrB-PCR1. The MTBC isolates were further differentiated using a set of specific primers MTUB-756-Gf and MTUB-1450-Cr that allowed selective amplification of the gyrB fragment specific for M. tuberculosis (gyrB-PCR2. The DNA polymorphisms in the 1,020-bp gyrB fragment for 7 M. tuberculosis strains confirmed by PCR as well as 2 reference strains; M. tuberculosis H37Rv and M. bovis BCG were analyzed with the restriction enzyme Rsa1. Results: Seventy-seven (97.5% isolates were positive for gyrB-PCR1 and thus identified as members of M. tuberculosis complex (MTBC and two (2.6% isolates were negative and identified as Mycobacteria other than tuberculosis (MOTT. All the M. tuberculosis isolates showed the typical M. tuberculosis specific Rsa1 RFLP patterns (100, 360, 560-bp while 360 and 480-bp fragments were generated from M. bovis BCG. Conclusion: The gyrB PCR-RFLP using the endonuclease Rsa1 can be used to differentiate M. tuberculosis from M. bovis in clinical isolates.

  20. Glucose & sodium chloride induced biofilm production & ica operon in clinical isolates of staphylococci

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    Astha Agarwal

    2013-01-01

    Full Text Available Background & objectives: All colonizing and invasive staphylococcal isolates may not produce biofilm but may turn biofilm producers in certain situations due to change in environmental factors. This study was done to test the hypothesis that non biofilm producing clinical staphylococci isolates turn biofilm producers in presence of sodium chloride (isotonic and high concentration of glucose, irrespective of presence or absence of ica operon. Methods: Clinical isolates of 100 invasive, 50 colonizing and 50 commensal staphylococci were tested for biofilm production by microtiter plate method in different culture media (trypticase soy broth alone or supplemented with 0.9% NaCl/ 5 or 10% glucose. All isolates were tested for the presence of ica ADBC genes by PCR. Results: Biofilm production significantly increased in the presence of glucose and saline, most, when both glucose and saline were used together. All the ica positive staphylococcal isolates and some ica negative isolates turned biofilm producer in at least one of the tested culture conditions. Those remained biofilm negative in different culture conditions were all ica negative. Interpretation & conclusions: The present results showed that the use of glucose or NaCl or combination of both enhanced biofilm producing capacity of staphylococcal isolates irrespective of presence or absence of ica operon.

  1. Biochemical and Molecular Analysis of Staphylococcus aureus Clinical Isolates from Hospitalized Patients

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    Amit Karmakar

    2016-01-01

    Full Text Available Staphylococcus aureus is opportunistic human as well as animal pathogen that causes a variety of diseases. A total of 100 Staphylococcus aureus isolates were obtained from clinical samples derived from hospitalized patients. The presumptive Staphylococcus aureus clinical isolates were identified phenotypically by different biochemical tests. Molecular identification was done by PCR using species specific 16S rRNA primer pairs and finally 100 isolates were found to be positive as Staphylococcus aureus. Screened isolates were further analyzed by several microbiological diagnostics tests including gelatin hydrolysis, protease, and lipase tests. It was found that 78%, 81%, and 51% isolates were positive for gelatin hydrolysis, protease, and lipase activities, respectively. Antibiogram analysis of isolated Staphylococcus aureus strains with respect to different antimicrobial agents revealed resistance pattern ranging from 57 to 96%. Our study also shows 70% strains to be MRSA, 54.3% as VRSA, and 54.3% as both MRSA and VRSA. All the identified isolates were subjected to detection of mecA, nuc, and hlb genes and 70%, 84%, and 40% were found to harbour mecA, nuc, and hlb genes, respectively. The current investigation is highly important and informative for the high level multidrug resistant Staphylococcus aureus infections inclusive also of methicillin and vancomycin.

  2. Increased parasite surface antigen-2 expression in clinical isolates of Leishmania donovani augments antimony resistance.

    Science.gov (United States)

    Bhandari, Vasundhra; Kumar, Dhiraj; Verma, Sandeep; Srividya, Gurumurthy; Negi, Narendra Singh; Singh, Ruchi; Salotra, Poonam

    2013-11-01

    Resistance to sodium antimony gluconate (SAG) is a major cause of therapeutic failure in a large proportion of visceral leishmaniasis (VL) cases. Determinants of SAG resistance have been widely studied; however, the mechanism operating in clinical isolates is poorly understood. In the present study, expression of parasite surface antigen-2 (PSA-2) gene was studied in clinical isolates of Leishmania donovani comprising of antimony resistant (n=10) and sensitive (n=4) parasites. The expression of PSA-2 gene was found to be consistently high in SAG resistant clinical isolates (≥1.5-fold) at both transcript and protein level. Further, over-expression of PSA-2 in L. donovani isolates (LdPSA-2(++)) resulted in conversion of SAG sensitive phenotype to resistant. The LdPSA-2(++) parasites showed significantly decreased susceptibility towards SAG (>12-fold), amphotericin B (>4-fold) and miltefosine (>2.5-fold). Marked decrease in antimony accumulation and enhanced tolerance towards complement mediated lysis was evident in LdPSA-2(++) parasites. The study established the role of PSA-2 gene in SAG resistance and its potential as a biomarker to distinguish resistant and sensitive clinical isolates of L. donovani. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Phenotypic and genotypic evaluation of 18 Nocardia isolates from human clinical samples in Mexico.

    Science.gov (United States)

    Sánchez-Herrera, K; Sandoval, H; Couble, A; Mouniee, D; Ramírez-Durán, N; Uzcategui de Morillo, M; Serrano, J A; Bergeron, E; Boiron, P; Rodríguez-Nava, V

    2012-03-01

    Mexico has the largest number of clinical cases of actinomycetoma in North and South America. Species originally identified by less specific methods have been recently reclassified as other known species or as new species. To assess, by 16S rRNA gene sequencing and phenotypic methods, the species distribution of 18 human clinical isolates originally identified as N. brasiliensis, some of them isolated between 1947 and 1959 in Mexico City. Clinical isolates came from the Hospital General, "Dr. Manuel Gea Gonzalez", and Instituto Nacional de Diagnóstico y Referencia Epidemiológica (INDRE) in Mexico, D.F. The strains used in this study included 15 clinical strains isolated between 1947 and 1959 that were originally identified as N. brasiliensis and three more strains obtained in 2007 identified as Nocardia spp. The isolates were identified genotypically by sequencing the 16S rRNA gene, and their phenotypic profiles were obtained with the API Coryne(®) system. Antibiotic susceptibility patterns were tested according to the protocol of the Comité de l'antibiogramme de la Société française de microbiologie[4]. According to 16S rRNA gene, sequencing were identified among 18 human clinical isolates as Nocardia farcinica (n=11) and Nocardia brasiliensis (n=7). A high number of the strains were susceptible to the majority of the antibiotics tested. The phenotypic profiles of the strains were quite uniform for N. farcinica and some variability was observed for N. brasiliensis strains. N. farcinica was the most prevalent species identified. Modern methodologies should be applied in clinical laboratories to accurately identify etiological agents. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  4. Study the Efficacy of Antimicrobial Activities of Eight Clinically Applied Disinfectants against Clinical Isolated of Enterococci and Pseudomonas aeruginosa

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    Morteza Zareniya, Somayeh Hallaj-Nezhadi, Farideh Dinmohamadi, Fakhri Haghi, Maryam Hassan

    2017-06-01

    Full Text Available Background: Hospital-acquired infections are among the most significant reasons of human mortality world-wide which can be controlled by efficient application of suitable disinfectant for hospital setting. The main goal of the present study was to determine the efficacy of eight routinely used hospital disinfectants against clinical isolates. Methods: In our descriptive study, in the first step the antibiogram assay of 99 clinical isolates enterococci and Pseudomonas aeruginosa were determined. Then, minimum inhibitory concentration and minimum bactericidal concentration of isolates against Povidone Iodine 10%, Ethanol 70%, Savlon 3.2%, Deconex51Gastro, Procept Floor, Septo med, Surfanious and Gigasept AF were evaluated. Furthermore, the efficacy of disinfectants was reevaluated in presence of 5% (w/v Bovine Serum Albumin. Results: The results showed that Septo med and Surfanious are the most and less potent disinfectants against clinical isolates, respectively. It is also resulted that Povidone Iodine is the most effective choice among the conventional disinfectants in this study. Clearly, addition of 5% organic substances reduced the efficacy of selected disinfectants significantly. Conclusion: Novel quaternary ammonium compounds are the most applicable choice for disinfection of hospital surfaces and instruments in this study.

  5. Hemolytic activity of Trichomonas gallinae isolates does not correspond with clinical virulence.

    Science.gov (United States)

    Gerhold, Richard W; Yabsley, Michael J; Fischer, John R

    2009-03-23

    The hemolytic activity of 22 Trichomonas gallinae isolates was investigated using an 18h erythrocyte hemolysis assay which has been shown to correlate with the clinical virulence of T. vaginalis. Absorbance of the assay supernatants was measured at 540nm and expressed as percentage of complete hemolysis. Mean hemolytic activity of the T. gallinae isolates ranged from 3.5% to 53.4% and did not correspond with clinical virulence. The results of this investigation suggest hemolytic activity is not a useful in vitro virulence assay for T. gallinae.

  6. Antimicrobial activity of solithromycin against clinical isolates of Legionella pneumophila serogroup 1.

    Science.gov (United States)

    Mallegol, Julia; Fernandes, Prabhavathi; Melano, Roberto G; Guyard, Cyril

    2014-01-01

    The activity of solithromycin was evaluated against clinical Legionella pneumophila serogroup 1 (Lp1) isolates (n = 196) collected in Ontario, Canada, from 1980 to 2011. Its in vitro activity was compared to that of azithromycin (AZM) using the broth microdilution method. Solithromycin had a MIC50 of ≤0.015 μg/ml and a MIC90 of 0.031 μg/ml, making its activity at least 8-fold to 32-fold higher than that of AZM (MIC50 and MIC90, 0.125 μg/ml and 1 μg/ml, respectively). Ninety-nine percent of the isolates had MICs for solithromycin ranging from ≤0.015 μg/ml to 0.031 μg/ml, whereas 83.6% of the isolates showed MICs for AZM ranging from 0.062 μg/ml to 0.25 μg/ml. Interestingly, 96.7% (30 out of 31 clinical isolates) identified with higher AZM MICs (0.5 μg/ml to 2 μg/ml) belonged to the clinically prevalent sequence type 1. To investigate the intracellular activity of solithromycin, in vitro invasion assays were also performed against a subset of representative Lp1 isolates internalized within human lung epithelial cells. Solithromycin and AZM both inhibited growth of all intracellular Lp1 isolates at 1× or 8× MICs, displaying bacteriostatic effects, as would be expected with protein synthesis inhibitor rather than bactericidal activity. Solithromycin demonstrated the highest in vitro and intracellular potency against all Lp1 isolates compared to AZM. Given the rapid spread of resistance mechanisms among respiratory pathogens and the reported treatment failures in legionellosis, the development of this new fluoroketolide, already in phase 3 oral clinical studies, constitutes a promising alternative option for the treatment of legionellosis.

  7. Antimicrobial resistance in clinical Escherichia coli isolated from companion animals in Australia.

    Science.gov (United States)

    Saputra, Sugiyono; Jordan, David; Mitchell, Tahlia; Wong, Hui San; Abraham, Rebecca J; Kidsley, Amanda; Turnidge, John; Trott, Darren J; Abraham, Sam

    2017-11-01

    Multidrug-resistant (MDR) Escherichia coli have become a major public health concern to both humans and animal health. While the frequency of antimicrobial resistance (AMR) in clinical E. coli is monitored regularly in human medicine, current frequency of AMR in companion animals remains unknown in Australia. In this study we conducted antimicrobial susceptibility testing (AST) and where possible, determined potential risk factors for MDR infection among 883 clinical Escherichia coli isolated from dogs (n=514), cats (n=341) and horses (n=28). AST was undertaken for 15 antimicrobial agents according to the Clinical Laboratory Standards Institute (CLSI) guidelines and interpreted using epidemiological cut-off values (ECOFFs) as well as CLSI veterinary and human clinical breakpoints. The AST revealed complete absence of resistance to carbapenems while resistance to amikacin was observed at a low level in isolates from dogs (1.6%) and cats (1.5%) compared to horses (10.7%). Among dog isolates, resistance to fluoroquinolones ranged from 9.1%-9.3% whereas among cat isolates, it ranged from 3.2%-5%. Among dog isolates, the proportion showing a 3rd generation cephalosporin (3GC) non-wild type phenotype was significantly higher (Presistance was 18.1%, 11.7% and 42.9% in dog, cat and horse isolates, respectively. Risk factor analysis revealed that MDR E. coli isolated from UTI were positively associated with chronicity of infection and previous antimicrobial treatment. Dogs and cats with chronic UTI that had been previously treated with antimicrobials were eight times and six times more likely to be infected with MDR E. coli compared to dogs and cats with non-chronic UTI, and no history of antimicrobial treatment, respectively. This study revealed that pre-existing disease condition and prior antimicrobial use were the major risks associated with UTI with MDR E. coli in companion animals. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Septic arthritis as the first sign of Candida tropicalis fungaemia in an acute lymphoid leukemia patient

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    Vicari Perla

    2003-01-01

    Full Text Available Fungal infections caused by Candida species have increased in incidence during the past two decades in England, North America and Europe. Candidal arthritis is rare in patients who are not intravenous drug users or are who not using a prostheses. We report the case of a 24-year-old man with acute lymphoid leukemia, who developed Candida tropicalis arthritis during an aplastic period after chemotherapy. This is the eighth case described in the literature of C. tropicalis causing arthritis without intra-articular inoculation. We call attention to an unusual first sign of fungal infection: septic arthritis without intra-articular inoculation. However, this case differs from the other seven, since despite therapy a fast and lethal evolution was observed. We reviewed reported cases, incidence, risk factors, mortality and treatment of neutropenic patients with fungal infections.

  9. Optimized Production of Xylitol from Xylose Using a Hyper-Acidophilic Candida tropicalis

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    Elena Tamburini

    2015-08-01

    Full Text Available The yeast Candida tropicalis DSM 7524 produces xylitol, a natural, low-calorie sweetener, by fermentation of xylose. In order to increase xylitol production rate during the submerged fermentation process, some parameters-substrate (xylose concentration, pH, aeration rate, temperature and fermentation strategy-have been optimized. The maximum xylitol yield reached at 60–80 g/L initial xylose concentration, pH 5.5 at 37 °C was 83.66% (w/w on consumed xylose in microaerophilic conditions (kLa = 2·h−1. Scaling up on 3 L fermenter, with a fed-batch strategy, the best xylitol yield was 86.84% (w/w, against a 90% of theoretical yield. The hyper-acidophilic behaviour of C. tropicalis makes this strain particularly promising for industrial application, due to the possibility to work in non-sterile conditions.

  10. Optimized Production of Xylitol from Xylose Using a Hyper-Acidophilic Candida tropicalis.

    Science.gov (United States)

    Tamburini, Elena; Costa, Stefania; Marchetti, Maria Gabriella; Pedrini, Paola

    2015-08-19

    The yeast Candida tropicalis DSM 7524 produces xylitol, a natural, low-calorie sweetener, by fermentation of xylose. In order to increase xylitol production rate during the submerged fermentation process, some parameters-substrate (xylose) concentration, pH, aeration rate, temperature and fermentation strategy-have been optimized. The maximum xylitol yield reached at 60-80 g/L initial xylose concentration, pH 5.5 at 37 °C was 83.66% (w/w) on consumed xylose in microaerophilic conditions (kLa = 2·h(-1)). Scaling up on 3 L fermenter, with a fed-batch strategy, the best xylitol yield was 86.84% (w/w), against a 90% of theoretical yield. The hyper-acidophilic behaviour of C. tropicalis makes this strain particularly promising for industrial application, due to the possibility to work in non-sterile conditions.

  11. Spondylodiscitis concurrent with infectious aortic aneurysm caused by Candida tropicalis: a case report.

    Science.gov (United States)

    Oichi, Takeshi; Sasaki, Satoru; Tajiri, Yasuhito

    2015-08-01

    We report a case of spondylodiscitis concurrent with infectious aortic aneurysm caused by Candida tropicalis in a 79-year-old immunocompromised man. The patient underwent percutaneous drainage of the abscess and endoluminal exclusion of the aneurysm using a bifurcated stent graft. Micafungin was administered intravenously for 8 weeks, followed by a prolonged course of oral fluconazole. At the one-year follow-up, no recurrence was noted, and the patient could walk with a cane without low back pain.

  12. Ouro proteins are not essential to tail regression during Xenopus tropicalis metamorphosis

    OpenAIRE

    Nakai, Yuya; Nakajima, Keisuke; Robert, Jacques; Yaoita, Yoshio

    2016-01-01

    Tail regression is one of the most prominent transformations observed during anuran metamorphosis. A tadpole tail that is twice as long as the tadpole trunk nearly disappears within three days in Xenopus tropicalis. Several years ago, it was proposed that this phenomenon is driven by an immunological rejection of larval-skin-specific antigens, Ouro proteins. We generated ouro-knockout tadpoles using the TALEN method to reexamine this immunological rejection model. Both the ouro1- and ouro2-kn...

  13. Location of brain lesions predicts conversion of clinically isolated syndromes to multiple sclerosis

    DEFF Research Database (Denmark)

    Giorgio, Antonio; Battaglini, Marco; Rocca, Maria Assunta

    2013-01-01

    : In CIS patients with hemispheric, multifocal, and brainstem/cerebellar onset, lesion probability map clusters were seen in clinically eloquent brain regions. Significant lesion clusters were not found in CIS patients with optic nerve and spinal cord onset. At 1 year, clinically definite MS developed......OBJECTIVES: To assess in a large population of patients with clinically isolated syndrome (CIS) the relevance of brain lesion location and frequency in predicting 1-year conversion to multiple sclerosis (MS). METHODS: In this multicenter, retrospective study, clinical and MRI data at onset...

  14. Antifungal susceptibility testing of Candida species isolated from the immunocompromised patients admitted to ten university hospitals in Iran: comparison of colonizing and infecting isolates.

    Science.gov (United States)

    Badiee, Parisa; Badali, Hamid; Boekhout, Teun; Diba, Kambiz; Moghadam, Abdolkarim Ghadimi; Hossaini Nasab, Ali; Jafarian, Hadis; Mohammadi, Rasoul; Mirhendi, Hossein; Najafzadeh, Mohammad Javad; Shamsizadeh, Ahmad; Soltani, Jafar

    2017-11-21

    Antifungal susceptibility testing is a subject of interest in the field of medical mycology. The aim of the present study were the distributions and antifungal susceptibility patterns of various Candida species isolated from colonized and infected immunocompromised patients admitted to ten university hospitals in Iran. In totally, 846 Candida species were isolated from more than 4000 clinical samples and identified by the API 20 C AUX system. Antifungal susceptibility testing was performed by broth microdilution method according to CLSI. The most frequent Candida species isolated from all patients was Candida albicans (510/846). The epidemiological cutoff value and percentage of wild-type species for amphotericin B and fluconazole in Candida albicans, Candida tropicalis, Candida glabrata and Candida krusei were 0.5 μg/ml (95%) and 4 μg/ml (96%); 1 μg/ml (95%) and 8 μg/ml (95%); 0.5 μg/ml (99%) and 19 μg/ml (98%); and 4 μg/ml (95%) and 64 μg/ml (95%), respectively. The MIC90 and epidemiological cutoff values to posaconazole in Candida krusei were 0.5 μg/ml. There were significant differences between infecting and colonizing isolates of Candida tropicalis in MIC 90 values of amphotericin B, and isolates of Candida glabrata in values of amphotericin B, caspofungin, and voriconazole (P Candida species (colonizing and infecting isolates) in immunocompromised patients are not the same and acquired resistance was seen in some species.

  15. Antifungal susceptibility testing of Candida species isolated from the immunocompromised patients admitted to ten university hospitals in Iran: comparison of colonizing and infecting isolates

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    Parisa Badiee

    2017-11-01

    Full Text Available Abstract Background Antifungal susceptibility testing is a subject of interest in the field of medical mycology. The aim of the present study were the distributions and antifungal susceptibility patterns of various Candida species isolated from colonized and infected immunocompromised patients admitted to ten university hospitals in Iran. Methods In totally, 846 Candida species were isolated from more than 4000 clinical samples and identified by the API 20 C AUX system. Antifungal susceptibility testing was performed by broth microdilution method according to CLSI. Results The most frequent Candida species isolated from all patients was Candida albicans (510/846. The epidemiological cutoff value and percentage of wild-type species for amphotericin B and fluconazole in Candida albicans, Candida tropicalis, Candida glabrata and Candida krusei were 0.5 μg/ml (95% and 4 μg/ml (96%; 1 μg/ml (95% and 8 μg/ml (95%; 0.5 μg/ml (99% and 19 μg/ml (98%; and 4 μg/ml (95% and 64 μg/ml (95%, respectively. The MIC90 and epidemiological cutoff values to posaconazole in Candida krusei were 0.5 μg/ml. There were significant differences between infecting and colonizing isolates of Candida tropicalis in MIC 90 values of amphotericin B, and isolates of Candida glabrata in values of amphotericin B, caspofungin, and voriconazole (P < 0.05. Conclusions Our findings suggest that the susceptibility patterns of Candida species (colonizing and infecting isolates in immunocompromised patients are not the same and acquired resistance was seen in some species.

  16. Carbapenem nonsusceptibility with modified OprD in clinical isolates of Pseudomonas aeruginosa from India

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    Debarati Choudhury

    2017-01-01

    Full Text Available This study was undertaken to investigate OprD porin-mediated carbapenem nonsusceptibility in clinical isolates of Pseudomonas aeruginosa from a tertiary referral hospital of Northeast India. A total of 267 nonduplicate, consecutive clinical isolates of P. aeruginosa were obtained. Mutation and expression levels of OprD gene were determined in carbapenem-nonsusceptible carbapenemase-nonproducing isolates. Among 19 carbapenem-nonsusceptible carbapenemase-nonproducing isolates, 11 of them demonstrated variable band pattern while performing denaturing gradient gel electrophoresis with amplified products of OprD gene. Sequencing of variable band products revealed three mutation patterns in three isolates. Relevant decrease in expression of OprD gene could also be observed in them. All the three isolates exhibited a higher minimum inhibitory concentration for imipenem (64–128 μg/mL compared to meropenem (16–64 μg/mL. Inactivating mutation and decreased expression of OprD contribute mainly to imipenem resistance as well as to meropenem.

  17. Carbapenem nonsusceptibility with modifiedOprDin clinical isolates ofPseudomonas aeruginosafrom India.

    Science.gov (United States)

    Choudhury, Debarati; Talukdar, Anupam Das; Choudhury, Manabendra Dutta; Maurya, Anand Prakash; Chanda, Debadatta Dhar; Chakravorty, Atanu; Bhattacharjee, Amitabha

    2017-01-01

    This study was undertaken to investigate OprD porin-mediated carbapenem nonsusceptibility in clinical isolates of Pseudomonas aeruginosa from a tertiary referral hospital of Northeast India. A total of 267 nonduplicate, consecutive clinical isolates of P. aeruginosa were obtained. Mutation and expression levels of OprD gene were determined in carbapenem-nonsusceptible carbapenemase-nonproducing isolates. Among 19 carbapenem-nonsusceptible carbapenemase-nonproducing isolates, 11 of them demonstrated variable band pattern while performing denaturing gradient gel electrophoresis with amplified products of OprD gene. Sequencing of variable band products revealed three mutation patterns in three isolates. Relevant decrease in expression of OprD gene could also be observed in them. All the three isolates exhibited a higher minimum inhibitory concentration for imipenem (64-128 μg/mL) compared to meropenem (16-64 μg/mL). Inactivating mutation and decreased expression of OprD contribute mainly to imipenem resistance as well as to meropenem.

  18. Susceptibility pattern of extended spectrum beta-lactamase producing isolates in various clinical specimens

    International Nuclear Information System (INIS)

    Roshan, M.

    2011-01-01

    Objective: To determine the susceptibility pattern of extended spectrum beta-lactamase (ESBL) producing Gram negative isolates from various clinical specimens. Study Design: Descriptive study. Place and Duration of Study: Microbiology Department, Armed Forces Institute of Pathology, Rawalpindi, from January 2008 to January 2009. Methodology: A total of 308 ESBL producing isolates from various clinical specimens sent to AFIP for culture and sensitivity were identified using standard microbiological techniques and tested for antimicrobial susceptibility. At the same time screening for ESBL production was also done. ESBL production was confirmed by combination disc synergy method. The susceptibility pattern of isolates was then recorded in frequency percentages. Results: Out of the 308 ESBL producing isolates more than 99% were susceptible to carbapenems, 84% to tazobactam/ piperacillin, 81% to sulbactam/cefoperazone, 12% to fluoroquinolones, 13% to cotrimoxazole, 59% to amikacin and 18% to gentamicin. Among the urinary isolates 49% were susceptible to Nitrofurontoin and only 5% to Pipemidic acid. Conclusion: Antibiotic choices in case of ESBL producing isolates are limited and at present only carbapenems can be regarded as treatment of choice. As empirical agents, beta-lactam/beta lactamase inhibitor combinations should be used cautiously for serious infections. Fluoroquinolones showed very poor efficacy. Amikacin can be used alternatively in such cases. Nitrofurantoin is still a good oral agent for treating UTI. (author)

  19. Characterisation of the first VIM metallo-beta-lactamase-producing Pseudomonas aeruginosa clinical isolate in Serbia.

    Science.gov (United States)

    Lepsanovic, Zorica; Libisch, B; Tomanovic, Branka; Nonkovici, Zorka; Balogh, Boglárka; Füzi, M

    2008-12-01

    From the Central-East European region the first VIM metallo-beta-lactamase (MBL) producing Pseudomonas aeruginosa strains were published from Croatia, Poland and Hungary. The aim of this study was to assess the contribution of MBL-production to carbapenem-resistance among P. aeruginosa clinical isolates in the Military Medical Academy (MMA) in Belgrade, Serbia between August 2004 and September 2007. Only one P. aeruginosa isolate with strain number 722 proved MBL-positive that harboured a novel class 1 integron with a bla(VIM-2)-like cassette in the first position, followed by orfD, a putative gene with unknown function. Our data indicate that MBL-producing strains occur at a prevalence of less than 1% among imipenem-nonsusceptible P. aeruginosa clinical isolates in this Belgrade hospital. The newly identified VIM MBL-producing P. aeruginosa strain 722 could be assigned to serotype O11, and it was panresistant to all antimicrobials tested. The isolate displayed sequence type ST235 by multilocus sequence typing which is the founder sequence type of the previously identified international clonal complex CC11 that already contains bla(VIM)-positive isolates from Italy, Greece, Sweden, Hungary and Poland. In conclusion, this is the first report of VIM MBL-producing P. aeruginosa from Serbia and also of the occurrence of such isolates belonging to the international clonal complex CC11 in this country.

  20. Antimicrobial resistance in clinical Escherichia coli isolates from poultry and livestock, China.

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    Afrah Kamal Yassin

    Full Text Available Poultry and livestock are the most important reservoirs for pathogenic Escherichia coli and use of antimicrobials in animal farming is considered the most important factor promoting the emergence, selection and dissemination of antimicrobial-resistant microorganisms. The aim of our study was to investigate antimicrobial resistance in E. coli isolated from food animals in Jiangsu, China. The disc diffusion method was used to determine susceptibility to 18 antimicrobial agents in 862 clinical isolates collected from chickens, ducks, pigs, and cows between 2004 and 2012. Overall, 94% of the isolates showed resistance to at least one drug with 83% being resistance to at least three different classes of antimicrobials. The isolates from the different species were most commonly resistant to tetracycline, nalidixic acid, sulfamethoxazole, trimethoprim/sulfamethoxazole and ampicillin, and showed increasing resistance to amikacin, aztreonam, ceftazidime, cefotaxime, chloramphenicol, ciprofloxacin. They were least resistant to amoxicillin/clavulanic acid (3.4% and ertapenem (0.2%. MDR was most common in isolates from ducks (44/44, 100%, followed by chickens (568/644, 88.2%, pigs (93/113, 82.3% and cows (13/61, 21.3%. Our finding that clinical E. coli isolates from poultry and livestock are commonly resistant to multiple antibiotics should alert public health and veterinary authorities to limit and rationalize antimicrobial use in China.

  1. Slime production and antibiotic susceptibility in staphylococci isolated from clinical samples

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    Seza Arslan

    2007-02-01

    Full Text Available A total of 187 isolates from several clinical specimens were identified to species level as 129 Staphylococcus aureus strains and 58 coagulase-negative staphylococci (CNS strains by the API Staph System (Biomerieux. Slime production was detected both by the conventional Christensen's method as well as by the Congo red agar method. Seventy-two strains of staphylococci isolates (38.5% were found to be slime producers by Christensen's test tube method whereas 58 strains (31% were slime positive with Congo red agar method. There was no statistically significant difference between the two methods for the detection of slime production (P > 0.05. Susceptibility of isolates against antimicrobial agents was tested by the disk diffusion method. Staphylococcal species had resistance to one or more antibiotics. Among the various antimicrobial agents, oxacillin (71.1% and erythromycin (47.1% showed higher resistance than most of the agents used against all isolates. Oxacillin resistant S. aureus (ORSA and oxacillin resistant coagulase-negative staphylococci (ORCNS, 97 (75.2% and 36 (62.1% respectively were frequently observed in strains isolated from clinical materials. Among the ORSA strains, two strains were resistant to vancomycin. Moreover, 96 (74.4% of 129 S. aureus strains were positive for blactamase enzyme. However, 78 (81.25% of 96 b-lactamase positive S. aureus strains were b-lactamase positive ORSA isolates, but none of them had vancomycin resistance.

  2. Assessment of AmpC Beta-Lactamase Genes among Clinical Escherichia coli Isolates

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    HedrooshaMolla Agha-Mirzaeie

    2015-11-01

    Full Text Available Background: AmpC bta lactamases play a significant role in creating resistance to third generation cephalosporins worldwide. They mostly express on chromosome of Enterobacteriaceae especially Escherichia coli and cause consequential problem inclinical treatment and lead to failure in diagnosis and phenotypic test recommended byClinical and Laboratory Standards Institute.Methods:Totally 200 E. coli isolates from different hospitals of Tehran were collected. The isolates were screened by disk diffusion method according to the CLSI guidelines. The profiles and prevalence surveys of AmpC (Dha, CITM, Mox and FOX-type β-lactamase genes in clinical isolates of E. coli by phenotypic and molecular methods.  Results:Out of 200 Ecoli isolated, 115 (89.8% and 13 (10.2% isolates were identified as ESBL- and AmpC- beta-lactamase producers, respectively. Among mpC producers, 13 (100% and 5 (38.5% isolates was reported by PCR assay as bla-CITM and Dha respectively. Mox and FOX genes were not detected in any sample.Conclusions:Our results highlight the importance of using molecular detection methods to identify β-lactamase-producer that have resistance to antibiotics. 

  3. Contribution of different mechanisms to the resistance to fluoroquinolones in clinical isolates of Salmonella enterica

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    Abeer Ahmed Rushdy

    Full Text Available OBJECTIVES: To study the potential factors include gene mutation, efflux pump and alteration of permeability associated with quinolone-resistance of Salmonella enterica strains isolated from patients with acute gastroenteritis and to evaluate the degree of synergistic activity of efflux pump inhibitors when combined with ciprofloxacin against resistant isolates. METHODS: Antimicrobial resistance patterns of fifty-eight Salmonella isolates were tested. Five isolates were selected to study the mechanism of resistance associated with quinolone group, including mutation in topoisomerase-encoding gene, altered cell permeability, and expression of an active efflux system. In addition, the combination between antibiotics and efflux pump inhibitors to overcome the microbial resistance was evaluated. RESULTS: Five Salmonella isolates totally resistant to all quinolones were studied. All isolates showed alterations in outer membrane proteins including disappearance of some or all of these proteins (Omp-A, Omp-C, Omp-D and Omp-F. Minimum inhibitory concentration values of ciprofloxacin were determined in the presence/absence of the efflux pump inhibitors: carbonyl cyanide m-chlorophenylhydrazone, norepinephrin and trimethoprim. Minimum inhibitory concentration values for two of the isolates were 2-4 fold lower with the addition of efflux pump inhibitors. All five Salmonella isolates were amplified for gyrA and parC genes and only two isolates were sequenced. S. Enteritidis 22 had double mutations at codon 83 and 87 in addition to three mutations at parC at codons 67, 76 and 80 whereas S. Typhimurium 57 had three mutations at codons 83, 87 and 119, but no mutations at parC. CONCLUSIONS: Efflux pump inhibitors may inhibit the major AcrAB-TolC in Salmonella efflux systems which are the major efflux pumps responsible for multidrug resistance in Gramnegative clinical isolates.

  4. First report on blaNDM-1-producing Acinetobacter baumannii in three clinical isolates from Ethiopia.

    Science.gov (United States)

    Pritsch, Michael; Zeynudin, Ahmed; Messerer, Maxim; Baumer, Simon; Liegl, Gabriele; Schubert, Soeren; Löscher, Thomas; Hoelscher, Michael; Belachew, Tefara; Rachow, Andrea; Wieser, Andreas

    2017-03-01

    Multidrug-resistant Gram-negative bacterial infections are recognized as one of the major threats to global health. In this study, we describe for the first time bla NDM-1 gene carrying organisms from Ethiopia consisting of three Acinetobacter baumannii isolates from patients in Jimma. Besides phenotypic antimicrobial susceptibility testing, molecular strain typing and sequencing was performed to describe the phylogenetic relation of the Ethiopian isolates in detail in relation to published isolates from all over the globe. Three multi-resistant, bla NDM-1 -positive Acinetobacter baumannii isolates, most likely a local clonal diffusion, were isolated. Two of the three isolates described within this study were untreatable with the locally available antimicrobials and were only susceptible to polymyxin B and amikacin. The genome sequences confirmed the isolates to be distinct from the outbreak strains reported from Kenya, the only other characterized bla NDM-1 positive Acinetobacter baumannii strains in East Africa so far. Up to date, no other bacterial species were found to harbour the gene cassette in Jimma and conjugation to E. coli was not successful under laboratory conditions. However, natural transmission to other bacteria seems likely, given the evident lack of hygienic precautions due to limited resource settings. The detected isolates could solely be the tip of the iceberg regarding the presence of NDM-1 producing organisms in the region, as only a limited number of bacterial isolates were evaluated so far and until recently, susceptibility testing and isolation of bacteria could hardly be performed in clinical patient care. These multi-drug resistant organisms pose a serious threat to antimicrobial treatments in Jimma, Ethiopia.

  5. Species-specific detection of Candida tropicalis using evolutionary conserved intein DNA sequences.

    Science.gov (United States)

    Rajasekharan, S K; Ray, A K; Ramesh, S; Kannappan Mohanvel, S

    2018-02-10

    Inteins (internal proteins) are self-splicing transportable genetic elements present in conserved regions of housekeeping genes. The study highlights the importance of intein as a potential diagnostic marker for species-specific identification of Candida tropicalis, a rapidly emerging opportunistic human pathogen. Initial steps of primer validation, sequence alignment, phylogenetic tree analysis, gel electrophoresis and real-time polymerase chain reaction (PCR) assays were performed to confirm the specificity of the designed primers. The primers were selective for C. tropicalis with 100% inclusivity and showed no cross-species or cross-genera matches. The established technique is a prototype for developing multifaceted PCR assays and for point-of-care testing in near future. Development of molecular markers for specific detection of microbial pathogens using real-time polymerase chain reaction (PCR) is an appealing and challenging technique. A real-time PCR is an emerging technology frequently used to detect the aetiologic agents. In recent times, designing species-specific primers for pathogen detection is gaining momentum. The method offers rapid, accurate and cost-effective strategy to identify the target, thus providing sufficient time to instigate appropriate chemotherapy. The study highlights the use of intein DNA sequence as molecular markers for species-specific identification of Candida tropicalis. The study also offers a prototype model for developing multifaceted PCR assays using intein DNA sequences, and provides a developmental starting point for point-of-care testing in near future. © 2018 The Society for Applied Microbiology.

  6. Coexistence of Y, W, and Z sex chromosomes in Xenopus tropicalis

    Science.gov (United States)

    Roco, Álvaro S.; Olmstead, Allen W.; Degitz, Sigmund J.; Amano, Tosikazu; Zimmerman, Lyle B.; Bullejos, Mónica

    2015-01-01

    Homomorphic sex chromosomes and rapid turnover of sex-determining genes can complicate establishing the sex chromosome system operating in a given species. This difficulty exists in Xenopus tropicalis, an anuran quickly becoming a relevant model for genetic, genomic, biochemical, and ecotoxicological research. Despite the recent interest attracted by this species, little is known about its sex chromosome system. Direct evidence that females are the heterogametic sex, as in the related species Xenopus laevis, has yet to be presented. Furthermore, X. laevis’ sex-determining gene, DM-W, does not exist in X. tropicalis, and the sex chromosomes in the two species are not homologous. Here we identify X. tropicalis’ sex chromosome system by integrating data from (i) breeding sex-reversed individuals, (ii) gynogenesis, (iii) triploids, and (iv) crosses among several strains. Our results indicate that at least three different types of sex chromosomes exist: Y, W, and Z, observed in YZ, YW, and ZZ males and in ZW and WW females. Because some combinations of parental sex chromosomes produce unisex offspring and other distorted sex ratios, understanding the sex-determination systems in X. tropicalis is critical for developing this flexible animal model for genetics and ecotoxicology. PMID:26216983

  7. Detoxification of Corncob Acid Hydrolysate with SAA Pretreatment and Xylitol Production by Immobilized Candida tropicalis

    Science.gov (United States)

    Deng, Li-Hong; Tang, Yong; Liu, Yun

    2014-01-01

    Xylitol fermentation production from corncob acid hydrolysate has become an attractive and promising process. However, corncob acid hydrolysate cannot be directly used as fermentation substrate owing to various inhibitors. In this work, soaking in aqueous ammonia (SAA) pretreatment was employed to reduce the inhibitors in acid hydrolysate. After detoxification, the corncob acid hydrolysate was fermented by immobilized Candida tropicalis cell to produce xylitol. Results revealed that SAA pretreatment showed high delignification and efficient removal of acetyl group compounds without effect on cellulose and xylan content. Acetic acid was completely removed, and the content of phenolic compounds was reduced by 80%. Furthermore, kinetic behaviors of xylitol production by immobilized C. tropicalis cell were elucidated from corncob acid hydrolysate detoxified with SAA pretreatment and two-step adsorption method, respectively. The immobilized C. tropicalis cell showed higher productivity efficiency using the corncob acid hydrolysate as fermentation substrate after detoxification with SAA pretreatment than by two-step adsorption method in the five successive batch fermentation rounds. After the fifth round fermentation, about 60 g xylitol/L fermentation substrate was obtained for SAA pretreatment detoxification, while about 30 g xylitol/L fermentation substrate was obtained for two-step adsorption detoxification. PMID:25133211

  8. Detoxification of Corncob Acid Hydrolysate with SAA Pretreatment and Xylitol Production by Immobilized Candida tropicalis

    Directory of Open Access Journals (Sweden)

    Li-Hong Deng

    2014-01-01

    Full Text Available Xylitol fermentation production from corncob acid hydrolysate has become an attractive and promising process. However, corncob acid hydrolysate cannot be directly used as fermentation substrate owing to various inhibitors. In this work, soaking in aqueous ammonia (SAA pretreatment was employed to reduce the inhibitors in acid hydrolysate. After detoxification, the corncob acid hydrolysate was fermented by immobilized Candida tropicalis cell to produce xylitol. Results revealed that SAA pretreatment showed high delignification and efficient removal of acetyl group compounds without effect on cellulose and xylan content. Acetic acid was completely removed, and the content of phenolic compounds was reduced by 80%. Furthermore, kinetic behaviors of xylitol production by immobilized C. tropicalis cell were elucidated from corncob acid hydrolysate detoxified with SAA pretreatment and two-step adsorption method, respectively. The immobilized C. tropicalis cell showed higher productivity efficiency using the corncob acid hydrolysate as fermentation substrate after detoxification with SAA pretreatment than by two-step adsorption method in the five successive batch fermentation rounds. After the fifth round fermentation, about 60 g xylitol/L fermentation substrate was obtained for SAA pretreatment detoxification, while about 30 g xylitol/L fermentation substrate was obtained for two-step adsorption detoxification.

  9. Cloning, expression and purification of squalene synthase from Candida tropicalis in Pichia pastoris.

    Science.gov (United States)

    Lee, Pey Yee; Yong, Voon Chen; Rosli, Rozita; Gam, Lay Harn; Chong, Pei Pei

    2014-02-01

    Squalene synthase (SS) is the key precursor and first committed enzyme of the sterol biosynthesis pathway. In a previous work, SS has been identified as one of the immunogenic proteins that could be a potential diagnostic candidate for the pathogenic fungus Candida tropicalis. In this study, SS from C. tropicalis was cloned and expressed as recombinant protein in Pichia pastoris to investigate its reactivity with serum antibodies. ERG9 gene that encodes for SS was amplified by PCR and cloned in-frame into pPICZB expression vector. The recombinant construct was then transformed into P. pastoris GS115 host strain. Expression of the recombinant protein was confirmed by SDS-PAGE and Western blot analysis using anti-His tag probe. Optimal protein production was achieved by cultivating the culture with 1.0% methanol for 72h. The recombinant protein was purified to approximately 97% pure in a single step immobilized metal affinity chromatography with a yield of 70.3%. Besides, the purified protein exhibited specific reactivity with immune sera on Western blot. This is the first report on heterologous expression of antigenic SS from C. tropicalis in P. pastoris which can be exploited for large-scale production and further research. The results also suggested that the protein might be of great value as antigen candidate for serodiagnosis of Candida infection. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Genotyping of the MTL loci and susceptibility to two antifungal agents of Candida glabrata clinical isolates

    Directory of Open Access Journals (Sweden)

    María Teresa Lavaniegos-Sobrino

    2009-08-01

    Full Text Available The opportunistic fungal pathogen Candida glabrata is the second most common isolate from bloodstream infections worldwide and is naturally less susceptible to the antifungal drug fluconazole than other Candida species. C. glabrata is a haploid yeast that contains three mating-type like loci (MTL, although no sexual cycle has been described. Strains containing both types of mating information at the MTL1 locus are found in clinical isolates, but it is thought that strains containing type a information are more common. Here we investigated if a particular combination of mating type information at each MTLlocus is more prevalent in clinical isolates from hospitalized patients in Mexico and if there is a correlation between mating information and resistance to fluconazole and 5-fluorocytosine. We found that while both types of information at MTL1 are equally represented in a collection of 64 clinical isolates, the vast majority of isolates contain a-type information at MTL2 and α-type at MTL3. We also found no correlation of the particular combination of mating type information at the three MTL loci and resistance to fluconazole.

  11. In Vitro Antifungal Susceptibility of Neoscytalidium dimidiatum Clinical Isolates from Malaysia.

    Science.gov (United States)

    James, Jasper Elvin; Santhanam, Jacinta; Lee, Mei Chen; Wong, Choon Xian; Sabaratnam, Parameswari; Yusoff, Hamidah; Tzar, Mohd Nizam; Razak, Mohd Fuat Abdul

    2017-04-01

    Neoscytalidium dimidiatum is an opportunistic fungus causing cutaneous infections mostly, which are difficult to treat due to antifungal resistance. In Malaysia, N. dimidiatum is associated with skin and nail infections, especially in the elderly. These infections may be mistaken for dermatophyte infections due to similar clinical appearance. In this study, Neoscytalidium isolates from cutaneous specimens, identified using morphological and molecular methods (28 Neoscytalidium dimidiatum and 1 Neoscytalidium sp.), were evaluated for susceptibility towards antifungal agents using the CLSI broth microdilution (M38-A2) and Etest methods. Amphotericin B, voriconazole, miconazole and clotrimazole showed high in vitro activity against all isolates with MIC ranging from 0.0313 to 1 µg/mL. Susceptibility towards fluconazole and itraconazole was noted in up to 10% of isolates, while ketoconazole was inactive against all isolates. Clinical breakpoints for antifungal drugs are not yet available for most filamentous fungi, including Neoscytalidium species. However, the results indicate that clinical isolates of N. dimidiatum in Malaysia were sensitive towards miconazole, clotrimazole, voriconazole and amphotericin B, in vitro.

  12. Emergence of Oxacillinases in Environmental Carbapenem-Resistant Acinetobacter baumannii Associated with Clinical Isolates.

    Science.gov (United States)

    Goic-Barisic, Ivana; Hrenovic, Jasna; Kovacic, Ana; Musić, Martina Šeruga

    2016-10-01

    Six carbapenem-resistant isolates of Acinetobacter baumannii were recovered from untreated and treated municipal wastewater of the capital city of Zagreb, Croatia. Molecular identification of environmental isolates of A. baumannii was performed by amplification, sequencing, and phylogenetic analyses of rpoB gene. The presence of bla OXA genes encoding OXA-type carbapenemases (OXA-51-like, OXA-23, and OXA-40-like) was confirmed by multiplex PCR and sequencing. Phylogenetic analyses corroborated the affiliation of detected bla OXA genes to three different clusters and showed association of environmental OXAs with those described from clinical isolates. This result suggests that isolates recovered from municipal wastewater are most probably of clinical origin. Furthermore, the presence of OXA-40-like (OXA-72) in an environmental A. baumannii isolate is reported for the first time. Persistence of A. baumannii harboring the clinically important OXAs in the wastewater treatment process poses a potentially significant source for horizontal gene transfer and implications for wider spread of antibiotic resistance genes.

  13. Iron Uptake Analysis in a Set of Clinical Isolates of Pseudomonas putida

    Science.gov (United States)

    Molina, Lázaro; Geoffroy, Valérie A.; Segura, Ana; Udaondo, Zulema; Ramos, Juan-Luis

    2016-01-01

    Pseudomonas putida strains are frequent inhabitants of soil and aquatic niches and they are occasionally isolated from hospital environments. As the available iron sources in human tissues, edaphic, and aquatic niches are different, we have analyzed iron-uptake related genes in different P. putida strains that were isolated from all these environments. We found that these isolates can be grouped into different clades according to the genetics of siderophore biosynthesis and recycling. The pyoverdine locus of the six P. putida clinical isolates that have so far been completely sequenced, are not closely related; three strains (P. putida HB13667, HB3267, and NBRC14164T) are grouped in Clade I and the other three in Clade II, suggesting possible different origins and evolution. In one clinical strain, P. putida HB4184, the production of siderophores is induced under high osmolarity conditions. The pyoverdine locus in this strain is closely related to that of strain P. putida HB001 which was isolated from sandy shore soil of the Yellow Sea in Korean marine sand, suggesting their possible origin, and evolution. The acquisition of two unique TonB-dependent transporters for xenosiderophore acquisition, similar to those existing in the opportunistic pathogen P. aeruginosa PAO, is an interesting adaptation trait of the clinical strain P. putida H8234 that may confer adaptive advantages under low iron availability conditions. PMID:28082966

  14. Clinical and Diagnostic Aspects of Brucellosis and Antimicrobial Susceptibility of Brucella Isolates in Hamedan, Iran.

    Science.gov (United States)

    Torkaman Asadi, Fatemeh; Hashemi, Seyyed Hamid; Alikhani, Mohammad Yousef; Moghimbeigi, Abbas; Naseri, Zahra

    2017-05-24

    Current drug regimens for brucellosis are associated with relatively high rates of therapeutic failure or relapse. Reduced antimicrobial susceptibility of Brucella spp. has been proposed recently as a potential cause of therapeutic failure. The aim of this study was to evaluate the antibiotic resistance pattern of Brucella melitensis clinical isolates by E-test method in Hamadan, west of Iran. In a 15-month period, all patients with suspected brucellosis were enrolled. Blood specimens were collected for diagnosis of brucellosis by BACTEC system and serological tests. Antimicrobial susceptibility of clinical isolates to 7 antibiotics was assessed by the E-test method. One hundred forty-nine patients with brucellosis were evaluated. 38.3% of cultures of clinical samples were positive for BACTEC system, of which 91.2% were associated with a positive serological test result. No significant associations were found between serology and the culture method. All Brucella isolates were susceptible to doxycycline, streptomycin, gentamicin, ciprofloxacin, and moxifloxacin. However, decreased sensitivity to rifampin and trimethoprim-sulfamethoxazole was found in 35.1% and 3.5% of isolates, respectively. Because of the high rates of intermediate sensitivity to rifampin among Brucella isolates, this drug should be prescribed with caution. We recommend restricting the use of rifampin for treatment of brucellosis except as an alternative drug for special situations.

  15. Attaching and effacing Escherichia coli isolates from Danish children: clinical significance and microbiological characteristics

    DEFF Research Database (Denmark)

    Jensen, C; Ethelberg, S; Olesen, B

    2007-01-01

    This study describes the prevalence, clinical manifestations and microbiological characteristics of attaching and effacing Escherichia coli isolates, i.e., enteropathogenic E. coli (EPEC) belonging to the classical EPEC serotypes, non-EPEC attaching and effacing E. coli (A/EEC) and verocytotoxin......-producing E. coli (VTEC), isolated in a case-control study of Danish children aged EPEC and VTEC were more prevalent in cases (2.4% and 2.6%, respectively) than in controls (0.7% and 0.7%, respectively). There was a high frequency of A....../EEC isolates (n = 121), but these were equally prevalent in cases (11.3%) and controls (12.5%), and comprised a heterogeneous distribution of O:H serotypes. The intimin (eae) subtypes in A/EEC isolates showed an even distribution; the eae-gamma subtype predominated in classical EPEC cases. The virulence genes...

  16. Frequency, virulence genes and antimicrobial resistance of Listeria spp. isolated from bovine clinical mastitis.

    Science.gov (United States)

    Jamali, Hossein; Radmehr, Behrad

    2013-11-01

    The aims of this study were to determine the prevalence, characteristics and antimicrobial resistance of Listeria spp. isolated from bovine clinical mastitis in Iran. Listeria spp. were detected in 21/207 bovine mastitic milk samples from dairy farms in Iran, comprising L. monocytogenes (n=17), L. innocua (n=3) and L. ivanovii (n=1). L. monocytogenes isolates were grouped into serogroups '4b, 4d, 4e', '1/2a, 3a', '1/2b, 3b, 7' and '1/2c, 3c'; all harboured inlA, inlC and inlJ virulence genes. Listeria spp. were most frequently resistant to penicillin G (14/21 isolates, 66.7%) and tetracyclines (11/21 isolates, 52.4%). Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Susceptibility of clinical isolates of Bacteroides fragilis group strains to cefoxitin, cefoperazone and ticarcillin/clavulanate

    Directory of Open Access Journals (Sweden)

    PEIXOTO JÚNIOR Arnaldo Aires

    2000-01-01

    Full Text Available A total of 40 strains of the B. fragilis group was isolated from clinical specimens in two hospital centers in Fortaleza from 1993 to 1997. The most frequently isolated species was Bacteroides fragilis (19 strains and most isolates came from intra-abdominal and wound infections. The susceptibility profile was traced for cefoxitin, cefoperazone and ticarcillin-clavulanate by using the agar dilution reference method. All isolates were susceptible to ticarcillin-clavulanate (128/2mug/ml. Resistance rates of 15 and 70% were detected to cefoxitin (64mug/ml and cefoperazone (64mug/ml, respectively. Such regional results permit a better orientation in choosing this group of antibiotics for prophylaxis and therapy especially in relation to cefoxitin, which is frequently used in the hospital centers studied.

  18. Resistance to penicillin-streptomycin synergy among clinical isolates of viridans streptococci.

    Science.gov (United States)

    Farber, B F; Eliopoulos, G M; Ward, J I; Ruoff, K; Moellering, R C

    1983-01-01

    Viridans streptococci are thought to be highly susceptible to penicillin and streptomycin. We recently encountered a unique group of 15 isolates from South Africa epidemiologically related to the isolation of penicillin-resistant pneumococci. These organisms were highly resistant to penicillin (PCN) (minimal inhibitory concentration, 1 to 32 micrograms/ml) and streptomycin (SM) (minimal inhibitory concentration, greater than or equal to 2,000 micrograms/ml). Two additional organisms with high-level streptomycin resistance were identified when 168 clinical isolates from Boston were screened. Time-kill studies with four organisms resistant to high levels of SM demonstrated lack of synergy between PCN and SM but marked synergy between PCN and gentamicin. Adenylylating, acetylating, and phosphorylating activity could not be detected in three organisms studied, and novobiocin failed to cure the SM resistance. Protein synthesis by ribosomes isolated from these organisms was dramatically reduced in the presence of gentamicin but was relatively resistant to inhibition by SM. PMID:6559052

  19. Phenotypic and genotypic characterization of Vibrio cholerae clinically isolated in Surabaya, Indonesia.

    Science.gov (United States)

    Nishibori, Tomoyuki; de Vries, Garry Cores; Rahardjo, Dadik; Wasito, Eddy Bagus; De, Ismoedijanto; Kinoshita, Shouhiro; Hayashi, Yoshitake; Hotta, Hak; Kawabata, Masato; Shirakawa, Toshiro; Iijima, Yoshio; Osawa, Ro

    2011-01-01

    The phenotypic and genotypic characteristics of 6 clinical strains of Vibrio cholerae isolated in Surabaya, Indonesia in 2009 were examined. The DNA fingerprints obtained suggested that these isolates were not from a single clone. Furthermore, all isolates produced cholera toxin and possessed the classical type of toxin B subunit gene, thus meaning that this is the first report of the occurrence of El Tor variants of V. cholerae in Indonesia. Although all isolates were sensitive to almost all antibiotics tested, including ampicillin, chloramphenicol, ciprofloxacin, gentamicin, levofloxacin, kanamycin, nalidixic acid, norfloxacin, streptomycin, trimethoprim-sulfamethoxazole, and tetracycline, and had no mutation in the gyrA and parC genes, they nevertheless possessed the class 1 integron that is a molecular vehicle for the acquisition of antibiotic resistance genes, suggesting that they have the potential to acquire the genetic element for drug resistance.

  20. Molecular and Clinical Epidemiology of Salmonella Paratyphi A Isolated from Patients with Bacteremia in Nepal.

    Science.gov (United States)

    Sherchan, Jatan Bahadur; Morita, Masatomo; Matono, Takashi; Izumiya, Hidemasa; Ohnishi, Makoto; Sherchand, Jeevan B; Tandukar, Sarmila; Laghu, Ujjwal; Nagamatsu, Maki; Kato, Yasuyuki; Ohmagari, Norio; Hayakawa, Kayoko

    2017-12-01

    Little is known about the epidemiology of typhoid and paratyphoid fever in Nepal. We aimed to elucidate the molecular and clinical epidemiology of Salmonella Paratyphi A in Nepal. Isolates were collected from 23 cases of bacteremia due to S. Paratyphi A between December 2014 and October 2015. Thirteen patients (57%) were male, and the median age was 21 years. None of the patients had an underlying chronic disease. All S. Paratyphi A isolates were sensitive to ampicillin, trimethoprim/sulfamethoxazole, ceftriaxone, and chloramphenicol. All isolates were resistant to nalidixic acid and were categorized as intermediately susceptible to levofloxacin. Phylogenetic analysis revealed close relatedness among the isolates, including several clonal groups, suggesting local spread. Patients with bacteremia due to S. Paratyphi A in Kathmandu, Nepal, were relatively young and nondebilitated. Improving control of S . Paratyphi infections should focus on effective infection control measures and selection of empirical therapy based on current resistance patterns.

  1. Cdr2p contributes to fluconazole resistance in Candida dubliniensis clinical isolates.

    LENUS (Irish Health Repository)

    2011-05-01

    The development of resistance to azole antifungals used in the treatment of fungal infections can be a serious medical problem. Here, we investigate the molecular mechanisms associated with reduced susceptibility to fluconazole in clinical isolates of Candida dubliniensis , showing evidence of the trailing growth phenomenon. The changes in membrane sterol composition were studied in the presence of subinhibitory fluconazole concentrations. Despite lanosterol and eburicol accumulating as the most prevalent sterols after fluconazole treatment, these ergosterol precursors still support growth of Candida isolates. The overexpression of ABC transporters was demonstrated by immunoblotting employing specific antibodies against Cdr1p and Cdr2p. The presence of a full-length 170 kDa protein Cdr1p was detected in two isolates, while a truncated form of Cdr1p with the molecular mass of 85 kDa was observed in isolate 966\\/3(2). Notably, Cdr2p was detected in this isolate, and the expression of this transporter was modulated by subinhibitory concentrations of fluconazole. These results suggest that C. dubliniensis can display the trailing growth phenomenon, and such isolates express similar molecular mechanisms like that of fluconazole-resistant isolates and can therefore be associated with recurrent infections.

  2. Isolation and identification of bacterial causes of clinical mastitis in cattle in Sulaimania region

    Directory of Open Access Journals (Sweden)

    S. A. Hussein

    2008-01-01

    Full Text Available A total of 51 cases of bovine clinical mastitis in Sulaimani district were investigated for their bacteriological causative agents; 76 milk samples were cultured on primary and selective media and the isolated bacteria were tested for their susceptibility to antimicrobial agents used in commercial intramammary infusion products. Eighty two bacterial isolates were obtained and further identified using biochemical tests. Escherichia coli was the most common bacteria followed by Staphylococcus aureus, Streptococcus agalactia and coagulase–negative staphylococci. Two other bacterial species (Pseudomonas aeruginosa and Streptococcucs uberis were also isolated but in a lower proportion. Antibacterial susceptibility testing showed that the use of florfenicol, cephalexin and gentamicin may be useful for the treatment of clinical mastitis cases in cows.

  3. Rapid antimicrobial susceptibility testing of clinical isolates by digital time-lapse microscopy

    DEFF Research Database (Denmark)

    Fredborg, M; Rosenvinge, F S; Spillum, E

    2015-01-01

    (168 antimicrobial agent-organism combinations) demonstrated 3.6 % minor, no major and 1.2 % very major errors of the oCelloScope system compared to conventional susceptibility testing, as well as a rapid and correct phenotypic detection of strains with methicillin-resistant Staphylococcus aureus (MRSA......Rapid antimicrobial susceptibility testing (AST) is essential for early and appropriate therapy. Methods with short detection time enabling same-day treatment optimisation are highly favourable. In this study, we evaluated the potential of a digital time-lapse microscope system, the o......CelloScope system, to perform rapid AST. The oCelloScope system demonstrated a very high accuracy (96 % overall agreement) when determining the resistance profiles of four reference strains, nine clinical isolates, including multi-drug-resistant isolates, and three positive blood cultures. AST of clinical isolates...

  4. Antimicrobial susceptibility of methicillin-resistant Staphylococcus pseudintermedius isolated from veterinary clinical cases in the UK.

    Science.gov (United States)

    Maluping, R P; Paul, N C; Moodley, A

    2014-01-01

    Staphylococcus pseudintermedius is a leading aetiologic agent of pyoderma and other body tissue infections in dogs and cats. In recent years, an increased prevalence of methicillin-resistant S. pseudintermedius (MRSP) has been reported. Isolation of MRSP in serious infections poses a major therapeutic challenge as strains are often resistant to all forms of systemic antibiotic used to treat S. pseudintermedius -related infections. This study investigates the occurrence of MRSP from a total of 7183 clinical samples submitted to the authors' laboratories over a 15-month period. Identification was based on standard microbiological identification methods, and by S. pseudintermedius-specific nuc polymerase chain reaction (PCR). Methicillin resistance was confirmed by PBP2a latex agglutination and mecA PCR. Susceptibility against non-beta-lactam antibiotics was carried out using a disc-diffusion method according to Clinical and Laboratory Standards Institute (CLSI) guidelines. In addition, susceptibility to pradofloxacin--a new veterinary fluoroquinolone--was also investigated. SCCmec types were determined by multiplex PCR. Staphylococcus pseudintermedius was isolated from 391 (5%) samples and 20 were confirmed as MRSP from cases of pyoderma, otitis, wound infections, urinary tract infection and mastitis in dogs only. All 20 isolates were resistant to clindamycin and sulphamethoxazole/trimethoprim. Nineteen were resistant to chloramphenicol, enrofloxacin, gentamicin, marbofloxacin and pradofloxacin; additionally, seven isolates were resistant to tetracycline. Fifteen isolates carried SCCmec type II-III, four isolates had type V and one harboured type IV. To date, only a few scientific papers on clinical MRSP strains isolated from the UK have been published, thus the results from this study would provide additional baseline data for further investigations.

  5. Levofloxacin Efflux and smeD in Clinical Isolates of Stenotrophomonas maltophilia.

    Science.gov (United States)

    Chong, So Young; Lee, Kyungwon; Chung, Hae-Sun; Hong, Seong Geun; Suh, Younghee; Chong, Yunsop

    2017-03-01

    Trimethoprim-sulfamethoxazole is the first-line antimicrobial combination for Stenotrophomonas maltophilia infections. However, allergy or intolerance and increasing resistance limit the use of trimethoprim-sulfamethoxazole. Quinolones can be used as an alternative therapeutic option, but resistance can emerge rapidly during therapy. We analyzed the contribution of SmeABC and SmeDEF efflux pumps to levofloxacin resistance in clinical isolates of S. maltophilia. Nonduplicate clinical isolates of S. maltophilia were collected in 2010 from 11 university hospitals (n = 102). Fifty-five levofloxacin nonsusceptible (minimum inhibitory concentration [MIC] ≥4 μg/ml) and 47 susceptible (MIC ≤2 μg/ml) isolates were tested for efflux pump overexpression. Real-time reverse transcription-PCR was performed for amplification and quantification of smeB, smeC, smeD, and smeF mRNA. To determine which antimicrobials were affected by smeD overexpression, the growth rates of a levofloxacin-susceptible S. maltophilia isolate were compared by measuring absorbance of antimicrobial-supplemented Luria-Bertani broth (LB) cultures with or without triclosan. Significant relationships between sme gene overexpression and resistance were observed for smeD against levofloxacin, smeC and smeF against ceftazidime, and smeC against ticarcillin-clavulanate. The mean MICs of moxifloxacin and tigecycline did not significantly differ for isolates with or without overexpression of smeB, smeC, and smeF, but were significantly higher for isolates with smeD overexpression. The mean MICs of amikacin were significantly higher for smeC or smeF overexpressing isolates. Increased growth of a levofloxacin-susceptible isolate was observed in LB with 1/2 MIC levofloxacin in the presence of triclosan. These data suggest that the expression of smeD plays a role in levofloxacin resistance in S. maltophilia.

  6. Characterization of clinical and environmental Mycobacterium avium spp. isolates and their interaction with human macrophages

    Science.gov (United States)

    Members of the Mycobacterium avium complex (MAC) are naturally occurring bacteria in the environment. A link has been suggested between M. avium strains in drinking water and clinical isolates from infected individuals. There is a need to develop new screening methodologies tha...

  7. Sensitivity patterns of pseudomonas aeruginosa isolates obtained from clinical specimens in peshawar

    International Nuclear Information System (INIS)

    Abbas, S.H.; Khan, M.Z.U.; Naeem, M.

    2015-01-01

    Pseudomonas aeruginosa (P. aeruginosa) is a highly virulent opportunistic pathogen and a leading cause of nosocomial infections.Affected patients are often hospitalized in an intensive care unit, and are immuno-compromised as a result of disease and treatment. Suspected P. aeruginosa require timely, adequate and empirical antibiotic therapy to ensure improved outcomes. The purpose of the study was to find the sensitivity and resistance pattern of P. aeruginosa to various groups of drugs, in clinical isolates collected from two major tertiary care hospitals of Peshawar. Methods: Different clinical isolate were taken from patients admitted in various wards of Khyber Teaching Hospital and Lady Reading Hospital Peshawar. Results: A total of 258 clinical isolates were positive for P. aeruginosa out of 2058 clinical isolates. Pseudomonas showed high degree of resistance to third generation Cephalosporins (Ceftazidime, and Ceftriaxone) and moderate degree of resistance to Quinolones and Aminoglycosides (Ofloxacin, Ciprofloxacin, Levofloxacin and Amikacin). Low resistance was observed to different combinations (Cefoperazone + Sulbactum, Piperacillin + Tazobactum). Meropenem and Imipenem had negligible resistance. Conclusion: There is growing resistance to different classes of antibiotics. Combination drugs are useful approach for empirical treatment in suspected Pseudomonas infection. Imipenem and Meropenem are extremely effective but should be in reserve. (author)

  8. Effect of kunnu-zaki on clinical bacteria isolates | Olaitan | African ...

    African Journals Online (AJOL)

    Ten clinical isolates of Gram-negative bacteria were exposed in agar-cup diffusion sensitivity test to Kunun-zaki, a non-alcoholic fermented beverage, taken from eighteen samples. The undiluted samples of the beverage appreciably inhibited the growth of all the bacteria tested including, remarkably, Pseudomonas ...

  9. Emergence of VIM-2 metallo-beta-lactamase producing Ralstonia pickettii clinical isolate in India

    Directory of Open Access Journals (Sweden)

    A Khajuria

    2014-01-01

    Full Text Available A multidrug-resistant clinical isolate of Ralstonia pickettii from a woman was analysed. Modified Hodge test was positive for carbapenemase production. Conjugation experiment revealed the presence of conjugative plasmid of >140 Kb size typed as IncN type. This is the first report of emergence blaVIM-2 in R. pickettii in India.

  10. Isolation and drug sensitivity of micro-organisms from clinical bovine ...

    African Journals Online (AJOL)

    Isolation and drug sensitivity of micro-organisms from clinical bovine mastitis in Zambia. G. S. Pandey, L. M. Tuchili, Y. Sato, M. M. Musonda, K. Kobayashi. Abstract. (Journal of Science and Technology: 1997 1(1): 33-39). Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  11. Attaching and effacing Escherichia coli isolates from Danish children: clinical significance and microbiological characteristics

    DEFF Research Database (Denmark)

    Jensen, C; Ethelberg, S; Olesen, B

    2007-01-01

    This study describes the prevalence, clinical manifestations and microbiological characteristics of attaching and effacing Escherichia coli isolates, i.e., enteropathogenic E. coli (EPEC) belonging to the classical EPEC serotypes, non-EPEC attaching and effacing E. coli (A/EEC) and verocytotoxin...

  12. Detection of Genes for Superantigen Toxins in Methicillin-Resistant Staphylococcus aureus Clinical Isolates in Karachi

    International Nuclear Information System (INIS)

    Taj, Y.; Fatima, I.; Ali, S. W.; Kazmi, S. U.

    2014-01-01

    Objective: To detect genes for enterotoxins, exfoliative and toxic shock syndrome toxins in Staphylococcus aureus (S. aureus) strains isolated from clinical specimens. Study Design: Cross-sectional observational study. Place and Duration of Study: Department of Molecular Genetics, Dr. Ziauddin Hospital, Karachi, from January to December 2010. Methodology: Two hundred and ninety eight S. aureus clinical isolates were obtained from various clinical samples received at Dr. Ziauddin Hospital, Karachi. Out of these, 115 were detected as methicillin resistant (MRSA) by cefoxitin disk diffusion test showing a prevalence rate of 38.6%. Detection of individual toxin genes was performed by Polymerase Chain Reaction (PCR) by using only one primer pair for each tube. Uniplex primers were preferred as multiplex primers are longer in base pairs and have the potential for cross reaction due to non-specific binding and increase in optimization time. Results: The possession of a single gene or more than a single gene in MRSA isolates was found in 61.73% of clinical samples; the highest number was found in pus swab, followed by sputum, blood, urethral swab, and urine. The prevalence of toxin genes was higher in MRSA as compared to methicillin sensitive (MSSA) isolates (19.12%). Conclusion: PCR detects strains possessing toxin genes independent of their expression. The possession of genes for super-antigens seems to be a frequent and habitual trait of S. aureus more so in MRSA. (author)

  13. Clinical and microbiological characterization of Staphylococcus lugdunensis isolates obtained from clinical specimens in a hospital in China

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    Liu Chaojun

    2012-08-01

    Full Text Available Abstract Background Several reports have associated Staphylococcus lugdunensis with the incidence of severe infection in humans; however, the frequency and prevalence of this microorganism and thus the propensity of its antimicrobial drug resistance is unknown in China. The objective of the current study was to determine the prevalence of Staphylococcus lugdunensis among six hundred and seventy non-replicate coagulase negative Staphylococcus (CoNS isolates collected in a 12-month period from clinical specimens in the General Hospital of the People’s Liberation Army in Beijing, China. Results Five (0.7% of the 670 isolates of CoNS were identified as S. lugdunensis. Whereas three isolates were resistant to erythromycin, clindamycin, and penicillin and carried the ermC gene and a fourth one was resistant to cefoxitin and penicillin and carried the mecA gene, one isolate was not resistant to any of the tested antimicrobials. Pulse field gel electrophoretic analysis did not reveal widespread epidemiological diversity of the different isolates. Conclusion Hence, even though S. lugdunensis may be yet unrecognized and undefined in China, it still might be the infrequent cause of infection and profound multi-drug resistance in the same population.

  14. Molecular Characterization of Reduced Susceptibility to Biocides in Clinical Isolates of Acinetobacter baumannii

    Directory of Open Access Journals (Sweden)

    Fei Lin

    2017-09-01

    Full Text Available Active efflux is regarded as a common mechanism for antibiotic and biocide resistance. However, the role of many drug efflux pumps in biocide resistance in Acinetobacter baumannii remains unknown. Using biocide-resistant A. baumannii clinical isolates, we investigated the incidence of 11 known/putative antimicrobial resistance efflux pump genes (adeB, adeG, adeJ, adeT1, adeT2, amvA, abeD, abeM, qacE, qacEΔ1, and aceI and triclosan target gene fabI through PCR and DNA sequencing. Reverse transcriptase quantitative PCR was conducted to assess the correlation between the efflux pump gene expression and the reduced susceptibility to triclosan or chlorhexidine. The A. baumannii isolates displayed high levels of reduced susceptibility to triclosan, chlorhexidine, benzalkonium, hydrogen peroxide, and ethanol. Most tested isolates were resistant to multiple antibiotics. Efflux resistance genes were widely distributed and generally expressed in A. baumannii. Although no clear relation was established between efflux pump gene expression and antibiotic resistance or reduced biocide susceptibility, triclosan non-susceptible isolates displayed relatively increased expression of adeB and adeJ whereas chlorhexidine non-susceptible isolates had increased abeM and fabI gene expression. Increased expression of adeJ and abeM was also demonstrated in multiple antibiotic resistant isolates. Exposure of isolates to subinhibitory concentrations of triclosan or chlorhexidine induced gene expression of adeB, adeG, adeJ and fabI, and adeB, respectively. A point mutation in FabI, Gly95Ser, was observed in only one triclosan-resistant isolate. Multiple sequence types with the major clone complex, CC92, were identified in high level triclosan-resistant isolates. Overall, this study showed the high prevalence of antibiotic and biocide resistance as well as the complexity of intertwined resistance mechanisms in clinical isolates of A. baumannii, which highlights the

  15. Study on some characteristics of Staphylococci isolated from sheep sub clinical mastitis milk in Shahrekord, Iran

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    Azizollah Ebrahimi

    2014-01-01

    Full Text Available Introduction: Staphylococci release a large number of enzymes. Some of these, such as coagulase, beta lactamase, hemolysins and biofilms are considered indices of pathogenicity. The aim of the current study was based on the isolation and identification of Staphylococcus aureus and coagulase negative Staphylococci (CNS strains from sheep sub clinical mastitis and examining their biofilm, beta lactamase, hemolysins production and antibiotic resistance pattern. Materials and methods: 55 Staphylococci strains were isolated from seventy cases of sheep subclinical mastitis. Thirty three were determined as Staphylococcus aureus (60% and 22 (40% as CNS. The hemolytic activity was evaluated by plating Staphylococci strains on 5% bovine blood agar. The biofilm assay was performed by using micro titer plates. Beta Lactamase production was detected by test tube iodometric technique and susceptibility to antimicrobial agents was determined for isolated strains by the disk diffusion method. Results: Twenty six (78.8% S. aureus strains were biofilm producers. For CNS (59.9% strains were positive in biofilm production. Two isolates (6.06%, of S. aureus were α, the same number β and 6 (18.2% isolates were ∂ hemolysin producers. Six isolates of CNS (27.27% were α and ten (45.45% ∂ hemolysin producers. Sixteen S. aureus (48.5% and five CNS (22.72% isolates were positive in beta lactamase production. The isolated Staphylococci show a low sensitivity pattern to methicillin and streptomycin. Discussion and conclusion: A high percentage of strains make α toxin that play a role in S. aureus biofilm formation. Twenty one out of 33 (63.63% isolated Staphylococci were biofilm producers that can have deleterious effects because biofilm formation is thought to play an important role in the survival of virulent strains of Staphylococci. Sixteen out of 33 (48.5% isolated S. aureus were positive in beta lactamase test, Excluding resistant to methicillin, all of these

  16. Generalized Growth of Estuarine, Household and Clinical Isolates of Pseudomonas aeruginosa

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    Kelly E. Diaz

    2018-02-01

    Full Text Available Pseudomonas aeruginosa is an opportunistic pathogen of particular concern to immune-compromised people, such as cystic fibrosis patients and burn victims. These bacteria grow in built environments including hospitals and households, and in natural environments such as rivers and estuaries. However, there is conflicting evidence whether recent environments like the human lung and open ocean affect P. aeruginosa growth performance in alternate environments. We hypothesized that bacteria recently isolated from dissimilar habitats should grow differently in media containing artificial versus natural resources. To test this idea, we examined growth of P. aeruginosa isolates from three environments (estuary, household, and clinic in three media types: minimal-glucose lab medium, and media prepared from sugar maple leaves or big bluestem grass. We used automated spectrophotometry to measure high-resolution growth curves for all isolate by media combinations, and studied two fitness parameters: growth rate and maximum population density. Results showed high variability in growth rate among isolates, both overall and in its dependence on assay media, but this variability was not associated with habitat of isolation. In contrast, total growth (change in absorbance over the experiment differed overall among habitats of isolation, and there were media-specific differences in mean total growth among habitats of isolation, and in among-habitat variability in the media-specific response. This was driven primarily by greater total growth of estuary isolates when compared with those from other habitats of origin, and greater media-specific variability among household isolates than those from other habitats of origin. Taken together, these results suggest that for growth rate P. aeruginosa bacteria appear to be broad generalists without regard to current or recent habitat, whereas for total growth a signature of recent ecological history can be detected.

  17. Inducible clindamycin resistance in clinical isolates of Staphylococcus aureus due to erm genes, Iran.

    Science.gov (United States)

    Moosavian, Mojtaba; Shoja, Saeed; Rostami, Soodabeh; Torabipour, Maryam; Farshadzadeh, Zahra

    2014-12-01

    Resistance to macrolide can be mediated by erm and msrA genes in Staphylococcus aureus. There are the evidences that show erm genes may be causative agent of inducible or constitutive resistance. The aim of this study was to investigate the incidence of inducible clindamycin resistance and determine the most frequency of erm and msrA genes among S. aureus isolates. In this study a total of 124 non duplicated clinical isolates of S. aureus were tested with disk diffusion method. All isolates were tested by PCR for mecA, ermA, ermB, ermC and msrA genes. According to PCR results, 48.4% had mecA gene and 51.6% were mecA negative. By phenotypic D-test method, 32.3% revealed inducible resistance and recorded as D and D(+). Sensitive and constitutive phenotypes were found in 54.8% and 12.9% of isolates respectively. Inducible clindamycin resistance was more prevalent in MRSA (29%) than MSSA isolates (2.4%). Among studied erm genes, the most frequency genes were ermA and ermC with 41.1% and 17.7% respectively. Three isolates of them had D phenotype, while the PCR results of erm genes were negative. All isolates were negative for ermB or msrA genes. Since S. aureus isolates with inducible resistance may mutate and change to constitutive resistance, to prevent treatment failure, we suggest that inducible resistance test be performed on erythromycin resistant/clindamycin sensitive isolates.

  18. Molecular characterization of β-lactamase genes in clinical isolates of carbapenem-resistant Acinetobacter baumannii.

    Science.gov (United States)

    Raible, Kevin M; Sen, Bhaswati; Law, Nancy; Bias, Tiffany E; Emery, Christopher L; Ehrlich, Garth D; Joshi, Suresh G

    2017-11-16

    Acinetobacter baumannii is a nosocomial pathogen which is establishing as a major cause of morbidity and mortality within the healthcare community. The success of this pathogen is largely due to its ability to rapidly gain resistance to antimicrobial therapies and its capability to persist in an abiotic environment through the production of a biofilm. Our tertiary-care hospital has showed high incidence of carbapenem-resistant Acinetobacter baumannii (CRAB) isolates. In this study we explore both genotypic and phenotypic properties of 26 CRAB isolates: 16 isolates were collected from January 2010 to March 2011, and 10 were collected between February and May 2015. We determined that all 26 CRAB isolates possessed multiple β-lactamase genes, including genes from Groups A, C, and D. Specifically, 42% of the isolates possesses the potentially plasmid-borne genes of OXA-23-like or OXA-40-like β-lactamase. The presence of mobile gene element integron cassettes and/or integrases in 88% of the isolates suggests a possible mechanism of dissemination of antibiotic resistance genes. Additionally, the location of insertion sequence (IS) ISAba1 in promotor region of of the OXA-51-like, ADC-7, and ampC genes was confirmed. Multilocus sequence typing (MLST) demonstrated that all 26 CRAB isolates were either sequence type (ST)-229 or ST-2. Interestingly, ST-2 went from being the minority CRAB strain in the 2010-2011 isolates to the predominant strain in the 2015 isolates (from 32 to 90%). We show that the ST-2 strains have an enhanced ability to produce biofilms in comparison to the ST-229 strains, and this fact has potentially led to more successful colonization of the clinical environment over time. This study provides a longitudinal genetic and phenotypic survey of two CRAB sequence types, and suggests how their differing phenotypes may interact with the selective pressures of a hospital setting effecting strain dominance over a 5-year period.

  19. Frequency of Reduced Vancomycin Susceptibility among Clinical Staphylococcus aureus Isolated in Ahvaz Iran

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    Mojtaba Moosavian

    2015-11-01

    Full Text Available Introduction:   One   of   the   most   important   agents   in   hospital-acquired   infections   is Staphylococcus aureus. Treatment of methicillin-resistant S. aureus (MRSA infections with decreased susceptibility to vancomycin has recently been more difficult. The aim of this study was to evaluate the possible presence of vancomycin intermediate S. aureus (VISA and vancomycin- resistant S. aureus (VRSA and also to determine the frequency of MRSA in clinical specimens.Methods: In this study, 195 S. aureus isolates were collected from the patients were examined. All of the isolates were identified using standard biochemical tests.  Susceptibility of S. aureus isolates against 10 antibiotics was detected by disk diffusion method and was followed by E-test and vancomycin screen agar methods. Minimum inhibitory concentration (MIC of vancomycin was determined according to the CLSI guidelines.  Also, detection of mecA gene was performed by PCR and finally, the results were compared.Results: All of the isolates were susceptible to vancomycin (i.e. MIC range of vancomycin was between 0.25-2 µg/ml. Out of 195 S. aureus isolates, 99 isolates (50.8% were resistant to methicillin, and mecA gene was detected in 96 isolates. These results also showed that the highest and lowest resistance rate of isolates was to penicillin (96.9% and chloramphenicol (0%, respectively.Conclusion: Our findings showed that vancomycin can still be used as a valuable drug for treatment of S. aureus infections in our region. However, periodic evaluation of vancomycin MIC of S. aureus isolates is critical for monitoring MRSA and preventing the spread of VISA or VRSA among patients.

  20. Enzymatic characterization of clinical and environmental Cryptococcus neoformans strains isolated in Italy.

    Science.gov (United States)

    Pini, Gabriella; Faggi, Elisabetta; Campisi, Enza

    Cryptococcus neoformans is an encapsulated yeast causing mainly opportunistic infections. The virulence factors involved in cryptococcosis pathogenesis include the presence and the size of the polysaccharide capsule, the production of melanin by phenoloxidase, the growth at 37°C and the enzyme secretion like proteinase, phospholipase and urease. Many other enzymes are secreted by C. neoformans but their role in the fungus virulence is not yet known. In order to investigate this topic, we compared the phospholipase production between strains from patients and from bird droppings, and we examined its relationship to phenoloxidase production. We further characterized the strains by determining the activity of 19 different extracellular enzymes. Two hundred and five Italian C. neoformans clinical isolates and 32 environmental isolates were tested. Phenoloxidase production was determined by the development of brown colonies on Staib's agar. Extracellular phospholipase activity was performed using the semiquantitative egg-yolk plate method. API ZYM commercial kit was used to observe the production and the activity of 19 different extracellular enzymes. Statistical analysis of the results showed a significantly higher phospholipase activity in the clinical isolates than in the environmental isolates. No significant difference about the phenoloxidase production between both groups was found. Regarding the 19 extracellular enzymes tested using the API ZYM commercial kit, acid phosphatase showed the highest enzymatic activity in both groups. Concerning the enzyme α-glucosidase, the clinical isolates presented a significantly higher positivity percentage than the environmental isolates. A hundred percent positivity in the enzyme leucine arylamidase production was observed in both groups, but the clinical isolates metabolized a significantly greater amount of substrate. The higher phospholipase production in the clinical isolates group confirms the possible role of this

  1. Antibacterial Activity of Rhodomyrtus tomentosa (Aiton Hassk. Leaf Extract against Clinical Isolates of Streptococcus pyogenes

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    Surasak Limsuwan

    2012-01-01

    Full Text Available Ethanol extract of Rhodomyrtus tomentosa (Aiton Hassk. leaf was evaluated for antibacterial activity against 47 clinical isolates of Streptococcus pyogenes. The extract exhibited good anti-S. pyogenes activity against all the tested isolates with similar minimum inhibitory concentration (MIC, 3.91–62.5 μg mL−1 and minimum bactericidal concentration (MBC, 3.91–62.5 μg mL−1 ranges. No surviving cells were detected at 16 h after treatment with 8 × MIC of the extract. The extract-treated cells demonstrated no lysis and cytoplasmic leakage through the bacterial membrane. Electron micrographs further revealed that the extract did not cause any dramatic changes on the treated cells. Rhodomyrtone, an isolated compound, exhibited good anti-S. pyogenes activity (14 isolates, expressed very low MIC (0.39–1.56 μg mL−1 and MBC (0.39-1.56 μg mL−1 values. Rhodomyrtus tomentosa leaf extract and rhodomyrtone displayed promising antibacterial activity against clinical isolates of S. pyogenes.

  2. Comparative analysis and supragenome modeling of twelve Moraxella catarrhalis clinical isolates.

    Science.gov (United States)

    Davie, Jeremiah J; Earl, Josh; de Vries, Stefan P W; Ahmed, Azad; Hu, Fen Z; Bootsma, Hester J; Stol, Kim; Hermans, Peter W M; Wadowsky, Robert M; Ehrlich, Garth D; Hays, John P; Campagnari, Anthony A

    2011-01-26

    M. catarrhalis is a gram-negative, gamma-proteobacterium and an opportunistic human pathogen associated with otitis media (OM) and exacerbations of chronic obstructive pulmonary disease (COPD). With direct and indirect costs for treating these conditions annually exceeding $33 billion in the United States alone, and nearly ubiquitous resistance to beta-lactam antibiotics among M. catarrhalis clinical isolates, a greater understanding of this pathogen's genome and its variability among isolates is needed. The genomic sequences of ten geographically and phenotypically diverse clinical isolates of M. catarrhalis were determined and analyzed together with two publicly available genomes. These twelve genomes were subjected to detailed comparative and predictive analyses aimed at characterizing the supragenome and understanding the metabolic and pathogenic potential of this species. A total of 2383 gene clusters were identified, of which 1755 are core with the remaining 628 clusters unevenly distributed among the twelve isolates. These findings are consistent with the distributed genome hypothesis (DGH), which posits that the species genome possesses a far greater number of genes than any single isolate. Multiple and pair-wise whole genome alignments highlight limited chromosomal re-arrangement. M. catarrhalis gene content and chromosomal organization data, although supportive of the DGH, show modest overall genic diversity. These findings are in stark contrast with the reported heterogeneity of the species as a whole, as wells as to other bacterial pathogens mediating OM and COPD, providing important insight into M. catarrhalis pathogenesis that will aid in the development of novel therapeutic regimens.

  3. Isolation and Antibiogram of Clostridium tetani from Clinically Diagnosed Tetanus Patients.

    Science.gov (United States)

    Hanif, Hajra; Anjum, Awais; Ali, Naeem; Jamal, Asif; Imran, Muhammad; Ahmad, Bashir; Ali, Muhammad Ishtiaq

    2015-10-01

    Clostridium tetani, the etiologic agent of tetanus, produces a toxin that causes spastic paralysis in humans and other vertebrates. This study was aimed for isolation, identification, and determination of antimicrobial susceptibility of C. tetani from clinically diagnosed tetanus patients. Isolation was done from deep-punctured tissues of the foot and arm injuries of 80 clinically diagnosed tetanus patients from the Pakistan Institute of Medical Sciences hospital. We successfully screened out five C. tetani isolates out of 80 samples based on the strain-specific characteristics confirmed through biochemical testing and toxin production. A disc diffusion method was used for antimicrobial susceptibilities and C. tetani isolates showed susceptibility to cefoperazone, chloramphenicol, metronidazole, penicillin G, and tetracycline, but were found to be resistant to erythromycin and ofloxacin. During animal testing, all the infected mice developed symptoms of tetanus. The results showed that identification of C. tetani is possible using biochemical and molecular tools and that the strains of C. tetani isolated had not developed resistance against the antibiotics most often used for the treatment of tetanus. © The American Society of Tropical Medicine and Hygiene.

  4. Application of MALDI-TOF MS for requalification of a Candida clinical isolates culture collection

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    Reginaldo Lima-Neto

    2014-06-01

    Full Text Available Microbial culture collections underpin biotechnology applications and are important resources for clinical microbiology by supplying reference strains and/or performing microbial identifications as a service. Proteomic profiles by MALDI-TOF MS have been used for Candida spp. identification in clinical laboratories and demonstrated to be a fast and reliable technique for the routine identification of pathogenic yeasts. The main aim of this study was to apply MALDI-TOF MS combined with classical phenotypic and molecular approaches to identify Candida clinical isolates preserved from 1 up to 52 years in a Brazilian culture collection and assess its value for the identification of yeasts preserved in this type of collections. Forty Candida spp. clinical isolates were identified by morphological and biochemical analyses. Identifications were also performed by the new proteomic approach based on MALDI-TOF MS. Results demonstrated 15% discordance when compared with morphological and biochemical analyses. Discordant isolates were analysed by ITS sequencing, which confirmed the MALDI-TOF MS identifications and these strains were renamed in the culture collection catalogue. In conclusion, proteomic profiles by MALDI-TOF MS represents a rapid and reliable method for identifying clinical Candida species preserved in culture collections and may present clear benefits when compared with the performance of existing daily routine methods applied at health centres and hospitals.

  5. Neosporosis in Beagle dogs: clinical signs, diagnosis, treatment, isolation and genetic characterization of Neospora caninum.

    Science.gov (United States)

    Dubey, J P; Vianna, M C B; Kwok, O C H; Hill, D E; Miska, K B; Tuo, W; Velmurugan, G V; Conors, M; Jenkins, M C

    2007-11-10

    Clinical neosporosis was diagnosed in a litter of five pups born to a Beagle bitch from Virginia, USA. Four of the pups developed limb weakness starting at 4 weeks of age. The dogs were suspected to have neosporosis based on clinical signs and empirically treated with Clindamycin (75 mg, oral, twice daily, total 150 mg) starting at 9 weeks of age and the dosage was doubled at 13 weeks of age. Antibodies to Neospora caninum were detected in sera of the dam and pups when first tested serologically at the age of 4 months. The owner donated the pup with the worst clinical signs and the dam for research; both dogs were euthanized. Viable N. caninum was isolated in gamma interferon gene knock out (KO) mice and in cell culture from the pup killed at 137 days of age. Tissue cysts, but no tachyzoites, were found in histological sections of brain and muscles. The isolate was also identified as N. caninum by PCR and sequence analysis and designated NC-9. N. caninum was neither isolated by bioassay in KO mice nor found in histological sections of tissues of the bitch. Clinical signs in the remaining three pups improved considerably after a 6-month treatment with Clindamycin; N. caninum antibody titers were still persistent in these pups at 23 months of age. Results indicate that medication with Clindamycin can improve clinical condition but not eliminate N. caninum infection.

  6. Application of MALDI-TOF MS for requalification of a Candida clinical isolates culture collection.

    Science.gov (United States)

    Lima-Neto, Reginaldo; Santos, Cledir; Lima, Nelson; Sampaio, Paula; Pais, Célia; Neves, Rejane P

    2014-01-01

    Microbial culture collections underpin biotechnology applications and are important resources for clinical microbiology by supplying reference strains and/or performing microbial identifications as a service. Proteomic profiles by MALDI-TOF MS have been used for Candida spp. identification in clinical laboratories and demonstrated to be a fast and reliable technique for the routine identification of pathogenic yeasts. The main aim of this study was to apply MALDI-TOF MS combined with classical phenotypic and molecular approaches to identify Candida clinical isolates preserved from 1 up to 52 years in a Brazilian culture collection and assess its value for the identification of yeasts preserved in this type of collections. Forty Candida spp. clinical isolates were identified by morphological and biochemical analyses. Identifications were also performed by the new proteomic approach based on MALDI-TOF MS. Results demonstrated 15% discordance when compared with morphological and biochemical analyses. Discordant isolates were analysed by ITS sequencing, which confirmed the MALDI-TOF MS identifications and these strains were renamed in the culture collection catalogue. In conclusion, proteomic profiles by MALDI-TOF MS represents a rapid and reliable method for identifying clinical Candida species preserved in culture collections and may present clear benefits when compared with the performance of existing daily routine methods applied at health centres and hospitals.

  7. Line probe assay for differentiation within Mycobacterium tuberculosis complex. Evaluation on clinical specimens and isolates including Mycobacterium pinnipedii

    DEFF Research Database (Denmark)

    Kjeldsen, Marianne Kirstine; Bek, Dorte; Rasmussen, Erik Michael

    2009-01-01

    A line probe assay (GenoType MTBC) was evaluated for species differentiation within the Mycobacterium tuberculosis complex (MTBC). We included 387 MTBC isolates, 43 IS6110 low-copy MTBC isolates, 28 clinical specimens with varying microscopy grade, and 30 isolates of non-tuberculous mycobacteria...

  8. Antibacterial activity of mupirocin (pseudomonic Acid A) against, clinical isolates of methicillin-resistant staphylococcus aureus

    International Nuclear Information System (INIS)

    Farooq, M.; Abbasi, S.A.; Butt, T.; Arain, M.A

    2010-01-01

    Colonized patients and health care workers are the main source of spread of methicillin resistant Staphylococcus aureus (MRSA) in hospitals. The elimination of nasal colonized MRSA plays a crucial role in infection control protocols. Mupirocin (pseudomonic acid A) is used for eradication of MRSA nasal carriage. Increasing use of pseudomonic acid A (mupirocin) has led to emergence of resistance. Objective To determine low and high level resistance of MRSA isolates from clinical specimens against mupirocin. Place and duration of study: Study was conducted at Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi from July 2006 to June 2007. Material and methods Three hundred methicillin-resistant Staphylococcus aureus isolates were studied. All clinical specimens were processed for culture and sensitivity. Staphylococcus aureus isolates were tested for methicillin resistance using 1 micro g oxacillin disk. The isolates were further tested by PCR for the presence of mecA gene. Minimum Inhibitory Concentration (MIC) of mupirocin against MRSA isolates was determined using agar dilution technique. Results Out of 300 MRSA isolates, 98% were found to have MlC against mupirocin as smaller than 4 micro g/mL. Remaining 2% isolates revealed low level resistance (MIC greater than 8 micro g/mL to 256 micro g/mL), no high level resistance (MIC greater than 512 micro g/mL) against mupirocin was detected. Conclusions: High level mupirocin resistance has not emerged so far in our setup. Due to increasing use of mupirocin, emergence of resistance against mupirocin among MRSA is a strong possibility. Strategy encompassing rational use of antimicrobials, hospital infection control, surveillance for the detection of mupirocin resistance and judicious use of this agent is required. (author)

  9. Variation of Housekeeping Genes in Clinical Isolates and Vaccine Strains of Bordetella pertussis.

    Science.gov (United States)

    Fathi, Masoumeh; Haghighi, Faezeh; Shahcheraghi, Fereshteh; Abbasi, Ebrahim; Eshraghi, Seyed Saeed; Ghourchian, Sedighe; Zeraati, Hojjat; Yaseri, Mehdi; Douraghi, Masoumeh; Shokri, Fazel

    2017-04-01

    Bordetella pertussis causes serious contagious infections, primarily in childhood. A whole-cell vaccine, diphtheria-tetanus-whole cell pertussis (DTwP), has been used to protect against pertussis in children in Iran, but the pertussis cases have been increasing during recent years. We determined the allelic variation level of housekeeping genes in isolates recovered from pertussis patients and vaccine strains used in national vaccination program. Five clinical isolates, 2 vaccine strains and a Tohama I strain were studied through multilocus sequence typing (MLST) of housekeeping genes. The relatedness between STs, the founder, single- and double-locus variants (SLVs, DLVs) was determined using eBURST algorithm. The concordance between the type assignments by MLST and PFGE was determined. In the 5 clinical isolates, 2 STs were identified, ST2 and ST79. The vaccine strains displayed two distinct allelic profiles assigned to ST1 and ST2. ST2 was predicted as founder and the remaining STs were SLVs of ST2. MLST and PFGE type assignments were 86.6% concordant. The clinical isolates of B. pertussis were different from vaccine strains used in the national vaccination program. This study confirms the low level of variation in housekeeping genes of B. pertussis. MLST of virulent antigenic genes needs to be applied as a complementary method for the characterization of new ST-harboring isolates that may predominate periodically. The combination of these data allows rapid and efficient surveillance of currently circulating isolates. These data might elucidate the future trends and considerations for vaccine formulation and design.

  10. MIC of Delamanid (OPC-67683) against Mycobacterium tuberculosis Clinical Isolates and a Proposed Critical Concentration

    Science.gov (United States)

    Stinson, Kelly; Kurepina, Natalia; Venter, Amour; Fujiwara, Mamoru; Kawasaki, Masanori; Timm, Juliano; Shashkina, Elena; Kreiswirth, Barry N.; Liu, Yongge

    2016-01-01

    The increasing global burden of multidrug-resistant tuberculosis (MDR-TB) requires reliable drug susceptibility testing that accurately characterizes susceptibility and resistance of pathogenic bacteria to effectively treat patients with this deadly disease. Delamanid is an anti-TB agent first approved in the European Union in 2014 for the treatment of pulmonary MDR-TB in adults. Using the agar proportion method, delamanid MIC was determined for 460 isolates: 316 from patients enrolled in a phase 2 global clinical trial, 76 from two phase 2 early bactericidal activity trials conducted in South Africa, and 68 isolates obtained outside clinical trials (45 from Japanese patients and 23 from South African patients). With the exception of two isolates, MICs ranged from 0.001 to 0.05 μg/ml, resulting in an MIC50 of 0.004 μg/ml and an MIC90 of 0.012 μg/ml. Various degrees of resistance to other anti-TB drugs did not affect the distribution of MICs, nor did origin of isolates from regions/countries other than South Africa. A critical concentration/breakpoint of 0.2 μg/ml can be used to define susceptible and resistant isolates based on the distribution of MICs and available pharmacokinetic data. Thus, clinical isolates from delamanid-naive patients with tuberculosis have a very low MIC for delamanid and baseline resistance is rare, demonstrating the potential potency of delamanid and supporting its use in an optimized background treatment regimen for MDR-TB. PMID:26976868

  11. Molecular Identification and Conventional Susceptibility Testing of Iranian Clinical Mycobacterium fortuitum Isolates

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    Parvin Heidarieh

    2010-01-01

    Full Text Available Rapidly growing mycobacteria (RGM are capable of producing diseases in humans. Since mycobacteria vary in their susceptibility, precise identification is critical for adoption of correct drug therapy. The main aim of this study was molecular identification and evaluation of antimicrobial susceptibility pattern of Iranian clinically isolated Myocbacterium fortuitum.Materials and MethodsA total of 72 presumptively identified isolates of clinical atypical mycobacteria collected by Isfahan Research Center for Infectious Diseases & Tropical Medicine during 2006-2008 were included in the current study. A combination of conventional and molecular tests was applied to identify the isolates. Molecular methods including genus and group specific PCR and PCR-Restriction Algorithm (PRA based on hsp65 gene were applied to achieve exact identification of mycobacterial strains. Antimicrobial susceptibility testing on M. fortuitum isolates was performed by in-house prepared broth microdilution test..ResultsOut of 72 collected atypical mycobacteria isolates, we identified 25 strains of M. fortuitum. All strains had the specific molecular markers of mycobacterial identity and similar species specific PRA pattern of the international type strain of M. fortuitum. Drug susceptibility testing showed that the M. fortuitum isolates are sensitive to amikacin, sulfamethoxazole and ciprofloxacin (100%, imipenem (92%, clarithromycin (76%, cefoxitin (56% and doxycycline (16%.ConclusionMolecular identification of atypical mycobacteria based on PRA is a reliable and rapid approach which can identify mycobacterial strains to the species level. Our study showed that M. fortuitum plays a significant role in pulmonary and extrapulmonary infection in patients and should be given proper considerations when clinical samples are processed.

  12. Exploring the contribution of efflux on the resistance to fluoroquinolones in clinical isolates of Staphylococcus aureus

    LENUS (Irish Health Repository)

    Costa, Sofia SANTOS

    2011-10-27

    Abstract Background Antimicrobial resistance mediated by efflux systems is still poorly characterized in Staphylococcus aureus, despite the description of several efflux pumps (EPs) for this bacterium. In this work we used several methodologies to characterize the efflux activity of 52 S. aureus isolates resistant to ciprofloxacin collected in a hospital in Lisbon, Portugal, in order to understand the role played by these systems in the resistance to fluoroquinolones. Results Augmented efflux activity was detected in 12 out of 52 isolates and correlated with increased resistance to fluoroquinolones. Addition of efflux inhibitors did not result in the full reversion of the fluoroquinolone resistance phenotype, yet it implied a significant decrease in the resistance levels, regardless of the type(s) of mutation(s) found in the quinolone-resistance determining region of grlA and gyrA genes, which accounted for the remaining resistance that was not efflux-mediated. Expression analysis of the genes coding for the main efflux pumps revealed increased expression only in the presence of inducing agents. Moreover, it showed that not only different substrates can trigger expression of different EP genes, but also that the same substrate can promote a variable response, according to its concentration. We also found isolates belonging to the same clonal type that showed different responses towards drug exposure, thus evidencing that highly related clinical isolates may diverge in the efflux-mediated response to noxious agents. The data gathered by real-time fluorometric and RT-qPCR assays suggest that S. aureus clinical isolates may be primed to efflux antimicrobial compounds. Conclusions The results obtained in this work do not exclude the importance of mutations in resistance to fluoroquinolones in S. aureus, yet they underline the contribution of efflux systems for the emergence of high-level resistance. All together, the results presented in this study show the potential

  13. Antifungal activity of linalool in cases of Candida spp. isolated from individuals with oral candidiasis

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    I. J. Dias

    2017-09-01

    Full Text Available Abstract This study analyzed the antifungal activity of phytoconstituents from linalool on Candida spp. strains, in vitro, isolated from patients with clinical diagnoses of oral candidiasis associated with the use of a dental prosthesis. Biological samples were collected from 12 patients using complete dentures or removable partial dentures and who presented mucous with diffuse erythematous or stippled features, indicating a clinical diagnosis of candidiasis. To identify fungal colonies of the genus Candida, samples were plated onto CHROMagar Candida®. The antifungal activity of linalool, a monoterpene unsaturated constituent of basil oil, was performed using the broth microdilution technique. Then, the minimum inhibitory concentration (MIC, the two subsequent stronger concentrations and the positive controls were subcultured on Sabouraud Dextrose Agar plates to determine the minimum fungicidal concentration (MFC. The experiments were performed in triplicate and nystatin was used as a positive control in all tests. Diagnoses of oral candidiasis were verified in eight patients (66.6% and the most prevalent fungal species was Candida albicans (37.5%, followed by Candida krusei (25.0%; and Candida tropicalis (4.2%. The best antifungal activity of linalool was observed on Candida tropicalis (MIC = 500 mg/mL, followed by Candida albicans (MIC = 1.000 mg/mL, and Candida krusei (MIC = 2.000 mg/mL.Under the study conditions and based on the results obtained, it can be concluded that the Candida strains tested were susceptible to linalool.

  14. Antimicrobial resistance levels amongst staphylococci isolated from clinical cases of bovine mastitis in Kosovo.

    Science.gov (United States)

    Mehmeti, Ibrahim; Behluli, Behlul; Mestani, Mergim; Ademi, Arsim; Nes, Ingolf F; Diep, Dzung B

    2016-10-31

    Mastitis is one of the most frequent and costly disease in cattle. We studied milk samples from cattle with mastitis from farms in Kosovo to identify mastitis-causing pathogens and possible effective antibiotics. Our ultimate goal is to help implement adequate antibiotic management and treatment practices in Kosovo METHODOLOGY: A total of 152 milk samples were collected from cows with clinical mastitis from different farms in Kosovo. After identification of microorganisms, antibiotic susceptibility and the occurrence of enterotoxins was investigated. Staphylococci were found in 89 samples, of which 58 were coagulase negative and 31 coagulase positive. S. aureus was isolated from 27 samples, S. epidermidis from 25, and S. chromogenes from 15, while other species of staphylococci were isolated from the remaining 22 isolates. Interestingly, the bacterial diversity was different between cows in different periods of lactation and among different breeds. Most of the isolates (76/89) were resistant to two or more antibiotics. The highest resistance was to penicillin and ampicillin (> 65%), followed by tetracycline, oxacillin, streptomycin, chloramphenicol (> 23%), and less than 3% to erythromycin. Of the 89 isolates, 40 produced enterotoxins that were most frequently typed as A and C. We detected human bacterial pathogens in the cultures of milk samples from cows with mastitis. The isolates demonstrated resistance to two or more antibiotics, some of which are frequently used to treat animal and human infections. We recommend increased control and more stringent use of antibiotics in veterinary as well as human medicine.

  15. Surgical and Clinical Decision Making in Isolated Long Thoracic Nerve Palsy.

    Science.gov (United States)

    Noland, Shelley S; Krauss, Emily M; Felder, John M; Mackinnon, Susan E

    2017-10-01

    Isolated long thoracic nerve palsy results in scapular winging and destabilization. In this study, we review the surgical management of isolated long thoracic nerve palsy and suggest a surgical technique and treatment algorithm to simplify management. In total, 19 patients who required surgery for an isolated long thoracic nerve palsy were reviewed retrospectively. Preoperative demographics, electromyography (EMG), and physical examinations were reviewed. Intraoperative nerve stimulation, surgical decision making, and postoperative outcomes were reviewed. In total, 19 patients with an average age of 32 were included in the study. All patients had an isolated long thoracic nerve palsy caused by either an injury (58%), Parsonage-Turner syndrome (32%), or shoulder surgery (10%); 18 patients (95%) underwent preoperative EMG; 10 with evidence of denervation (56%); and 13 patients had motor unit potentials in the serratus anterior (72%). The preoperative EMG did not correlate with intraoperative nerve stimulation in 13 patients (72%) and did correlate in 5 patients (28%); 3 patients had a nerve transfer (3 thoracodorsal to long thoracic at lateral chest, 1 pec to long thoracic at supraclavicular incision). In the 3 patients who had a nerve transfer, there was return of full forward flexion of the shoulder at an average of 2.5 months. A treatment algorithm based on intraoperative nerve stimulation will help guide surgeons in their clinical decision making in patients with isolated long thoracic nerve palsy. Intraoperative nerve stimulation is the gold standard in the management of isolated long thoracic nerve palsy.

  16. Phylogenetic relationships among Staphylococcus aureus isolated from clinical samples in Mashhad, Iran.

    Science.gov (United States)

    Khademi, Farzad; Ghanbari, Fahimeh; Mellmann, Alexander; Najafzadeh, Mohammad J; Khaledi, Azad

    2016-01-01

    The spa gene occurs in all strains of Staphylococcus aureus (S. aureus), can function as a genetic marker and might be used distinguish strains at the species level. Hence, due to these advantages, we used spa typing and the Based Upon Repeat Pattern (BURP) to assign the clonal and phylogenetic relationships of S. aureus strains. The sensitivity of S. aureus strains to methicillin was determined using agar disk diffusion. The extracted DNA from 56 isolates of S. aureus was subjected to PCR to detect the spa gene with specific primers. The spa typing method was performed for each of the isolates, and then, BURP was used to cluster spa types (spa-CCs). Finally, using relevant software, the phylogenic tree was drawn. The results of this study showed that 25 out of 56 (44.6%) isolates were resistant to methicillin. The typing of S. aureus isolates revealed 24 different spa types among 56 isolates, and BURP analysis clustered the 24 spa types into 5 spa clonal complexes (CCs) and 12 singletons. The process of spa typing, in combination with BURP analysis, provides an efficient method for investigating phylogenetic and clonal relationships among clinical isolates and can be useful for monitoring bacterial spread between hospitals and communities as well as between and within hospitals. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  17. Determination of antifungal susceptibility patterns among the clinical isolates of Candida species

    Directory of Open Access Journals (Sweden)

    Kamiar Zomorodian

    2011-01-01

    Full Text Available Context: Candida species are opportunistic yeasts that cause infections ranging from simple dermatosis to potentially life-threatening fungemia. The emergence of resistance to antifungal drugs has been increased in the past two decades. Aim: the present study we determined to find out the susceptibility profiles of clinical isolates of Candida species against four antifungal drugs, including amphotericin B, ketoconazole, fluconazole and itraconazole. Materials and Methods: Antifungal susceptibility testing of the yeasts was done in accordance with the proposed guidelines for antifungal disk diffusion susceptibility testing of yeasts based on the CLSI document M44-A. Results: A total of 206 yeast isolates were assessed. Among the evaluated Candida species, the highest rates of resistance to ketoconazole were seen in Candida glabrata (16.6% and Candida albicans (3.2%. Susceptibility and intermediate response to fluconazole were seen in 96.6% and 3.4% of the Candida isolates, respectively. A total of 19 (9.2% yeast isolates showed petite phenomenon including 11 C. glabrata, 3 C. albicans, 2 Candida dubliniensis and one isolate of each Candida krusei and Candida parapsilosis. Conclusion: The high number of petite mutation in the isolated yeasts should be seriously considered since it may be one of the reasons of antifungal treatment failure.

  18. Antimicrobial resistance, virulence, and phylogenetic characteristics of Escherichia coli isolates from clinically healthy swine.

    Science.gov (United States)

    Lay, Khin Khin; Koowattananukul, Chailai; Chansong, Nisit; Chuanchuen, Rungtip

    2012-11-01

    A total of 344 commensal Escherichia coli isolates from clinically healthy pigs were examined for antimicrobial resistance phenotypes, class 1 integrons, resistance genes, virulence gene profile, and phylogenetic groups. The majority of E. coli isolates were resistant to tetracycline (96.2%) and ampicillin (91.6%). Up to 98% were multidrug resistant. Seventy-three percent of the isolates carried class 1 integrons. Inserted-gene cassette arrays in variable regions included incomplete sat, aadA22, aadA1, dfrA12-aadA2, and sat-psp-aadA2, of which the aadA2 gene cassette was most prevalent (42.9%). Horizontal transfer was detected in eight E. coli isolates carrying class 1 integrons with dfrA12-aadA2 gene cassette array. Sixteen resistance genes were identified among the E. coli isolates with corresponding resistance phenotype. Ten virulence genes (including elt, estA, estB, astA, faeG, fasA, fedA, eaeA, paa, and sepA) were detected, of which fasA was most commonly found (98.3%). Most of the E. coli isolates belonged to phylogenetic group B1. Significantly positive associations were observed between some virulence genes and some resistance phenotypes and genotypes (p antimicrobial resistance-encoding genes and virulence determinants.

  19. Route of infection alters virulence of neonatal septicemia Escherichia coli clinical isolates

    Science.gov (United States)

    Cole, Bryan K.; Scott, Edgar; Ilikj, Marko; Bard, David; Akins, Darrin R.; Dyer, David W.

    2017-01-01

    Escherichia coli is the leading cause of Gram-negative neonatal septicemia in the United States. Invasion and passage across the neonatal gut after ingestion of maternal E. coli strains produce bacteremia. In this study, we compared the virulence properties of the neonatal E. coli bacteremia clinical isolate SCB34 with the archetypal neonatal E. coli meningitis strain RS218. Whole-genome sequencing data was used to compare the protein coding sequences among these clinical isolates and 33 other representative E. coli strains. Oral inoculation of newborn animals with either strain produced septicemia, whereas intraperitoneal injection caused septicemia only in pups infected with RS218 but not in those injected with SCB34. In addition to being virulent only through the oral route, SCB34 demonstrated significantly greater invasion and transcytosis of polarized intestinal epithelial cells in vitro as compared to RS218. Protein coding sequences comparisons highlighted the presence of known virulence factors that are shared among several of these isolates, and revealed the existence of proteins exclusively encoded in SCB34, many of which remain uncharacterized. Our study demonstrates that oral acquisition is crucial for the virulence properties of the neonatal bacteremia clinical isolate SCB34. This characteristic, along with its enhanced ability to invade and transcytose intestinal epithelium are likely determined by the specific virulence factors that predominate in this strain. PMID:29236742

  20. A Secreted Ankyrin-Repeat Protein from Clinical Stenotrophomonas maltophilia Isolates Disrupts Actin Cytoskeletal Structure.

    Science.gov (United States)

    MacDonald, Logan C; O'Keefe, Sean; Parnes, Mei-Fan; MacDonald, Hanlon; Stretz, Lindsey; Templer, Suzanne J; Wong, Emily L; Berger, Bryan W

    2016-01-08

    Stenotrophomonas maltophilia is an emerging, multidrug-resistant pathogen of increasing importance for the immunocompromised, including cystic fibrosis patients. Despite its significance as an emerging pathogen, relatively little is known regarding the specific factors and mechanisms that contribute to its pathogenicity. We identify and characterize a putative ankyrin-repeat protein (Smlt3054) unique to clinical S. maltophilia isolates that binds F-actin in vitro and co-localizes with actin in transfected HEK293a cells. Smlt3054 is endogenously expressed and secreted from clinical S. maltophilia isolates, but not an environmental isolate (R551-3). The in vitro binding of Smlt3054 to F-actin resulted in a thickening of the filaments as observed by TEM. Ectopic expression of Smlt3054-GFP exhibits strong co-localization with F-actin, with distinct, retrograde F-actin waves specifically associated with Smlt3054 in individual cells as well as formation of dense, internal inclusions at the expense of retrograde F-actin waves. Collectively, our results point to an interaction between Smlt3054 and F-actin. Furthermore, as a potentially secreted protein unique to clinical S. maltophilia isolates, Smlt3054 may serve as a starting point for understanding the mechanisms by which S. maltophilia has become an emergent pathogen.

  1. Microbiological and biochemical studies on certain antibiotic-resistant bacteria isolated from certain clinical specimens

    International Nuclear Information System (INIS)

    Nada, H.M.AL.M.

    2008-01-01

    Infection is a dynamic process involving invasion of the body by pathogenic microorganisms and reactions of the tissues to microorganisms and their toxins. Pathogenic microorganisms isolated from clinical samples are of great threat to human health.The outcome of an infection depends on the virulence of the pathogen and the relative degree of resistance or susceptibility to antimicrobial chemotherapy. Antimicrobial agents interfere with specific processes that are essential for growth and division.Development of antibiotic resistance in bacteria is a problem of great concern. The high prevalence of resistant bacteria seems to be related to uncontrolled usage of antibiotics. B-lactamases are the most common cause of bacterial resistance to B-lactam antimicrobial agents, and it is one of the most important reason for increasing the resistance in pathogenic bacteria against some antibiotics especially those acting on inhibition of cell wall synthesis. One hundred and seven clinical samples and specimens were collected from public, private hospitals and National Cancer Institute (NCI) in Cairo, Egypt. Out of them 72 cases positive for microbial infection. Twelve cases were showed mixed infection. Eighty four isolates of pathogenic bacteria and yeast were collected from single and mixed culture. Susceptibilities of the isolates to 20 different antimicrobial agents were determined according to Kirby-Bauer method. Nine multi-drug resistant gram-negative bacterial strains were identified by (Micro Scan WalkAway 96 SI System). Six of them urine isolates, 2 wound (pus) isolates and one sputum isolate. The identified strains were exposed to in-vitro gamma irradiation at dose level of 24.4 Gy, which is biologically equivalent to the fractionated multiple therapeutic dose used in the protocol of cancer treatment of some patients. The antimicrobial susceptibility of the nine multi-drug resistant strains were carried out by disk diffusion method before and after irradiation

  2. Molecular characterization of fluoroquinolone resistance in nontypeable Haemophilus influenzae clinical isolates.

    Science.gov (United States)

    Puig, Carmen; Tirado-Vélez, José Manuel; Calatayud, Laura; Tubau, Fe; Garmendia, Junkal; Ardanuy, Carmen; Marti, Sara; de la Campa, Adela G; Liñares, Josefina

    2015-01-01

    Nontypeable Haemophilus influenzae (NTHi) is a common cause of respiratory infections in adults, who are frequently treated with fluoroquinolones. The aims of this study were to characterize the genotypes of fluoroquinolone-resistant NTHi isolates and their mechanisms of resistance. Among 7,267 H. influenzae isolates collected from adult patients from 2000 to 2013, 28 (0.39%) were ciprofloxacin resistant according to Clinical and Laboratory Standards Institute (CLSI) criteria. In addition, a nalidixic acid screening during 2010 to 2013 detected five (0.23%) isolates that were ciprofloxacin susceptible but nalidixic acid resistant. Sequencing of their quinolone resistance-determining regions and genotyping by pulse-field gel electrophoresis and multilocus sequence typing of the 25 ciprofloxacin-resistant isolates available and all 5 nalidixic acid-resistant isolates were performed. In the NTHi isolates studied, two mutations producing changes in two GyrA residues (Ser84, Asp88) and/or two ParC residues (Ser84, Glu88) were associated with increased fluoroquinolone MICs. Strains with one or two mutations (n = 15) had ciprofloxacin and levofloxacin MICs of 0.12 to 2 μg/ml, while those with three or more mutations (n = 15) had MICs of 4 to 16 μg/ml. Long persistence of fluoroquinolone-resistant strains was observed in three chronic obstructive pulmonary disease patients. High genetic diversity was observed among fluoroquinolone-resistant NTHi isolates. Although fluoroquinolones are commonly used to treat respiratory infections, the proportion of resistant NTHi isolates remains low. The nalidixic acid disk test is useful for detecting the first changes in GyrA or in GyrA plus ParC among fluoroquinolone-susceptible strains that are at a potential risk for the development of resistance under selective pressure by fluoroquinolone treatment. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Molecular Characterization of Fluoroquinolone Resistance in Nontypeable Haemophilus influenzae Clinical Isolates

    Science.gov (United States)

    Puig, Carmen; Tirado-Vélez, José Manuel; Calatayud, Laura; Tubau, Fe; Garmendia, Junkal; Ardanuy, Carmen; Marti, Sara

    2014-01-01

    Nontypeable Haemophilus influenzae (NTHi) is a common cause of respiratory infections in adults, who are frequently treated with fluoroquinolones. The aims of this study were to characterize the genotypes of fluoroquinolone-resistant NTHi isolates and their mechanisms of resistance. Among 7,267 H. influenzae isolates collected from adult patients from 2000 to 2013, 28 (0.39%) were ciprofloxacin resistant according to Clinical and Laboratory Standards Institute (CLSI) criteria. In addition, a nalidixic acid screening during 2010 to 2013 detected five (0.23%) isolates that were ciprofloxacin susceptible but nalidixic acid resistant. Sequencing of their quinolone resistance-determining regions and genotyping by pulse-field gel electrophoresis and multilocus sequence typing of the 25 ciprofloxacin-resistant isolates available and all 5 nalidixic acid-resistant isolates were performed. In the NTHi isolates studied, two mutations producing changes in two GyrA residues (Ser84, Asp88) and/or two ParC residues (Ser84, Glu88) were associated with increased fluoroquinolone MICs. Strains with one or two mutations (n = 15) had ciprofloxacin and levofloxacin MICs of 0.12 to 2 μg/ml, while those with three or more mutations (n = 15) had MICs of 4 to 16 μg/ml. Long persistence of fluoroquinolone-resistant strains was observed in three chronic obstructive pulmonary disease patients. High genetic diversity was observed among fluoroquinolone-resistant NTHi isolates. Although fluoroquinolones are commonly used to treat respiratory infections, the proportion of resistant NTHi isolates remains low. The nalidixic acid disk test is useful for detecting the first changes in GyrA or in GyrA plus ParC among fluoroquinolone-susceptible strains that are at a potential risk for the development of resistance under selective pressure by fluoroquinolone treatment. PMID:25385097

  4. Unprecedented Silver Resistance in Clinically Isolated Enterobacteriaceae: Major Implications for Burn and Wound Management.

    Science.gov (United States)

    Finley, Phillip J; Norton, Rhy; Austin, Cindy; Mitchell, Amber; Zank, Sara; Durham, Paul

    2015-08-01

    Increased utilization of inorganic silver as an adjunctive to many medical devices has raised concerns of emergent silver resistance in clinical bacteria. Although the molecular basis for silver resistance has been previously characterized, to date, significant phenotypic expression of these genes in clinical settings is yet to be observed. Here, we identified the first strains of clinical bacteria expressing silver resistance at a level that could significantly impact wound care and the use of silver-based dressings. Screening of 859 clinical isolates confirmed 31 harbored at least 1 silver resistance gene. Despite the presence of these genes, MIC testing revealed most of the bacteria displayed little or no increase in resistance to ionic silver (200 to 300 μM Ag(+)). However, 2 isolates (Klebsiella pneumonia and Enterobacter cloacae) were capable of robust growth at exceedingly high silver concentrations, with MIC values reaching 5,500 μM Ag(+). DNA sequencing of these two strains revealed the presence of genes homologous to known genetic determinants of heavy metal resistance. Darkening of the bacteria's pigment was observed after exposure to high silver concentrations. Scanning electron microscopy images showed the presence of silver nanoparticles embedded in the extracellular polymeric substance of both isolates. This finding suggested that the isolates may neutralize ionic silver via reduction to elemental silver. Antimicrobial testing revealed both organisms to be completely resistant to many commercially available silver-impregnated burn and wound dressings. Taken together, these findings provide the first evidence of clinical bacteria capable of expressing silver resistance at levels that could significantly impact wound management. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  5. Unprecedented Silver Resistance in Clinically Isolated Enterobacteriaceae: Major Implications for Burn and Wound Management

    Science.gov (United States)

    Norton, Rhy; Austin, Cindy; Mitchell, Amber; Zank, Sara; Durham, Paul

    2015-01-01

    Increased utilization of inorganic silver as an adjunctive to many medical devices has raised concerns of emergent silver resistance in clinical bacteria. Although the molecular basis for silver resistance has been previously characterized, to date, significant phenotypic expression of these genes in clinical settings is yet to be observed. Here, we identified the first strains of clinical bacteria expressing silver resistance at a level that could significantly impact wound care and the use of silver-based dressings. Screening of 859 clinical isolates confirmed 31 harbored at least 1 silver resistance gene. Despite the presence of these genes, MIC testing revealed most of the bacteria displayed little or no increase in resistance to ionic silver (200 to 300 μM Ag+). However, 2 isolates (Klebsiella pneumonia and Enterobacter cloacae) were capable of robust growth at exceedingly high silver concentrations, with MIC values reaching 5,500 μM Ag+. DNA sequencing of these two strains revealed the presence of genes homologous to known genetic determinants of heavy metal resistance. Darkening of the bacteria's pigment was observed after exposure to high silver concentrations. Scanning electron microscopy images showed the presence of silver nanoparticles embedded in the extracellular polymeric substance of both isolates. This finding suggested that the isolates may neutralize ionic silver via reduction to elemental silver. Antimicrobial testing revealed both organisms to be completely resistant to many commercially available silver-impregnated burn and wound dressings. Taken together, these findings provide the first evidence of clinical bacteria capable of expressing silver resistance at levels that could significantly impact wound management. PMID:26014954

  6. Biofilm-Forming Potential of Staphylococcus aureus Isolated from Clinical Mastitis Cases in New Zealand.

    Science.gov (United States)

    Notcovich, Shirli; DeNicolo, Gina; Flint, Steve H; Williamson, Norman B; Gedye, Kristene; Grinberg, Alex; Lopez-Villalobos, Nicolas

    2018-01-19

    Biofilm formation is of growing concern in human and animal health. However, it is still unclear how biofilms are related to mastitis infections in dairy cattle. In this study, a comparison between two tests for biofilm formation and the association between biofilm and the presence of genes associated with biofilm formation were investigated for 92 Staphylococcus aureus isolates from clinical mastitis cases. Congo red agar (CRA) and microtitre test assay (MTA) in vitro phenotypic tests were used to evaluate biofilm formation. The presence of icaA , icaD , and bap genes associated with biofilm formation was confirmed using the polymerase chain reaction. Results show that most of the S. aureus isolates, though not possessing one of the biofilm-forming genes, were able to produce biofilms. MTA was more frequently positive in identifying biofilm-forming isolates than CRA.

  7. Clinical information on admission is insufficient to determine the appropriate isolation regimen for acute gastroenteritis

    DEFF Research Database (Denmark)

    Skyum, Florence; Abed, Osama Karim; Backer Mogensen, Christian

    2014-01-01

    admitted acutely within a one-year study period to a Danish hospital with a catchment population of 231,000 persons. The following items were analysed: information from the referring doctor, diarrhoea, nausea and vomiting and fever history, abdominal pain, prior antibiotics, co-morbidity, drugs, travel...... admitted patients and to analyse their clinical information focusing on risk indicators of contagious aetiology and on the chosen isolation regime to determine if the GE required a contact precaution isolation regime. MATERIAL AND METHODS: This study included patients above 16 years of age who were...... history, contagious contacts, general condition, vital values, isolation regime, final diagnosis and results of stool examination. RESULTS: Among 17,531 acute admissions, 1.6% had acute GE and 60% of these had stool examinations performed. Only 35% of the patients with GE had information about possible GE...

  8. Identification of a novel clone, ST736, among Enterococcus faecium clinical isolates and its association with daptomycin nonsusceptibility.

    Science.gov (United States)

    Wang, Guiqing; Kamalakaran, Sitharthan; Dhand, Abhay; Huang, Weihua; Ojaimi, Caroline; Zhuge, Jian; Yee, Leslie Lee; Mayigowda, Pramod; Surendraiah, Pavan Kumar Makam; Dimitrova, Nevenka; Fallon, John T

    2014-08-01

    Resistance to daptomycin in enterococcal clinical isolates remains rare but is being increasingly reported in the United States and worldwide. There are limited data on the genetic relatedness and microbiological and clinical characteristics of daptomycin-nonsusceptible enterococcal clinical isolates. In this study, we assessed the population genetics of daptomycin-nonsusceptible Enterococcus faecium (DNSE) clinical isolates by multilocus sequence typing (MLST) and whole-genome sequencing analysis. Forty-two nonduplicate DNSE isolates and 43 randomly selected daptomycin-susceptible E. faecium isolates were included in the analysis. All E. faecium isolates were recovered from patients at a tertiary care medical center in suburban New York City from May 2009 through December 2013. The daptomycin MICs of the DNSE isolates ranged from 6 to >256 μg/ml. Three major clones of E. faecium (ST18, ST412, and ST736) were identified among these clinical isolates by MLST and whole-genome sequence-based analysis. A newly recognized clone, ST736, was seen in 32 of 42 (76.2%) DNSE isolates and in only 14 of 43 (32.6%) daptomycin-susceptible E. faecium isolates (P clone ST736 and daptomycin nonsusceptibility. The identification and potential spread of this novel E. faecium clone and its association with daptomycin nonsusceptibility constitute a challenge for patient management and infection control at our medical center. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  9. Nationwide surveillance of resistance rates of Staphylococcus aureus clinical isolates from Greek hospitals, 2012-2013.

    Science.gov (United States)

    Souli, Maria; Karaiskos, Ilias; Galani, Lambrini; Maraki, Sofia; Perivolioti, Efstathia; Argyropoulou, Athina; Charissiadou, Athina; Zachariadou, Levantia; Tsiplakou, Sofia; Papaioannou, Vassiliki; Tsorlini, Helen; Katsifa, Helen; Baka, Vasiliki; Pantazi, Paraskevi; Paschali, Angeliki; Kyratsa, Anna; Trikka-Graphakos, Eleftheria; Giannopoulou, Panagiota; Vogiatzakis, Evangelos; Moraitou, Helen; Papadogeorgaki, Helen; Avgerinou, Helen; Panagea, Theofano; Pantazatou, Angeliki; Petinaki, Efthymia; Stamatopoulou, Giannoula; Toutouza, Marina; Karatzoglou, Ioanna; Kontopoulou, Konstantina; Orfanidou, Maria; Karantani, Irene; Fytas, Panteleimon; Tzanetou, Konstantina; Platsouka, Evangelia; Kazila, Polyzo; Chli, Anastasia; Statiri, Ntina; Giamarellou, Helen

    2016-04-01

    Purpose To evaluate the in vitro efficacy of several anti-staphylococcal agents against a nationwide collection of contemporary Staphylococcus aureus clinical isolates from several healthcare centres in Greece. Methods Thirty hospitals throughout Greece (18 in Attica) provided all clinical isolates of S.aureus from April 2012 to May 2013 to a central lab to be re-submitted to susceptibility testing. The MICs were evaluated by Vitek® 2 with the exception of ceftaroline (OXOID M.I.C. Evaluator™). Vancomycin and daptomycin MICs were also evaluated by Etest®. Heterogeneously vancomycin-intermediate strains (hVISA) were detected by the Etest® GRD. VISA phenotype was confirmed by PAP-AUC. Results A total of 1005 isolates (39% MRSA) were studied. Susceptibility rates were: erythromycin 66.5%, clindamycin 79.2%, SXT 98.9%, rifampicin 97.3%, fusidic acid 67%, moxifloxacin 78.8%, vancomycin 99.9%, ceftaroline 92.9% and linezolid, tigecycline and daptomycin 100%. For mupirocin, high level resistance could be excluded for 98.9% of isolates. Vancomycin Etest® MIC 50/90 were 1.5/1.5 mg/L, 58.5% of isolates exhibited a MIC > 1 and 8.7% a MIC of 2 mg/L, while Vitek® MIC 50/90 were 1/1 and 3.1% showed MIC > 1 mg/L. One VISA strain was detected. Among the selected 175 isolates that were screened for hVISA phenotype, six (3.4%) were positive. In 315 bloodstream isolates, 64.1% had a vancomycin Etest® MIC > 1 mg/L. Conclusions This multi-centre surveillance study revealed that a significant percentage of contemporary S.aureus isolates from Greek patients have a vancomycin MIC (> 1 mg/L) that may compromise the clinical efficacy of the drug for the treatment of serious infections. The in vitro activity of SXT, rifampicin, mupirocin, linezolid, tigecycline, daptomycin and ceftaroline remains excellent.

  10. Characterizing clinical isolates of Acanthamoeba castellanii with high resistance to polyhexamethylene biguanide in Taiwan.

    Science.gov (United States)

    Huang, Fu-Chin; Shih, Min-Hsiu; Chang, Kai-Fei; Huang, Jian-Ming; Shin, Jyh-Wei; Lin, Wei-Chen

    2017-10-01

    Acanthamoeba keratitis (AK), a painful infectious corneal disease, is caused by the free-living pathogenic species Acanthamoeba. The symptoms include corneal infiltrate, epithelial, and stromal destruction, and loss of vision. Current treatment generally involves an hourly application of polyhexamethylene biguanide (PHMB) over a period of several days; however, even this is not entirely effective against all strains/isolates. The aims of this study were to confirm the existence of pathogenic strains in Taiwan which are highly resistant to drugs and to characterize the behavior of these strains. An in vitro Acanthamoeba species culture platform was established to observe the effectiveness of treatment and chart the morphological changes that occur under the effects of drugs using a light microscope and time-lapse recording. Changes in gene expression were examined using reverse transcription polymerase chain reaction (RT-PCR) and real-time PCR. Over 90% of the standard strain cells (ATCC 30010) were lysed after being treated with PHMB for 1 hour; however, clinical isolates of Acanthamoeba castellanii that differed in their susceptibility to the treatment drug were only partly lysed. Following treatment with PHMB, National Cheng Kung University Hospital isolation B (NCKH_B) transformed into a pseudocyst under the effects of drug stress; however, National Cheng Kung University Hospital isolation D (NCKH_D), an isolate with higher tolerance for PHMB, did not transform. Our results confirm the existence of clinical isolates of A. castellanii with high resistance to PHMB in Taiwan and present the alternative drug tolerance of A. castellanii in addition to the transformation of pseudocyst/cyst. Copyright © 2015. Published by Elsevier B.V.

  11. Spores of Clostridium difficile clinical isolates display a diverse germination response to bile salts.

    Directory of Open Access Journals (Sweden)

    Daniela Heeg

    Full Text Available Clostridium difficile spores play a pivotal role in the transmission of infectious diarrhoea, but in order to cause disease spores must complete germination and return to vegetative cell growth. While the mechanisms of spore germination are well understood in Bacillus, knowledge of C. difficile germination remains limited. Previous studies have shown that bile salts and amino acids play an important role in regulating the germination response of C. difficile spores. Taurocholate, in combination with glycine, can stimulate germination, whereas chenodeoxycholate has been shown to inhibit spore germination in a C. difficile clinical isolate. Our recent studies of C. difficile sporulation characteristics have since pointed to substantial diversity among different clinical isolates. Consequently, in this study we investigated how the germination characteristics of different C. difficile isolates vary in response to bile salts. By analysing 29 isolates, including 16 belonging to the BI/NAP1/027 type, we show that considerable diversity exists in both the rate and extent of C. difficile germination in response to rich medium containing both taurocholate and glycine. Strikingly, we also show that although a potent inhibitor of germination for some isolates, chenodeoxycholate does not inhibit the germination, or outgrowth, of all C. difficile strains. Finally, we provide evidence that components of rich media may induce the germination of C. difficile spores, even in the absence of taurocholate. Taken together, these data suggest that the mechanisms of C. difficile spore germination in response to bile salts are complex and require further study. Furthermore, we stress the importance of studying multiple isolates in the future when analysing the nutrients or chemicals that either stimulate or inhibit C. difficile spore germination.

  12. Efficacy of amikacin and ciprofloxacin against clinical isolates of mycobacterium tuberculosis

    International Nuclear Information System (INIS)

    Satti, M.; Faqir, F.; Sattar, A.; Abbasi, S.; Butt, T.; Karamat, K.A.; Abidi, M.

    2010-01-01

    Background: Tuberculosis was a leading cause of death at the turn of the 20 century and continues to be one of the medical scourges of mankind. Before the availability of antimicrobial drugs the cornerstone of treatment was rest in the open air in sanatoria. The major breakthrough in treatment of tuberculosis came with the discovery of Streptomycin. Later, INH, Ethambutol, Pyrazinamide, Rifampicin were added to the arsenal. Objective of this study was to determine the sensitivity of clinical isolates of Mycobacterium tuberculosis against two second-line anti-tuberculosis drugs, Amikacin and Ciprofloxacin. Methods: This cross-sectional study was conducted at Department of Microbiology, Armed Forces Institute of Pathology (AFIP) Rawalpindi. All routine clinical samples received for acid fast bacilli (AFB) in the Department of Microbiology, AFIP, Rawalpindi were processed by modified Petroff's technique and inoculated on Lowenstein Jensen (LJ) medium and Bactec 460 Mycobacterium tuberculosis culture system. After identification of M. tuberculosis sensitivity was performed against first-line anti-tuberculosis drugs. Then susceptibility of M. tuberculosis isolates against Amikacin and Ciprofloxacin was performed on LJ medium. H37Rv was used as control strain. Results: Results were interpreted using resistance ratio method. Out of 100 M. tuberculosis isolates, 98% were sensitive to Amikacin and 97% to Ciprofloxacin. Conclusion: Amikacin and Ciprofloxacin are very effective second line anti-tuberculosis drugs against tuberculosis isolates in our set-up. (author)

  13. Synergistic effects of ethnomedicinal plants of Apocynaceae family and antibiotics against clinical isolates of Acinetobacter baumannii.

    Science.gov (United States)

    Chusri, Sasitorn; Siriyong, Thanyaluck; Na-Phatthalung, Pinanong; Voravuthikunchai, Supayang Piyawan

    2014-06-01

    To investigate the efficacy of 17 ethnomedicinal plants belonging to Apocynaceae family used in combination with 16 conventional antibiotics against non-multidrug resistant-, multidrug resistant (MDR)-, and extensive drug resistant (XDR) Acinetobacter baumannii (A. baumannii). Antibacterial activity and resistance modifying ability of 272 combinations were determined by growth inhibition assays and further confirmed by time-kill assay. Among the combinations of the antibiotics with Apocynaceae ethanol extracts on this pathogen, 15 (5%) had synergistic effects, 23 (8%) had partial synergistic effects and 234 (86%) had no effects. Synergistic activity was observed mostly when the Apocynaceae extracts were combined with rifampicin or cefazolin. Interestingly, 10 out of 17 combinations between the extracts and rifampicin displayed synergistic or partial synergistic behaviors. Holarrhena antidysenterica extract was additionally tested to restore rifampicin activity against clinical isolates of MDR and XDR A. baumannii. With respect to total or partial synergy, 70% was XDR A. baumannii isolates and 66% was MDR A. baumannii isolates. Holarrhena antidysenterica extract clearly demonstrated the ability to restore rifampicin activity against both A. baumannii ATCC19606 and clinically isolated A. baumannii. Additional studies examining its active principles as well as mechanisms of actions such as the effects on efflux pumps and outer membrane permeability alterations are recommended. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  14. The Rate of Inducible MLSB Resistance in the Methicillin-Resistant Staphylococci Isolated From Clinical Samples.

    Science.gov (United States)

    Toka Özer, Türkan

    2016-09-01

    Staphylococci are one of the most common pathogens in nasocomial and community-acquired infections. Methicillin-resistant staphylococci are known to be resistant against all beta-lactam antibiotics. Therefore, non-beta-lactam antibiotics such as macrolide and lincosamides can be used. Resistance to those antibiotics may lead to therapeutic failure. The purpose of the present study was to determine the prevalence of macrolide-lincosamide-streptogramin B (MLSB ) resistance by using D-test in staphylococcal isolates from various clinical samples. Seventy-one methicillin-resistant Staphylococcus isolates (six S. aureus, 65 coagulase negative staphylococci) were included in this study. Staphylococci were identified with conventional methods. According to Clinical Laboratory Standards Institute (CLSI) criteria, susceptibility testing was performed by Kirby-Bauer disk diffusion method. One of six (16.6%) methicillin-resistant S. aureus isolates and 19 of 65 (29.2%) methicillin-resistant coagulase-negative staphylococci (MR-CNS) were detected as D-test positive. Twenty of 71 (28.1%) staphylococcal isolates detected as D-test positive. Inducible clindamycin resistance was found at a higher rate in MR-CNS. Since the resistant community and hospital acquired staphylococcal infections have become a therapeutic problem, it is very important to detect MLSB resistance routinely in microbiology laboratories. D-test is a cheap and reliable diagnostic method that can be performed in every laboratory. © 2015 Wiley Periodicals, Inc.

  15. The determination of optimal cells disintegration method of Candida albicans and Candida tropicalis fungals

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    M. V. Rybalkyn

    2014-08-01

    Full Text Available Candidiasis is common infectious disease that affects the mucous membranes, skin, nails, hair, and internal organs. Now Ukraine has neither domestic nor registered imported vaccine against candidiasis. The development of vaccine for prevention and treatment of candidiasis is a key issue in modern medicine and pharmacy. Similar research is actively conducted in many countries of the world: Russia, USA, Japan and others. It should be noted that researchers have not yet reached a consensus view which vaccine is most effective with candidiasis. There are several types of vaccines: live, inactivated, subunit and others. In this article, we consider getting the potential subunit vaccine from Candida albicans and Candida tropicalis fungi. Subunit vaccine is composed of fragments of antigens that can provide an adequate immune response. These vaccines can be represented by particles of microbes. It is known that the main substances in cells of genus Candida fungi, which have antigenic properties, are proteins and polysaccharides. However, the question of their localization in the layers of the cell wall and cytoplasm nowadays require more detailed studies. Many researchers to highlight cytoplasm antigens and all the other layers of the cell use the following methods: grinding cells with quartz sand, destroying them in different machine disintegrating, freezing and thawing a multi others. To obtain potential subunit vaccine fungi were rejected by methods that are based on the processing of biomass fungi chemicals (extraction, hydrolysis. The aim of this work was to study experimentally the destruction method of Candida albicans and Candida tropicalis fungi. Cells of Candida albicans fungi strain CCM 335-867 and Candida tropicalis fungi strain 20336 ATTS have been separately cultured in vitro on agar Sabouraud at 25 ± 2º C for 48 hours and then washed by 10 ml of sterile 0.9% isotonic sodium chloride solution. Cell suspension of Candida albicans and

  16. [Characterization of clinical isolates of Mycobacterium tuberculosis from HIV positive individuals in Colombia, 2012].

    Science.gov (United States)

    Castro, Claudia; Ricardo, Alba; Zabaleta, Angie; Llerena, Claudia; Puerto, Gloria

    2017-01-24

    One third of the increase in tuberculosis cases is attributed to the spread of HIV. In 2012, 1,397 HIV-associated tuberculosis cases were reported in Colombia, i.e., 11.8% of the total cases. Molecular epidemiology tools help to understand the transmission of tuberculosis. To characterize clinical isolates of Mycobacterium tuberculosis derived from HIV-infected individuals, received at the Laboratorio Nacional de Referencia in the Instituto Nacional de Salud. This was a descriptive observational study. We analyzed 63 isolates of M. tuberculosis from HIV-infected individuals. Identification, drug susceptibility and genotyping assays were performed. Of the new cases evaluated, three (5.0%) were resistant to isoniazid combined with streptomycin; two (3.3%) to rifampicin, and one (1.6%) to isoniazid. Previously treated cases were sensitive. No multidrug resistance was evident. Among the predominant genotypes, 20 isolates were (31.7%) LAM9, eight (12.7%), H1, and seven (11.1%), T1. Nineteen isolates corresponded to orphan patterns. One single grouping was observed among tested isolates. We found no statistically significantdifference between the proportions of the antituberculous drug resistance and genotypes. We found resistant isolates to the most powerful drugs, rifampicin and isoniazid, among new cases, showing the transmission of resistant strains. Genetic families of M. tuberculosis LAM9, T1 and H1 correspond to those described in the general population. We detected no active transmission among studied isolates. More comprehensive studies are needed to assess the real situation of HIV associated tuberculosis in the country regarding sensitivity and transmission.

  17. Species distribution of clinical Acinetobacter isolates revealed by different identification techniques.

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    Jianfeng Wang

    Full Text Available A total of 2582 non-duplicate clinical Acinetobacter spp. isolates were collected to evaluate the performance of four identification methods because it is important to identify Acinetobacter spp. accurately and survey the species distribution to determine the appropriate antimicrobial treatment. Phenotyping (VITEK 2 and VITEK MS and genotyping (16S rRNA and rpoB gene sequencing methods were applied for species identification, and antimicrobial susceptibility test of imipenem and meropenem was performed with a disk diffusion assay. Generally, the phenotypic identification results were quite different from the genotyping results, and their discrimination ability was unsatisfactory, whereas 16S rRNA and rpoB gene sequencing showed consistent typing results, with different resolution. Additionally, A. pittii, A. calcoaceticus and A. nosocomialis, which were phylogenetically close to A. baumannii, accounted for 85.5% of the non-A. baumannii isolates. One group, which could not be clustered with any reference strains, consisted of 11 isolates and constituted a novel Acinetobacter species that was entitled genomic species 33YU. None of the non-A. baumannii isolates harbored a blaOXA-51-like gene, and this gene was disrupted by ISAba19 in only one isolate; it continues to be appropriate as a genetic marker for A. baumannii identification. The resistance rate of non-A. baumannii isolates to imipenem and/or meropenem was only 2.6%, which was significantly lower than that of A. baumannii. Overall, rpoB gene sequencing was the most accurate identification method for Acinetobacter species. Except for A. baumannii, the most frequently isolated species from the nosocomial setting were A. pittii, A. calcoaceticus and A. nosocomialis.

  18. Species Distribution of Clinical Acinetobacter Isolates Revealed by Different Identification Techniques

    Science.gov (United States)

    Feng, Ye; Fu, Ying; Jiang, Yan; Wang, Haiping; Yu, Yunsong

    2014-01-01

    A total of 2582 non-duplicate clinical Acinetobacter spp. isolates were collected to evaluate the performance of four identification methods because it is important to identify Acinetobacter spp. accurately and survey the species distribution to determine the appropriate antimicrobial treatment. Phenotyping (VITEK 2 and VITEK MS) and genotyping (16S rRNA and rpoB gene sequencing) methods were applied for species identification, and antimicrobial susceptibility test of imipenem and meropenem was performed with a disk diffusion assay. Generally, the phenotypic identification results were quite different from the genotyping results, and their discrimination ability was unsatisfactory, whereas 16S rRNA and rpoB gene sequencing showed consistent typing results, with different resolution. Additionally, A. pittii, A. calcoaceticus and A. nosocomialis, which were phylogenetically close to A. baumannii, accounted for 85.5% of the non-A. baumannii isolates. One group, which could not be clustered with any reference strains, consisted of 11 isolates and constituted a novel Acinetobacter species that was entitled genomic species 33YU. None of the non-A. baumannii isolates harbored a bla OXA-51-like gene, and this gene was disrupted by ISAba19 in only one isolate; it continues to be appropriate as a genetic marker for A. baumannii identification. The resistance rate of non-A. baumannii isolates to imipenem and/or meropenem was only 2.6%, which was significantly lower than that of A. baumannii. Overall, rpoB gene sequencing was the most accurate identification method for Acinetobacter species. Except for A. baumannii, the most frequently isolated species from the nosocomial setting were A. pittii, A. calcoaceticus and A. nosocomialis. PMID:25120020

  19. Characterization and Antimicrobial Resistance of Salmonella Typhimurium Isolates from Clinically Diseased Pigs in Korea.

    Science.gov (United States)

    Oh, Sang-Ik; Kim, Jong Wan; Chae, Myeongju; Jung, Ji-A; So, Byungjae; Kim, Bumseok; Kim, Ha-Young

    2016-11-01

    This study investigated the prevalence of Salmonella enterica serovar and antimicrobial resistance in Salmonella Typhimurium isolates from clinically diseased pigs collected from 2008 to 2014 in Korea. Isolates were also characterized according to the presence of antimicrobial resistance genes and pulsed-field gel electrophoresis patterns. Among 94 Salmonella isolates, 81 (86.2%) were identified as being of the Salmonella Typhimurium serotype, followed by Salmonella Derby (6 of 94, 6.4%), Salmonella 4,[5],12:i:- (4 of 94, 4.3%), Salmonella Enteritidis (2 of 94, 2.1%), and Salmonella Brandenburg (1 of 94, 1.1%). The majority of Salmonella Typhimurium isolates were resistant to tetracycline (92.6%), followed by streptomycin (88.9%) and ampicillin (80.2%). Overall, 96.3% of Salmonella Typhimurium isolates showed multidrug-resistant phenotypes and commonly harbored the resistance genes bla TEM (64.9%), flo (32.8%), aadA (55.3%), strA (58.5%), strB (58.5%), sulII (53.2%), and tetA (61.7%). The pulsed-field gel electrophoresis analysis of 45 Salmonella Typhimurium isolates from individual farms revealed 27 distinct patterns that formed one major and two minor clusters in the dendrogram analysis, suggesting that most of the isolates (91.1%) from diseased pigs were genetically related. These findings can assist veterinarians in the selection of appropriate antimicrobial agents to combat Salmonella Typhimurium infections in pigs. Furthermore, they highlight the importance of continuous surveillance of antimicrobial resistance and genetic status in Salmonella Typhimurium for the detection of emerging resistance trends.

  20. Susceptibility of clinical isolates of multiresistant Pseudomonas aeruginosa to a hospital disinfectant and molecular typing

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    Célia Maria Carvalho Pereira Araujo Romão

    2005-08-01

    Full Text Available The aim of this study was to evaluate the susceptibility of 35 resistant Pseudomonas aeruginosa clinical isolates to a quaternary ammonium hospital disinfectant. The methodology was the AOAC Use-Dilution Test, with disinfectant at its use-concentration. In addition, the chromosomal DNA profile of the isolates were determined by macro-restriction pulsed field gel electrophoresis (PFGE method aiming to verify the relatedness among them and the behavior of isolates from the same group regarding the susceptibility to the disinfectant. Seventy one percent of the isolates were multiresistant to antibiotics and 43% showed a reduced susceptibility to the disinfectant. The PFGE methodology detected 18 major clonal groups. We found isolates with reduced susceptibility to the disinfectant and we think that these are worrying data that should be further investigated including different organisms and chemical agents in order to demonstrate that microorganisms can be destroyed by biocide as necessary. We also found strains of the same clonal groups showing different susceptibility to the disinfectant. This is an interesting observation considering that only few works are available about this subject. PFGE profile seems not to be a reliable marker for resistance to disinfectants.

  1. Epidemiologic evaluation of Vancomycin Resistant genes in Enterococcus spp. isolated from clinical samples

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    Omid Teymournejad

    2011-09-01

    Full Text Available Background & Objectives: Isolation of vancomycin resistant Enterococcus from clinical samples is very important. The aim of this study was evaluation of phenotype and genotype of van genes in vancomycine resistant Enterococcus. Materials and Methods: 411 Enterococcus isolates were collected from selected Tehran’s hospitals between March 2004 and December 2007. The enterococcal isolates were identified by biochemical confirmation tests. Resistance of each isolate to vancomycin determined by disk diffusion and agar dilution test. The presence of the vanA, B, C, D, E resistance gene was assessed by PCR. Results: 185(45% and 23(5.6% with disc-diffusion method and agar-dilution method were resistant to vancomucin (VRE and all of VREs were Enterococcus faecium. 12 (52.2%, 7(30.4% of the VRE isolates had vanA, vanB and 3(13% had both of vanA and vanB gene. Conclusion: Most important mechanism for high level resistance to vancomycin is presence of van genes and these genes can transfer between Enterococci. Significance of investigation in molecular level of resistance to vancomycin was due to relation between phenotypic resistant and presence of van genes.

  2. Clinical illnesses associated with isolation of dysgonic fermenter 3 from stool samples.

    OpenAIRE

    Blum, R N; Berry, C D; Phillips, M G; Hamilos, D L; Koneman, E W

    1992-01-01

    The clinical significance of the fastidious organism DF-3 isolated from stool cultures is unclear. We sought to improve our understanding of this organism and to further define its association with human disease. Stool cultures for DF-3 were obtained from three sources: an ongoing study of enteric pathogens in patients infected with the human immunodeficiency virus, a screening procedure in which all stool samples submitted for Clostridium difficile toxin assay were cultured for DF-3, and sto...

  3. Antimicrobial susceptibility of Streptococcus suis isolated from clinically healthy swine in Brazil

    OpenAIRE

    Soares, Taíssa Cook Siqueira; Paes, Antonio Carlos; Megid, Jane; Ribolla, Paulo Eduardo Martins; Paduan, Karina dos Santos; Gottschalk, Marcelo

    2014-01-01

    Streptococcus suis is an important pathogen in the swine industry. This study is the first to report on the antimicrobial susceptibility of S. suis isolated from clinically healthy pigs in Brazil; the fourth major pork producer in the world. The antimicrobial susceptibility of 260 strains was determined by disc diffusion method. Strains were commonly susceptible to ceftiofur, cephalexin, chloramphenicol, and florfenicol, with more than 80% of the strains being susceptible to these antimicrobi...

  4. A clinical isolate of transposon Tn5 expressing streptomycin resistance in Escherichia coli.

    OpenAIRE

    Genilloud, O; Blázquez, J; Mazodier, P; Moreno, F

    1988-01-01

    The central region of transposon Tn5 carries three antibiotic resistance markers: neo, ble, and str. The str gene codes for a phosphotransferase that inactivates streptomycin. This activity is phenotypically expressed in several gram-negative bacteria but not in Escherichia coli. We identified a Tn5 variant in E. coli clinical isolates that express streptomycin resistance. This transposon carries a 6-base-pair deletion within the str gene, near the 3' end. The same kind of mutation had been p...

  5. SUSCEPTIBILITY OF FOOD PRESERVATIVES ON MRSA AND MSSA ISOLATED FROM CLINICAL SAMPLES

    OpenAIRE

    Mamatha.C * and Dr. M. Thangavel

    2017-01-01

    Food preservatives are those substances which prevent spoilage caused by microbial or chemical causes. These preservatives may be natural or artificial. Natural preservatives are a hundred percent safe although the effectiveness lasts for shorter duration as compared with the artificial ones. Staphylococcus aureus was isolated from various clinical samples and confirmation was done using various biochemical tests. Antibiogram revealed the presence of 22 MRSA islolates and also the sensitivity...

  6. In vitro antibacterial potency of Butea monosperma Lam. against 12 clinically isolated multidrug resistant bacteria

    OpenAIRE

    Sahu, Mahesh Chandra; Padhy, Rabindra Nath

    2013-01-01

    Objective: To investigate the antibacterial activity, using cold and hot extraction procedures with five solvents, petroleum ether, acetone, ethanol, methanol and water to validate medicinal uses of Butea monosperma Lam (B. monosperma) in controlling infections; and to qualitatively estimate phytochemical constituents of leaf-extracts of the plant. Methods: The antibacterial activity of leaf-extracts was evaluated by the agar-well diffusion method against clinically isolated 12...

  7. Clinically Isolated Syndromes Suggestive of Multiple Sclerosis: An Optical Coherence Tomography Study

    OpenAIRE

    Oreja-Guevara, Celia; Noval, Susana; Alvarez-Linera, Juan; Gabaldón, Laura; Manzano, Beatriz; Chamorro, Beatriz; Diez-Tejedor, Exuperio

    2012-01-01

    BACKGROUND: Optical coherence tomography (OCT) is a simple, high-resolution technique to quantify the thickness of retinal nerve fiber layer (RNFL), which provides an indirect measurement of axonal damage in multiple sclerosis (MS). This study aimed to evaluate RNFL thickness in patients at presentation with clinically isolated syndromes (CIS) suggestive of MS. METHODOLOGY: This was a cross-sectional study. Twenty-four patients with CIS suggestive of MS (8 optic neuritis [ON], 6 spinal cord s...

  8. Strong lethality and teratogenicity of strobilurins on Xenopus tropicalis embryos: Basing on ten agricultural fungicides

    International Nuclear Information System (INIS)

    Li, Dan; Liu, Mengyun; Yang, Yongsheng; Shi, Huahong; Zhou, Junliang; He, Defu

    2016-01-01

    Agricultural chemical inputs have been considered as a risk factor for the global declines in amphibian populations, yet the application of agricultural fungicides has increased dramatically in recent years. Currently little is known about the potential toxicity of fungicides on the embryos of amphibians. We studied the effects of ten commonly used fungicides (four strobilurins, two SDHIs, two triazoles, fludioxonil and folpet) on Xenopus tropicalis embryos. Lethal and teratogenic effects were respectively examined after 48 h exposure. The median lethal concentrations (LC50s) and the median teratogenic concentrations (TC50s) were determined in line with actual exposure concentrations. These fungicides except two triazoles showed obvious lethal effects on embryos; however LC50s of four strobilurins were the lowest and in the range of 6.81–196.59 μg/L. Strobilurins, SDHIs and fludioxonil induced severe malformations in embryos. Among the ten fungicides, the lowest TC50s were observed for four strobilurins in the range of 0.61–84.13 μg/L. The teratogenicity shared similar dose–effect relationship and consistent phenotypes mainly including microcephaly, hypopigmentation, somite segmentation and narrow fins. The findings indicate that the developmental toxicity of currently-used fungicides involved with ecologic risks on amphibians. Especially strobilurins are highly toxic to amphibian embryos at μg/L level, which is close to environmentally relevant concentrations. - Highlights: • Effects of ten agricultural fungicides were tested on Xenopus tropicalis embryos. • Strobilurin fungicides showed strong lethal and teratogenic effects on embryos. • Lowest LC50 and TC50 were observed for strobilurins in ten fungicides. • μg/L level of toxic concentrations for strobilurins was environmentally relevant. • Teratogenicity shared similar dose–effect relationship and main phenotypes. - Strobilurins induced strong lethality and teratogenicity on Xenopus

  9. Cerebral Venous Thrombosis in a Patient with Clinically Isolated Spinal Cord Syndrome

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    Jasem Yousef Al-Hashel

    2013-01-01

    Full Text Available Background. The association between cerebral venous thrombosis (CVT and multiple sclerosis (MS has already been reported in patients with clinically definite MS in relation to intravenous methylprednisolone (IVMP or previously performed lumbar puncture (LP. Case Summery. We report a 29-year-old Indian female who presented with a clinically isolated spinal cord syndrome according to the revised 2010 McDonald Criteria. She developed CVT after a lumbar puncture and two days of finishing the course of IVMP. Conclusion. We conclude that the sequence of doing lumbar puncture followed by high-dose IVMP may increase the risk of CVT. A prophylactic anticoagulation may be indicated in this setting.

  10. Antibiotics resistance of Stenotrophomonas maltophilia strains isolated from various clinical specimens.

    Science.gov (United States)

    Çıkman, Aytekin; Parlak, Mehmet; Bayram, Yasemin; Güdücüoğlu, Hüseyin; Berktaş, Mustafa

    2016-03-01

    A limited number of antibiotics are recommended for the therapy of Stenotrophomonas maltophilia infections due to therapy difficulties caused by its numerous mechanisms of resistance. In this study conducted over a period of approximately 5 years we aimed to determine resistance rates of S. maltophilia based on drug classification recommended by Clinical and Laboratory Standards Institute. A total of 118 S. maltophilia strains isolated from various clinical specimens between January 2006 and June 2012 were included in the study. BD Phoenixautomated microbiology system (Becton Dickinson, USA) was utilized for species level identification and antibiotic susceptibility testing. Sixty seven of S. maltophilia strains were isolated from tracheal aspirate isolates, 17 from blood, 10 from sputum, 10 from wound and 14 from other clinical specimens. Levofloxacin was found to be the most effective antibiotic against S. maltophilia strains with resistance rate of 7.6%. The resistance rates to other antibiotics were as follows: chloramphenicol 18.2%, trimethoprim-sulfamethoxazole 20.3% and ceftazidime 72%. The study revealed that S. maltophilia is resistant to many antibiotics. The treatment of infections caused by S. maltophilia should be preferred primarily as levofloxacin, chloramphenicol, and TMP-SXT, respectively.

  11. Virulence diversity among bacteremic Aeromonas isolates: ex vivo, animal, and clinical evidences.

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    Po-Lin Chen

    Full Text Available BACKGROUND: The objective of this study was to compare virulence among different Aeromonas species causing bloodstream infections. METHODOLOGY/PRINCIPAL FINDINGS: Nine of four species of Aeromonas blood isolates, including A. dhakensis, A. hydrophila, A. veronii and A. caviae were randomly selected for analysis. The species was identified by the DNA sequence matching of rpoD. Clinically, the patients with A. dhakensis bacteremia had a higher sepsis-related mortality rate than those with other species (37.5% vs. 0%, P = 0.028. Virulence of different Aeromonas species were tested in C. elegans, mouse fibroblast C2C12 cell line and BALB/c mice models. C. elegans fed with A. dhakensis and A. caviae had the lowest and highest survival rates compared with other species, respectively (all P values <0.0001. A. dhakensis isolates also exhibited more cytotoxicity in C2C12 cell line (all P values <0.0001. Fourteen-day survival rate of mice intramuscularly inoculated with A. dhakensis was lower than that of other species (all P values <0.0001. Hemolytic activity and several virulence factor genes were rarely detected in the A. caviae isolates. CONCLUSIONS/SIGNIFICANCE: Clinical data, ex vivo experiments, and animal studies suggest there is virulence variation among clinically important Aeromonas species.

  12. Detection of inducible clindamycin resistance among Staphylococcal isolates from different clinical specimens in western India.

    Science.gov (United States)

    Pal, N; Sharma, B; Sharma, R; Vyas, L

    2010-01-01

    Macrolide (MLS B ) resistance is the most widespread and clinically important mechanism of resistance encountered with Gram-positive organisms. Resistance may be constitutive (cMLS B phenotype) or inducible (iMLS B phenotype). The iMLS B phenotypes are not differentiated by using standard susceptibility test methods, but can be distinguished by erythromycin-clindamycin disk approximation test (D-test) and demonstration of resistance genes by molecular methods. To demonstrate in vitro inducible clindamycin resistance (iMLS B ) in erythromycin-resistant (ER) and clindamycin-susceptible (CLI-S) clinical isolates of Staphylococci spp., and interpretation of susceptibility tests to guide therapy. Eight hundred and fifty-one isolates of Staphylococci spp. were recovered from various clinical specimens. All the Staphylococcal spp. were identified by conventional microbiological methods including colony morphology, Gram stain, catalase, slide coagulase and tube coagulase. Antibiotic susceptibility testing was performed by Kirby Bauer disc diffusion method. Erythromycin-resistant isolates were examined for inducible clindamycin resistance (iMLS B ) by using double disk approximation test (D-test) at 15 mm disk separation. The Staphylococci spp. isolated were 379 S. aureus [31.60% methicillin-resistant S. aureus (MRSA), 12.92% methicillin-sensitive S. aureus (MSSA)] and 472 coagulase-negative Staphylococci (CNS) [37.60% methicillin-resistant coagulase-negative Staphylococci (MRCNS), 17.86% methicillin-sensitive coagulase-negative Staphylococci (MSCNS)]. Four hundred and thirty (50.52%) Staphylococcal spp. isolates showed erythromycin resistance. Constitutive resistance was demonstrated in 202 (46.97%), inducible clindamycin resistance (iMLS B ) in 101 (23.48%), and non-inducible (MS) in 127 (29.53%). Two distinct induction phenotypes, D (18.13%) and D + (5.34%) were observed. All iMLS B isolates were susceptible to linezolid and vancomycin while 78.78% to ciprofloxacin

  13. Detection of inducible clindamycin resistance among Staphylococcal isolates from different clinical specimens in western India

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    Pal N

    2010-01-01

    Full Text Available Background: Macrolide (MLS B resistance is the most widespread and clinically important mechanism of resistance encountered with Gram-positive organisms. Resistance may be constitutive (cMLS B phenotype or inducible (iMLS B phenotype. The iMLS B phenotypes are not differentiated by using standard susceptibility test methods, but can be distinguished by erythromycin-clindamycin disk approximation test (D-test and demonstration of resistance genes by molecular methods. Aims: To demonstrate in vitro inducible clindamycin resistance (iMLS B in erythromycin-resistant (ER and clindamycin-susceptible (CLI-S clinical isolates of Staphylococci spp., and interpretation of susceptibility tests to guide therapy. Materials and Methods: Eight hundred and fifty-one isolates of Staphylococci spp. were recovered from various clinical specimens. All the Staphylococcal spp. were identified by conventional microbiological methods including colony morphology, Gram stain, catalase, slide coagulase and tube coagulase. Antibiotic susceptibility testing was performed by Kirby Bauer disc diffusion method. Erythromycin-resistant isolates were examined for inducible clindamycin resistance (iMLS B by using double disk approximation test (D-test at 15 mm disk separation. Results: The Staphylococci spp. isolated were 379 S. aureus [31.60% methicillin-resistant S. aureus (MRSA, 12.92% methicillin-sensitive S. aureus (MSSA] and 472 coagulase-negative Staphylococci (CNS [37.60% methicillin-resistant coagulase-negative Staphylococci (MRCNS, 17.86% methicillin-sensitive coagulase-negative Staphylococci (MSCNS]. Four hundred and thirty (50.52% Staphylococcal spp. isolates showed erythromycin resistance. Constitutive resistance was demonstrated in 202 (46.97%, inducible clindamycin resistance (iMLS B in 101 (23.48%, and non-inducible (MS in 127 (29.53%. Two distinct induction phenotypes, D (18.13% and D + (5.34% were observed. All iMLS B isolates were susceptible to linezolid and

  14. Microbiological features and clinical impact of the type VI secretion system (T6SS) in Acinetobacter baumannii isolates causing bacteremia.

    Science.gov (United States)

    Kim, Jungok; Lee, Ji-Young; Lee, Haejeong; Choi, Ji Young; Kim, Dae Hun; Wi, Yu Mi; Peck, Kyong Ran; Ko, Kwan Soo

    2017-10-03

    We investigated the genetic background and microbiological features of T6SS-positive Acinetobacter baumannii isolates and clinical impact of the T6SS in patients with A. baumannii bacteremia. One hundred and 62 A. baumannii isolates from patients with bacteremia in 2 tertiary-care hospitals in Korea were included in this study. Approximately one-third (51/162, 31.5%) of the A. baumannii clinical isolates possessed the hcp gene, and the hcp-positive isolates were found in several genotypes in multilocus sequence typing. The expression and secretion of Hcp protein varied among the clinical isolates. A. baumannii isolates with detectable Hcp secretion (T6SS+) could better outcompete Escherichia coli compared with T6SS- isolates, including hcp-negative and inactivated hcp-positive isolates. In addition, T6SS+ isolates showed higher biofilm-forming activity and better survival in the presence of normal human serum than the T6SS- isolates. T6SS+ isolates were more frequently detected in patients with catheter-related bloodstream infection, haematopoietic stem cell transplant recipients, and patients receiving immunosuppressive agents. However, T6SS was not a prognostic factor for mortality. Our results suggest that the T6SS of A. baumannii is associated with virulence and contributes to infections in immunocompromised patients and those with implanted medical devices.

  15. Molecular analysis of Rv0679c and Rv0180c genes of Mycobacterium tuberculosis from clinical isolates of pulmonary tuberculosis

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    L Rupa

    2016-01-01

    Full Text Available Context: Two novel proteins/genes Rv0679c and Rv0180c of Mycobacterium tuberculosis (MTB H37Rv were classified as a hypothetical membrane and transmembrane proteins which might have a role in the invasion. Molecular analysis of these genes in human clinical isolates of pulmonary tuberculosis (PTB patients was not well characterised. Aims: To assess the molecular diversity of Rv0679c and Rv0180c genes of MTB from clinical isolates of PTB patients. Settings and Design: DNA from 97 clinical isolates was extracted and subjected to amplification using selective primers by polymerase chain reaction (PCR. The PCR product obtained was sequenced commercially. Patients and Methods: Clinical isolates obtained from tuberculosis patients were investigated for polymorphisms in the Rv0679c and Rv0180c genes by PCR and DNA sequencing. Genomic DNA isolated by cetyltrimethylammonium bromide method was used for amplification of genes. Results: Rv0679c gene was highly conserved in 61 out of 65 clinical isolates assessed for sequence homology with wild-type H37Rv gene and was identical using ClustalW. Fifty-five out of 78 (70.5% clinical isolates assessed for Rv0180c were positive for single nucleotide polymorphism (SNP at 258th position where the nucleotide G was replaced with T (G to T. In clinical isolates of untreated cases, the frequency was 54.5% for SNP at 258th position which is low compared to cases undergoing treatment where the frequency was 73.1%. Conclusions: Molecular analysis of Rv0180c in clinical isolates of PTB assessed in this study was the first report, where an SNP at 258th position G to T was identified within the gene. Rv0679c gene was highly conserved (94%, within Indian clinical isolates as compared to reports from other nations.

  16. Molecular Epidemiology and Colistin Resistant Mechanism ofmcr-Positive andmcr-Negative Clinical IsolatedEscherichia coli.

    Science.gov (United States)

    Luo, Qixia; Yu, Wei; Zhou, Kai; Guo, Lihua; Shen, Ping; Lu, Haifeng; Huang, Chen; Xu, Hao; Xu, Shaoyan; Xiao, Yonghong; Li, Lanjuan

    2017-01-01

    Transmissible colistin resistance mediated by the mcr gene has been reported worldwide, but clinical isolates of mcr -negative colistin-resistant Escherichia coli are rarely reported. The aim of this study was to evaluate the mechanism of colistin resistance among mcr -positive and mcr -negative E. coli clinical isolates by performing a molecular epidemiological surveillance. For the first time ever, we show nearly the same isolation ratio for mcr -negative and mcr -positive colistin-resistant clinical isolates (47.5 and 52.5%, respectively), with no demonstrable nosocomial transmission. We provide evidence for the prevalence of the mcr -positive IncX4 plasmid and its high potential for horizontal transfer, with no obvious sequence type (ST) preference. In addition, the minimal inhibitory concentrations (MICs) of colistin of the mcr -negative E. coli isolates were obviously higher than those of mcr -positive isolates. Apart from the usually detected genes, i.e., pmrAB, phoPQ , and mgrB , other genes may be associated with the colistin resistance in mcr -negative E. coli . To the best of our knowledge, this is the first paper to report the molecular epidemiological surveillance and the proper mechanism of colistin resistance in mcr -negative E. coli clinical isolates. Together, the results show that colistin resistance was prevalent not only in the mcr -positive clinical E. coli isolates but also in the mcr -negative isolates.

  17. Molecular Epidemiology and Colistin Resistant Mechanism of mcr-Positive and mcr-Negative Clinical Isolated Escherichia coli

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    Qixia Luo

    2017-11-01

    Full Text Available Transmissible colistin resistance mediated by the mcr gene has been reported worldwide, but clinical isolates of mcr-negative colistin-resistant Escherichia coli are rarely reported. The aim of this study was to evaluate the mechanism of colistin resistance among mcr-positive and mcr-negative E. coli clinical isolates by performing a molecular epidemiological surveillance. For the first time ever, we show nearly the same isolation ratio for mcr-negative and mcr-positive colistin-resistant clinical isolates (47.5 and 52.5%, respectively, with no demonstrable nosocomial transmission. We provide evidence for the prevalence of the mcr-positive IncX4 plasmid and its high potential for horizontal transfer, with no obvious sequence type (ST preference. In addition, the minimal inhibitory concentrations (MICs of colistin of the mcr-negative E. coli isolates were obviously higher than those of mcr-positive isolates. Apart from the usually detected genes, i.e., pmrAB, phoPQ, and mgrB, other genes may be associated with the colistin resistance in mcr-negative E. coli. To the best of our knowledge, this is the first paper to report the molecular epidemiological surveillance and the proper mechanism of colistin resistance in mcr-negative E. coli clinical isolates. Together, the results show that colistin resistance was prevalent not only in the mcr-positive clinical E. coli isolates but also in the mcr-negative isolates.

  18. Antimicrobial drug resistance among clinically relevant bacterial isolates in sub-Saharan Africa: a systematic review.

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    Leopold, Stije J; van Leth, Frank; Tarekegn, Hayalnesh; Schultsz, Constance

    2014-09-01

    Little is known about the prevalence of antimicrobial resistance (AMR) amongst bacterial pathogens in sub-Saharan Africa (sSA), despite calls for continent-wide surveillance to inform empirical treatment guidelines. We searched PubMed and additional databases for susceptibility data of key pathogens for surveillance, published between 1990 and 2013. Extracted data were standardized to a prevalence of resistance in populations of isolates and reported by clinical syndrome, microorganism, relevant antimicrobial drugs and region. We identified 2005 publications, of which 190 were analysed. Studies predominantly originated from east sSA (61%), were hospital based (60%), were from an urban setting (73%) and reported on isolates from patients with a febrile illness (42%). Quality procedures for susceptibility testing were described in resistance to chloramphenicol in Enterobacteriaceae, isolated from patients with a febrile illness, ranged between 31.0% and 94.2%, whilst MP of resistance to third-generation cephalosporins ranged between 0.0% and 46.5%. MP of resistance to nalidixic acid in Salmonella enterica Typhi ranged between 15.4% and 43.2%. The limited number of studies providing prevalence data on AMR in Gram-positive pathogens or in pathogens isolated from patients with a respiratory tract infection, meningitis, urinary tract infection or hospital-acquired infection suggested high prevalence of resistance to chloramphenicol, trimethoprim/sulfamethoxazole and tetracycline and low prevalence to third-generation cephalosporins and fluoroquinolones. Our results indicate high prevalence of AMR in clinical bacterial isolates to antimicrobial drugs commonly used in sSA. Enhanced approaches for AMR surveillance are needed to support empirical therapy in sSA. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. Comparative analysis and supragenome modeling of twelve Moraxella catarrhalis clinical isolates

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    Hermans Peter WM

    2011-01-01

    Full Text Available Abstract Background M. catarrhalis is a gram-negative, gamma-proteobacterium and an opportunistic human pathogen associated with otitis media (OM and exacerbations of chronic obstructive pulmonary disease (COPD. With direct and indirect costs for treating these conditions annually exceeding $33 billion in the United States alone, and nearly ubiquitous resistance to beta-lactam antibiotics among M. catarrhalis clinical isolates, a greater understanding of this pathogen's genome and its variability among isolates is needed. Results The genomic sequences of ten geographically and phenotypically diverse clinical isolates of M. catarrhalis were determined and analyzed together with two publicly available genomes. These twelve genomes were subjected to detailed comparative and predictive analyses aimed at characterizing the supragenome and understanding the metabolic and pathogenic potential of this species. A total of 2383 gene clusters were identified, of which 1755 are core with the remaining 628 clusters unevenly distributed among the twelve isolates. These findings are consistent with the distributed genome hypothesis (DGH, which posits that the species genome possesses a far greater number of genes than any single isolate. Multiple and pair-wise whole genome alignments highlight limited chromosomal re-arrangement. Conclusions M. catarrhalis gene content and chromosomal organization data, although supportive of the DGH, show modest overall genic diversity. These findings are in stark contrast with the reported heterogeneity of the species as a whole, as wells as to other bacterial pathogens mediating OM and COPD, providing important insight into M. catarrhalis pathogenesis that will aid in the development of novel therapeutic regimens.

  20. Research article: clinical characteristics of isolated anterior cerebral artery territory infarction due to arterial dissection.

    Science.gov (United States)

    Nagamine, Yuito; Fukuoka, Takuya; Hayashi, Takeshi; Kato, Yuji; Deguchi, Ichiro; Maruyama, Hajime; Horiuchi, Yohsuke; Sano, Hiroyasu; Mizuno, Satoko; Tanahashi, Norio

    2014-01-01

    Isolated brain infarction in the anterior cerebral artery (ACA) territory is rare, and its etiology has not yet been fully elucidated. Thus, we aimed to determine the etiologic and clinical characteristics of patients with isolated ACA territory infarction due to arterial dissection. Of 2315 patients with acute cerebral infarction admitted to our hospital between April 2007 and September 2013, 34 patients (1.5%; 28 men, 6 women; mean age, 65 ± 15 years) suffered isolated ACA territory infarction. We performed cranial magnetic resonance (MR) imaging and MR angiography for all the patients. Whenever possible, we also performed 3-dimensional computed tomography angiography, digital subtraction angiography, and MR cisternography to diagnose the stroke subtype. The stroke subtypes of the 34 patients with isolated ACA territory infarction were atherothrombotic infarction, cardioembolic infarction, arterial dissection, and unclassified in 11 patients (32%), 11 patients (32%), 11 patients (32%), and 1 patient (3%), respectively. The mean ages at onset were 48 ± 9 and 72 ± 11 years in the dissection and nondissection groups, respectively (P < .001). Headaches were present at onset in 4 patients (36%) and 1 patient (4%) with and without dissection, respectively (P = .026). Blood pressure at onset was significantly higher among patients with dissection (systolic, 179 ± 34 mm Hg; diastolic, 102 ± 17 mm Hg) than among patients without dissection (systolic, 155 ± 30 mm Hg; diastolic, 86 ± 21 mm Hg; P < .05), and d-dimer values were significantly lower among patients with dissection (P = .034). Favorable clinical outcome (modified Rankin Scale score, 0-2) at discharge was achieved in 9 patients (82%) and 10 patients (43%) with and without dissection, respectively (P = .035). Patients with isolated ACA territory infarction demonstrated a relatively high frequency of dissection (32%). Patients with dissection were younger, had a higher frequency of headaches, and

  1. Impact of Hypoxia on Drug Resistance and Growth Characteristics of Mycobacterium tuberculosis Clinical Isolates.

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    Zhonghua Liu

    Full Text Available Mycobacterium tuberculosis (MTB is a specific aerobic bacterium, but can survive under hypoxic conditions, such as those in lung cheese necrosis, granulomas, or macrophages. It is not clear whether the drug sensitivity and growth characteristics of MTB under hypoxic conditions are different from those under aerobic conditions. In this study, we examined the drug resistance and growth characteristics of MTB clinical isolates by a large sample of in vitro drug susceptibility tests, using an automatic growth instrument. Under hypoxic conditions, variance in drug resistance was observed in nearly one-third of the MTB strains and was defined as MTB strains with changed drug sensitivity (MTB-CDS. Among these strains, resistance in a considerable proportion of clinical strains was significantly increased, and some strains emerged as multi-drug resistant. Growth test results revealed a high growth rate and large survival number in macrophages under hypoxia in MTB-CDS. According to the results of fluorescence quantitative PCR, the expression of some genes, including RegX3 (involving RIF resistance, Rv0194 (efflux pump gene, four genes related to transcription regulation (KstR, DosR, Rv0081 and WhiB3 and gene related to translation regulation (DATIN, were upregulated significantly under hypoxic conditions compared to that under aerobic conditions (p < 0.05. Thus, we concluded that some MTB clinical isolates can survive under hypoxic conditions and their resistance could change. As for poor clinical outcomes in patients, based on routine drug susceptibility testing, drug susceptibility tests for tuberculosis under hypoxic conditions should also be recommended. However, the detailed mechanisms of the effect of hypoxia on drug sensitivity and growth characteristics of MTB clinical isolates still requires further study.

  2. Left atrial appendage isolation using percutaneous (endocardial/epicardial) devices: Pre-clinical and clinical experience.

    Science.gov (United States)

    Romero, Jorge; Natale, Andrea; Engstrom, Krysthel; Di Biase, Luigi

    2016-02-01

    Atrial fibrillation (AF) is the most common arrhythmia in the elderly population and it is associated with a four-fold to five-fold increased risk of thromboembolic events. It was not until the mid-1950s that the left atrial appendage (LAA) was identified as the main location of thrombus formation, particularly in patients with non-valvular AF. In this review, we explain at some extent its embryology, anatomy and physiology, and as well as the clinical and pre-clinical trials published to date testing the safety and efficacy of most LAA closure devices. Among those devices, the most studied include the PLAATO system (ev3 Endovascular, Plymouth, MN), the Amplatzer cardiac plug (St Jude, Golden Valley, MN; St. Jude Medical, Minneapolis, MN), the WATCHMAN device (Boston Scientific, Plymouth, MN; Atritech Inc., Plymouth, MN), and the LARIAT device (SentreHEART, Palo Alto, CA). Similarly, newer LAA closure devices currently under investigation such as the Transcatheter Patch (Custom Medical Devices, Athens, Greece), AEGIS, and the Coherex WaveCrest (Salt Lake City, UT) will also be discussed. Future perspectives and the need for well-designed prospective studies between devices and new oral anticoagulant drugs are also proposed. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Changes in antimicrobial resistance of clinical isolates of Acinetobacter baumannii group isolated in Greece, 2010-2015.

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    Dafopoulou, K; Tsakris, A; Pournaras, S

    2018-04-01

    In recent years, hospitals in southeastern Europe have faced dramatically high rates of antibiotic-resistant Acinetobacter baumannii. We analysed the evolution of resistance among clinical isolates of A. baumannii group obtained from nine tertiary hospitals throughout Greece over 6 years (2010-2015). Identification and antimicrobial susceptibility testing were performed using Vitek 2 or Microscan walkaway automated systems. Between 2010 and 2015, resistance to ampicillin/sulbactam increased from 46.2 to 88.2 % (P=0.021), resistance to gentamicin increased from 69.3 to 86.4 % (P=0.014) and resistance to tobramycin increased from 59.8 to 76.8 % (P=0.011). Imipenem resistance rates were consistently very high, ranging from 90.3 % in 2010 to 94.5 % in 2015 (P=0.198), while meropenem resistance rates increased from 82.6 % in 2010 to 94.8 % in 2015 (P=0.006). Resistance rates to trimethoprim/sulfamethoxazole showed a remarkable decreasing trend, declining from 90.2 % in 2010 to 69.1 % in 2015 (P=0.035). These evolutions render the treatment of A. baumannii infections particularly challenging and underline the need for enhanced infection control measures.

  4. The effect of environmental conditions on biofilm formation of Burkholderia pseudomallei clinical isolates.

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    Nur Siti K Ramli

    Full Text Available Burkholderia pseudomallei, a Gram-negative saprophytic bacterium, is the causative agent of the potentially fatal melioidosis disease in humans. In this study, environmental parameters including temperature, nutrient content, pH and the presence of glucose were shown to play a role in in vitro biofilm formation by 28 B. pseudomallei clinical isolates, including four isolates with large colony variants (LCVs and small colony variants (SCVs morphotypes. Enhanced biofilm formation was observed when the isolates were tested in LB medium, at 30 °C, at pH 7.2, and in the presence of as little as 2 mM glucose respectively. It was also shown that all SVCs displayed significantly greater capacity to form biofilms than the corresponding LCVs when cultured in LB at 37 °C. In addition, octanoyl-homoserine lactone (C(8-HSL, a quorum sensing molecule, was identified by mass spectrometry analysis in bacterial isolates referred to as LCV CTH, LCV VIT, SCV TOM, SCV CTH, 1 and 3, and the presence of other AHL's with higher masses; decanoyl-homoserine lactone (C(10-HSL and dodecanoyl-homoserine lactone (C(12-HSL were also found in all tested strain in this study. Last but not least, we had successfully acquired two Bacillus sp. soil isolates, termed KW and SA respectively, which possessed strong AHLs degradation activity. Biofilm formation of B. pseudomallei isolates was significantly decreased after treated with culture supernatants of KW and SA strains, demonstrating that AHLs may play a role in B. pseudomallei biofilm formation.

  5. Clinical illnesses associated with isolation of dysgonic fermenter 3 from stool samples.

    Science.gov (United States)

    Blum, R N; Berry, C D; Phillips, M G; Hamilos, D L; Koneman, E W

    1992-02-01

    The clinical significance of the fastidious organism DF-3 isolated from stool cultures is unclear. We sought to improve our understanding of this organism and to further define its association with human disease. Stool cultures for DF-3 were obtained from three sources: an ongoing study of enteric pathogens in patients infected with the human immunodeficiency virus, a screening procedure in which all stool samples submitted for Clostridium difficile toxin assay were cultured for DF-3, and stool samples submitted specifically for DF-3 culture. Retrospective clinical data were obtained from chart reviews of patients with positive cultures. Antimicrobial susceptibility testing and cell wall fatty acid analysis were performed for each DF-3 isolated. Eight isolates of DF-3 were obtained over a period of 8 months. All patients either had severe underlying disease or were immunocompromised, including three patients coinfected with human immunodeficiency virus and two patients with inflammatory bowel disease. The spectrum of clinical disease ranged from chronic diarrhea with a well-defined response to therapy for DF-3 to an asymptomatic carrier state. Cell wall fatty acid analysis of these isolates demonstrated a consistent pattern with a large peak of 12-methyltetradecanoate. DF-3, a fastidious gram-negative coccobacillus, can be recovered from stool cultures of immunocompromised patients by using selective media. The presence of 12-methyltetradecanoate in cell wall fatty acid analysis assists in identification. The increased use of a selective medium-(cefoperazone-vancomycin-amphotericin B) in the evaluation of diarrhea in immunocompromised hosts, including persons with inflammatory bowel disease, may better define the association of DF-3 with human gastrointestinal disease.

  6. Comparative effects of photodynamic therapy mediated by curcumin on standard and clinical isolate of Streptococcus mutans.

    Science.gov (United States)

    Tonon, Caroline C; Paschoal, Marco Aurélio; Correia, Marilia; Spolidório, Denise M P; Bagnato, Vanderlei S; Giusti, Juçaíra S M; Santos-Pinto, Lourdes

    2015-01-01

    The aim of this study was investigate the effect of photodynamic therapy (PDT) using curcumin (C) as a photosensitizing agent irradiated with an LED (L) in the blue wavelength as a light source on a standard and clinical isolate of Streptococcus mutans (S. mutans) in a planktonic suspension model. Suspensions of both strains were divided into 4 groups as follows: absence of C and L (control group: C-L-), with C and without L (C group: C+L-), absence of C with L (L group: C-L+) and presence of C and L (PDT group: C+L+). Three different concentrations of curcumin (0.75 mg/ml, 1.5 mg/ml and 3 mg/ml) and three light fluences of studied light source (24, 48 and 72 J cm(-2)) were tested. Aliquots of each studied group was plated in BHI agar and submitted to colony forming units counting (CFU/ml) and the data transformed into logarithmical scale. A high photoinactivation rate of more than 70% was verified to standard S. mutans strain submitted to PDT whereas the clinical isolate showed a lower sensitivity to all the associations of curcumin and LED. A slight bacterial reduction was verified to C+L- and C-L+, demonstrating no toxic effects to the isolated application of light and photosensitizer to both S. mutans strains tested. Photodynamic therapy using a combination of curcumin and blue LED presented a substantial antimicrobial effect on S. mutans standard strain in a planktonic suspension model with a less pronounced effect on its clinical isolate counterparts due to resistance to this alternative approach. Alternative antimicrobial approaches, as photodynamic therapy, should be encouraged due to optimal results against cariogenic bacteria aiming to prevent or treat dental caries.

  7. Antimicrobial susceptibility of clinical isolates of anaerobic bacteria in Ontario, 2010-2011.

    Science.gov (United States)

    Marchand-Austin, Alex; Rawte, Prasad; Toye, Baldwin; Jamieson, Frances B; Farrell, David J; Patel, Samir N

    2014-08-01

    The local epidemiology of antimicrobial susceptibility patterns in anaerobic bacteria is important in guiding the empiric treatment of infections. However, susceptibility data are very limited on anaerobic organisms, particularly among non-Bacteroides organisms. To determine susceptibility profiles of clinically-significant anaerobic bacteria in Ontario Canada, anaerobic isolates from sterile sites submitted to Public Health Ontario Laboratory (PHOL) for identification and susceptibility testing were included in this study. Using the E-test method, isolates were tested for various antimicrobials including, penicillin, cefoxitin, clindamycin, meropenem, piperacillin-tazobactam and metronidazole. The MIC results were interpreted based on guidelines published by Clinical and Laboratory Standards Institute. Of 2527 anaerobic isolates submitted to PHOL, 1412 were either from sterile sites or bronchial lavage, and underwent susceptibility testing. Among Bacteroides fragilis, 98.2%, 24.7%, 1.6%, and 1.2% were resistant to penicillin, clindamycin, piperacillin-tazobactam, and metronidazole, respectively. Clostridium perfringens was universally susceptible to penicillin, piperacillin-tazobactam, and meropenem, whereas 14.2% of other Clostridium spp. were resistant to penicillin. Among Gram-positive anaerobes, Actinomyces spp., Parvimonas micra and Propionibacterium spp. were universally susceptible to β-lactams. Eggerthella spp., Collinsella spp., and Eubacterium spp. showed variable resistance to penicillin. Among Gram-negative anaerobes, Fusobacterium spp., Prevotella spp., and Veillonella spp. showed high resistance to penicillin but were universally susceptible to meropenem and piperacillin-tazobactam. The detection of metronidazole resistant B. fragilis is concerning as occurrence of these isolates is extremely rare. These data highlight the importance of ongoing surveillance to provide clinically relevant information to clinicians for empiric management of

  8. Standardization and classification of In vitro biofilm formation by clinical isolates of Staphylococcus aureus

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    Ashish Kumar Singh

    2017-01-01

    Full Text Available Background: Staphylococcus aureus is Gram-positive bacterium commonly associated with nosocomial infections. The development of biofilm exhibiting drug resistance especially in foreign body associated infections has enabled the bacterium to draw considerable attention. However, till date, consensus guidelines for in vitro biofilm quantitation and categorization criterion for the bacterial isolates based on biofilm-forming capacity are lacking. Therefore, it was intended to standardize in vitro biofilm formation by clinical isolates of S. aureus and then to classify them on the basis of their biofilm-forming capacity. Materials and Methods: A study was conducted for biofilm quantitation by tissue culture plate (TCP assay employing 61 strains of S. aureus isolated from clinical samples during May 2015– December 2015 wherein several factors influencing the biofilm formation were optimized. Therefore, it was intended to propose a biofilm classification criteria based on the standard deviation multiples of the control differentiating them into non, low, medium, and high biofilm formers. Results: Brain-heart infusion broth was found to be more effective in biofilm formation compared to trypticase soy broth. Heat fixation was more effective than chemical fixation. Although, individually, glucose, sucrose, and sodium chloride (NaCl had no significant effect on biofilm formation, a statistically significant increase in absorbance was observed after using the supplement mix consisting of 222.2 mM glucose, 116.9 mM sucrose, and 1000 mM NaCl (P = 0.037. Conclusions: The present study puts forth a standardized in vitro TCP assay for biofilm biomass quantitation and categorization criteria for clinical isolates of S. aureus based on their biofilm-forming capacity. The proposed in vitro technique may be further evaluated for its usefulness in the management of persistent infections caused by the bacterium.

  9. Use of CHROMagar Candida for the presumptive identification of Candida species directly from clinical specimens in resource-limited settings

    Science.gov (United States)

    Nadeem, Sayyada Ghufrana; Hakim, Shazia Tabassum; Kazmi, Shahana Urooj

    2010-01-01

    Introduction Identification of yeast isolated from clinical specimens to the species level has become increasingly important. Ever-increasing numbers of immuno-suppressed patients, a widening range of recognized pathogens, and the discovery of resistance to antifungal drugs are contributing factors to this necessity. Material and methods A total of 487 yeast strains were studied for the primary isolation and presumptive identification, directly from clinical specimen. Efficacy of CHROMagar Candida has been evaluated with conventional methods including morphology on Corn meal–tween 80 agar and biochemical methods by using API 20 C AUX. Results The result of this study shows that CHROMagar Candida can easily identify three species of Candida on the basis of colonial color and morphology, and accurately differentiate between them i.e. Candida albicans, Candida tropicalis, and Candida krusei. The specificity and sensitivity of CHROMagar Candida for C. albicans calculated as 99%, for C. tropicalis calculated as 98%, and C. krusei it is 100%. Conclusion The data presented supports the use of CHROMagar Candida for the rapid identification of Candida species directly from clinical specimens in resource-limited settings, which could be very helpful in developing appropriate therapeutic strategy and management of patients. PMID:21483597

  10. Characterization of Staphylococcus caprae Clinical Isolates Involved in Human Bone and Joint Infections, Compared with Goat Mastitis Isolates.

    Science.gov (United States)

    d'Ersu, J; Aubin, G G; Mercier, P; Nicollet, P; Bémer, P; Corvec, S

    2016-01-01

    Staphylococcus caprae is an emerging microorganism in human bone and joint infections (BJI). The aim of this study is to describe the features of S. caprae isolates involved in BJI (H for human) compared with those of isolates recovered in goat mastitis (A for animal). Fourteen isolates of each origin were included. Identifications were performed using a Vitek 2 GP ID card, tuf gene sequencing, and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) Vitek MS. Molecular typing was carried out using pulsed-field gel electrophoresis (PFGE) and DiversiLab technology. The crystal violet method was used to determine biofilm-forming ability. Virulence factors were searched by PCR. Vitek MS technology provides an accurate identification for the two types of isolates compared to that of gold-standard sequencing (sensitivity, 96.4%), whereas the Vitek 2 GP ID card was more effective for H isolates. Molecular typing methods revealed two distinct lineages corresponding to the origin despite few overlaps: H and A. In our experimental conditions, no significant difference was observed in biofilm production ability between H and A isolates. Nine isolates (5 H isolates and 4 A isolates) behaved as weak producers while one A isolate was a strong producer. Concerning virulence factors, the autolysin atlC and the serine aspartate adhesin (sdrZ) genes were detected in 24 isolates (86%), whereas the lipase gene was always detected, except in one H isolate (96%). The ica operon was present in 23 isolates (82%). Fibrinogen-binding (fbe) or collagen-binding (cna) genes were not detected by using primers designed for Staphylococcus aureus or Staphylococcus epidermidis, even in low stringency conditions. Although S. caprae probably remains underestimated in human infections, further studies are needed to better understand the evolution and the adaptation of this species to its host. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  11. Clinical mastitis in dairy cattle in Ontario: frequency of occurrence and bacteriological isolates.

    Science.gov (United States)

    Sargeant, J M; Scott, H M; Leslie, K E; Ireland, M J; Bashiri, A

    1998-01-01

    The objective of this study was to describe the frequency of occurrence of clinical mastitis in dairy herds in Ontario. The study group consisted of 65 dairy farms involved in a 2-year observational study, which included recording all clinical mastitis cases and milk sampling of quarters with clinical mastitis. Lactational incidence risks of 9.8% for abnormal milk only, 8.2% for abnormal milk with a hard or swollen udder, and 4.4% for abnormal milk plus systemic signs of illness related to mastitis were calculated for 2840 cows and heifers. Overall, 19.8% of cows experienced one or more cases of clinical mastitis during location. Teat injuries occurred in 2.1% of lactations. Standard bacteriology was performed on pretreatment milk samples from 834 cows with clinical mastitis. The bacteria isolated were Staphylococcus aureus (6.7%), Streptococcus agalactiae (0.7%), other Streptococcus spp. (14.1%), coliforms (17.2%), gram-positive bacilli (5.5%), Corynebacterium bovis (1.7%), and other Staphylococcus spp. (28.7%). There was no growth in 17.7% of samples, and 8.3% of samples were contaminated. Clinical mastitis is a common disease in dairy cows in Ontario; approximately 1 in 5 cow lactations have at lease one episode of clinical mastitis. There is, however, considerable variation in the incidence of clinical mastitis among farms. The majority of 1st cases of clinical mastitis occur early in lactation, and the risk of clinical mastitis increases with increasing parity. Environmental, contagious, and minor pathogens were all associated with cases of clinical mastitis.

  12. Tenofovir alafenamide demonstrates broad cross-genotype activity against wild-type HBV clinical isolates and maintains susceptibility to drug-resistant HBV isolates in vitro.

    Science.gov (United States)

    Liu, Yang; Miller, Michael D; Kitrinos, Kathryn M

    2017-03-01

    Tenofovir alafenamide (TAF) is a novel prodrug of tenofovir (TFV). This study evaluated the antiviral activity of TAF against wild-type genotype A-H HBV clinical isolates as well as adefovir-resistant, lamivudine-resistant, and entecavir-resistant HBV isolates. Full length HBV genomes or the polymerase/reverse transcriptase (pol/RT) region from treatment-naïve patients infected with HBV genotypes A-H were amplified and cloned into an expression vector under the control of a CMV promoter. In addition, 11 drug resistant HBV constructs were created by site-directed mutagenesis of a full length genotype D construct. Activity of TAF was measured by transfection of each construct into HepG2 cells and assessment of HBV DNA levels following treatment across a range of TAF concentrations. TAF activity in vitro was similar against wild-type genotype A-H HBV clinical isolates. All lamivudine- and entecavir-resistant isolates and 4/5 adefovir-resistant isolates were found to be sensitive to inhibition by TAF in vitro as compared to the wild-type isolate. The adefovir-resistant isolate rtA181V + rtN236T exhibited low-level reduced susceptibility to TAF. TAF is similarly active in vitro against wild-type genotype A-H HBV clinical isolates. The TAF sensitivity results for all drug-resistant isolates are consistent with what has been observed with the parent drug TFV. The in vitro cell-based HBV phenotyping assay results support the use of TAF in treatment of HBV infected subjects with diverse HBV genotypes, in both treatment-naive and treatment-experienced HBV infected patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. PREVALENCE OF ACINETOBACTER BAUMANNII ISOLATED FROM CLINICAL SPECIMENS IN ADAM MALIK HOSPITAL

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    Evita Mayasari

    2014-05-01

    Full Text Available AbstrakAcinetobacter baumannii merupakan spesies Acinetobacter spp. tersering diisolasi darimanusia, dan lebih sering dijumpai pada infeksi nosokomial dibandingkan dengan infeksi dikomunitas. Eksistensi bakteri ini di lingkungan terkait dengan keragaman reservoir, kemampuanmemperoleh gen pembawa sifat resisten antimikroba, dan sifat resisten terhadap pengeringan.Infeksi disebabkan strain A.baumannii yang resisten terhadap banyak antibiotik tidak mudahdikendalikan dan menjadi permasalahan di berbagai negara. Penelitian ini bertujuan untukmengetahui prevalensi A.baumannii dari spesimen klinis di instalasi mikrobiologi klinik RSUPHaji Adam Malik serta pola kepekaannya terhadap berbagai antibiotik. Identifikasi dan ujikepekaan menggunakan mesin otomatis Vitek 2 dengan Advanced Expert System (AES.Penelitian ini menemukan 644/3693 (17,44% isolat A.baumannii dari berbagai spesimen klinis.A.baumannii paling banyak diisolasi dari spesimen dahak. Penelitian ini menemukan 147/644(23% bahwa isolat carbapenem-resistent A.baumannii (imipenem dan meropenem. Sebagianbesar isolat sensitif terhadap colistin, amikacin dan tigecycline. Prevalensi A.baumanni yangditemukan pada penelitian ini adalah rendah namun resistensinya tinggi terhadap antibiotikterutama golongan penicillin, cephalosporin dan fluoroquinolon.AbstractAcinetobacter baumannii is the most frequent species of Acinetobacter spp. isolated fromhumans and more common in nosocomial infection than it is in community acquired infection.A.baumannii existence in environment is associated with the diversity of its reservoirs, itscapacity to accumulate genes of antimicrobial resistence, and its resistence to desiccation.Infection of Multidrug resistent (MDR strain of A.baumannii is not easy to manage and it hasbecome a problem in many countries. The aim of this retrospective study was to investigatethe prevalence of A.baumannii from routine clinical specimens sent to clinical microbiologylaboratory RSUP HAM

  14. Spoligotyping of clinical Mycobacterium tuberculosis isolates from the state of Minas Gerais, Brazil

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    Silvana Spíndola de Miranda

    2011-05-01

    Full Text Available We performed spoligotyping on 114 strains of the Mycobacterium tuberculosis (Mtb complex that had been isolated from patients in Minas Gerais Health Units during 2004. A total of 82/114 (72% clinical isolates were clustered and 32/114 (28% were unique. Seven shared types containing nine strains were newly created. A total of nine patterns corresponded to unreported orphan strains, as evaluated against all of the strains recorded in the SITVIT2 proprietary database in the Institut Pasteur de la Guadeloupe. The major clades were composed of isolates that belong to the following genotypes: Latin-America and Mediterranean (63/114, 55.3% (the ill-defined T superfamily (12/114, 10.5%, Haarlem (8/114, 7%, X clade (6/114, 5.3%, S clade (3/114, 2.6% and the East-African Indian and Manu types, each with 1/114 (0.9% isolates. A considerable number of strains (n = 20, 17.5% showed patterns that did not fall within any of the previously described major clades. We conclude the bulk of tuberculosis (TB (92/114, 80.7% in our location is recent evolutionary strains that belong to the principal genetic groups 2/3. Further studies on epidemiology of TB are required to understand Mtb biodiversity and TB transmission in this region.

  15. Detection of colistin sensitivity in clinical isolates of Acinetobacter baumannii in Iran

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    Bahareh Vakili

    2014-01-01

    Full Text Available Background: Nosocomial infection caused by Acinetobacter baumannii has emerged as a serious problem world-wide. Finding the suitable drug is an important priority. The aim of this study was to determine colistin (polymyxin E resistance in clinical isolates of A. baumannii from intensive care units (ICUs of Al Zahra Hospital. Materials and Methods: Sixty isolates of A. baumannii from patients hospitalized in ICU (Al Zahra Hospital, Isfahan University of Medical Sciences [IUMS] were studied. All isolates of A. baumannii were tested for colistin susceptibility by Eopsilometer test (E-test. Results: Of the 60 isolates 57, (95% were multidrug resistant (MDR and 76.6% (46/60 were highly resistant. The rate of colistin resistant with the E-test method was 11.6% (7/60. Conclusion: As the frequency of resistance to colistin is low, it can be used as an easily available drug for treatment of MDR A. baumannii strains, which are susceptible to colistin.

  16. Virulence factors and clinical patterns of hypermucoviscous Klebsiella pneumoniae isolated from urine.

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    Kim, Youn Jeong; Kim, Sang Il; Kim, Yang Ree; Wie, Seong Heon; Lee, Hae Kyung; Kim, Soo-Young; Park, Yeon-Joon

    2017-03-01

    Klebsiella pneumoniae with hypermucoviscosity (HM) phenotype is generally more virulent than HM-negative strains. The aim of this study was to investigate the prevalence of HM phenotype among urinary isolates and to compare the virulence factors, antimicrobial susceptibility patterns and clinical characteristics of HM-positive and -negative K. pneumoniae isolated from urine of hospitalized patients. From June to October 2013, a total of 81 non-repetitive K. pneumoniae strains were isolated from urine. HM phenotype was determined by a string test. The K1 and K2 genotypes, the allS, kfu, rmpA, rmpA2 and wabG, aerobactin gene were detected by polymerase chain reaction. Of the 81 K. pneumoniae isolates, 12.3% produced a positive string test. The aerobactin (80.0%[8/10] vs. 15.5%[11/71], p = .0001), allS (40.0%[4/10] vs. 9.9%[7/71], p = .009), rmpA (70.0%[7/10] vs. 14.1%[10/71], p = .0001) and rmpA2 (60.0%[6/10] vs. 16.9%[12/71], p = .002) genes were more prevalent in HM positive than in HM negative strains. The K1 (20.0%[2/10) vs. 8.5%[6/71

  17. Identification of virulence genes carried by bacteriophages obtained from clinically isolated methicillin-resistant Staphylococcus aureus.

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    Karasartova, Djursun; Cavusoglu, Zeynep Burcin; Turegun, Buse; Ozsan, Murat T; Şahin, Fikret

    2016-12-01

    Bacteriophages play an important role in the pathogenicity of Staphylococcus aureus (S. aureus) either by carrying accessory virulence factors or several superantigens. Despite their importance, there are not many studies showing the actual distribution of the virulence genes carried by the prophages obtained from the clinically isolated Staphylococcus. In this study, we investigated prophages obtained from methicillin-resistant S. aureus (MRSA) strains isolated from hospital- and community-associated (HA-CA) infections for the virulence factors. In the study, 43 phages isolated from 48 MRSA were investigated for carrying toxin genes including the sak, eta, lukF-PV, sea, selp, sek, seg, seq chp, and scn virulence genes using polymerase chain reaction (PCR) and Southern blot. Restriction fragment length polymorphism was used to analyze phage genomes to investigate the relationship between the phage profiles and the toxin genes' presence. MRSA strains isolated from HA infections tended to have higher prophage presence than the MRSA strains obtained from the CA infections (97% and 67%, respectively). The study showed that all the phages with the exception of one phage contained one or more virulence genes in their genomes with different combinations. The most common toxin genes found were sea (83%) followed by sek (77%) and seq (64%). The study indicates that prophages encode a significant proportion of MRSA virulence factors.

  18. Aminoglycosides resistance in clinical isolates of Staphylococcus aureus from a University Hospital in Bialystok, Poland.

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    Katarzyna Kaczyńska

    2008-06-01

    Full Text Available Staphylococcus aureus obtained from a University Hospital in Poland were characterized in relation to resistance to aminoglycoside antibiotics and the distribution of the genes encoding the most clinically relevant aminoglycoside modifying enzymes (AMEs. Of a total of 118 S. aureus, 45 (38.1% isolates were found to be resistant to at least one of the tested antibiotics. All aminoglycoside resistant isolates except one 44 (97.8% were resistant to kanamycin. The majority of strains 37 (82.2% and 32 (71.1% expressed resistance to neomycin and tobramycin, respectively. Eleven strains (24.4% were resistant to gentamicin or amikacin. All S. aureus strains were sensitive to netilmicin. The most prevalent resistance gene was aac(6'-Ie+aph(2' found in 13 (28.9% strains and 12 (26.7% isolates carried ant(4'-Ia gene, whilst aph(3'-IIIa gene was detected in only 7 (15.6% isolates. Additionally, the ant(6-Ia and str genes were detected in 14 (31.1% and 2 (4.4% strains, respectively. Ten (22.2% strains resistant to amikacin, tobramycin, kanamycin or neomycin did not harbor any of the above-noted genes.

  19. Antibacterial Activity of Twenty Iranian Plant Extracts Against Clinical Isolates of Helicobacter pylori

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    Farahnaz Nariman

    2009-06-01

    Full Text Available Objective(sDue to increasing emergence of drug-resistance in Helicobacter pylori isolates, traditional plants arepotentially valuable sources of novel anti-H. pylori agents. In this research, anti-H. pylori activity of theorganic extracts of twenty native Iranian plants was determined against ten clinical isolates of H. pylori.Materials and MethodsDisc diffusion was used to determine the biological activity of 20 plant extracts as well as 8 antibioticscommonly used to treat H. pylori infections. Minimum inhibitory concentrations were also measured by tubeand agar dilution methods for the biologically active plant extracts.ResultsOf the twenty plant extracts analyzed, sixteen exhibited good anti-H. pylori activity, using disc diffusion.The ten most active extracts were Carum bulbocastanum, Carum carvi, Mentha longifolia, Saliva limbata,Saliva sclarea, Ziziphora clinopodioides, Thymus caramanicus, Glycyrrhiza glabra, Xanthium brasilicumand Trachyspermum copticum. Minimum inhibitory concentrations measured for the 10 biologically activeplant extracts were within the range of 31.25 to 500 μg/ml.ConclusionAmong the ten plant extracts effective against H. pylori clinical isolates, Carum carvi, Xanthium brasilicumand Trachyspermum copticum showed the highest activity.Keywords: Anti-Helicobacter pylori, Iranian plants, Organic extracts

  20. Evaluation of different detection methods of biofilm formation in the clinical isolates

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    Afreenish Hassan

    Full Text Available BACKGROUND: Microorganisms growing in a biofilm are associated with chronic and recurrent human infections and are highly resistant to antimicrobial agents. There are various methods to detect biofilm production like Tissue Culture Plate (TCP, Tube method (TM, Congo Red Agar method (CRA, bioluminescent assay, piezoelectric sensors, and fluorescent microscopic examination. OBJECTIVE: This study was conducted to compare three methods for the detection of biofilms. METHOD: The study was carried out at the Department of Microbiology, Army Medical College, National University of Sciences and Technology, Pakistan, from January 2010 to June 2010. A total of 110 clinical isolates were subjected to biofilm detection methods. Isolates were identified by standard microbiological procedures. Biofilm detection was tested by TCP, TM and CRA. Antibiotic susceptibility test of biofilm producing bacteria was performed by using the Kirby-Bauer disc diffusion technique according to CLSI guidelines. RESULTS: The TCP method was considered to be superior to TM and CRA. From the total of 110 clinical isolates, TCP method detected 22.7% as high, 41% moderate and 36.3% as weak or non-biofilm producers. We have observed higher antibiotic resistance in biofilm producing bacteria than non-biofilm producers. CONCLUSION: We can conclude from our study that the TCP method is a more quantitative and reliable method for the detection of biofilm forming microorganisms as compared to TM and CRA methods, and it can be recommended as a general screening method for detection of biofilm producing bacteria in laboratories.

  1. Molecular detection of aminoglycoside-modifying enzyme genes in Acinetobacter baumannii clinical isolates.

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    Heidary, Mohsen; Salimi Chirani, Alireza; Khoshnood, Saeed; Eslami, Gita; Atyabi, Seyyed Mohammad; Nazem, Habibollah; Fazilati, Mohammad; Hashemi, Ali; Soleimani, Saleh

    2017-06-01

    Acinetobacter baumannii is a major opportunistic pathogen in healthcare settings worldwide. In Iran, there are only few reports on the prevalence of aminoglycoside resistance genes among A. baumannii isolates. The aim of this study was to investigate the existence of aminoglycoside-modifying enzyme (AME) genes from A. baumannii strains collected at a university teaching hospital in Iran. One hundred A. baumannii strains were collected between 2014 and 2015 from hospitalized patients at Loghman Hakim Hospital, Tehran, Iran. Antimicrobial susceptibility was determined by disk diffusion method according to the Clinical and Laboratory Standards Institute recommendations. The DNA was extracted using a kit obtained from Bioneer Co. (Korea) and was used as a template for polymerase chain reaction. The most active antimicrobial agent against these strains was colistin. The rate of extended-spectrum cephalosporin resistance was 97%. The aadA1, aadB, aac(6')-Ib, and aac(3)-IIa genes were found in 85%, 77%, 72%, and 68% of A. baumannii isolates, respectively. This study showed a high prevalence rate of AME genes in A. baumannii. This prevalence rate has explained that further aminoglycoside resistance genes may have role in the resistance of clinical isolates of A. baumannii. Therefore, control and treatment of serious infections caused by this opportunistic pathogen should be given more consideration.

  2. First isolation of methicillin-resistant Staphylococcus aureus from pigs’ clinical samples in Serbia

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    Milenko Zutic

    2012-01-01

    Full Text Available Methicillin-resistant Staphylococcus aureus is a highly important human pathogen that is also a significant concern in veterinary medicine. Despite the high prevalence of colonization, clinical infections with methicillin-resistant Staphylococcus aureus appear to be rare in pigs. Methicillin-resistant Staphylococcus aureus was isolated from a sow with endometritis and her five piglets with dermatitis originating from a Serbian farm. Identification of the strains was done by automated system and confirmed by polymerase chain reaction for mecA and nuc genes. Detection of Staphylococcal Cassette Chromosome mec type was performed by multiplex polymerase chain reaction. Antimicrobial susceptibility testing on erythromycin, clindamycin, gentamicin, kanamycin, tobramycin, ciprofloxacin, tetracycline, trimethoprim/sulfamethoxazole and vancomycin was done by disc diffusion method. Six isolated strains from the infected sow and her piglets showed resistance only to tetracycline beside resistance to all beta-lactam antibiotics. In the tested methicillin-resistant Staphylococcus aureus isolates, Staphylococcal Cassette Chromosome mec type V was present. To our knowledge, this finding is the first documented detection of methicillin-resistant Staphylococcus aureus from pigs’ clinical samples in Serbia. The results of our study indicate the emergence of methicillin-resistant Staphylococcus aureus in a pig farm in Serbia highlighting the threat of this antibiotic-resistant microorganism as a pathogen causing both animal and human infections.

  3. Comparative "-omics" in Mycoplasma pneumoniae Clinical Isolates Reveals Key Virulence Factors.

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    Maria Lluch-Senar

    Full Text Available The human respiratory tract pathogen M. pneumoniae is one of the best characterized minimal bacterium. Until now, two main groups of clinical isolates of this bacterium have been described (types 1 and 2, differing in the sequence of the P1 adhesin gene. Here, we have sequenced the genomes of 23 clinical isolates of M. pneumoniae. Studying SNPs, non-synonymous mutations, indels and genome rearrangements of these 23 strains and 4 previously sequenced ones, has revealed new subclasses in the two main groups, some of them being associated with the country of isolation. Integrative analysis of in vitro gene essentiality and mutation rates enabled the identification of several putative virulence factors and antigenic proteins; revealing recombination machinery, glycerol metabolism and peroxide production as possible factors in the genetics and physiology of these pathogenic strains. Additionally, the transcriptomes and proteomes of two representative strains, one from each of the two main groups, have been characterized to evaluate the impact of mutations on RNA and proteins levels. This study has revealed that type 2 strains show higher expression levels of CARDS toxin, a protein recently shown to be one of the major factors of inflammation. Thus, we propose that type 2 strains could be more toxigenic than type 1 strains of M. pneumoniae.

  4. Identification of Highly Expressed Plasmodium Vivax Proteins from Clinical Isolates Using Proteomics.

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    Venkatesh, Apoorva; Lahiri, Anwesha; Reddy, Panga Jaipal; Shastri, Jayanthi; Bankar, Sheetal; Patankar, Swati; Srivastava, Sanjeeva

    2017-08-25

    Plasmodium vivax is the most geographically widespread species responsible for malaria in humans. Our study focused on identifying highly expressed parasite proteins using a shotgun proteomics approach. Parasites (P. vivax) are isolated from seven patient samples using saponin lysis. Protein extracts from these parasites are processed and subjected to LC-MS/MS analysis. An overall proteome coverage of 605 P. vivax proteins along with 1670 human host proteins are obtained upon combining the data from LC-MS/MS runs. While a major proportion of the P. vivax proteins are either hypothetical or involved in basic cellular activities, few proteins such as tryptophan-rich antigen (Pv-fam-a; PVX_090265), Pv-fam-d protein (PVX_101520), Plasmodium exported protein (PVX_003545), Pvstp1 (PVX_094303) and hypothetical protein (PVX_083555) are detected in more than 80% of the clinical isolates and found to be unique to P. vivax without orthologs in P. falciparum. Our proteomics study on individual parasite isolates reveals highly expressed P. vivax proteins, few of which may be good candidates for vivax malaria diagnosis due to their abundance and absence in P. falciparum. This study represents the first step towards the identification of biomarkers for P. vivax malaria. In future, their clinical diagnostic values must be explored and validated on large patient cohorts. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Clinical Significance and Characterization of Streptococcus tigurinus Isolates in an Adult Population.

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    Bourassa, Lori; Clarridge, J E

    2015-11-01

    Streptococcus tigurinus is a newly described member of the Streptococcus mitis group. Due to the difficulty in distinguishing viridans group streptococci (VGS) by phenotype, analysis of 16S rRNA sequences is necessary for the accurate identification of most species. Through a laboratory policy of analyzing all clinically significant isolates from the VGS group by16S rRNA gene sequencing, we identified 14 S. tigurinus isolates from 11 patients. The Vitek 2 system most commonly gave an excellent rating to an incorrect identification (e.g., Streptococcus mitis), as did matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) (e.g., Streptococcus oralis). S. tigurinus strains were recovered from numerous body sites, including the blood, peritoneal fluid, bone, synovial fluid, a perianal abscess, and an arm wound. Retrospective chart review indicated that most isolates were clinically significant, with bacteremia (n = 5), soft tissue infections (n = 3) osteomyelitis (n = 2), infected joint prosthesis (n = 2), and peritonitis (n = 2) being the most common, thus expanding the spectrum of disease associated with S. tigurinus. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Remobilization of Sleeping Beauty transposons in the germline of Xenopus tropicalis

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    Yergeau Donald A

    2011-11-01

    Full Text Available Abstract Background The Sleeping Beauty (SB transposon system has been used for germline transgenesis of the diploid frog, Xenopus tropicalis. Injecting one-cell embryos with plasmid DNA harboring an SB transposon substrate together with mRNA encoding the SB transposase enzyme resulted in non-canonical integration of small-order concatemers of the transposon. Here, we demonstrate that SB transposons stably integrated into the frog genome are effective substrates for remobilization. Results Transgenic frogs that express the SB10 transposase were bred with SB transposon-harboring animals to yield double-transgenic 'hopper' frogs. Remobilization events were observed in the progeny of the hopper frogs and were verified by Southern blot analysis and cloning of the novel integrations sites. Unlike the co-injection method used to generate founder lines, transgenic remobilization resulted in canonical transposition of the SB transposons. The remobilized SB transposons frequently integrated near the site of the donor locus; approximately 80% re-integrated with 3 Mb of the donor locus, a phenomenon known as 'local hopping'. Conclusions In this study, we demonstrate that SB transposons integrated into the X. tropicalis genome are effective substrates for excision and re-integration, and that the remobilized transposons are transmitted through the germline. This is an important step in the development of large-scale transposon-mediated gene- and enhancer-trap strategies in this highly tractable developmental model system.

  7. Construction of genetically engineered Candida tropicalis for conversion of L-arabinose to L-ribulose.

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    Yeo, In-Seok; Shim, Woo-Yong; Kim, Jung Hoe

    2018-01-30

    For the biological production of L-ribulose, conversion by enzymes or resting cells has been investigated. However, expensive or concentrated substrates, an additional purification step to remove borate and the requirement for cell cultivation and harvest steps before utilization of resting cells make the production process complex and unfavorable. Microbial fermentation may help overcome these limitations. In this study, we constructed a genetically engineered Candida tropicalis strain to produce L-ribulose by fermentation with a glucose/L-arabinose mixture. For the uptake of L-arabinose as a substrate and conversion of L-arabinose to L-ribulose, two heterologous genes coding for L-arabinose transporter and L-arabinose isomerase, were constitutively expressed in C. tropicalis under the GAPDH promoter. The Arabidopsis thaliana-originated L-arabinose transporter gene (STP2)-expressing strain exhibited a high L-arabinose uptake rate of 0.103 g/g cell/h and the expression of L-arabinose isomerase from Lactobacillus sakei 23K showed 30% of conversion (9 g/L) from 30 g/L of L-arabinose. This genetically engineered strain can be used for L-ribulose production by fermentation using mixed sugars of glucose and L-arabinose. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Highly efficient bi-allelic mutation rates using TALENs in Xenopus tropicalis

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    Shoko Ishibashi

    2012-10-01

    In the past decade, Xenopus tropicalis has emerged as a powerful new amphibian genetic model system, which offers all of the experimental advantages of its larger cousin, Xenopus laevis. Here we investigated the efficiency of transcription activator-like effector nucleases (TALENs for generating targeted mutations in endogenous genes in X. tropicalis. For our analysis we targeted the tyrosinase (oculocutaneous albinism IA (tyr gene, which is required for the production of skin pigments, such as melanin. We injected mRNA encoding TALENs targeting the first exon of the tyr gene into two-cell-stage embryos. Surprisingly, we found that over 90% of the founder animals developed either partial or full albinism, suggesting that the TALENs induced bi-allelic mutations in the tyr gene at very high frequency in the F0 animals. Furthermore, mutations tyr gene were efficiently transmitted into the F1 progeny, as evidenced by the generation of albino offspring. These findings have far reaching implications in our quest to develop efficient reverse genetic approaches in this emerging amphibian model.

  9. Ouro proteins are not essential to tail regression during Xenopus tropicalis metamorphosis.

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    Nakai, Yuya; Nakajima, Keisuke; Robert, Jacques; Yaoita, Yoshio

    2016-03-01

    Tail regression is one of the most prominent transformations observed during anuran metamorphosis. A tadpole tail that is twice as long as the tadpole trunk nearly disappears within 3 days in Xenopus tropicalis. Several years ago, it was proposed that this phenomenon is driven by an immunological rejection of larval-skin-specific antigens, Ouro proteins. We generated ouro-knockout tadpoles using the TALEN method to reexamine this immunological rejection model. Both the ouro1- and ouro2-knockout tadpoles expressed a very low level of mRNA transcribed from a targeted ouro gene, an undetectable level of Ouro protein encoded by a target gene and a scarcely detectable level of the other Ouro protein from the untargeted ouro gene in tail skin. Furthermore, congenital athymic frogs were produced by Foxn1 gene modification. Flow cytometry analysis showed that mutant frogs lacked splenic CD8(+) T cells, which play a major role in cytotoxic reaction. Furthermore, T-cell-dependent skin allograft rejection was dramatically impaired in mutant frogs. None of the knockout tadpoles showed any significant delay in the process of tail shortening during the climax of metamorphosis, which shows that Ouro proteins are not essential to tail regression at least in Xenopus tropicalis and argues against the immunological rejection model. © 2016 The Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  10. TALEN-mediated apc mutation in Xenopus tropicalis phenocopies familial adenomatous polyposis

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    Van Nieuwenhuysen, Tom; Naert, Thomas; Tran, Hong Thi; Van Imschoot, Griet; Geurs, Sarah; Sanders, Ellen; Creytens, David; Van Roy, Frans; Vleminckx, Kris

    2015-01-01

    Truncating mutations in the tumor suppressor gene adenomatous polyposis coli (APC) are the initiating step in the vast majority of sporadic colorectal cancers, and they underlie familial adenomatous polyposis (FAP) syndromes. Modeling of APC- driven tumor formation in the mouse has contributed substantially to our mechanistic understanding of the associated disease, but additional models are needed to explore therapeutic opportunities and overcome current limitations of mouse models. We report on a novel and penetrant genetic cancer model in Xenopus tropicalis, an aquatic tetrapod vertebrate with external development, diploid genome and short life cycle. Tadpoles and froglets derived from embryos injected with TAL effector nucleases targeting the apc gene rapidly developed intestinal hyperplasia and other neoplasms observed in FAP patients, including desmoid tumors and medulloblastomas. Bi-allelic apc mutations causing frame shifts were detected in the tumors, which displayed activation of the Wnt/β-catenin pathway and showed increased cellular proliferation. We further demonstrate that simultaneous double bi-allelic mutation of apc and a non-relevant gene is possible in the neoplasias, opening the door for identification and characterization of effector or modifier genes in tumors expressing truncated apc. Our results demonstrate the power of modeling human cancer in Xenopus tropicalis using mosaic TALEN-mediated bi-allelic gene disruption. PMID:26097888

  11. Bioconversion Studies of Methyl Laurate to Dodecanedioic Acid using a Wild-type of Candida tropicalis

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    Akmalina Rifkah

    2018-01-01

    Full Text Available Production of dodecanedioic acid (DDDA, a platform chemical used as raw material for various commodities and polymers, has been studied through a biological process. This process was conducted by using a wild-type of Candida tropicalis which can be obtained easily from natural resources. The aim of this research was to study the characteristics of DDDA production from methyl laurate through batch fermentation process. Growth phase was carried out for 20 h, as the beginning of fermentation, then continued to conversion phase for 5 until 6 days. Utilization of methyl laurate and production of DDDA were analysed using gas chromatography, which proved the ability of C. tropicalis in assimilating methyl laurate to convert it become DDDA. The highest value of cells yield (Yx/s and DDDA yield (Yp/s successfully obtained were 0.86 g cells/g methyl laurate and 0.20 g DDDA/g methyl laurate, respectively. This study also showed the possibility of fermentation products accumulation as intermediate, or accumulation of DDDA inside the cells. Thus, this study can be applied as an alternative in addition to the use of mutant microorganism in producing DDDA.

  12. Nitric Acid-Treated Carbon Fibers with Enhanced Hydrophilicity for Candida tropicalis Immobilization in Xylitol Fermentation

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    Le Wang

    2016-03-01

    Full Text Available Nitric acid (HNO3-treated carbon fiber (CF rich in hydrophilic groups was applied as a cell-immobilized carrier for xylitol fermentation. Using scanning electron microscopy, we characterized the morphology of the HNO3-treated CF. Additionally, we evaluated the immobilized efficiency (IE of Candida tropicalis and xylitol fermentation yield by investigating the surface properties of nitric acid treated CF, specifically, the acidic group content, zero charge point, degree of moisture and contact angle. We found that adhesion is the major mechanism for cell immobilization and that it is greatly affected by the hydrophilic–hydrophilic surface properties. In our experiments, we found 3 hto be the optimal time for treating CF with nitric acid, resulting in an improved IE of Candida tropicalis of 0.98 g∙g−1 and the highest xylitol yield and volumetric productivity (70.13% and 1.22 g∙L−1∙h−1, respectively. The HNO3-treated CF represents a promising method for preparing biocompatible biocarriers for multi-batch fermentation.

  13. Identification and characterization of phenol hydroxylase from phenol-degrading Candida tropicalis strain JH8.

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    Long, Yan; Yang, Sheng; Xie, Zhixiong; Cheng, Li

    2014-09-01

    The gene phhY encoding phenol hydroxylase from Candida tropicalis JH8 was cloned, sequenced, and expressed in Escherichia coli. The gene phhY contained an open reading frame of 2130 bp encoding a polypeptide of 709 amino acid residues. From its sequence analysis, it is a member of a family of flavin-containing aromatic hydroxylases and shares 41% amino acid identity with phenol hydroxylase from Trichosporon cutaneum. The recombinant phenol hydroxylase exists as a homotetramer structure with a native molecular mass of 320 kDa. Recombinant phenol hydroxylase was insensitive to pH treatment; its optimum pH was at 7.6. The optimum temperature for the enzyme was 30 °C, and its activity was rapidly lost at temperatures above 60 °C. Under the optimal conditions with phenol as substrate, the K(m) and V(max) of recombinant phenol hydroxylase were 0.21 mmol·L(-1) and 0.077 μmol·L(-1)·min(-1), respectively. This is the first paper presenting the cloning and expression in E. coli of the phenol hydroxylase gene from C. tropicalis and the characterization of the recombinant phenol hydroxylase.

  14. Carbapenem-resistant and cephalosporin-susceptible: a worrisome phenotype among Pseudomonas aeruginosa clinical isolates in Brazil

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    Eloiza Helena Campana

    2017-01-01

    Full Text Available The mechanisms involved in the uncommon resistance phenotype, carbapenem resistance and broad-spectrum cephalosporin susceptibility, were investigated in 25 Pseudomonas aeruginosa clinical isolates that exhibited this phenotype, which were recovered from three different hospitals located in São Paulo, Brazil. The antimicrobial susceptibility profile was determined by CLSI broth microdilution. β-lactamase-encoding genes were investigated by PCR followed by DNA sequencing. Carbapenem hydrolysis activity was investigated by spectrophotometer and MALDI-TOF assays. The mRNA transcription level of oprD was assessed by qRT-PCR and the outer membrane proteins profile was evaluated by SDS-PAGE. Genetic relationship among P. aeruginosa isolates was assessed by PFGE. Carbapenems hydrolysis was not detected by carbapenemase assay in the carbapenem-resistant and cephalosporin-susceptible P. aueruginosa clinical isolates. OprD decreased expression was observed in all P. aeruginosa isolates by qRT-PCR. The outer membrane protein profile by SDS-PAGE suggested a change in the expression of the 46 kDa porin that could correspond to OprD porin. The isolates were clustered into 17 genotypes without predominance of a specific PFGE pattern. These results emphasize the involvement of multiple chromosomal mechanisms in carbapenem-resistance among clinical isolates of P. aeruginosa, alert for adaptation of P. aeruginosa clinical isolates under antimicrobial selective pressure and make aware of the emergence of an uncommon phenotype among P. aeruginosa clinical isolates.

  15. Enhancement of antibiotic activity by efflux inhibitors against multidrug resistant Mycobacterium tuberculosis clinical isolates from Brazil

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    Tatiane eCoelho

    2015-04-01

    Full Text Available Drug resistant tuberculosis continues to increase and new approaches for its treatment are necessary. The identification of M. tuberculosis clinical isolates presenting efflux as part of their resistant phenotype has a major impact in tuberculosis treatment. In this work, we used a checkerboard procedure combined with the tetrazolium microplate-based assay (TEMA to study single combinations between antituberculosis drugs and efflux inhibitors (EIs against multidrug resistant M. tuberculosis clinical isolates using the fully susceptible strain H37Rv as reference. Efflux activity was studied on a real-time basis by a fluorometric method that uses ethidium bromide as efflux substrate. Quantification of efflux pump genes mRNA transcriptional levels were performed by RT-qPCR. The fractional inhibitory concentrations (FIC indicated synergistic activity for the interactions between isoniazid, rifampicin, amikacin, ofloxacin, and ethidium bromide plus the EIs verapamil, thioridazine and chlorpromazine. The FICs ranged from 0.25, indicating a four-fold reduction on the MICs, to 0.015, 64-fold reduction. The detection of active efflux by real-time fluorometry showed that all strains presented intrinsic efflux activity that contributes to the overall resistance which can be inhibited in the presence of the EIs. The quantification of the mRNA levels of the most important efflux pump genes on these strains shows that they are intrinsically predisposed to expel toxic compounds as the exposure to subinhibitory concentrations of antibiotics were not necessary to increase the pump mRNA levels when compared with the non-exposed counterpart. The results obtained in this study confirm that the intrinsic efflux activity contributes to the overall resistance in multidrug resistant clinical isolates of M. tuberculosis and that the inhibition of efflux pumps by the EIs can enhance the clinical effect of antibiotics that are their substrates.

  16. Antibiotic susceptibility of periodontal Streptococcus constellatus and Streptococcus intermedius clinical isolates.

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    Rams, Thomas E; Feik, Diane; Mortensen, Joel E; Degener, John E; van Winkelhoff, Arie J

    2014-12-01

    Streptococcus constellatus and Streptococcus intermedius in subgingival dental plaque biofilms may contribute to forms of periodontitis that resist treatment with conventional mechanical root debridement/surgical procedures and may additionally participate in some extraoral infections. Because systemic antibiotics are often used in these clinical situations, and little is known of the antibiotic susceptibility of subgingival isolates of these two bacterial species, this study determined the in vitro susceptibility to six antibiotics of fresh S. constellatus and S. intermedius clinical isolates from human periodontitis lesions. A total of 33 S. constellatus and 17 S. intermedius subgingival strains, each recovered from separate patients with severe chronic periodontitis (n = 50) before treatment, were subjected to antibiotic gradient strip susceptibility testing with amoxicillin, azithromycin, clindamycin, ciprofloxacin, and doxycycline on blood-supplemented Mueller-Hinton agar and to the inhibitory effects of metronidazole at 16 mg/L in an enriched Brucella blood agar dilution assay. Clinical and Laboratory Standards Institute and European Committee on Antimicrobial Susceptibility Testing interpretative standards were used to assess the results. Clindamycin was the most active antibiotic against S. constellatus (minimum inhibitory concentration at 90% [MIC90] 0.25 mg/L), and amoxicillin was most active against S. intermedius (MIC90 0.125 mg/L). A total of 30% of the S. constellatus and S. intermedius clinical isolates were resistant in vitro to doxycycline, 98% were only intermediate in susceptibility to ciprofloxacin, and 90% were resistant to metronidazole at 16 mg/L. Subgingival S. constellatus and S. intermedius exhibited variable antibiotic susceptibility profiles, potentially complicating empirical selection of periodontitis antibiotic therapy in patients who are species positive.

  17. First report of NDM-1-producing clinical isolate of Leclercia adecarboxylata in Spain.

    Science.gov (United States)

    Riazzo, Cristina; López-Cerero, Lorena; Rojo-Martín, María Dolores; Hoyos-Mallecot, Yannick; Fernández-Cuenca, Felipe; Martín-Ruíz, Jose Luis; Pascual-Hernández, Álvaro; Naas, Thierry; Navarro-Marí, Jose María

    2017-07-01

    We describe the case of NDM-1-producing Leclercia adecarboxylata recovered from the clinical sample of a patient hospitalized for a trauma-related injury to his foot. The isolate was resistant to all beta-lactams, quinolones, trimetroprim-sulfametoxazol, gentamicin and tobramicyn. The bla NDM-1 gene was located in a conjugative plasmid that also contained the bla SHV-12 gene and was preceded by a disrupted insertion sequence of ISAba125. The plasmid belongs to the incompatibility group X3, which is known to be an important vector for NDM-1 dissemination in China. This is the first reported case of NDM-1L. adecarboxylata in our country and evidences that species of uncertain clinical relevance can act as hidden sources of clinically important resistance determinants. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Review of clinical studies of Polygonum multiflorum Thunb. and its isolated bioactive compounds.

    Science.gov (United States)

    Bounda, Guy-Armel; Feng, Y U

    2015-01-01

    Polygonum multiflorum Thunb. (PMT), officially listed in the Chinese Pharmacopoeia, is one of the most popular perennial Chinese traditional medicines known as He shou wu in China and East Asia, and as Fo-ti in North America. Mounting pharmacological studies have stressed out its key benefice for the treatment of various diseases and medical conditions such as liver injury, cancer, diabetes, alopecia, atherosclerosis, and neurodegenerative diseases as well. International databases such as PubMed/Medline, Science citation Index and Google Scholar were searched for clinical studies recently published on P. multiflorum. Various clinical studies published articles were retrieved, providing information relevant to pharmacokinetics-pharmacodynamics analysis, sleep disorders, dyslipidemia treatment, and neurodegenerative diseases. This review is an effort to update the clinical picture of investigations ever carried on PMT and/or its isolated bio-compounds and to enlighten its therapeutic assessment.

  19. Enzimotipagem de espécies do gênero Candida isoladas da cavidade bucal Enzymotiping of species of the genus Candida isolated from the oral cavity

    Directory of Open Access Journals (Sweden)

    Regina Celia Candido

    2000-10-01

    Full Text Available Foram avaliadas quanto a produção de exoenzimas fosfolipase e proteinase, 79 amostras de Candida isoladas da cavidade bucal de pacientes com lesões bucais características de candidose e indivíduos com boca clinicamente normal, atendidos na Faculdade de Odontologia de Ribeirão Preto USP. Dentre as cepas de C. albicans isoladas de lesões bucais, a fosfolipase e proteinase foram detectadas em, respectivamente, 83,3% e 66,7%. C. tropicalis e C. parapsilosis produziram somente proteinase. Quanto às cepas isoladas de nichos sem lesão, do total de 32 C. albicans, 71,9% apresentaram fosfolipase e 68,7% proteinase. C. tropicalis apresentou apenas a enzima proteinase, C. glabrata, C. krusei, C. guilliermondii e Candida spp, não apresentaram nenhuma das exoenzimas. Entre as amostras de C. albicans de ambos os grupos, o enzimotipo 22 (fosfolipase positiva e proteinase fracamente positiva foi prevalente. Enzimotipos diferentes foram detectados em amostras da mesma espécie provenientes de mesmo paciente.The production of phospholipase and proteinase exoenzymes was evaluated in seventy nine samples of Candida isolated from the oral cavity of patients with oral lesions characteristic of candidosis and from individuals presenting a clinically normal mouth, attended at the University of Dentistry of Ribeirão Preto USP. Among the strains of C. albicans isolated from oral lesions, the phospholipase and proteinase were detected in 83.3% and 66.7%, respectively. C. tropicalis and C. parapsilosis produced only proteinase. Regarding the isolated strains from niches without lesions, out of a total of 32 C. albicans, 71.9% presented phospholipase and 68.7% proteinase. C. tropicalis only presented the enzyme proteinase, C. glabrata, C. krusei, C. guilliermondii and Candida spp did not present any of the exoenzymes. Among the samples of C. albicans from both groups, the enzymotype 22 (positive phospholipase and proteinase weakly positive, was prevalent

  20. Antimicrobial susceptibility of Neisseria gonorrhoeae isolates from symptomatic men attending the Nanjing sexually transmitted diseases clinic (2011-2012): genetic characteristics of isolates with reduced sensitivity to ceftriaxone.

    Science.gov (United States)

    Li, Sai; Su, Xiao-Hong; Le, Wen-Jing; Jiang, Fa-Xing; Wang, Bao-Xi; Rice, Peter A

    2014-11-27

    Evolving gonococcal antimicrobial resistance (AMR) poses a serious threat to public health. The aim of this study was to: update antimicrobial susceptibility data of Neisseria gonorrhoeae recently isolated in Nanjing, China and identify specific deteminants of antimicrobial resistance and gentoypes of isolates with decreased sensitivity to ceftriaxone. 334 N. gonorrhoeae isolates were collected consecutively from symptomatic men attending the Nanjing STD Clinic between April 2011 and December 2012. The minimum inhibitory concentrations (MICs) for penicillin, tetracycline, ciprofloxacin, spectinomycin and ceftriaxone were determined by agar plate dilution for each isolate. Penicillinase-producing N. gonorrhoeae (PPNG) and tetracycline-resistant N. gonorrhoeae (TRNG) were examined and typed for β-lactamase and tetM encoding plasmids respectively. Isolates that displayed elevated MICs to ceftriaxone (MIC ≥0.125 mg/L) were also tested for mutations in penA, mtrR, porB1b, ponA and pilQ genes and characterized by Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST). 98.8% (330/334) of N. gonorrhoeae isolates were resistant to ciprofloxacin; 97.9% (327/334) to tetracycline and 67.7% (226/334) to penicillin. All isolates were susceptible to ceftriaxone (MIC ≤0.25 mg/L) and spectinomycin (MIC ≤32 mg/L). Plasmid mediated resistance was exhibited by 175/334 (52%) of isolates: 120/334 (36%) of isolates were PPNG and 104/334 (31%) were TRNG. 90.0% (108/120) of PPNG isolates carried the Asia type β-lactamase encoding plasmid and 96% (100/104) of TRNG isolates carried the Dutch type tetM containing plasmid. Elevated MICs for ceftriaxone were present in 15 (4.5%) isolates; multiple mutations were found in penA, mtrR, porB1b and ponA genes. The 15 isolates were distributed into diverse NG-MAST sequence types; four different non-mosaic penA alleles were identified, including one new type. N. gonorrhoeae isolates in Nanjing generally retained similar antimicrobial

  1. Antimicrobial susceptibility of clinically isolated anaerobic bacteria in a University Hospital Centre Split, Croatia in 2013.

    Science.gov (United States)

    Novak, Anita; Rubic, Zana; Dogas, Varja; Goic-Barisic, Ivana; Radic, Marina; Tonkic, Marija

    2015-02-01

    Anaerobic bacteria play a significant role in many endogenous polymicrobial infections. Since antimicrobial resistance among anaerobes has increased worldwide, it is useful to provide local susceptibility data to guide empirical therapy. The present study reports recent data on the susceptibility of clinically relevant anaerobes in a University Hospital Centre (UHC) Split, Croatia. A total of 63 Gram-negative and 59 Gram-positive anaerobic clinical isolates from various body sites were consecutively collected from January to December 2013. Antimicrobial susceptibility testing was performed using standardized methods and interpreted using EUCAST criteria. Patient's clinical and demographic data were recorded by clinical microbiologist. Among 35 isolates of Bacteroides spp., 97.1% were resistant to penicillin (PCN), 5.7% to amoxicillin/clavulanic acid (AMC), 8.6% to piperacillin/tazobactam (TZP), 29.0% to clindamycin (CLI) and 2.9% to metronidazole (MZ). Percentages of susceptible strains to imipenem (IPM), meropenem (MEM) and ertapenem (ETP) were 94.3. Resistance of other Gram-negative bacilli was 76.0% to PCN, 8.0% to AMC, 12.0% to TZP, 28.0% to CLI and 8% to MZ. All other Gram-negative strains were fully susceptible to MEM and ETP, while 96.0% were susceptible to IPM. Clostridium spp. isolates were 100% susceptible to all tested antibiotics except to CLI (two of four tested isolates were resistant). Propionibacterium spp. showed resistance to CLI in 4.3%, while 100% were resistant to MZ. Among other Gram-positive bacilli, 18.2% were resistant to PCN, 9.1% to CLI and 54.5% to MZ, while 81.8% of isolates were susceptible to carbapenems. Gram-positive cocci were 100% susceptible to all tested antimicrobials except to MZ, where 28.6% of resistant strains were recorded. Abdomen was the most common source of isolates (82.5%). The most prevalent types of infection were abscess (22.1%), sepsis (14.8%), appendicitis (13.9%) and peritonitis (6.6%). Twenty four patients (19

  2. [Mutations of DNA gyrase and topoisomerase IV in clinical isolates of fluoroquinolone-resistant Proteus mirabilis].

    Science.gov (United States)

    Saito, Ryoichi; Sato, Kenya; Kumita, Wakako; Inami, Natsuko; Nishiyama, Hiroyuki; Okamura, Noboru; Moriya, Kyoji; Koike, Kazuhiko

    2006-02-01

    The presence of fluoroquinolone resistance-associated mutations within the quinolone resistance-determining region of DNA gyrase and topoisomerase IV was investigated genetically in clinical isolates of Proteus mirabilis recovered from patients with urinay tract infections. Two isolates of fluoroquinolone-resistant P. mirabilis possessed the mutations in GyrA (Ser-83 --> Arg or Ile), GyrB (Ser-464 --> Tyr or Phe) and ParC (Ser-80 --> Ile). A novel mutation with Glu-87 --> Lys in GyrA, where suggested to be responsible for fluoroquinolone resistance, was identified. These results demonstrate that the presence of an additional mutation at Glu-87 in GyrA may contribute to high-level fluoroquinolone resistance, too.

  3. Distribution of genes encoding aminoglycoside-modifying enzymes among clinical isolates of methicillin-resistant staphylococci.

    Science.gov (United States)

    Perumal, N; Murugesan, S; Krishnan, P

    2016-01-01

    The objective of this study was to determine the distribution of genes encoding aminoglycoside-modifying enzymes (AMEs) and staphylococcal cassette chromosome mec (SCCmec) elements among clinical isolates of methicillin-resistant staphylococci (MRS). Antibiotic susceptibility test was done using Kirby-Bauer disk diffusion method. The presence of SCCmec types and AME genes, namely, aac (6')-Ie-aph (2''), aph (3')-IIIa and ant (4')-Ia was determined using two different multiplex polymerase chain reaction. The most encountered AME genes were aac (6')-Ie-aph (2'') (55.4%) followed by aph (3')-IIIa (32.3%) and ant (4')-Ia gene (9%). SCCmec type I (34%) was predominant in this study. In conclusion, the aac (6')-Ie-aph (2'') was the most common AME gene and SCCmec type I was most predominant among the MRS isolates.

  4. VTEC O157 subtypes associated with the most severe clinical symptoms in humans constitute a minor part of VTEC 0157 isolates from Danish Cattle

    DEFF Research Database (Denmark)

    Roldgaard, Bemt Bjørn; Scheutz, Flemming; Boel, Jeppe

    2004-01-01

    -positive VTEC 0 157 isolates (63 of bovine origin and 86 from human clinical cases) isolated between 1987 and 2001. All were analysed by vtx-PCR-RFLP and phage typing. The vtx-PCR-RFLP showed that isolates carrying the vtx2 gene was more than four times as prevalent among the human clinical isolates (55...

  5. [Genotyping of Cryptococcus neoformans/Cryptococcus gattii complex clinical isolates from Hospital "Dr. Julio C. Perrando", Resistencia city (Chaco, Argentina)].

    Science.gov (United States)

    Cattana, Maria E; Tracogna, Maria F; Fernández, Mariana S; Carol Rey, Mariana C; Sosa, Maria A; Giusiano, Gustavo E

    2013-01-01

    Cryptococcosis is a fungal infection caused by yeast species of Cryptococcus genus, particularly Cryptococcus neoformans/Cryptococcus gattii species complex. The knowledge of the cryptococcosis casuistic in northeastern Argentina is scarce and there is no information about the molecular types circulating in this area. The aim of this study was to genotyping C. neoformans/C. gattii complex clinical isolates obtained at Hospital "Dr. Julio C. Perrando", Resistencia city (Chaco, Argentina), in order to determine species, variety and molecular type. During two years and one month 26 clinical isolates were studied. Using conventional and molecular methods one isolate was identified as C. gattii VGI type, and 25 isolates as C. neoformans var. grubii; 23 of these belonged to VNI type and two belonged to VNII type. This data is a contribution to the knowledge of cryptococcosis epidemiology in Argentina and the first report about C. neoformans/ C. gattii complex molecular types from clinical isolates in northeastern Argentina.

  6. Impact of carbapenem heteroresistance among clinical isolates of invasive Escherichia coli in Chongqing, southwestern China.

    Science.gov (United States)

    Sun, J D; Huang, S F; Yang, S S; Pu, S L; Zhang, C M; Zhang, L P

    2015-05-01

    Although heteroresistance is common in a wide range of microorganisms, carbapenem heteroresistance among invasive Escherichia coli infections has not been reported. The objective of this study was to evaluate the clinical significance of carbapenem heteroresistance and to identify risk factors for its acquisition. A case-control study was conducted at a 3200-bed teaching hospital in Chongqing, southwestern China. Successive and non-duplicate nosocomial E. coli isolates (n = 332) were obtained from July 2011 to June 2013. Bloodstream isolates made up 50.6% of the strains collected. The rates of heteroresistance were 25.0% to imipenem, 17.2% to ertapenem, and 3.9% to meropenem. The population analysis profile revealed the presence of subpopulations with higher carbapenem resistance, showing MICs ranging from 2.0-128.0mg/L. Male gender, invasive intervention, antibiotic use and bacterial extended-spectrum β-lactamase (ESBL) production contributed to invasive infections by carbapenem-heteroresistant E. coli (CHEC). The production of ESBL was identified as the common independent risk factor for heteroresistance to both ertapenem and imipenem. Pulsed-field gel electrophoresis revealed clonal diversity among the CHEC isolates. Most importantly, characterization of two successive E. coli strains isolated from the same patient indicated that carbapenem resistance evolved from heteroresistance. In conclusion, the high prevalence of heteroresistance to carbapenem among invasive E. coli merits great attention. Routine detection of ESBLs and the prudent use of imipenem and ertapenem are advocated. The early targeted intervention should be formulated to reduce CHEC infection and carbapenem resistance of E. coli. Copyright © 2014 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  7. Novel Conserved Genotypes Correspond to Antibiotic Resistance Phenotypes of E. coli Clinical Isolates.

    Directory of Open Access Journals (Sweden)

    Michelle C Swick

    Full Text Available Current efforts to understand antibiotic resistance on the whole genome scale tend to focus on known genes even as high throughput sequencing strategies uncover novel mechanisms. To identify genomic variations associated with antibiotic resistance, we employed a modified genome-wide association study; we sequenced genomic DNA from pools of E. coli clinical isolates with similar antibiotic resistance phenotypes using SOLiD technology to uncover single nucleotide polymorphisms (SNPs unanimously conserved in each pool. The multidrug-resistant pools were genotypically similar to SMS-3-5, a previously sequenced multidrug-resistant isolate from a polluted environment. The similarity was evenly spread across the entire genome and not limited to plasmid or pathogenicity island loci. Among the pools of clinical isolates, genomic variation was concentrated adjacent to previously reported inversion and duplication differences between the SMS-3-5 isolate and the drug-susceptible laboratory strain, DH10B. SNPs that result in non-synonymous changes in gyrA (encoding the well-known S83L allele associated with fluoroquinolone resistance, mutM, ligB, and recG were unanimously conserved in every fluoroquinolone-resistant pool. Alleles of the latter three genes are tightly linked among most sequenced E. coli genomes, and had not been implicated in antibiotic resistance previously. The changes in these genes map to amino acid positions in alpha helices that are involved in DNA binding. Plasmid-encoded complementation of null strains with either allelic variant of mutM or ligB resulted in variable responses to ultraviolet light or hydrogen peroxide treatment as markers of induced DNA damage, indicating their importance in DNA metabolism and revealing a potential mechanism for fluoroquinolone resistance. Our approach uncovered evidence that additional DNA binding enzymes may contribute to fluoroquinolone resistance and further implicate environmental bacteria as a

  8. Novel Conserved Genotypes Correspond to Antibiotic Resistance Phenotypes of E. coli Clinical Isolates.

    Science.gov (United States)

    Swick, Michelle C; Evangelista, Michael A; Bodine, Truston J; Easton-Marks, Jeremy R; Barth, Patrick; Shah, Minita J; Bormann Chung, Christina A; Stanley, Sarah; McLaughlin, Stephen F; Lee, Clarence C; Sheth, Vrunda; Doan, Quynh; Hamill, Richard J; Steffen, David; Becnel, Lauren B; Sucgang, Richard; Zechiedrich, Lynn

    2013-01-01

    Current efforts to understand antibiotic resistance on the whole genome scale tend to focus on known genes even as high throughput sequencing strategies uncover novel mechanisms. To identify genomic variations associated with antibiotic resistance, we employed a modified genome-wide association study; we sequenced genomic DNA from pools of E. coli clinical isolates with similar antibiotic resistance phenotypes using SOLiD technology to uncover single nucleotide polymorphisms (SNPs) unanimously conserved in each pool. The multidrug-resistant pools were genotypically similar to SMS-3-5, a previously sequenced multidrug-resistant isolate from a polluted environment. The similarity was evenly spread across the entire genome and not limited to plasmid or pathogenicity island loci. Among the pools of clinical isolates, genomic variation was concentrated adjacent to previously reported inversion and duplication differences between the SMS-3-5 isolate and the drug-susceptible laboratory strain, DH10B. SNPs that result in non-synonymous changes in gyrA (encoding the well-known S83L allele associated with fluoroquinolone resistance), mutM, ligB, and recG were unanimously conserved in every fluoroquinolone-resistant pool. Alleles of the latter three genes are tightly linked among most sequenced E. coli genomes, and had not been implicated in antibiotic resistance previously. The changes in these genes map to amino acid positions in alpha helices that are involved in DNA binding. Plasmid-encoded complementation of null strains with either allelic variant of mutM or ligB resulted in variable responses to ultraviolet light or hydrogen peroxide treatment as markers of induced DNA damage, indicating their importance in DNA metabolism and revealing a potential mechanism for fluoroquinolone resistance. Our approach uncovered evidence that additional DNA binding enzymes may contribute to fluoroquinolone resistance and further implicate environmental bacteria as a reservoir for

  9. In vitro anti-tuberculosis activity of azole drugs against Mycobacterium tuberculosis clinical isolates.

    Science.gov (United States)

    Imperiale, Belén R; Cataldi, Ángel A; Morcillo, Nora S

    Latent tuberculosis has been associated with the persistence of dormant Mycobacterium tuberculosis in the organism of infected individuals, who are reservoirs of the bacilli and the source for spreading the disease in the community. New active anti-TB drugs exerting their metabolic action at different stages and on latent/dormant bacilli are urgently required to avoid endogenous reactivations and to be part of treatments of multi- and extensively-drug resistant tuberculosis (M/XDR-TB). It was previously reported that azole drugs are active against M. tuberculosis. For that reason, the aims of this study were to determine the in vitro activity of azole drugs, imidazole (clotrimazole, CLO and econazole, ECO) and nitroimidazole (metronidazole, MZ and ipronidazole, IPZ), against a collection of MDR M. tuberculosis clinical isolates; and to analyze their potential use in both the LTB and the active forms of M/XDR-TB treatments. A total of 55 MDR M. tuberculosis isolates and H37Rv were included. MZ and IPZ activity against M. tuberculosis isolates were tested using anaerobic culture conditions. The activity of ECO and CLO was measured by the minimal inhibitory concentration (MIC) using a microdilution colorimetric method. MZ and IPZ showed bacteriostatic activity against M. tuberculosis strains. MIC 50 and MIC 90 to ECO was 4.0μg/ml, while MIC 50 to CLO was 4.0μg/ml and MIC 90 was 8.0μg/ml respectively. All azole compounds tested in the study showed inhibitory activity against MDR M. tuberculosis clinical isolates. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Species distribution and antifungal susceptibility of Candida spp. isolated from superficial candidiasis in outpatients in Iran.

    Science.gov (United States)

    Razzaghi-Abyaneh, M; Sadeghi, G; Zeinali, E; Alirezaee, M; Shams-Ghahfarokhi, M; Amani, A; Mirahmadi, R; Tolouei, R

    2014-06-01

    Candidiasis is the most prevalent fungal infection affecting human and animals all over the world. This study represents the epidemiological aspects of superficial candidiasis in outpatients and in vitro antifungal susceptibility of etiologic Candida species. Clinical samples were taken from 173 patients including skin and nail scrapings (107; 61.8%), vaginal discharge (28; 16.2%), sputum (20; 11.6%), oral swabs (7; 4.0%), bronchoalveolar lavage (6; 3.5%) and 1 specimen (0.6%) of each eye tumor, gastric juice, urine, biopsy and urinary catheter and confirmed as candidiasis by direct microscopy, culture and histopathology. Susceptibility patterns of the isolated Candida species were determined using the disk diffusion and broth microdilution methods. Among 173 Candida isolates, C. albicans (72.3%) was the most prevalent species followed by C. parapsilosis (11.5%). Other identified species were C. glabrata, C. krusei, C. tropicalis, C. guilliermondii, C. intermedia and C. sake. Majority of the Candida isolates were susceptible to fluconazole (95.4%) followed by 5-flucytosine (89.6%), voriconazole (78.6%) itraconazole (48.0%) and ketoconazole (42.8%). Caspofungin was the most potent antifungal drug against C. albicans (MICs; 0.062-1 μg/mL), ketoconazole for C. parapsilosis and C. tropicalis (MICs; 0.031-0.25 μg/mL) and itraconazole for C. krusei, C. glabrata and C. guilliermondii (MICs; 0.031-1 μg/mL). This study reinforces the significance of superficial candidiasis as an important fungal infection with multiple clinical presentations. Our results further indicate that susceptibility testing to commonly used antifungals is crucial in order to select the appropriate therapeutic strategies which minimize complications while improving patients' life. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  11. Global transcriptional profiling of longitudinal clinical isolates of Mycobacterium tuberculosis exhibiting rapid accumulation of drug resistance.

    Science.gov (United States)

    Chatterjee, Anirvan; Saranath, Dhananjaya; Bhatter, Purva; Mistry, Nerges

    2013-01-01

    The identification of multidrug resistant (MDR), extensively and totally drug resistant Mycobacterium tuberculosis (Mtb), in vulnerable sites such as Mumbai, is a grave threat to the control of tuberculosis. The current study aimed at explaining the rapid expression of MDR in Directly Observed Treatment Short Course (DOTS) compliant patients, represents the first study comparing global transcriptional profiles of 3 pairs of clinical Mtb isolates, collected longitudinally at initiation and completion of DOTS. While the isolates were drug susceptible (DS) at onset and MDR at completion of DOTS, they exhibited identical DNA fingerprints at both points of collection. The whole genome transcriptional analysis was performed using total RNA from H37Rv and 3 locally predominant spoligotypes viz. MANU1, CAS and Beijing, hybridized on MTBv3 (BuG@S) microarray, and yielded 36, 98 and 45 differentially expressed genes respectively. Genes encoding transcription factors (sig, rpoB), cell wall biosynthesis (emb genes), protein synthesis (rpl) and additional central metabolic pathways (ppdK, pknH, pfkB) were found to be down regulated in the MDR isolates as compared to the DS isolate of the same genotype. Up regulation of drug efflux pumps, ABC transporters, trans-membrane proteins and stress response transcriptional factors (whiB) in the MDR isolates was observed. The data indicated that Mtb, without specific mutations in drug target genes may persist in the host due to additional mechanisms like drug efflux pumps and lowered rate of metabolism. Furthermore this population of Mtb, which also showed reduced DNA repair activity, would result in selection and stabilization of spontaneous mutations in drug target genes, causing selection of a MDR strain in the presence of drug pressures. Efflux pump such as drrA may play a significant role in increasing fitness of low level drug resistant cells and assist in survival of Mtb till acquisition of drug resistant mutations with least

  12. Global transcriptional profiling of longitudinal clinical isolates of Mycobacterium tuberculosis exhibiting rapid accumulation of drug resistance.

    Directory of Open Access Journals (Sweden)

    Anirvan Chatterjee

    Full Text Available The identification of multidrug resistant (MDR, extensively and totally drug resistant Mycobacterium tuberculosis (Mtb, in vulnerable sites such as Mumbai, is a grave threat to the control of tuberculosis. The current study aimed at explaining the rapid expression of MDR in Directly Observed Treatment Short Course (DOTS compliant patients, represents the first study comparing global transcriptional profiles of 3 pairs of clinical Mtb isolates, collected longitudinally at initiation and completion of DOTS. While the isolates were drug susceptible (DS at onset and MDR at completion of DOTS, they exhibited identical DNA fingerprints at both points of collection. The whole genome transcriptional analysis was performed using total RNA from H37Rv and 3 locally predominant spoligotypes viz. MANU1, CAS and Beijing, hybridized on MTBv3 (BuG@S microarray, and yielded 36, 98 and 45 differentially expressed genes respectively. Genes encoding transcription factors (sig, rpoB, cell wall biosynthesis (emb genes, protein synthesis (rpl and additional central metabolic pathways (ppdK, pknH, pfkB were found to be down regulated in the MDR isolates as compared to the DS isolate of the same genotype. Up regulation of drug efflux pumps, ABC transporters, trans-membrane proteins and stress response transcriptional factors (whiB in the MDR isolates was observed. The data indicated that Mtb, without specific mutations in drug target genes may persist in the host due to additional mechanisms like drug efflux pumps and lowered rate of metabolism. Furthermore this population of Mtb, which also showed reduced DNA repair activity, would result in selection and stabilization of spontaneous mutations in drug target genes, causing selection of a MDR strain in the presence of drug pressures. Efflux pump such as drrA may play a significant role in increasing fitness of low level drug resistant cells and assist in survival of Mtb till acquisition of drug resistant mutations with

  13. Molecular typing of Legionella pneumophila serogroup 1 clinical strains isolated in Italy.

    Science.gov (United States)

    Fontana, Stefano; Scaturro, Maria; Rota, Maria Cristina; Caporali, Maria Grazia; Ricci, Maria Luisa

    2014-07-01

    Molecular typing methods for discriminating different bacterial isolates are essential epidemiological tools in prevention and control of Legionella infections and outbreaks. A selection of 56 out of 184 Legionella pneumophila serogroup 1 (Lp1) clinical isolates, collected from different Italian regions between 1987 and 2012, and stored at the National Reference Laboratory for Legionella, were typed by monoclonal antibody (MAb) subgrouping, amplified fragment length polymorphism (AFLP) and sequence based typing (SBT). These strains were isolated from 39 community (69.6%), 14 nosocomial (25%) and 3 travel associated (5.4%) Legionnaires'disease cases. MAb typing results showed a prevalence of MAb 3/1 positive isolates (75%) with the Philadelphia subgroup representing 35.7%, followed by Knoxville (23.2%), Benidorm (12.5%), Allentown/France (1.8%), Allentown/France-Philadelphia (1.8%). The remaining 25% were MAb 3/1 negative, namely 11 Olda (19.6%), 2 Oxford (3.6%) and 1 Bellingham (1.8%) subgroups. AFLP analysis detected 20 different genomic profiles. SBT analysis revealed 32 different sequence types (STs) with high diversity of STs (IODSTs=0.952) 12 of which were never described before. ST1 and ST23 were most frequently isolated as observed worldwide. A helpful analysis of data from SBT, MAb subgrouping and AFLP is provided, as well as a comparison to the Lp1 types investigated from other countries. This study describes the first Italian Lp1 strains database, providing molecular epidemiology data useful for future epidemiological investigations, especially of travel associated Legionnaires' diseases (TALD) cases, Italy being the country associated with the highest number of clusters. Copyright © 2014 Elsevier GmbH. All rights reserved.

  14. Carbapenemase Production of Clinical Isolates Acinetobacter baumannii and Pseudomonas aeruginosa from a Bulgarian University Hospital.

    Science.gov (United States)

    Petrova, Atanaska P; Stanimirova, Irina D; Ivanov, Ivan N; Petrov, Michael M; Miteva-Katrandzhieva, Tsonka M; Grivnev, Vasil I; Kardjeva, Velichka S; Kantardzhiev, Todor V; Murdjeva, Mariana A

    2017-12-20

    Production of Bla OXA-23, OXA-24, OXA-58 and hyperexpression of OXA-51 due to ISAba1 insertion sequence are the leading causes of carbapenem resistance in Acinetobacter baumannii. The loss of OprD transmembrane protein and the overexpression of some effl ux pumps are considered to be the main factors for carbapenem resistance in Pseudomonas aeruginosa whereas metallo-enzymes' production has a secondary role. Тo examine the carbapenem resistance due to carbapenemase production among clinically signifi cant Gram-negative non-fermenters from St George University hospital, Plovdiv: A. baumannii and P. aeruginosa. Forty three A. baumannii and 43 P. aeruginosa isolates, resistant or with intermediate resistance to imipenem and/or meropenem were included in the study. They were collected from patients admitted in 14 various hospital wards between 2010 and 2014. Both phenotypic and genetic methods were used for identifi cation and antimicrobial susceptibility testing. All A. baumannii demonstrated carbapenemase production determined by a modifi ed Hodge test whereas P. aeruginosa isolates did not show this phenomenon. OXA-23 genes were determined in 97.7% (42 out of 43) of A. baumannii isolates indistinguishable from the sequence of the classical ARI-1 gene. OXA-24, OXA-58 and overexpression of OXA-51 were not registered in any of the isolates. All P. aeruginosa were negative for blaVIM and blaIMP genes. The leading cause of carbapenem resistance in A. baumannii isolates from our hospital is the carbapenemase production due to the expression of OXA- 23 gene, whereas in P. aeruginosa - the loss of transmembrane OprD protein and the effl ux pumps' hyperexpression are suspected to be the main mechanisms.

  15. Carbapenemase Production of Clinical Isolates Acinetobacter baumannii and Pseudomonas aeruginosa from a Bulgarian University Hospital

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    Petrova Atanaska P.

    2017-12-01

    Full Text Available Background: Production of Bla OXA-23, OXA-24, OXA-58 and hyperexpression of OXA-51 due to ISAba1 insertion sequence are the leading causes of carbapenem resistance in Acinetobacter baumannii. The loss of OprD transmembrane protein and the overexpression of some effl ux pumps are considered to be the main factors for carbapenem resistance in Pseudomonas aeruginosa whereas metallo-enzymes’ production has a secondary role. Aim: Тo examine the carbapenem resistance due to carbapenemase production among clinically signifi cant Gram-negative non-fermenters from St George University hospital, Plovdiv: A. baumannii and P. aeruginosa. Materials and methods: Forty three A. baumannii and 43 P. aeruginosa isolates, resistant or with intermediate resistance to imipenem and/or meropenem were included in the study. They were collected from patients admitted in 14 various hospital wards between 2010 and 2014. Both phenotypic and genetic methods were used for identifi cation and antimicrobial susceptibility testing. Results: All A. baumannii demonstrated carbapenemase production determined by a modifi ed Hodge test whereas P. aeruginosa isolates did not show this phenomenon. OXA-23 genes were determined in 97.7% (42 out of 43 of A. baumannii isolates indistinguishable from the sequence of the classical ARI-1 gene. OXA-24, OXA-58 and overexpression of OXA-51 were not registered in any of the isolates. All P. aeruginosa were negative for blaVIM and blaIMP genes. Conclusion: The leading cause of carbapenem resistance in A. baumannii isolates from our hospital is the carbapenemase production due to the expression of OXA- 23 gene, whereas in P. aeruginosa - the loss of transmembrane OprD protein and the effl ux pumps’ hyperexpression are suspected to be the main mechanisms.

  16. Multiple sclerosis presented as clinically isolated syndrome: the need for early diagnosis and treatment

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    Sigliti-Henrietta Pelidou

    2008-06-01

    Full Text Available Sigliti-Henrietta Pelidou, Sotirios Giannopoulos, Sotiria Tzavidi, Georgios Lagos, Athanassios P KyritsisDepartment of Neurology, University of Ioannina School of Medicine, GreeceObjective: To aid in the timely diagnosis of patients who present with clinically isolated syndrome (CIS.Patients and methods: We studied 25 patients (18 women, 7 men, originally presented in our clinic with a CIS suggestive of multiple sclerosis (MS. All patients underwent the full investigation procedure including routine tests, serology, cerebrospinal fluid (CSF examinations, evoked potentials (EPs, and magnetic resonance imaging (MRI of brain and cervical spinal cord. Patients were imaged at baseline, and every three months thereafter up to a year.Results: The CIS was consisted of optic neuritis in 12 cases, incomplete transverse myelitis (ITM in 7 cases, Lhermitte sign in 2 cases, internuclear ophthalmoplegia (INO in 2 cases, mild brainstem syndrome in 1 case, and tonic-clonic seizures in 1 case. Using the baseline and three-month scans 18/25 (72% patients developed definite MS in one year of follow up while 7 (28% had no further findings during this observation period. Immunomodulatory treatments were applied to all definite MS patients.Conclusion: In light of new treatments available, MRIs at 3 month intervals are helpful to obtain the definite diagnosis of MS as early as possible.Keywords: multiple sclerosis, clinically isolated syndrome, optic neuritis, transverse myelitis

  17. Clinical isolates of Acinetobacter baumannii from a Portuguese hospital: PFGE characterization, antibiotic susceptibility and biofilm-forming ability.

    Science.gov (United States)

    Duarte, Andreia; Ferreira, Susana; Almeida, Sofia; Domingues, Fernanda C

    2016-04-01

    Acinetobacter baumannii is an emerging pathogen associated with nosocomial infections that in addition has shown an increasing resistance to antibiotics. In this work the genetic diversity of A. baumannii isolates from a Portuguese hospital, their antibiotic resistance profiles and ability to form biofilms was studied. Seventy-nine clinical A. baumannii isolates were characterized by pulsed-field gel electrophoresis (PFGE) with 9 different PFGE profiles being obtained. Concerning the antimicrobial susceptibility, all A. baumannii isolates were resistant to 12 of the 17 tested antibiotics and classified as multidrug-resistant (MDR). In addition, 74.7% of the isolates showed biofilm formation ability, however no statistical significance with antibiotic resistance was observed. In contrast, urine samples isolates were more likely to form biofilms than strains isolated from other sources. Our findings highlight the high number of MDR A. baumannii isolates and the importance of the formation of biofilms as a potential virulence factor. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. CLINICAL ISOLATES OF MECA, METHICILLIN, VANCOMYCIN RESISTANCE S. AUREUS; ESBLs PRODUCING K.PNEUMONIA, E.COLI, P. AUREGENOSA FROM VARIOUS CLINICAL SOURCE AND ITS ANTIMICROBIAL RESISTANCE PATTERNS

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    Ismail Mahmud Ali, Amirthalingam R

    2015-01-01

    Full Text Available Background and Objective: Antimicrobial resistance has turned into a key medical and public health crisis globally since the injudicious use of magic bullets (drugs. Aim of this study is focused on the clinical isolate and their percentages of resistant to antibiotics in gram positive bacteria such as MRSA, VRSA, and MSSA are common causes of nosocomical, skin structure infections, bacteremia and infection of other systems; ESBLs producing Enterobacteriaceae (E. coli, Klebsiella spp. is common agent of urinary tract, bloodstream, pulmonary and intra-abdominal infections and carbapenem resistant P. aeruginosa with its complete antimicrobial patterns which are currently practiced in this population. Methods: There are one hundred and fourteen (114 various clinical isolates, isolated from various clinical samples like throat swab, urine, pus, sputum, and blood culture, identified as specific isolate with resistance patterns were analyzed by BD phoenix-100 the auto analyzer. Results: Off 114 clinical isolate, 6 mecA-mediated resistance (cefoxitin>8mgc/ml, 11 methicillin resistance, 18 β lactam/βlactamase inhibitor, 12 methicillin sensitive and 3 vancomycin (>16µg/ml resistance S. aureus have been isolated from overall 50 isolate of S.aureus. In addition, there are 27 P.aeruginosa, 15 ESBLs from overall of 25 K. pneumoniae and 7 ESBLs out of 12 Escherichia coli species have been isolated. The resistance and susceptibility pattern percentages have been graphically represented for each isolates. Conclusion: Current study revealed that the drug classes of β lactam/βlactamase inhibitor having high resistance rate with S.aureus, P.aureginosa, K. pneumoniae and E. coli isolate. Also, some of other drug classes such as cepham and tetracycline having higher resistance rate with P.aureginosa and K.pneumoniae. In addition, the vancomycin resistances S. aureus have been isolated and reported as first time in this population.

  19. Prevalence of the Panton-Valentine Leukocidin Gene in Clinical Isolates of Staphylococcus aureus Isolated From Hospitals the Ilam Province of Iran

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    Rostamzad

    2016-01-01

    Full Text Available Background Panton-Valentine leukocidin (luk-pv is a cytotoxin that causes leukocyte destruction and tissue necrosis. Objectives The aim of this study was to determine the prevalence of the pv1, femA, and mecA genes in staphylococcus aureus isolates from clinical specimens in hospitals in Ilam, Iran. Materials and Methods One hundred and sixty Staphylococcus aureus isolates were collected from hospitals in Ilam, Iran, and phenotypic and genotypic examinations for methicillin-resistant S. aureus (MRSA isolates were carried out. The antibiotic profiles of these isolates, and the minimal inhibitory concentration (MIC of MRSA isolates was determined using the agar dilution method with vancomycin, cefoxitin, and oxacillin. All isolates were examined using polymerase chain reaction (PCR primers for the femA, mecA, and Panton Valentine leukocidin (luk-pv genes. Results The results showed 91 isolates (56.88% were coagulase-positive, and 69 isolates (43.12% were coagulase-negative Staphylococcus aureus (CNSA. Out of 91 (56.88% coagulase-positive staphylococci, 32 isolates (35.16% were resistant to cefoxitin, and 30 isolates (32.96% were resistant to oxacillin, using disc diffusion method. PCR revealed the presence of the femA gene (510 bp band in all coagulase-positive isolates (100%, and the mecA gene (513 bp band was detected in 32 isolates (35.16%; out of 32 MRSA isolates, 13 isolates (40.62% were positive for presence of the luk-pv gene (433 bp band. Conclusions The cefoxitin disk diffusion method showed the best results when compared to oxacillin disk, similar to results from detecting the mecA gene in PCR as a golden test. Studies on MRSA that carry the luk-pv gene should continue to provide significant insight into the prevalence and epidemiology of these important resistant pathogens. Also, the rate of pvl gene-producing isolates showed to be relatively high, and it should be detected in all staphylococcal infections.

  20. Drug susceptibility testing of clinical isolates of streptococci and enterococci by the Phoenix automated microbiology system

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    Sokeng Gertrude

    2007-05-01

    Full Text Available Abstract Background Drug resistance is an emerging problem among streptococcal and enterococcal species. Automated diagnostic systems for species identification and antimicrobial susceptibility testing (AST have become recently available. We evaluated drug susceptibility of clinical isolates of streptococci and enterococci using the recent Phoenix system (BD, Sparks, MD. Diagnostic tools included the new SMIC/ID-2 panel for streptococci, and the PMIC/ID-14 for enterococci. Two-hundred and fifty isolates have been investigated: β-hemolytic streptococci (n = 65, Streptococcus pneumoniae (n = 50, viridans group streptococci (n = 32, Enterococcus faecium (n = 40, Enterococcus faecalis (n = 43, other catalase-negative cocci (n = 20. When needed, species ID was determined using molecular methods. Test bacterial strains were chosen among those carrying clinically-relevant resistance determinants (penicillin, macrolides, fluoroquinolones, glycopeptides. AST results of the Phoenix system were compared to minimal inhibitory concentration (MIC values measured by the Etest method (AB Biodisk, Solna, Sweden. Results Streptococci: essential agreement (EA and categorical agreement (CA were 91.9% and 98.8%, respectively. Major (ME and minor errors (mE accounted for 0.1% and 1.1% of isolates, respectively. No very major errors (VME were produced. Enterococci: EA was 97%, CA 96%. Small numbers of VME (0.9%, ME (1.4% and mE (2.8% were obtained. Overall, EA and CA rates for most drugs were above 90% for both genera. A few VME were found: a teicoplanin and high-level streptomycin for E. faecalis, b high-level gentamicin for E. faecium. The mean time to results (± SD was 11.8 ± 0.9 h, with minor differences between streptococci and enterococci. Conclusion The Phoenix system emerged as an effective tool for quantitative AST. Panels based on dilution tests provided rapid and accurate MIC values with regard to clinically-relevant streptococcal and enterococcal

  1. Antimicrobial activity of some sulfonamide derivatives on clinical isolates of Staphylococus aureus

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    Bekdemir Yunus

    2008-08-01

    Full Text Available Abstract Background Staphylococcus aureus is a non-motile, gram positive, non-sporforming, facultative anaerobic microorganism. It is one of the important bacteria as a potential pathogen specifically for nosocomial infections. The sulfonamide derivative medicines are preferred to cure infection caused by S. aureus due to methicillin resistance. Methods Antimicrobial activity of four sulfonamide derivatives have been investigated against 50 clinical isolates of S. aureus and tested by using MIC and disc diffusion methods. 50 clinical isolate which collected from specimens of patients who are given medical treatment in Ondokuz Mayis University Medical School Hospital. A control strain of S. aureus ATCC 29213 was also tested. Results The strongest inhibition was observed in the cases of I [N-(2-hydroxy-4-nitro-phenyl-4-methyl-benzensulfonamid], and II [N-(2-hydroxy-5-nitro-phenyl-4-methyl-benzensulfonamid] against S. aureus. Compound I [N-(2-hydroxy-4-nitro-phenyl-4-methyl-benzensulfonamid] showed higher effect on 21 S. aureus MRSAisolates than oxacillin antibiotic. Introducing an electron withdrawing on the ring increased the antimicrobial activity remarkably. Conclusion This study may help to suggest an alternative possible leading compound for development of new antimicrobial agents against MRSA and MSSA resistant S. aureus. It was also shown here that that clinical isolates of 50 S. aureus have various resistance patterns against to four sulfonamide derivatives. It may also be emphasized here that in vitro antimicrobial susceptibility testing results for S. aureus need standardization with further studies and it should also have a correlation with in vivo therapeutic response experiments.

  2. Characterization of ceftazidime resistance mechanisms in clinical isolates of Burkholderia pseudomallei from Australia.

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    Derek S Sarovich

    Full Text Available Burkholderia pseudomallei is a gram-negative bacterium that causes the serious human disease, melioidosis. There is no vaccine against melioidosis and it can be fatal if not treated with a specific antibiotic regimen, which typically includes the third-generation cephalosporin, ceftazidime (CAZ. There have been several resistance mechanisms described for B. pseudomallei, of which the best described are amino acid changes that alter substrate specificity in the highly conserved class A β-lactamase, PenA. In the current study, we sequenced penA from isolates sequentially derived from two melioidosis patients with wild-type (1.5 µg/mL and, subsequently, resistant (16 or ≥256 µg/mL CAZ phenotypes. We identified two single-nucleotide polymorphisms (SNPs that directly increased CAZ hydrolysis. One SNP caused an amino acid substitution (C69Y near the active site of PenA, whereas a second novel SNP was found within the penA promoter region. In both instances, the CAZ resistance phenotype corresponded directly with the SNP genotype. Interestingly, these SNPs appeared after infection and under selection from CAZ chemotherapy. Through heterologous cloning and expression, and subsequent allelic exchange in the native bacterium, we confirmed the role of penA in generating both low-level and high-level CAZ resistance in these clinical isolates. Similar to previous studies, the amino acid substitution altered substrate specificity to other β-lactams, suggesting a potential fitness cost associated with this mutation, a finding that could be exploited to improve therapeutic outcomes in patients harboring CAZ resistant B. pseudomallei. Our study is the first to functionally characterize CAZ resistance in clinical isolates of B. pseudomallei and to provide proven and clinically relevant signatures for monitoring the development of antibiotic resistance in this important pathogen.

  3. White-opaque Switching in Different Mating Type-like Locus Gene Types of Clinical Candida albicans Isolates

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    Hou-Min Li

    2016-01-01

    Conclusions: From these analyses, there were comparatively more C. albicans strains classified into serotype B, and the frequency of opaque phase strains was significant in the clinical isolates from China. Genetic, phenotypic, or drug susceptibility patterns were not significantly different from previous studies. MTL a/α isolates could also undergo WO switching which facilitates their survival.

  4. In vitro antifungal susceptibility and molecular identity of 99 clinical isolates of the opportunistic fungal genus Curvularia

    NARCIS (Netherlands)

    Cunha, da K.C.; Sutton, D.A.; Fothergill, A.W.; Gené, J.; Cano, J.; Madrid, H.; Hoog, de G.S.; Crous, P.W.; Guarro, J.

    2013-01-01

    The in vitro antifungal susceptibility of a set of 99 clinical isolates of Curvularia was tested against 9 drugs using a reference microdilution method. The isolates had been identified previously to species level by comparing their ITS rDNA and glyceraldehyde-3-phosphate dehydrogenase gene

  5. Molecular characterization and antibiotic resistance of clinical isolates of methicillin-resistant Staphylococcus aureus obtained from Southeast of Iran (Kerman).

    Science.gov (United States)

    Sadeghi, Javid; Mansouri, Shahla

    2014-05-01

    Staphylococcus aureus infections, particularly infections caused by methicillin-resistant S. aureus (MRSA) strains, are emerging as a major public health problem. The aim of this study was to determine the prevalence of MRSA, antibiotic resistance profile and staphylococcal cassette chromosome mec (SCCmec) type of MRSA isolates obtained from clinical samples. Totally, 162 S. aureus isolates were obtained from clinical samples at three university hospitals in Kerman, Iran from March 2011 to February 2012. All isolates were identified as S. aureus by phenotypic methods and confirmed by PCR amplification of the nuc gene. MRSA isolates were screened by phenotypic tests and confirmed by presence of mecA gene. The minimum inhibitory concentrations (MICs) of the MRSA isolates against antibacterial agents were determined by E-test. All isolates were analyzed by PCR for the presence of mecA and pvl genes. SCCmec typing of MRSA isolates was performed by multiplex PCR assay. Strain typing was carried out with REP-PCR. Using mecA gene PCR and phenotypic methods, 56.8% of the isolates were identified as MRSA. All MRSA isolates were susceptible to vancomycin and linezolid. The sensitivity of MRSA isolates to trimethoprim-sulfamethoxazole, clindamycin, ciprofloxacin, gentamicin, and erythromycin was 70.66, 66.53, 42.4, 38.05, and 29.35%, respectively. The most frequent SCCmec types were type III (48.31%) followed by type V (19.1%), type I (16.85%), and type IV (3.37%). The pvl gene was detected in 3.08% of isolates (two MRSA and three MSSA isolates). REP-PCR typing divided the 92 MRSA isolates into 10 distinct clusters. Our results indicate that vancomycin and linezolid are the most effective antibacterial agents against MRSA isolates and SCCmec type III is predominant in MRSA strains in this area. © 2013 APMIS. Published by John Wiley & Sons Ltd.

  6. A cfr-positive clinical staphylococcal isolate from India with multiple mechanisms of linezolid-resistance

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    Vineeth Rajan

    2014-01-01

    Full Text Available Background & objectives: Linezolid, a member of the oxazolidinone class of antibiotics, has been an effective therapeutic option to treat severe infections caused by multidrug resistant Gram positive bacteria. Emergence of linezolid resistant clinical strains is a serious issue in the healthcare settings worldwide. We report here the molecular characterization of a linezolid resistant clinical isolate of Staphylococcus haemolyticus from India. Methods: The species of the clinical isolate was identified by 16S rRNA gene sequencing. The minimum inhibitory concentrations (MICs of linezolid, clindamycin, chloramphenicol and oxacillin were determined by E-test method. To elucidate the mechanism of linezolid-resistance, presence of cfr gene (chloramphenicol florfenicol resistance and mutations in 23S rRNA and ribosomal proteins (L3, L4 and L22 were investigated. Staphylococcal Cassette Chromosome mec (SCCmec typing was performed by multiplex PCR. Results: The study documented a rare clinical S. haemolyticus strain with three independent mechanisms of linezolid-resistance. The strain carried cfr gene, the only known transmissible mechanism of linezolid-resistance. The strain also possessed resistance-conferring mutations such as G 2576 T in domain V of 23S rRNA gene and Met 156 Thr in L3 ribosomal protein. The other ribosomal proteins (L4 and L22 did not exhibit mutations accountable for linezolid-resistance. Restriction digestion by NheI revealed that all the alleles of 23S rRNA gene were mutated. The isolate showed elevated MIC values (>256 ΅g ml -[1] of linezolid, clindamycin, chloramphenicol and oxacillin. Methicillin resistance was conferred by type I SCCmec element. The strain also harboured lsa(B gene which encodes an ABC transporter that can efflux clindamycin. Interpretation & conclusions: The present study reports the first clinical strain from India with transmissible and multiple mechanisms of linezolid-resistance. Judicious use of

  7. Clinical heterogeneity and novel mutations in the glycerol kinase gene in three families with isolated glycerol kinase deficiency

    NARCIS (Netherlands)

    Sjarif, D. R.; Sinke, R. J.; Duran, M.; Beemer, F. A.; Kleijer, W. J.; Ploos van Amstel, J. K.; Poll-The, B. T.

    1998-01-01

    Isolated glycerol kinase deficiency (GKD) is an X linked recessive disorder. The clinical and biochemical picture may vary from a childhood metabolic crisis to asymptomatic adult "pseudohypertriglyceridaemia", the result of hyperglycerolaemia. We performed glycerol kinase (GK) gene analysis to study

  8. Antimicrobial Activity of Solithromycin against Clinical Isolates of Legionella pneumophila Serogroup 1

    OpenAIRE

    Mallegol, Julia; Fernandes, Prabhavathi; Melano, Roberto G.; Guyard, Cyril

    2014-01-01

    The activity of solithromycin was evaluated against clinical Legionella pneumophila serogroup 1 (Lp1) isolates (n = 196) collected in Ontario, Canada, from 1980 to 2011. Its in vitro activity was compared to that of azithromycin (AZM) using the broth microdilution method. Solithromycin had a MIC50 of ≤0.015 μg/ml and a MIC90 of 0.031 μg/ml, making its activity at least 8-fold to 32-fold higher than that of AZM (MIC50 and MIC90, 0.125 μg/ml and 1 μg/ml, respectively). Ninety-nine percent of th...

  9. 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 327...... multiresistant to other antimicrobials. Studies are needed to determine the sources of different multidrug-resistant serotypes. Continued national surveillance is underway to monitor changes in resistance trends and to detect further emergence of resistant Salmonella serotypes in Taiwan. (c) 2006 Elsevier Inc...

  10. Unique sequence features of the Human Adenovirus 31 complete genomic sequence are conserved in clinical isolates

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    Darr Sebastian

    2009-11-01

    Full Text Available Abstract Background Human adenoviruses (HAdV are causing a broad spectrum of diseases. One of the most severe forms of adenovirus infection is a disseminated disease resulting in significant morbidity and mortality. Several reports in recent years have identified HAdV-31 from species A (HAdV-A31 as a cause of disseminated disease in children following haematopoetic stem cell transplantation (hSCT and liver transplantation. We sequenced and analyzed the complete genome of the HAdV-A31 prototype strain to uncover unique sequence motifs associated with its high virulence. Moreover, we sequenced coding regions known to be essential for tropism and virulence (early transcription units E1A, E3, E4, the fiber knob and the penton base of HAdV-A31 clinical isolates from patients with disseminated disease. Results The genome size of HAdV-A31 is 33763 base pairs (bp in length with a GC content of 46.36%. Nucleotide alignment to the closely related HAdV-A12 revealed an overall homology of 84.2%. The genome organization into early, intermediate and late regions is similar to HAdV-A12. Sequence analysis of the prototype strain showed unique sequence features such as an immunoglobulin-like domain in the species A specific gene product E3 CR1 beta and a potentially integrin binding RGD motif in the C-terminal region of the protein IX. These features were conserved in all analyzed clinical isolates. Overall, amino acid sequences of clinical isolates were highly conserved compared to the prototype (99.2 to 100%, but a synonymous/non synonymous ratio (S/N of 2.36 in E3 CR1 beta suggested positive selection. Conclusion Unique sequence features of HAdV-A31 may enhance its ability to escape the host's immune surveillance and may facilitate a promiscuous tropism for various tissues. Moderate evolution of clinical isolates did not indicate the emergence of new HAdV-A31 subtypes in the recent years.

  11. Unique sequence features of the Human adenovirus 31 complete genomic sequence are conserved in clinical isolates.

    Science.gov (United States)

    Hofmayer, Soeren; Madisch, Ijad; Darr, Sebastian; Rehren, Fabienne; Heim, Albert

    2009-11-25

    Human adenoviruses (HAdV) are causing a broad spectrum of diseases. One of the most severe forms of adenovirus infection is a disseminated disease resulting in significant morbidity and mortality. Several reports in recent years have identified HAdV-31 from species A (HAdV-A31) as a cause of disseminated disease in children following haematopoetic stem cell transplantation (hSCT) and liver transplantation. We sequenced and analyzed the complete genome of the HAdV-A31 prototype strain to uncover unique sequence motifs associated with its high virulence. Moreover, we sequenced coding regions known to be essential for tropism and virulence (early transcription units E1A, E3, E4, the fiber knob and the penton base) of HAdV-A31 clinical isolates from patients with disseminated disease. The genome size of HAdV-A31 is 33763 base pairs (bp) in length with a GC content of 46.36%. Nucleotide alignment to the closely related HAdV-A12 revealed an overall homology of 84.2%. The genome organization into early, intermediate and late regions is similar to HAdV-A12. Sequence analysis of the prototype strain showed unique sequence features such as an immunoglobulin-like domain in the species A specific gene product E3 CR1 beta and a potentially integrin binding RGD motif in the C-terminal region of the protein IX. These features were conserved in all analyzed clinical isolates. Overall, amino acid sequences of clinical isolates were highly conserved compared to the prototype (99.2 to 100%), but a synonymous/non synonymous ratio (S/N) of 2.36 in E3 CR1 beta suggested positive selection. Unique sequence features of HAdV-A31 may enhance its ability to escape the host's immune surveillance and may facilitate a promiscuous tropism for various tissues. Moderate evolution of clinical isolates did not indicate the emergence of new HAdV-A31 subtypes in the recent years.

  12. In Vitro Synergistic Activity of Antimicrobial Agents in Combination against Clinical Isolates of Colistin-Resistant Acinetobacter baumannii

    OpenAIRE

    Bae, Seongman; Kim, Min-Chul; Park, Su-Jin; Kim, Hee Sueng; Sung, Heungsup; Kim, Mi-Na; Kim, Sung-Han; Lee, Sang-Oh; Choi, Sang-Ho; Woo, Jun Hee; Kim, Yang Soo; Chong, Yong Pil

    2016-01-01

    Emerging resistance to colistin in clinical Acinetobacter baumannii isolates is of growing concern. Since current treatment options for these strains are extremely limited, we investigated the in vitro activities of various antimicrobial combinations against colistin-resistant A. baumannii. Nine clinical isolates (8 from bacteremia cases and 1 from a pneumonia case) of colistin-resistant A. baumannii were collected in Asan Medical Center, Seoul, South Korea, between January 2010 and December ...

  13. High Prevalence of AmpC β-Lactamases in Clinical Isolates of Escherichia coli in Ilam, Iran

    OpenAIRE

    Maleki, Abbas; Khosravi, Afra; Ghafourian, Sobhan; Pakzad, Iraj; Hosseini, Shiva; Ramazanzadeh, Rashid; Sadeghifard, Nourkhoda

    2015-01-01

    Objectives Widespread use of β-lactam antibiotics could cause resistance to this group of antibiotics in pathogenic bacteria through the production of the enzyme β-lactamases. The aim of this study is to determine the molecular detection of AmpC β-lactamases among clinical Escherichia coli isolated from Ilam hospitals in Ilam, Iran. Methods One hundred and twelve clinical isolates of E. coli were collected from hospitalized patients and were identified by biochemical tests. They were evaluate...

  14. Does vitamin D deficiency predict early conversion of clinically isolated syndrome? A preliminary Egyptian study.

    Science.gov (United States)

    Shaheen, Hala A; Sayed, Sayed S; Daker, Lamiaa I; AbdelAziz, Hossam Eldin; Taha, Mohamed A

    2018-03-15

    It has been suggested that vitamin D influences the immunoregulation and subsequently affects the risk for conversion of clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (MS). There is little information regarding the relationship between levels of vitamin D and CIS conversion to MS in Egyptian patients. It is to study contribution of vitamin D deficiency to conversion of CIS to clinically definite multiple sclerosis (CDMS) and correlation of vitamin D level to cognitive and magnetic resonance imaging (MRI) results. A longitudinal prospective case control study was conducted on 43 Egyptian patients diagnosed as CIS according to McDonald criteria (2010). Clinical presentation, brain MRI and 25-hydroxyvitamin D levels were evaluated at baseline and after one-year follow-up. The CIS patients that converted to MS showed significant lower vitamin D level (p < 0.001) than the non-convertors. Multivariate logistic regression analysis revealed that the CIS patients with lower 25-hydroxyvitamin D level (p < 0.001) are at higher risk for early conversion to MS. There was a significant positive correlation between the vitamin D level and PASAT (r = 0.36, p = 0.02). It was found that there was a significant negative correlation between vitamin D level and MRI T 2 load (r = -0.38, p = 0.01). The low level of 25-hydroxyvitamin D may predict early conversion to clinically definite MS. Early vitamin D supplementation is recommended in patients with CIS.

  15. Clinical outcomes of isolated renal failure compared to other forms of organ failure in patients with severe acute pancreatitis.

    Science.gov (United States)

    Gougol, Amir; Dugum, Mohannad; Dudekula, Anwar; Greer, Phil; Slivka, Adam; Whitcomb, David C; Yadav, Dhiraj; Papachristou, Georgios I

    2017-08-07

    To assess differences in clinical outcomes of isolated renal failure (RF) compared to other forms of organ failure (OF) in patients with severe acute pancreatitis (SAP). Using a prospectively maintained database of patients with acute pancreatitis admitted to a tertiary medical center between 2003 and 2016, those with evidence of persistent OF were classified to renal, respiratory, cardiovascular, or multi-organ (2 or more organs). Data regarding demographics, comorbidities, etiology of acute pancreatitis, and clinical outcomes were prospectively recorded. Differences in clinical outcomes after development of isolated RF in comparison to other forms of OF were determined using independent t and Mann-Whitney U tests for continues variables, and χ 2 test for discrete variables. Among 500 patients with acute pancreatitis, 111 patients developed persistent OF: mean age was 54 years, and 75 (67.6%) were male. Forty-three patients had isolated OF: 17 (15.3%) renal, 25 (21.6%) respiratory, and 1 (0.9%) patient with cardiovascular failure. No differences in demographics, etiology of acute pancreatitis, systemic inflammatory response syndrome scores, or development of pancreatic necrosis were seen between patients with isolated RF vs isolated respiratory failure. Patients with isolated RF were less likely to require nutritional support (76.5% vs 96%, P = 0.001), ICU admission (58.8% vs 100%, P = 0.001), and had shorter mean ICU stay (2.4 d vs 15.7 d, P failure. None of the patients with isolated RF or isolated respiratory failure died. Among patients with SAP per the Revised Atlanta Classification, approximately 15% develop isolated RF. This subgroup seems to have a less protracted clinical course compared to other forms of OF. Isolated RF might be weighed less than isolated respiratory failure in risk predictive modeling of acute pancreatitis.

  16. A Novel Amphibian Tier 2 Testing Protocol: A 30-Week Exposure of Xenopus Tropicalis to the Antiandrogen Flutamide

    National Research Council Canada - National Science Library

    Knechtges, Paul L; Sprando, Robert L; Porter, Karen L; Brennan, Linda M; Miller, Mark F; Kumsher, David M; Dennis, William E; Brown, Charles C; Clegg Paul L. Knechtges. Robert L. Sprando. Karen L. Potter., Eric D

    2007-01-01

    .... For that reason, a tier 2 testing protocol using Xenopus (Silurana) tropicalis and a 30-week, flow-through exposure to the antiandrogen flutamide from stage 46 tadpoles through sexually mature adult frogs were developed and evaluated in this pilot study...

  17. Prevalence of integrons and Antimicrobial Resistance Genes Among Clinical Isolates of Enterobacter spp. From Hospitals of Tehran

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    Kobra Salimian Rizi

    2015-02-01

    Full Text Available Background: Enterobacter infections are increasingly recognized as an important nosocomial infection. Here we describe the prevalence of three classes of integrons in clinical isolates of Enterobacter spp. and the prevalence of antibiotic resistance genes among isolates with integron. Objectives: Here we describe the prevalence of integrons genes among clinical isolates of Enterobacter spp. and antibiotic susceptibility pattern, ESBL production and the prevalence of resistance genes among clinical isolates of Enterobacter spp. Materials and Methods: A total of 110 Enterobacter isolates collected from four hospitals in Tehran during 2012-2013. Enterobacter species were identified by using API 20E system. The existence of integron classes was investigated by PCR assay through the amplification of integrase genes. Then, antibacterial susceptibility and confirmation of ESBL phenotype was determined. Then, the bla groups, blaTEM, blaSHV, blaCTX-M-1 and aminoglycoside modifying enzymes genes were identified by PCR with specific primers. Results: The prevalence of Enterobacter species were E. cloacae (78.2 %, E. aerogenes (13.6 % and E. sakazakii (8.2%. They were from different clinical sources. Forty five of Enterobacter isolates have integron but there was not detected class 3 of integrons. All isolates with integron were susceptible to imipenem. Ten isolates of Enterobacter with integron showed ESBL phenotype. The frequency of blaTEM, blaSHV and blaCTX-M-1 genes are 20%, 0% and 15.6%, respectively. The frequency of genes encoding ANT (2˝-Ia, APH (3΄-Ia, AAC (6΄-Ib and AAC (3-IIa were 11.1%, 13.3%, 13.3 % and 20 %, respectively. Conclusions: The high prevalence of integron-positive isolates in our MDR Enterobacter isolates indicates that these mobile genetic elements are common among different Enterobacter spp. and associate with reduced susceptibility to the first-line antimicrobial drugs. This so highlight the continued monitoring of drug

  18. Physiological, morphological, and immunochemical parameters used for the characterization of clinical and environmental isolates of Acanthamoeba.

    Science.gov (United States)

    Becker-Finco, A; Costa, A O; Silva, S K; Ramada, J S; Furst, C; Stinghen, A E; De Figueiredo, B C; De Moura, J; Alvarenga, L M

    2013-03-01

    The factors that characterize Acanthamoeba strains as harmless or potentially pathogenic have not been elucidated. Analysing the in vitro and in vivo parameters of Acanthamoeba samples, including heat tolerance at temperatures close to that of the human body, cytopathic effects, and their ability to cause infections in animals, has been proposed to identify their pathogenic potential. Another promising criterion for differentiating strains is the analysis of their biochemical and immunochemical properties. In this study, a comparative evaluation between clinical and environmental Acanthamoeba isolates was performed on the basis of physiological, morphological, and immunochemical criteria. Crude antigens were used to characterize the protein profiles by electrophoresis and immunize mice to produce polyclonal and monoclonal antibodies. The antibodies were characterized using ELISA, Western blotting, and immunofluorescence techniques. The results obtained with polyclonal antibodies suggest the presence of specific proteins for each studied isolate and co-reactive immunochemical profiles among conserved components. Ten monoclonal antibody clones were obtained; mAb3 recognized 3 out of 4 samples studied. The results of this study may help standardize criteria for identifying and characterizing Acanthamoeba strains. Taken together, our results support the view that a set of features may help differentiate Acanthamoeba species and isolates.

  19. Nontypable Haemophilus influenzae Displays a Prevalent Surface Structure Molecular Pattern in Clinical Isolates

    Science.gov (United States)

    Mauro, Silvia; Hood, Derek W.; Viadas, Cristina; Calatayud, Laura; Morey, Pau; Servin, Alain; Liñares, Josefina; Oliver, Antonio; Bengoechea, José Antonio; Garmendia, Junkal

    2011-01-01

    Non-typable Haemophilus influenzae (NTHi) is a Gram negative pathogen that causes acute respiratory infections and is associated with the progression of chronic respiratory diseases. Previous studies have established the existence of a remarkable genetic variability among NTHi strains. In this study we show that, in spite of a high level of genetic heterogeneity, NTHi clinical isolates display a prevalent molecular feature, which could confer fitness during infectious processes. A total of 111 non-isogenic NTHi strains from an identical number of patients, isolated in two distinct geographical locations in the same period of time, were used to analyse nine genes encoding bacterial surface molecules, and revealed the existence of one highly prevalent molecular pattern (lgtF+, lic2A+, lic1D+, lic3A+, lic3B+, siaA−, lic2C+, ompP5+, oapA+) displayed by 94.6% of isolates. Such a genetic profile was associated with a higher bacterial resistance to serum mediated killing and enhanced adherence to human respiratory epithelial cells. PMID:21698169

  20. Assessment of biofilm formation in device-associated clinical bacterial isolates in a tertiary level hospital

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    Summaiya A Mulla

    2011-01-01

    Full Text Available Background: Biofilm formation is a developmental process with intercellular signals that regulate growth. Biofilms contaminate catheters, ventilators, and medical implants; they act as a source of disease for humans, animals, and plants. Aim: In this study we have done quantitative assessment of biofilm formation in device-associated clinical bacterial isolates in response to various concentrations of glucose in tryptic soya broth and with different incubation time. Materials and Methods: The study was carried out on 100 positive bacteriological cultures of medical devices, which were inserted in hospitalized patients. The bacterial isolates were processed as per microtitre plate method with tryptic soya broth alone and with varying concentrations of glucose and were observed in response to time. Results: Majority of catheter cultures were positive. Out of the total 100 bacterial isolates tested, 88 of them were biofilm formers. Incubation period of 16-20 h was found to be optimum for biofilm development. Conclusions: Availability of nutrition in the form of glucose enhances the biofilm formation by bacteria. Biofilm formation depends on adherence of bacteria to various surfaces. Time and availability of glucose are important factors for assessment of biofilm progress.

  1. Genetic and physiological studies of antibiotic resistance in a clinical isolate of Streptococcus faecalis

    International Nuclear Information System (INIS)

    Sharma, V.K.

    1987-01-01

    An erythromycin-sensitive clinical isolate of Streptococcus faecalis (CS-4B) generated intermediate-level erythromycin-resistant isolates ([CS-4B(S)] at a frequency of 4 x 10 -8 per cell. CS-4B(S) produces high-level erythromycin-resistant isolates [CS-4B(L)] at a very high frequency. The erythromycin-resistance is non-transferable, chromosomally located, and distinct from the well described erythromycin-resistance of the MLS type. The erythromycin-resistance of CS-4B(S) and CS-4B(L) is not due to an in vitro or in vivo alteration or inactivation of erythromycin. 14 C-erythromycin binds in vitro, as evaluated with sucrose gradients, to 70S ribosomes and 50S ribosomal subunits in CS-4B. Binding to CS-4B(L) ribosomes was barely detectable whereas CS-4B(S) ribosomes retained binding capacity. The binding studies on filter membranes revealed a substantial reduction of 14 C-erythromycin binding to CS-4B(S) ribosomes when compared to CS-4B ribosomes. The in vivo accumulation of 14 C-erythromycin in CS-4B and CS-4B(S) parallel the in vitro binding capacity of ribosomes indicating the apparent absence of a permeability barrier to erythromycin in CS-4B

  2. Genetic and physiological studies of antibiotic resistance in a clinical isolate of Streptococcus faecalis

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, V.K.

    1987-01-01

    An erythromycin-sensitive clinical isolate of Streptococcus faecalis (CS-4B) generated intermediate-level erythromycin-resistant isolates ((CS-4B(S)) at a frequency of 4 x 10/sup -8/ per cell. CS-4B(S) produces high-level erythromycin-resistant isolates (CS-4B(L)) at a very high frequency. The erythromycin-resistance is non-transferable, chromosomally located, and distinct from the well described erythromycin-resistance of the MLS type. The erythromycin-resistance of CS-4B(S) and CS-4B(L) is not due to an in vitro or in vivo alteration or inactivation of erythromycin. /sup 14/C-erythromycin binds in vitro, as evaluated with sucrose gradients, to 70S ribosomes and 50S ribosomal subunits in CS-4B. Binding to CS-4B(L) ribosomes was barely detectable whereas CS-4B(S) ribosomes retained binding capacity. The binding studies on filter membranes revealed a substantial reduction of /sup 14/C-erythromycin binding to CS-4B(S) ribosomes when compared to CS-4B ribosomes. The in vivo accumulation of /sup 14/C-erythromycin in CS-4B and CS-4B(S) parallel the in vitro binding capacity of ribosomes indicating the apparent absence of a permeability barrier to erythromycin in CS-4B.

  3. [Isolation of Sporothrix pallida complex in clinical and environmental samples from Chile].

    Science.gov (United States)

    Cruz Choappa, Rodrigo M; Vieille Oyarzo, Peggy I; Carvajal Silva, Laura C

    2014-01-01

    The isolation of S. pallida complex from medical samples and home garden soil of a patient in Chile is here in reported. Fungi of the Sporothrix schenckii complex can cause various infections. In Chile, the medical and environmental isolates of these this complex are rare. The aim of this study was to identify an unusual agent in a case of onychomycosis and to detect its presence in the patient's home garden. For this purpose, clinical samples were obtained by scraping the patient's subungueal first right toe nail as well as by taking soil samples from different areas of her home garden. Species identification was performed by morphophysiology and one of the strains isolated from the patient's toe nail was sent to CBS for molecular confirmation (14.062). S. pallida complex was identified both from the patient's toe nail and samples taken from her home garden. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  4. Nontypable Haemophilus influenzae displays a prevalent surface structure molecular pattern in clinical isolates.

    Directory of Open Access Journals (Sweden)

    Pau Martí-Lliteras

    Full Text Available Non-typable Haemophilus influenzae (NTHi is a gram negative pathogen that causes acute respiratory infections and is associated with the progression of chronic respiratory diseases. Previous studies have established the existence of a remarkable genetic variability among NTHi strains. In this study we show that, in spite of a high level of genetic heterogeneity, NTHi clinical isolates display a prevalent molecular feature, which could confer fitness during infectious processes. A total of 111 non-isogenic NTHi strains from an identical number of patients, isolated in two distinct geographical locations in the same period of time, were used to analyse nine genes encoding bacterial surface molecules, and revealed the existence of one highly prevalent molecular pattern (lgtF+, lic2A+, lic1D+, lic3A+, lic3B+, siaA-, lic2C+, ompP5+, oapA+ displayed by 94.6% of isolates. Such a genetic profile was associated with a higher bacterial resistance to serum mediated killing and enhanced adherence to human respiratory epithelial cells.

  5. Susceptibility profile of methicillin-resistantStaphylococcus aureusto linezolid in clinical isolates.

    Science.gov (United States)

    Shariq, Ali; Tanvir, Syed Bilal; Zaman, Atif; Khan, Salman; Anis, Armeena; Khan, Misha Aftab; Ahmed, Sumaira

    2017-01-01

    To determine the resistance and sensitivity pattern of methicillin-resistant Staphylococcus aureus (MRSA) isolates to linezolid (LZD) along with its prevalence in a tertiary care hospital of Karachi, Pakistan. A cross-sectional study was carried out. This study lasted for about 1 year. Prevalence and sensitivity of LZD, vancomycin, and oxacillin was tested against isolates of MRSA. Out of total 369 specimens 165 were found to be MRSA making the prevalence in our study 44.7%. All of the isolates which were tested positive for MRSA were susceptible to LZD and no resistance was noted when compared with previous studies performed in Europe and USA. Stringent implementation of infection control measures along with screening for resistance in patients on prolonged LZD therapy or who previously went under LZD therapy should be performed, coupled with judicious usage of the aforementioned antibiotic should be undertaken, as sufficient data is not available at this point for the clinical spectrum of LZD resistant S. aureus, antimicrobial resistance.

  6. CHARACTERISTICS OF ADHESIVE PROPERTIES OF LACTOBACILLUS - CLINICAL ISOLATES AND COMPONENTS OF BIOLOGICAL PRODUCTS

    Directory of Open Access Journals (Sweden)

    Lavryk G.

    2015-05-01

    Full Text Available Lactobacilli detected in all biotopes of digestive tract, starting from the mouth and ending with the colon, is the dominant flora of vaginal biotope. Their adhesiveness to epithelial cells leads to survive in conditions of microorganism biotopes and to form biofilm, thus mediating passive antagonism against conditionally pathogenic bacteria. Colonization resistance provides a set of mechanisms that provide individual anatomical stability and normal microflora. It is experimentally confirmed that lactobacilli provide biotopes colonization resistance of the human body due to competitive inhibition and coagregation of allochthonous microorganisms. It is important to consider the fact that probiotics should not compete with autochthonous microflora, which is always more physiological for each individual than most valuable exogenous bacteria, even with the greatest potential beneficial properties. The probiotic activity should be directed to the main target bacterial therapy, which is to restore physiological ecological community. The aim of research was to compare the adhesive properties of lactobacilli - clinical isolates of probiotic preparations and ingredients to the buccal epithelium cells and erythrocytes 0 (1 of the blood group system AB0 person. Materials and methods. The object of the research were clinical strains of Lactobacillus spp. selected from the mouth, intestines, vagina healthy people. At the the species identification of lactic acid bacteria were taken into account morphological and cultural properties, aerotolerance. The carbohydrate profile was determined using the test system API-50SN L (Bio-Merieux, lack of catalase activity. The ability of allocated bacteria to adhesion were observed in erythrocytes 0 (1 blood and buccal epithelium cells by human Brilis VI and oth. For comparison were used probiotic strains L. rlantarum 8PA3, L.acidophilus KS 400, Lactobacillus reuteri DSM 17938. The effectiveness of adhesion was assessed

  7. Periventricular lesions and MS diagnostic criteria in young adults with typical clinically isolated syndromes.

    Science.gov (United States)

    Brownlee, Wallace J; Miszkiel, Katherine A; Altmann, Daniel R; Ciccarelli, Olga; Miller, David H

    2017-06-01

    In patients who present with a clinically isolated syndrome (CIS), whose features are suggestive of multiple sclerosis (MS), fulfilling McDonald 2010 magnetic resonance imaging (MRI) criteria for dissemination in space (DIS) and dissemination in time (DIT) enables a diagnosis of MS. While ⩾1 periventricular lesion is included in the 2010 DIS criteria, earlier McDonald criteria required ⩾3 periventricular lesions to confirm DIS and recent Magnetic Resonance Imaging in Multiple Sclerosis (MAGNIMS)-recommended DIS criteria also require ⩾3 lesions. We investigated the effect of varying the required number of periventricular lesions and found that the best combination of specificity and sensitivity for clinically definite MS was seen for ⩾1 periventricular lesion using both the McDonald 2010 and MAGNIMS 2016 criteria.

  8. Whole Genome Sequence of the Heterozygous Clinical Isolate Candida krusei 81-B-5

    Directory of Open Access Journals (Sweden)

    Christina A. Cuomo

    2017-09-01

    Full Text Available Candida krusei is a diploid, heterozygous yeast that is an opportunistic fungal pathogen in immunocompromised patients. This species also is utilized for fermenting cocoa beans during chocolate production. One major concern in the clinical setting is the innate resistance of this species to the most commonly used antifungal drug fluconazole. Here, we report a high-quality genome sequence and assembly for the first clinical isolate of C. krusei, strain 81-B-5, into 11 scaffolds generated with PacBio sequencing technology. Gene annotation and comparative analysis revealed a unique profile of transporters that could play a role in drug resistance or adaptation to different environments. In addition, we show that, while 82% of the genome is highly heterozygous, a 2.0 Mb region of the largest scaffold has undergone loss of heterozygosity. This genome will serve as a reference for further genetic studies of this pathogen.

  9. Antifungal susceptibility testing of vaginal candida isolates: the broth microdilution method

    Directory of Open Access Journals (Sweden)

    Mahmoudi Rad M

    2010-02-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Vulvovaginal candidiasis is a common mucosal infection among immunocompetent, healthy women, and is caused by opportunistic yeasts that belong to genus Candida. In this study, we isolated and identified the Candida species in the vagina of patients who admitted in Gynecology Department of Mahdieh Hospital in Tehran, Iran to evaluate the in vitro activities of fluconazole, miconazole, itraconazole and flucytosine against 191 clinical Candida isolates by the NCCLS microdilution method."n"nMethods: 191 Candida were isolated from vaginal secretions and identified with conventional mycological methods in the diagnosis of Candida species. The identity of all strains was confirmed genotypically by multiplex PCR. In vitro susceptibility testing of vaginal Candida isolates was performed by the NCCLS broth microdilution method. The results were read at 48 h."n"nResults: Most C. albicans isolates (>90% were sensitive in vitro to the antifungal agents tested. Most C. glabrata isolates showed sensitivity to miconazole and then flucytosine while they were more resistant to Itraconazole and fluconazole. Many isolates of C. tropicalis were susceptible to miconazole and then fluconazole. They showed a little resistance to

  10. Novel Aminoglycoside Resistance Transposons and Transposon-Derived Circular Forms Detected in Carbapenem-Resistant Acinetobacter baumannii Clinical Isolates

    Science.gov (United States)

    Dwibedi, Chinmay Kumar; Sjöström, Karin; Edquist, Petra; Wai, Sun Nyunt; Uhlin, Bernt Eric

    2016-01-01

    Acinetobacter baumannii has emerged as an important opportunistic pathogen equipped with a growing number of antibiotic resistance genes. Our study investigated the molecular epidemiology and antibiotic resistance features of 28 consecutive carbapenem-resistant clinical isolates of A. baumannii collected throughout Sweden in 2012 and 2013. The isolates mainly belonged to clonal complexes (CCs) with an extensive international distribution, such as CC2 (n = 16) and CC25 (n = 7). Resistance to carbapenems was related to blaOXA-23 (20 isolates), blaOXA-24/40-like (6 isolates), blaOXA-467 (1 isolate), and ISAba1-blaOXA-69 (1 isolate). Ceftazidime resistance was associated with blaPER-7 in the CC25 isolates. Two classical point mutations were responsible for resistance to quinolones in all the isolates. Isolates with high levels of resistance to aminoglycosides carried the 16S rRNA methylase armA gene. The isolates also carried a variety of genes encoding aminoglycoside-modifying enzymes. Several novel structures involved in aminoglycoside resistance were identified, including Tn6279, ΔTn6279, Ab-ST3-aadB, and different assemblies of Tn6020 and TnaphA6. Importantly, a number of circular forms related to the IS26 or ISAba125 composite transposons were detected. The frequent occurrence of these circular forms in the populations of several isolates indicates a potential role of these circular forms in the dissemination of antibiotic resistance genes. PMID:26824943

  11. Screening for streptomycin resistance-conferring mutations in Mycobacterium tuberculosis clinical isolates from Poland.

    Science.gov (United States)

    Jagielski, Tomasz; Ignatowska, Helena; Bakuła, Zofia; Dziewit, Łukasz; Napiórkowska, Agnieszka; Augustynowicz-Kopeć, Ewa; Zwolska, Zofia; Bielecki, Jacek

    2014-01-01

    Currently, mutations in three genes, namely rrs, rpsL, and gidB, encoding 16S rRNA, ribosomal protein S12, and 16S rRNA-specific methyltransferase, respectively, are considered to be involved in conferring resistance to streptomycin (STR) in Mycobacterium tuberculosis. The aim of this study was to investigate the spectrum and frequency of these mutations in M. tuberculosis clinical isolates, both resistant and susceptible to STR. Sixty-four M. tuberculosis isolates recovered from as many TB patients from Poland in 2004 were included in the study. Within the sample were 50 multidrug-resistant (32 STR-resistant and 18 STR-susceptible) and 14 pan-susceptible isolates. Preliminary testing for STR resistance was performed with the 1% proportion method. The MICs of STR were determined by the Etest method. Mutation profiling was carried out by amplifying and sequencing the entire rrs, rpsL, and gidB genes. Non-synonymous mutations in either rrs or rpsL gene were detected in 23 (71.9%) of the STR-resistant and none of the STR-susceptible isolates. Mutations in the gidB gene were distributed among 12 (37.5%) STR-resistant and 13 (40.6%) STR-susceptible isolates. Four (12.5%) STR-resistant isolates were wild-type at all three loci examined. None of the rrs, rpsL or gidB mutations could be linked to low, intermediate or high level of STR resistance. In accordance with previous findings, the gidB 47T→G (L16R) mutation was associated with the Latin American-Mediterranean genotype family, whereas 276A→C (E92D) and 615A→G (A205A) mutations of the gidB gene were associated with the Beijing lineage. The study underlines the usefulness of rrs and rpsL mutations as molecular markers for STR resistance yet not indicative of its level. The gidB polymorphisms can serve as phylogenetic markers.

  12. Is Penicillin plus Gentamicin Synergistic against Clinical Group B Streptococcus isolates?: A in-vitro Study.

    Directory of Open Access Journals (Sweden)

    Corinne Ruppen

    2016-10-01

    Full Text Available Group B Streptococcus (GBS is increasingly causing invasive infections in nonpregnant adults. Elderly patients and those with comorbidities are at increased risk. On the basis of previous studies focusing on neonatal infections, penicillin plus gentamicin is recommended for infective endocarditis (IE and periprosthetic joint infections (PJI in adults. The purpose of this study was to investigate whether a synergism with penicillin and gentamicin is present in GBS isolates that caused IE and PJI. We used 5 GBS isolates, two clinical strains and three control strains, including one displaying high-level gentamicin resistance (HLGR. The results from the checkerboard and time-kill assays (TKAs were compared. For TKAs, antibiotic concentrations for penicillin were 0.048 and 0.2 mg/L, and for gentamicin 4 mg/L or 12.5 mg/L. In the checkerboard assay, the median fractional inhibitory concentration indices (FICIs of all isolates indicated indifference. TKAs for all isolates failed to demonstrate synergism with penicillin 0.048 or 0.2 mg/L, irrespective of gentamicin concentrations used. Rapid killing was seen with penicillin 0.048 mg/L plus either 4 mg/L or 12.5 mg/L gentamicin, from 2 h up to 8 h hours after antibiotic exposure. TKAs with penicillin 0.2 mg/L decreased the starting inoculum below the limit of quantification within 4 h to 6 h, irrespective of the addition of gentamicin. Fast killing was seen with penicillin 0.2 mg/L plus 12.5 mg/L gentamicin within the first 2 h. Our in vitro results indicate that the addition of gentamicin to penicillin contributes to faster killing at low penicillin concentrations, but only within the first few hours. Twenty-four hours after antibiotic exposure, PEN alone was bactericidal and synergism was not seen.

  13. High-throughput genome sequencing of two Listeria monocytogenes clinical isolates during a large foodborne outbreak

    Directory of Open Access Journals (Sweden)

    Trout-Yakel Keri M

    2010-02-01

    Full Text Available Abstract Background A large, multi-province outbreak of listeriosis associated with ready-to-eat meat products contaminated with Listeria monocytogenes serotype 1/2a occurred in Canada in 2008. Subtyping of outbreak-associated isolates using pulsed-field gel electrophoresis (PFGE revealed two similar but distinct AscI PFGE patterns. High-throughput pyrosequencing of two L. monocytogenes isolates was used to rapidly provide the genome sequence of the primary outbreak strain and to investigate the extent of genetic diversity associated with a change of a single restriction enzyme fragment during PFGE. Results The chromosomes were collinear, but differences included 28 single nucleotide polymorphisms (SNPs and three indels, including a 33 kbp prophage that accounted for the observed difference in AscI PFGE patterns. The distribution of these traits was assessed within further clinical, environmental and food isolates associated with the outbreak, and this comparison indicated that three distinct, but highly related strains may have been involved in this nationwide outbreak. Notably, these two isolates were found to harbor a 50 kbp putative mobile genomic island encoding translocation and efflux functions that has not been observed in other Listeria genomes. Conclusions High-throughput genome sequencing provided a more detailed real-time assessment of genetic traits characteristic of the outbreak strains than could be achieved with routine subtyping methods. This study confirms that the latest generation of DNA sequencing technologies can be applied during high priority public health events, and laboratories need to prepare for this inevitability and assess how to properly analyze and interpret whole genome sequences in the context of molecular epidemiology.

  14. Molecular mechanisms associated with Fluconazole resistance in clinical Candida albicans isolates from India.

    Science.gov (United States)

    Mane, Arati; Vidhate, Pallavi; Kusro, Chanchal; Waman, Vaishali; Saxena, Vandana; Kulkarni-Kale, Urmila; Risbud, Arun

    2016-02-01

    Resistance to azole antifungals is a significant problem in Candida albicans. An understanding of resistance at molecular level is essential for the development of strategies to tackle resistance and rationale design of newer antifungals and target-based molecular approaches. This study presents the first evaluation of molecular mechanisms associated with fluconazole resistance in clinical C.albicans isolates from India. Target site (ERG11) alterations were determined by DNA sequencing, whereas real-time PCRs were performed to quantify target and efflux pump genes (CDR1, CDR2, MDR1) in 87 [Fluconazole susceptible (n = 30), susceptible-dose dependent (n = 30) and resistant (n = 27)] C.albicans isolates. Cross-resistance to fluconazole, ketoconazole and itraconazole was observed in 74.1% isolates. Six amino acid substitutions were identified, including 4 (E116D, F145L, E226D, I437V) previously reported ones and 2 (P406L, Q474H) new ones. CDR1 over-expression was seen in 77.7% resistant isolates. CDR2 was exclusively expressed with CDR1 and their concomitant over-expression was associated with azole cross-resistance. MDR1 and ERG11 over-expression did not seem to be associated with resistance. Our results show that drug efflux mediated by Adenosine-5'-triphosphate (ATP)-binding cassette transporters, especially CDR1 is the predominant mechanism of fluconazole resistance and azole cross-resistance in C. albicans and indicate the need for research directed towards developing strategies to tackle efflux mediated resistance to salvage azoles. © 2015 Blackwell Verlag GmbH.

  15. Helicobacter pylori HopE and HopV porins present scarce expression among clinical isolates

    Science.gov (United States)

    Lienlaf, Maritza; Morales, Juan Pablo; Díaz, María Inés; Díaz, Rodrigo; Bruce, Elsa; Siegel, Freddy; León, Gloria; Harris, Paul R; Venegas, Alejandro

    2010-01-01

    AIM: To evaluate how widely Helicobacter pylori (H. pylori) HopE and HopV porins are expressed among Chilean isolates and how seroprevalent they are among infected patients in Chile. METHODS: H. pylori hopE and hopV genes derived from strain CHCTX-1 were cloned by polymerase chain reaction (PCR), sequenced and expressed in Escherichia coli AD494 (DE3). Gel-purified porins were used to prepare polyclonal antibodies. The presence of both genes was tested by PCR in a collection of H. pylori clinical isolates and their expression was detected in lysates by immunoblotting. Immune responses against HopE, HopV and other H. pylori antigens in sera from infected and non-infected patients were tested by Western blotting using these sera as first antibody on recombinant H. pylori antigens. RESULTS: PCR and Western blotting assays revealed that 60 and 82 out of 130 Chilean isolates carried hopE and hopV genes, respectively, but only 16 and 9, respectively, expressed these porins. IgG serum immunoreactivity evaluation of 69 H. pylori-infected patients revealed that HopE and HopV were infrequently recognized (8.7% and 10.1% respectively) compared to H. pylori VacA (68.1%) and CagA (59.5%) antigens. Similar values were detected for IgA serum immunoreactivity against HopE (11.6%) and HopV (10.5%) although lower values for VacA (42%) and CagA (17.4%) were obtained when compared to the IgG response. CONCLUSION: A scarce expression of HopE and HopV among Chilean isolates was found, in agreement with the infrequent seroconversion against these antigens when tested in infected Chilean patients. PMID:20082477

  16. Identification, distribution, and expression of novel genes in 10 clinical isolates of nontypeable Haemophilus influenzae.

    Science.gov (United States)

    Shen, Kai; Antalis, Patricia; Gladitz, John; Sayeed, Sameera; Ahmed, Azad; Yu, Shujun; Hayes, Jay; Johnson, Sandra; Dice, Bethany; Dopico, Richard; Keefe, Randy; Janto, Benjamin; Chong, William; Goodwin, Joseph; Wadowsky, Robert M; Erdos, Geza; Post, J Christopher; Ehrlich, Garth D; Hu, Fen Z

    2005-06-01

    We hypothesize that Haemophilus influenzae, as a species, possesses a much greater number of genes than that found in any single H. influenzae genome. This supragenome is distributed throughout naturally occurring infectious populations, and new strains arise through autocompetence and autotransformation systems. The effect is that H. influenzae populations can readily adapt to environmental stressors. The supragenome hypothesis predicts that significant differences exist between and among the genomes of individual infectious strains of nontypeable H. influenzae (NTHi). To test this prediction, we obtained 10 low-passage NTHi clinical isolates from the middle ear effusions of patients with chronic otitis media. DNA sequencing was performed with 771 clones chosen at random from a pooled genomic library. Homology searching demonstrated that approximately 10% of these clones were novel compared to the H. influenzae Rd KW20 genome, and most of them did not match any DNA sequence in GenBank. Amino acid homology searches using hypothetical translations of the open reading frames revealed homologies to a variety of proteins, including bacterial virulence factors not previously identified in the NTHi isolates. The distribution and expression of 53 of these genes among the 10 strains were determined by PCR- and reverse transcription PCR-based analyses. These unique genes were nonuniformly distributed among the 10 isolates, and transcription of these genes in planktonic cultures was detected in 50% (177 of 352) of the occurrences. All of the novel sequences were transcribed in one or more of the NTHi isolates. Seventeen percent (9 of 53) of the novel genes were identified in all 10 NTHi strains, with each of the remaining 44 being present in only a subset of the strains. These genic distribution analyses were more effective as a strain discrimination tool than either multilocus sequence typing or 23S ribosomal gene typing methods.

  17. Molecular Characterization and Panton-Valentine Leucocidin Typing of Community-Acquired Methicillin-Sensitive Staphylococcus aureus Clinical Isolates

    Science.gov (United States)

    Sloan, Tim; Kearns, Angela M.; James, Richard

    2012-01-01

    Limited comprehensive molecular typing data exist currently for Panton-Valentine leucocidin (PVL)-positive, methicillin-sensitive Staphylococcus aureus (PVL-MSSA) clinical isolates. Characterization of PVL-MSSA isolates by multilocus sequence typing (MLST) and spa typing in this study showed a genetic similarity to PVL-positive, methicillin-resistant S. aureus (PVL-MRSA) strains, although three novel spa types and a novel MLST (ST1518) were detected. Furthermore, the detection of PVL phages and haplotypes in PVL-MSSA identical to those previously found in PVL-MRSA isolates highlights the role these strains may play as precursors of emerging lineages of clinical significance. PMID:22718937

  18. Isolated brachydactyly type E and idiopathic pancreatitis in a patient presenting to a lipid disorders clinic.

    Science.gov (United States)

    Page, Michael M; Hooper, Amanda J; Glendenning, Paul; Burnett, John R

    2017-04-06

    An 18-year-old female tertiary student was referred to a lipid clinic with hypertriglyceridaemia discovered after presentation with acute pancreatitis. The patient's only medication was l-thyroxine for treatment of hypothyroidism. She was overweight, normotensive, with unremarkable facies. However, she had hypermobile hand joints and brachydactyly resulting in loss of left 3-5 and right 4 and 5 knuckle definitions. Radiography revealed shortening of metacarpals 3-5 on the left and 4 and 5 on the right. Her mother had similar skeletal changes, consistent with a dominant mode of inheritance. Abnormally short digits involving the metacarpals, classified as brachydactyly type E, can be isolated or occur as part of a syndrome. Turner syndrome, Albright hereditary osteodystrophy, hypertension with brachydactyly, chromosome 2q37 microdeletion and PTHLH mutations were excluded following clinical, biochemical and genetic testing. No specific treatment was required. Genetic testing for isolated and syndromic forms of brachydactyly facilitates family screening and prepregnancy counselling. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. The antibacterial activity of some essential oils against clinical isolates of Acinetobacter baumannii

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    Mohaddese Mahboubi

    2014-10-01

    Full Text Available Acinetobacter baumannii is categorized as a red alert pathogen that is increasingly associated with a high mortality rate in infected patients due to its resistance to extensive antibiotics. In this study, we evaluated the antibacterial activities of some essential oils (Oliveria decumbens, Pelargonium graveolens, Eugenia caryophyllata, Ziziphora tenuir and Trachyspermum copticum oils against 32 clinical isolates of A. baumannii. The antibacterial evaluations and chemical composition of essential oils was determined. Thymol, eugenol, -terpineol, -citronellol and thymol were the chief portions of T. copticum, E. caryophyllata, Z. tenuir, O. decumbens and P. graveolens oils, respectively. The MIC values of oils against these clinical isolates revealed the three subsets of oils including 1- T. copticum, E. caryophyllata and O. decumbens, 2- Z. tenuir and 3- P. graveolens oils. These oils showed the synergistic activity with amikacin, the lower Fractional Inhibitory Concentration Index (FICI was for P. graveolens oil (0.23 and the higher FICI was for E. caryophyllata (0.325.

  20. Molecular basis for different levels of tet(M) expression in Streptococcus pneumoniae clinical isolates.

    Science.gov (United States)

    Grohs, Patrick; Trieu-Cuot, Patrick; Podglajen, Isabelle; Grondin, Sophie; Firon, Arnaud; Poyart, Claire; Varon, Emmanuelle; Gutmann, Laurent

    2012-10-01

    Seventy-four unrelated clinical isolates of Streptococcus pneumoniae harboring the tet(M) gene were studied. Seven strains with low tetracycline (Tc) MICs (0.25 to 0.5 μg/ml) were found to harbor truncated tet(M) alleles that were inactivated by different frameshift mutations. In contrast, five strains bore deletions in the tet(M) promoter region, among which four displayed increased Tc MICs (16 to 64 μg/ml). The same promoter mutations were detected in Tc-resistant mutants selected in vitro from various susceptible strains. Sequence analysis revealed that these deletions might impede the formation of the transcriptional attenuator located immediately upstream of tet(M). Expression in Enterococcus faecalis of a tet(M) reporter gene transcribed from these promoter mutants conferred a level of Tc resistance similar to that observed in the parental S. pneumoniae strains. These results show that different levels of Tc susceptibility found in clinical isolates of S. pneumoniae can be explained by frameshift mutations within tet(M) and by alterations of the upstream transcriptional attenuator.

  1. In vitro antibacterial activity of onion (allium cepa) against clinical isolates of vibrio cholera

    International Nuclear Information System (INIS)

    Hannan, A.; Humayun, T.; Hussain, M.B.; Yasir, M.; Sikandar, S.

    2010-01-01

    Background: Cholera is a major public health problem in developing countries of the world. Bacterial resistance, lack of surveillance data and proper microbiological facilities are major problems regarding diagnosis of cholera. The spread of microbial drug resistance is a global public health challenge that results in increased illness and death rate. Newer antimicrobials or agents are urgently required to overcome this problem. This work was therefore done to investigate the antimicrobial potential of onion against thirty-three clinical isolates of Vibrio cholera. Methods: The extract was prepared by reflux extraction method. Antibacterial screening of clinical isolates of V. cholerae was done by agar well diffusion method. Agar dilution method was used to assess the Minimum Inhibitory Concentration (MIC). Results: All tested strains of V. cholerae were sensitive to onion (Allium cepa) extracts of two types (purple and yellow). Purple type of extract had MIC range of 19.2-21.6 mg/ml. The extract of yellow type onion had an MIC range of 66-68.4 mg/ml. Conclusion: The results indicated that onion (Allium cepa) has an inhibitory effect on V. cholerae. Keeping in view the anti-bacterial activity of this compound can be exploited as a therapeutic agent in an animal model. This finding is a positive point for further investigation of this herb of traditional medicine. (author)

  2. Genotyping of Acanthamoeba isolates and clinical characteristics of patients with Acanthamoeba keratitis in China.

    Science.gov (United States)

    Zhao, Ge; Sun, Shiying; Zhao, Jing; Xie, Lixin

    2010-04-01

    Acanthamoeba keratitis (AK) is a sight-threatening corneal infection, the epidemiology of which is related to the specific genotype of Acanthamoeba. In this study, the genotypes of 14 Acanthamoeba isolates, each from a patient with AK, were identified according to the highly variable DF3 region in the 18S rRNA gene at Shandong Eye Institute, PR China, from 2000 to 2009, and the clinical characteristics of these patients were analysed. All 14 amoebae were genotype T4, representing nine different DF3 sequence types, seven of which were newly identified. Cornea infestation was the main risk factor for these 14 AK patients. Amoebic cysts could be detected in all corneal scrapes. Corneal ulcers were located mainly at the corneal centre, accompanied by eye pain, and some appeared with a Wessely ring. Surgery was carried out on all patients. Acanthamoeba genotypes T4/26 and T4/27 were found to cause a more severe keratitis, whilst the others showed no significant differences in clinical characteristics. In conclusion, the majority of the keratitis-causing Acanthamoeba isolates were genotype T4, with Acanthamoeba genotypes T4/26 and T4/27 from PR China causing a more severe keratitis.

  3. Opa typing of Neisseria gonorrhoeae strains isolated from patients attending sexually transmitted disease clinics in China.

    Science.gov (United States)

    Chen, Qiang; Yin, Yue-Ping; Dai, Xiu-Qin; Yu, Yan-Hua; Wang, Hong-Chun; Zhu, Bang-Yong; Gao, Xing; Chen, Xiang-Sheng

    2007-12-01

    Gonorrhoea has been one of the most common sexually transmitted diseases (STDs) in China. A clear understanding of its transmission dynamics is important in formulating prevention and control measures. To investigate the distribution of opa types in patients attending at STD clinics in China and to evaluate the concordance between epidemiologic data and opa-typing results. Opa typing was conducted for 330 Neisseria gonorrhoeae strains isolated from the patients at 4 STDs clinics in China, and the epidemiologic data were collected as well. A total of 309 opa types were detected from the 330 isolates. Two hundred ninety-two opa types were unique, and 17 opa types were found in more than 1 patient. Opa typing confirmed all 9 sexual links that were revealed by epidemiologic information and further identified 9 opa clusters and 8 similar pairs. Opa typing is a discriminatory tool that can be used in epidemiologic studies on gonococcal infections. This technique is more powerful than epidemiologic data to identify sexual links and improve our understanding of the transmission dynamics of gonorrhoea.

  4. Degenerate primer MOB typing of multiresistant clinical isolates of E. coli uncovers new plasmid backbones.

    Science.gov (United States)

    Garcillán-Barcia, M Pilar; Ruiz del Castillo, Belén; Alvarado, Andrés; de la Cruz, Fernando; Martínez-Martínez, Luis

    2015-01-01

    Degenerate Primer MOB Typing is a PCR-based protocol for the classification of γ-proteobacterial transmissible plasmids in five phylogenetic relaxase MOB families. It was applied to a multiresistant E. coli collection, previously characterized by PCR-based replicon-typing, in order to compare both methods. Plasmids from 32 clinical isolates of multiresistant E. coli (19 extended spectrum beta-lactamase producers and 13 non producers) and their transconjugants were analyzed. A total of 95 relaxases were detected, at least one per isolate, underscoring the high potential of these strains for antibiotic-resistance transmission. MOBP12 and MOBF12 plasmids were the most abundant. Most MOB subfamilies detected were present in both subsets of the collection, indicating a shared mobilome among multiresistant E. coli. The plasmid profile obtained by both methods was compared, which provided useful data upon which decisions related to the implementation of detection methods in the clinic could be based. The phylogenetic depth at which replicon and MOB-typing classify plasmids is different. While replicon-typing aims at plasmid replication regions with non-degenerate primers, MOB-typing classifies plasmids into relaxase subfamilies using degenerate primers. As a result, MOB-typing provides a deeper phylogenetic depth than replicon-typing and new plasmid groups are uncovered. Significantly, MOB typing identified 17 plasmids and an integrative and conjugative element, which were not detected by replicon-typing. Four of these backbones were different from previously reported elements. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Neutropenia exacerbates infection by Acinetobacter baumannii clinical isolates in a murine wound model

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    Laryssa eGrguric-Smith

    2015-10-01

    Full Text Available The Gram negative coccobacillus Acinetobacter baumannii has become an increasingly prevalent cause of hospital-acquired infections in recent years. The majority of clinical A. baumannii isolates display high-level resistance to antimicrobials, which severely compromises our capacity to care for patients with A. baumannii disease. Neutrophils are of major importance in the host defense against microbial infections. However, the contribution of these cells of innate immunity in host resistance to cutaneous A. baumannii infection has not been directly investigated. Hence, we hypothesized that depletion of neutrophils increases severity of bacterial disease in an experimental A. baumannii murine wound model. In this study, the anti-Ly-6G monoclonal antibody (mAb, 1A8, was used to generate neutropenic mice and the pathogenesis of several A. baumannii clinical isolates on wounded cutaneous tissue was investigated. We demonstrated that neutrophil depletion enhances bacterial burden using colony forming unit determinations. Also, mAb 1A8 reduces global measurements of wound healing in A. baumannii-infected animals. Interestingly, histological analysis of cutaneous tissue excised from A. baumannii-infected animals treated with mAb 1A8 displays enhanced collagen deposition. Furthermore, neutropenia and A. baumannii infection alter pro-inflammatory cytokine release leading to severe microbial disease. Our findings provide a better understanding of the impact of these innate immune cells in controlling A. baumannii skin infections.

  6. Assessment of Early Cognitive Impairment in Patients with Clinically Isolated Syndromes and Multiple Sclerosis

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    Leyla Baysal Kıraç

    2014-01-01

    Full Text Available Objective. The aim of our study was to investigate the frequency and pattern of cognitive impairment in patients with clinically isolated syndromes and definite diagnosis of multiple sclerosis within the last 2 years. Methods. We assessed the cognitive status of 46 patients aged 18–49 years with clinically isolated syndromes or definite diagnosis of multiple sclerosis who have onset of their symptoms within the last 2 years. Patients were matched with 40 healthy participants for age, sex, and educational level. Neuropsychological assessment was performed by stroop test, paced auditory serial addition test (PASAT, controlled oral word association test (COWAT, clock drawing test, trail making test (TMT, faces symbol test (FST. Hamilton Depression Scale and Modified Fatigue Impact Scale were used to quantify the severity of any depression and fatigue the subjects might suffer. Results. 19.6% of early MS/CIS group failed at 4 and more tests and had significant cognitive impairment focused on attention, executive functions, memory, and learning. No significant relationship was found between cognitive impairment and disability and fatigue scores. Discussion. Cognitive impairment can be present from the earliest stage of multiple sclerosis. It should be considered among the main manifestations of MS even in the earliest stages of the disease.

  7. Antimicrobial susceptibility patterns and CTX-M β-lactamase producing clinical isolates from burn patients in Islamabad, Pakistan

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    Mubbashir Hussain

    2017-08-01

    Full Text Available Objective: To evaluate the prevalence of extended spectrum beta-lactamases (ESBL in clinical isolates from burn patients using phenotypic and genotypic analyses. Methods: During 2015–2016, a total of 126 samples were collected at a tertiary care hospital, Islamabad. Antibiotic sensitivity and ESBL prevalence were evaluated according to the Clinical Laboratory and Standards Institute, and molecular analysis of the CTX-M type ESBL gene was performed in 225 bacterial isolates from these samples. Results: The most prevalent bacterial species were Escherichia coli (28.4%, Pseudomonas aeruginosa (22.2%, Staphylococcus aureus (19.6%, Klebsiella pneumoniae (16.4%, and coagulase-negative staphylococci (13.3%. Of the 225 bacterial isolates, 89 (39.5% were found to be ESBL producers. The isolates were highly susceptible to meropenem (88% and imipenem (84%, followed by the aminoglycoside amikacin (81%. Molecular epidemiology of the ESBL isolates indicated 19% prevalence of CTX-M. Resistance to antibiotics was exhibited by 28% isolates. Conclusions: In the present study, bacteria such as P. aeruginosa, K. pneumoniae, S. aureus, and E. coli isolated from burn patients exhibited resistance to one or more antibiotics and produced large amounts of ESBL. Further studies are needed to investigate the virulence and epidemiology of CTX-M type ESBL in clinical isolates from burn patients.

  8. Enhancing DNA electro-transformation efficiency on a clinical Staphylococcus capitis isolate.

    Science.gov (United States)

    Cui, Bintao; Smooker, Peter M; Rouch, Duncan A; Deighton, Margaret A

    2015-02-01

    Clinical staphylococcus isolates possess a stronger restriction-modification (RM) barrier than laboratory strains. Clinical isolates are therefore more resistant to acceptance of foreign genetic material than laboratory strains, as their restriction systems more readily recognize and destroy foreign DNA. This stronger barrier consequently restricts genetic studies to a small number of domestic strains that are capable of accepting foreign DNA. In this study, an isolate of Staphylococcus capitis, obtained from the blood of a very low birth-weight baby, was transformed with a shuttle vector, pBT2. Optimal conditions for electro-transformation were as follows: cells were harvested at mid-log phase, electro-competent cells were prepared; cells were pre-treated at 55°C for 1min; 3μg of plasmid DNA was mixed with 70-80μL of competent cells (3-4×10(10)cells/mL) at 20°C in 0.5M sucrose, 10% glycerol; and electroporation was conducted using 2.1kV/cm field strength with a 0.1cm gap. Compared to the conventional method, which involves DNA electroporation of Staphylococcus aureus RN4220 as an intermediate strain to overcome the restriction barrier, our proposed approach exhibits a higher level (3 log10 units) of transformation efficiency. Heat treatment was used to temporarily inactivate the recipient RM barrier. Other important parameters contributing to improved electro-transformation efficiency were growth stage for cell harvesting, the quantity of DNA, the transformation temperature and field strength. The approach described here may facilitate genetic manipulations of this opportunistic pathogen. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Biofilm formation by Staphylococcus aureus isolates from a dental clinic in Konya, Turkey.

    Science.gov (United States)

    Torlak, Emrah; Korkut, Emre; Uncu, Ali T; Şener, Yağmur

    The ability of Staphylococcus aureus to form biofilm is considered to be a major virulence factor influencing its survival and persistence in both the environment and the host. Biofilm formation in S. aureus is most frequently associated with production of polysaccharide intercellular adhesion by ica operon-encoded enzymes. The present work aimed at evaluating the in vitro biofilm production and presence of the icaA and icaD genes in S. aureus isolates from a dental clinic in Konya, Turkey. The surfaces of inanimate objects were sampled over a period of six months. S. aureus isolates were subjected to Congo Red Agar (CRA) and crystal violet (CV) staining assays to evaluate their ability of biofilm production, while the presence of the icaA and icaD genes was determined by polymerase chain reaction. S. aureus contamination was detected in 13.2% of the environmental samples. All the 32 isolates were observed to be positive for both the icaA and icaD genes. Phenotypic evaluations revealed that CV staining assay is a more reliable alternative to CRA assay to determine biofilm formation ability. A high percentage of agreement (91%) was observed between the results from CV staining and ica genes' detection assays. Phenotypic and genotypic evaluations should be combined to detect biofilm formation in S. aureus. Our findings indicate that dental clinic environments should be considered as potential reservoir for biofilm-producing S. aureus and thus cross contamination. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Comparative genomics of Tunisian Leishmania major isolates causing human cutaneous leishmaniasis with contrasting clinical severity.

    Science.gov (United States)

    Ghouila, Amel; Guerfali, Fatma Z; Atri, Chiraz; Bali, Aymen; Attia, Hanene; Sghaier, Rabiaa M; Mkannez, Ghada; Dickens, Nicholas J; Laouini, Dhafer

    2017-06-01

    Zoonotic cutaneous leishmaniasis caused by Leishmania (L.) major parasites affects urban and suburban areas in the center and south of Tunisia where the disease is endemo-epidemic. Several cases were reported in human patients for which infection due to L. major induced lesions with a broad range of severity. However, very little is known about the mechanisms underlying this diversity. Our hypothesis is that parasite genomic variability could, in addition to the host immunological background, contribute to the intra-species clinical variability observed in patients and explain the lesion size differences observed in the experimental model. Based on several epidemiological, in vivo and in vitro experiments, we focused on two clinical isolates showing contrasted severity in patients and BALB/c experimental mice model. We used DNA-seq as a high-throughput technology to facilitate the identification of genetic variants with discriminating potential between both isolates. Our results demonstrate that various levels of heterogeneity could be found between both L. major isolates in terms of chromosome or gene copy number variation (CNV), and that the intra-species divergence could surprisingly be related to single nucleotide polymorphisms (SNPs) and Insertion/Deletion (InDels) events. Interestingly, we particularly focused here on genes affected by both types of variants and correlated them with the observed gene CNV. Whether these differences are sufficient to explain the severity in patients is obviously still open to debate, but we do believe that additional layers of -omic information is needed to complement the genomic screen in order to draw a more complete map of severity determinants. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Multi drug resistance in strong biofilm forming clinical isolates of Staphylococcus epidermidis

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    Gulcan Sahal

    2014-06-01

    Full Text Available Staphylococcus epidermidis which exists in healthy human skin as a commensal inhabitant is also an important pathogen forming biofilms on many surfaces and recently, increased resistance traits were suggested to be acquired in biofilm environments. In this study; clinical Prevalences, antibiotic resistances and biofilm formations of S. epidermidis strains were determined and comparison of all these findings with each other was carried out in order to take precautions against them and figure out if high biofilm forming S. epidermidis strains display multi drug resistance. According to our results; samples of wound and blood were the most S. epidermidis isolated clinical materials (40%; 35% and cardiothoracic surgery was the most S. epidermidis observed service unit. All of these strains were sensitive to vancomycin, however 65% of them showed resistance to all β-lactam antibiotics (Penicillin, Oxacillin, Amoxicilin / Clavulonic acid, used in this study and 60% of all S. epidermidis strains were found as multi drug resistant. When the results of strong biofilm forming S. epidermidis strains are examined; they were isolated from sample of blood and service unit of cardiovascular surgery in highest frequency and 80% of them were β-lactam resistant whereas 100% of them were multi drug resistant. One of these multi drug resistant strains which was resistant to maximum amount of different antimicrobial classes, was also observed as maximum biofilm forming strain among all the other S. epidermidis isolates. Multi drug resistance in strong biofilm forming strains shows that; biofilms play a role in antimicrobial resistance traits of S. epidermidis.

  12. Expression of the CDR1 efflux pump in clinical Candida albicans isolates is controlled by a negative regulatory element

    International Nuclear Information System (INIS)

    Gaur, Naseem Akhtar; Manoharlal, Raman; Saini, Preeti; Prasad, Tulika; Mukhopadhyay, Gauranga; Hoefer, Milan; Morschhaeuser, Joachim; Prasad, Rajendra

    2005-01-01

    Resistance to azole antifungal drugs in clinical isolates of the human fungal pathogen Candida albicans is often caused by constitutive overexpression of the CDR1 gene, which encodes a multidrug efflux pump of the ABC transporter superfamily. To understand the relevance of a recently identified negative regulatory element (NRE) in the CDR1 promoter for the control of CDR1 expression in the clinical scenario, we investigated the effect of mutation or deletion of the NRE on CDR1 expression in two matched pairs of azole-sensitive and resistant clinical isolates of C. albicans. Expression of GFP or lacZ reporter genes from the wild type CDR1 promoter was much higher in the azole-resistant C. albicans isolates than in the azole-susceptible isolates, reflecting the known differences in CDR1 expression in these strains. Deletion or mutation of the NRE resulted in enhanced reporter gene expression in azole-sensitive strains, but did not further increase the already high CDR1 promoter activity in the azole-resistant strains. In agreement with these findings, electrophoretic mobility shift assays showed a reduced binding to the NRE of nuclear extracts from the resistant C. albicans isolates as compared with extracts from the sensitive isolates. These results demonstrate that the NRE is involved in maintaining CDR1 expression at basal levels and that this repression is overcome in azole-resistant clinical C. albicans isolates, resulting in constitutive CDR1 overexpression and concomitant drug resistance

  13. Genome-scale metabolic modeling and in silico analysis of lipid accumulating yeast Candida tropicalis for dicarboxylic acid production.

    Science.gov (United States)

    Mishra, Pranjul; Park, Gyu-Yeon; Lakshmanan, Meiyappan; Lee, Hee-Seok; Lee, Hongweon; Chang, Matthew Wook; Ching, Chi Bun; Ahn, Jungoh; Lee, Dong-Yup

    2016-09-01

    Recently, the bio-production of α,ω-dicarboxylic acids (DCAs) has gained significant attention, which potentially leads to the replacement of the conventional petroleum-based products. In this regard, the lipid accumulating yeast Candida tropicalis, has been recognized as a promising microbial host for DCA biosynthesis: it possess the unique ω-oxidation pathway where the terminal carbon of α-fatty acids is oxidized to form DCAs with varying chain lengths. However, despite such industrial importance, its cellular physiology and lipid accumulation capability remain largely uncharacterized. Thus, it is imperative to better understand the metabolic behavior of this lipogenic yeast, which could be achieved by a systems biological approach. To this end, herein, we reconstructed the genome-scale metabolic model of C. tropicalis, iCT646, accounting for 646 unique genes, 945 metabolic reactions, and 712 metabolites. Initially, the comparative network analysis of iCT646 with other yeasts revealed several distinctive metabolic reactions, mainly within the amino acid and lipid metabolism including the ω-oxidation pathway. Constraints-based flux analysis was, then, employed to predict the in silico growth rates of C. tropicalis which are highly consistent with the cellular phenotype observed in glucose and xylose minimal media chemostat cultures. Subsequently, the lipid accumulation capability of C. tropicalis was explored in comparison with Saccharomyces cerevisiae, indicating that the formation of "citrate pyruvate cycle" is essential to the lipid accumulation in oleaginous yeasts. The in silico flux analysis also highlighted the enhanced ability of pentose phosphate pathway as NADPH source rather than malic enzyme during lipogenesis. Finally, iCT646 was successfully utilized to highlight the key directions of C. tropicalis strain design for the whole cell biotransformation application to produce long-chain DCAs from alkanes. Biotechnol. Bioeng. 2016;113: 1993-2004.

  14. Cytotoxic clinical isolates of Pseudomonas aeruginosa identified during the Steroids for Corneal Ulcers Trial show elevated resistance to fluoroquinolones.

    Science.gov (United States)

    Borkar, Durga S; Acharya, Nisha R; Leong, Chelsia; Lalitha, Prajna; Srinivasan, Muthiah; Oldenburg, Catherine E; Cevallos, Vicky; Lietman, Thomas M; Evans, David J; Fleiszig, Suzanne M J

    2014-04-24

    To determine the relationship between type three secretion genotype and fluoroquinolone resistance for P. aeruginosa strains isolated from microbial keratitis during the Steroids for Corneal Ulcers Trial (SCUT) and for two laboratory strains, PA103 and PAO1. Confirmed P. aeruginosa isolates from the SCUT were divided into exoU(+) or exoU(-). The exoU(+) strains contained the gene encoding ExoU, a powerful phospholipase toxin delivered into host cells by the type three secretion system. Isolates were then assessed for susceptibility to fluoroquinolone, cephalosporin, and aminoglycoside antibiotics using disk diffusion assays. Etest was used to determine the MIC of moxifloxacin and other fluoroquinolones. Laboratory isolates in which the exoU gene was added or deleted were also tested. A significantly higher proportion of exoU(+) strains were resistant to ciprofloxacin (p = 0.001), gatifloxacin (p = 0.003), and ofloxacin (p = 0.002) compared to exoU(-) isolates. There was no significant difference between exoU(+) or exoU(-) negative isolates with respect to susceptibility to other antibiotics except gentamicin. Infections involving resistant exoU(+) strains trended towards worse clinical outcome. Deletion or acquisition of exoU in laboratory isolates did not affect fluoroquinolone susceptibility. Fluoroquinolone susceptibility of P. aeruginosa isolated from the SCUT is consistent with previous studies showing elevated resistance involving exoU encoding (cytotoxic) strains, and suggest worse clinical outcome from infections involving resistant isolates. Determination of exoU expression in clinical isolates of P. aeruginosa may be helpful in directing clinical management of patients with microbial keratitis.

  15. Case Report: Clinically amyopathic dermatomyositis presenting acutely with isolated facial edema [version 2; referees: 2 approved

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    Efthymia Pappa

    2018-03-01

    Full Text Available A 45-year-old Asian man presented with acute-onset periorbital and facial edema associated with pyrexia. Muscle weakness was absent. Initial laboratory investigations showed an inflammatory reaction, while screening for infections was negative. Serum muscle enzyme levels were normal. He was hospitalized and treated empirically with antibiotics and corticosteroids, pending the result of facial skin and muscle biopsy. He showed a good clinical and laboratory response but an attempt to discontinue corticosteroids led to a prompt relapse of facial edema and pyrexia, associated with rising laboratory indices of inflammation. Biopsy findings were typical of dermatomyositis. Reintroduction of corticosteroid treatment resulted in complete clinical and laboratory remission. Facial edema as the sole clinical manifestation of dermatomyositis is extremely rare. There have been no previous reports of isolated facial edema in the setting of acute, clinically amyopathic dermatomyositis in adults. A high level of suspicion is required to make the diagnosis in the absence of myopathy and the hallmark cutaneous manifestations of the disease (heliotrope rash, Gottron papules.

  16. Defining a large set of full-length clones from a Xenopus tropicalis EST project.

    Science.gov (United States)

    Gilchrist, Michael J; Zorn, Aaron M; Voigt, Jana; Smith, James C; Papalopulu, Nancy; Amaya, Enrique

    2004-07-15

    Amphibian embryos from the genus Xenopus are among the best species for understanding early vertebrate development and for studying basic cell biological processes. Xenopus, and in particular the diploid Xenopus tropicalis, is also ideal for functional genomics. Understanding the behavior of genes in this accessible model system will have a significant and beneficial impact on the understanding of similar genes in other vertebrate systems. Here we describe the analysis of 219,270 X. tropicalis expressed sequence tags (ESTs) from four early developmental stages. From these, we have deduced a set of unique expressed sequences comprising approximately 20,000 clusters and 16,000 singletons. Furthermore, we developed a computational method to identify clones that contain the complete coding sequence and describe the creation for the first time of a set of approximately 7000 such clones, the full-length (FL) clone set. The entire EST set is cloned in a eukaryotic expression vector and is flanked by bacteriophage promoters for in vitro transcription, allowing functional experiments to be carried out without further subcloning. We have created a publicly available database containing the FL clone set and related clustering data (http://www.gurdon.cam.ac.uk/informatics/Xenopus.html) and we make the FL clone set publicly available as a resource to accelerate the process of gene discovery and function in this model organism. The creation of the unique set of expressed sequences and the FL clone set pave the way toward a large-scale systematic analysis of gene sequence, gene expression, and gene function in this vertebrate species.

  17. Microbial Protein Production from Candida tropicalis ATCC13803 in a Submerged Batch Fermentation Process

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    Sahar Golaghaiee

    2017-01-01

    Full Text Available Background and Objective: Microbial protein production can resolve one of the major world challenges, i.e. lack of protein sources. Candida tropicalis growth was investigated to specify a medium to reach the highest cell proliferation and protein production.Material and Methods: Fractional factorial design and the index of signal to noise ratio were applied for optimization of microbial protein production. Optimization process was conducted based on the experimental results of Taguchi approach designs. Fermentationwas performed at 25oC and the agitation speed of 300 rpm for 70 h. Ammonium sulfate, iron sulfate, glycine and glucose concentrations were considered as process variables. Optimization of the culture medium composition was conducted in order to obtain the highest cell biomass concentration and protein content. Experiment design was performed based on the Taguchi approach and L-16 orthogonal arrays using Qualitek-4 software.Results and Conclusion: Maximum biomass of 8.72 log (CFU ml-1 was obtained using the optimized medium with 0.3, 0.15, 2 and 80 g l-1 of ammonium sulfate, iron sulfate, glycine and glucose, respectively. Iron sulfate and ammonium sulfate with 41.76% (w w-1 and 35.27% (w w-1 contributions, respectively, were recognized as the main components for cell growth. Glucose and glycine with 17.12% and 5.86% (w w-1 contributions,respectively, also affected cell production. The highest interaction severity index of +54.16% was observed between glycine and glucose while the least one of +0.43% was recorded for ammonium sulfate and glycine. A deviation of 7% between the highestpredicted cell numbers and the experimented count confirms the suitability of the applied statistical method. High protein content of 52.16% (w w-1 as well as low fat and nucleic acids content suggest that Candida tropicalis is a suitable case for commercial processes.Conflict of interest: The authors declare that there is no conflict of interest.

  18. Can carotenoids mediate the potentially harmful effects of ultraviolet light in Silurana (Xenopus) tropicalis larvae?

    Science.gov (United States)

    Ogilvy, V; Preziosi, R F

    2012-08-01

    Amphibians have recently experienced unprecedented declines in the wild, the causes of which are often difficult to mitigate. This has increased the importance of ex situ conservation; however, long-term maintenance and breeding of amphibians in captivity often has limited success. In vertebrates, vitamin D is required for calcium homeostasis and is produced endogenously in skin exposed to ultraviolet (UV) light; however, UV light can be harmful to amphibians in some instances. Carotenoids are dietary pigments that may provide protection from UV light. The aim of this study was to assess the protective capability of carotenoids against the potentially harmful effects of UV light in Silurana (=Xenopus) tropicalis larvae raised in an enhanced or limited UV environment. Tadpole survival and the size and developmental stage reached by the end of the study period were measured. Carotenoids had a significantly positive effect on developmental rate in both UV-limited and UV-enhanced environments. Larvae in an enhanced UV environment were significantly larger than those raised under a limited UV environment, irrespective of diet. Carotenoid-fed larvae tended to have increased survival in relation to those raised without carotenoids, but only in a limited UV environment. Carotenoids appear to provide little protection against UV light in this case. The role of carotenoids in amphibian health has not previously been studied. We show that carotenoid availability significantly influences development and may increase survival in S. (X.) tropicalis larvae. This finding may have important implications for recommendations made on the nutrition of amphibians in captivity. © 2011 Blackwell Verlag GmbH.

  19. Metabolic responses in Candida tropicalis to complex inhibitors during xylitol bioconversion.

    Science.gov (United States)

    Wang, Shizeng; Li, Hao; Fan, Xiaoguang; Zhang, Jingkun; Tang, Pingwah; Yuan, Qipeng

    2015-09-01

    During xylitol fermentation, Candida tropicalis is often inhibited by inhibitors in hemicellulose hydrolysate. The mechanisms involved in the metabolic responses to inhibitor stress and the resistances to inhibitors are still not clear. To understand the inhibition mechanisms and the metabolic responses to inhibitors, a GC/MS-based metabolomics approach was performed on C. tropicalis treated with and without complex inhibitors (CI, including furfural, phenol and acetic acid). Partial least squares discriminant analysis was used to determine the metabolic variability between CI-treated groups and control groups, and 25 metabolites were identified as possible entities responsible for the discrimination caused by inhibitors. We found that xylose uptake rate and xylitol oxidation rate were promoted by CI treatment. Metabolomics analysis showed that the flux from xylulose to pentose phosphate pathway increased, and tricarboxylic acid cycle was disturbed by CI. Moreover, the changes in levels of 1,3-propanediol, trehalose, saturated fatty acids a