Evaluation of trimethoprim-sulfamethoxazole based combination therapy against Stenotrophomonas maltophilia: in vitro effects and clinical efficacy in cancer patients.

PubMed

Araoka, Hideki; Baba, Masaru; Okada, Chikako; Abe, Masahiro; Kimura, Muneyoshi; Yoneyama, Akiko

2017-05-01

The aim of this study was to evaluate the in vitro effects and clinical efficacies of trimethoprim-sulfamethoxazole (SXT) combined with other antimicrobial agents against Stenotrophomonas maltophilia. In vitro analysis was conducted on 89 S. maltophilia strains isolated from blood and the respiratory tract between June 2012 and October 2014. Levofloxacin (LVX), ticarcillin-clavulanic acid (TIM), and minocycline (MIN) were selected for an examination of their effects when individually combined with SXT by the checkerboard method. In addition, 29 S. maltophilia bacteremia cases were reviewed and the clinical efficacies of SXT-based combination therapies were analyzed. SXT+LVX showed synergy in 21, no interactions in 61, and antagonism in 7. SXT+TIM showed synergy in 71, and no interactions in 18. SXT+MIN showed synergy in 10, and no interactions in 79. The review of clinical data indicated that a combination of SXT+fluoroquinolone was not associated with improved prognosis compared with monotherapy. The in vitro data indicated that SXT+TIM had beneficial microbiological effects and was not antagonistic. Our in vitro and clinical data analyses do not support the routine use of SXT+fluoroquinolone combination therapy for S. maltophilia infection. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Susceptibility profiles of amphotericin B and posaconazole against clinically relevant mucorales species under hypoxic conditions.

PubMed

Maurer, Elisabeth; Binder, Ulrike; Sparber, Manuela; Lackner, Michaela; Caramalho, Rita; Lass-Flörl, Cornelia

2015-02-01

The effect of hypoxic conditions on the in vitro efficacy of amphotericin B and posaconazole against Mucorales was evaluated by defining MICs with Etest and broth microdilution and identifying minimal fungicidal concentrations (MFCs). With Etest, oxygen-dependent changes were detected, while the MIC and the MFC determined with broth microdilution remained unaltered with reduced oxygen levels. The observed differences depended on the method used. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

In vitro inhibition of bacterial growth by iron chelators.

PubMed

Qiu, Di-Hong; Huang, Zhu-Liang; Zhou, Tao; Shen, Chen; Hider, Robert C

2011-01-01

The antimicrobial activity of the iron(III)-selective 3-hydroxypyridin-4-one chelators, CP251(1) and CP252(2), was evaluated in comparison with that of diethylenetriamine-penta acetic acid (3). CP251 was found to exhibit an inhibitory effect on the growth of both Gram-positive and Gram-negative bacteria. CP251 may find application in the treatment of external infections such as those associated with wounds. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Susceptibility Testing of Medically Important Parasites.

PubMed

Genetu Bayih, Abebe; Debnath, Anjan; Mitre, Edward; Huston, Christopher D; Laleu, Benoît; Leroy, Didier; Blasco, Benjamin; Campo, Brice; Wells, Timothy N C; Willis, Paul A; Sjö, Peter; Van Voorhis, Wesley C; Pillai, Dylan R

2017-07-01

In the last 2 decades, renewed attention to neglected tropical diseases (NTDs) has spurred the development of antiparasitic agents, especially in light of emerging drug resistance. The need for new drugs has required in vitro screening methods using parasite culture. Furthermore, clinical laboratories sought to correlate in vitro susceptibility methods with treatment outcomes, most notably with malaria. Parasites with their various life cycles present greater complexity than bacteria, for which standardized susceptibility methods exist. This review catalogs the state-of-the-art methodologies used to evaluate the effects of drugs on key human parasites from the point of view of drug discovery as well as the need for laboratory methods that correlate with clinical outcomes. Copyright © 2017 American Society for Microbiology.

Structure of the Anthrax Research Literature

DTIC Science & Technology

2006-01-01

4; identification 4; staphylococcus - aureus 3; pharmacology & pharmacy 3; microbiology 3; pharmacology & pharmacy 2; biotechnology & applied...proteins 4; microbiology 4; escherichia-coli 4; bacillus-anthracis 4; cell-wall 3; staphylococcus - aureus 3 Country usa 9; france 7; england 2...pathogen detection using a microchip PCR array Instrument 199 In vitro selection of DNA aptamers to anthrax spores with electrochemiluminescence

[Microbiological findings in patients with recurrent vulvovaginal candidiasis in the Hradec Králové Faculty Hospital 1995-2002].

PubMed

Buchta, V; Spacek, J

2004-01-01

To evaluate the microbiological findings in the patients with the recurrent vulvovaginal candidiasis (RVVC) with a focus on the establishment of fungal etiology and its in vitro antifungal susceptibility. Retrospective clinical and laboratory study. Department of Obstetrics and Gynecology, Medical Faculty Hradec Králové, Charles University, Prague, Department of Clinical Microbiology, Medical Faculty Hradec Králové, Charles University, Prague, Department of Biological and Medical Sciences, Faculty of Pharmacy Hradec Králové, Charles University, Prague. An analysis of clinical and anamnestic data in outpatients of the Dept. of Obstetrics and Gynecology and the laboratory data from the microbiological examinations performed in the Dept. of Clinical Microbiology from 1995 to 2002. Candida albicans accounted for 88.5% of the episodes of RVVC in the setting of 56 patients. Non-albicans Candida species were represented especially by C. glabrata (4.9%) and C. krusei (3.1%). There were no considerable differences between the spectrum of RVVC and acute vulvovaginal candidiasis with the exception of Saccharomyces cerevisiae (0.7% in RVVC vs. 3.7% in acute VVC). Mycological findings in 61 (20.5%) samples were accompanied by bacterial microbiota with the predominance of Streptococcus agalactiae (n = 15) and Gardnerella vaginalis (n = 9). Decreased antifungal susceptibility determined by the disk test was observed in the strains of C. glabrata, C. krusei and S. cerevisiae, the other yeast isolates being susceptible to all ten antifungal drugs tested. The microbiological examination was decisive for the establishment of the diagnosis of RVVC in most cases. The most frequent etiological agents responsible for the attacks of RVVC as well as for acute vulvovaginal candidiasis was C. albicans, which was generally susceptible to antifungal drugs.

Antibacterial activity of LauriPure in vitro and on skin of processed broilers.

USDA-ARS?s Scientific Manuscript database

Studies were conducted to examine the ability of LauriPure to inhibit the growth of Salmonella Typhimurium, Escherichia coli, Staphylococcus simulans, and Listeria innocua isolates recovered from processed broiler carcasses. In vitro studies were conducted using the Bioscreen C Microbiology Reader t...

In vitro and in vivo anti-microbial activity evaluation of inactivated cells of Lactobacillus salivarius CECT 5713 against Streptococcus mutans.

PubMed

Sañudo, Ana I; Luque, Roberto; Díaz-Ropero, Mª Paz; Fonollá, Juristo; Bañuelos, Óscar

2017-12-01

Defining the etiology of dental caries is a complex problem. The microbiological approach has included Streptococcus mutans as one of the bacterial species involved in this disease. This research investigates the inhibitory effects of heat-inactivated Lactobacillus salivarius CECT 5713 against S. mutans using in vitro and in vivo assays. On the one hand, the effect of non-viable L. salivarius CECT 5713 on the in vitro adhesion of S. mutans to hydroxyapatite discs was evaluated. On the other hand, levels of Streptococcus mutans, amount of salivary flow and salivary pH before and after taking the rinse with the non-viable L. salivarius CECT 5713 in healthy volunteers were assessed (self-controlled open-label pilot study). The levels of S. mutans seemed to decrease in the in vitro and in vivo assays (p<0.05). The in vitro effect of non-viable L. salivarius was maintained until 36 months of storage. In addition, the reduction of S. mutans salivary concentration in the volunteers was statistically significant from the third day until two weeks of treatment. Heat-inactivated L. salivarius CECT 5713 prevents S. mutans adhesion to hydroxyapatite and could be used as a strategy to reduce the salivary concentration of this oral pathogen. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative In Vitro Efficacy of Doripenem and Imipenem Against Multi-Drug Resistant Pseudomonas aeruginosa.

PubMed

Wali, Nadia; Mirza, Irfan Ali

2016-04-01

To compare the in vitro efficacy of doripenem and imipenem against multi-drug resistant (MDR) Pseudomonas aeruginosa from various clinical specimens. Descriptive cross-sectional study. Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from November 2012 to November 2013. MDR Pseudomonas aeruginosa isolates from various clinical samples were included in the study. Susceptibility of Pseudomonas aeruginosa against doripenem and imipenem was performed by E-test strip and agar dilution methods. The results were interpreted as recommended by Clinical Laboratory Standard Institute (CLSI) guidelines. The maximum number of Pseudomonas aeruginosa were isolated from pure pus and pus swabs. In vitro efficacy of doripenem was found to be more effective as compared to imipenem against MDR Pseudomonas aeruginosa with both E-test strip and agar dilution methods. Overall, p-values of 0.014 and 0.037 were observed when susceptibility patterns of doripenem and imipenem were evaluated with E-test strip and agar dilution methods. In vitro efficacy of doripenem was found to be better against MDR Pseudomonas aeruginosaas compared to imipenem when tested by both E-test and agar dilution methods.

The Enzyme Function Initiative†

PubMed Central

Gerlt, John A.; Allen, Karen N.; Almo, Steven C.; Armstrong, Richard N.; Babbitt, Patricia C.; Cronan, John E.; Dunaway-Mariano, Debra; Imker, Heidi J.; Jacobson, Matthew P.; Minor, Wladek; Poulter, C. Dale; Raushel, Frank M.; Sali, Andrej; Shoichet, Brian K.; Sweedler, Jonathan V.

2011-01-01

The Enzyme Function Initiative (EFI) was recently established to address the challenge of assigning reliable functions to enzymes discovered in bacterial genome projects; in this Current Topic we review the structure and operations of the EFI. The EFI includes the Superfamily/Genome, Protein, Structure, Computation, and Data/Dissemination Cores that provide the infrastructure for reliably predicting the in vitro functions of unknown enzymes. The initial targets for functional assignment are selected from five functionally diverse superfamilies (amidohydrolase, enolase, glutathione transferase, haloalkanoic acid dehalogenase, and isoprenoid synthase), with five superfamily-specific Bridging Projects experimentally testing the predicted in vitro enzymatic activities. The EFI also includes the Microbiology Core that evaluates the in vivo context of in vitro enzymatic functions and confirms the functional predictions of the EFI. The deliverables of the EFI to the scientific community include: 1) development of a large-scale, multidisciplinary sequence/structure-based strategy for functional assignment of unknown enzymes discovered in genome projects (target selection, protein production, structure determination, computation, experimental enzymology, microbiology, and structure-based annotation); 2) dissemination of the strategy to the community via publications, collaborations, workshops, and symposia; 3) computational and bioinformatic tools for using the strategy; 4) provision of experimental protocols and/or reagents for enzyme production and characterization; and 5) dissemination of data via the EFI’s website, enzymefunction.org. The realization of multidisciplinary strategies for functional assignment will begin to define the full metabolic diversity that exists in nature and will impact basic biochemical and evolutionary understanding, as well as a wide range of applications of central importance to industrial, medicinal and pharmaceutical efforts. PMID:21999478

The Enzyme Function Initiative.

PubMed

Gerlt, John A; Allen, Karen N; Almo, Steven C; Armstrong, Richard N; Babbitt, Patricia C; Cronan, John E; Dunaway-Mariano, Debra; Imker, Heidi J; Jacobson, Matthew P; Minor, Wladek; Poulter, C Dale; Raushel, Frank M; Sali, Andrej; Shoichet, Brian K; Sweedler, Jonathan V

2011-11-22

The Enzyme Function Initiative (EFI) was recently established to address the challenge of assigning reliable functions to enzymes discovered in bacterial genome projects; in this Current Topic, we review the structure and operations of the EFI. The EFI includes the Superfamily/Genome, Protein, Structure, Computation, and Data/Dissemination Cores that provide the infrastructure for reliably predicting the in vitro functions of unknown enzymes. The initial targets for functional assignment are selected from five functionally diverse superfamilies (amidohydrolase, enolase, glutathione transferase, haloalkanoic acid dehalogenase, and isoprenoid synthase), with five superfamily specific Bridging Projects experimentally testing the predicted in vitro enzymatic activities. The EFI also includes the Microbiology Core that evaluates the in vivo context of in vitro enzymatic functions and confirms the functional predictions of the EFI. The deliverables of the EFI to the scientific community include (1) development of a large-scale, multidisciplinary sequence/structure-based strategy for functional assignment of unknown enzymes discovered in genome projects (target selection, protein production, structure determination, computation, experimental enzymology, microbiology, and structure-based annotation), (2) dissemination of the strategy to the community via publications, collaborations, workshops, and symposia, (3) computational and bioinformatic tools for using the strategy, (4) provision of experimental protocols and/or reagents for enzyme production and characterization, and (5) dissemination of data via the EFI's Website, http://enzymefunction.org. The realization of multidisciplinary strategies for functional assignment will begin to define the full metabolic diversity that exists in nature and will impact basic biochemical and evolutionary understanding, as well as a wide range of applications of central importance to industrial, medicinal, and pharmaceutical efforts. © 2011 American Chemical Society

Galactomannan enzyme immunoassay and quantitative Real Time PCR as tools to evaluate the exposure and response in a rat model of aspergillosis after posaconazole prophylaxis.

PubMed

Cendejas-Bueno, Emilio; Forastiero, Agustina; Ruiz, Isabel; Mellado, Emilia; Buitrago, María José; Gavaldà, Joan; Gomez-Lopez, Alicia

2016-11-01

A steroid-immunosuppressed rat model of invasive pulmonary aspergillosis was use to examine the usefulness of galactomannan enzyme immunoassay (GM) and quantitative real time PCR (RT-PCR) in evaluating the association between response and exposure after a high dose of prophylactic posaconazole. Two different strains of Aspergillus fumigatus with different in vitro posaconazole susceptibility were used. Serum concentrations demonstrated similar posaconazole exposure for all treated animals. However, response to posaconazole relied on the in vitro susceptibility of the infecting strain. After prophylaxis, galactomannan index and fungal burden only decreased in those animals infected with the most susceptible strain. This study demonstrated that both biomarkers may be useful tools for predicting efficacy of antifungal compounds in prophylaxis. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Advances Afoot in Microbiology.

PubMed

Patel, Robin; Karon, Brad S

2017-07-01

In 2016, the American Academy of Microbiology convened a colloquium to examine point-of-care (POC) microbiology testing and to evaluate its effects on clinical microbiology. Colloquium participants included representatives from clinical microbiology laboratories, industry, and the government, who together made recommendations regarding the implementation, oversight, and evaluation of POC microbiology testing. The colloquium report is timely and well written (V. Dolen et al., Changing Diagnostic Paradigms for Microbiology , 2017, https://www.asm.org/index.php/colloquium-reports/item/6421-changing-diagnostic-paradigms-for-microbiology?utm_source=Commentary&utm_medium=referral&utm_campaign=diagnostics). Emerging POC microbiology tests, especially nucleic acid amplification tests, have the potential to advance medical care. Copyright © 2017 American Society for Microbiology.

Advances Afoot in Microbiology

PubMed Central

Karon, Brad S.

2017-01-01

ABSTRACT In 2016, the American Academy of Microbiology convened a colloquium to examine point-of-care (POC) microbiology testing and to evaluate its effects on clinical microbiology. Colloquium participants included representatives from clinical microbiology laboratories, industry, and the government, who together made recommendations regarding the implementation, oversight, and evaluation of POC microbiology testing. The colloquium report is timely and well written (V. Dolen et al., Changing Diagnostic Paradigms for Microbiology, 2017, https://www.asm.org/index.php/colloquium-reports/item/6421-changing-diagnostic-paradigms-for-microbiology?utm_source=Commentary&utm_medium=referral&utm_campaign=diagnostics). Emerging POC microbiology tests, especially nucleic acid amplification tests, have the potential to advance medical care. PMID:28539341

Doxycycline-containing glass ionomer cement for arresting residual caries: an in vitro study and a pilot trial.

PubMed

Castilho, Aline Rogéria Freire de; Duque, Cristiane; Kreling, Paula Fernanda; Pereira, Jesse Augusto; Paula, Andreia Bolzan de; Sinhoreti, Mario Alexandre Coelho; Puppin-Rontani, Regina Maria

2018-01-01

In a previous study, we demonstrated that the incorporation of doxycycline hyclate (DOX) into resin-modified glass ionomer cement (RMGIC) inhibited important cariogenic microorganisms, without modifying its biological and mechanical characteristics. In this study, we keep focused on the effect of that experimental material as a potential therapy for arresting residual caries by analyzing other in vitro properties and conducting a pilot clinical trial assessing the in vivo effect of DOX-containing RMGIC on residual mutans streptococci after partial carious removal in primary molars. Specimens of the groups RMGIC (control); RMGIC + 1.5% DOX; RMGIC + 3% DOX; and RMGIC + 4.5% DOX were made to evaluate the effect of DOX incorporation on surface microhardness and fluoride release of RMGIC and against biofilm of Streptococcus mutans. Clinical intervention consisted of partial caries removal comparing RMGIC and RMGIC + 4.5% DOX as lining materials. After 3 months, clinical and microbiologic evaluations were performed. Data were submitted to ANOVA/Tukey or Wilcoxon/Mann-Whitney set as α=0.05. Fluoride release and surface microhardness was not influenced by the incorporation of DOX (p>0.05). There was a significant reduction of S. mutans biofilm over the material surface with the increase of DOX concentration. After clinical trial, the remaining dentin was hard and dry. Additionally, mutans streptococci were completely eliminated after 3 months of treatment with RMGIC + 4.5% DOX. The incorporation of DOX provided better antibiofilm effect, without jeopardizing fluoride release and surface microhardness of RMGIC. This combination also improved the in vivo shortterm microbiological effect of RMGIC after partial caries removal.

In Vivo Caprine Model for Osteomyelitis and Evaluation of Biofilm-Resistant Intramedullary Nails

PubMed Central

Tran, Nhiem; Tran, Phong A.; Jarrell, John D.; Engiles, Julie B.; Thomas, Nathan P.; Young, Matthew D.; Hayda, Roman A.; Born, Christopher T.

2013-01-01

Bone infection remains a formidable challenge to the medical field. The goal of the current study is to evaluate antibacterial coatings in vitro and to develop a large animal model to assess coated bone implants. A novel coating consisting of titanium oxide and siloxane polymer doped with silver was created by metal-organic methods. The coating was tested in vitro using rapid screening techniques to determine compositions which inhibited Staphylococcus aureus growth, while not affecting osteoblast viability. The coating was then applied to intramedullary nails and evaluated in vivo in a caprine model. In this pilot study, a fracture was created in the tibia of the goat, and Staphylococcus aureus was inoculated directly into the bone canal. The fractures were fixed by either coated (treated) or non-coated intramedullary nails (control) for 5 weeks. Clinical observations as well as microbiology, mechanical, radiology, and histology testing were used to compare the animals. The treated goat was able to walk using all four limbs after 5 weeks, while the control was unwilling to bear weight on the fixed leg. These results suggest the antimicrobial potential of the hybrid coating and the feasibility of the goat model for antimicrobial coated intramedullary implant evaluation. PMID:23841085

A quantitative method to evaluate the donor corneal tissue quality used in a comparative study between two hypothermic preservation media.

PubMed

Parekh, Mohit; Salvalaio, Gianni; Ferrari, Stefano; Amoureux, Marie-Claude; Albrecht, Cecile; Fortier, Denis; Ponzin, Diego

2014-12-01

To standardize a new evaluation technique for calculating the overall quality (OQ) of the donor cornea and validate it using a comparative study of corneas preserved in Optisol-GS and Cornea Cold®. Thirty pairs of donor corneas were selected for a 4 week in vitro comparative study using masked observers. Physiological parameters like thickness, transparency, viable endothelial cell density (VECD) and morphology were transformed to numerical range (0-4) to obtain the OQ. Microbiological examination was performed using Bactec instrument. Students t test showed statistically better results (p < 0.05) from week 3 for thickness, week 2 for transparency and week 1 for morphology and VECD; statistical significance (p < 0.05) was found for OQ from week 2 for the corneas preserved in Cornea Cold® compared to Optisol-GS. Epithelial quality was similar regardless of the medium. Microbiological examination showed absence of aerobic and anaerobic microorganisms in both media. OQ method is efficient, consistent and easy, now validated for comparative studies. Further refinement is necessary for its use at eye-banks, bio-banks and research or transplantation purposes. Cornea Cold® is a promising hypothermic corneal storage medium with preservation time ≤21 days. This permits higher flexibility, evaluation accuracy, longer duration for surgical preparation and ease of transportation.

Two-Drug Antimicrobial Chemotherapy: A Mathematical Model and Experiments with Mycobacterium marinum

PubMed Central

Ankomah, Peter; Levin, Bruce R.

2012-01-01

Multi-drug therapy is the standard-of-care treatment for tuberculosis. Despite this, virtually all studies of the pharmacodynamics (PD) of mycobacterial drugs employed for the design of treatment protocols are restricted to single agents. In this report, mathematical models and in vitro experiments with Mycobacterium marinum and five antimycobacterial drugs are used to quantitatively evaluate the pharmaco-, population and evolutionary dynamics of two-drug antimicrobial chemotherapy regimes. Time kill experiments with single and pairs of antibiotics are used to estimate the parameters and evaluate the fit of Hill-function-based PD models. While Hill functions provide excellent fits for the PD of each single antibiotic studied, rifampin, amikacin, clarithromycin, streptomycin and moxifloxacin, two-drug Hill functions with a unique interaction parameter cannot account for the PD of any of the 10 pairs of these drugs. If we assume two antibiotic-concentration dependent functions for the interaction parameter, one for sub-MIC and one for supra-MIC drug concentrations, the modified biphasic Hill function provides a reasonably good fit for the PD of all 10 pairs of antibiotics studied. Monte Carlo simulations of antibiotic treatment based on the experimentally-determined PD functions are used to evaluate the potential microbiological efficacy (rate of clearance) and evolutionary consequences (likelihood of generating multi-drug resistance) of these different drug combinations as well as their sensitivity to different forms of non-adherence to therapy. These two-drug treatment simulations predict varying outcomes for the different pairs of antibiotics with respect to the aforementioned measures of efficacy. In summary, Hill functions with biphasic drug-drug interaction terms provide accurate analogs for the PD of pairs of antibiotics and M. marinum. The models, experimental protocols and computer simulations used in this study can be applied to evaluate the potential microbiological and evolutionary efficacy of two-drug therapy for any bactericidal antibiotics and bacteria that can be cultured in vitro. PMID:22253599

Structural characterization of 1,8-naphthalimides and in vitro microbiological activity of their Cu(II) and Zn(II) complexes

NASA Astrophysics Data System (ADS)

Grabchev, Ivo; Yordanova, Stanislava; Bosch, Paula; Vasileva-Tonkova, Evgenia; Kukeva, Rositsa; Stoyanov, Stanimir; Stoyanova, Radostina

2017-02-01

Two new 1,8-naphthalimide derivatives (NI1 and NI2) have been synthesized and characterized. The photophysical properties of the new compounds have been investigated in organic solvents of different polarity. It has been shown that both compounds are solvent depended. Cu(II) and Zn(II) complexes of NI2 were obtained and characterized by IR-NMR, fluorescence and EPR spectroscopy. The influence of different metal cations on the fluorescence intensity has been investigated in acetonitrile solution. Antimicrobial composite PLA-metal complexes materials have been obtained for the first time. Microbiological activity of both metal complexes has been investigated in vitro against different Gram-positive and Gram-negative bacteria and two yeasts. The various antimicrobial activities and the minimum inhibitory concentrations (MICs) of both complexes have been determined. The microbiological activity of composite materials PLA-metal complexes in thin polymeric film has also been investigated. The results suggest that the new metal complexes could find application in designing new antimicrobial preparations to control the spread of infections.

Doxycycline hydrochloride-metronidazole solid lipid microparticles gels for treatment of periodontitis: development, in-vitro and in-vivo clinical evaluation.

PubMed

Gad, Heba A; Kamel, Amany O; Ezzat, Ola M; El Dessouky, Hadir F; Sammour, Omaima A

2017-11-01

To formulate solid lipid microparticles (SLMs) encapsulating doxycycline hydrochloride (DH) and metronidazole (MT) for the treatment of periodontal diseases. SLMs were prepared applying hot homogenization method, using different types of lipids and stabilized with various types and concentrations of surfactants. The optimized formula was subjected to freeze-drying followed by incorporation into poloxamer gel. Microbiological and clinical evaluation of the selected SLMs on patients suffering from periodontal diseases was performed. SLMs could entrap high percentage of both drugs (81.14% and 68.75 % for doxycycline hydrochloride and metronidazole respectively). Transmission electron microscopy images of SLMs showed nearly spherical particles. Freeze-dried SLMs showed satisfactory stability for three months. Combined drugs were molecularly dispersed in SLMs. Incorporation of the freeze-dried SLMs powder in poloxamer gel could control the drugs release for 72 h. In-vivo study revealed effective and safe use of SLMs gel for periodontitis treatment. Significant improvement in both microbiological and clinical parameters was observed as compared to scaling and root planing alone. The formulated SLMs gel offers an applicable dosage form that can be injected directly into the periodontal pocket as adjunctive to scaling and root planing.

[Effects of inhibitory activity on mycelial growth of Candida albicans and therapy for murine oral candidiasis by the combined use of terpinen-4-ol and a middle-chain fatty acid, capric acid].

PubMed

Ninomiya, Kentaro; Hayama, Kazumi; Ishijima, Sanae; Takahashi, Miki; Kurihara, Junichi; Abe, Shigeru

2013-01-01

The combined effect of terpinen-4-ol, the main component of tea tree oil, and capric acid against mycelial growth of Candida albicans and murine oral candidiasis was evaluated in vitro and in vivo. Mycelial growth of C. albicans was estimated by the Cristal violet method. Combination of these compounds revealed a potent synergistic inhibition of growth. Therapeutic efficacy of the combination was evaluated microbiologically in murine oral candidiasis, and its application of the compounds clearly demonstrated therapeutic activity. Based on these results, the combined agent of terpinen-4-ol and capric acid was discussed as a possible candidate for oral candidiasis therapy.

Doxycycline-containing glass ionomer cement for arresting residual caries: an in vitro study and a pilot trial

PubMed Central

Duque, Cristiane; Kreling, Paula Fernanda; Pereira, Jesse Augusto; de Paula, Andreia Bolzan; Sinhoreti, Mario Alexandre Coelho; Puppin-Rontani, Regina Maria

2018-01-01

Abstract In a previous study, we demonstrated that the incorporation of doxycycline hyclate (DOX) into resin-modified glass ionomer cement (RMGIC) inhibited important cariogenic microorganisms, without modifying its biological and mechanical characteristics. In this study, we keep focused on the effect of that experimental material as a potential therapy for arresting residual caries by analyzing other in vitro properties and conducting a pilot clinical trial assessing the in vivo effect of DOX-containing RMGIC on residual mutans streptococci after partial carious removal in primary molars. Specimens of the groups RMGIC (control); RMGIC + 1.5% DOX; RMGIC + 3% DOX; and RMGIC + 4.5% DOX were made to evaluate the effect of DOX incorporation on surface microhardness and fluoride release of RMGIC and against biofilm of Streptococcus mutans. Clinical intervention consisted of partial caries removal comparing RMGIC and RMGIC + 4.5% DOX as lining materials. After 3 months, clinical and microbiologic evaluations were performed. Data were submitted to ANOVA/Tukey or Wilcoxon/Mann-Whitney set as α=0.05. Fluoride release and surface microhardness was not influenced by the incorporation of DOX (p>0.05). There was a significant reduction of S. mutans biofilm over the material surface with the increase of DOX concentration. After clinical trial, the remaining dentin was hard and dry. Additionally, mutans streptococci were completely eliminated after 3 months of treatment with RMGIC + 4.5% DOX. The incorporation of DOX provided better antibiofilm effect, without jeopardizing fluoride release and surface microhardness of RMGIC. This combination also improved the in vivo shortterm microbiological effect of RMGIC after partial caries removal. PMID:29742263

Antimicrobial effect of chlorhexidine digluconate in dentin: In vitro and in situ study.

PubMed

Borges, Fátima Maria Cavalcante; de Melo, Mary Anne Sampaio; Lima, Juliana Paiva Marques; Zanin, Iriana Carla Junqueria; Rodrigues, Lidiany Karla Azevedo

2012-01-01

The aim of this study was to evaluate a very short-term in vitro and in situ effect of 2% chlorhexidine-digluconate-based (CHX) cavity cleanser on the disinfection of dentin demineralized by cariogenic bacteria. Human dentin slabs were randomly allocated and used in 2 distinct phases, in vitro and in situ, for obtaining demineralized dentin. In vitro, the slabs (n=15) were immersed for 5 days in BHI broth inoculated with Streptococcus mutans CTT 3440. In situ, a double-blind design was conducted in one phase of 14 days, during which 20 volunteers wore palatal devices containing two human dental dentin slabs. On 5(th) day in vitro and 14(th) day in situ, the slabs were allocated to the two groups: Control group (5 μl of 0.9% NaCl solution) and CHX group (5 μl of 2% chlorhexidine digluconate solution, Cavity Cleanser™ BISCO, Schaumburg, IL, EUA), for 5 minutes. The microbiological analyses were performed immediately before and after the treatments. The log reductions means found for CHX treatment on tested micro organisms were higher when compared to Control group either in vitro or in situ conditions. Our results showed that CHX was effective in reducing the cultivable microbiota in contaminated dentin. Furthermore, although the use of chlorhexidine-digluconate-based cavity disinfectant did not completely eliminate the viable microorganisms, it served as a suitable agent to disinfect tooth preparations.

Evaluation of an online program to teach microbiology to internal medicine residents.

PubMed

Guarner, Jeannette; Burd, Eileen M; Kraft, Colleen S; Armstrong, Wendy S; Lenorr, Kenya; Spicer, Jennifer O; Martin, Donna; del Rio, Carlos

2015-01-01

Microbiology rounds are an integral part of infectious disease consultation service. During microbiology rounds, we highlight microbiology principles using vignettes. We created case-based, interactive, microbiology online modules similar to the vignettes presented during microbiology rounds. Since internal medicine residents rotating on our infectious disease elective have limited time to participate in rounds and learn microbiology, our objective was to evaluate the use of the microbiology online modules by internal medicine residents. We asked residents to complete 10 of 25 online modules during their infectious disease elective. We evaluated which modules they chose and the change in their knowledge level. Forty-six internal medicine residents completed assessments given before and after accessing the modules with an average of 11/20 (range, 6 to 19) and 16/20 (range, 9 to 20) correct questions, respectively (average improvement, 5 questions; P = 0.0001). The modules accessed by more than 30 residents included those related to Clostridium difficile, anaerobes, Candida spp., Streptococcus pneumoniae, influenza, Mycobacterium tuberculosis, and Neisseria meningitidis. We demonstrated improved microbiology knowledge after completion of the online modules. This improvement may not be solely attributed to completing the online modules, as fellows and faculty may have provided additional microbiology education during the rotation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Evaluation of an Online Program To Teach Microbiology to Internal Medicine Residents

PubMed Central

Burd, Eileen M.; Kraft, Colleen S.; Armstrong, Wendy S.; Lenorr, Kenya; Spicer, Jennifer O.; Martin, Donna; del Rio, Carlos

2014-01-01

Microbiology rounds are an integral part of infectious disease consultation service. During microbiology rounds, we highlight microbiology principles using vignettes. We created case-based, interactive, microbiology online modules similar to the vignettes presented during microbiology rounds. Since internal medicine residents rotating on our infectious disease elective have limited time to participate in rounds and learn microbiology, our objective was to evaluate the use of the microbiology online modules by internal medicine residents. We asked residents to complete 10 of 25 online modules during their infectious disease elective. We evaluated which modules they chose and the change in their knowledge level. Forty-six internal medicine residents completed assessments given before and after accessing the modules with an average of 11/20 (range, 6 to 19) and 16/20 (range, 9 to 20) correct questions, respectively (average improvement, 5 questions; P = 0.0001). The modules accessed by more than 30 residents included those related to Clostridium difficile, anaerobes, Candida spp., Streptococcus pneumoniae, influenza, Mycobacterium tuberculosis, and Neisseria meningitidis. We demonstrated improved microbiology knowledge after completion of the online modules. This improvement may not be solely attributed to completing the online modules, as fellows and faculty may have provided additional microbiology education during the rotation. PMID:25392364

Evolution of the Pseudomonas aeruginosa Aminoglycoside Mutational Resistome In Vitro and in the Cystic Fibrosis Setting.

PubMed

López-Causapé, Carla; Rubio, Rosa; Cabot, Gabriel; Oliver, Antonio

2018-04-01

Inhaled administration of high doses of aminoglycosides is a key maintenance treatment of Pseudomonas aeruginosa chronic respiratory infections in cystic fibrosis (CF). We analyzed the dynamics and mechanisms of stepwise high-level tobramycin resistance development in vitro and compared the results with those of isogenic pairs of susceptible and resistant clinical isolates. Resistance development correlated with fusA1 mutations in vitro and in vivo. pmrB mutations, conferring polymyxin resistance, were also frequently selected in vitro In contrast, mutational overexpression of MexXY, a hallmark of aminoglycoside resistance in CF, was not observed in in vitro evolution experiments. Copyright © 2018 American Society for Microbiology.

Development of an in vitro Assay, Based on the BioFilm Ring Test®, for Rapid Profiling of Biofilm-Growing Bacteria

PubMed Central

Di Domenico, Enea G.; Toma, Luigi; Provot, Christian; Ascenzioni, Fiorentina; Sperduti, Isabella; Prignano, Grazia; Gallo, Maria T.; Pimpinelli, Fulvia; Bordignon, Valentina; Bernardi, Thierry; Ensoli, Fabrizio

2016-01-01

Microbial biofilm represents a major virulence factor associated with chronic and recurrent infections. Pathogenic bacteria embedded in biofilms are highly resistant to environmental and chemical agents, including antibiotics and therefore difficult to eradicate. Thus, reliable tests to assess biofilm formation by bacterial strains as well as the impact of chemicals or antibiotics on biofilm formation represent desirable tools for a most effective therapeutic management and microbiological risk control. Current methods to evaluate biofilm formation are usually time-consuming, costly, and hardly applicable in the clinical setting. The aim of the present study was to develop and assess a simple and reliable in vitro procedure for the characterization of biofilm-producing bacterial strains for future clinical applications based on the BioFilm Ring Test® (BRT) technology. The procedure developed for clinical testing (cBRT) can provide an accurate and timely (5 h) measurement of biofilm formation for the most common pathogenic bacteria seen in clinical practice. The results gathered by the cBRT assay were in agreement with the traditional crystal violet (CV) staining test, according to the κ coefficient test (κ = 0.623). However, the cBRT assay showed higher levels of specificity (92.2%) and accuracy (88.1%) as compared to CV. The results indicate that this procedure offers an easy, rapid and robust assay to test microbial biofilm and a promising tool for clinical microbiology. PMID:27708625

Paediatric bacterial keratitis cases in Shanghai: microbiological profile, antibiotic susceptibility and visual outcomes

PubMed Central

Hong, J; Chen, J; Sun, X; Deng, S X; Chen, L; Gong, L; Cao, W; Yu, X; Xu, J

2012-01-01

Purpose The purpose of this study was to review the microbiological profile, in vitro antibiotic susceptibility and visual outcomes of paediatric microbial keratitis in Shanghai, China over the past 6 years. Methods Medical records of patients aged ≤16 years were reviewed, who were diagnosed as having bacterial keratitis between 1 January 2005 and 31 December 2010. Bacterial culture results and in vitro antibiotic susceptibility were analysed. A logistic regression analysis was conducted to evaluate the relationship between visual impairment and possible risk factors. Results Eighty consecutive cases of paediatric bacterial keratitis cases were included, among which 59 were identified as having positive culture. Staphylococcus epidermidis was the most commonly isolated organism (n=23; 39.0%), followed by Streptococcus pneumoniae (n=11; 18.6%) and Pseudomonas aeruginosa (n=6; 10.2%). Antibiotic sensitivities revealed that tested bacteria had low resistance rates to fluoroquinolones and aminoglycosides (8.3–18.4% and 12.5–24.4%, respectively). Multivariate logistic regression analysis proved that visual impairment was significantly associated with Gram-negative bacterial infection (odds ratio (OR)=7.626; P=0.043) and an increasing number of resistant antibiotics (OR=0.385; P=0.040). Conclusions S. epidermidis was the most common isolated organism in Shanghai paediatric keratitis. The fluoroquinolones and aminoglycosides remained good choices for treating these patients. Gram-negative bacterial infection and an increasing number of resistant antibiotics were associated with worse visual prognoses in paediatric keratitis. PMID:23079751

Decolorization of salt-alkaline effluent with industrial reactive dyes by laccase-producing Basidiomycetes strains.

PubMed

Moreira-Neto, S L; Mussatto, S I; Machado, K M G; Milagres, A M F

2013-04-01

The discharge of highly coloured synthetic dye effluents into rivers and lakes is harmful to the water bodies, and therefore, intensive researches have been focussed on the decolorization of wastewater by biological, physical or chemical treatments. In the present study, 12 basidiomycetes strains from the genus Pleurotus, Trametes, Lentinus, Peniophora, Pycnoporus, Rigidoporus, Hygrocybe and Psilocybe were evaluated for decolorization of the reactive dyes Cibacron Brilliant Blue H-GR and Cibacron Red FN-2BL, both in solid and liquid media. Among the evaluated fungi, seven showed great ability to decolorize the synthetic textile effluent, both in vivo (74-77%) or in vitro (60-74%), and laccase was the main ligninolytic enzyme involved on dyes decolorization. Pleurotus ostreatus, Trametes villosa and Peniophora cinerea reduced near to 60% of the effluent colour after only 1 h of treatment. The decolorization results were still improved by establishing the nitrogen source and amount to be used during the fungal strains cultivation in synthetic medium previous their action on the textile effluent, with yeast extract being a better nitrogen source than ammonium tartarate. These results contribute for the development of an effective microbiological process for decolorization of dye effluents with reduced time of treatment. © 2013 The Society for Applied Microbiology.

Exploring the antioxidant potentiality of two food by-products into a topical cream: stability, in vitro and in vivo evaluation.

PubMed

Rodrigues, F; Sarmento, B; Amaral, M Helena; Oliveira, M Beatriz P P

2016-01-01

Coffee silverskin (CS), a food by-product of the coffee roasting industry, has been studied as an active ingredient for skin care products due to its high potential of antioxidant activity and low cytotoxicity. Another food waste used as ingredient with promising characteristics is obtained from Medicago sativa (MS), which antioxidants and isoflavones content is high. The aim of this study is to evaluate and characterize a new body formulation containing two food by-products extracts. Different parameters (such as pH, rheological behavior, color, antioxidant content and microbiological analysis) of a body cream formulation containing by-products (CSMS) and a formulation without extracts (F) were evaluated under a stability study during 180 days at different temperatures. Moreover, the in vitro cell toxicity and the in vivo skin safety and protective effects were also assessed. Formulation showed stable physical properties and antioxidant activity during 180 days of storage. In vitro toxicity was screened in two skin cell lines (fibroblasts and keratinocytes) and any toxicity was reported. The in vivo test carried out showed that, with respect to irritant effects, CSMS formulation can be regarded as safe for topical application and the skin hydratation improved after 30 days of its use. Also, considering the consumer acceptance, more than 90% of volunteers classified it as very pleasant. CSMS formulation is stable and safe for topical use as no adverse and/or side effects were observed during the application period of testing, improving skin protective properties.

Evaluation of an antibody avidity index method for detecting recent human immunodeficiency virus type 1 infection using an automated chemiluminescence immunoassay.

PubMed

Fernández, Gema; Manzardo, Christian; Montoliu, Alexandra; Campbell, Colin; Fernández, Gregorio; Casabona, Jordi; Miró, José Maria; Matas, Lurdes; Rivaya, Belén; González, Victoria

2015-04-01

Recent infection testing algorithms (RITAs) are used in public health surveillance to estimate the incidence of recently acquired HIV-1 infection. Our aims were (i) to evaluate the precision of the VITROS® Anti-HIV 1+2 automated antibody avidity assay for qualitative detection of antibodies to HIV 1+2 virus; (ii) to validate the accuracy of an automated guanidine-based antibody avidity assay to discriminate between recent and long standing infections using the VITROS 3600 platform; (iii) to compare this method with BED-CEIA assay; and (iv) to evaluate the occurrence of false recent misclassifications by the VITROS antibody avidity assay in patients with a CD4 count <200 cells/μL and in patients on combination antiretroviral therapy (cART). The VITROS® antibody avidity assay is highly reproducible. The ROC curve analysis of the accuracy of this assay, optimized for sensitivity and specificity, had an AI cut off of ≤0.51, with sensitivity and specificity values of 86.67% (95% CI: 72.51-94.46) and 86.24% (95% CI: 78.00-91.84), respectively. The agreement between VITROS antibody avidity and BED-CEIA assays was good. Misclassifications of long standing infections as recent infection occurred in 8.2% of patients with CD4 <200 cell/μL and 8.7% in patients on combination antiretroviral therapy. The VITROS antibody avidity assay is a reliable serological method to detect recent HIV-1 infections and it could be incorporated into a RITA to estimate HIV incidence. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Microorganisms isolated from root canals presenting necrotic pulp and their drug susceptibility in vitro.

PubMed

Lana, M A; Ribeiro-Sobrinho, A P; Stehling, R; Garcia, G D; Silva, B K; Hamdan, J S; Nicoli, J R; Carvalho, M A; Farias, L de M

2001-04-01

The knowledge about causative agents involved in endodontic infections is increasing, especially due to the improvement of culture techniques for anaerobic bacteria, showing that these microorganisms are predominant in this pathology. In this study, 31 canals with pulp necrosis were microbiologically analyzed before and after manipulation. Obligate and facultative anaerobes, microaerophilic bacteria and yeasts were recovered from 24, 14, 5 and 2 clinical specimens, respectively. The most frequent genera were Prevotella, Fusobacterium, Lactobacillus, Streptococcus, Clostridium and Peptostreptococcus for bacteria and Candida and Saccharomyces for yeasts. Strong positive associations, using an odds ratio system, were found between Clostridium and Prevotella and between Peptostreptococcus and Fusobacterium. Even after the instrumentation and the use of Ca(OH)2, facultative anaerobes were detected in two root canals and yeasts in three. Microorganisms were isolated from seven canals at the end of the endodontic treatment: facultative anaerobes from five and yeasts from one. The microbiological evaluation of root canals with pulp necrosis suggests the presence of polymicrobial infections, mainly involving obligate anaerobes, and shows that the infection may persist after treatment.

Outbreak!: Teaching Clinical and Diagnostic Microbiology Methodologies with an Interactive Online Game

ERIC Educational Resources Information Center

Clark, Sherri; Smith, Geoffrey Battle

2004-01-01

Outbreak! is an online, interactive educational game that helps students and teachers learn and evaluate clinical microbiology skills. When the game was used in introductory microbiology laboratories, qualitative evaluation by students showed very positive responses and increased learning. Outbreak! allows students to design diagnostic tests and…

Microbiological and Pharmacological Evaluation of the Micropropagated Rubus liebmannii Medicinal Plant

PubMed Central

Jiménez-Arellanes, Adelina; Cornejo-Garrido, Jorge; Rojas-Bribiesca, Gabriela; Nicasio-Torres, María del Pilar; Said-Fernández, Salvador; Mata-Cárdenas, Benito David; Molina-Salinas, Gloria María; Tortoriello, Jaime; Meckes-Fischer, Mariana

2012-01-01

Rubus liebmannii is an endemic species from Mexico used in traditional medicine primarily to treat dysentery and cough. The in vitro activity against Giardia lamblia and Entamoeba histolytica that produces the ethanolic extract of the aerial parts of the plant led us to expand the pharmacological and phytochemical research of this species. Gastrointestinal disorders including amebiasis remain one of the health problems that need to be addressed and it is of interest to find alternatives that improve their treatment. Also, it is important to emphasize that R. liebmannii grows wild in the country and is not found in abundance; therefore, alternatives that avoid overexploitation of the natural resource are mandatory. Ongoing with the evaluation of the potentialities that R. liebmannii possesses for treating infectious gastrointestinal diseases, the aim of the present study was to evaluate the biological effects and the chemical composition of the micropropagated plant. PMID:22966243

76 FR 48169 - Advancing Regulatory Science for Highly Multiplexed Microbiology/Medical Countermeasure Devices...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-08

...] Advancing Regulatory Science for Highly Multiplexed Microbiology/ Medical Countermeasure Devices; Public... Regulatory Science for Highly Multiplexed Microbiology/Medical Countermeasure Devices.'' The purpose of the public meeting is to discuss performance evaluation of highly multiplexed microbiology/medical...

In Vitro Activity of Delafloxacin and Microbiological Response against Fluoroquinolone-Susceptible and Nonsusceptible Staphylococcus aureus Isolates from Two Phase 3 Studies of Acute Bacterial Skin and Skin Structure Infections

PubMed Central

Lawrence, L.; Quintas, M.; Woosley, L.; Flamm, R.; Tseng, C.; Cammarata, S.

2017-01-01

ABSTRACT Delafloxacin is an investigational anionic fluoroquinolone antibiotic with broad-spectrum in vitro activity, including activity against Gram-positive organisms, Gram-negative organisms, atypical organisms, and anaerobes. The in vitro activity of delafloxacin and the percent microbiological response in subjects infected with fluoroquinolone-susceptible and nonsusceptible Staphylococcus aureus isolates were determined from two global phase 3 studies of delafloxacin versus vancomycin plus aztreonam in patients with acute bacterial skin and skin structure infections (ABSSSI). Patients from 23 countries, predominately the United States but also Europe, South America, and Asia, were enrolled. The microbiological intent-to-treat (MITT) population included 1,042 patients from which 685 S. aureus isolates were submitted for identification and susceptibility testing per CLSI guidelines at the central laboratory (JMI Laboratories, North Liberty, IA). The comparator fluoroquinolone antibiotics included levofloxacin and ciprofloxacin. Nonsusceptibility to these antibiotics was determined using CLSI breakpoints. S. aureus isolates were 33.7% levofloxacin nonsusceptible (LVX-NS). The delafloxacin MIC90 values against levofloxacin-nonsusceptible S. aureus, methicillin-resistant S. aureus (MRSA), and methicillin-susceptible S. aureus isolates were all 0.25 μg/ml. Delafloxacin demonstrated high rates of microbiological response against LVX-NS isolates as well as isolates with documented mutations in the quinolone resistance-determining region (QRDR). S. aureus was eradicated or presumed eradicated in 98.4% (245/249) of delafloxacin-treated patients. Similar eradication rates were observed for delafloxacin-treated subjects with levofloxacin-nonsusceptible S. aureus isolates (80/81; 98.8%) and MRSA isolates (70/71; 98.6%). Microbiological response rates of 98.6% were observed with delafloxacin-treated subjects with S. aureus isolates with the S84L mutation in gyrA and the S80Y mutation in parC, the most commonly observed mutations in global phase 3 studies. The data suggest that delafloxacin could be a good option for the treatment of infections caused by S. aureus isolates causing ABSSSI, including MRSA isolates, where high rates of ciprofloxacin and levofloxacin nonsusceptibility are observed. (The phase 3 studies described in this paper have been registered at ClinicalTrials.gov under identifiers NCT01984684 and NCT01811732.) PMID:28630189

In Vitro Activity of Delafloxacin and Microbiological Response against Fluoroquinolone-Susceptible and Nonsusceptible Staphylococcus aureus Isolates from Two Phase 3 Studies of Acute Bacterial Skin and Skin Structure Infections.

PubMed

McCurdy, S; Lawrence, L; Quintas, M; Woosley, L; Flamm, R; Tseng, C; Cammarata, S

2017-09-01

Delafloxacin is an investigational anionic fluoroquinolone antibiotic with broad-spectrum in vitro activity, including activity against Gram-positive organisms, Gram-negative organisms, atypical organisms, and anaerobes. The in vitro activity of delafloxacin and the percent microbiological response in subjects infected with fluoroquinolone-susceptible and nonsusceptible Staphylococcus aureus isolates were determined from two global phase 3 studies of delafloxacin versus vancomycin plus aztreonam in patients with acute bacterial skin and skin structure infections (ABSSSI). Patients from 23 countries, predominately the United States but also Europe, South America, and Asia, were enrolled. The microbiological intent-to-treat (MITT) population included 1,042 patients from which 685 S. aureus isolates were submitted for identification and susceptibility testing per CLSI guidelines at the central laboratory (JMI Laboratories, North Liberty, IA). The comparator fluoroquinolone antibiotics included levofloxacin and ciprofloxacin. Nonsusceptibility to these antibiotics was determined using CLSI breakpoints. S. aureus isolates were 33.7% levofloxacin nonsusceptible (LVX-NS). The delafloxacin MIC 90 values against levofloxacin-nonsusceptible S. aureus , methicillin-resistant S. aureus (MRSA), and methicillin-susceptible S. aureus isolates were all 0.25 μg/ml. Delafloxacin demonstrated high rates of microbiological response against LVX-NS isolates as well as isolates with documented mutations in the quinolone resistance-determining region (QRDR). S. aureus was eradicated or presumed eradicated in 98.4% (245/249) of delafloxacin-treated patients. Similar eradication rates were observed for delafloxacin-treated subjects with levofloxacin-nonsusceptible S. aureus isolates (80/81; 98.8%) and MRSA isolates (70/71; 98.6%). Microbiological response rates of 98.6% were observed with delafloxacin-treated subjects with S. aureus isolates with the S84L mutation in gyrA and the S80Y mutation in parC , the most commonly observed mutations in global phase 3 studies. The data suggest that delafloxacin could be a good option for the treatment of infections caused by S. aureus isolates causing ABSSSI, including MRSA isolates, where high rates of ciprofloxacin and levofloxacin nonsusceptibility are observed. (The phase 3 studies described in this paper have been registered at ClinicalTrials.gov under identifiers NCT01984684 and NCT01811732.). Copyright © 2017 McCurdy et al.

76 FR 71982 - Advancing Regulatory Science for Highly Multiplexed Microbiology/Medical Countermeasure Devices...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-21

...] Advancing Regulatory Science for Highly Multiplexed Microbiology/ Medical Countermeasure Devices; Public... Multiplexed Microbiology/ Medical Countermeasure Devices'' that published in the Federal Register of August 8... the October 13, 2011, meeting, including the performance evaluation of highly multiplexed microbiology...

Activity of antimicrobial combinations against KPC-2-producing Klebsiella pneumoniae in a rat model and time-kill assay.

PubMed

Toledo, Paula Virginia Michelon; Aranha Junior, Ayrton Alves; Arend, Lavinia Nery; Ribeiro, Vanessa; Zavascki, Alexandre Prehn; Tuon, Felipe Francisco

2015-07-01

This study evaluated the efficacy of tigecycline (TIG), polymyxin B (PMB), and meropenem (MER) in 80 rats challenged with Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae infection. A time-kill assay was performed with the same strain. Triple therapy and PMB+TIG were synergistic, promoted 100% survival, and produced negative peritoneal cultures, while MER+TIG showed lower survival and higher culture positivity than other regimens (P = 0.018) and was antagonistic. In vivo and in vitro studies showed that combined regimens, except MER+TIG, were more effective than monotherapies for this KPC-producing strain. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Synthesis, Spectral Characterization, In-vitro Antibacterial and Antifungal Activities of Novel (2e)-Ethyl-2-(2-(2, 4-Dinitrophenyl) Hydrazono)-4-(Naphthalen-2-yl)-6-Arylcyclohex-3-Enecarboxylates

PubMed Central

Kanagarajan, V; Thanusu, J; Gopalakrishnan, M

2011-01-01

In a search for new leads towards potent antimicrobial agents, an array of novel (2E)-ethyl-2-(2-(2,4-dinitrophenyl)hydrazono)-4-(naphthalen-2-yl)-6-arylcyclohex-3-ene carboxylates 17-24 were synthesized and characterized through their melting point, elemental analysis, MS, FT-IR, one-dimensional NMR (1H, D2O exchanged 1H and 13C), two dimensional HOMOCOR and HSQC spectroscopic data. In-vitro microbiological evaluations were carried out for all the newly synthesized compounds 17-24 against clinically isolated bacterial strains namely Salmonella typhii, Klebsiellapneumoniae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, β-Hemolytic streptococcus and Micrococcus luteusand also fungal strains namely Aspergillusflavus, Aspergillusniger, Mucor, Rhizopus and Microsporumgypseumand finally, the results of their structure activity relationship were discussed. The obtained results can be used as the key step for the building of novel chemical compounds with interesting antimicrobial profiles comparable to that of the standard drugs. PMID:24250406

Synthesis, Spectral Characterization, In-vitro Antibacterial and Antifungal Activities of Novel (2e)-Ethyl-2-(2-(2, 4-Dinitrophenyl) Hydrazono)-4-(Naphthalen-2-yl)-6-Arylcyclohex-3-Enecarboxylates.

PubMed

Kanagarajan, V; Thanusu, J; Gopalakrishnan, M

2011-01-01

In a search for new leads towards potent antimicrobial agents, an array of novel (2E)-ethyl-2-(2-(2,4-dinitrophenyl)hydrazono)-4-(naphthalen-2-yl)-6-arylcyclohex-3-ene carboxylates 17-24 were synthesized and characterized through their melting point, elemental analysis, MS, FT-IR, one-dimensional NMR ((1)H, D2O exchanged (1)H and (13)C), two dimensional HOMOCOR and HSQC spectroscopic data. In-vitro microbiological evaluations were carried out for all the newly synthesized compounds 17-24 against clinically isolated bacterial strains namely Salmonella typhii, Klebsiellapneumoniae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, β-Hemolytic streptococcus and Micrococcus luteusand also fungal strains namely Aspergillusflavus, Aspergillusniger, Mucor, Rhizopus and Microsporumgypseumand finally, the results of their structure activity relationship were discussed. The obtained results can be used as the key step for the building of novel chemical compounds with interesting antimicrobial profiles comparable to that of the standard drugs.

In-vitro activity of ciprofloxacin combined with flomoxef against Bacteroides fragilis, compared with that of ciprofloxacin combined with clindamycin.

PubMed

Kato, Komei; Iwai, Shigetomi; Sato, Takeshi; Harada, Tomohide; Nakagawa, Yoshiteru; Iwanaga, Hitomi; Ito, Yumiko; Takayama, Tadatoshi

2002-06-01

Using checkerboard and time-kill assays, the in-vitro activity of ciprofloxacin alone and in combination with flomoxef against clinical Bacteroides fragilis strains was evaluated. In addition, the microbiological efficacy of this combination was compared with that of ciprofloxacin plus clindamycin. In 88% of the 25 strains tested, the combination of ciprofloxacin plus flomoxef exhibited a synergistic or an additive effect, whereas only 56% of the 25 strains ( P< 0.01, chi(2) test) tested with the combination of ciprofloxacin plus clindamycin exhibited similar effects. In a time-kill study using 7 clinical strains, a synergistic or additive effect of the combination of ciprofloxacin plus flomoxef was observed in all 7 strains. In conclusion, the combination of ciprofloxacin plus flomoxef is very active against B. fragilis, suggesting that this combination may be very useful in the treatment of aerobic and B. fragilis mixed infections, because ciprofloxacin has an expanded spectrum against aerobes.

Evaluation of commercial essential oil samples on the growth of postharvest pathogen Monilinia fructicola (G. Winter) Honey.

PubMed

Lazar-Baker, E E; Hetherington, S D; Ku, V V; Newman, S M

2011-03-01

To assess the effect of several commercial essential oils samples Australian lemon myrtle (Backhousia citriodora), cinnamon bark (Cinnamomum zeylanicum), oregano (Origanum vulgare), thyme oil (Thymus vulgaris), clove bud (Eugenia caryophyllata), valerian (Valeriana officinalis) and Australian tea tree oil (Melaleuca alternifolia) on mycelium growth and spore germination of Monilinia fructicola. The effectiveness of lemon myrtle essential oil as a fumigant for the control of brown rot in nectarines was evaluated. Monilinia fructicola exhibited a different level of sensitivity to each tested essential oil with results suggesting that the essential oils provide excellent control of the pathogen with respect to mycelium growth and spore germination at very low concentrations, whereas for others higher concentrations are needed to reduce significant fungal growth. In vivo application of lemon myrtle essential oil effectively reduced the incidence of M. fructicola on noninoculated fruit. Fumigation of nectarines following inoculation did not reduce the incidence of brown rot in comparison with the inoculated control treatment. No evidence of phytotoxicity on the fruit was recorded. Lemon myrtle essential oil exhibited the strongest antifungal activity against M. fructicola, in vitro and to a lesser extent, under in vivo conditions. The results demonstrate that lemon myrtle essential oil, in particular, has potential as an antifungal agent to control M. fructicola. © 2011 NSW Industry & Investment, Australia. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

[Pharmacokinetic/pharmacodynamic analysis in microbiology: a tool for the evaluation of the antimicrobial treatment].

PubMed

Canut Blasco, Andrés; Aguilar Alfaro, Lorenzo; Cobo Reinoso, Javier; Giménez Mestre, M José; Rodríguez-Gascón, Alicia

2015-01-01

The selection of multiresistant microorganisms, as a side-effect of the use of antimicrobials, together with the lack of new therapeutic drugs expected in the near future, forces to a rational use of antibiotics. The optimisation of antibacterial treatments based on pharmacokinetic/pharmacodynamic analysis (PK/PD) may contribute to prolong the life of antibiotics and to contain the bacterial resistance to them. A review is made of the importance of the appropriateness of the dose regimen selected, the application of PK/PD analysis of antimicrobials, the Monte Carlo simulation, PK/PD indices for efficacy, and PK/PD cut-off points. PK/PD analysis is also applicable to the prevention of bacterial resistance. Different methods have been used to study the factors that lead to its emergence and spread, such as in vitro and animal models, and resistance prevention studies (mutant selection window). Although the PK/PD analysis is a very useful tool for the selection of the most appropriate dose regimen of antibiotics, several problems limit its use in clinical practice. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Combination of garlic essential oil, allyl isothiocyanate, and nisin Z as bio-preservatives in fresh sausage.

PubMed

Araújo, Monyque Kais; Gumiela, Aline Marzaleck; Bordin, Keliani; Luciano, Fernando Bittencourt; Macedo, Renata Ernlund Freitas de

2018-09-01

The effects of natural antimicrobial compounds (garlic essential oil [GO], allyl isothiocyanate [AITC], and nisin Z [NI]) on microbiological, physicochemical and sensory characteristics of fresh sausage were assessed. The minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs) towards Escherichia coli O157:H7 and Lactobacillus plantarum were determined in vitro. Sausages inoculated with E. coli O157:H7, were treated with different combinations of antimicrobials and assessed for microbiological and physicochemical parameters during storage (6C for 20 d). Treatments that presented the greatest antimicrobial effects were subjected to sensory evaluation. Combinations of 20 mg/kg NI + 125 μL/kg GO + 62.5 μL/kg AITC or 20 mg/kg NI + 62.5 μL/kg GO + 125 μL/kg AITC were effective in reducing E. coli O157H7 and spoilage lactic acid bacteria, and maintained the physicochemical characteristics of fresh sausage. Combinations of NI, GO and AITC were effective to improve the safety and the shelf life of fresh sausage, with no impact on its sensory acceptance. Copyright © 2018 Elsevier Ltd. All rights reserved.

Assessment of the in vitro bioactive properties of lactic acid bacteria isolated from native ecological niches of Ecuador.

PubMed

Benavides, Ana B; Ulcuango, Mario; Yépez, Lucía; Tenea, Gabriela N

Lactic acid bacteria are known for their biotechnological potential. In various regions of Ecuador numerous indigenous biological resources are largely undocumented. In this study, we evaluated the potential probiotic characteristics and antagonistic in vitro properties of some lactic acid bacteria from native niches of the subtropical rain forests of Ecuador. These isolates were identified according to their morphological properties, standard API50CH fermentation profile and RAPD-DNA polymorphism pattern. The selected isolates were further evaluated for their probiotic potential. The isolates grew at 15°C and 45°C, survived at a pH ranging from 2.5 to 4.5 in the presence of 0.3% bile (>90%) and grew under sodium chloride conditions. All selected isolates were sensitive to ampicillin, amoxicillin and cefuroxime and some showed resistance to gentamicin, kanamycin and tetracycline. Moreover, the agar well diffusion assay showed that the supernatant of each strain at pH 3.0 and pH 4.0, but not at pH 7.0 exhibited increased antimicrobial activity (inhibition zone >15mm) against two foodborne pathogens, Escherichia coli and Salmonella spp. To our knowledge, this is the first report describing the antagonistic activity against two foodborne pathogens and the probiotic in vitro potential of lactic acid bacteria isolated from native biota of Ecuador. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Characterization and evaluation of lactic acid bacteria candidates for intestinal epithelial permeability and Salmonella Typhimurium colonization in neonatal turkey poults.

PubMed

Yang, Y; Latorre, J D; Khatri, B; Kwon, Y M; Kong, B W; Teague, K D; Graham, L E; Wolfenden, A D; Mahaffey, B D; Baxter, M; Hernandez-Velasco, X; Merino-Guzman, R; Hargis, B M; Tellez, G

2018-02-01

The present study evaluated the microbiological properties of three probiotic candidate strains of lactic acid bacteria (LAB) (128; 131; CE11_2), their effect on intestinal epithelial permeability, and their ability to reduce intestinal colonization of Salmonella Typhimurium (ST) individually or as a batch culture in neonatal turkey poults. Isolates were characterized morphologically and identified using 16S rRNA sequence analyses. Each isolate was evaluated for tolerance and resistance to acidic pH, high osmotic NaCl concentrations, and bile salts in broth medium. In vitro assessment of antimicrobial activity against different enteropathogenic bacteria was determined using an overlay technique. In vitro intestinal permeability was evaluated using a stressed Caco-2 cell culture assay treated with/without the probiotic candidates. The in vivo effect of the selected LAB strains on ST cecal colonization was determined in two independent trials with neonatal turkey poults. The results obtained in this study demonstrate the tolerance of LAB candidates to pH 3, a NaCl concentration of 6.5%, and high bile salts (0.6%). All strains evaluated exhibited in vitro antibacterial activity against Salmonella Enteritidis, ST, and Campylobacter jejuni. Candidates 128 and 131 exhibited a coccus morphology and were identified as Enterococcus faecium, and bacterial strain CE11_2 exhibited clusters of cocci-shaped cells and was identified as Pediococcus parvulus. All three candidate probiotics significantly (P < 0.05) increased transepithelial electrical resistance (TEER) in Caco-2 cells following a 3-h incubation period with hydrogen peroxide compared to control and blank groups. The combination of all three candidates as a batch culture exhibited significant efficacy in controlling intestinal colonization of ST in neonatal turkey poults. Evaluation of the combination of these selected LAB strains according to performance and intestinal health parameters of chickens and turkeys are currently in process. © 2017 Poultry Science Association Inc.

In vitro microbiological evaluation of novel bis pyrazolones.

PubMed

Narayana Rao, D V; Raghavendra Guru Prasad, A; Spoorthy, Y N; Raghunatha Rao, D; Ravindranath, L K

2014-03-01

Two series of bis pyrazolones (one with 3-methyl substituent and the other one with 3-amino substituent on the pyrazolone ring) were synthesized by the cyclization reaction between various hydrazides with esters/cyano esters in ethanolic medium. Structures of newly synthesized compounds were confirmed by elemental analysis, IR, (1)H NMR and mass spectral data. These compounds were screened for antibacterial and antifungal activities. The compounds of series 3 with amino substituent demonstrated better activity than the compounds of series 2 with methyl substituent on the pyrazolone ring. Compounds "e, f, c and d" showed higher antimicrobial activity than the compounds "b and a". The antimicrobial potentials of the synthesized compounds were compared with that of standards. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

[First Argentine consensus guidelines for in vitro antimicrobial susceptibility testing of clinically relevant anaerobic bacteria in humans/ Anaerobic Subcommittee of the Asociación Argentina de Microbiología].

PubMed

Legaria, María C; Bianchini, Hebe M; Castello, Liliana; Carloni, Graciela; Di Martino, Ana; Fernández Canigia, Liliana; Litterio, Mirta; Rollet, Raquel; Rossetti, Adelaida; Predari, Silvia C

2011-01-01

Through time, anaerobic bacteria have shown good susceptibility to clinically useful antianaerobic agents. Nevertheless, the antimicrobial resistance profile of most of the anaerobic species related to severe infections in humans has been modified in the last years and different kinds of resistance to the most active agents have emerged, making their effectiveness less predictable. With the aim of finding an answer and for the purpose of facilitating the detection of anaerobic antimicrobial resistance, the Anaerobic Subcommittee of the Asociación Argentina de Microbiología developed the First Argentine consensus guidelines for in vitro antimicrobial susceptibility testing of clinically relevant anaerobic bacteria in humans. This document resulted from the compatibilization of the Clinical and Laboratory Standards Institute recommendations, the international literature and the work and experience of the Subcommittee. The Consensus document provides a brief taxonomy review, and exposes why and when anaerobic antimicrobial susceptibility tests should be conducted, and which antimicrobial agents can be used according to the species involved. The recommendations on how to perform, read and interpret in vitro anaerobic antimicrobial susceptibility tests with each method are exposed. Finally, the antibiotic susceptibility profile, the classification of antibiotics according to their in vitro activities, the natural and acquired mechanisms of resistance, the emerging resistance and the regional antibiotic resistance profile of clinically relevant anaerobic species are shown.

Utility of antimicrobial susceptibility testing in Trichomonas vaginalis-infected women with clinical treatment failure.

PubMed

Bosserman, Elizabeth A; Helms, Donna J; Mosure, Debra J; Secor, W Evan; Workowski, Kimberly A

2011-10-01

Antimicrobial resistance is one of the causes of treatment failure in women after standard nitroimidazole therapy for Trichomonas vaginalis infections. The Centers for Disease Control and Prevention provides drug susceptibility testing and guidance for treatment failures but the efficacy of the alternate recommendations has not been assessed. T. vaginalis isolates from women who had failed at least 2 courses of standard therapy for trichomoniasis were submitted to the Centers for Disease Control and Prevention for susceptibility testing. Alternative treatment recommendations were provided based on in vitro drug susceptibility results and clinical outcomes were collected. Drug susceptibility results were available for 175 women tested between January 2002 and January 2008. In vitro, 115 of the 175 isolates demonstrated metronidazole resistance. For all isolates resistant to metronidazole, in vitro resistance to tinidazole was similar or lower. Clinical treatment outcomes were available for 72 women. Of the women receiving an alternative recommended nitroimidazole regimen, 30 (83%) of 36 were cured compared with 8 (57%) of 14 women who received a lower dose than recommended. Clinical and microbiologic success was attained in 59 (82%) of 72 women whose follow-up information was available, with some women requiring multiple treatment courses. Clinical and microbiologic cure rates were higher for women who were treated in accordance with the recommendation provided after in vitro testing compared with those who received a lower dose or a different drug. Susceptibility testing leading to tailored treatment may have a beneficial role for management of women with persistent trichomoniasis.

Antimicrobial Testing Methods & Procedures: MB-10-06

EPA Pesticide Factsheets

Describes the procedures used to log-in, prepare, and evaluate the quality of media and reagents used in microbiological assays by the Microbiology Laboratory Branch (MLB), for use in the quality evaluation of media and reagents used by MLB.

In silico and in vitro screening to identify structurally diverse non-azole CYP51 inhibitors as potent antifungal agent.

PubMed

Singh, Aarti; Paliwal, Sarvesh Kumar; Sharma, Mukta; Mittal, Anupama; Sharma, Swapnil; Sharma, Jai Prakash

2016-01-01

The problem of resistance to azole class of antifungals is a serious cause of concern to the medical fraternity and thus there is an urgent need to identify non-azole scaffolds with high affinity for lanosterol 14α-demethylase (CYP51). In view of this we have attempted to identify novel non-azole CYP51 inhibitors through the application of pharmacophore based virtual screening and in vitro evaluation. A rigorously validated pharmacophore model comprising of 2 hydrogen bond acceptor and 2 hydrophobic features has been developed and used to mine NCI database. Out of 265 retrieved hits, NSC 1215 and 1520 have been chosen on the basis of Lipinski's rule of five, fit and estimated values. Both the hits were docked into the active site of CYP51. In view of high fit value and CDocker score, NSC 1215 and 1520 have been subjected to in vitro microbiological assay. The result reveals that NSC 1215 and 1520 are active against Candida albicans, Candida parapsilosis, Candida tropicalis, and Aspergillus niger. In addition to this the absorption characteristics of both the hits have also been determined using the rat sac technique and permeation in order of NSC 1520>NSC 1215 has been observed. Copyright © 2015 Elsevier Inc. All rights reserved.

Postmortem in vitro ethanol production-It could be more common than we think!

PubMed

Quintas, Maria José; Costa, Pedro; Melo, Paula; Castro, André; Franco, João Miguel; Teixeira, Helena M

2017-05-01

The blood alcohol concentration (BAC) is the most frequent determination in a Forensic Toxicology Laboratory. Despite its apparent simplicity, the results interpretation can be complex and always have relevant social and legal implications, particularly in postmortem analysis. In the present report we describe the case of a 55-year-old male with an apparent natural death by myocardial infarction, whose initial BAC was 0.18g/L but, in repeated determinations prompted by discrepancies observed in the first two, it rapidly increased to 0.85g/L three days later, leading to the suspicion of in vitro ethanol production. A microbiological examination of the sample revealed the presence of the bacteria Escherichia coli and Enterococcus faecalis, and yeast Candida parapsilosis, known for their involvement in ethanol production. Although this is a case report and it is not meant to be generalizable, we discuss an existing large body of scientific literature showing the difficulties, limitations and some relevant medico-legal questions regarding BAC determinations in postmortem samples and their interpretation, particularly in the context of plausible in vitro ethanol production. The key conclusion is that evaluating a postmortem BAC is a complex and multifactorial process that always deserves a thorough analysis and a careful interpretation. Copyright © 2017 Elsevier B.V. All rights reserved.

In vitro activity of glucosinolates and their degradation products against brassica-pathogenic bacteria and fungi.

PubMed

Sotelo, T; Lema, M; Soengas, P; Cartea, M E; Velasco, P

2015-01-01

Glucosinolates (GSLs) are secondary metabolites found in Brassica vegetables that confer on them resistance against pests and diseases. Both GSLs and glucosinolate hydrolysis products (GHPs) have shown positive effects in reducing soil pathogens. Information about their in vitro biocide effects is scarce, but previous studies have shown sinigrin GSLs and their associated allyl isothiocyanate (AITC) to be soil biocides. The objective of this work was to evaluate the biocide effects of 17 GSLs and GHPs and of leaf methanolic extracts of different GSL-enriched Brassica crops on suppressing in vitro growth of two bacterial (Xanthomonas campestris pv. campestris and Pseudomonas syringae pv. maculicola) and two fungal (Alternaria brassicae and Sclerotinia scletoriorum) Brassica pathogens. GSLs, GHPs, and methanolic leaf extracts inhibited the development of the pathogens tested compared to the control, and the effect was dose dependent. Furthermore, the biocide effects of the different compounds studied were dependent on the species and race of the pathogen. These results indicate that GSLs and their GHPs, as well as extracts of different Brassica species, have potential to inhibit pathogen growth and offer new opportunities to study the use of Brassica crops in biofumigation for the control of multiple diseases. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Fungal CYP51 Inhibitors VT-1161 and VT-1129 Exhibit Strong In Vitro Activity against Candida glabrata and C. krusei Isolates Clinically Resistant to Azole and Echinocandin Antifungal Compounds.

PubMed

Schell, W A; Jones, A M; Garvey, E P; Hoekstra, W J; Schotzinger, R J; Alexander, B D

2017-03-01

The in vitro activities of fungal CYP51 inhibitors VT-1161 and VT-1129 were determined for Candida glabrata ( n = 34) and C. krusei ( n = 50). C. glabrata isolates were screened for FKS gene mutations. All isolates were resistant clinically and/or in vitro to at least one standard antifungal compound. VT-1161 and VT-1129 MICs for all isolates were at least 5-fold below achievable human plasma levels for VT-1161. VT-1161 and VT-1129 are promising for the treatment of resistant C. glabrata and C. krusei infections. Copyright © 2017 American Society for Microbiology.

Integrated Evaluation Concept to Assess the Efficacy of Advanced Wastewater Treatment Processes for the Elimination of Micropollutants and Pathogens.

PubMed

Ternes, Thomas A; Prasse, Carsten; Eversloh, Christian Lütke; Knopp, Gregor; Cornel, Peter; Schulte-Oehlmann, Ulrike; Schwartz, Thomas; Alexander, Johannes; Seitz, Wolfram; Coors, Anja; Oehlmann, Jörg

2017-01-03

A multidisciplinary concept has been developed to compare advanced wastewater treatment processes for their efficacy of eliminating micropollutants and pathogens. The concept is based on (i) the removal/formation of selected indicator substances and their transformation products (TPs), (ii) the assessment of ecotoxicity via in vitro tests, and (iii) the removal of pathogens and antibiotic resistant bacteria. It includes substances passing biological wastewater treatment plants regulated or proposed to be regulated in the European Water Framework Directive, TPs formed in biological processes or during ozonation, agonistic/antagonistic endocrine activities, mutagenic/genotoxic activities, cytotoxic activities, further activities like neurotoxicity as well as antibiotics resistance genes, and taxonomic gene markers for pathogens. At a pilot plant, ozonation of conventionally treated wastewater resulted in the removal of micropollutants and pathogens and the reduction of estrogenic effects, whereas the in vitro mutagenicity increased. Subsequent post-treatment of the ozonated water by granular activated carbon (GAC) significantly reduced the mutagenic effects as well as the concentrations of remaining micropollutants, whereas this was not the case for biofiltration. The results demonstrate the suitability of the evaluation concept to assess processes of advanced wastewater treatment including ozonation and GAC by considering chemical, ecotoxicological, and microbiological parameters.

Pharmacokinetics and Preliminary Safety of Pod-Intravaginal Rings Delivering the Monoclonal Antibody VRC01-N for HIV Prophylaxis in a Macaque Model.

PubMed

Zhao, Chunxia; Gunawardana, Manjula; Villinger, Francois; Baum, Marc M; Remedios-Chan, Mariana; Moench, Thomas R; Zeitlin, Larry; Whaley, Kevin J; Bohorov, Ognian; Smith, Thomas J; Anderson, Deborah J; Moss, John A

2017-07-01

The broadly neutralizing antibody (bNAb) VRC01, capable of neutralizing 91% of known human immunodeficiency virus type 1 (HIV-1) isolates in vitro , is a promising candidate microbicide for preventing sexual HIV infection when administered topically to the vagina; however, accessibility to antibody-based prophylactic treatment by target populations in sub-Saharan Africa and other underdeveloped regions may be limited by the high cost of conventionally produced antibodies and the limited capacity to manufacture such antibodies. Intravaginal rings of the pod design (pod-IVRs) delivering Nicotiana -manufactured VRC01 (VRC01-N) over a range of release rates have been developed. The pharmacokinetics and preliminary safety of VRC01-N pod-IVRs were evaluated in a rhesus macaque model. The devices sustained VRC01-N release for up to 21 days at controlled rates, with mean steady-state VRC01-N levels in vaginal fluids in the range of 10 2 to 10 3 μg g -1 being correlated with in vitro release rates. No adverse safety indications were observed. These findings indicate that pod-IVRs are promising devices for the delivery of the candidate topical microbicide VRC01-N against HIV-1 infection and merit further preclinical evaluation. Copyright © 2017 American Society for Microbiology.

Ex-vivoand in-vitro assessment of mucoadhesive patches containing the gel-forming polysaccharide psyllium for buccal delivery of chlorhexidine base.

PubMed

Cavallari, Cristina; Brigidi, Patrizia; Fini, Adamo

2015-12-30

The aim of the present study was to evaluate the gel-forming polysaccharide psyllium in the preparation of mucoadhesive patches for the controlled release of chlorhexidine (CHX) to treat pathologies in the oral cavity, using the casting-solvent evaporation technique. A number of different film-forming semi-synthetic polymers, such as sodium carboxymethyl cellulose (SCMC) and hydroxypropylmethyl cellulose (HPMC) were evaluated for comparison. The patch formulations were characterized in terms of drug content, morphology surface, swelling and mucoadhesive properties, microbiology inhibition assay and in vitro release tests. Three ex-vivo testswere carried out using porcine mucosa: an alternative dissolution test using artificial saliva that allows contemporary measurement of dissolution and mucoadhesion, a permeation test through the mucosa and the measurement of mucoadhesion using a Nouy tensile tester, as the maximum force required for the separation of the patch from the mucosa surface. The patches were also examined for determination of the minimum inhibitory concentration in cultures of Escherichia coli and Staphylococcus aureus. All the patches incorporating psyllium were found suitable in terms of external morphology, mucoadhesion and controlled release of the drug: in the presence of psyllium the drug displays prolonged zero-order release related to slower swelling rate of the system. Copyright © 2015. Published by Elsevier B.V.

Saccharomyces cerevisiae from Brazilian kefir-fermented milk: An in vitro evaluation of probiotic properties.

PubMed

Lima, Meire Dos Santos Falcão de; Souza, Karoline Mirella Soares de; Albuquerque, Wendell Wagner Campos; Teixeira, José António Couto; Cavalcanti, Maria Taciana Holanda; Porto, Ana Lúcia Figueiredo

2017-09-01

The therapeutic use of probiotics for supporting the antibiotic action against gastrointestinal disorders is a current trend and emerging applications have gained popularity because of their support for various microbiological activities in digestive processes. Microorganisms isolated from kefir with great probiotic properties, in addition to high resistance to harsh environmental conditions, have been widely researched. Administration of probiotic yeasts offers a number of advantages, when compared to bacteria, because of particular characteristics as their larger cell size. In the present study, 28 strains of Saccharomyces cerevisiae were isolated, after in vitro digestion of kefir-fermented milk, and identified by molecular based approaches. A screening was performed to determine important quality requirements for probiotics including: antagonistic and antioxidant activities, β-galactosidase synthesis, autoaggregation, surface hydrophobicity and adhesion to epithelial cells. The results showed strains: with antagonistic activity against microbial pathogens such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis; able to produce β-galactosidase; with antioxidant activity levels higher than 90%; with hydrophobicity activity and autoaggregation ability (evaluated by adhesion test, where all the strains presented adhesion to mice ileal epithelial cells). These findings are relevant and the strains are recommended for further in vivo studies as well as for potential therapeutic applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Microbiological evaluation of chronic blepharitis among Iranian veterans exposed to mustard gas: a case-controlled study.

PubMed

Karimian, Farid; Zarei-Ghanavati, Siamak; A, Baradaran-Rafii; Jadidi, Khosrow; Lotfi-Kian, Alireza

2011-06-01

To evaluate the microbiological characteristics of eyelid margin flora in chronic blepharitis in mustard gas-exposed individuals and compare the results with those in age- and sex-matched unexposed people. In this comparative case series, 289 patients with ocular manifestations of mustard gas exposure (case) were evaluated for signs of chronic blepharitis. Additionally, microbiological evaluation of eyelid margins was conducted in these patients and compared with results of 100 unexposed patients with chronic blepharitis (control). One-hundred fifty (52.0%) of 289 mustard gas casualties had signs of chronic blepharitis. Microbiological evaluation revealed higher isolation rates of Staphylococcus epidermidis (78%) and Staphylococcus aureus (57%) in the case in comparison to control group (P < 0.01). Moreover, S. aureus isolated from the cases exhibited greater resistance to common antibiotics compared with control group. Fungi were isolated more frequent in the case compared with controls (30% vs. 4%, P < 0.01), with Cladosporium and Candida species being most common in the case group. Exposure to mustard gas seems to alter the microbiological flora of the eyelid margin. Staphylococcus spp., including antibiotic-resistant strains, and fungi were more frequently isolated in these patients. The relationship between microbial culture results and the severity of ocular surface manifestations in mustard gas-injured cases warrant further investigation.

In Vitro Susceptibility of the Relapsing-Fever Spirochete Borrelia miyamotoi to Antimicrobial Agents.

PubMed

Koetsveld, Joris; Draga, Ronald O P; Wagemakers, Alex; Manger, Annemijn; Oei, Anneke; Visser, Caroline E; Hovius, Joppe W

2017-09-01

Hard-tick-borne relapsing fever (HTBRF) is an emerging infectious disease throughout the temperate zone caused by the relapsing-fever spirochete Borrelia miyamotoi Antibiotic treatment of HTBRF is empirically based on the treatment of Lyme borreliosis; however, the antibiotic susceptibility of B. miyamotoi has not been studied to date. Thus, we set out to determine the in vitro antimicrobial susceptibility of B. miyamotoi A microdilution method with 96-well microtiter plates was used to determine the antibiotic susceptibilities of two B. miyamotoi strains isolated on two different continents (Asia and North America), two Borrelia burgdorferi sensu lato strains, and one Borrelia hermsii isolate for purposes of comparison. The MIC and minimal bactericidal concentration (MBC) were determined by both microscopy and colorimetric assays. We were able to show that relative to the B. burgdorferi sensu lato isolates, both B. miyamotoi strains and B. hermsii demonstrated greater susceptibility to doxycycline and azithromycin, equal susceptibility to ceftriaxone, and resistance to amoxicillin in vitro The MIC and MBC of amoxicillin for B. miyamotoi evaluated by microscopy were 16 to 32 mg/liter and 32 to 128 mg/liter, respectively. Since B. miyamotoi is susceptible to doxycycline, azithromycin, and ceftriaxone in vitro , our data suggest that these antibiotics can be used for the treatment of HTBRF. Oral amoxicillin is currently used as an alternative for the treatment of HTBRF; however, since we found that the B. miyamotoi strains tested were resistant to amoxicillin in vitro , this issue warrants further study. Copyright © 2017 American Society for Microbiology.

[In vitro susceptibility of Trichoconiella padwickii to various active ingredients used as fungicides in the cultivation of rice].

PubMed

Lovato Echeverria, Alfonso D; Gutiérrez, Susana A; Carmona, Marcelo A

The aim of this study was to evaluate in vitro the mycelial susceptibility of Trichoconiella padwickii to different active ingredients through average median concentration IC 50 calculation. Inoculum disks were seeded on bean agar at different concentrations (0.1; 1; 10; 30, 50; 100 and 1000mg/l) of various fungicides. After seven days the colony diameter was measured. The data obtained were fitted to nonlinear regression models. Susceptibility was classified using the scale proposed by Edgington. The results show that the pathogen is very sensitive to products that act on the respiratory chain (quinone outside inhibitors [QoI] and succinate dehydrogenase inhibitors [SDHI]) and cell membrane (multi-site contact activity), and moderately sensitive to those products interfering with cell division (methyl benzimidazole carbamates [MBC]), synthesis of nucleic acids (phenylamides [PA]) and osmotic signal transduction (multi-site contact activity). This work is the first record on the sensitivity of T. padwickii. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

In vitro and in vivo evaluation of 28DAP010, a novel diamidine for treatment of second-stage African sleeping sickness.

PubMed

Wenzler, Tanja; Yang, Sihyung; Patrick, Donald A; Braissant, Olivier; Ismail, Mohamed A; Tidwell, Richard R; Boykin, David W; Wang, Michael Zhuo; Brun, Reto

2014-08-01

African sleeping sickness is a neglected tropical disease transmitted by tsetse flies. New and better drugs are still needed especially for its second stage, which is fatal if untreated. 28DAP010, a dipyridylbenzene analogue of DB829, is the second simple diamidine found to cure mice with central nervous system infections by a parenteral route of administration. 28DAP010 showed efficacy similar to that of DB829 in dose-response studies in mouse models of first- and second-stage African sleeping sickness. The in vitro time to kill, determined by microcalorimetry, and the parasite clearance time in mice were shorter for 28DAP010 than for DB829. No cross-resistance was observed between 28DAP010 and pentamidine on the tested Trypanosoma brucei gambiense isolates from melarsoprol-refractory patients. 28DAP010 is the second promising preclinical candidate among the diamidines for the treatment of second-stage African sleeping sickness. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Acetic acid as a decontamination method for sink drains in a nosocomial outbreak of metallo-β-lactamase-producing Pseudomonas aeruginosa.

PubMed

Stjärne Aspelund, A; Sjöström, K; Olsson Liljequist, B; Mörgelin, M; Melander, E; Påhlman, L I

2016-09-01

Pseudomonas aeruginosa may colonize water systems via biofilm formation. In hospital environments, contaminated sinks have been associated with nosocomial transmission. Here we describe a prolonged outbreak of a metallo-β-lactamase-producing P. aeruginosa (Pae-MBL) associated with sink drains, and propose a previously unreported decontamination method with acetic acid. To describe a nosocomial outbreak of Pae-MBL associated with hospital sink drains and to evaluate acetic acid as a decontamination method. The outbreak was investigated by searching the microbiology database, microbiological sampling and strain typing. Antibacterial and antibiofilm properties of acetic acid were evaluated in vitro. Pae-MBL-positive sinks were treated with 24% acetic acid once weekly and monitored with repeated cultures. Fourteen patients with positive cultures for Pae-MBL were identified from 2008 to 2014. The patients had been admitted to three wards, where screening discovered Pae-MBL in 12 sink drains located in the patient bathrooms. Typing of clinical and sink drain isolates revealed identical or closely related strains. Pae-MBL biofilm was highly sensitive to acetic acid with a minimum biofilm eradication concentration of 0.75% (range: 0.19-1.5). Weekly treatment of colonized sink drains with acetic acid resulted in negative cultures and terminated transmission. Acetic acid is highly effective against Pae-MBL biofilms, and may be used as a simple method to decontaminate sink drains and to prevent nosocomial transmission. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Competency assessment of microbiology medical laboratory technologists in Ontario, Canada.

PubMed

Desjardins, Marc; Fleming, Christine Ann

2014-08-01

Accreditation in Ontario, Canada, requires that licensed clinical laboratories participate in external quality assessment (also known as proficiency testing) and perform competency evaluation of their staff. To assess the extent of ongoing competency assessment practices, the Quality Management Program--Laboratory Services (QMP-LS) Microbiology Committee surveyed all 112 licensed Ontario microbiology laboratories. The questionnaire consisted of a total of 21 questions that included yes/no, multiple-choice, and short-answer formats. Participants were asked to provide information about existing programs, the frequency of testing, what areas are evaluated, and how results are communicated to the staff. Of the 111 responding laboratories, 6 indicated they did not have a formal evaluation program since they perform only limited bacteriology testing. Of the remaining 105 respondents, 87% perform evaluations at least annually or every 2 years, and 61% include any test or task performed, whereas 16% and 10% focus only on problem areas and high-volume complex tasks, respectively. The most common methods of evaluation were review of external quality assessment (EQA) challenges, direct observation, and worksheet review. With the exception of one participant, all communicate results to staff, and most take remedial action to correct the deficiencies. Although most accredited laboratories have a program to assess the ongoing competency of their staff, the methods used are not standardized or consistently applied, indicating that there is room for improvement. The survey successfully highlighted potential areas for improvement and allowed the QMP-LS Microbiology Committee to provide guidance to Ontario laboratories for establishing or improving existing microbiology-specific competency assessment programs. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

IN VITRO BIOTRANSFOMATION OF AN ARSENOSUGAR BY MOUSE ANAEROBIC CECAL MICROFLORA AND CECAL TISSUE EXAMINED USING IC-ICP-MS AND LC-ESI-MS/MS

EPA Science Inventory

This investigation examined chemical and microbiological transformations of an arsenosugar by mouse cecum. To mimic the low oxygen environment in the mammalian gastrointestinal tract, reaction mixtures were incubated under anaerobic conditions. An arsenosugar extracted from ribbo...

Enhanced antibacterial properties, biocompatibility, and corrosion resistance of degradable Mg-Nd-Zn-Zr alloy.

PubMed

Qin, Hui; Zhao, Yaochao; An, Zhiquan; Cheng, Mengqi; Wang, Qi; Cheng, Tao; Wang, Qiaojie; Wang, Jiaxing; Jiang, Yao; Zhang, Xianlong; Yuan, Guangyin

2015-06-01

Magnesium (Mg), a potential biodegradable material, has recently received increasing attention due to its unique antibacterial property. However, rapid corrosion in the physiological environment and potential toxicity limit clinical applications. In order to improve the corrosion resistance meanwhile not compromise the antibacterial activity, a novel Mg alloy, Mg-Nd-Zn-Zr (Hereafter, denoted as JDBM), is fabricated by alloying with neodymium (Nd), zinc (Zn), zirconium (Zr). pH value, Mg ion concentration, corrosion rate and electrochemical test show that the corrosion resistance of JDBM is enhanced. A systematic investigation of the in vitro and in vivo antibacterial capability of JDBM is performed. The results of microbiological counting, CLSM, SEM in vitro, and microbiological cultures, histopathology in vivo consistently show JDBM enhanced the antibacterial activity. In addition, the significantly improved cytocompatibility is observed from JDBM. The results suggest that JDBM effectively enhances the corrosion resistance, biocompatibility and antimicrobial properties of Mg by alloying with the proper amount of Zn, Zr and Nd. Copyright © 2015 Elsevier Ltd. All rights reserved.

Critical Appraisal of Microbiology Guidelines Endorsed by two Professional Organisations: Société Française De Microbiologie (SFM) and American Society of Microbiology (ASM).

PubMed

Fonfrède, Michèle; Couaillac, Jean Paul; Augereau, Christine; Lepargneur, Jean Pierre; Watine, Joseph

2012-07-01

Medical practice guidelines (GLs) being tools that are mainly designed to evaluate medical professionals, it sounds logical, and fair, that professionals should in turn evaluate GLs. Microbiology being a medical discipline, we used the AGREE instrument, i.e. an established evaluation tool for GLs, in order to evaluate the quality of two major microbiology guidelines, i.e. the SFM GLs and the ASM GLs). Both guidelines remain sub-optimal in their levels of quality, and obtain scores that are not very different from the average scores obtained by many other guidelines in various medical disciplines. We therefore believe that both guidelines need to be modified before they can be recommended without provisos. A higher degree of multi-disciplinary work, including a more formal implication of methodologists, as well as of infectious disease clinicians, and of economists, might perhaps enable future editions of these guidelines to reach higher levels of quality.

Comparing different methods for fast screening of microbiological quality of beach sand aimed at rapid-response remediation.

PubMed

Testolin, Renan C; Almeida, Tito C M; Polette, Marcus; Branco, Joaquim O; Fischer, Larissa L; Niero, Guilherme; Poyer-Radetski, Gabriel; Silva, Valéria C; Somensi, Cleder A; Corrêa, Albertina X R; Corrêa, Rogério; Rörig, Leonardo R; Itokazu, Ana Gabriela; Férard, Jean-François; Cotelle, Sylvie; Radetski, Claudemir M

2017-05-15

There is scientific evidence that beach sands are a significant contributor to the pathogen load to which visitors are exposed. To develop beach quality guidelines all beach zones must be included in microbiological evaluations, but monitoring methods for beach sand quality are relatively longstanding, expensive, laborious and require moderate laboratory infrastructure. This paper aimed to evaluate the microorganism activity in different beach zones applying and comparing a classical method of membrane filtration (MF) with two colorimetric screening methods based on fluorescein (FDA) and tetrazolium (TTC) salt biotransformation to evaluate a new rapid and low-cost method for beach sand microbiological contamination assessments. The colorimetric results can help beach managers to evaluate rapidly and at low cost the microbiological quality of different beach zones in order to decide whether remedial actions need to be adopted to prevent exposure of the public to microbes due to beach sand and/or water contamination. Copyright © 2017. Published by Elsevier Ltd.

[Evaluation of the quality of poultry meat and its processing for vacuum packaging].

PubMed

Swiderski, F; Russel, S; Waszkiewicz-Robak, B; Cholewińska, E

1997-01-01

The aim of study was to evaluate the quality of poultry meat, roasted and smoked chicken and poultry pie packing under low and high vacuum. All investigated products were stored at +4 degrees C and evaluated by microbiological analysis. It was showed that packing under low and high vacuum inhibited development of aerobic microorganisms, proteolytic bacteria, yeasts and moulds. Vacuum-packaged storage of poultry meat and its products stimulated activity of anaerobic, nonsporeforming bacteria. The fast spoilage of fresh poultry meat was observed both under vacuum and conventional storage. The microbiology quality of poultry products depended on technology of production and microbiological quality of raw material.

Evaluation of the Microbiological Status of Raw Beef in Korea: Considering the Suitability of Aerobic Plate Count Guidelines

PubMed Central

Kim, Hye-Jin; Kim, Dongwook; Kim, Hee-Jin; Song, Sung-Ok; Song, Young-Han; Jang, Aera

2018-01-01

This study was conducted to analyze the microbiological contamination status of raw beef distributed in Korea, and evaluate the suitability of current aerobic plate count (APC) guidelines. We analyzed five years (2010-2014) of microbiological monitoring data obtained from the Ministry of Food and Drug Safety and investigated the microbiological status of raw beef collected from meat packing centers and meat shops in the Seoul/Gyeonggi, Gangwon, and Chungcheong regions in August 2015. From 2010-2014, most raw beef (>94%) displayed APC levels of < 1.0 × 106 CFU/g. However, raw beef samples collected from all three regions in August 2015 had comparatively higher APC levels than those reported in previous years. To evaluate the relationship between the APC level and quality, changes in beef loin were evaluated during cold storage for 15 days at 4°C. On day 11, the mean APC level (4.7 × 106 CFU/g) conformed to current guidelines in Korea (1.0 × 107 CFU/g) and the pH value was 5.82. However, the sensory evaluation score for color and overall acceptability was under 3.0, meaning that the beef loin was not acceptable for eating. These results suggest that current APC guideline for raw beef should be lowered to 1.0 × 106 CFU/g to improve both the microbiological safety and palatability of raw beef. PMID:29725223

[Authorized Qualifications of Staff Conducting Examinations in the Field of Clinical Microbiology].

PubMed

Nishiyama, Hiroyuki

2015-04-01

Because of the increase in healthcare-associated infections, appearance of highly resistant bacteria, and that of emerging/re-emerging infectious diseases, it is necessary for the skills of clinical microbiological technologists and the associated technology to be improved. Technologist in Microbiology (4,717 certified) and Specialist in Microbiology (58 certified) are authorized qualifications in the field of examination for clinical microbiology, with a history of 60 years, and Clinical Microbiological Technologist (670 certified) and Infection Control Microbiological Technologist (ICMT) (528 certified) are necessary qualifications to become a member of an infection control team. As problems to be resolved, clarifying the relationships among the authorized qualifications, reconsidering the fairness of evaluating written examinations, and further consideration of the administration method for an increasing number of examinees need to be tackled.

Antimicrobial evaluation of novel poly-lactic acid based nanocomposites incorporated with bioactive compounds in-vitro and in refrigerated vacuum-packed cooked sausages.

PubMed

Rezaeigolestani, Mohammadreza; Misaghi, Ali; Khanjari, Ali; Basti, Afshin Akhondzadeh; Abdulkhani, Ali; Fayazfar, Samira

2017-11-02

Biodegradability and antimicrobial activity of food packaging materials are among the most attractive parameters in modern food industries. In order to develop biodegradable poly-lactic acid (PLA) film to antibacterial nanocomposites, different concentration of Zataria multiflora Bioss. essential oil (ZME), propolis ethanolic extract (PEE) and cellulose nanofiber (CNF) were incorporated to the polymer by solvent casting method. The resulting films were characterized by mechanical and physical tests and their antimicrobial application was evaluated in-vitro against four common foodborne pathogens and in vacuum-packed cooked sausages during refrigerated storage. Mechanical examination revealed that addition of ZME and PEE made films more flexible and incorporation of CNF improved almost all mechanical parameters tested. Moreover, according to physical analysis, incorporation of 0.5% v/v ZME to the composite primary solutions improved water vapor permeability of the resulting films. Almost all of the active films were effective against the tested bacteria except for PLA/PEE films, and maximum antibacterial effects recorded for the films containing both ZME and PEE. Based on the microbiological and sensory evaluation of the sausages, all of the PLA/1%ZME/PEE composites increased the shelf life to >40days. The results indicate that incorporation of natural antimicrobial substances such as ZME and PEE to packaging material could be an interesting approach in development of active packaging material without significant negative effect on polymer technical properties. Copyright © 2017 Elsevier B.V. All rights reserved.

Biological availability and in vitro dissolution of oxytetracycline dihydrate tablets

PubMed Central

Barber, H. E.; Calvey, T. N.; Muir, K.; Hart, A.

1974-01-01

1 The concentration of oxytetracycline in plasma was studied by microbiological assay after oral administration of four different preparations of oxytetracycline dihydrate tablets. 2 There were statistically significant differences in biological availability between the four preparations, as assessed by the peak plasma level, the area under the plasma concentration-time curve, or the cumulative fraction of the dose excreted in urine at 405 minutes. In contrast, differences between the subjects were not statistically significant. 3 The differences in biological availability were not predictably related to the in vitro dissolution of the tablets. PMID:22454918

In Vitro Antifungal Susceptibility Profiles of 12 Antifungal Drugs against 55 Trichophyton schoenleinii Isolates from Tinea Capitis Favosa Patients in Iran, Turkey, and China.

PubMed

Deng, Shuwen; Ansari, Saham; Ilkit, Macit; Rafati, Haleh; Hedayati, Mohammad T; Taghizadeh-Armaki, Mojtaba; Nasrollahi-Omran, Ayatollah; Tolooe, Ali; Zhan, Ping; Liao, Wanqing; van der Lee, Henrich A; Verweij, Paul E; Seyedmousavi, Seyedmojtaba

2017-02-01

Trichophyton schoenleinii is an anthropophilic dermatophyte mainly causing tinea favosa of the scalp in certain regions of the world, especially Africa and Asia. We investigated the in vitro susceptibilities of 55 T. schoenleinii isolates collected over the last 30 years from Iran, Turkey, and China to 12 antifungals using the CLSI broth microdilution method. Our results revealed that terbinafine and ketoconazole were the most potent antifungal agents among those tested, independently of the geographic regions where strains were isolated. Copyright © 2017 American Society for Microbiology.

In vitro efficacy of brincidofovir against variola virus.

PubMed

Olson, Victoria A; Smith, Scott K; Foster, Scott; Li, Yu; Lanier, E Randall; Gates, Irina; Trost, Lawrence C; Damon, Inger K

2014-09-01

Brincidofovir (CMX001), a lipid conjugate of the acyclic nucleotide phosphonate cidofovir, is under development for smallpox treatment using "the Animal Rule," established by the FDA in 2002. Brincidofovir reduces mortality caused by orthopoxvirus infection in animal models. Compared to cidofovir, brincidofovir has increased potency, is administered orally, and shows no evidence of nephrotoxicity. Here we report that the brincidofovir half-maximal effective concentration (EC50) against five variola virus strains in vitro averaged 0.11 μM and that brincidofovir was therefore nearly 100-fold more potent than cidofovir. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Europe Report, Science and Technology.

DTIC Science & Technology

1986-06-06

the question, of course , whether the combined treatment will cause chromosome damage. In the case of chromosomes from in vitro cultivated human ...latest acquisition, this division collaborates to major engine programs, in particular with Snecma ( Atar , CFM 56) and Turbomeca (ARTM 405). 9294 CSO...microbiology, enzymology, molecular and cell biology , organic chemistry, etc. Several large public research organizations are involved: CNRS [National

Comparison of different incubation conditions for microbiological environmental monitoring.

PubMed

Gordon, Oliver; Berchtold, Manfred; Staerk, Alexandra; Roesti, David

2014-01-01

Environmental monitoring represents an integral part of the microbiological quality control system of a pharmaceutical manufacturing operation. However, guidance documents differ regarding recommendation of a procedure, particularly regarding incubation time, incubation temperature, or nutrient media. Because of these discrepancies, many manufacturers decide for a particular environmental monitoring sample incubation strategy and support this decision with validation data. Such validations are typically laboratory-based in vitro studies, meaning that these are based on comparing incubation conditions and nutrient media through use of cultured microorganisms. An informal survey of the results of these in vitro studies performed at Novartis or European manufacturing sites of different pharmaceutical companies highlighted that no consensus regarding the optimal incubation conditions for microbial recovery existed. To address this question differently, we collected a significant amount of samples directly from air, inanimate surfaces, and personnel in pharmaceutical production and packaging rooms during manufacturing operation (in situ study). Samples were incubated under different conditions suggested in regulatory guidelines, and recovery of total aerobic microorganisms as well as moulds was assessed. We found the highest recovery of total aerobic count from areas with personnel flow using a general microbiological growth medium incubated at 30-35 °C. The highest recovery of moulds was obtained with mycological medium incubated at 20-25 °C. Single-plate strategies (two-temperature incubation or an intermediate incubation temperature of 25-30 °C) also yielded reasonable recovery of total aerobic count and moulds. However, recovery of moulds was found to be highly inefficient at 30-35 °C compared to lower incubation temperatures. This deficiency could not be rectified by subsequent incubation at 20-25 °C. A laboratory-based in vitro study performed in parallel was inconclusive. We consider our results potentially conferrable to other pharmaceutical manufacturing sites in moderate climate zones and believe that these should represent a valuable reference for definition of the incubation strategy of microbiological environmental monitoring samples. Microbiological environmental monitoring confirms that pharmaceutical cleanrooms are in an appropriate hygienic condition for manufacturing of drug products. Guidance documents from different health authorities or expert groups differ regarding recommendation of the applied incubation time, incubation temperature, or nutrient media. Therefore, many pharmaceutical manufacturers perform studies that aim to identify the optimal incubation setup for environmental monitoring samples. An informal survey of the results of such studies, which had been performed at Novartis or European manufacturing sites of different pharmaceutical companies, highlighted no consensus regarding the optimal incubation conditions for microbial recovery. All these studies had been conducted in the laboratory using selections of cultured microbial strains. We tried to solve this disagreement by collecting a significant amount of real environmental monitoring samples directly from the environment in pharmaceutical production and packaging rooms during manufacturing operation. These samples were then incubated under different conditions suggested in the regulatory guidelines. We believe that the results of our study are more meaningful than laboratory-based experiments because we used environmental samples with microorganisms directly isolated from the manufacturing area. Therefore, we believe that our results should represent a valuable reference for definition of the incubation strategy of microbiological environmental monitoring samples. © PDA, Inc. 2014.

[Laboratory unification: advantages and disadvantages for clinical microbiology].

PubMed

Andreu, Antonia; Matas, Lurdes

2010-10-01

This article aims to reflect on which areas or tasks of microbiology laboratories could be unified with those of clinical biochemistry, hematology, immunology or pathology laboratories to benefit patients and the health system, as well as the areas that should remain independent since their amalgamation would not only fail to provide a benefit but could even jeopardize the quality of microbiological diagnosis, and consequently patient care. To do this, the distinct analytic phases of diagnosis are analyzed, and the advantages and disadvantages of amalgamation are evaluated in each phase. The pros and cons of the unification of certain areas such as the computer system, occupational risk units, customer service, purchasing logistics, and materials storage, etc, are also discussed. Lastly, the effect of unification on urgent microbiology diagnosis is analyzed. Microbiological diagnosis should be unique. The microbiologist should perform an overall evaluation of the distinct techniques used for a particular patient, both those that involve direct diagnosis (staining, culture, antigen detection techniques or molecular techniques) and indirect diagnosis (antibody detection). Moreover, the microbiology laboratory should be independent, with highly trained technicians and specialists in microbiology that provide added value as experts in infection and as key figures in the process of establishing a correct etiological diagnosis. Copyright © 2010 Elsevier España S.L. All rights reserved.

Experiments with Writing to Teach Microbiology.

ERIC Educational Resources Information Center

Cannon, Robert E.

1990-01-01

Described are the experiences of one teacher with the teaching of writing in college level microbiology, virology, and immunology courses. Assignments, methods, evaluation, and student responses are discussed. (CW)

Learning Medical Microbiology and Infectious Diseases by Means of a Board Game: Can It Work?

ERIC Educational Resources Information Center

Struwig, Magdalena C.; Beylefeld, Adriana A.; Joubert, Georgina

2014-01-01

Innovative teaching and learning is increasingly becoming part of medical education. We report the evaluation of a medical microbiology board game, Med Micro Fun With Facts (MMFWF), based on Trivial Pursuit™ principles. The game was developed to stimulate medical students' interest in microbiology and expose students to the subject content of an…

Er:YAG laser: antimicrobial effects in the root canals of dogs' teeth with pulp necrosis and chronic periapical lesions.

PubMed

Leonardo, Mário R; Guillén-Carías, M G; Pécora, J D; Ito, I Y; Silva, L A B

2005-06-01

Our goal in this study was to evaluate the antimicrobial effect of Er:YAG laser applied after biomechanical preparation of the root canals of dog's teeth with apical periodontitis. Various in vitro studies have reported effective bacterial reduction in infected root canals using Er:YAG laser. However, there is no in vivo research to support these results. Forty root canals of dogs' premolar teeth with pulp necrosis and chronic periapical lesions were used. An initial microbiological sample was taken, and after biomechanical preparation was carried out, a second microbiological sample was taken. The teeth were divided into two groups: Group I-biomechanical preparation was taken of root canals without Er:YAG laser application; Group II-biomechanical preparation was taken of root canals with Er:YAG laser application using 140-mJ input, 63-mJ output/15 Hz. After coronal sealing, the root canals were left empty for 7 days at which time a third microbiological sample was taken. The collected material was removed from the root canal with a #40 K file and placed in transport media. It was serially diluted and seeded on culture dishes selective for anaerobes, aerobes, and total streptococci. Colony-forming units per milliliter (CFU/mL) were counted. Groups I and II showed an increase of CFU/mL for all microorganisms 7 days after treatment, being statistically significant for anaerobes in Group I and for anaerobes and total streptococci in Group II. When comparing CFU/mL of Groups I and II, there was a statistically significant increase after 7 d for total streptococci in Group II. Er:YAG laser applied after biomechanical preparation did not reduce microorganisms in the root canal system.

Aerobic microbiology and culture sensitivity of head and neck space infection of odontogenic origin

PubMed Central

Shah, Amit; Ramola, Vikas; Nautiyal, Vijay

2016-01-01

Context: Head and neck space infections source, age, gender, tooth involved, fascial spaces involved, microbiological study of aerobic flora, and antibiotic susceptibilities. Aims: The aim of the present study is to identify causative aerobic microorganisms responsible for deep fascial spaces of head and neck infections and evaluate the resistance of antibiotics used in the treatment of such. Settings and Design: Prospective study in 100 patients. Materials and Methods: This prospective study was conducted on 100 patients who reported in the outpatient department and fulfilled the inclusion criteria to study aerobic microbiology and antibiotic sensitivity in head and neck space infection of odontogenic origin. Pus sample was obtained either by aspiration or by swab stick from the involved spaces, and culture and sensitivity tests were performed. Statistical Analysis Used: Chi-square test and level of significance. Results: Result showed aerobic Gram-positive isolates were 73% and aerobic Gram-negative isolates were 18%. Nine percent cases showed no growth. Streptococcus viridans was the highest isolate in 47% cases among Gram-positive bacteria, and in Gram-negative, Klebsiella pneumoniae was the highest isolate of total cases 11%. Amoxicillin showed resistance (48.4%) as compared to other antibiotics such as ceftriaxone, carbenicillin, amikacin, and imipenem had significantly higher sensitivity. Conclusions: Amoxicillin with clavulanic acid showed (64.8%) efficacy for all organisms isolated, whereas ceftriaxone showed (82.4%) efficacy and could be used in odontogenic infections for both Gram-positive and Gram-negative microorganisms. Substitution of third generation cephalosporin for amoxicillin in the empirical management of deep fascial space infections can also be used. Carbenicillin, amikacin, and imipenem showed (93.4%) sensitivity against all microorganisms and should be reserved for more severe infection. Newer and broad-spectrum antibiotics are more effective in vitro than older narrow spectrum antibiotics. PMID:28163480

Microbiological investigations

NASA Technical Reports Server (NTRS)

Ferguson, J. K.; Taylor, G. R.; Mieszkuc, B. J.

1975-01-01

The crew microbiology program was conducted to evaluate lunar contamination, to detect potentially pathogenic microoganisms, to identify medically important microorganisms recovered from ill crewmen, to aid in diagnosis and treatment, and to collect microbiological data that would aid in elucidating the response of the crew microbial autoflora to the space flight environment and in evaluating the resultant effect on the crewmember. Microbiological sampling of selected sites in the command module was initiated in support of the quarantine program. During lunar quarantine missions, microbial screening was accomplished for all support personnel to be isolated with the returning crewman. Virology support for the Apollo project consisted of characterization of the viral and mycoplasma flora of the crewmembers and performance of viral serology for crewmembers, crew contacts, and key mission personnel. Procedures and results are discussed in detail.

Novel jojoba oil-based emulsion gel formulations for clotrimazole delivery.

PubMed

Shahin, Mostafa; Hady, Seham Abdel; Hammad, Mohammed; Mortada, Nahed

2011-03-01

Jojoba oil-based emulgel formulations were prepared using different concentrations of various gelling agents, such as hydroxypropyl methylcellulose (HPMC) and Carbopol 934 P and combination of both. The prepared emulgels were physically evaluated for their stability after temperature cycle test, centrifugation and long-term shelf storage for 1 year at room temperature. The in vitro release at 37 °C was studied to define the effect of the concentration and type of the gelling agent. A comparison between the formulated emulgels and two commercially available products, Candistan® and Canesten® creams, was carried out to judge their efficacy and stability. The prepared emulgels exhibited non-Newtonian shear thinning behavior with little or no thixotropy. Four emulgels showed excellent stability as they demonstrated consistent rheological model under different treatment conditions. The in vitro release test showed variation in the extent of percent drug released. The drug release from the commercial preparation was lower than some of the prepared emulgel formulae. One formula containing combination of the two gelling agents (HPMC and Carbopol 934 P), showed excellent stability and high extent of clotrimazole release was microbiologically evaluated against Candida albicans using cylinder and plate method. The selected formula showed superior antimycotic activity compared to the commercially available formulation. Further in vivo animal studies for the obtained stable formula is recommended. © 2011 American Association of Pharmaceutical Scientists

Effect of xantham gum, steviosides, clove, and cinnamon essential oils on the sensory and microbiological quality of a low sugar tomato jam.

PubMed

Gliemmo, María F; Montagnani, María A; Schelegueda, Laura I; González, Malena M; Campos, Carmen A

2016-03-01

The partial or total decrease of sugar content in the formulation of jams affects their physical, chemical and microbiological stability. In order to minimize these technological problems, we studied the effect of xanthan gum (XG), steviosides, cinnamon (CO), and clove (CLO) essential oils on the sensory and microbiological quality of a low sugar tomato jam. Levels of 0.250 g/100 g steviosides and 0.450 g/100 g XG showed maximum score of overall acceptability of jam. The combination of essential oils produced synergistic and additive effects in vitro on growth of Z. bailii and Z. rouxii, respectively. However, in the jam, CO was more effective and CLO did not modify the CO action. Cell surface was one of the sites of action of CO since a decrease in yeast cell surface hydrophobicity was observed. From the microbiological and sensory points of view, 0.0060 g/100 g CO showed the maximum score of jam overall acceptability and did not cause yeast inactivation but it could be useful as an additional stress factor against yeast post--process contamination. The adequate levels of XG, steviosides, and CO can improve the quality of a low sugar jam formulation. © The Author(s) 2015.

Bacterial Biofilms in Chronic Rhinosinusitis and Their Implications for Clinical Management.

PubMed

Karunasagar, Abhilasha; Garag, Santosh S; Appannavar, Suma B; Kulkarni, Raghavendra D; Naik, Ashok S

2018-03-01

To study the microbiological profile in patients with chronic rhino-sinusitis. To correlate disease severity with the presence of biofilms and host risk factors. To assess outcome of Sinus Surgery 2 weeks post operatively in terms of presence of bacteria and their ability to form biofilm. Prospective study. 50 cases of chronic rhino-sinusitis requiring Functional Endoscopic Sinus Surgery admitted in SDM Hospital, Dharwad, Karnataka were studied using intra-operative mucosal samples for microbiological analysis. The organisms isolated were tested for biofilm forming ability using three in vitro tests. Severity of disease was assessed using SNOT 22 scoring system. Of 50 cases studied, 66% showed presence of chronic rhino-sinusitis with polyposis and had higher SNOT scores compared to those without polyps. Bacterial isolates were obtained from only 17 samples. Staphylococcus species was isolated from 16 samples and Klebsiella pneumoniae from one. 11 Staph spp. isolates showed biofilm forming ability in vitro. Postoperative events in 3 cases yielded biofilm-forming Staphylococcus. Staphylococcus was the most dominant organism isolated and 11 isolates were biofilm formers. Thus the detection of biofilm forming organisms can be considered as a negative prognostic indicator and should forewarn the surgeon about the risk of recurrence.

Evaluation of Two Surface Sampling Methods for Microbiological and Chemical Analyses To Assess the Presence of Biofilms in Food Companies.

PubMed

Maes, Sharon; Huu, Son Nguyen; Heyndrickx, Marc; Weyenberg, Stephanie van; Steenackers, Hans; Verplaetse, Alex; Vackier, Thijs; Sampers, Imca; Raes, Katleen; Reu, Koen De

2017-12-01

Biofilms are an important source of contamination in food companies, yet the composition of biofilms in practice is still mostly unknown. The chemical and microbiological characterization of surface samples taken after cleaning and disinfection is very important to distinguish free-living bacteria from the attached bacteria in biofilms. In this study, sampling methods that are potentially useful for both chemical and microbiological analyses of surface samples were evaluated. In the manufacturing facilities of eight Belgian food companies, surfaces were sampled after cleaning and disinfection using two sampling methods: the scraper-flocked swab method and the sponge stick method. Microbiological and chemical analyses were performed on these samples to evaluate the suitability of the sampling methods for the quantification of extracellular polymeric substance components and microorganisms originating from biofilms in these facilities. The scraper-flocked swab method was most suitable for chemical analyses of the samples because the material in these swabs did not interfere with determination of the chemical components. For microbiological enumerations, the sponge stick method was slightly but not significantly more effective than the scraper-flocked swab method. In all but one of the facilities, at least 20% of the sampled surfaces had more than 10 2 CFU/100 cm 2 . Proteins were found in 20% of the chemically analyzed surface samples, and carbohydrates and uronic acids were found in 15 and 8% of the samples, respectively. When chemical and microbiological results were combined, 17% of the sampled surfaces were contaminated with both microorganisms and at least one of the analyzed chemical components; thus, these surfaces were characterized as carrying biofilm. Overall, microbiological contamination in the food industry is highly variable by food sector and even within a facility at various sampling points and sampling times.

Selection of antagonistic bacteria isolated from the Physalis peruviana rhizosphere against Fusarium oxysporum.

PubMed

Urrea, R; Cabezas, L; Sierra, R; Cárdenas, M; Restrepo, S; Jiménez, P

2011-09-01

Cape gooseberries (Physalis peruviana) have become increasingly important in Colombia for both domestic consumption and the international export market. Vascular wilting caused by Fusarium oxysporum is the most damaging disease to P. peruviana crops in Colombia. The control of this pathogen is mainly carried out by chemical and cultural practices, increasing production costs and generating resistance. Therefore, the objectives of this study were to test rhizobacteria isolates from P. peruviana rhizosphere against F. oxysporum under in vitro and in vivo conditions. Over 120 strains were isolated, and five were selected for their high inhibition of F. oxysporum growth and conidia production under in vitro conditions. These strains inhibited growth by 41-58% and reduced three- to fivefold conidia production. In the in vivo assays, all the tested isolates significantly reduced fungal pathogenicity in terms of virulence. Isolate B-3.4 was the most efficient in delaying the onset of the first symptoms. All isolates were identified as belonging to the genus Pseudomonas except for A-19 (Bacillus sp.). Our results confirmed that there are prospective rhizobacteria strains that can be used as biological control agents; some of them being able to inhibit in vitro F. oxysporum growth and sporulation. Incorporating these bacteria into biological control strategies for the disease that causes high economical losses in the second most exported fruit from Colombia would result in a reduced impact on environment and economy. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Addressing Therapeutic Options for Ebola Virus Infection in Current and Future Outbreaks.

PubMed

Haque, Azizul; Hober, Didier; Blondiaux, Joel

2015-10-01

Ebola virus can cause severe hemorrhagic disease with high fatality rates. Currently, no specific therapeutic agent or vaccine has been approved for treatment and prevention of Ebola virus infection of humans. Although the number of Ebola cases has fallen in the last few weeks, multiple outbreaks of Ebola virus infection and the likelihood of future exposure highlight the need for development and rapid evaluation of pre- and postexposure treatments. Here, we briefly review the existing and future options for anti-Ebola therapy, based on the data coming from rare clinical reports, studies on animals, and results from in vitro models. We also project the mechanistic hypotheses of several potential drugs against Ebola virus, including small-molecule-based drugs, which are under development and being tested in animal models or in vitro using various cell types. Our paper discusses strategies toward identifying and testing anti-Ebola virus properties of known and medically approved drugs, especially those that can limit the pathological inflammatory response in Ebola patients and thereby provide protection from mortality. We underline the importance of developing combinational therapy for better treatment outcomes for Ebola patients. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

In Vitro and In Vivo Synergy of the Oxadiazole Class of Antibacterials with β-Lactams.

PubMed

Janardhanan, Jeshina; Meisel, Jayda E; Ding, Derong; Schroeder, Valerie A; Wolter, William R; Mobashery, Shahriar; Chang, Mayland

2016-09-01

The oxadiazole antibacterials target the bacterial cell wall and are bactericidal. We investigated the synergism of ND-421 with the commonly used β-lactams and non-β-lactam antibiotics by the checkerboard method and by time-kill assays. ND-421 synergizes well with β-lactam antibiotics, and it also exhibits a long postantibiotic effect (4.7 h). We also evaluated the in vivo efficacy of ND-421 in a murine neutropenic thigh infection model alone and in combination with oxacillin. ND-421 has in vivo efficacy by itself in a clinically relevant infection model (1.49 log10 bacterial reduction for ND-321 versus 0.36 log10 for linezolid with NRS119) and acts synergistically with β-lactam antibiotics in vitro and in vivo, and the combination of ND-421 with oxacillin is efficacious in a mouse neutropenic thigh methicillin-resistant Staphylococcus aureus (MRSA) infection model (1.60 log10 bacterial reduction). The activity of oxacillin was potentiated in the presence of ND-421, as the strain would have been resistant to oxacillin otherwise. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

In Vitro Efficacy of Nonantibiotic Treatments on Biofilm Disruption of Gram-Negative Pathogens and an In Vivo Model of Infectious Endometritis Utilizing Isolates from the Equine Uterus.

PubMed

Ferris, Ryan A; McCue, Patrick M; Borlee, Grace I; Loncar, Kristen D; Hennet, Margo L; Borlee, Bradley R

2016-03-01

In this study, we evaluated the ability of the equine clinical treatments N-acetylcysteine, EDTA, and hydrogen peroxide to disrupt in vitro biofilms and kill equine reproductive pathogens (Escherichia coli, Pseudomonas aeruginosa, or Klebsiella pneumoniae) isolated from clinical cases. N-acetylcysteine (3.3%) decreased biofilm biomass and killed bacteria within the biofilms of E. coli isolates. The CFU of recoverable P. aeruginosa and K. pneumoniae isolates were decreased, but the biofilm biomass was unchanged. Exposure to hydrogen peroxide (1%) decreased the biofilm biomass and reduced the CFU of E. coli isolates, K. pneumoniae isolates were observed to have a reduction in CFU, and minimal effects were observed for P. aeruginosa isolates. Chelating agents (EDTA formulations) reduced E. coli CFU but were ineffective at disrupting preformed biofilms or decreasing the CFU of P. aeruginosa and K. pneumoniae within a biofilm. No single nonantibiotic treatment commonly used in equine veterinary practice was able to reduce the CFU and biofilm biomass of all three Gram-negative species of bacteria evaluated. An in vivo equine model of infectious endometritis was also developed to monitor biofilm formation, utilizing bioluminescence imaging with equine P. aeruginosa isolates from this study. Following infection, the endometrial surface contained focal areas of bacterial growth encased in a strongly adherent "biofilm-like" matrix, suggesting that biofilms are present during clinical cases of infectious equine endometritis. Our results indicate that Gram-negative bacteria isolated from the equine uterus are capable of producing a biofilm in vitro, and P. aeruginosa is capable of producing biofilm-like material in vivo. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Delamanid Kills Dormant Mycobacteria In Vitro and in a Guinea Pig Model of Tuberculosis.

PubMed

Chen, Xiuhao; Hashizume, Hiroyuki; Tomishige, Tatsuo; Nakamura, Izuru; Matsuba, Miki; Fujiwara, Mamoru; Kitamoto, Ryuki; Hanaki, Erina; Ohba, Yoshio; Matsumoto, Makoto

2017-06-01

Tuberculosis (TB) treatment is long and requires multiple drugs, likely due to various phenotypes of TB bacilli with variable drug susceptibilities. Drugs with broad activity are urgently needed. This study aimed to evaluate delamanid's activity against growing or dormant bacilli in vitro as well as in vivo Cultures of Mycobacterium bovis BCG Tokyo under aerobic and anaerobic conditions were used to study the activity of delamanid against growing and dormant bacilli, respectively. Delamanid exhibited significant bactericidal activity against replicating and dormant bacilli at or above concentrations of 0.016 and 0.4 mg/liter, respectively. To evaluate delamanid's antituberculosis activity in vivo , we used a guinea pig model of chronic TB infection in which the lung lesions were similar to those in human TB disease. In the guinea pig TB model, a daily dose of 100 mg delamanid/kg of body weight for 4 or 8 weeks demonstrated strong bactericidal activity against Mycobacterium tuberculosis Importantly, histological examination revealed that delamanid killed TB bacilli within hypoxic lesions of the lung. The combination regimens containing delamanid with rifampin and pyrazinamide or delamanid with levofloxacin, ethionamide, pyrazinamide, and amikacin were more effective than the standard regimen (rifampin, isoniazid, and pyrazinamide). Our data show that delamanid is effective in killing both growing and dormant bacilli in vitro and in the guinea pig TB model. Adding delamanid to current TB regimens may improve treatment outcomes, as demonstrated in recent clinical trials with pulmonary multidrug-resistant (MDR) TB patients. Delamanid may be an important drug for consideration in the construction of new regimens to shorten TB treatment duration. Copyright © 2017 American Society for Microbiology.

In Vitro Assessment of Combined Polymyxin B and Minocycline Therapy against Klebsiella pneumoniae Carbapenemase (KPC)-Producing K. pneumoniae.

PubMed

Huang, Dennis; Yu, Brenda; Diep, John K; Sharma, Rajnikant; Dudley, Michael; Monteiro, Jussimara; Kaye, Keith S; Pogue, Jason M; Abboud, Cely Saad; Rao, Gauri G

2017-07-01

The multidrug resistance profiles of Klebsiella pneumoniae carbapenemase (KPC) producers have led to increased clinical polymyxin use. Combination therapy with polymyxins may improve treatment outcomes, but it is uncertain which combinations are most effective. Clinical successes with intravenous minocycline-based combination treatments have been reported for infections caused by carbapenemase-producing bacteria. The objective of this study was to evaluate the in vitro activity of polymyxin B and minocycline combination therapy against six KPC-2-producing K. pneumoniae isolates (minocycline MIC range, 2 to 32 mg/liter). Polymyxin B monotherapy (0.5, 1, 2, 4, and 16 mg/liter) resulted in a rapid reduction of up to 6 log in bactericidal activity followed by regrowth by 24 h. Minocycline monotherapy (1, 2, 4, 8, and 16 mg/liter) showed no reduction of activity of >1.34 log against all isolates, although concentrations of 8 and 16 mg/liter prolonged the time to regrowth. When the therapies were used in combination, rapid bactericidal activity was followed by slower regrowth, with synergy (60 of 120 combinations at 24 h, 19 of 120 combinations at 48 h) and additivity (43 of 120 combinations at 24 h, 44 of 120 combinations at 48 h) against all isolates. The extent of killing was greatest against the more susceptible polymyxin B isolates (MICs of ≤0.5 mg/liter) regardless of the minocycline MIC. The pharmacodynamic activity of combined polymyxin B-minocycline therapy against KPC-producing K. pneumoniae is dependent on polymyxin B susceptibility. Further in vitro and animal studies must be performed to fully evaluate the efficacy of this drug combination. Copyright © 2017 American Society for Microbiology.

A Single Amino Acid Substitution in the NS2A Protein of Japanese Encephalitis Virus Affects Virus Propagation In Vitro but Not In Vivo.

PubMed

Takamatsu, Yuki; Morita, Kouichi; Hayasaka, Daisuke

2015-06-01

We identified a unique amino acid of NS2A113, phenylalanine, that affects the efficient propagation of two Japanese encephalitis virus strains, JaTH160 and JaOArS982, in neuroblastoma Neuro-2a cells but not in cell lines of extraneural origin. This amino acid did not affect viral loads in the brain or survival curves in mice. These findings suggest that virus propagation in vitro may not reflect the level of virus neuroinvasiveness in vivo. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

In vitro activity of wALADin benzimidazoles against different life cycle stages of Plasmodium parasites.

PubMed

Lentz, Christian S; Sattler, Julia M; Fendler, Martina; Gottwalt, Simon; Halls, Victoria S; Strassel, Silke; Arriens, Sandra; Hannam, Jeffrey S; Specht, Sabine; Famulok, Michael; Mueller, Ann-Kristin; Hoerauf, Achim; Pfarr, Kenneth M

2015-01-01

wALADin1 benzimidazoles are specific inhibitors of δ-aminolevulinic acid dehydratase from Wolbachia endobacteria of filarial nematodes. We report that wALADin1 and two derivatives killed blood stage Plasmodium falciparum in vitro (50% inhibitory concentrations, 39, 7.7, and 12.8 μM, respectively). One of these derivatives inhibited gliding motility of Plasmodium berghei ANKA infectious sporozoites with nanomolar affinity and blocked invasion into hepatocytes but did not affect intrahepatocytic replication. Hence, wALADin1 benzimidazoles are tools to study gliding motility and potential antiplasmodial drug candidates. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Competency Assessment of Microbiology Medical Laboratory Technologists in Ontario, Canada

PubMed Central

Fleming, Christine Ann

2014-01-01

Accreditation in Ontario, Canada, requires that licensed clinical laboratories participate in external quality assessment (also known as proficiency testing) and perform competency evaluation of their staff. To assess the extent of ongoing competency assessment practices, the Quality Management Program—Laboratory Services (QMP-LS) Microbiology Committee surveyed all 112 licensed Ontario microbiology laboratories. The questionnaire consisted of a total of 21 questions that included yes/no, multiple-choice, and short-answer formats. Participants were asked to provide information about existing programs, the frequency of testing, what areas are evaluated, and how results are communicated to the staff. Of the 111 responding laboratories, 6 indicated they did not have a formal evaluation program since they perform only limited bacteriology testing. Of the remaining 105 respondents, 87% perform evaluations at least annually or every 2 years, and 61% include any test or task performed, whereas 16% and 10% focus only on problem areas and high-volume complex tasks, respectively. The most common methods of evaluation were review of external quality assessment (EQA) challenges, direct observation, and worksheet review. With the exception of one participant, all communicate results to staff, and most take remedial action to correct the deficiencies. Although most accredited laboratories have a program to assess the ongoing competency of their staff, the methods used are not standardized or consistently applied, indicating that there is room for improvement. The survey successfully highlighted potential areas for improvement and allowed the QMP-LS Microbiology Committee to provide guidance to Ontario laboratories for establishing or improving existing microbiology-specific competency assessment programs. PMID:24899030

Ethnopharmacological surveys and pharmacological studies of plants used in traditional medicine in the treatment of HIV/AIDS opportunistic diseases in Gabon.

PubMed

Tchouya, Guy Raymond Feuya; Souza, Alain; Tchouankeu, Jean Claude; Yala, Jean-Fabrice; Boukandou, Marlaine; Foundikou, Hibrahim; Obiang, Giresse Delphang Nguema; Boyom, Fabrice Fekam; Mabika, Rolande Mabika; Menkem, Elisabeth Zeuko'o; Ndinteh, Derek Tantoh; Lebibi, Jacques

2015-03-13

Ethnopharmacological surveys were conducted in two regions of Gabon. This led to highlighting some of the medicinal plants used by local populations in the management of HIV/AIDS opportunistic diseases. Two regions with the highest occurrence of HIV/AIDS cases were visited and ethnopharmarcological data was gathered. These regions were the Estuaire Province (Libreville and its neighborhood) and the Haut-Ogooué Province (Franceville and its neighborhood). The opportunistic diseases and symptomatic conditions considered during this study were: diarrhea, respiratory tract infections, cough, tuberculosis, abscesses, stomach ache, skin rashes, venereal diseases, typhoid fever, anemia, general tiredness, hepatitis and vomiting. The reported species were evaluated through three parameters: specificity, reliability and frequency. Plant parts of relevant species were harvested and extracted with an aqueous alcohol solution (ethanol/water: 1/1). The extracts obtained were submitted to phytochemical screening and in vitro microbiological assays on some clinical isolates and ATCC strains, involved in HIV/AIDS opportunistic diseases through the Agar well diffusion and Microbroth dilution methods. Among the 52 species identified during this survey, Coelocaryon klainei Pierre ex Heckel (Myristicaceae), Dacryodes klaineana (Pierre) H.J. Lam (Bursecaceae), Phyllanthus diandrus Pax (Euphorbiaceae), Saccoglotys gabonensis (Baill.) Urb. (Humiriaceae) and Tetrorchidium didymostemon (Baill.) Pax & K. Hoffm. (Euphorbiaceae) were submitted to in vitro microbiological assays. Phyllanthus diandrus bark and leaves show best antibacterial activities against Pseudomonas aeruginosa and Klebsiella pneumoniae with MIC value of 0.25 respectively. Phytochemical screening revealed the presence in all the plant parts extracts of potentially bioactive molecules, including polyphenols, especially flavonoids and tannins. It is concluded that some of these plants might be submitted to further scientific studies, including the identification and isolation of bioactive principles, that could be developed to drugs for the treatment of HIV/AIDS opportunistic diseases. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Evaluation of indigenous bacterial strains for biocontrol of the frogeye leaf spot of soya bean caused by Cercospora sojina.

PubMed

Simonetti, E; Carmona, M A; Scandiani, M M; García, A F; Luque, A G; Correa, O S; Balestrasse, K B

2012-08-01

Assessment of biological control of Cercospora sojina, causal agent of frogeye leaf spot (FLS) of soya bean, using three indigenous bacterial strains, BNM297 (Pseudomonas fluorescens), BNM340 and BNM122 (Bacillus amyloliquefaciens). From cultures of each bacterial strain, cell suspensions and cell-free supernatants were obtained and assayed to determine their antifungal activity against C. sojina. Both mycelial growth and spore germination in vitro were more strongly inhibited by bacterial cell suspensions than by cell-free supernatants. The Bacillus strains BNM122 and BNM340 inhibited the fungal growth to a similar degree (I ≈ 52-53%), while cells from P. fluorescens BNM297 caused a lesser reduction (I ≈ 32-34%) in the fungus colony diameter. The foliar application of the two Bacillus strains on soya bean seedlings, under greenhouse conditions, significantly reduced the disease severity with respect to control soya bean seedlings and those sprayed with BNM297. This last bacterial strain was not effective in controlling FLS in vivo. Our data demonstrate that the application of antagonistic bacteria may be a promising and environmentally friendly alternative to control the FLS of soya bean.   To our knowledge, this is the first report of biological control of C. sojina by using native Bacillus strains. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

Analysis of nanomechanical properties of Borrelia burgdorferi spirochetes under the influence of lytic factors in an in vitro model using atomic force microscopy.

PubMed

Tokarska-Rodak, Małgorzata; Kozioł-Montewka, Maria; Skrzypiec, Krzysztof; Chmielewski, Tomasz; Mendyk, Ewaryst; Tylewska-Wierzbanowska, Stanisława

2015-11-12

Atomic force microscopy (AFM) is an experimental technique which recently has been used in biology, microbiology, and medicine to investigate the topography of surfaces and in the evaluation of mechanical properties of cells. The aim of this study was to evaluate the influence of the complement system and specific anti-Borrelia antibodies in in vitro conditions on the modification of nanomechanical features of B. burgdorferi B31 cells. In order to assess the influence of the complement system and anti-Borrelia antibodies on B. burgdorferi s.s. B31 spirochetes, the bacteria were incubated together with plasma of identified status. The samples were applied on the surface of mica disks. Young's modulus and adhesive forces were analyzed with a NanoScope V, MultiMode 8 AFM microscope (Bruker) by the PeakForce QNM technique in air using NanoScope Analysis 1.40 software (Bruker). The average value of flexibility of spirochetes' surface expressed by Young's modulus was 10185.32 MPa, whereas the adhesion force was 3.68 nN. AFM is a modern tool with a broad spectrum of observational and measurement abilities. Young's modulus and the adhesion force can be treated as parameters in the evaluation of intensity and changes which take place in pathogenic microorganisms under the influence of various lytic factors. The visualization of the changes in association with nanomechanical features provides a realistic portrayal of the lytic abilities of the elements of the innate and adaptive human immune system.

Impact of rearing conditions on the microbiological quality of raw retail poultry meat.

PubMed

Hardy, Bridgshe; Crilly, Nate; Pendleton, Sean; Andino, Ana; Wallis, Audra; Zhang, Nan; Hanning, Irene

2013-08-01

There is a gap in knowledge of microbiological quality in raw chicken products produced by nonconventional methods and no studies have reported the microbiological quality of turkeys produced under different rearing environments. Thus, the aim of this study was to compare the microbiological quality of conventionally and organically reared whole chicken and turkey carcasses purchased from 3 retail outlets in Knoxville, Tenn., U.S.A. A total of 100 raw broiler chickens organically (n = 50) and 50 raw turkey carcasses consisting of 3 brands reared either conventionally (n = 25) or organically (n = 25) were evaluated. The FDA BAM protocol for rinsing poultry carcasses was used to enumerate of aerobic bacteria, Campylobacter, and Staphylococcus spp., and for qualitative analysis of Salmonella. Organic chickens from one brand had the highest average counts of aerobic bacteria, Staphylococcus spp. and Campylobacter (4.8, 4.8, and 4.7 Log10 CFU/mL rinsate, respectively) while the other organic brand had the lowest average counts (3.4, 3.3, and 3.1, respectively) of all 4 brands evaluated. The organic turkeys had the highest average counts of these same bacteria (4, 3.9, and 3.8, respectively) compared to the 2 brands of conventional turkeys evaluated. Salmonella (5% prevalence) was isolated only from organic chickens and turkeys. From these data, it appears that the microbiological quality of the raw product was not dependent on rearing conditions and, thus, it cannot be assumed that organic raw poultry is safer than conventionally raised poultry in terms of microbiological quality. © 2013 Institute of Food Technologists®

Use of microbiological indicators for assessing hygiene controls for the manufacture of powdered infant formula.

PubMed

Buchanan, Robert L; Oni, Ruth

2012-05-01

Microbiological testing for various indicator microorganisms is used extensively as a means of verifying the effectiveness of efforts to ensure the microbiological quality and safety of a wide variety of foods. However, for each use of an indicator organism the underlying scientific assumptions related to the behavior of the target microorganism, the characteristics of the food matrix, the details of the food manufacturing processes, environment, and distribution system, and the methodological basis for the assay must be evaluated to determine the validity, utility, and efficacy of potential microbiological indicator tests. The recent adoption by the Codex Alimentarius Commission of microbiological criteria for powdered infant formulae and related products provides an excellent example of an evidence-based approach for the establishment of consensus microbiological criteria. The present article reviews these criteria and those of various national governments in relation to emerging principles for the evidence-based establishment of effective indicator organisms.

The value of case-based teaching vignettes in clinical microbiology rounds.

PubMed

Spicer, Jennifer O; Kraft, Colleen S; Burd, Eileen M; Armstrong, Wendy S; Guarner, Jeannette

2014-03-01

To describe the implementation and evaluation of a case-based microbiology curriculum during daily microbiology rounds. Vignettes consist of short cases with images and questions that facilitate discussion among microbiologists, pathologists, infectious disease physicians, and trainees (residents and fellows). We performed a survey to assess the value of these vignettes to trainees. Motivation to come to rounds on time increased from 60% to 100%. Trainees attending rounds after implementation of the vignettes perceived the value of microbiology rounds to be significantly higher compared with those who attended rounds before implementation (P = .04). Pathology residents found that vignettes were helpful for retaining knowledge (8.3 of 10 points). The vignettes have enhanced the value of microbiology rounds by serving as a formalized curriculum exposing trainees from multiple specialties to various microbiology topics. Emphasis on interdisciplinary interactions between clinical and laboratory personnel was highlighted with this case-based curriculum.

Evaluation of oral microbiology lab curriculum reform.

PubMed

Nie, Min; Gao, Zhen Y; Wu, Xin Y; Jiang, Chen X; Du, Jia H

2015-12-07

According to the updated concept of oral microbiology, the School of Stomatology, Wuhan University, has carried out oral microbiology teaching reforms during the last 5 years. There was no lab curriculum before 2009 except for a theory course of oral microbiology. The school has implemented an innovative curriculum with oral medicine characteristics to strengthen understanding of knowledge, cultivate students' scientific interest and develop their potential, to cultivate the comprehensive ability of students. This study was designed to evaluate the oral microbiology lab curriculum by analyzing student performance and perceptions regarding the curriculum from 2009 to 2013. The lab curriculum adopted modalities for cooperative learning. Students collected dental plaque from each other and isolated the cariogenic bacteria with selective medium plates. Then they purified the enrichment culture medium and identified the cariogenic strains by Gram stain and biochemical tests. Both quantitative and qualitative data for 5 years were analysed in this study. Part One of the current study assessed student performance in the lab from 2009 to 2013. Part Two used qualitative means to assess students' perceptions by an open questionnaire. The 271 study students' grades on oral microbiology improved during the lab curriculum: "A" grades rose from 60.5 to 81.2 %, and "C" grades fell from 28.4 to 6.3 %. All students considered the lab curriculum to be interesting and helpful. Quantitative and qualitative data converge to suggest that the lab curriculum has strengthened students' grasp of important microbiology-related theory, cultivated their scientific interest, and developed their potential and comprehensive abilities. Our student performance and perception data support the continued use of the innovative teaching system. As an extension and complement of the theory course, the oral microbiology lab curriculum appears to improve the quality of oral medicine education and help to cultivate high-quality innovative medical talents.

Semiquantitative bacterial observations with group B streptococcal vulvovaginitis.

PubMed Central

Monif, G R

1999-01-01

OBJECTIVE: Group B streptococcal (GBS) vulvovaginitis is a poorly-delineated clinical entity. The purpose of this study is to report semiquantitative data from four cases of GBS vulvovaginitis and to comment on their significance in terms of the in vitro inhibitory capabilities of GBS. METHODOLOGY: Four patients whose clinical presentations were consistent with GBS vulvovaginitis, from whom GBS was isolated and for whom semi-quantitative as well as qualitative microbiologic data existed, were identified. RESULTS: To produce vulvovaginitis, GBS must be at a high multiplicity (10(8) CFU/g of vaginal fluid). Single coisolates were identified in three of the four cases (two cases of Escherichia coli and one case of Staphylococcus aureus). Group B streptococcus does not inhibit either of these bacteria in vitro. CONCLUSION: When the growth requirements for the demonstration of in vitro inhibition for GBS or lack thereof are met in vivo, the in vivo observations are consistent with those projected from the in vitro data. PMID:10524667

Enhancing antioxidant activity, microbial and sensory quality of mango (Mangifera indica L.) juice by γ-irradiation and its in vitro radioprotective potential.

PubMed

Naresh, Kondapalli; Varakumar, Sadineni; Variyar, Prasad Shekhar; Sharma, Arun; Reddy, Obulam Vijaya Sarathi

2015-07-01

Gamma irradiation is an effective method currently being used for microbial decontamination and insect disinfestations of foods. In the present study, mango (Mangifera indica L.) juice was irradiated at doses of 0, 1.0, 3.0 and 5.0 kGy and microbial load, total polyphenols, flavonoids, ascorbic acid content, antioxidant activities, colour and sensory properties were evaluated immediately after irradiation and also during storage. Microbiological assay of the fresh and stored mango juice showed better quality after γ-irradiation. The total polyphenols and flavonoids were significantly (p < 0.05) increased while the ascorbic acid content decreased with the irradiation doses applied. As a result of γ-irradiation, a significant increment in gallic, syringic and chlorogenic acids and a significant reduction in ferulic and synapic acids were noted when analyzed by HPLC. In vitro antioxidant potentials were measured using DPPH, FRAP and NO scavenging assays; the results showed significant enhancement in the activities after irradiation, that correlated well with the increase in phenolic and flavonoid content. γ-irradiation improved the colour of mango juice without any adverse changes in the sensory qualities. Significant in vitro plasmid DNA protection was observed in the presence of mango juice against radiation induced damage, even at the dose of 5 kGy. This study confirmed the potential of γ-irradiation as a method for microbial decontamination and improving the quality of the mango juice without compromising on the sensory attributes.

Comparison of Phenotypic and Genotypic Methods for Detection of Diphtheria Toxin among Isolates of Pathogenic Corynebacteria

PubMed Central

Efstratiou, Androulla; Engler, Kathryn H.; Dawes, Charlotte S.; Sesardic, Dorothea

1998-01-01

We have compared molecular, immunochemical, and cytotoxic assays for the detection of diphtheria toxin from 55 isolates of Corynebacterium diphtheriae and Corynebacterium ulcerans originally isolated in five different countries. The suitabilities and accuracies of these assays for the laboratory diagnosis of diphtheria were compared and evaluated against the “gold standard” in vivo methods. The in vivo and Vero cell cytotoxicity assays were accurate in their abilities to detect diphtheria toxin but were time-consuming; however, the cytotoxicity assay is a suitable in vitro alternative to the in vivo virulence test. There was complete concordance between all the phenotypic methods. Genotypic tests based upon PCR were rapid; however, PCR must be used with caution because some isolates of C. diphtheriae possessed toxin genes but failed to express a biologically active toxin. Therefore, phenotypic confirmation of toxigenicity for the microbiological diagnosis of diphtheria is recommended. PMID:9774560

Comparison of phenotypic and genotypic methods for detection of diphtheria toxin among isolates of pathogenic corynebacteria.

PubMed

Efstratiou, A; Engler, K H; Dawes, C S; Sesardic, D

1998-11-01

We have compared molecular, immunochemical, and cytotoxic assays for the detection of diphtheria toxin from 55 isolates of Corynebacterium diphtheriae and Corynebacterium ulcerans originally isolated in five different countries. The suitabilities and accuracies of these assays for the laboratory diagnosis of diphtheria were compared and evaluated against the "gold standard" in vivo methods. The in vivo and Vero cell cytotoxicity assays were accurate in their abilities to detect diphtheria toxin but were time-consuming; however, the cytotoxicity assay is a suitable in vitro alternative to the in vivo virulence test. There was complete concordance between all the phenotypic methods. Genotypic tests based upon PCR were rapid; however, PCR must be used with caution because some isolates of C. diphtheriae possessed toxin genes but failed to express a biologically active toxin. Therefore, phenotypic confirmation of toxigenicity for the microbiological diagnosis of diphtheria is recommended.

Nitric oxide nanoparticles

PubMed Central

Schairer, David O.; Martinez, Luis R.; Blecher, Karin; Chouake, Jason S.; Nacharaju, Parimala; Gialanella, Philip; Friedman, Joel M.; Nosanchuk, Joshua D.; Friedman, Adam J.

2012-01-01

Nitric oxide (NO) is a critical component of host defense against invading pathogens; however, its therapeutic utility is limited due to a lack of practical delivery systems. Recently, a NO-releasing nanoparticulate platform (NO-np) was shown to have in vitro broad-spectrum antimicrobial activity and in vivo pre-clinical efficacy in a dermal abscess model. To extend these findings, both topical (TP) and intralesional (IL) NO-np administration was evaluated in a MRSA intramuscular murine abscess model and compared with vancomycin. All treatment arms accelerated abscess clearance clinically, histologically, and by microbiological assays on both days 4 and 7 following infection. However, abscesses treated with NO-np via either route demonstrated a more substantial, statistically significant decrease in bacterial survival based on colony forming unit assays and histologically revealed less inflammatory cell infiltration and preserved muscular architecture. These data suggest that the NO-np may be an effective addition to our armament for deep soft tissue infections. PMID:22286699

Improved Properties and Microbiological Safety of Novel Cottage Cheese Containing Spices

PubMed Central

Knežević, Zvonimira Medverec; Frece, Jadranka; Markov, Ksenija; Kazazić, Snježana; Mrvčić, Jasna

2015-01-01

Summary The study focuses on developing novel cottage cheese containing spices with acceptable sensory properties, increased biological value and extended shelf life. Thirty types of cheese with added fresh or dried parsley, dill, pepper, garlic and rosemary were produced. Characterisation of phenolic compounds, antioxidant capacity and antibacterial activity of spices and cheese samples were evaluated. The cheese containing fresh pepper and fresh and dried herbs showed excellent sensory properties, with the best results obtained with fresh sweet red pepper. Dry rosemary had the highest antioxidant and antibacterial activity due to high mass fractions of caffeic and rosmarinic acids as well as high mass fractions of flavones and phenolic diterpenes. The plant extracts examined in vitro and in situ effectively reduce numbers of foodborne pathogens like Salmonella typhimurium, Escherichia coli, Staphylococcus aureus and Listeria monocytogenes, and therefore have potential as natural preservatives and antioxidants. PMID:27904380

Human intravenous immunoglobulin for experimental streptococcal toxic shock: bacterial clearance and modulation of inflammation.

PubMed

Sriskandan, Shiranee; Ferguson, Melissa; Elliot, Victoria; Faulkner, Lee; Cohen, Jonathan

2006-07-01

Polyclonal human intravenous immunoglobulin (IVIG) has been advocated as an adjunct to therapy in severe invasive streptococcal toxic shock because of its ability to neutralize superantigen toxins. The aim of this study was to assess IVIG therapeutic efficacy in an experimental model of streptococcal toxic shock. To confirm the in vitro activity of IVIG against the Streptococcus pyogenes strain used in the study, IVIG was tested for superantigen neutralizing and bacterial opsonizing activity prior to in vivo studies. To evaluate the in vivo effects of IVIG in terms of microbiological outcome and disease severity in a superantigen-sensitive transgenic model of streptococcal shock, HLA-DQ transgenic mice were treated with IVIG either at the time of infection or after infection with S. pyogenes. Antibiotics were included in some studies. The IVIG preparation neutralized superantigenicity of S. pyogenes in vitro and enhanced bacterial killing in a whole blood assay. When given to mice at the time of S. pyogenes infection, IVIG neutralized circulating superantigens and reduced systemic inflammatory response. Remarkably, IVIG-enhanced systemic clearance of bacteria and enhanced neutrophil infiltrate into the infected tissues. However, when used in combination with penicillin and clindamycin in a delayed treatment setting, IVIG did not confer additional therapeutic benefit, in terms of inflammatory response, bacterial clearance or survival. IVIG monotherapy can confer benefit in experimental streptococcal shock, but extension of these findings to the clinical situation will require further evaluation.

Bioactive borate glass scaffolds: in vitro and in vivo evaluation for use as a drug delivery system in the treatment of bone infection.

PubMed

Liu, Xin; Xie, Zongping; Zhang, Changqing; Pan, Haobo; Rahaman, Mohamed N; Zhang, Xin; Fu, Qiang; Huang, Wenhai

2010-02-01

The objective of this work was to evaluate borate bioactive glass scaffolds (with a composition in the system Na(2)O-K(2)O-MgO-CaO-B(2)O(3)-P(2)O(5)) as devices for the release of the drug Vancomycin in the treatment of bone infection. A solution of ammonium phosphate, with or without dissolved Vancomycin, was used to bond borate glass particles into the shape of pellets. The in vitro degradation of the pellets and their conversion to a hydroxyapatite-type material in a simulated body fluid (SBF) were investigated using weight loss measurements, chemical analysis, X-ray diffraction, and scanning electron microscopy. The results showed that greater than 90% of the glass in the scaffolds degraded within 1 week, to form poorly crystallized hydroxyapatite (HA). Pellets loaded with Vancomycin provided controlled release of the drug over 4 days. Vancomycin-loaded scaffolds were implanted into the right tibiae of rabbits infected with osteomyelitis. The efficacy of the treatment was assessed using microbiological examination and histology. The HA formed in the scaffolds in vivo, resulting from the conversion of the glass, served as structure to support the growth of new bone and blood vessels. The results in this work indicate that bioactive borate glass could provide a promising biodegradable and bioactive material for use as both a drug delivery system and a scaffold for bone repair.

Clofazimine Inhibits the Growth of Babesia and Theileria Parasites In Vitro and In Vivo.

PubMed

Tuvshintulga, Bumduuren; AbouLaila, Mahmoud; Davaasuren, Batdorj; Ishiyama, Aki; Sivakumar, Thillaiampalam; Yokoyama, Naoaki; Iwatsuki, Masato; Otoguro, Kazuhiko; Ōmura, Satoshi; Igarashi, Ikuo

2016-05-01

The present study evaluated the growth-inhibitory effects of clofazimine, currently used for treating leprosy, against Babesia bovis, B. bigemina, B. caballi, and Theileria equi in in vitro culture and against Babesia microti in mice. The 50% inhibitory concentrations (IC50s) of clofazimine against the in vitro growth of B. bovis, B. bigemina, B. caballi, and T. equi were 4.5, 3, 4.3, and 0.29 μM, respectively. In mice infected with B. microti, treatment with 20 mg/kg of body weight of clofazimine administered orally resulted in a significantly lower peak parasitemia (5.3%) than that in the control group (45.9%), which was comparable to the subcutaneous administration of 25 mg/kg diminazene aceturate, the most widely used treatment for animal piroplasmosis. Although slight anemia was observed in both clofazimine- and diminazene aceturate-treated infected mice, the level and duration of anemia were lower and shorter, respectively, than those in untreated infected mice. Using blood transfusions and PCR, we also examined whether clofazimine completely killed B. microti On day 40 postinfection, when blood analysis was performed, parasites were not found in blood smears; however, the DNA of B. microti was detected in the blood of clofazimine-treated animals and in several tissues of clofazimine- and diminazene aceturate-treated mice by PCR. The growth of parasites was observed in mice after blood transfusions from clofazimine-treated mice. In conclusion, clofazimine showed excellent inhibitory effects against Babesia and Theileria in vitro and in vivo, and further study on clofazimine is required for the future development of a novel chemotherapy with high efficacy and safety against animal piroplasmosis and, possibly, human babesiosis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

In vitro comparison of acyclovir, ganciclovir and cidofovir against equid alphaherpesvirus 3 and evaluation of their efficacy against six field isolates.

PubMed

Vissani, María A; Zabal, Osvaldo; Tordoya, María S; Parreño, Viviana; Thiry, Etienne; Barrandeguy, María

2018-05-17

Equid alphaherpesvirus 3 (EHV3) is the etiological agent of equine coital exanthema (ECE), which is a venereal, highly contagious disease, characterized by the formation of papules, vesicles, pustules and ulcers on the external genitalia of mares and stallions. EHV3 remains in a latent state after a successful infection and there are latently infected animals in which the virus is reactivated and generally re-excreted subclinically. There are no available vaccines for this condition and prevention is based on the clinical examination of mares prior to mating, which allows to segregate those showing clinical signs. As this approach does not eliminate the risk of contagion in stallions from subclinically infected mares, there is a need for a specific EHV3 treatment. Nowadays, there exist various antiviral compounds of proven effectiveness for other alphaherpesviruses affecting humans and animals. The aim of the present study was to compare the efficacy of three antiviral compounds, acyclovir, ganciclovir and cidofovir against EHV3 in vitro, and to assess their efficacy against six EHV3 Argentinian field isolates. To determine the efficacy of these compounds in vitro, three parameters were analyzed: reduction of plaque number, reduction of plaque size and reduction of viral production. Additionally, the effectiveness of the three compounds at an optimum concentration previously determined in this study was investigated for the EHV3 field isolates. Based on our results, ganciclovir was the most potent antiviral compound to reduce EHV3 replication in vitro and may thus be a valuable candidate for treatment and prevention of ECE in mares and stallions. Copyright © 2018 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Antimicrobial efficacy of granulysin-derived synthetic peptides in acne vulgaris.

PubMed

Lim, Hee-Sun; Chun, Seung-Min; Soung, Min-Gyu; Kim, Jenny; Kim, Seong-Jin

2015-07-01

Antimicrobial peptides are considered as a potential alternative to antibiotic treatment in acne vulgaris because the development of a resistant strain of Propionibacterium acnes is problematic. Granulysin can be regarded as an ideal substance with which to treat acne because it has antimicrobial and anti-inflammatory effects. This study was performed to explore the effectiveness of granulysin-derived peptides (GDPs) in killing P. acnes in vitro under a standard microbiologic assay and to evaluate their potential use in a topical agent for the treatment of acne vulgaris. Twenty different peptides based on the known sequence of a GDP were synthesized and tested in vitro for antimicrobial activity. Thirty patients with facial acne vulgaris were instructed to apply a topical formulation containing synthetic GDP to acne lesions twice per day for 12 weeks. A newly synthesized peptide in which aspartic acid was substituted with arginine, and methionine was substituted with cysteine, showed the highest antimicrobial activity against P. acnes. Moreover, it was effective against both Gram-positive and Gram-negative bacteria in vitro. After treatment with the topical formulation containing 50 ppm of synthetic peptide for 12 weeks, a significant reduction in the number of pustules was observed, regardless of the increase in the number of comedones. In addition, a significant reduction in the clinical grade of acne based on the Korean Acne Grading System (KAGS) was evident. Synthesized GDP shows strong antimicrobial activity against P. acnes in vitro. The clinical improvement observed suggests a topical formulation containing the GDP has therapeutic potential for the improvement of inflammatory-type acne vulgaris by its antimicrobial activity. © 2015 The International Society of Dermatology.

In Vitro Activity of Ceftaroline against Staphylococcus aureus Isolates Collected in 2012 from Latin American Countries as Part of the AWARE Surveillance Program.

PubMed

Biedenbach, Douglas J; Hoban, Daryl J; Reiszner, Edina; Lahiri, Sushmita D; Alm, Richard A; Sahm, Daniel F; Bouchillon, Samuel K; Ambler, Jane E

2015-12-01

The in vitro activities of ceftaroline and comparators, using broth microdilution, were determined against 1,066 Staphylococcus aureus isolates from hospitalized patients. Seventeen medical centers from Latin American countries contributed isolates. Methicillin-resistant S. aureus (MRSA) percentages ranged from 46% (Brazil) to 62% (Argentina). All methicillin-susceptible S. aureus (MSSA) isolates were susceptible to ceftaroline. Ceftaroline activity against MRSA varied with MIC90s of 0.5 (Venezuela) to 2 (Brazil, Chile, and Colombia) μg/ml, which was the highest MIC value. ST-5 was the most common sequence type. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

In vitro and intracellular activities of peptide deformylase inhibitor GSK1322322 against Legionella pneumophila isolates.

PubMed

Dubois, Jacques; Dubois, Maïtée; Martel, Jean-François; Aubart, Kelly; Butler, Deborah

2015-01-01

GSK1322322, a novel peptide deformylase inhibitor currently in development as an oral and intravenous agent for the treatment of hospitalized community-acquired bacterial pneumonia, showed poor in vitro activity against a panel of 50 Legionella pneumophila strains, with MICs ranging from 1 to 16 μg/ml and an MIC90 of 16 μg/ml, but very potent intracellular activity, with the minimum extracellular concentrations capable of inhibiting intracellular proliferation (MIECs) ranging from 0.12 to 2 μg/ml and 98% of the strains being inhibited by concentrations of ≤ 1 μg/ml. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

[Spontaneous bacterial peritonitis: impact of microbiological changes].

PubMed

Almeida, Paulo Roberto Lerias de; Camargo, Nutianne Schneider; Arenz, Maximilhano; Tovo, Cristiane Valle; Galperim, Bruno; Behar, Paulo

2007-01-01

Spontaneous bacterial peritonitis is a serious complication in cirrhotic patients, and the changes in the microbiological characteristics reported in the last years are impacting the choice of antibiotic used in the treatment. To evaluate the change in the epidemiology and antibiotic resistance of the bacteria causing spontaneous bacterial peritonitis in a 7 years period. All the cases of cirrhotic patients with spontaneous bacterial peritonitis with positive cultural examination were retrospectively studied. Two periods were evaluated: 1997-1998 and 2002-2003. The most frequent infecting organisms and the sensitivity in vitro to antibiotics were registered. In the first period (1997-1998) there were 33 cases, 3 (9%) with polymicrobial infection. The most common were: E.coli in 13 (36,11%), Staphylococcus coagulase-negative in 6 (16,66%), K. pneumoniae in 5 (13,88%), S. aureus in 4 (11,11%) and S. faecalis in 3 (8,33%). In 2003-2004, there were 43 cases, 2 (5%) with polymicrobial infection. The most frequent were: Staphylococus coagulase-negative in 16 (35,55%), S. aureus in 8 (17,77%), E. coli in 7 (15,55%) and K. pneumoniae in 3 (6,66%). No one was using antibiotic prophilaxys. The prevalence of S. aureus methicillin-resitant to quinolone and trimethoprim-sulfamethoxazole changed from 25% to 50%, and vancomicin was the only one with absolute activity during all the period. In the same way, the prevalence of E. coli resistant to third generation cephalosporin and to quinolone changed from 0% to 16%. There was a modification of the bacterial population causing spontaneous bacterial peritonitis, with high frequency of gram-positive organisms, as well as an increase in the resistance to the traditionally recommended antibiotics. This study suggests a probable imminent inclusion of a drug against gram-positive organisms in the empiric treatment of spontaneous bacterial peritonitis.

A prospective study of treatment of carbapenem-resistant Enterobacteriaceae infections and risk factors associated with outcome.

PubMed

de Maio Carrilho, Claudia M D; de Oliveira, Larissa Marques; Gaudereto, Juliana; Perozin, Jamile S; Urbano, Mariana Ragassi; Camargo, Carlos H; Grion, Cintia M C; Levin, Anna Sara S; Costa, Silvia F

2016-11-03

To describe the clinical and microbiological data of carbapenem-resistant Enterobacteriaceae (CRE) infections, the treatment used, hospital- and infection-related mortality, and risk factors for death. A prospective cohort conducted from March 2011 to December 2012. Clinical, demographic, and microbiological data such as in vitro sensitivity, clonality, carbapenemase gene mortality related to infection, and overall mortality were evaluated. Data were analyzed using Epi Info version 7.0 (CDC, Atlanta, GA, USA) and SPSS (Chicago, IL, USA). One hundred and twenty-seven patients were evaluated. Pneumonia, 52 (42 %), and urinary tract infections (UTI), 51 (40.2 %), were the most frequent sites of infection. The isolates were polyclonal; the Bla KPC gene was found in 75.6 % of isolates, and 27 % of isolates were resistant to colistin. Mortality related to infection was 34.6 %, and was higher among patients with pneumonia (61.4 %). Combination therapy was used in 98 (77.2 %), and monotherapy in 22.8 %; 96.5 % of them were UTI patients. Shock, age, and dialysis were independent risk factors for death. There was no difference in infection-related death comparing colistin-susceptible and colistin-resistant infections (p = 0.46); neither in survival rate comparing the use of combination therapy with two drugs or more than two drugs (p = 0.32). CRE infection mortality was higher among patients with pneumonia. Infections caused by colistin-resistant isolates did not increase mortality. The use of more than two drugs on combination therapy did not show a protective effect on outcome. The isolates were polyclonal, and the bla KPC gene was the only carbapenemase found. Shock, dialysis, and age over 60 years were independent risk factors for death.

Evaluation of the operator protection factors offered by positive pressure air suits against airborne microbiological challenge.

PubMed

Steward, Jackie A; Lever, Mark S

2012-08-01

Laboratories throughout the world that perform work with Risk Group 4 Pathogens generally adopt one of two approaches within BSL-4 environments: either the use of positive pressure air-fed suits or using Class III microbiological safety cabinets and isolators for animal work. Within the UK at present, all laboratories working with Risk Group 4 agents adopt the use of Class III microbiological safety cabinet lines and isolators. Operator protection factors for the use of microbiological safety cabinets and isolators are available however; there is limited published data on the operator protection factors afforded by the use of positive pressure suits. This study evaluated the operator protection factors provided by positive pressure air suits against a realistic airborne microbiological challenge. The suits were tested, both intact and with their integrity compromised, on an animated mannequin within a stainless steel exposure chamber. The suits gave operator protection in all tests with an intact suit and with a cut in the leg. When compromised by a cut in the glove, a very small ingress of the challenge was seen as far as the wrist. This is likely to be due to the low airflow in the gloves of the suit. In all cases no microbiological penetration of the respiratory tract was observed. These data provide evidence on which to base safety protocols for use of positive pressure suits within high containment laboratories.

Testing the performance of microbiological safety cabinets used in microbiology laboratories in South Korea.

PubMed

Hwang, S H; Yi, T W; Cho, K H; Lee, I M; Yoon, C S

2011-09-01

To test a performance of the microbiological safety cabinets (MSCs) according to the type of MSCs in microbial laboratories. Tests were carried out to assess the performance of 31 MSCs in 14 different facilities, including six different biological test laboratories in six hospitals and eight different laboratories in three universities. The following tests were performed on the MSCs: the downflow test, intake velocity test, high-efficiency particulate air filter leak test and the airflow smoke pattern test. These performance tests were carried out in accordance with the standard procedures. Only 23% of Class II A1 (8), A2 (19) and unknown MSCs (4) passed these performance tests. The main reasons for the failure of MSCs were inappropriate intake velocity (65%), leakage in the HEPA filter sealing (50%), unbalanced airflow smoke pattern in the cabinets (39%) and inappropriate downflow (27%). This study showed that routine checks of MSCs are important to detect and strengthen the weak spots that frequently develop, as observed during the evaluation of the MSCs of various institutions. Routine evaluation and maintenance of MSCs are critical for optimizing performance. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

Commutability of food microbiology proficiency testing samples.

PubMed

Abdelmassih, M; Polet, M; Goffaux, M-J; Planchon, V; Dierick, K; Mahillon, J

2014-03-01

Food microbiology proficiency testing (PT) is a useful tool to assess the analytical performances among laboratories. PT items should be close to routine samples to accurately evaluate the acceptability of the methods. However, most PT providers distribute exclusively artificial samples such as reference materials or irradiated foods. This raises the issue of the suitability of these samples because the equivalence-or 'commutability'-between results obtained on artificial vs. authentic food samples has not been demonstrated. In the clinical field, the use of noncommutable PT samples has led to erroneous evaluation of the performances when different analytical methods were used. This study aimed to provide a first assessment of the commutability of samples distributed in food microbiology PT. REQUASUD and IPH organized 13 food microbiology PTs including 10-28 participants. Three types of PT items were used: genuine food samples, sterile food samples and reference materials. The commutability of the artificial samples (reference material or sterile samples) was assessed by plotting the distribution of the results on natural and artificial PT samples. This comparison highlighted matrix-correlated issues when nonfood matrices, such as reference materials, were used. Artificially inoculated food samples, on the other hand, raised only isolated commutability issues. In the organization of a PT-scheme, authentic or artificially inoculated food samples are necessary to accurately evaluate the analytical performances. Reference materials, used as PT items because of their convenience, may present commutability issues leading to inaccurate penalizing conclusions for methods that would have provided accurate results on food samples. For the first time, the commutability of food microbiology PT samples was investigated. The nature of the samples provided by the organizer turned out to be an important factor because matrix effects can impact on the analytical results. © 2013 The Society for Applied Microbiology.

Selection and evaluation of micro-organisms for biocontrol of Verticillium dahliae in olive.

PubMed

Varo, A; Raya-Ortega, M C; Trapero, A

2016-09-01

To identify potential biological control agents against Verticillium wilt in olive through a mass screening approach. A total of 47 strains and nine mixtures of micro-organisms were evaluated against Verticillium dahliae in a three stage screening: (i) in vitro, by the effect on the mycelial growth and spore germination of the pathogen; (ii) in natural infested soil, by the effect on the reduction of microsclerotia of the pathogen; (iii) in planta, by the effect on the infection of olive plants under controlled conditions. Various fungal and bacterial strains and mixtures inhibited the pathogen and showed consistent biocontrol activity against Verticillium wilt of olive. The screening has resulted in promising fungi and bacteria strains with antagonistic activity against Verticillium, such as two non-pathogenic Fusarium oxysporum, one Phoma sp., one Pseudomonas fluorescens and two mixtures of micro-organisms that may possess multiple modes of action. This study provides a practical basis for the potential use of selected strains as biocontrol agents for the protection of olive plants against V. dahliae infection. In addition, our study presented an effective method to evaluate antagonistic micro-organisms of V. dahliae in olive. © 2016 The Society for Applied Microbiology.

Gentamicin-loaded borate bioactive glass eradicates osteomyelitis due to Escherichia coli in a rabbit model.

PubMed

Xie, Zongping; Cui, Xu; Zhao, Cunju; Huang, Wenhai; Wang, Jianqiang; Zhang, Changqing

2013-07-01

The treatment of osteomyelitis induced by Gram-negative bacilli is rarely reported in the literature. This study established a rabbit tibia model of osteomyelitis induced by the Gram-negative bacillus Escherichia coli. Using this model, pellets composed of a chitosan-bonded mixture of borate bioactive glass and gentamicin were evaluated in vitro and in vivo for the treatment of osteomyelitis induced by Escherichia coli. Our results showed that the pellets in phosphate-buffered saline released gentamicin continuously over 26 days. Without the simultaneous use of a systemic antibiotic, the implantation of the gentamicin-loaded pellets into the osteomyelitis region of the tibia resulted in the eradication of 81.82% of infections, as determined by microbiological, histological and radiographic evaluation, and supported the ingrowth of new bone into the tibia defects after 6 weeks of implantation. The results indicate that the gentamicin-loaded borate bioactive glass implant, combining sustained drug release with the ability to support new bone formation, could provide a method for treating osteomyelitis induced by Gram-negative bacilli.

Gentamicin-Loaded Borate Bioactive Glass Eradicates Osteomyelitis Due to Escherichia coli in a Rabbit Model

PubMed Central

Xie, Zongping; Cui, Xu; Zhao, Cunju; Huang, Wenhai; Wang, Jianqiang

2013-01-01

The treatment of osteomyelitis induced by Gram-negative bacilli is rarely reported in the literature. This study established a rabbit tibia model of osteomyelitis induced by the Gram-negative bacillus Escherichia coli. Using this model, pellets composed of a chitosan-bonded mixture of borate bioactive glass and gentamicin were evaluated in vitro and in vivo for the treatment of osteomyelitis induced by Escherichia coli. Our results showed that the pellets in phosphate-buffered saline released gentamicin continuously over 26 days. Without the simultaneous use of a systemic antibiotic, the implantation of the gentamicin-loaded pellets into the osteomyelitis region of the tibia resulted in the eradication of 81.82% of infections, as determined by microbiological, histological and radiographic evaluation, and supported the ingrowth of new bone into the tibia defects after 6 weeks of implantation. The results indicate that the gentamicin-loaded borate bioactive glass implant, combining sustained drug release with the ability to support new bone formation, could provide a method for treating osteomyelitis induced by Gram-negative bacilli. PMID:23629702

Treatment modalities and evaluation models for periodontitis

PubMed Central

Tariq, Mohammad; Iqbal, Zeenat; Ali, Javed; Baboota, Sanjula; Talegaonkar, Sushama; Ahmad, Zulfiqar; Sahni, Jasjeet K

2012-01-01

Periodontitis is the most common localized dental inflammatory disease related with several pathological conditions like inflammation of gums (gingivitis), degeneration of periodontal ligament, dental cementum and alveolar bone loss. In this perspective, the various preventive and treatment modalities, including oral hygiene, gingival irrigations, mechanical instrumentation, full mouth disinfection, host modulation and antimicrobial therapy, which are used either as adjunctive treatments or as stand-alone therapies in the non-surgical management of periodontal infections, have been discussed. Intra-pocket, sustained release systems have emerged as a novel paradigm for the future research. In this article, special consideration is given to different locally delivered anti-microbial and anti inflammatory medications which are either commercially available or are currently under consideration for Food and Drug Administration (FDA) approval. The various in vitro dissolution models and microbiological strain investigated to impersonate the infected and inflamed periodontal cavity and to predict the in vivo performance of treatment modalities have also been thrashed out. Animal models that have been employed to explore the pathology at the different stages of periodontitis and to evaluate its treatment modalities are enlightened in this proposed review. PMID:23373002

Clinical and microbiologic effects of commercially available dentifrice containing aloe vera: a randomized controlled clinical trial.

PubMed

Pradeep, A R; Agarwal, Esha; Naik, Savitha B

2012-06-01

Certain plants used in folk medicine serve as a source of therapeutic agents that have antimicrobial and other multipotential effects. This prospective, randomized, placebo, and positively controlled clinical trial was designed to evaluate the clinical and microbiologic effects of a commercially available dentifrice containing aloe vera on the reduction of plaque and gingival inflammation in patients with gingivitis. Ninety patients diagnosed with chronic generalized gingivitis were selected and randomly divided into three groups: group 1, placebo toothpaste; group 2, toothpaste containing aloe vera; and group 3, toothpaste with polymer and fluoride containing triclosan. Clinical evaluation was undertaken using a gingival index, plaque was assessed using a modification of the Quigley-Hein index, and microbiologic counts were assessed at baseline, 6 weeks, 12 weeks, and 24 weeks. A subjective evaluation was also undertaken by questionnaire. Toothpaste containing aloe vera showed significant improvement in gingival and plaque index scores as well as microbiologic counts compared with placebo dentifrice. These improvements were comparable to those achieved with toothpaste containing triclosan. Toothpaste containing aloe vera may be a useful herbal formulation for chemical plaque control agents and improvement in plaque and gingival status.

Microbiological concerns and methodological approaches related to bacterial water quality in spaceflight

NASA Technical Reports Server (NTRS)

Pyle, Barry H.; Mcfeters, Gordon A.

1992-01-01

A number of microbiological issues are of critical importance to crew health and system performance in spacecraft water systems. This presentation reviews an army of these concerns which include factors that influence water treatment and disinfection in spaceflight such as biofilm formation and the physiological responses of bacteria in clean water systems. Factors associated with spaceflight like aerosol formation under conditions of microgravity are also discussed within the context of airborne infections such as Legionellosis. Finally, a spectrum of analytical approaches is reviewed to provide an evaluation of methodological alternatives that have been suggested or used to detect microorganisms of interest in water systems. These range from classical approaches employing colony formation on specific microbiological growth media to direct (i.e. microscopic) and indirect (e.g. electrochemical) methods as well as the use of molecular approaches and gene probes. These techniques are critically evaluated for their potential utility in determining microbiological water quality through the detection of microorganisms under the influence of ambient environmental stress inherent in spaceflight water systems.

Irradiated vacuum-packed lamb meat stored under refrigeration: microbiology, physicochemical stability and sensory acceptance.

PubMed

Fregonesi, R P; Portes, R G; Aguiar, A M M; Figueira, L C; Gonçalves, C B; Arthur, V; Lima, C G; Fernandes, A M; Trindade, M A

2014-06-01

Reducing spoilage and indicator bacteria is important for microbiological stability in meat and meat products. The objective was to evaluate the effect of different doses of gamma radiation on the shelf-life of lamb meat, vacuum-packed and stored under refrigeration, by assessing the microbiological safety, physicochemical stability and sensory quality. Lamb loin cuts (Longissimus dorsi) were irradiated with 1.5kGy and 3.0kGy. The samples, including control, were stored at 1±1°C during 56days. Samples were analyzed on zero, 14, 28, 42 and 56days by their microbiological and physicochemical characteristics. Sensory quality was carried out on day zero. The results showed a reduction (p<0.05) in the microbial load of the irradiated samples. The acceptance of lamb loins was not affected (p>0.05) by the radiation doses. Thus gamma irradiation at 3.0kGy was effective in reducing the content of microorganisms, without harming the physicochemical characteristics evaluated. Copyright © 2014 Elsevier Ltd. All rights reserved.

Microbiological Evaluation of Containment Isolators for the Care of Patients with Exotic Diseases.

DTIC Science & Technology

1980-02-01

The microbiological integrity of containment isolators obtained from Vickers Limited Medical Engineering was evaluated using aerosols of Tl coliphage ...diluted in sterile distilled water (SDW). Aliquots for plate counts were mixed with log phase host cells and the mixture spread evenly on pre-dried...of water was diffi- cult to maintain and measure accurately even with sensitive meters, and finally visual observation of the curvature of the side

Evaluation of the Feasibility of Biodegrading Explosives-Contaminated Soils and Groundwater at the Newport Army Ammunition Plant (NAAP)

DTIC Science & Technology

1991-06-01

undamaged to its original location. 9 3 Biodegradation Studies The NAAP soils were used for both the basic microbiological studies and the bench scale...reactor studies. The microbiological studies were directed at measuring (1) the growth potential of bacteria present in the soil samples and (2) the...clear and odorless, and no TNT was detected in them. The detection limit for TNT in the water samples was 0.5 mg/L. Microbiological characterization

A transient expression assay for the in planta efficacy screening of an antimicrobial peptide against grapevine bacterial pathogens.

PubMed

Visser, M; Stephan, D; Jaynes, J M; Burger, J T

2012-06-01

Natural and synthetic antimicrobial peptides (AMPs) are of increasing interest as potential resistance conferring elements in plants against pathogen infection. The efficacy of AMPs against pathogens is prescreened by in vitro assays, and promising AMP candidates are introduced as transgenes into plants. As in vitro and in planta environments differ, a prescreening procedure of the AMP efficacy in the plant environment is desired. Here, we report the efficacy of the purified synthetic peptide D4E1 against the grapevine-infecting bacterial pathogens Agrobacterium vitis and Xylophilus ampelinus in vitro and describe for the first time an in planta prescreening procedure based on transiently expressed D4E1. The antimicrobial effect of D4E1 against Ag. vitis and X. ampelinus was shown by a reduction in colony-forming units in vitro in a traditional plate-based assay and by a reduction in bacterial titres in planta as measured by quantitative real-time PCR (qPCR) in grapevine leaves transiently expressing D4E1. A statistically significant reduction in titre was shown for X. ampelinus, but for Ag. vitis, a significant reduction in titre was only observed in a subset of plants. The titres of both grapevine-infecting bacterial pathogens were reduced in an in vitro assay and for X. ampelinus in an in planta assay by D4E1 application. This widens the applicability of D4E1 as a potential resistance-enhancing element to additional pathogens and in a novel plant species. D4E1 is a promising candidate to confer enhanced resistance against the two tested grapevine bacterial pathogens, and the applied transient expression system proved to be a valuable tool for prescreening of D4E1 efficacy in an in planta environment. The described prescreening procedure can be used for other AMPs and might be adapted to other plant species and pathogens before the expensive and tedious development of stably transgenic lines is started. © 2012 The Authors. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

Infections in the tissue material and their impact on the loss of transplants in the Laboratory of in vitro Cell and Tissue Culture with Tissue Bank in the years 2011-2015.

PubMed

Kitala, D; Klama-Baryła, A; Kawecki, M; Kraut, M; Łabuś, W; Glik, J; Ples, M; Tomanek, E; Nowak, M

2017-03-01

Radiation sterilization eliminates microbiological infections but causes the degradation of the cell factor. The negative result of microbiological examination for tissue transplants is one of the conditions for approval for distribution in patients. The study attempts to verify impact of the presence of microbes onto material for transplant loss. In the 2011-2015 period, we analyzed 293 donors of skin and amnion. Microbiological sampling was performed. The total of 21 strains of bacteria, molds and fungi was identified in collected tissue. The widest spectrum of strains was found in skin (17), followed by amnia (8). The total number of positive findings was 147 and was again highest in skin (129), while the number of positive findings in amnia was 18 only. The general percentage of fungal infections was very low. The presence of fungal strains was only observed in allogeneic skin (2%). Large number of microorganisms isolated from the skin before sterilization was observed, so it seems impossible to use allogeneic intravital skin. However, the intravital application of allogeneic amnion obtained from cesarean section remains to be considered.

The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum.

PubMed

Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

2013-12-01

The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. © 2013 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Application of lemongrass oil in vapour phase for the effective control of anthracnose of 'Sekaki' papaya.

PubMed

Ali, A; Wee Pheng, T; Mustafa, M A

2015-06-01

To evaluate the potential use of lemongrass essential oil vapour as an alternative for synthetic fungicides in controlling anthracnose of papaya. Lemongrass oil used in the study was characterized using gas chromatography-flame ionization detection (GC-FID) before it was tested against anthracnose of papaya in vitro and in vivo. The GC-FID analysis showed that geranial (45·6%) and neral (34·3%) were the major components in lemongrass oil. In vitro study revealed that lemongrass oil vapour at all concentrations tested (33, 66, 132, 264 and 528 μl l(-1) ) suppressed the mycelial growth and conidial germination of Colletotrichum gloeosporioides. For the in vivo study, 'Sekaki' papaya were exposed to lemongrass oil fumigation (0, 7, 14, 28 μl l(-1) ) for 18 h and at room temperature for 9 days. Lemongrass oil vapour at the concentration of 28 μl l(-1) was most effective against anthracnose of artificially inoculated papaya fruit while quality parameters of papaya were not significantly altered. This suggests that lemongrass oil vapour can control anthracnose disease development on papaya without affecting its natural ripening process. The potential practical application of this technology can reduce reliance on synthetic fungicides for the control of postharvest diseases in papaya. © 2015 The Society for Applied Microbiology.

[Determination of physicochemical characteristics and evaluation of decontaminating efficacy and in vitro safety of cleaning products for contact lenses].

PubMed

Simon, M; Coiffard, L J; Rivalland, P; De Roeck-Holtzhauer, Y

1996-01-01

This work aims to characterize products designed for cleaning contact lenses and particularly their physicochemical properties, their efficiency and their ocular irritancy potential compared to the main requirements of eye-washes. The physicochemical controls include pH determination, viscosity and freezing point depression. In addition, we carried out the hydrogen peroxide assay for products containing this active substance. A microbiological control was performed when opening the product and after simulation of a 21-day aging. We determined the decontaminating efficacy of the products on four bacterial strains and a fungal strain. Finally, we tested their ocular allowance by an in vitro test. The pH values obtained ranged from 3.2 (oxygenated water solutions) to 7.6. The viscosity was close to a water solution one (about 1 centipoise). The different assays showed hydrogen peroxide content similar to that stated on the package: rate averaged to 3% and was negligible after neutralization. At opening and after simulation the bacteriological quality was excellent. Finally, decontaminating efficiency against germs was very good for the products tested. The products were classified as non-irritant by the ocular irritancy test. The results obtained show that the products tested met the reference criteria, particularly eye-wash criteria.

In vitro effect of a corrosive hostile ocular surface on candidate biomaterials for keratoprosthesis skirt

PubMed Central

Tan, Xiao Wei; Riau, Andri; Shi, Zhi Long; Tan, Anna C S; Neoh, Koon Gee; Khor, Khiam Aik; Beuerman, Roger W; Tan, Donald; Mehta, Jodhbir S

2012-01-01

Aim Keratoprosthesis (KPro) devices are prone to long-term corrosion and microbiological assault. The authors aimed to compare the inflammatory response and material dissolution properties of two candidate KPro skirt materials, hydroxyapatite (HA) and titania (TiO2) in a simulated in vitro cornea inflammation environment. Methods Lipopolysaccharide-stimulated cytokine secretions were evaluated with human corneal fibroblasts on both HA and TiO2. Material specimens were subjected to electrochemical and long-term incubation test with artificial tear fluid (ATF) of various acidities. Topography and surface roughness of material discs were analysed by scanning electron microscopy and atomic force microscopy. Results There were less cytokines secreted from human corneal fibroblasts seeded on TiO2 substrates as compared with HA. TiO2 was more resistant to the corrosion effect caused by acidic ATF in contrast to HA. Moreover, the elemental composition of TiO2 was more stable than HA after long-term incubation with ATF. Conclusions TiO2 is more resistant to inflammatory degradation and has a higher corrosion resistance as compared with HA, and in this regard may be a suitable material to replace HA as an osteo-odonto-keratoprosthesis skirt. This would reduce resorption rates for KPro surgery. PMID:22802307

Attaching the NorA Efflux Pump Inhibitor INF55 to Methylene Blue Enhances Antimicrobial Photodynamic Inactivation of Methicillin-Resistant Staphylococcus aureus in Vitro and in Vivo.

PubMed

Rineh, Ardeshir; Dolla, Naveen K; Ball, Anthony R; Magana, Maria; Bremner, John B; Hamblin, Michael R; Tegos, George P; Kelso, Michael J

2017-10-13

Antimicrobial photodynamic inactivation (aPDI) uses photosensitizers (PSs) and harmless visible light to generate reactive oxygen species (ROS) and kill microbes. Multidrug efflux systems can moderate the phototoxic effects of PSs by expelling the compounds from cells. We hypothesized that increasing intracellular concentrations of PSs by inhibiting efflux with a covalently attached efflux pump inhibitor (EPI) would enhance bacterial cell phototoxicity and reduce exposure of neighboring host cells to damaging ROS. In this study, we tested the hypothesis by linking NorA EPIs to methylene blue (MB) and examining the photoantimicrobial activity of the EPI-MB hybrids against the human pathogen methicillin-resistant Staphylococcus aureus (MRSA). Photochemical/photophysical and in vitro microbiological evaluation of 16 hybrids carrying four different NorA EPIs attached to MB via four linker types identified INF55-(Ac)en-MB 12 as a lead. Compound 12 showed increased uptake into S. aureus cells and enhanced aPDI activity and wound healing effects (relative to MB) in a murine model of an abrasion wound infected by MRSA. The study supports a new approach for treating localized multidrug-resistant MRSA infections and paves the way for wider exploration of the EPI-PS hybrid strategy in aPDI.

Evaluation of Telavancin Alone and Combined with Ceftaroline or Rifampin against Methicillin-Resistant Staphylococcus aureus (MRSA) in an in vitro Biofilm Model.

PubMed

Jahanbakhsh, Seyedehameneh; Singh, Nivedita B; Yim, Juwon; Rose, Warren E; Rybak, Michael J

2018-05-21

Biofilm-producing methicillin-resistant Staphylococcus aureus (MRSA) infections are challenging due to increasing antibiotic resistance. Synergistic activity of lipopeptides and lipoglycopeptides with β-lactams has been demonstrated for MRSA, but little is known about biofilm-embedded organisms. Our objective was to evaluate two telavancin (TLV) dosage regimens (7.5 mg/kg and 10 mg/kg q 24h)alone and in combination with ceftaroline (CPT) (600 mg q 8 h) or rifampin (RIF) (450 mg q 12h) against two biofilm-producing MRSA (494 and N315). Pharmacokinetic/pharmacodynamic CDC biofilm reactor models with polyurethane coupons were used to evaluate the efficacy of the antibiotic combinations over 72h. Overall, there were no significant differences observed between the two TLV dosing regimens either alone or in combination with RIF or CPT against these strains. Both TLV dosing regimens or CPT alone demonstrated killing but did not reach bactericidal reduction at 72h. However, both TLV regimens in combination with RIF demonstrated enhanced activity against both strains with a rapid decrease in CFU/ml at 4h that was bactericidal and maintained over the 72h experiment (-Δ 3.75 log10CFU/ml from baseline; P <0.0001). Of interest, no enhanced activity was observed for TLV combined with CPT. No development of resistance was observed in any of the combination models. However, resistance to RIF developed as early as 24h with MIC values exceeding 32 mg/L. Our results show that TLV plus RIF displayed therapeutic improvement against biofilm-producing MRSA. These results suggest that the TLV 7.5 and 10mg/kg q24h are equally effective in eradicating biofilm-associated MRSA in vitro . Copyright © 2018 American Society for Microbiology.

E. coli transport from bottom sediments to the stream water column in base flow conditions

USDA-ARS?s Scientific Manuscript database

E. coli as an indicator bacterium is commonly used to characterize microbiological water quality, to evaluate surface water sources for microbiological impairment, and to assess management practices that lead to the decrease of pathogens and indicator influx in surface water sources for recreation a...

Applications of Flow Cytometry to Clinical Microbiology†

PubMed Central

Álvarez-Barrientos, Alberto; Arroyo, Javier; Cantón, Rafael; Nombela, César; Sánchez-Pérez, Miguel

2000-01-01

Classical microbiology techniques are relatively slow in comparison to other analytical techniques, in many cases due to the need to culture the microorganisms. Furthermore, classical approaches are difficult with unculturable microorganisms. More recently, the emergence of molecular biology techniques, particularly those on antibodies and nucleic acid probes combined with amplification techniques, has provided speediness and specificity to microbiological diagnosis. Flow cytometry (FCM) allows single- or multiple-microbe detection in clinical samples in an easy, reliable, and fast way. Microbes can be identified on the basis of their peculiar cytometric parameters or by means of certain fluorochromes that can be used either independently or bound to specific antibodies or oligonucleotides. FCM has permitted the development of quantitative procedures to assess antimicrobial susceptibility and drug cytotoxicity in a rapid, accurate, and highly reproducible way. Furthermore, this technique allows the monitoring of in vitro antimicrobial activity and of antimicrobial treatments ex vivo. The most outstanding contribution of FCM is the possibility of detecting the presence of heterogeneous populations with different responses to antimicrobial treatments. Despite these advantages, the application of FCM in clinical microbiology is not yet widespread, probably due to the lack of access to flow cytometers or the lack of knowledge about the potential of this technique. One of the goals of this review is to attempt to mitigate this latter circumstance. We are convinced that in the near future, the availability of commercial kits should increase the use of this technique in the clinical microbiology laboratory. PMID:10755996

Laboratory activity to effectively teach introductory geomicrobiology concepts to non-geology majors.

PubMed

Marvasi, Massimiliano; Davila-Vazquez, Yarely C; Martinez, Lilliam Casillas

2013-01-01

We have designed a three-week experiment that can complement any microbiology course, to teach main geomicrobiology concepts for non-geology majors. One of the most difficult concepts for non-geology majors to comprehend is how bacteria serve as a platform for different mineralization reactions. In our three-week laboratory practice, students learn the main principles and conditions required for an induced bacterial mineralization. Upon completion of the laboratory experience, students will: 1) learn how microbial-induced mineralization (such as calcium carbonate formation) is affected by differential media and growth conditions; 2) understand how bacterial physiology affects any induced in situ or in vitro mineralization; 3) comprehend how growing conditions and bacterial physiologies interrelate, resulting in differential crystal formation. The teaching-learning process was assessed using a pre-/posttest with an increase from 26% to 76% in the number of positive answers from the students. We also measured the students' proficiency while conducting specific technical tasks, revealing no major difficulties while conducting the experiments. A final questionnaire was provided with satisfactory evaluations from the students regarding the organization and content of the practices. 84-86% of the students agreed that the exercises improved their knowledge in geomicrobiology and would like to attend similar laboratories in the future. Such response is the best indicator that the laboratory practice can be implemented in any undergraduate/graduate microbiology course to effectively teach basic geomicrobiology concepts to non-geology majors.

Laboratory Activity to Effectively Teach Introductory Geomicrobiology Concepts to Non-Geology Majors †

PubMed Central

Marvasi, Massimiliano; Davila-Vazquez, Yarely C.; Martinez, Lilliam Casillas

2013-01-01

We have designed a three-week experiment that can complement any microbiology course, to teach main geomicrobiology concepts for non-geology majors. One of the most difficult concepts for non-geology majors to comprehend is how bacteria serve as a platform for different mineralization reactions. In our three-week laboratory practice, students learn the main principles and conditions required for an induced bacterial mineralization. Upon completion of the laboratory experience, students will: 1) learn how microbial-induced mineralization (such as calcium carbonate formation) is affected by differential media and growth conditions; 2) understand how bacterial physiology affects any induced in situ or in vitro mineralization; 3) comprehend how growing conditions and bacterial physiologies interrelate, resulting in differential crystal formation. The teaching-learning process was assessed using a pre-/posttest with an increase from 26% to 76% in the number of positive answers from the students. We also measured the students’ proficiency while conducting specific technical tasks, revealing no major difficulties while conducting the experiments. A final questionnaire was provided with satisfactory evaluations from the students regarding the organization and content of the practices. 84–86% of the students agreed that the exercises improved their knowledge in geomicrobiology and would like to attend similar laboratories in the future. Such response is the best indicator that the laboratory practice can be implemented in any undergraduate/graduate microbiology course to effectively teach basic geomicrobiology concepts to non-geology majors. PMID:24358384

Evaluation of PDA Technical Report No 33. Statistical Testing Recommendations for a Rapid Microbiological Method Case Study.

PubMed

Murphy, Thomas; Schwedock, Julie; Nguyen, Kham; Mills, Anna; Jones, David

2015-01-01

New recommendations for the validation of rapid microbiological methods have been included in the revised Technical Report 33 release from the PDA. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This case study applies those statistical methods to accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological methods system being evaluated for water bioburden testing. Results presented demonstrate that the statistical methods described in the PDA Technical Report 33 chapter can all be successfully applied to the rapid microbiological method data sets and gave the same interpretation for equivalence to the standard method. The rapid microbiological method was in general able to pass the requirements of PDA Technical Report 33, though the study shows that there can be occasional outlying results and that caution should be used when applying statistical methods to low average colony-forming unit values. Prior to use in a quality-controlled environment, any new method or technology has to be shown to work as designed by the manufacturer for the purpose required. For new rapid microbiological methods that detect and enumerate contaminating microorganisms, additional recommendations have been provided in the revised PDA Technical Report No. 33. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This paper applies those statistical methods to analyze accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological method system being validated for water bioburden testing. The case study demonstrates that the statistical methods described in the PDA Technical Report No. 33 chapter can be successfully applied to rapid microbiological method data sets and give the same comparability results for similarity or difference as the standard method. © PDA, Inc. 2015.

Designing Cancer-Killing Artificial Viruses to Improve Student Understanding of Microbiology

PubMed Central

Kuniyuki, Andy; Sharp, Gwen

2011-01-01

Our objective was to assess the effectiveness of a “learning by designing” group project used in a lower-division Microbiology course. Students used knowledge gained from the course to design an artificial virus that would kill cancer cells. The assignment required groups to integrate the individual course topics into a unified, complex understanding of the field of microbiology. Throughout the course, students and the instructor collaborated in creating a rubric to evaluate the groups’ final presentations. This paper reports the results of an assessment of the project by comparing the instructor’s and the students’ scores for the presentations. Students’ and the instructor’s scores were correlated; the Pearson coefficient of 0.52 was statistically significant. The results indicate that students gained sufficient knowledge to accurately evaluate proposed designs. Additionally, the overall course grade distribution improved compared to the semester before the project was introduced. Finally, in order to engage students in thinking about their own learning process, they completed a reflection assignment that required them to discuss the changes in their understanding of microbiology over the course of the semester. Our assessment indicates that a design project can serve as an effective and useful learning technique in undergraduate Microbiology courses, though modifications are suggested. PMID:23653757

A Focus on the Death Kinetics in Predictive Microbiology: Benefits and Limits of the Most Important Models and Some Tools Dealing with Their Application in Foods

PubMed Central

Bevilacqua, Antonio; Speranza, Barbara; Sinigaglia, Milena; Corbo, Maria Rosaria

2015-01-01

Predictive Microbiology (PM) deals with the mathematical modeling of microorganisms in foods for different applications (challenge test, evaluation of microbiological shelf life, prediction of the microbiological hazards connected with foods, etc.). An interesting and important part of PM focuses on the use of primary functions to fit data of death kinetics of spoilage, pathogenic, and useful microorganisms following thermal or non-conventional treatments and can also be used to model survivors throughout storage. The main topic of this review is a focus on the most important death models (negative Gompertz, log-linear, shoulder/tail, Weibull, Weibull+tail, re-parameterized Weibull, biphasic approach, etc.) to pinpoint the benefits and the limits of each model; in addition, the last section addresses the most important tools for the use of death kinetics and predictive microbiology in a user-friendly way. PMID:28231222

Large IncHI2-plasmids encode extended-spectrum β-lactamases (ESBLs) in Enterobacter spp. bloodstream isolates, and support ESBL-transfer to Escherichia coli.

PubMed

Nilsen, E; Haldorsen, B C; Sundsfjord, A; Simonsen, G S; Ingebretsen, A; Naseer, U; Samuelsen, O

2013-11-01

We investigated the prevalence of extended-spectrum β-lactamases (ESBLs) in Enterobacter spp. bloodstream isolates from 19 hospital laboratories in Norway during 2011. A total of 62/230 (27%) isolates were resistant to third-generation cephalosporins and four (1.7%) were ESBL-positive; blaCTX -M-15 (n = 3) and blaSHV -12 (n = 1). This is comparable to the prevalence of ESBLs in clinical isolates of Escherichia coli and Klebsiella pneumoniae in Norway during the same period. All ESBL-positive isolates were multidrug resistant (MDR) and harboured plasmid-mediated quinolone resistance. Three isolates supported transfer of large IncHI2-plasmids harbouring ESBL- and MDR-encoding genes to E. coli recipients by in vitro conjugation. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

Comparison of sampling procedures and microbiological and non-microbiological parameters to evaluate cleaning and disinfection in broiler houses.

PubMed

Luyckx, K; Dewulf, J; Van Weyenberg, S; Herman, L; Zoons, J; Vervaet, E; Heyndrickx, M; De Reu, K

2015-04-01

Cleaning and disinfection of the broiler stable environment is an essential part of farm hygiene management. Adequate cleaning and disinfection is essential for prevention and control of animal diseases and zoonoses. The goal of this study was to shed light on the dynamics of microbiological and non-microbiological parameters during the successive steps of cleaning and disinfection and to select the most suitable sampling methods and parameters to evaluate cleaning and disinfection in broiler houses. The effectiveness of cleaning and disinfection protocols was measured in six broiler houses on two farms through visual inspection, adenosine triphosphate hygiene monitoring and microbiological analyses. Samples were taken at three time points: 1) before cleaning, 2) after cleaning, and 3) after disinfection. Before cleaning and after disinfection, air samples were taken in addition to agar contact plates and swab samples taken from various sampling points for enumeration of total aerobic flora, Enterococcus spp., and Escherichia coli and the detection of E. coli and Salmonella. After cleaning, air samples, swab samples, and adenosine triphosphate swabs were taken and a visual score was also assigned for each sampling point. The mean total aerobic flora determined by swab samples decreased from 7.7±1.4 to 5.7±1.2 log CFU/625 cm2 after cleaning and to 4.2±1.6 log CFU/625 cm2 after disinfection. Agar contact plates were used as the standard for evaluating cleaning and disinfection, but in this study they were found to be less suitable than swabs for enumeration. In addition to measuring total aerobic flora, Enterococcus spp. seemed to be a better hygiene indicator to evaluate cleaning and disinfection protocols than E. coli. All stables were Salmonella negative, but the detection of its indicator organism E. coli provided additional information for evaluating cleaning and disinfection protocols. Adenosine triphosphate analyses gave additional information about the hygiene level of the different sampling points. © 2015 Poultry Science Association Inc.

Prevention of artificial dental plaque formation in vitro by plant extracts.

PubMed

Smullen, J; Finney, M; Storey, D M; Foster, H A

2012-10-01

A number of previous studies have shown that plant extracts can inhibit formation of dental plaque. The ability of extracts of Rosmarinus officianalis L., Salvia officianalis L., unfermented cocoa, red grape seed and green tea to inhibit plaque bacteria, glucosyltransferase activity, glucan and plaque formation in an in vitro model using bovine teeth was examined. The antimicrobial activity of the plant extracts against oral bacteria was determined using a standard susceptibility agar dilution technique. Inhibition of growth and acid production from glucose and sucrose by Streptococcus mutans in liquid culture was investigated. Prevention of plaque formation on bovine teeth initiated by Strep. mutans was studied using an artificial mouth. The plant extracts inhibited the growth of oral bacteria and prevented acid production by Strep. mutans. Extracts inhibited glucosyltransferase activity and glucan production and inhibited adhesion to glass. Extracts of R. officianalis L. and S. officianalis L. at 0·25 mg ml(-1) reduced plaque growth by >80%. Green tea extract completely inhibited plaque formation but resulted in a greenish discolouration of the teeth which could not be removed by scrubbing. The plant extracts, particularly those from R. officianalis L. and S. officianalis L., inhibited glucosyltranferase activity, glucan production and plaque formation in vitro. The results suggest that the extracts of R. officianalis L. and S. officianalis L. may be useful as antiplaque agents in foods and dental preparations. Bovine teeth can be used as an alternative to hydroxyapatite for studies of plaque formation, but they need to be carefully sterilized before use. © 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

Evaluation of the performance of the IQ-check kits and the USDA microbiology laboratory guidebook methods for detection of Shiga Toxin-Producing E. coli (STEC) and STEC and Salmonella simultaneously in ground beef

USDA-ARS?s Scientific Manuscript database

Aims: To evaluate the performance of the IQ-Check kits and the USDA Microbiology Laboratory Guidebook (MLG) methods for detection of the top 7 Shiga toxin-producing E. coli (STEC) (O157:H7, O26, O45, O103, O111, O121, and O145) in ground beef and both STEC and Salmonella in co-inoculated samples. M...

Adopt a Bacterium - an active and collaborative learning experience in microbiology based on social media.

PubMed

Piantola, Marco Aurélio Floriano; Moreno, Ana Carolina Ramos; Matielo, Heloísa Alonso; Taschner, Natalia Pasternak; Cavalcante, Rafael Ciro Marques; Khan, Samia; Ferreira, Rita de Cássia Café

2018-04-24

The "Adopt a Bacterium" project is based on the use of social network as a tool in Microbiology undergraduate education, improving student learning and encouraging students to participate in collaborative learning. The approach involves active participation of both students and teachers, emphasizing knowledge exchange, based on widely used social media. Students were organized in groups and asked to adopt a specific bacterial genus and, subsequently, submit posts about "adopted genus". The formative assessment is based on posting information on Facebook®, and the summative assessment involves presentation of seminars about the adopted theme. To evaluate the project, students filled out three anonymous and voluntary surveys. Most of the students enjoyed the activities and positively evaluated the experience. A large amount of students declared a change in their attitude towards the way they processed information, especially regarding the use of scientific sources. Finally, we evaluated knowledge retention six months after the end of the course and students were able to recall relevant Microbiology concepts. Our results suggest that the "Adopt a Bacterium" project represents a useful strategy in Microbiology learning and may be applied to other academic fields. Copyright © 2018 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

One Small Step for the Gram Stain, One Giant Leap for Clinical Microbiology.

PubMed

Thomson, Richard B

2016-06-01

The Gram stain is one of the most commonly performed tests in the clinical microbiology laboratory, yet it is poorly controlled and lacks standardization. It was once the best rapid test in microbiology, but it is no longer trusted by many clinicians. The publication by Samuel et al. (J. Clin. Microbiol. 54:1442-1447, 2016, http://dx.doi.org/10.1128/JCM.03066-15) is a start for those who want to evaluate and improve Gram stain performance. In an age of emerging rapid molecular results, is the Gram stain still relevant? How should clinical microbiologists respond to the call to reduce Gram stain error rates? Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Macrolones Are a Novel Class of Macrolide Antibiotics Active against Key Resistant Respiratory Pathogens In Vitro and In Vivo.

PubMed

Čipčić Paljetak, Hana; Verbanac, Donatella; Padovan, Jasna; Dominis-Kramarić, Miroslava; Kelnerić, Željko; Perić, Mihaela; Banjanac, Mihailo; Ergović, Gabrijela; Simon, Nerrisa; Broskey, John; Holmes, David J; Eraković Haber, Vesna

2016-09-01

As we face an alarming increase in bacterial resistance to current antibacterial chemotherapeutics, expanding the available therapeutic arsenal in the fight against resistant bacterial pathogens causing respiratory tract infections is of high importance. The antibacterial potency of macrolones, a novel class of macrolide antibiotics, against key respiratory pathogens was evaluated in vitro and in vivo MIC values against Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, and Haemophilus influenzae strains sensitive to macrolide antibiotics and with defined macrolide resistance mechanisms were determined. The propensity of macrolones to induce the expression of inducible erm genes was tested by the triple-disk method and incubation in the presence of subinhibitory concentrations of compounds. In vivo efficacy was assessed in a murine model of S. pneumoniae-induced pneumonia, and pharmacokinetic (PK) profiles in mice were determined. The in vitro antibacterial profiles of macrolones were superior to those of marketed macrolide antibiotics, including the ketolide telithromycin, and the compounds did not induce the expression of inducible erm genes. They acted as typical protein synthesis inhibitors in an Escherichia coli transcription/translation assay. Macrolones were characterized by low to moderate systemic clearance, a large volume of distribution, a long half-life, and low oral bioavailability. They were highly efficacious in a murine model of pneumonia after intraperitoneal application even against an S. pneumoniae strain with constitutive resistance to macrolide-lincosamide-streptogramin B antibiotics. Macrolones are the class of macrolide antibiotics with an outstanding antibacterial profile and reasonable PK parameters resulting in good in vivo efficacy. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

In vitro model of production of antibodies; a new approach to reveal the presence of key bacteria in polymicrobial environments.

PubMed

Wu, Chongcong; Nakka, Sravya; Mansouri, Sepahdar; Bengtsson, Torbjörn; Nayeri, Tayeb; Nayeri, Fariba

2016-09-09

There is a rapid emergence of multiple resistant gram-negative bacteria due to overuse of antibiotics in the treatment of infections. Biofilms consist of polymicrobial communities that survive the host's defense system. The key bacteria in biofilms are slow growing and support an attachment and rapid growth of other microorganisms. Current antimicrobial strategies often fail due to poor diagnosis of key pathogens in biofilms. The study aims to develop anti-bacterial human antibodies in vitro from patients who had recently undergone a systemic infection by pathogenic bacteria and to use these antibodies as a tool for detecting bacteria in biofilms. Lymphocytes were separated from whole blood of patients (n = 10) and stimulated with heat-killed bacteria to produce antibodies in vitro. The specificity of antibodies in recognizing the bacteria against which they were directed was evaluated by surface plasmon resonance system (SPR) and electron microscopy. The ulcer secretions from patients with chronic and acute leg ulcers and healthy controls were analyzed by the SPR system and the results were compared with culture studies. The produced antibodies recognized bacteria with high sensitivity (SPR). The antibodies against Enterococcus fecalis bound specifically to the microorganism in a bacterial co-culture that was visualized by electron microscopy. In the present work, a method for producing specific antibodies against bacteria is introduced to recognize bacterial components in body fluids of patients suffering from pathogenic biofilms. This diagnostic technique may be most useful in clinical microbiology and in the choice of antibiotics in the treatment of serious infections.

Streptococcus dysgalactiae subsp. dysgalactiae isolated from milk of the bovine udder as emerging pathogens: In vitro and in vivo infection of human cells and zebrafish as biological models.

PubMed

Alves-Barroco, Cinthia; Roma-Rodrigues, Catarina; Raposo, Luís R; Brás, Catarina; Diniz, Mário; Caço, João; Costa, Pedro M; Santos-Sanches, Ilda; Fernandes, Alexandra R

2018-03-25

Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) is a major cause of bovine mastitis and has been regarded as an animal-restricted pathogen, although rare infections have been described in humans. Previous studies revealed the presence of virulence genes encoded by phages of the human pathogen Group A Streptococcus pyogenes (GAS) in SDSD isolated from the milk of bovine udder with mastitis. The isolates SDSD VSD5 and VSD13 could adhere and internalize human primary keratinocyte cells, suggesting a possible human infection potential of bovine isolates. In this work, the in vitro and in vivo potential of SDSD to internalize/adhere human cells of the respiratory track and zebrafish as biological models was evaluated. Our results showed that, in vitro, bovine SDSD strains could interact and internalize human respiratory cell lines and that this internalization was dependent on an active transport mechanism and that, in vivo, SDSD are able to cause invasive infections producing zebrafish morbidity and mortality. The infectious potential of these isolates showed to be isolate-specific and appeared to be independent of the presence or absence of GAS phage-encoded virulence genes. Although the infection ability of the bovine SDSD strains was not as strong as the human pathogenic S. pyogenes in the zebrafish model, results suggested that these SDSD isolates are able to interact with human cells and infect zebrafish, a vertebrate infectious model, emerging as pathogens with zoonotic capability. © 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Development, Dissemination, and Preimplementation Evaluation of Food Safety Educational Materials for Secondary Education

ERIC Educational Resources Information Center

Shearer, Adrienne E. H.; Snider, O. Sue; Kniel, Kalmia E.

2013-01-01

With the persistence of microbiological foodborne illness and anticipated future shortage of scientists with agricultural and food science expertise in the United States, it is imperative to educate youth on microbiological food safety and enhance their awareness of opportunities to become engaged in finding solutions to food safety challenges. To…

Microbiology and evisceration efficiency of broiler carcasses slaughtered and held up to 8 hours postmortem prior to scalding and defeathering

USDA-ARS?s Scientific Manuscript database

The implementation of on farm slaughter could eliminate potential animal welfare issues associated with cooping, transport, dumping, and shackling live broilers. This research evaluated evisceration efficiency and the microbiological implications of delaying scalding and defeathering for up to 8 h a...

Evaluation of the stability and antimicrobial activity of an ethanolic extract of Libidibia ferrea

PubMed Central

de Oliveira Marreiro, Raquel; Bandeira, Maria Fulgência Costa Lima; de Souza, Tatiane Pereira; de Almeida, Mailza Costa; Bendaham, Katiana; Venâncio, Gisely Naura; Rodrigues, Isis Costa; Coelho, Cristiane Nagai; Milério, Patrícia Sâmea Lêdo Lima; de Oliveira, Glauber Palma; de Oliveira Conde, Nikeila Chacon

2014-01-01

Biofilm is a dense, whitish, noncalcified aggregate of bacteria, with desquamated epithelial cells and food debris creating conditions for an imbalance of resident oral microflora and favoring the destruction of hard and soft tissues by development of caries and gingivitis. The aim of this study was to obtain and characterize an extract of Libidibia ferrea, ex Caesalpinia ferrea L. and to evaluate its feasibility for formulation as a mouthwash, according to current legislation. For this purpose, pH, sedimentation, density, and stability were evaluated, along with microbiological testing of the extract. The microbiological test was used to verify the presence of Staphylococcus aureus, Pseudomonas aeruginosa, fungi, yeasts, coliforms, and minimum inhibitory concentrations of Streptococcus mutans and Streptococcus oralis strains. Characterization, microbiological evaluation, and minimum inhibitory concentration results were tabulated and described using descriptive statistics. The L. ferrea extract showed stable characteristics, product quality, and antibacterial activity against the microorganisms tested irrespective of experimental time intervals. According to these results, it can be concluded that formulation of a mouthwash containing L. ferrea extract to control biofilm is feasible, but further studies are needed. PMID:24501546

Inhibition of the β-Lactamase BlaMab by Avibactam Improves the In Vitro and In Vivo Efficacy of Imipenem against Mycobacterium abscessus.

PubMed

Lefebvre, Anne-Laure; Le Moigne, Vincent; Bernut, Audrey; Veckerlé, Carole; Compain, Fabrice; Herrmann, Jean-Louis; Kremer, Laurent; Arthur, Michel; Mainardi, Jean-Luc

2017-04-01

Mycobacterium abscessus pulmonary infections are treated with a macrolide (clarithromycin or azithromycin), an aminoglycoside (amikacin), and a β-lactam (cefoxitin or imipenem). The triple combination is used without any β-lactamase inhibitor, even though M abscessus produces the broad-spectrum β-lactamase Bla Mab We determine whether inhibition of Bla Mab by avibactam improves the activity of imipenem against M. abscessus The bactericidal activity of drug combinations was assayed in broth and in human macrophages. The in vivo efficacy of the drugs was tested by monitoring the survival of infected zebrafish embryos. The level of Bla Mab production in broth and in macrophages was compared by quantitative reverse transcription-PCR and Western blotting. The triple combination of imipenem (8 or 32 μg/ml), amikacin (32 μg/ml), and avibactam (4 μg/ml) was bactericidal in broth (<0.1% survival), with 3.2- and 4.3-log 10 reductions in the number of CFU being achieved at 72 h when imipenem was used at 8 and 32 μg/ml, respectively. The triple combination achieved significant intracellular killing, with the bacterial survival rates being 54% and 7% with the low (8 μg/ml) and high (32 μg/ml) dosages of imipenem, respectively. In vivo inhibition of Bla Mab by avibactam improved the survival of zebrafish embryos treated with imipenem. Expression of the gene encoding Bla Mab was induced (20-fold) in the infected macrophages. Inhibition of Bla Mab by avibactam improved the efficacy of imipenem against M. abscessus in vitro , in macrophages, and in zebrafish embryos, indicating that this β-lactamase inhibitor should be clinically evaluated. The in vitro evaluation of imipenem may underestimate the impact of Bla Mab , since the production of the β-lactamase is inducible in macrophages. Copyright © 2017 American Society for Microbiology.

Hypocrea lixii, novel endophytic fungi producing anticancer agent cajanol, isolated from pigeon pea (Cajanus cajan [L.] Millsp.).

PubMed

Zhao, J; Li, C; Wang, W; Zhao, C; Luo, M; Mu, F; Fu, Y; Zu, Y; Yao, M

2013-07-01

The aim was to isolate, identify and characterize endophytes from pigeon pea (Cajanus cajan [L.] Millsp.), as novel producer of cajanol and its in vitro cytotoxicity assay. Isolation, identification and characterization of novel endophytes producing cajanol from the roots of pigeon pea were investigated. The endophytes were identified as Hypocrea lixii by morphological and molecular methods. Cajanol produced by endophytes were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). R-18 produced the highest levels of cajanol (322·4 ± 10·6 μg l(-1) or 102·8 ± 6·9 μg g(-1) dry weight of mycelium) after incubation for 7 days. The cytotoxicity towards human lung carcinoma cells (A549) of fungal cajanol was investigated in vitro. First, a novel endophyte Hypocrea lixii, producing anticancer agent cajanol, was isolated from the host pigeon pea (Cajanus cajan [L.] Millsp.). Fungal cajanol possessed stronger cytotoxicity activity towards A549 cells in time- and dose-dependent manners. This endophyte is a potential handle for scientific and commercial exploitation, and it could provide a promising alterative approach for large-scale production of cajanol to satisfy new anticancer drug development. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

Effects of chlorhexidine on a tongue-flora microcosm and VSC production using an in vitro biofilm perfusion model.

PubMed

Greenman, J; McKenzie, C; Saad, S; Wiegand, B; Zguris, J C

2008-12-01

An in vitro perfusion biofilm model, derived from tongue-scrape microflora removed from one individual, was employed to study sulfide biogenesis and the effects of repeated exposure to chlorhexidine (CHX). Volatile sulfur compounds (VSC) were measured using a carbon veil electrode within the biofilm and a halimeter for liquid and gas phase levels, respectively. The microflora of the perfusate and the biofilm were assessed by microbiological techniques and polymerase chain reaction (PCR) to estimate diversity. Biofilms treated with a 1 mL pulse of 0.1% CHX twice a day for three days showed (1) a large reduction in viable count (>90% kill), (2) a (slow) reduction in the VSC production rate, consistent with the reduction in microbes rather than direct inhibitory effects on the biotransformation steps, and (3) a preferential reduction of strict anaerobes. Treated biofilms allowed to recover over 3-5 days showed a nominal amount of regrowth in some experiments, although population numbers were still well below those found in untreated controls. The microbiological composition of biofilms treated but allowed to recover was markedly different from the controls, with proportionally fewer strict anaerobes. Thus, CHX treatment caused detectable ecological shifts with consequent long-term effects on the response of the biofilm in terms of VSC generation, consistent with clinical observations. The model appears highly suited for testing the efficacy of putative anti-malodour or antimicrobial agents.

Use of the Real Time xCelligence System for Purposes of Medical Microbiology.

PubMed

Junka, Adam Feliks; Janczura, Adriana; Smutnicka, Danuta; Mączyńska, Beata; Anna, Secewicz; Nowicka, Joanna; Bartoszewicz, Marzenna; Gościniak, Grażyna

2012-09-28

Roche's xCelligence impedance-measuring instrument is one of a few commercially available systems of such type. According to the best knowledge of authors, instrument was tested so far only for eukaryotic cell research. The aim of this work was to estimate xCELLigence suitability for the microbiological tests, including (i) measurement of morphological changes in eukaryotic cells as a result of bacterial toxin activity, (ii) measurement of bacterial biofilm formation and (iii) impact of antiseptics on the biofilm structure. To test the infuence of bacterial LT enterotoxin on eukaryotic cell lines, Chinese Hamster Ovary (CHO) cell line and reference strain Escherichia coli ATTC 35401 were used. To investigate Roche's instrument ability to measure biofilm formation and impact of antiseptics on its development, Staphylococcus aureus ATTC6538 reference strain was used. The data generated during the experiments indicate excellent ability of xCelligence instrument to detect cytopathic effect caused by bacterial LT endotoxin and to detect staphylococcal biofilm formation. However, interpretation of the results obtained during real-time measurement of antiseptic's bactericidal activity against staphylococcal biofilm, caused many difficulties. xCelligence instrument can be used for real-time monitoring of morphological changes in CHO cells treated with bacterial LT enterotoxin and for real-time measurement of staphylococcal biofilm formation in vitro. Further investigation is necessary to confirm suitability of system to analyze antiseptic's antimicrobial activity against biofilm in vitro.

Biofilm inhibitory and eradicating activity of wound care products against Staphylococcus aureus and Staphylococcus epidermidis biofilms in an in vitro chronic wound model.

PubMed

Brackman, G; De Meyer, L; Nelis, H J; Coenye, T

2013-06-01

Although several factors contribute to wound healing, bacterial infections and the presence of biofilm can significantly affect healing. Despite that this clearly indicates that therapies should address biofilm in wounds, only few wound care products have been evaluated for their antibiofilm effect. For this reason, we developed a rapid quantification approach to investigate the efficacy of wound care products on wounds infected with Staphylococcus spp. An in vitro chronic wound infection model was used in which a fluorescent Staph. aureus strain was used to allow the rapid quantification of the bacterial burden after treatment. A good correlation was observed between the fluorescence signal and the bacterial counts. When evaluated in this model, several commonly used wound dressings and wound care products inhibited biofilm formation resulting in a decrease between one and seven log CFU per biofilm compared with biofilm formed in the absence of products. In contrast, most dressings only moderately affected mature biofilms. Our model allowed the rapid quantification of the bacterial burden after treatment. However, the efficacy of treatment varied between the different types of dressings and/or wound care products. Our model can be used to compare the efficacy of wound care products to inhibit biofilm formation and/or eradicate mature biofilms. In addition, the results indicate that treatment of infected wounds should be started as soon as possible and that novel products with more potent antibiofilm activity are needed. © 2013 The Society for Applied Microbiology.

Development and Evaluation of Problem-Solving Skills in Microbiology.

ERIC Educational Resources Information Center

Schuytema, Eunice C.; And Others

A problem solving, laboratory experience was devised in which first-year medical students were given a case description and then required to make judgments about what microbiology specimens should be collected and to analyze the results of laboratory tests in terms of implications for patient care. Over a four-year period revisions were made in…

Learning about Foodborne Pathogens: Evaluation of Student Perceptions of Group Project Work in a Food Microbiology Course

ERIC Educational Resources Information Center

Turner, Mark S.

2009-01-01

This study examined the experiences of students in an active learning group work exercise in an introductory food microbiology course involving the study of foodborne pathogens. Small groups were required to access, analyze, and present information regarding a single food poisoning bacterium. The presentations contained features and…

Microbiological safety of commercial prime rib preparation methods: thermal inactivation of Salmonella spp. in mechanically tenderized beef roasts

USDA-ARS?s Scientific Manuscript database

A survey of food service operations in a medium-size Midwestern city was conducted to evaluate the microbiological safety of prime rib preparation methods relative to survival of Salmonella spp. in both intact and tenderized (non-intact) product. All six restaurants visited seared rib eye roasts (ai...

Teaching Emerging Diseases: A Strategy for Succeeding with Nonmajors

PubMed Central

FASS, MARION FIELD

2000-01-01

A nonmajors course on emerging diseases served to introduce students to basic concepts in microbiology and to improve scientific literacy. The course used a range of learner-centered approaches to encourage students to take responsibility for their own learning. Evaluations demonstrated both student satisfaction and an increased understanding of important issues in microbiology. PMID:23653535

Future of diagnostic microbiology.

PubMed

Khardori, N

2014-01-01

Diagnostic Microbiology is the tool that makes it possible to identify the exact etiology of infectious diseases and the most optimal therapy at the level of individual patients as well as communities. Conventional methods require time to grow the microbes in vitro under specific conditions and not all microbes are easily cultivable. This is followed by biochemical methods for identification which also require hours and sometimes days. Transport of the specimens under less than ideal conditions, prior use of antibiotics and small number of organisms are among the factors that render culture-based methods less reliable. Newer methods depend on amplification of nucleic acids followed by use of probes for identification. This mitigates the need for higher microbial load, presence of metabolically active viable organisms and shortens the time to reporting. These methods can be used to detect antibiotic resistance genes directly from the specimen and help direct targeted therapy. Since these methods will not fulfill all the diagnostic needs, a second approach is being used to shorten the time to identification after the organism has already grown. Mass spectrometry and bioinformatics are the tools making this possible. This review gives a historical perspective on diagnostic microbiology, discusses the pitfalls of current methodology and provides an overview of newer and future methods.

Bioterrorism: a Laboratory Who Does It?

PubMed Central

Lee, Philip A.; Rowlinson, Marie-Claire

2014-01-01

In October 2001, the first disseminated biological warfare attack was perpetrated on American soil. Initially, a few clinical microbiology laboratories were testing specimens from acutely ill patients and also being asked to test nasal swabs from the potentially exposed. Soon after, a significant number of clinical microbiology and public health laboratories received similar requests to test the worried well or evaluate potentially contaminated mail or environmental materials, sometimes from their own break rooms. The role of the clinical and public health microbiology laboratory in response to a select agent event or act of bioterrorism is reviewed. PMID:24648550

Microorganisms in the deposits of cold carbon mineral waters of the Russian Far East and their habitats

NASA Astrophysics Data System (ADS)

Kalitina, E. G.; Kharitonova, N. A.; Kuzmina, T. V.; Chelnokov, G. A.

2018-01-01

Study of the chemical composition of carbon mineral waters has shown the prevalence of calcium, magnesium and sodium among the cations, sulfate, nitrate and chloride ions among the anions, and ferric iron, strontium and manganese in the microelement composition. Results of the microbiological studies have revealed that carbon mineral waters contain various microorganisms that can transform the physical and chemical composition of mineral waters by interfering with geochemical cycles. The sanitary and microbiological properties of carbon mineral waters have been evaluated thus proving that the waters of Medvezhii (Shmakovskoe deposit) are microbiologically clean.

In Vitro Antimicrobial Susceptibility Patterns of Blastocystis.

PubMed

Roberts, Tamalee; Bush, Stephen; Ellis, John; Harkness, John; Stark, Damien

2015-08-01

Blastocystis is the most common human enteric protist with controversial clinical significance. Metronidazole is considered a first-line treatment for Blastocystis infection; however, there has been increasing evidence for the lack of efficacy of this treatment. Treatment failure has been reported in several clinical cases, and recent in vitro studies have suggested the occurrence of metronidazole-resistant strains. In this study, we tested 12 Blastocystis isolates from 4 common Blastocystis subtypes (ST1, ST3, ST4, and ST8) against 12 commonly used antimicrobials (metronidazole, paromomycin, ornidazole, albendazole, ivermectin, trimethoprim-sulfamethoxazole [TMP-SMX], furazolidone, nitazoxanide, secnidazole, fluconazole, nystatin, and itraconazole) at 10 different concentrations in vitro. It was found that each subtype showed little sensitivity to the commonly used metronidazole, paromomycin, and triple therapy (furazolidone, nitazoxanide, and secnidazole). This study highlights the efficacy of other potential drug treatments, including trimethoprim-sulfamethoxazole and ivermectin, and suggests that current treatment regimens be revised. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Nitric oxide nanoparticles: pre-clinical utility as a therapeutic for intramuscular abscesses.

PubMed

Schairer, David; Martinez, Luis R; Blecher, Karin; Chouake, Jason; Nacharaju, Parimala; Gialanella, Philip; Friedman, Joel M; Nosanchuk, Joshua D; Friedman, Adam

2012-01-01

Nitric oxide (NO) is a critical component of host defense against invading pathogens; however, its therapeutic utility is limited due to a lack of practical delivery systems. Recently, a NO-releasing nanoparticulate platform (NO-np) was shown to have in vitro broad-spectrum antimicrobial activity and in vivo pre-clinical efficacy in a dermal abscess model. To extend these findings, both topical (TP) and intralesional (IL) NO-np administration was evaluated in a MRSA intramuscular murine abscess model and compared with vancomycin. All treatment arms accelerated abscess clearance clinically, histologically, and by microbiological assays on both days 4 and 7 following infection. However, abscesses treated with NO-np via either route demonstrated a more substantial, statistically significant decrease in bacterial survival based on colony forming unit assays and histologically revealed less inflammatory cell infiltration and preserved muscular architecture. These data suggest that the NO-np may be an effective addition to our armament for deep soft tissue infections.

Differential Activity of the Oral Glucan Synthase Inhibitor SCY-078 against Wild-Type and Echinocandin-Resistant Strains of Candida Species.

PubMed

Pfaller, Michael A; Messer, Shawn A; Rhomberg, Paul R; Borroto-Esoda, Katyna; Castanheira, Mariana

2017-08-01

SCY-078 (formerly MK-3118) is a novel orally active inhibitor of fungal β-(1,3)-glucan synthase (GS). SCY-078 is a derivative of enfumafungin and is structurally distinct from the echinocandin class of antifungal agents. We evaluated the in vitro activity of this compound against wild-type (WT) and echinocandin-resistant isolates containing mutations in the FKS genes of Candida spp. Against 36 Candida spp. FKS mutants tested, 30 (83.3%) were non-WT to 1 or more echinocandins, and only 9 (25.0%) were non-WT (MIC, >WT-upper limit) to SCY-078. Among C. glabrata isolates carrying FKS alterations, 84.0% were non-WT to the echinocandins versus only 24.0% for SCY-078. In contrast to the echinocandin comparators, the activity of SCY-078 was minimally affected by the presence of FKS mutations, suggesting that this agent is useful in the treatment of Candida infections due to echinocandin-resistant strains. Copyright © 2017 American Society for Microbiology.

Response surface optimization of extraction protocols to obtain phenolic rich antioxidant from sea buckthorn and their potential application into model meat system.

PubMed

Wagh, Rajesh V; Chatli, Manish K

2017-05-01

In the present study, processing parameters for the extraction of phenolic rich sea buckthorn seed (SBTE) extract were optimised using response surface method and subjected for in vitro efficacy viz. total phenolic, ABTS, DPPH and SASA activity. The optimised model depicted MeOH as a solvent at 60% concentration level with a reaction time of 20 min and extracting temperature of 55 °C for the highest yield and total phenolic content. The efficacy of different concentration of obtained SBT was evaluated in raw ground pork as a model meat system on the basis of various physico-chemical, microbiological, sensory quality characteristics. Addition of 0.3% SBTE significantly reduced the lipid peroxidation (PV, TBARS and FFA) and improved instrumental colour ( L* , a*, b* ) attributes of raw ground pork during refrigerated storage of 9 days. Results concluded that SBTE at 0.3% level can successfully improve the oxidative stability, microbial, sensory quality attributes in the meat model system.

Chitosan/alginate complexes for vaginal delivery of chlorhexidine digluconate.

PubMed

Abruzzo, A; Bigucci, F; Cerchiara, T; Saladini, B; Gallucci, M C; Cruciani, F; Vitali, B; Luppi, B

2013-01-16

Chitosan/alginate complexes were prepared at different polycation/polyanion molar ratios and freeze-dried vaginal inserts were obtained for chlorhexidine digluconate local delivery in genital infections. Complex yield, FT-IR spectra, and TGA thermograms were studied to confirm the interaction between the two polyions. The influence of different complexes on physical handling, morphology, and drug distribution in the samples were evaluated by friability test, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS), respectively. In vitro water-uptake, mucoadhesion and release tests were performed as well as microbiological tests toward pathogenic vaginal microorganisms. The results showed that the selection of suitable chitosan/alginate molar ratio and drug loading allowed modulate insert ability to hydrate, adhere to the mucosa, and release chlorhexidine digluconate. The insert containing an excess of alginate was found to be the best performing formulation and showed good antimicrobial activity toward the pathogens Candida albicans and Escherichia coli. Copyright © 2012 Elsevier Ltd. All rights reserved.

[Abnormal vaginal secretion: sensitivity, specificity and concordance between clinical and cytological diagnosis].

PubMed

de Camargo, Kélvia Cristina; Alves, Rosane Ribeiro Figueiredo; Baylão, Luciano Augusto; Ribeiro, Andrea Alves; Araujo, Nadja Lindany Alves de Souza; Tavares, Suelene Brito do Nascimento; dos Santos, Sílvia Helena Rabelo

2015-05-01

To estimate the prevalence of bacterial vaginosis (BV), candidiasis and trichomoniasis and compare the findings of physical examination of the vaginal secretion with the microbiological diagnosis obtained by cytology study of a vaginal smear using the Papanicolaou method. A cross-sectional study of 302 women aged 20 to 87 years, interviewed and submitted to a gynecology test for the evaluation of vaginal secretion and collection of a cytology smear, from June 2012 to May 2013. Sensitivity analyses were carried out and specificity, positive predictive value (PPV) and negative predictive value (NPV) with their respective 95%CI were determined to assess the accuracy of the characteristics of vaginal secretion in relation to the microbiological diagnosis of the cytology smear . The kappa index (k) was used to assess the degree of agreement between the clinical features of vaginal secretion and the microbiological findings obtained by cytology. RESULTS The prevalence of BV, candidiasis and trichomoniasis was 25.5, 9.3 and 2.0%, respectively. The sensitivity, specificity, PPV and NPV of the clinical characteristics of vaginal secretion for the cytological diagnosis of BV were 74, 78.6, 54.3 and 89.9%, respectively. The sensitivity, specificity, PPV and the NPV of the clinical characteristics of vaginal secretion for the cytological diagnosis of candidiasis were 46.4, 86.2, 25.5 and 94%, respectively. The correlation between the clinical evaluation of vaginal secretion and the microbiological diagnosis of BV, candidiasis and trichomoniasis, assessed by the kappa index, was 0.47, 0.23 and 0.28, respectively. CONCLUSION The most common cause of abnormal vaginal secretion was BV. The clinical evaluation of vaginal secretion presented amoderate to weak agreement with the microbiological diagnosis, indicating the need for complementary investigation of the clinical findings of abnormal vaginal secretion.

Evaluation of microbiological, cellular and risk factors associated with subclinical mastitis in female buffaloes

PubMed Central

de Oliveira Moura, Emmanuella; do Nascimento Rangel, Adriano Henrique; de Melo, Maria Celeste Nunes; Borba, Luiz Henrique Fernandes; de Lima Júnior, Dorgival Morais; Novaes, Luciano Patto; Urbano, Stela Antas; de Andrade Neto, Júlio César

2017-01-01

Objective This study aimed to evaluate the microbiological and cellular milk profile for the diagnosis of subclinical mastitis in female buffaloes and to assess risk factors for predisposition of the disease. Methods Analyses were carried out by standard plate count (SPC), identification of species and antibiotic resistance, somatic cell count (SCC), electrical electrical conductivity of milk (ECM), and lactoferrin content in milk. Teat cups were swabbed to evaluate risk factors, observing hyperkeratosis, milking vacuum pressure and cleanliness of the site. Hence, 30 female buffaloes were randomly selected (15 from a group in early lactation and 15 in late lactation). Results The most common bacteria in the microbiological examination were Staphylococcus spp., Streptococcus spp. and Corynebacterium sp. In the antibiotic sensitivity test, 10 (58.82%) of the 17 antibiotics tested were sensitive to all isolates, and resistant bacteria were Streptococcus uberis, Streptococcus dysgalactiae, Streptococcus haemolyticus, and Escherichia coli. It was observed that positive samples in the microbiological examination showed total bacterial count between 9.10×103 to 6.94×106 colony forming units/mL, SCC between 42,000 to 4,320,000 cells/mL and ECM ranging from 1.85 to 7.40 mS/cm. It was also found that the teat cups had high microbial counts indicating poor hygiene, and even faults in the cleanliness of the animals’ waiting room were observed. It is concluded that values of SCC above 537,000 cells/mL and ECM above 3.0 mS/mL are indications of mammary gland infection for this herd; however, the association of these values with a microbiological analysis is necessary to more accurately evaluate the health status of mammary glands with subclinical mastitis. Conclusion Through phenotypic characterization of bacteria involved in the samples, the genera Staphylococcus spp., Streptococcus spp., and Corynebacterimum bovis were the most prevalent in this study. Faults in environment and equipment hygienization are factors that are directly associated with mastitis. PMID:28183165

Implications of Antimicrobial Combinations in Complex Wound Biofilms Containing Fungi.

PubMed

Townsend, Eleanor M; Sherry, Leighann; Kean, Ryan; Hansom, Donald; Mackay, William G; Williams, Craig; Butcher, John; Ramage, Gordon

2017-09-01

Diabetic foot ulcer treatment currently focuses on targeting bacterial biofilms, while dismissing fungi. To investigate this, we used an in vitro biofilm model containing bacteria and fungi, reflective of the wound environment, to test the impact of antimicrobials. Here we showed that while monotreatment approaches influenced biofilm composition, this had no discernible effect on overall quantity. Only by combining bacterium- and fungus-specific antibiotics were we able to decrease the biofilm bioburden, irrespective of composition. Copyright © 2017 American Society for Microbiology.

Kombucha, the fermented tea: microbiology, composition, and claimed health effects.

PubMed

Greenwalt, C J; Steinkraus, K H; Ledford, R A

2000-07-01

Kombucha is a slightly sweet, slightly acidic tea beverage consumed worldwide, but historically in China, Russia, and Germany. Kombucha is prepared by fermenting sweetened black tea preparations with a symbiotic culture of yeasts and bacteria. Potential health effects have created an increased interest in Kombucha. Yet, only a few research studies have shown that Kombucha has in vitro antimicrobial activity and enhances sleep and pain thresholds in rats. Furthermore, Kombucha consumption has proven to be harmful in several documented instances.

Scanning Electron Microscopic Study of In Vitro Toxicity of Ethylene Oxide Sterilized Bone Repair Materials.

DTIC Science & Technology

1988-08-15

16. SUPPLEMENTARY NOTATION To be published in J. of Oral Implantology 17. COSATI CODES 18. SUBJECT TERMS (Continue on reverse if necessary and identify...of Pathology% Physiologyt and Microbiology§ U.S. Army Institute of Dental Research Walter Reed Army Medical Center Washington.D.C. 20307-5300...Correspondence to Col. Theodore Zislis U.S. Army Institute of Dental Research Walter Reed Army Medical Center Washington, D.C. 20307-53C0 Tel. (301) 677-4915

The Clinically Tested Gardos Channel Inhibitor Senicapoc Exhibits Antimalarial Activity.

PubMed

Tubman, Venée N; Mejia, Pedro; Shmukler, Boris E; Bei, Amy K; Alper, Seth L; Mitchell, James R; Brugnara, Carlo; Duraisingh, Manoj T

2016-01-01

Senicapoc, a Gardos channel inhibitor, prevented erythrocyte dehydration in clinical trials of patients with sickle cell disease. We tested the hypothesis that senicapoc-induced blockade of the Gardos channel inhibits Plasmodium growth. Senicapoc inhibited in vitro growth of human and primate plasmodia during the clinical blood stage. Senicapoc treatment suppressed P. yoelii parasitemia in vivo in C57BL/6 mice. The reassuring safety and biochemical profile of senicapoc encourage its use in antimalarial development. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

In Vitro Susceptibility of Neisseria gonorrhoeae Strains to Mupirocin, an Antibiotic Reformulated for Parenteral Administration in Nanoliposomes.

PubMed

Cern, Ahuva; Connolly, Kristie L; Jerse, Ann E; Barenholz, Yechezkel

2018-04-01

Neisseria gonorrhoeae is an urgent antibiotic-resistant threat. This study determined the MICs of mupirocin to be 0.0039 to 0.0625 μg/ml for 94 N. gonorrhoeae strains. Cross-resistance with other antibiotics was not detected. Mupirocin, which is currently limited to topical administration, demonstrated activity by injection when delivered in nanoliposomes. The nanoliposomal formulation of mupirocin is a potential treatment for drug-resistant N. gonorrhoeae . Copyright © 2018 American Society for Microbiology.

In vitro evaluation of apical extrusion of bacteria following use of new rotary instrumentation system.

PubMed

Mohammadi, Zahed

2009-04-01

The aim of this study was to evaluate the number of bacteria extruded apically from extracted teeth ex vivo after canal instrumentation using two engine-driven nickel-titanium instruments (Flex Master and V-Taper). Seventy extracted maxillary central incisor teeth were used. After preparing access cavities, root canals were contaminated with a suspension of Enterococcus faecalis, then dried. The contaminated roots were divided into two experimental groups of 30 teeth each and one control group of 10 teeth. Bacteria extruded from the apical foramen during instrumentation were collected into vials. The microbiological samples from the vials were incubated in culture media for 24 hours. Colonies of bacteria were counted, and the results were given as number of colony-forming units. The data obtained were analyzed using the Kruskal-Wallis one-way analysis of variance and Mann-Whitney U-tests, with alpha = 0.05 as the level for statistical significance. Results showed that there was no significant difference as to the number of extruded bacteria between the two engine-driven systems (P > 0.05). Both engine-driven nickel-titanium systems extruded bacteria through the apical foramen.

Swab or biopsy samples for bioburden testing of allograft musculoskeletal tissue?

PubMed

Varettas, Kerry

2014-12-01

Swab and biopsy samples of allograft musculoskeletal tissue are most commonly collected by tissue banks for bacterial and fungal bioburden testing. An in vitro study was performed using the National Committee for Clinical Laboratory Standards standard 'Quality control of microbiological transport systems' (2003) to validate and evaluate the recovery of six challenge organisms from swab and biopsy samples of allograft musculoskeletal tissue. On average, 8.4 to >100 and 7.2 to >100 % of the inoculum was recovered from swab and biopsy samples respectively. A retrospective review of donor episodes was also performed, consisting of paired swab and biopsy samples received in this laboratory during the period 2001-2012. Samples of allograft femoral heads were collected from living donors during hip operations. From the 3,859 donor episodes received, 21 paired swab and biopsy samples each recovered an isolate, 247 swab samples only and 79 biopsy samples only were culture positive. Low numbers of challenge organisms were recovered from inoculated swab and biopsy samples in the in vitro study and validated their use for bioburden testing of allograft musculoskeletal tissue. Skin commensals were the most common group of organisms isolated during a 12-year retrospective review of paired swab and biopsy samples from living donor allograft femoral heads. Paired swab and biopsy samples are a suitable representative sample of allograft musculoskeletal tissue for bioburden testing.

Inactivation of Bacillus cereus by Na-chlorophyllin-based photosensitization on the surface of packaging.

PubMed

Luksiene, Z; Buchovec, I; Paskeviciute, E

2010-11-01

This study was focused on the possibility to inactivate food-borne pathogen Bacillus cereus by Na-chlorophyllin (Na-Chl)-based photosensitization in vitro and after attachment to the surface of packaging material. Bacillus cereus in vitro or attached to the packaging was incubated with Na-Chl (7·5×10(-8) to 7·5×10(-5) mol l(-1) ) for 2-60min in phosphate buffer saline. Photosensitization was performed by illuminating cells under a light with a λ of 400nm and an energy density of 20mW cm(-2) . The illumination time varied 0-5min and subsequently the total energy dose was 0-6J cm(-2) . The results show that B. cereus vegetative cells in vitro or attached to the surface of packaging after incubation with 7·5×10(-7) mol l(-1) Na-Chl and following illumination were inactivated by 7log. The photoinactivation of B. cereus spores in vitro by 4log required higher (7·5×10(-6) mol l(-1) ) Na-Chl concentration. Decontamination of packaging material from attached spores by photosensitization reached 5log at 7·5×10(-5) mol l(-1) Na-Chl concentration. Comparative analysis of different packaging decontamination treatments indicates that washing with water can diminish pathogen population on the surface by <1log, 100ppm Na-hypochlorite reduces the pathogens about 1·7log and 200ppm Na-hypochlorite by 2·2log. Meanwhile, Na-Chl-based photosensitization reduces bacteria on the surface by 4·2 orders of magnitude. Food-borne pathogen B. cereus could be effectively inactivated (7log) by Na-Chl-based photosensitization in vitro and on the surface of packaging material. Spores are more resistant than vegetative cells to photosensitization-based inactivation. Comparison of different surface decontamination treatments indicates that Na-Chl-based photosensitization is much more effective antibacterial tool than washing with water or 200ppm Na-hypochlorite. Our data support the idea that Na-Chl-based photosensitization has great potential for future application as an environment-friendly, nonthermal surface decontamination technique. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.

Impact of the introduction of an automated microbiologic system on the clinical outcomes of bloodstream infections caused by Enterobacteriaceae strains.

PubMed

Callefi, Luciana Azevedo; Medeiros, Eduardo Alexandrino Servolo de; Furtado, Guilherme Henrique Campos

2013-01-01

Enterobacteriaceae strains are a leading cause of bloodstream infections (BSI). The aim of this study is to assess differences in clinical outcomes of patients with BSI caused by Enterobacteriaceae strains before and after introduction of an automated microbiologic system by the microbiology laboratory. We conducted a retrospective cohort study aimed to evaluate the impact of the introduction of an automated microbiologic system (Phoenix(tm) automated microbiology system, Becton, Dickinson and Company (BD) - Diagnostic Systems, Sparks, MD, USA) on the outcomes of BSIs caused by Enterobacteriaceae strains. The study was undertaken at Hospital São Paulo, a 750-bed teaching hospital in São Paulo, Brazil. Patients with BSI caused by Enterobacteriaceae strains before the introduction of the automated system were compared with patients with BSI caused by the same pathogens after the introduction of the automated system with regard to treatment adequacy, clinical cure/improvement and 14- and 28-day mortality rates. We evaluated 90 and 106 patients in the non-automated and automated testing periods, respectively. The most prevalent species in both periods were Klebsiella spp. and Proteus spp. Clinical cure/improvement occurred in 70% and 67.9% in non-automated and automated period, respectively (p = 0.75). 14-day mortality rates were 22.2% and 30% (p = 0.94) and 28-day mortality rates were 24.5% and 40.5% (p = 0.12). There were no significant differences between the two testing periods with regard to treatment adequacy, clinical cure/improvement and 14- and 28-day mortality rates. Introduction of the BD Phoenix(tm) automated microbiology system did not impact the clinical outcomes of BSIs caused by Enterobacteriaceae strains in our setting.

Microbiological assay of the Marshall Space Flight Center neutral buoyancy simulator

NASA Technical Reports Server (NTRS)

Beyerle, F. J.

1973-01-01

A neutral buoyancy simulator tank system is described in terms of microbiological and medical safety for astronauts. The system was designed to simulate a gravity-free state for evaluation of orbital operations in a microorganism-free environment. Methods for the identification and elimination of specific microorganisms are dealt with as measures for a pure system of space environment simulation.

Clinical Investigation Program Annual Progress Report

DTIC Science & Technology

1989-09-30

initiatives for the study of relatedness of bacterial and HLA antigens as they influence autoimmune diseases. Microbiology Service - FY 89 An in-house...1030 87/103 0 Identification of Those at Risk for Osteoporotic Hip Fractures, by an Noninvasive Measurement (P) (PR)... 105 87/104 0 SWOG 8600 - A...233 82/302 0 The Evaluation of Recently Introduced, Commercially Available Clinical Microbiology Products for Possible

Integration of microbiology and infectious disease teaching courses in an interdisciplinary training programme (Master level) centred on the 'One world, one health' WHO concept.

PubMed

Eveillard, Matthieu; Ruvoen, Nathalie; Lepelletier, Didier; Fradet, Stéphanie; Couvreur, Sébastien; Krempf, Michel; Magras, Catherine

2016-05-01

This report describes the integration of the microbiology and infectious diseases teaching courses in an international Master's level interdisciplinary programme based on the 'One world, one health' WHO concept, and reports the students and teachers' evaluation related to their feelings of about this innovative programme. The integration was evaluated by recording the positioning of these two topics in the five teaching units constituting the programme, and by identifying their contribution in the interactions between the different teaching units. The satisfaction of students was assessed by a quantitative survey, whereas the feelings of students and teachers were assessed by interviews. The study demonstrated that microbiology and infectious diseases were widely involved in interactions between the teaching units, constituting a kind of cement for the programme. The students assigned a mean score of 3.7 to the topics dealing with microbiology and infectious diseases. According to the qualitative data, students and teachers considered that the interdisciplinary approach provided new insights but reported problems of communication, probably inherent to the multiculturalism of the class. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

In Vitro Activity of Delafloxacin against Clinical Neisseria gonorrhoeae Isolates and Selection of Gonococcal Delafloxacin Resistance.

PubMed

Soge, Olusegun O; Salipante, Stephen J; No, David; Duffy, Erin; Roberts, Marilyn C

2016-05-01

We evaluated the in vitro activity of delafloxacin against a panel of 117 Neisseria gonorrhoeae strains, including 110 clinical isolates collected from 2012 to 2015 and seven reference strains, compared with the activities of seven antimicrobials currently or previously recommended for treatment of gonorrhea. We examined the potential for delafloxacin to select for resistant mutants in ciprofloxacin-susceptible and ciprofloxacin-resistant N. gonorrhoeae We characterized mutations in the gyrA, gyrB, parC, and parE genes and the multidrug-resistant efflux pumps (MtrC-MtrD-MtrE and NorM) by PCR and sequencing and by whole-genome sequencing. The MIC50, MIC90, and MIC ranges of delafloxacin were 0.06 μg/ml, 0.125 μg/ml, and ≤0.001 to 0.25 μg/ml, respectively. The frequency of spontaneous mutation ranged from 10(-7) to <10(-9) The multistep delafloxacin resistance selection of 30 daily passages resulted in stable resistant mutants. There was no obvious cross-resistance to nonfluoroquinolone comparator antimicrobials. A mutant with reduced susceptibility to ciprofloxacin (MIC, 0.25 μg/ml) obtained from the ciprofloxacin-susceptible parental strain had a novel Ser91Tyr alteration in the gyrA gene. We also identified new mutations in the gyrA and/or parC and parE genes and the multidrug-resistant efflux pumps (MtrC-MtrD-MtrE and NorM) of two mutant strains with elevated delafloxacin MICs of 1 μg/ml. Although delafloxacin exhibited potent in vitro activity against N. gonorrhoeae isolates and reference strains with diverse antimicrobial resistance profiles and demonstrated a low tendency to select for spontaneous mutants, it is important to establish the correlation between these excellent in vitro data and treatment outcomes through appropriate randomized controlled clinical trials. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Comparative phytochemical analysis and antibacterial efficacy of in vitro and in vivo extracts from East Indian sandalwood tree (Santalum album L.).

PubMed

Misra, B B; Dey, S

2012-12-01

Sandalwood oil has been found in numerous therapeutic applications in traditional medicines such as Chinese traditional medicine and Ayurveda. However, there are no comparative accounts available in the literature that focused on in vitro and in vivo tree sample-derived extracts. Combined dichloromethane and methanol extracts were obtained from in vitro samples, that is, callus, somatic embryo and seedlings, and in vivo from leaves of non-oil-yielding young and oil-yielding matured trees. Phytochemical evaluation of the extracts reveals that the tree is rich in terpenoids, saponin, phenolics and tannins. The antibacterial properties of the five extracts were compared with sandalwood oil by screening against nine Gram-negative and five Gram-positive bacterial strains by disc diffusion, agar spot and TLC bioautography methods. Minimum inhibitory concentration (MIC) for sandalwood oil was determined to be in the range of 0·078-5 μg ml(-1) for most of the test micro-organisms screened. Bioautography results indicated the presence of potential antimicrobial constituents in somatic embryo extracts and sandalwood oil. Among the extracts screened, the somatic embryo extracts showed the strongest antibacterial activity comparable only with sandalwood oil and matured tree leaves' extract. The findings presented here also suggest that apart from sandalwood oil, other parts of this tree across developmental stages are also enriched with antibacterial principles. This study constitutes the first systematic investigation on phytochemical composition and antimicrobial efficacy of sandalwood tree across in vitro and in vivo developmental stages screened against thirteen bacterial strains by four methods. Using a battery of antimicrobial assay techniques, it is possible to follow the differential bioactive metabolic richness of plant parts, to decipher, for example comparable efficacy of somatic embryo extracts and sandalwood oil. © 2012 The Society for Applied Microbiology.

In vitro and in vivo activities of the nitroimidazole TBA-354 against Mycobacterium tuberculosis.

PubMed

Upton, A M; Cho, S; Yang, T J; Kim, Y; Wang, Y; Lu, Y; Wang, B; Xu, J; Mdluli, K; Ma, Z; Franzblau, S G

2015-01-01

Nitroimidazoles are a promising new class of antitubercular agents. The nitroimidazo-oxazole delamanid (OPC-67683, Deltyba) is in phase III trials for the treatment of multidrug-resistant tuberculosis, while the nitroimidazo-oxazine PA-824 is entering phase III for drug-sensitive and drug-resistant tuberculosis. TBA-354 (SN31354[(S)-2-nitro-6-((6-(4-trifluoromethoxy)phenyl)pyridine-3-yl)methoxy)-6,7-dihydro-5H-imidazo[2,1-b][1,3]oxazine]) is a pyridine-containing biaryl compound with exceptional efficacy against chronic murine tuberculosis and favorable bioavailability in preliminary rodent studies. It was selected as a potential next-generation antituberculosis nitroimidazole following an extensive medicinal chemistry effort. Here, we further evaluate the pharmacokinetic properties and activity of TBA-354 against Mycobacterium tuberculosis. TBA-354 is narrow spectrum and bactericidal in vitro against replicating and nonreplicating Mycobacterium tuberculosis, with potency similar to that of delamanid and greater than that of PA-824. The addition of serum protein or albumin does not significantly alter this activity. TBA-354 maintains activity against Mycobacterium tuberculosis H37Rv isogenic monoresistant strains and clinical drug-sensitive and drug-resistant isolates. Spontaneous resistant mutants appear at a frequency of 3 × 10(-7). In vitro studies and in vivo studies in mice confirm that TBA-354 has high bioavailability and a long elimination half-life. In vitro studies suggest a low risk of drug-drug interactions. Low-dose aerosol infection models of acute and chronic murine tuberculosis reveal time- and dose-dependent in vivo bactericidal activity that is at least as potent as that of delamanid and more potent than that of PA-824. Its superior potency and pharmacokinetic profile that predicts suitability for once-daily oral dosing suggest that TBA-354 be studied further for its potential as a next-generation nitroimidazole. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

[Microbiological and physicochemical evaluation of pasteurized beverages fortified with orange deodorized residues extracts].

PubMed

Moreno Alvarez, Mario José; Machado, Alexandra; Padrón, Arelis; García, David; Belén Camacho, Douglas Rafael

2004-09-01

Microbiological and physicochemical parameters of pasteurized beverages conditioned with aqueous extracts from orange deodorized residues were evaluated. The fruits used were selected according to following criterion: homogenous maturity, without physical damage and absence of apparent chlorophyll. Orange peels were dried and transformed to flour. The juice was evaluated by means of these parameters: pH 3.90, degrees Brix 10, titrable acidity 0.33 g of citric acid/100 mL and total carotenoids 0.0078 mg/mL. Volatil compounds of the flour that may to cause bitterness were separated by means of two methods of deodorization: distillation in current of vapor and in autoclave to 121 degrees C; then, the flour was extracted with water (relation 1:50 p/v). Pasteurized citric beverages (orange juice) were elaborated adding the deodorized extracts. pH, degrees Brix, titrable acidity and total carotenoids showed no significant differences (P>0.05). Microbiological results were according to pasteurized products. Sensorial analysis by untrained panel showed no signiificant differences. In conclusion, the deodorant processes were effectives and permitted the inclusion of aquasoluble compounds as flavonoids with antioxidant activity.

In vitro effectiveness of anidulafungin against Candida sp. biofilms.

PubMed

Rosato, Antonio; Piarulli, Monica; Schiavone, Brigida Pia Immacolata; Catalano, Alessia; Carocci, Alessia; Carrieri, Antonio; Carone, Addolorata; Caggiano, Giuseppina; Franchini, Carlo; Corbo, Filomena; Montagna, Maria Teresa

2013-12-01

This study furnishes deeper insights to previous works on anidulafungin, demonstrating the potent activity against Candida strains planktonic cells and biofilms. Candida sp., associated with many biomaterial-related infections, give rise to infective pathologies typically associated with biofilm formation. We recently determined the in vitro antifungal activities of echinocandin anidulafungin in association with some antifungal drugs against some Candida strains in their planktonic states. A total of 11 Candida strains biofilms were tested in this study: six Candida albicans, three C. parapsilosis and two C. tropicalis. All yeast isolates and ATCC strains were stored at -20°C in glycerol stocks and were subcultured on antimicrobial agent-free Sabouraud dextrose agar plates. MIC endpoints were determined colorimetrically by using the indicator 2,3-bis(2-methoxy-4-nitro-5-sulphophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) with menadione as electron-coupling agent. The activity of anidulafungin was assessed using in vitro microbiological model relevant for clinical practice. Anidulafungin showed a strong activity in vitro against both planktonic and biofilms cells, and our study confirms that high anidulafungin concentrations might establish paradoxical growth effect in C. albicans and C. tropicalis biofilms.

Utility of Gram stain for the microbiological analysis of burn wound surfaces.

PubMed

Elsayed, Sameer; Gregson, Daniel B; Lloyd, Tracie; Crichton, Marilyn; Church, Deirdre L

2003-11-01

Surface swab cultures have attracted attention as a potential alternative to biopsy histology or quantitative culture methods for microbiological burn wound monitoring. To our knowledge, the utility of adding a Gram-stained slide in this context has not been evaluated previously. To determine the degree of correlation of Gram stain with culture for the microbiological analysis of burn wound surfaces. Prospective laboratory analysis. Urban health region/centralized diagnostic microbiology laboratory. Burn patients hospitalized in any Calgary Health Region burn center from November 2000 to September 2001. Gram stain plus culture of burn wound surface swab specimens obtained during routine dressing changes or based on clinical signs of infection. Degree of correlation (complete, high, partial, none), including weighted kappa statistic (kappa(w)), of Gram stain with culture based on quantitative microscopy and degree of culture growth. A total of 375 specimens from 50 burn patients were evaluated. Of these, 239 were negative by culture and Gram stain, 7 were positive by Gram stain only, 89 were positive by culture only, and 40 were positive by both methods. The degree of complete, high, partial, and no correlation of Gram stain with culture was 70.9% (266/375), 1.1% (4/375), 2.4% (9/375), and 25.6% (96/375), respectively. The degree of correlation for all 375 specimens, as expressed by the weighted kappa statistic, was found to be fair (kappa(w) = 0.32).Conclusion.-The Gram stain is not suitable for the microbiological analysis of burn wound surfaces.

Novel Bacterial Topoisomerase Inhibitors with Potent Broad-Spectrum Activity against Drug-Resistant Bacteria.

PubMed

Charrier, Cédric; Salisbury, Anne-Marie; Savage, Victoria J; Duffy, Thomas; Moyo, Emmanuel; Chaffer-Malam, Nathan; Ooi, Nicola; Newman, Rebecca; Cheung, Jonathan; Metzger, Richard; McGarry, David; Pichowicz, Mark; Sigerson, Ralph; Cooper, Ian R; Nelson, Gary; Butler, Hayley S; Craighead, Mark; Ratcliffe, Andrew J; Best, Stuart A; Stokes, Neil R

2017-05-01

The novel bacterial topoisomerase inhibitor class is an investigational type of antibacterial inhibitor of DNA gyrase and topoisomerase IV that does not have cross-resistance with the quinolones. Here, we report the evaluation of the in vitro properties of a new series of this type of small molecule. Exemplar compounds selectively and potently inhibited the catalytic activities of Escherichia coli DNA gyrase and topoisomerase IV but did not block the DNA breakage-reunion step. Compounds showed broad-spectrum inhibitory activity against a wide range of Gram-positive and Gram-negative pathogens, including biodefence microorganisms and Mycobacterium tuberculosis No cross-resistance with fluoroquinolone-resistant Staphylococcus aureus and E. coli isolates was observed. Measured MIC 90 values were 4 and 8 μg/ml against a panel of contemporary multidrug-resistant isolates of Acinetobacter baumannii and E. coli , respectively. In addition, representative compounds exhibited greater antibacterial potency than the quinolones against obligate anaerobic species. Spontaneous mutation rates were low, with frequencies of resistance typically <10 -8 against E. coli and A. baumannii at concentrations equivalent to 4-fold the MIC. Compound-resistant E. coli mutants that were isolated following serial passage were characterized by whole-genome sequencing and carried a single Arg38Leu amino acid substitution in the GyrA subunit of DNA gyrase. Preliminary in vitro safety data indicate that the series shows a promising therapeutic index and potential for low human ether-a-go-go-related gene (hERG) inhibition (50% inhibitory concentration [IC 50 ], >100 μM). In summary, the compounds' distinct mechanism of action relative to the fluoroquinolones, whole-cell potency, low potential for resistance development, and favorable in vitro safety profile warrant their continued investigation as potential broad-spectrum antibacterial agents. Copyright © 2017 American Society for Microbiology.

Intravaginal boric acid: is it an alternative therapeutic option for vaginal trichomoniasis?

PubMed

Thorley, Nicola; Ross, Jonathan

2017-12-09

Trichomoniasis, caused by Trichomonas vaginalis (TV), is the most common curable sexually transmitted infection worldwide. Current guidance in the UK is to treat TV with a nitroimidazole antibiotic. The high prevalence of TV, high rate of antibiotic resistance and limited tolerability to nitroimidazoles suggest that alternative treatment regimens are needed. Intravaginal boric acid (BA) has been used safely for the treatment of candida vulvovaginitis and bacterial vaginosis, and in vitro studies suggest BA is active against TV. We review the evidence for the efficacy of BA in patients with TV. MEDLINE, EMBASE, CINAHL, AMED, HMIC and BNI and Grey literature databases, The Cochrane Library, Trial Registers, conference abstracts and proceedings were searched. Inclusion criteria were women aged 16 years or over with microbiological confirmation of TV infection and using BA as treatment. There were no restrictions on language, publication date or study design. The in vitro evidence for BA activity against TV was also reviewed. No randomised controlled trials or case series were found. Four case reports demonstrated TV clearance with BA using a variety of dose regimens (dose 600 mg alternate nights to 600 mg two times per day; duration 1-5 months). In vitro studies suggest that BA has activity against TV which is independent of its effect on pH. Further evaluation of BA for the treatment of uncomplicated TV is required, but it may be useful when therapeutic options are limited. If shown to be safe and effective, intravaginal BA might provide a well-tolerated alternative anti-infective treatment which reduces community exposure to systemic antibiotics. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Antimalarial Activity of Small-Molecule Benzothiazole Hydrazones.

PubMed

Sarkar, Souvik; Siddiqui, Asim A; Saha, Shubhra J; De, Rudranil; Mazumder, Somnath; Banerjee, Chinmoy; Iqbal, Mohd S; Nag, Shiladitya; Adhikari, Susanta; Bandyopadhyay, Uday

2016-07-01

We synthesized a new series of conjugated hydrazones that were found to be active against malaria parasite in vitro, as well as in vivo in a murine model. These hydrazones concentration-dependently chelated free iron and offered antimalarial activity. Upon screening of the synthesized hydrazones, compound 5f was found to be the most active iron chelator, as well as antiplasmodial. Compound 5f also interacted with free heme (KD [equilibrium dissociation constant] = 1.17 ± 0.8 μM), an iron-containing tetrapyrrole released after hemoglobin digestion by the parasite, and inhibited heme polymerization by parasite lysate. Structure-activity relationship studies indicated that a nitrogen- and sulfur-substituted five-membered aromatic ring present within the benzothiazole hydrazones might be responsible for their antimalarial activity. The dose-dependent antimalarial and heme polymerization inhibitory activities of the lead compound 5f were further validated by following [(3)H]hypoxanthine incorporation and hemozoin formation in parasite, respectively. It is worth mentioning that compound 5f exhibited antiplasmodial activity in vitro against a chloroquine/pyrimethamine-resistant strain of Plasmodium falciparum (K1). We also evaluated in vivo antimalarial activity of compound 5f in a murine model where a lethal multiple-drug-resistant strain of Plasmodium yoelii was used to infect Swiss albino mice. Compound 5f significantly suppressed the growth of parasite, and the infected mice experienced longer life spans upon treatment with this compound. During in vitro and in vivo toxicity assays, compound 5f showed minimal alteration in biochemical and hematological parameters compared to control. In conclusion, we identified a new class of hydrazone with therapeutic potential against malaria. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Probiotic bacteria inhibit the bovine respiratory pathogen Mannheimia haemolytica serotype 1 in vitro.

PubMed

Amat, S; Subramanian, S; Timsit, E; Alexander, T W

2017-05-01

This study evaluated the potential of probiotic bacteria to inhibit growth and cell adhesion of the bovine respiratory pathogen Mannheimia haemoltyica serotype 1. The inhibitory effects of nine probiotic strains (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus helveticus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactococcus lactis, Streptococcus thermophilus and two Paenibacillus polymyxa strains) against M. haemolytica were evaluated using a spot-on-lawn method. Probiotic strains were then tested for their adherence to bovine bronchial epithelial (BBE) cells and the ability to displace and compete against M. haemolytica on BBE. Except for S. thermophilus, all probiotic strains inhibited the growth of M. haemolytica, with zones of inhibition ranging between 12 and 19 mm. Lactobacillus strains and Lactococcus lactis displayed greater (P < 0·05) BBE adhesion compared with M. heamolytica (8·3%) and other probiotics (<2·2%). Strains of P. polymyxa and L. acidophilus caused the greatest reduction in M. haemolytica adherence, through both displacement and competition, compared with other probiotics. The results of this study suggest that probiotics may have the potential to colonize the bovine respiratory tract, and exert antagonistic effects against M. haemolytica serotype 1. A common method to control bovine respiratory disease (BRD) in feedlots is through mass medication with antibiotics upon cattle entry (i.e. metaphylaxis). Increasingly, antimicrobial resistance in BRD bacterial pathogens has been observed in feedlots, which may have important implications for cattle health. In this study, probiotic strains were shown to adhere to bovine respiratory cells and inhibit the BRD pathogen M. haemolytica serotype 1 through competition and displacement. Probiotics may therefore offer a mitigation strategy to reduce BRD bacterial pathogens, in place of metaphylactic antimicrobials. © 2017 Her Majesty the Queen in Right of Canada Letters in Applied Microbiology © 2017 The Society for Applied Microbiology Reproduced with the permission of the Minister of Agriculture and Agri-Food Canada.

Differential effects of rice bran cultivars to limit Salmonella Typhimurium in chicken cecal in vitro incubations and impact on the cecal microbiome and metabolome.

PubMed

Rubinelli, Peter M; Kim, Sun Ae; Park, Si Hong; Roto, Stephanie M; Nealon, Nora Jean; Ryan, Elizabeth P; Ricke, Steven C

2017-01-01

In this study, rice brans from different cultivars (Calrose, Jasmine, and Red Wells) were assessed for their ability to inhibit Salmonella enterica serovar Typhimurium using an in vitro mixed anaerobic culture system containing cecal microbiota obtained from broilers of different ages. Salmonella Typhimurium was added to controls (feed only, cecal only, and feed + cecal material) and treatments (feed + cecal + different rice brans) and S. Typhimurium populations were enumerated at 0, 24, and 48 h. Two experimental conditions were applied 1) unadapted condition in which S. Typhimurium was added at the beginning of the culture incubation and 2) adapted condition in which S. Typhimurium was added after a 24 hour pre-incubation of the cecal bacteria with the feed and/or rice bran. Among the three rice brans, only Calrose exhibited a rapid inhibition of S. Typhimurium, which decreased to undetectable levels after 24 h under the adapted incubation. Changes in microbiological composition and metabolites by addition of Calrose bran were also investigated with an Illumina MiSeq platform and gas chromatography-mass spectrometry, respectively. Addition of Calrose bran resulted in significant changes including decreased Firmicutes phylum abundance and an increased number of metabolites associated with fatty acid metabolism. In summary, it appears that rice bran from specific rice cultivars may be effective as a means to reduce Salmonella in the chicken ceca. In addition, Calrose rice bran inclusion leads to changes in cecal microbiological composition and metabolite profile.

Bacterial keratitis: a prospective clinical and microbiological study

PubMed Central

Schaefer, F.; Bruttin, O.; Zografos, L.; Guex-Crosier, Y.

2001-01-01

AIM—To define the clinical and microbiological profile of bacterial keratitis at the Jules Gonin Eye Hospital and to test the in vitro bacterial resistance.
METHODS—Patients presenting with bacterial keratitis were prospectively followed; clinical features (age, risk factors, visual acuity) and response to therapy were analysed. Bacteriological profile was determined and the sensitivity/resistance of isolated strains were tested towards 12 ocular antibiotics (NCCLS disc diffusion test).
RESULTS—85 consecutive patients (mean age 44.3 (SD 20.7) years) were prospectively enrolled from 1 March 1997 to 30 November 1998. The following risk factors were identified: contact lens wear, 36%; blepharitis, 21%; trauma, 20%; xerophthalmia, 15%; keratopathies, 8%; and eyelid abnormalities, 6%. The most commonly isolated bacteria were Staphylococcus epidermidis, 40%; Staphylococcus aureus, 22%; Streptococcus pneumoniae, 8%; others Streptococcus species, 5%; Pseudomonas, 9%; Moraxella and Serratia marcescens, 5% each; Bacillus, Corynebacterium, Alcaligenes xyloxidans, Morganella morganii, and Haemophilus influenza, 1% each. 1-15% of strains were resistant to fluoroquinolones, 13-22% to aminoglycosides, 37% to cefazolin, 18% to chloramphenicol, 54% to polymyxin B, 51% to fusidic acid, and 45% to bacitracin. Five of the 85 patients (5.8%) had a poor clinical outcome with a visual loss of one or more lines of visual acuity.
CONCLUSION—Fluoroquinolones appear to be the therapy of choice for bacterial keratitis, but, based upon these in vitro studies, some strains may be resistant.

 PMID:11423460

Recent publications in medical microbiology and immunology: a retrospective.

PubMed

Doerr, H W; Cinatl, J

2012-02-01

A look back is done to some clinical and basic research activities recently published in medical microbiology and immunology. The review covers clinical experiences and in vitro experiments to understand the emergency, pathogenicity, epidemic spread, and vaccine-based prevention of avian and swine-origin flu. Some new developments and concepts in diagnosis, (molecular) epidemiology, and therapy of AIDS, viral hepatitis C, and herpesvirus-associated diseases are outlined. Regulation of immune system has been discussed in a special issue 2010 including some aspects of CNS affections (measles). Mycobacterial infection and its prevention by modern recombinant vaccines have reached new interest, as well as new concepts of vaccination and prophylaxis against several other bacteria. Adaptation to host niches enables immune escape (example brucella) and determines virulence (example N. meningitidis). Chlamydia pneumoniae, previously considered to trigger atherosclerosis, is hypothetically associated to Alzheimer disease, while CMV, another putative trigger of atherosclerosis, gains evidence of oncomodulation in CNS tumor diseases. In terms of globalization, exotic virus infections are increasingly imported from southern countries.

An Evaluation of Computer-based Instruction in Microbiology.

ERIC Educational Resources Information Center

Merkel, Susan M.; Walman, Laura B.; Leventhal, Jeremy S.

2000-01-01

Discusses whether computer-based instructional materials improve student learning. Evaluates a computer-based hypermedia tutorial that was delivered over a web site. (Contains 24 references.) (Author/YDS)

Microbiological Evaluation of Aviation Fuel Storage, Dispensing and Aircraft Systems

DTIC Science & Technology

1974-11-01

Penicillium sp . were the most consistently observed fungal contaminants. These microbiological analyses of the 26...unidentified 15 > 300 bacterial colonies 16 1 Alternaria sp . 17 1 Epicoccum sp . 18 1 Cytosporella U. 19 8 Penicillium M., 3 Cladosporium sp ., 1...Curvularia sp ., 1 Zygodesmus sp ., several bacteria colonies 20 5 Penicillium sp ., 3 Cladosporium sp ., 2 Curvularia §p., 1 Amerosporium sp ., 1

Transforming a sequence of microbiology courses using student profile data.

PubMed

Buxeda, R J; Moore, D A

2000-05-01

A study was performed in the General Microbiology and Industrial Microbiology courses to increase research awareness at an early stage of the educational process and to establish collaboration between students in an Industrial Microbiology program and industry. In both courses, the professor helped students determine their learning styles and then used these data to design activities in order to accomplish the above objectives. In both the treatment and the control sections, students learned about strategies to optimize learning based on their learning styles. A cooperative learning format was introduced to promote active learning and team-building skills. The diverse learning styles data profile was used by students during cooperative learning activities for effective team integration. In the General Microbiology course, a mentor-mentee structure was introduced to expose students to research in microbiology by visiting research facilities on campus. This structure was an addition to the regular curriculum, which meets American Society for Microbiology curriculum recommendations. The results suggest an increase in interest in research by students. In the Industrial Microbiology course, a strategy was introduced to establish collaboration with industry in which students visit the workplace and identify microbial processes, microbiologist roles, and skills needed by microbiologists. Evaluation of these topics using pre- and posttest data indicates a significant increase in acquired knowledge relevant to daily workplace environments with the reformed course. In both courses, students gain information early in their academic experience to help them consider participation in research experiences while providing them with real-world experience toward the end of their academic careers, when they see the need for it.

Experimental design and modelling approach to evaluate efficacy of β-lactam/β-lactamase inhibitor combinations.

PubMed

Sy, S K B; Derendorf, H

2017-07-29

A β-lactamase inhibitor (BLI) confers susceptibility of β-lactamase-expressing multidrug resistant (MDR) organisms to the partnering β-lactam (BL). To discuss the experimental design and modelling strategies for two-drug combinations, using ceftazidime- and aztreonam-avibactam combinations, as examples. The information came from several publications on avibactam in vitro time-kill studies and corresponding pharmacodynamic models. The experimental design to optimally gather crucial information from constant-concentration time-kill studies is to use an agile matrix of two-drug concentration combinations that cover 0.25- to 4-fold BL minimum inhibitory concentration (MIC) relative to the BLI concentrations to be tested against the particular isolate. This shifting agile design can save substantial costs and resources, without sacrificing crucial information needed for model development. The complex synergistic BL/BLI interaction is quantitatively explored using a semi-mechanistic pharmacokinetic-pharmacodynamic (PK/PD) mathematical model that accounts for antimicrobial activities in the combination, bacteria-mediated BL degradation and inhibition of BL degradation by BLI. A predictive mathematical formulation for the two-drug killing effects preserves the correlation between the model-derived EC 50 of BL and the BL MIC. The predictive value of PK/PD model is evaluated against external data that were not used for model development, including but not limited to in vitro hollow fibre and in vivo murine infection models. As a framework for translational predictions, the goal of this modelling strategy is to significantly decrease the decision-making time by running clinical trial simulations with MIC-substituted EC 50 function for isolates of comparable susceptibility through established correlation between BL MIC and EC 50 values. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Comparative evaluation of calcium hypochlorite and sodium hypochlorite associated with passive ultrasonic irrigation on antimicrobial activity of a root canal system infected with Enterococcus faecalis: an in vitro study.

PubMed

de Almeida, Ana Paula; Souza, Matheus Albino; Miyagaki, Daniela Cristina; Dal Bello, Yuri; Cecchin, Doglas; Farina, Ana Paula

2014-12-01

The purpose of this study was to compare in vitro the effectiveness of calcium hypochlorite (Ca[OCl]2) and sodium hypochlorite (NaOCl) associated with passive ultrasonic irrigation in root canals of bovine teeth infected with Enterococcus faecalis. The root canals of 60 single-rooted bovine extracted teeth were enlarged up to a file 45, autoclaved, inoculated with Enterococcus faecalis, and incubated for 30 days. The samples were divided into 6 groups (n = 10) according to the protocol for decontamination: G1: no treatment; G2: distilled water; G3: 2.5% NaOCl; G4: 2.5% Ca(OCl)2; G5: 2.5% NaOCl with ultrasonic activation; and G6: 2.5% Ca(OCl)2 with ultrasonic activation (US). Microbiological testing (colony-forming unit [CFU] counting) was performed to evaluate and show, respectively, the effectiveness of the proposed treatments. Data were subjected to 1-way analysis of variance followed by the post hoc Tukey test (α = 0.05). Groups 1 and 2 showed the highest mean contamination (3.26 log10 CFU/mL and 2.69 log10 CFU/mL, respectively), which was statistically different from all other groups (P < .05). Group 6 (Ca[OCl]2 + US) showed the lowest mean contamination (1.00 log10 CFU/mL), with no statistically significant difference found in groups 3 (NaOCl), 4 (Ca[OCl]2), and 5 (NaOCl + US) (P < .05). Ca(OCl)2 as well as passive ultrasonic irrigation can aid in chemomechanical preparation, contributing in a significant way to the reduction of microbial content during root canal treatment. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Monitoring Anti-Pythium insidiosum IgG Antibodies and (1->3)-β-D-Glucan in Vascular Pythiosis.

PubMed

Worasilchai, Navaporn; Permpalung, Nitipong; Chongsathidkiet, Pakawat; Leelahavanichkul, Asada; Mendoza, Alberto Leonel; Palaga, Tanapat; Reantragoon, Rangsima; Finkelman, Malcolm; Sutcharitchan, Pranee; Chindamporn, Ariya

2018-05-30

Background: Despite aggressive treatment, vascular pythiosis has a mortality rate of 40%. This is due to delays in diagnosis and lack of effective monitoring tools. To overcome this drawback, serum beta-D-glucan (BG) and P. insidiosum specific antibody ( Pi -Ab) were examined as potential monitoring markers in vascular pythiosis. Methods: A prospective cohort study of vascular pythiosis patients was carried on during January 2010-July 2016. Clinical information and blood samples were collected and evaluated by the BG and Pi -Ab assays. Linear mixed effect models were used to compare BG and Pi -Ab levels. The in vitro susceptibility test was performed in all P. insidiosum isolates from culture positive cases. Results: A total of 50 patients were enrolled; 45 survived and 5 died during follow-up. The survivors had a significantly shorter time to medical care (p<0.0001) and a significantly shorter waiting time to the first surgery (p<0.0001). There were no differences in BG levels among the groups at diagnosis (p=0.33); however, BG levels among survivors were significantly lower than the deceased group at 0.5 months (p<0.0001) and became undetectable after 3 months. Survivors were able to maintain ELISA value (EV) of Pi -Ab above 8, whereas EV among deceased patients was less than 4. In vitro susceptibility results revealed no synergistic effects between itraconazole and terbinafine. Conclusions: This study showed that BG and Pi -Ab were potentially valuable markers to monitor the disease after treatment initiation. An unchanged BG level at 2 weeks after surgery should prompt an evaluation for residual disease. Copyright © 2018 American Society for Microbiology.

IMPACT OF MICROBIOLOGICAL CHANGES ON SPONTANEOUS BACTERIAL PERITONITIS IN THREE DIFFERENT PERIODS OVER 17 YEARS.

PubMed

Almeida, Paulo Roberto Lerias de; Leão, Gabriel Stefani; Gonçalves, Charlles David Gonçalves; Picon, Rafael Veiga; Tovo, Cristiane Valle

2018-01-01

Spontaneous bacterial peritonitis is a serious complication in cirrhotic patients, and changes in the microbiological characteristics reported in the last years are impacting the choice of antibiotic used for treatment. The aim of the present study is to evaluate the changes in the epidemiology and bacterial resistance of the germs causing spontaneous bacterial peritonitis over three different periods over 17 years. All cirrhotic patients with spontaneous bacterial peritonitis and positive culture of ascites fluid were retrospectively studied in a reference Hospital in Southern Brazil. Three periods were ramdomly evaluated: 1997-1998, 2002-2003 and 2014-2015. The most frequent infecting organisms and the sensitivity in vitro to antibiotics were registered. In the first period (1997-1998) there were 33 cases, the most common were: E. coli in 13 (36.11%), Staphylococcus coagulase-negative in 6 (16.66%), K. pneumoniae in 5 (13.88%), S. aureus in 4 (11.11%) and S. faecalis in 3 (8.33%). In the second period (2002-2003), there were 43 cases, the most frequent were: Staphylococus coagulase-negative in 16 (35.55%), S. aureus in 8 (17.77%), E. coli in 7 (15.55%) and K. pneumoniae in 3 (6.66%). In the third period (2014-2015) there were 58 cases (seven with two bacteria), the most frequent were: E. coli in 15 (23.1%), S. viridans in 12 (18.5%), K. pneumoniae in 10 (15.4%) and E. faecium 5 (7.7%). No one was using antibiotic prophylaxis. Considering all staphylococci, the prevalence increased to rates of the order of 50% in the second period, with a reduction in the third period evaluated. Likewise, the prevalence of resistant E. coli increased, reaching 14%. There was a modification of the bacterial population causing spontaneous bacterial peritonitis, with high frequency of gram-positive organisms, as well as an increase in the resistance to the traditionally recommended antibiotics. This study suggests a probable imminent inclusion of a drug against gram-positive organisms in the empiric treatment of spontaneous bacterial peritonitis.

In Vitro Antifungal Susceptibility Testing of Candida Isolates with the EUCAST Methodology, a New Method for ECOFF Determination.

PubMed

Meletiadis, J; Curfs-Breuker, I; Meis, J F; Mouton, J W

2017-04-01

The in vitro susceptibilities of 1,099 molecularly identified clinical Candida isolates against 8 antifungal drugs were determined using the EUCAST microdilution method. A new simple, objective, and mathematically solid method for determining epidemiological cutoff values (ECOFFs) was developed by derivatizing the MIC distribution and determining the derivatized ECOFF (dECOFF) as the highest MIC with the maximum second derivative. The dECOFFs were similar (95% agreement within 1 dilution) to the EUCAST ECOFFs. Overall, low non-wild-type/resistance rates were found. The highest rates were found for azoles with C. parapsilosis (2.7 to 9.8%), C. albicans (7%), and C. glabrata (1.7 to 2.3%) and for echinocandins with C. krusei (3.3%), C. albicans (1%), and C. tropicalis (1.7%). Copyright © 2017 American Society for Microbiology.

Evaluation of Iranian microbiology laboratories for identification of etiologic agents of bacterial meningitidis. Survey results of an external quality assessment scheme (EQAS) programme.

PubMed

Marandi, Farinaz Rashed; Rahbar, Mohammad; Sabourian, Roghieh; Saremi, Mahnaz

2010-01-01

To determine the ability of Iranian microbiology laboratories for identification and susceptibility testing of Streptococcus pneumoniae and Haemophilus influenzae as causative agents of bacterial meningitides. Two strains of bacteria including Haemophilus influenzae and Streptococcus pneumoniae as a common causative agents of meningitides were chosen and coded as strain number 1 and number 2. The strains were distributed among 679 microbiology laboratories. All laboratories were requested for identification of each unknown microorganism and susceptibility testing of S. pneumoniae against five commonly used antibiotics. Of 679 microbiology laboratories 310 (46%) laboratories participated in the survey and among these, 258 laboratories completely identified S. pneumoniae. About 85% laboratories produced correct susceptibility testing against oxacillin, erythromycin, tetracycline, and vancomycin. Of 310 received responses only 50 laboratories identified H. influenza correctly. The majority of the laboratories did not have the capacity to identification H. influenza. Microbiology laboratories in our country are qualified for identification and susceptibility testing of S. pneumoniae. However, majority of laboratories are not qualified for identification of H. influenzae.

Sterilization validation for medical devices at IRASM microbiological laboratory—Practical approaches

NASA Astrophysics Data System (ADS)

Trandafir, Laura; Alexandru, Mioara; Constantin, Mihai; Ioniţă, Anca; Zorilă, Florina; Moise, Valentin

2012-09-01

EN ISO 11137 established regulations for setting or substantiating the dose for achieving the desired sterility assurance level. The validation studies can be designed in particular for different types of products. Each product needs distinct protocols for bioburden determination and sterility testing. The Microbiological Laboratory from Irradiation Processing Center (IRASM) deals with different types of products, mainly for the VDmax25 method. When it comes to microbiological evaluation the most challenging was cotton gauze. A special situation for establishing the sterilization validation method appears in cases of cotton packed in large quantities. The VDmax25 method cannot be applied for items with average bioburden more than 1000 CFU/pack, irrespective of the weight of the package. This is a method limitation and implies increased costs for the manufacturer when choosing other methods. For microbiological tests, culture condition should be selected in both cases of the bioburden and sterility testing. Details about choosing criteria are given.

Black Stains: a microbiological analysis and a view on familiarity and susceptibility to tooth decay of patients in childhood.

PubMed

Tripodi, D; Martinelli, D; Pasini, M; Giuca, M R; D'Ercole, S

2016-12-01

Assess prevalence, familial predisposition and susceptibility to caries of Black Stains (BS). Evaluate the microbiological composition of BS, saliva and subgingival plaque. Sixty nine subjects with BS (test group) and 120 subjects without BS (control group) were analysed for oral status. For each BS-patient, a BS-deposit, 1 ml of saliva and subgingival plaque were collected and microbiologically analysed. Five deciduous teeth with BS were observed under SEM. This study showed a BS prevalence similar to that of the Mediterranean area and a familiality. The microbiological origin of BS was confirmed by SEM and culture method and the BS flora differ from that of supragingival plaque. Predominance in BS and saliva of Actinomycetes and the low salivary prevalence of S. mutans and L. acidophilus may be related with low caries incidence in BS patients. The high presence of Actinomyces spp can be a causative factor for BS.

Assessing Clinical Microbiology Practice Guidelines: American Society for Microbiology Ad Hoc Committee on Evidence-Based Laboratory Medicine Practice Guidelines Assessment.

PubMed

Nachamkin, Irving; Kirn, Thomas J; Westblade, Lars F; Humphries, Romney

2017-11-01

As part of the American Society for Microbiology (ASM) Evidence-Based Laboratory Medicine Practice Guidelines Committee of the Professional Practice Committee, an ad hoc committee was formed in 2014 to assess guidelines published by the committee using an assessment tool, Appraisal of Guidelines for Research Evaluation II (AGREE II). The AGREE II assessment helps reviewers determine whether published guidelines are robust, transparent, and clear in presenting practice recommendations in a standardized manner. Identifying strengths and weaknesses of practice guidelines by ad hoc assessments helps with improving future guidelines through the participation of key stakeholders. This minireview describes the development of the ad hoc committee and results from their review of several ASM best practices guidelines and a non-ASM practice guideline from the Emergency Nurses Association. Copyright © 2017 American Society for Microbiology.

[Indicators of water microbial pollution: problems and perspectives].

PubMed

Nusca, A; D'Alessandro, D; Funari, E

2008-01-01

Conventional indicators of fecal contamination provide a precious contribution in evaluating water microbiological quality. In recent years some important issues have sprung up which have risen doubts about their reliability and have suggested a revision of their function. In developed countries, where the law regarding water quality is very strict, there have been several outbreaks, even though conventional indicators of fecal pollution pointed an appropriate microbiological quality. These outbreaks have been imputed to new pathogenic microorganisms which are often characterized by a great resistance to disinfection treatments than conventional indicators. In order to obtain an appropriate microbiological quality of waters, various approaches have been started such as the Water Safety Plans by World Health Organization the revision of the functions of suitable indicators (of the water quality), the setting up of specific methods either for pathogen microorganisms and for a quick surveying of an inadequate microbiological water quality.

Milk kefir: nutritional, microbiological and health benefits.

PubMed

Rosa, Damiana D; Dias, Manoela M S; Grześkowiak, Łukasz M; Reis, Sandra A; Conceição, Lisiane L; Peluzio, Maria do Carmo G

2017-06-01

Kefir is fermented milk produced from grains that comprise a specific and complex mixture of bacteria and yeasts that live in a symbiotic association. The nutritional composition of kefir varies according to the milk composition, the microbiological composition of the grains used, the time/temperature of fermentation and storage conditions. Kefir originates from the Caucasus and Tibet. Recently, kefir has raised interest in the scientific community due to its numerous beneficial effects on health. Currently, several scientific studies have supported the health benefits of kefir, as reported historically as a probiotic drink with great potential in health promotion, as well as being a safe and inexpensive food, easily produced at home. Regular consumption of kefir has been associated with improved digestion and tolerance to lactose, antibacterial effect, hypocholesterolaemic effect, control of plasma glucose, anti-hypertensive effect, anti-inflammatory effect, antioxidant activity, anti-carcinogenic activity, anti-allergenic activity and healing effects. A large proportion of the studies that support these findings were conducted in vitro or in animal models. However, there is a need for systematic clinical trials to better understand the effects of regular use of kefir as part of a diet, and for their effect on preventing diseases. Thus, the present review focuses on the nutritional and microbiological composition of kefir and presents relevant findings associated with the beneficial effects of kefir on human and animal health.

Inadequate management of pregnancy-associated listeriosis: lessons from four case reports.

PubMed

Charlier, C; Goffinet, F; Azria, E; Leclercq, A; Lecuit, M

2014-03-01

Listeria monocytogenes infection during pregnancy can lead to dramatic fetal or neonatal outcomes. No clinical trial has evaluated treatment options, and retrospective studies of cases are therefore important to define optimal regimens. We report four cases of materno-neonatal listeriosis illustrating inadequate antimicrobial therapy management and discuss recommended treatment options. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

Data for methyl bromide decon testing

EPA Pesticide Factsheets

Spreadsheets containing data for recovery of spores from different materials. Data on the fumigation parameters are also included.This dataset is associated with the following publication:Wood , J., M. Wendling, W. Richter, A. Lastivka, and L. Mickelsen. Evaluation of the Efficacy of Methyl Bromide in the Decontamination of Building and Interior Materials Contaminated with Bacillus anthracis Spores. APPLIED AND ENVIRONMENTAL MICROBIOLOGY. American Society for Microbiology, Washington, DC, USA, 1-28, (2016).

Field Application of the Micro Biological Survey Method for a Simple and Effective Assessment of the Microbiological Quality of Water Sources in Developing Countries

PubMed Central

Arienzo, Alyexandra; Sobze, Martin Sanou; Wadoum, Raoul Emeric Guetiya; Losito, Francesca; Colizzi, Vittorio; Antonini, Giovanni

2015-01-01

According to the World Health Organization (WHO) guidelines, “safe drinking-water must not represent any significant risk to health over a lifetime of consumption, including different sensitivities that may occur between life stages”. Traditional methods of water analysis are usually complex, time consuming and require an appropriately equipped laboratory, specialized personnel and expensive instrumentation. The aim of this work was to apply an alternative method, the Micro Biological Survey (MBS), to analyse for contaminants in drinking water. Preliminary experiments were carried out to demonstrate the linearity and accuracy of the MBS method and to verify the possibility of using the evaluation of total coliforms in 1 mL of water as a sufficient parameter to roughly though accurately determine water microbiological quality. The MBS method was then tested “on field” to assess the microbiological quality of water sources in the city of Douala (Cameroon, Central Africa). Analyses were performed on both dug and drilled wells in different periods of the year. Results confirm that the MBS method appears to be a valid and accurate method to evaluate the microbiological quality of many water sources and it can be of valuable aid in developing countries. PMID:26308038

Field Application of the Micro Biological Survey Method for a Simple and Effective Assessment of the Microbiological Quality of Water Sources in Developing Countries.

PubMed

Arienzo, Alyexandra; Sobze, Martin Sanou; Wadoum, Raoul Emeric Guetiya; Losito, Francesca; Colizzi, Vittorio; Antonini, Giovanni

2015-08-25

According to the World Health Organization (WHO) guidelines, "safe drinking-water must not represent any significant risk to health over a lifetime of consumption, including different sensitivities that may occur between life stages". Traditional methods of water analysis are usually complex, time consuming and require an appropriately equipped laboratory, specialized personnel and expensive instrumentation. The aim of this work was to apply an alternative method, the Micro Biological Survey (MBS), to analyse for contaminants in drinking water. Preliminary experiments were carried out to demonstrate the linearity and accuracy of the MBS method and to verify the possibility of using the evaluation of total coliforms in 1 mL of water as a sufficient parameter to roughly though accurately determine water microbiological quality. The MBS method was then tested "on field" to assess the microbiological quality of water sources in the city of Douala (Cameroon, Central Africa). Analyses were performed on both dug and drilled wells in different periods of the year. Results confirm that the MBS method appears to be a valid and accurate method to evaluate the microbiological quality of many water sources and it can be of valuable aid in developing countries.

Evaluation of a GMP training of milkers in dairy goat farms in São Paulo, Brazil.

PubMed

Tavolaro, Paula; Oliveira, Carlos A F

2006-02-01

A good manufacturing practices (GMP) training course was applied for goat milkers and evaluated using microbiological analysis in milk before and after training. Milkers from three dairy goat farms located in São Paulo, Brazil, were submitted to a one-hour course on GMP and recommended guidelines for milking. Samples of raw milk were collected before and one to two months after training, and analysed for aerobic mesophilic, psychrotrophic, coliform, Staphylococcus aureus and Salmonella spp counts. Only mesophilic counts decreased (p < 0.05) after training in two of three farms studied. Although important to assess the overall quality of milk, microbiological parameters should not be used alone for the evaluation of GMP effectiveness for goat milkers.

Medical devices; immunology and microbiology devices; classification of nucleic acid-based devices for the detection of Mycobacterium tuberculosis complex and the genetic mutations associated with antibiotic resistance. Final order.

PubMed

2014-10-22

The Food and Drug Administration (FDA) is classifying nucleic acid-based in vitro diagnostic devices for the detection of Mycobacterium tuberculosis complex (MTB-complex) and the genetic mutations associated with MTB-complex antibiotic resistance in respiratory specimens devices into class II (special controls). The Agency is classifying the device into class II (special controls) because special controls, in addition to general controls, will provide a reasonable assurance of safety and effectiveness of the device.

One Small Step for the Gram Stain, One Giant Leap for Clinical Microbiology

PubMed Central

2016-01-01

The Gram stain is one of the most commonly performed tests in the clinical microbiology laboratory, yet it is poorly controlled and lacks standardization. It was once the best rapid test in microbiology, but it is no longer trusted by many clinicians. The publication by Samuel et al. (J. Clin. Microbiol. 54:1442–1447, 2016, http://dx.doi.org/10.1128/JCM.03066-15) is a start for those who want to evaluate and improve Gram stain performance. In an age of emerging rapid molecular results, is the Gram stain still relevant? How should clinical microbiologists respond to the call to reduce Gram stain error rates? PMID:27008876

PCR identification of bacteria in blood culture does not fit the daily workflow of a routine microbiology laboratory.

PubMed

Karumaa, Santra; Kärpänoja, Pauliina; Sarkkinen, Hannu

2012-03-01

We have evaluated the GenoType blood culture assay (Hain Lifescience, Nehren, Germany) for the identification of bacteria in 233 positive blood cultures and assessed its suitability in the workflow of a routine microbiology laboratory. In 68/233 (29.2%) samples, the culture result could not be confirmed by the GenoType assay due to a lack of primers in the test, multiple organisms in the sample, or inconsistency with respect to the identification by culture. Although the GenoType blood culture assay gives satisfactory results for bacteria for which primers are available, there are difficulties in applying the test in the routine microbiology laboratory.

The effect of inoculum source and fluid shear force on the development of in vitro oral multispecies biofilms.

PubMed

Fernández, C E; Aspiras, M B; Dodds, M W; González-Cabezas, C; Rickard, A H

2017-03-01

Saliva has been previously used as an inoculum for in vitro oral biofilm studies. However, the microbial community profile of saliva is markedly different from hard- and soft-tissue-associated oral biofilms. Here, we investigated the changes in the biofilm architecture and microbial diversity of in vitro oral biofilms developed from saliva, tongue or plaque-derived inocula under different salivary shear forces. Four inoculum types (saliva, bacteria harvested from the tongue, toothbrush and curette-harvested plaque) were collected and pooled. Biofilms (n ≥ 15) were grown for 20 h in cell-free human saliva flowing at three different shear forces. Stained biofilms were imaged using a confocal laser scanning microscope. Biomass, thickness and roughness were determined by image analysis and bacterial community composition analysed using Ion Torrent. All developed biofilms showed a significant reduction in observed diversity compared with their respective original inoculum. Shear force altered biofilm architecture of saliva and curette-collected plaque and community composition of saliva, tongue and curette-harvested plaque. Different intraoral inocula served as precursors of in vitro oral polymicrobial biofilms which can be influenced by shear. Inoculum selection and shear force are key factors to consider when developing multispecies biofilms within in vitro models. © 2016 The Society for Applied Microbiology.

Apical extrusion of Enterococcus faecalis using three different rotary instrumentation techniques: an in vitro study.

PubMed

Taneja, Sonali; Kumari, Manju; Barua, Madhumita; Dudeja, Chetna; Malik, Meeta

2015-01-01

To compare the apical extrusion of Enterococcus faecalis after instrumentation with three different Ni-Ti rotary instruments- An in vitro study. In vitro study Methods and Material: Forty freshly extracted mandibular premolars were mounted in bacteria collection apparatus and root canals were contaminated with a suspension of Enterococcus faecalis. The contaminated teeth were divided into 4 groups of 10 teeth each according to rotary system used for instrumentation: Group1: Hyflex files, Group 2: GTX files, Group 3: Protaper files and Group 4: control group (no instrumentation). Bacteria extruded after preparations were collected into vials and microbiological samples were incubated in BHI broth for 24 hrs. The colony forming units were determined for each sample. Statistical analysis was done using one way ANOVA followed by post hoc independent " t" test. GTX files extruded least amount of bacteria followed by Hyflex files. Maximum extrusion of E. faecalis was seen in rotary Protaper group. Least amount of extrusion was seen with GTX files followed by Hyflex files and then rotary Protaper system.

A comparison of efficiencies of microbiological pollution removal in six sewage treatment plants with different treatment systems.

PubMed

Kistemann, Thomas; Rind, Esther; Rechenburg, Andrea; Koch, Christoph; Classen, Thomas; Herbst, Susanne; Wienand, Ina; Exner, Martin

2008-10-01

Six sewage treatment plants (STP) were investigated over a 12-month period in order to measure the microbiological load of untreated municipal wastewater and to evaluate the removal efficiencies of different treatment systems. The STP investigated can be classified into three categories: bigger plants with tertiary treatment, smaller plants with enhanced secondary treatment, and very small compact facilities. The plants studied had a considerable quantitative impact on the hydrology of the catchment area; consequently, it was anticipated that the microbiological load of the effluent would also be significant. Eighty samples were taken from the influent and effluent of the STP, regardless of weather conditions, and several bacterial and two parasitological parameters were analysed. The average microbiological reduction of each STP was dependent on its capacity and treatment procedures and varied between 1.9 and 3.5log10. Small compact facilities had a significantly lower removal efficiency (2.0+/-1log10) and discharged treated wastewater with a poorer microbiological quality compared to larger plants with tertiary treatment or with enhanced secondary treatment (2.8log10). Final sand filtration and extensive intermediate settling considerably improved the overall microbiological removal efficiency. During the study period, the microbiological water quality of the receiving water course was not significantly impaired by the discharge of any of the investigated plants; however, the compact facilities showed critical treatment deficiencies. In particular, the reduction of Giardia cysts was insufficient (<1.5log10) compared to that of the bigger plants (>3.0log10). In order to quantify the overall impact of microbiological loads on the receiving watercourse in this catchment area, it is also necessary to assess the pollution from combined sewer overflow basins and diffuse pollution. This will be considered in subsequent studies.

Evaluation of fleroxacin (RO 23-6240) as single-oral-dose therapy of culture-proven chancroid in Nairobi, Kenya.

PubMed Central

MacDonald, K S; Cameron, D W; D'Costa, L; Ndinya-Achola, J O; Plummer, F A; Ronald, A R

1989-01-01

Chancroid is gaining importance as a sexually transmitted disease because of its association with transmission of human immunodeficiency virus type 1 (HIV-1). Effective, simply administered therapy for chancroid is necessary. Fleroxacin is effective against Haemophilus ducreyi in vitro. We performed an initial randomized clinical trial to assess the efficacy of fleroxacin for treatment of chancroid in Nairobi, Kenya. Fifty-three men with culture-positive chancroid were randomly assigned to receive either 200 mg (group 1) or 400 mg (group 2) of fleroxacin as a single oral dose. Groups 1 and 2 were similar with regard to severity of disease, bubo formation, and HIV-1 status. A satisfactory clinical response to therapy was noted in 23 of 26 patients (88%) in group 1 and 18 of 23 patients (78%) in group 2. Bacteriological failure occurred in 1 of 26 evaluable patients (4%) in group 1 and 4 of 23 evaluable patients (17%) in group 2. Two of 37 HIV-1-seronegative men (5%) and 3 of 11 HIV-1-infected men (27%) were bacteriological failures. Fleroxacin, 200 or 400 mg as a single oral dose, is efficacious therapy for microbiologically proven chancroid in patients who do not have concurrent HIV-1 infection. Among HIV-1-infected men, a single dose of 200 or 400 mg of fleroxacin is inadequate therapy for chancroid. PMID:2502065

Evaluation of methods for the microbiological control of natural corks for sparkling wine bottles.

PubMed

Centeno, S; Calvo, M A

2000-01-01

The various parameters proposed in Norm 0.20/95 of Catalunya (Spain) for the microbiological analysis of natural corks for sparkling wines were evaluated. The best results were obtained through the use of 1/4 Ringer's solution or saline for rinsing with an agitation time of 30 min, and an agitation speed of 150-200 rpm. Tryptone soya agar (TSA) and Sabouraud dextrose agar (SDA) were used as a culture medium for the bacteria and fungi, respectively, and a cultivation time of 48 h and incubation temperatures of 37 +/- 2 degrees C for bacteria and 28 degrees C for yeast and filamentous fungi.

Evaluation of the Biomic V3 Microbiology System for Identification of Selected Species on BBL CHROMagar Orientation Agar and CHROMagar MRSA Medium ▿

PubMed Central

Baron, Ellen Jo; D'Souza, Holly; Qi Wang, Andrew; Gibbs, David L.

2008-01-01

The Biomic V3 microbiology system identifies bacteria by reading the color of colonies selected by the user. For CHROMagar orientation, Biomic results agreed with conventional methods for 94% of the strains assayed. For CHROMagar MRSA, Biomic correctly identified 100% of the strains tested and did not misidentify two methicillin-susceptible Staphylococcus aureus strains growing on the plates. PMID:18701661

Antifungal and antimycotoxigenic potency of Solanum torvum Swartz. leaf extract: isolation and identification of compound active against mycotoxigenic strains of Aspergillus flavus and Fusarium verticillioides.

PubMed

Abhishek, R U; Thippeswamy, S; Manjunath, K; Mohana, D C

2015-12-01

The main objective of this study was to investigate the antifungal effect of Solanum torvum leaves against different field and storage fungi, and to identify its active compound. In addition, to evaluate in vitro and in vivo inhibitory efficacy on toxigenic strains of Aspergillus flavus and Fusarium verticillioides. Leaves of S. torvum were sequentially extracted with petroleum ether, toluene, chloroform, methanol and ethanol. The antifungal compound isolated from chloroform extract was identified as torvoside K based on spectral analysis. The antifungal activity of chloroform extract and torvoside K was determined by broth microdilution and poisoned food techniques. The minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC) and zone of inhibition (ZOI) were recorded. Further, inhibitory effects of chloroform extract and torvoside K on growth of A. flavus and F. verticillioides, and their toxin productions were evaluated using in vitro and in vivo assays. Torvoside K showed the significant activity against tested fungi with ZOIs and MICs ranging from 33·4 to 87·4% and 31·25-250 μg ml(-1) , respectively. Further, torvoside K showed concentration-dependent antimycotoxigenic activity against aflatoxin B1 and fumonisin B1 production by A. flavus and F. verticillioides, respectively. It was observed that the compound torvoside K significantly inhibited the growth of all fungi tested. Growth of A. flavus and F. verticillioides, and aflatoxin B1 and fumonisin B1 productions were completely inhibited in vitro and in vivo by torvoside K with increasing concentration. Control of mycotoxigenic fungi requires compounds that able to inhibit both fungal growth and mycotoxin production. The antimycotoxigenic potential of torvoside K of S. torvum is described in this study for the first time. The results indicate the possible use of S. torvum as source of antifungal agents against postharvest fungal infestation of food commodities and mycotoxin contaminations. © 2015 The Society for Applied Microbiology.

A biodegradable antibiotic-eluting PLGA nanofiber-loaded deproteinized bone for treatment of infected rabbit bone defects.

PubMed

Gao, Jianting; Huang, Guofeng; Liu, Guojun; Liu, Yan; Chen, Qi; Ren, Lei; Chen, Changqing; Ding, Zhenqi

2016-08-01

We fabricated a biodegradable antibiotic-eluting poly(d,l)-lactide-co-glycolide nanofiber-loaded deproteinized bone (ANDB) scaffold that provided sustained delivery of vancomycin to repair methicillin-resistant Staphylococcus aureus bone defects. To fabricate the biodegradable ANDB, poly(d,l)-lactide-co-glycolide and vancomycin were first dissolved in 1,1,1,3,3,3-hexafluoro-2-propano. The solution was then electrospun to produce biodegradable antibiotic-eluting membranes that were deposited on the surface of bovine deproteinized cancellous bone. We used scanning electron microscopy to determine the properties of the scaffold. Both elution and high-performance liquid chromatography assays were used to evaluate the in vitro vancomycin release rate from the ANDB scaffold. Three types of scaffolds were co-cultured with bacteria to confirm the in vitro antibacterial activity. The infected bone defect rabbit model was induced by injecting 10(7) colony forming units of a methicillin-resistant Staphylococcus aureus strain into the radial defect of rabbits. Animals were then separated into treatment groups and implanted according to the following scheme: ANDB scaffold in group A, poly(d,l)-lactide-co-glycolide nanofiber-loaded deproteinized bone (NDB) scaffold with intravenous (i.v.) vancomycin in group B, and NDB scaffold alone in group C. Treatment efficacy was evaluated after eight weeks using radiological, microbiological, and histological examinations. In vitro results revealed that biodegradable ANDB scaffolds released concentrations of vancomycin that were greater than the minimum inhibitory concentration for more than four weeks. Bacterial inhibition tests also confirmed antibacterial efficacy lasted for approximately four weeks. Radiological and histological scores obtained in vivo revealed significant differences between groups A, B and C. Importantly, group A had significantly lower bacterial load and better bone regeneration when compared to either group B or C. Collectively, these results show that our fabricated ANDB scaffolds possess: (1) effective bactericidal activity against methicillin-resistant Staphylococcus aureus, (2) the ability to promote site-specific bone regeneration, and (3) the potential for use in the treatment of infected bone defects. © The Author(s) 2016.

In vitro evaluation of antibiotic diffusion from antibiotic-impregnated biodegradable beads and polymethylmethacrylate beads.

PubMed Central

Mader, J T; Calhoun, J; Cobos, J

1997-01-01

Antibiotic-impregnated beads are used in the dead bone space following debridement surgery to deliver local, high concentrations of antibiotics. Polymethylmethacrylate (PMMA), 2,000-molecular-weight (MW) polylactic acid (PLA), Poly(DL-lactide)-coglycolide (PL:CG; 90:10, 80:20, and 70:30), and the combination 2,000-MW PLA-70:20 PL:CG were individually mixed with clindamycin, tobramycin, or vancomycin. Beads were placed in 1 ml of phosphate-buffered saline (PBS) and incubated at 37 degrees C. The PBS was changed daily, and the removed PBS samples were stored at -70 degrees C until the antibiotic in each sample was determined by microbiological disk diffusion assay. Nondissolving PMMA beads with tobramycin and clindamycin had concentrations well above breakpoint sensitivity concentrations (i.e., the antibiotic concentrations at the transition point between bacterial killing and resistance to the antibiotic) for more than 90 days, but vancomycin concentrations dropped by day 12. ALl PLA, PL:CG, and the 2,000-MW PLA-70:30 PL:CG biodegradable beads release high concentrations of all the antibiotics in vitro for the period of time needed to treat bone infections (i.e., 4 to 8 weeks). Antibiotic-loaded PLA and PL:CG beads have the advantage of better antibiotic elution and the ability to biodegradable (thereby averting the need for secondary surgery for bead removal) compared to the PMMA beads presently used in the clinical setting. PMID:9021200

Comparison of PrestoBlue® and plating method to evaluate antimicrobial activity of ascorbic acid, boric acid and curcumin in an in vitro gastrointestinal model.

PubMed

Hernandez-Patlan, D; Solis-Cruz, B; Méndez-Albores, A; Latorre, J D; Hernandez-Velasco, X; Tellez, G; López-Arellano, R

2018-02-01

To compare the conventional plating method vs a fluorometric method using PrestoBlue ® as a dye by determining the antimicrobial activity of two organic acids and curcumin (CUR) against Salmonella Enteritidis in an avian in vitro digestion model that simulates the crop, proventriculus and intestine. A concentration of 10 8  CFU per ml of S. Enteritidis was exposed to groups with different rates of ascorbic acid (AA), boric acid (BA) and CUR. Significant differences were observed when the means of the treatments were compared with the controls in the compartments that simulate the crop and intestine (P < 0·05). Ascorbic acid alone and high rates of AA in the mixtures were the most efficient treatments in the crop compartment. However, in the intestinal compartment BA alone and at different rates in the mixture BA-CUR (1 : 1) were the best treatments to decrease the concentration of S. Enteritidis. The results of this study suggest that there could be an antagonistic bactericidal effect between AA and CUR and AA and BA as well as a synergistic bactericidal effect between BA and CUR. These findings may contribute to the development of a formulation with microencapsulated compounds to liberate them in different compartments to combat S. Enteritidis infections in broiler chickens. © 2017 The Society for Applied Microbiology.

In vitro antimalarial activity of novel semisynthetic nocathiacin I antibiotics.

PubMed

Sharma, Indu; Sullivan, Margery; McCutchan, Thomas F

2015-01-01

Presently, the arsenal of antimalarial drugs is limited and needs to be replenished. We evaluated the potential antimalarial activity of two water-soluble derivatives of nocathiacin (BMS461996 and BMS411886) against the asexual blood stages of Plasmodium falciparum. Nocathiacins are a thiazolyl peptide group of antibiotics, are structurally related to thiostrepton, have potent activity against a wide spectrum of multidrug-resistant Gram-positive bacteria, and inhibit protein synthesis. The in vitro growth inhibition assay was done using three laboratory strains of P. falciparum displaying various levels of chloroquine (CQ) susceptibility. Our results indicate that BMS461996 has potent antimalarial activity and inhibits parasite growth with mean 50% inhibitory concentrations (IC50s) of 51.55 nM for P. falciparum 3D7 (CQ susceptible), 85.67 nM for P. falciparum Dd2 (accelerated resistance to multiple drugs [ARMD]), and 99.44 nM for P. falciparum K1 (resistant to CQ, pyrimethamine, and sulfadoxine). Similar results at approximately 7-fold higher IC50s were obtained with BMS411886 than with BMS461996. We also tested the effect of BMS491996 on gametocytes; our results show that at a 20-fold excess of the mean IC50, gametocytes were deformed with a pyknotic nucleus and growth of stage I to IV gametocytes was arrested. This preliminary study shows a significant potential for nocathiacin analogues to be developed as antimalarial drug candidates and to warrant further investigation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Compatibility of chemical insecticides and entomopathogenic fungi for control of soybean defoliating pest, Rachiplusia nu.

PubMed

Pelizza, Sebastian A; Schalamuk, Santiago; Simón, María R; Stenglein, Sebastian A; Pacheco-Marino, Suani G; Scorsetti, Ana C

Rachiplusia nu (Guenée) (Lepidoptera: Noctuidae) is one of the major lepidopteran pests defoliating soybeans (Glycine max Merrill) in Argentina. The combined use of chemical insecticides and entomopathogenic fungi is a promising pest-control option to minimize adverse chemical effects. In this work, we evaluated the interactions between five insecticides-two being considered biorational-and five fungal entomopathogenic strains under laboratory conditions in order to determine the possible usefulness of combinations of these agents against R. nu. The insecticides were tested for compatibility at four doses by in vitro bioassay and for the lethality of R. nu by inoculations at three doses. Fungal strains were applied at 1×10 8 , 1×10 6 , and 1×10 4 conidia/ml. The combinations of those insecticides with Beauveria bassiana (LPSc 1067, LPSc 1082, LPSc 1098), Metarhizium anisopliae (LPSc 907), and Metarhizium robertsii (LPSc 963) caused higher R. nu-larval mortalities than any of the individual agents alone. We observed significant differences in the in vitro conidial viability, vegetative growth, and conidia production of the five strains of entomopathogenic fungi exposed to different doses of the chemical insecticides. The combination gamma-cyhalothrin-LPSc-1067 caused the highest percent mortality of R. nu larvae, with synergism occurring between the two agents at 50% and 25% of the maximum field doses. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Endophytic colonization and biocontrol performance of Pseudomonas fluorescens PICF7 in olive (Olea europaea L.) are determined neither by pyoverdine production nor swimming motility.

PubMed

Maldonado-González, M Mercedes; Schilirò, Elisabetta; Prieto, Pilar; Mercado-Blanco, Jesús

2015-09-01

Pseudomonas fluorescens PICF7 is an indigenous inhabitant of olive (Olea europaea L.) rhizosphere, able to display endophytic lifestyle in roots, to induce a wide range of defence responses upon colonization of this organ and to exert effective biological control against Verticillium wilt of olive (VWO) (Verticillium dahliae). We aimed to evaluate the involvement of specific PICF7 phenotypes in olive root colonization and VWO biocontrol effectiveness by generating mutants impaired in swimming motility (fliI) or siderophore pyoverdine production (pvdI). Besides, the performance of mutants with diminished in vitro growth in potato dextrose agar medium (gltA) and cysteine (Cys) auxotrophy was also assessed. Results showed that olive root colonization and VWO biocontrol ability of the fliI, pvdI and gltA mutants did not significantly differ from that displayed by the parental strain PICF7. Consequently, altered in vitro growth, swimming motility and pyoverdine production contribute neither to PICF7 VWO suppressive effect nor to its colonization ability. In contrast, the Cys auxotroph mutant showed reduced olive root colonization capacity and lost full biocontrol efficacy. Moreover, confocal laser scanning microscopy revealed that all mutants tested were able to endophytically colonize root tissue to the same extent as wild-type PICF7, discarding these traits as relevant for its endophytic lifestyle. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

Evaluation of in vitro serial antibiotic elution from meropenem-impregnated polymethylmethacrylate beads after ethylene oxide gas and autoclave sterilization.

PubMed

Báez, L A; Langston, C; Givaruangsawat, S; McLaughlin, R

2011-01-01

To determine the elution properties of meropenem and to compare the elutions of meropenem-impregnated polymethylmethacrylate (PMMA) beads without sterilization (P-M-C) to those sterilized with steam (P-M-A) and ethylene oxide gas (P-M-EO). A commercial bead mould was used to produce four groups of beads: one group without antibiotic (negative control), and three groups of meropenem-impregnated beads: P-M-C, P-M-A, and P-M-EO. The beads were placed in a phosphate buffered solution and eluent samples were collected. Concentrations of the antibiotic in eluent samples from the two sterilized groups and the control beads were determined using a microbiological assay at 1, 3, 6 and 12 hours and at 1, 2, 3, 6, 9, 12, 15, 18, 22, 26, and 30 days. The microbiological assay resulted in no zone of inhibition at all time periods for the P-M-A samples and the samples of PMMA without antimicrobial. The meropenem concentration on the eluent remained above 4 mcg/ml for 15 days in the P-M-C group and until day 18 for P-M-EO group. There was no statistical difference in AUC0-∞ (p<0.318), however significance did occur for MRT (p<0.005) when comparing P-M-C and P-M-EO with the later being higher. The meropenem incorporated in the PMMA beads eluted effectively and gradually decreased after the 24 hour peak, but remained above the concentration level of 4 mcg/ml for 15 days in the P-M-C group and until day 18 for P-M-EO group. Ethylene oxide does not adversely affect meropenem's elution from PMMA beads.

A Resorbable Antibiotic-Eluting Polymer Composite Bone Void Filler for Perioperative Infection Prevention in a Rabbit Radial Defect Model

PubMed Central

Brooks, Benjamin D.; Sinclair, Kristofer D.; Grainger, David W.; Brooks, Amanda E.

2015-01-01

Nearly 1.3 million total joint replacement procedures are performed in the United States annually, with numbers projected to rise exponentially in the coming decades. Although finite infection rates for these procedures remain consistently low, device-related infections represent a significant cause of implant failure, requiring secondary or revision procedures. Revision procedures manifest several-fold higher infection recurrence rates. Importantly, many revision surgeries, infected or not, require bone void fillers to support the host bone and provide a sufficient tissue bed for new hardware placement. Antibiotic-eluting bone void fillers (ABVF), providing both osteoconductive and antimicrobial properties, represent one approach for reducing rates of orthopedic device-related infections. Using a solvent-free, molten-cast process, a polymer-controlled antibiotic-eluting calcium carbonate hydroxyapatite (HAP) ceramic composite BVF (ABVF) was fabricated, characterized, and evaluated in vivo using a bacterial challenge in a rabbit radial defect window model. ABVF loaded with tobramycin eliminated the infectious burden in rabbits challenged with a clinically relevant strain of Staphylococcus aureus (inoculum as high as 107 CFU). Histological, microbiological, and radiographic methods were used to detail the effects of ABVF on microbial challenge to host bone after 8 weeks in vivo. In contrast to the HAP/BVF controls, which provided no antibiotic protection and required euthanasia 3 weeks post-operatively, tobramycin-releasing ABVF animals showed no signs of infection (clinical, microbiological, or radiographic) when euthanized at the 8-week study endpoint. ABVF sites did exhibit fibrous encapsulation around the implant at 8 weeks. Local antibiotic release from ABVF to orthopedic sites requiring bone void fillers eliminated the periprosthetic bacterial challenge in this 8-week in vivo study, confirming previous in vitro results. PMID:25815727

Relevance of various animal models of human infections to establish therapeutic equivalence of a generic product of piperacillin/tazobactam.

PubMed

Agudelo, Maria; Rodriguez, Carlos A; Zuluaga, Andres F; Vesga, Omar

2015-02-01

After demonstrating with diverse intravenous antibacterials that pharmaceutical equivalence (PE) does not predict therapeutic equivalence, we tested a single generic product of piperacillin/tazobactam (TZP) in terms of PE, pharmacokinetics and in vitro/vivo pharmacodynamics against several pathogens in neutropenic mouse thigh, lung and brain infection models. A generic product was compared head-to-head against the innovator. PE was evaluated by microbiological assay. Single-dose serum pharmacokinetics were determined in infected mice, and the MIC/MBC were determined by broth microdilution. In vivo experiments were done in a blind fashion. Reproducibility was tested on different days using different infecting organisms and animal models. Neutropenic MPF mice were infected in the thighs with Staphylococcus aureus GRP-0057 or Pseudomonas aeruginosa PA01 and in the lungs or brain with Klebsiella pneumoniae ATCC 10031. Treatment started 2h (thigh and brain) or 14 h (lung) after infection and was administered every 3h over 24h (thigh and lung) or 48 h (brain). Both products exhibited the same MIC/MBC against each strain, yielded overlaid curves in the microbiological assay (P>0.21) and were bioequivalent (IC90 83-117% for AUC test/reference ratio). In vivo, the generic product and innovator were again undistinguishable in all models and against the different bacterial pathogens involved. The relevance of these neutropenic murine models of infection was established by demonstrating their accuracy to predict the biological response following simultaneous treatment with a generic product or the innovator of TZP. Therapeutic equivalence of the generic product was proved in every model and against different pathogens. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Relation between microbiological quality, metabolite production and sensory quality of equilibrium modified atmosphere packaged fresh-cut produce.

PubMed

Jacxsens, L; Devlieghere, F; Ragaert, P; Vanneste, E; Debevere, J

2003-06-25

The quality of four types of fresh-cut produce, packaged in consumer-sized packages under an equilibrium modified atmosphere and stored at 7 degrees C, was assessed by establishing the relation between the microbial outgrowth and the corresponding production of nonvolatile compounds and related sensory disorders. In vitro experiments, performed on a lettuce-juice-agar, demonstrated the production of nonvolatile compounds by spoilage causing lactic acid bacteria and Enterobacteriaceae. Pseudomonas fluorescens and yeasts, however, were not able to produce detectable amounts of nonvolatile metabolites. The type of spoilage and quality deterioration in vivo depended on the type of vegetable. Mixed lettuce and chicory endives, leafy tissues, containing naturally low concentrations of sugars, showed a spoilage dominated by Gram-negative microorganisms, which are not producing nonvolatile compounds. Sensory problems were associated with visual properties and the metabolic activity of the plant tissue. Mixed bell peppers and grated celeriac, on the other hand, demonstrated a fast and intense growth of spoilage microorganisms, dominated by lactic acid bacteria and yeasts. This proliferation resulted in detectable levels of organic acids and the rejection by the trained sensory panel was based on the negative perception of the organoleptical properties (off-flavour, odour and taste). The applied microbiological criteria corresponded well with detectable changes in sensory properties and measurable concentrations of nonvolatile compounds, surely in the cases where lactic acid bacteria and yeasts were provoking spoilage. Consequently, the freshness of minimally processed vegetables, sensitive for outgrowth of lactic acid bacteria and yeasts (e.g., carrots, celeriac, bell peppers, mixtures with non-leafy vegetables) can be evaluated via analysis of the produced nonvolatile compounds.

Effect of Inulin on the Viability of L. plantarum during Storage and In Vitro Digestion and on Composition Parameters of Vegetable Fermented Juices.

PubMed

Valero-Cases, Estefanía; Frutos, María José

2017-06-01

The prebiotic effect of different concentrations of inulin (0, 1 and 2%) on the growth and survival of Lactobacillus plantarum (LP) CECT 220 in blended carrot and orange juices was investigated after 24 h of fermentation, during 30 days of storage at 4 °C and through the phases of gastrointestinal digestion after different storage periods. Microbiological and chemical determinations were also carried out in all juices. The lactic fermentation increased the shelf life of the fermented juices with inulin. The hygienic-sanitary quality in fermented juices was better than the control juices. During storage, the inulin improved the viability of LP and the monosaccharide concentration remained higher with respect to the juice without inulin (40% lower). At 30 days, the fermented juices with 2% inulin after in vitro digestion presented the highest survival of L. plantarum.

Fine needle aspiration cytology of granulomatous mastitis with special emphasis on microbiologic correlation.

PubMed

Nemenqani, Dalal; Yaqoob, Nausheen; Hafiz, Momein

2009-01-01

To describe the cytomorphology of granulomatous mastitis (GM) and to evaluate the causative agents involved, proven on the basis of microbiologic culture results and polymerase chain reaction (PCR) studies. We retrospectively reviewed the inflammatory breast aspirates reported at King Abdul Aziz Specialist Hospital and Al Hada Armed Forces Hospital, Taif, Kingdom of Saudi Arabia, from January 2000 until March 2008. The pathology reports, clinical information, slides, microbiologic culture results and tuberculosis (TB)/PCR were reviewed. Cases of inflammatory carcinoma or duct ectasia were excluded. A total of 49 cases of inflammatory breast aspirates were identified, of which 15 cases were GM. The microbiologic cultures of all 15 cases were available. Six of 15 cases had positive culture for Brucella melitenses, and 2 cases were positive for TB, which was further confirmed by TB/PCR. The fungal cultures were negative in all the cases. Seven of 15 cases were classified as idiopathic GM. Fine needle aspiration cytology was found to be a useful tool in the early diagnosis of GM and its classification if performed by a pathologist as the material can be submitted for culture. The definitive diagnosis can be established by a combination of the cytomorphologic features and microbiologic studies.

Microbiological performance of a food safety management system in a food service operation.

PubMed

Lahou, E; Jacxsens, L; Daelman, J; Van Landeghem, F; Uyttendaele, M

2012-04-01

The microbiological performance of a food safety management system in a food service operation was measured using a microbiological assessment scheme as a vertical sampling plan throughout the production process, from raw materials to final product. The assessment scheme can give insight into the microbiological contamination and the variability of a production process and pinpoint bottlenecks in the food safety management system. Three production processes were evaluated: a high-risk sandwich production process (involving raw meat preparation), a medium-risk hot meal production process (starting from undercooked raw materials), and a low-risk hot meal production process (reheating in a bag). Microbial quality parameters, hygiene indicators, and relevant pathogens (Listeria monocytogenes, Salmonella, Bacillus cereus, and Escherichia coli O157) were in accordance with legal criteria and/or microbiological guidelines, suggesting that the food safety management system was effective. High levels of total aerobic bacteria (>3.9 log CFU/50 cm(2)) were noted occasionally on gloves of food handlers and on food contact surfaces, especially in high contamination areas (e.g., during handling of raw material, preparation room). Core control activities such as hand hygiene of personnel and cleaning and disinfection (especially in highly contaminated areas) were considered points of attention. The present sampling plan was used to produce an overall microbiological profile (snapshot) to validate the food safety management system in place.

Does implant coating with antibacterial-loaded hydrogel reduce bacterial colonization and biofilm formation in vitro?

PubMed

Drago, Lorenzo; Boot, Willemijn; Dimas, Kostantinos; Malizos, Kostantinos; Hänsch, Gertrud M; Stuyck, Jos; Gawlitta, Debby; Romanò, Carlo L

2014-11-01

Implant-related infections represent one of the most severe complications in orthopaedics. A fast-resorbable, antibacterial-loaded hydrogel may reduce or prevent bacterial colonization and biofilm formation of implanted biomaterials. We asked: (1) Is a fast-resorbable hydrogel able to deliver antibacterial compounds in vitro? (2) Can a hydrogel (alone or antibacterial-loaded) coating on implants reduce bacterial colonization? And (3) is intraoperative coating feasible and resistant to press-fit implant insertion? We tested the ability of Disposable Antibacterial Coating (DAC) hydrogel (Novagenit Srl, Mezzolombardo, Italy) to deliver antibacterial agents using spectrophotometry and a microbiologic assay. Antibacterial and antibiofilm activity were determined by broth microdilution and a crystal violet assay, respectively. Coating resistance to press-fit insertion was tested in rabbit tibias and human femurs. Complete release of all tested antibacterial compounds was observed in less than 96 hours. Bactericidal and antibiofilm effect of DAC hydrogel in combination with various antibacterials was shown in vitro. Approximately 80% of the hydrogel coating was retrieved on the implant after press-fit insertion. Implant coating with an antibacterial-loaded hydrogel reduces bacterial colonization and biofilm formation in vitro. A fast-resorbable, antibacterial-loaded hydrogel coating may help prevent implant-related infections in orthopaedics. However, further validation in animal models and properly controlled human studies is required.

Parasite-Mediated Degradation of Synthetic Ozonide Antimalarials Impacts In Vitro Antimalarial Activity.

PubMed

Giannangelo, Carlo; Stingelin, Lukas; Yang, Tuo; Tilley, Leann; Charman, Susan A; Creek, Darren J

2018-03-01

The peroxide bond of the artemisinins inspired the development of a class of fully synthetic 1,2,4-trioxolane-based antimalarials, collectively known as the ozonides. Similar to the artemisinins, heme-mediated degradation of the ozonides generates highly reactive radical species that are thought to mediate parasite killing by damaging critical parasite biomolecules. We examined the relationship between parasite dependent degradation and antimalarial activity for two ozonides, OZ277 (arterolane) and OZ439 (artefenomel), using a combination of in vitro drug stability and pulsed-exposure activity assays. Our results showed that drug degradation is parasite stage dependent and positively correlates with parasite load. Increasing trophozoite-stage parasitemia leads to substantially higher rates of degradation for both OZ277 and OZ439, and this is associated with a reduction in in vitro antimalarial activity. Under conditions of very high parasitemia (∼90%), OZ277 and OZ439 were rapidly degraded and completely devoid of activity in trophozoite-stage parasite cultures exposed to a 3-h drug pulse. This study highlights the impact of increasing parasite load on ozonide stability and in vitro antimalarial activity and should be considered when investigating the antimalarial mode of action of the ozonide antimalarials under conditions of high parasitemia. Copyright © 2018 American Society for Microbiology.

Clinical and pharmacokinetic drug evaluation of delafloxacin for the treatment of acute bacterial skin and skin structure infections.

PubMed

Bassetti, Matteo; Pecori, Davide; Cojutti, Piergiorgio; Righi, Elda; Pea, Federico

2017-11-01

In the era of multi-drug resistant pathogens, the adequate treatment of skin and skin structure infections remains a challenge for clinicians. Delafloxacin, with its broad spectrum against Gram-positive, Gram-negative and anaerobic organisms, represents a new therapeutic option in this setting, especially when coverage of methicillin-resistant Staphylococcus aureus is required in the empirical or targeted approach. Areas covered: In this drug evaluation, the Authors have reviewed the pharmacokinetic and pharmacodynamic characteristics of delafloxacin. In addition, recent data on clinical efficacy and safety from clinical trials have been included. Expert opinion: Delafloxacin represents an attractive therapeutic option due to a broad antimicrobial and favorable pharmacokinetic and pharmacodynamic profile. Several in vitro studies have demonstrated the low potential for resistance selection if used in empirical regimens. Delafloxacin is a promising candidate for the treatment of Gram-positive infections, especially if co-infection with other pathogens is suspected. This is because of the very low MIC of the agent for Gram-positive (including MRSA) and anaerobic bacteria and because of the wide spectrum of activity against Gram-negative organisms. For these interesting microbiological and PK/PD characteristics we expect future uses of this drug in other indications such as diabetic foot infection, osteomyelitis, prosthetic joint infections, abdominal infections and central nervous system infections.

Immunomodulating activity of exopolysaccharide-producing Leuconostoc mesenteroides strain NTM048 from green peas.

PubMed

Matsuzaki, C; Kamishima, K; Matsumoto, K; Koga, H; Katayama, T; Yamamoto, K; Hisa, K

2014-04-01

The present work was aimed to find novel probiotics to enhance the mucosal barrier function of humans. The effectiveness was evaluated in vitro and in vivo. Stimulation of IgA production in mucosal surfaces is one of the most beneficial traits of lactic acid bacteria (LAB) for enhancing the barrier. Therefore, 173 LAB strains were evaluated for the ability to induce IgA production using murine Peyer's patch cells. Strain NTM048 isolated from green peas showed the highest activity and was identified as Leuconostoc mesenteroides subsp. mesenteroides. This strain was found to tolerate gastrointestinal digestion and produce large amounts of exopolysaccharides, which possess IgA-inducing activity. Dietary supplementation with NTM048 induced a significant increase in the faecal IgA content and plasma IgA levels of BALB/cA mice. A gene expression analysis of Peyer's patch cells revealed that the transforming growth factor-β and activation-induced cytidine deaminase genes were upregulated by NTM048 intake. Strain NTM048 stimulates Peyer's patch cells to induce intestinal and systemic immune response, revealing the potential of NTM048 as a probiotic for enhancing the mucosal barrier function. This report demonstrates a food-applicable Leuconostoc mesenteroides strain secreting exopolysaccharide that shows high IgA-inducing ability. © 2013 The Society for Applied Microbiology.

Antimicrobial and plant growth-promoting properties of the cacao endophyte Bacillus subtilis ALB629.

PubMed

Falcäo, L L; Silva-Werneck, J O; Vilarinho, B R; da Silva, J P; Pomella, A W V; Marcellino, L H

2014-06-01

To investigate the effects of the endophyte Bacillus subtilisALB629 on the growth of cacao seedlings at early developmental stage and to evaluate its antimicrobial properties. Germinating cacao seeds were inoculated with ALB629, and seedlings growth was evaluated 30 days later. Significant increase (P < 0·05) was observed in the root system (up to 30%), leaf area (14%) and stem height (7·6%). ALB629 colonized the entire plant, prevailing over indigenous micro-organisms. In addition, it was tested in vitro, by pairing assays, and showed antagonistic effect against the phytopathogenic fungi Moniliophthora perniciosa, Colletotrichum sp. and C. gossypii. When tested in cacao-grafting procedure in the field, ALB629 increased the grafting success rate (24%), indicating its protective effect. In addition, this Bacillus secretes an antagonist compound, as shown by the antifungal activity of the cell-free culture. Bacillus subtilisALB629 promotes cacao root growth, besides promoting growth of the aerial part of cacao seedlings. It has antimicrobial properties and produces an antifungal compound. ALB629 presented beneficial characteristics for cacao cultivation, being a good biological control agent candidate. Furthermore, it is a potential source of antifungal compound with potential for commercial exploitation. © 2014 The Society for Applied Microbiology.

Dissecting the Structure-Function Relationship of a Fungicidal Peptide Derived from the Constant Region of Human Immunoglobulins.

PubMed

Ciociola, Tecla; Pertinhez, Thelma A; Giovati, Laura; Sperindè, Martina; Magliani, Walter; Ferrari, Elena; Gatti, Rita; D'Adda, Tiziana; Spisni, Alberto; Conti, Stefania; Polonelli, Luciano

2016-04-01

Synthetic peptides encompassing sequences related to the complementarity-determining regions of antibodies or derived from their constant region (Fc peptides) were proven to exert differential antimicrobial, antiviral, antitumor, and/or immunomodulatory activitiesin vitroand/orin vivo, regardless of the specificity and isotype of the parental antibody. Alanine substitution derivatives of these peptides exhibited unaltered, increased, or decreased candidacidal activitiesin vitro The bioactive IgG-derived Fc N10K peptide (NQVSLTCLVK) spontaneously self-assembles, a feature previously recognized as relevant for the therapeutic activity of another antibody-derived peptide. We evaluated the contribution of each residue to the peptide self-assembling capability by circular-dichroism spectroscopy. The interaction of the N10K peptide and its derivatives withCandida albicanscells was studied by confocal, transmission, and scanning electron microscopy. The apoptosis and autophagy induction profiles in yeast cells treated with the peptides were evaluated by flow cytometry, and the therapeutic efficacy against candidal infection was studied in aGalleria mellonellamodel. Overall, the results indicate a critical role for some residues in the self-assembly process and a correlation of that capability with the candidacidal activities of the peptidesin vitroand their therapeutic effectsin vivo. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

[Effectiveness of Beauveria bassiana (Baubassil®) on the common cattle tick Rhipicephalus microplus in the Department of Guajira, Colombia].

PubMed

Tofiño Rivera, Adriana P; Ortega Cuadros, Mailen; Pedraza Claros, Bertilda; Perdomo Ayola, Sandra C; Moya Romero, Diana Carolina

2018-02-02

The effectiveness of Baubassil ® (Beauveria bassiana) on the tick Rhipicephalus (Boophilus) microplus was evaluated. In the in vitro phase, the optimal germination temperature of the fungus was determined by microcultures at 25, 30 and 35°C and the mortality of ticks. In the field, in a randomized design, 30 cebuine cows; 15 cows were treated with Baubassil ® once a week at a 1×10 6 conidia/ml, and a control group was left untreated. It was observed that at temperatures of 25, 30 and 35°C, germination of the entomopathogen was 97.5, 94.7 and 6.3%, respectively. In animals treated with Baubassil ® obtained a corrected effectiveness of 96.8% on ticks in the fifth week of application. The use of Baubassil ® would be a valid alternative for controlling the cattle tick under the agroecological conditions of the Dry Caribbean. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Lymphoproliferative and gamma interferon responses to stress-regulated Mycobacterium avium subsp. paratuberculosis recombinant proteins.

PubMed

Gurung, Ratna B; Begg, Douglas J; Purdie, Auriol C; de Silva, Kumudika; Bannantine, John P; Whittington, Richard J

2014-06-01

Johne's disease in ruminants is a chronic infection of the intestines caused by Mycobacterium avium subsp. paratuberculosis. An important strategy to control disease is early detection, and a potentially efficient method for early detection is measurement of cell-mediated immune responses developed by the host in response to exposure or infection. One method is to measure lymphoproliferation and cytokine release from the host cells when exposed to the organism or parts of the organism. In this study, 10 recombinant M. avium subsp. paratuberculosis proteins known to be upregulated under in vitro stress conditions were evaluated by examining their ability to evoke memory as a result of exposure by vaccination or oral challenge with live Mycobacterium avium subsp. paratuberculosis. Out of 10 proteins, MAP2698c was found to induce higher cell-mediated immune responses in vaccinated and challenged sheep in comparison to healthy controls. The findings suggest that not all stress-regulated proteins have the diagnostic potential to detect cell-mediated immune responses in ovine paratuberculosis. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Laboratory Diagnosis of Sepsis? No SIRS, Not Just Yet.

PubMed

Dunne, W Michael

2015-08-01

In order to maximize the benefit of prompt antimicrobial therapy and avoid the risk associated with inappropriate use of antimicrobial agents, patients with suspected sepsis must be rapidly differentiated from patients with systemic inflammatory response syndrome (SIRS). In combination with standard microbiological testing, a number of biomarkers have been recently evaluated for this purpose, and the performance characteristics of the most promising of these are reviewed. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

[Demographic and clinical features of diagnosed individuals of enterobiasis in the southern Gran Canaria: sampling assessment].

PubMed

Carrillo-Quintero, D; Del Otero Sanz, L; Hernández-Egido, S; Martín Sánchez, A M

2016-12-01

Enterobius vermicularis, also known as pinworn, is the responsible agent for Human Enterobiasis. It is one of the most prevalent, but underrated, parasitic disease in children population. Diagnosis involves demonstration of either eggs or adult worms by Graham test. The aim of this study is to describe the clinical, demographic and microbiological features of patients with suspected diagnosis of Enterobiasis in southern Gran Canaria. Descriptive and prospective study of perianal samples evaluated by Graham test in the Microbiology Department of `Insular de Gran Canaria´ University Hospital between November 2014 and November 2015. Descriptive analysis to evaluate the correlation between clinical and demographic variables and the results of Graham test microbiological observation. 1,128 samples were analyzed. E. vermicularis was found in 11.4% of the samples. Among the positives samples, 88.4% belonged to children under 14 years, and 53.5% were male. Abdominal pain (18.6%), anal itching (11.6%), eosinophilia (8.5%) and intestinal parasitosis suspicion (7.8%) were the reasons of parasitological investigation request in positive samples. Nevertheless, a high proportion of the requests was not founded in a suspicious diagnosis or was unrelated to Enterobiasis. Enterobiasis is a common disease in primary health care and is of great importance in Gran Canaria. Quality in sample collection as well as diagnosis suspicious information are necessary for a good microbiological analysis.

Diagnosis of vulvovaginitis: comparison of clinical and microbiological diagnosis.

PubMed

Esim Buyukbayrak, Esra; Kars, Bulent; Karsidag, Ayse Yasemin Karageyim; Karadeniz, Bernan Ilkay; Kaymaz, Ozge; Gencer, Serap; Pirimoglu, Zehra Meltem; Unal, Orhan; Turan, Mehmet Cem

2010-11-01

The purpose of the present study was to compare the current diagnostic clinical and laboratory approaches to women with vulvovaginal discharge complaint. The secondary outcomes were to determine the prevalence of infections in our setting and to look for the relation between vulvovaginal infections and predisposing factors if present. Premenopausal women applying to our gynecology outpatient clinic with vaginal discharge complaint were enrolled prospectively into the study. Each patient evaluated clinically with direct observation of vaginal secretions, wet mount examination, whiff test, vaginal pH testing and chlamydia rapid antigen test. Each patient also evaluated microbiologically with vaginal discharge culture and gram staining. Clinical diagnosis was compared with the microbiological diagnosis (the gold standard). Diagnostic accuracy was measured with sensitivity, specificity, positive (ppv) and negative predictive values (npv). 460 patients were included in the study. 89.8% of patients received a clinical diagnosis whereas only 36% of them had microbiological diagnosis. The sensitivity, specificity, ppv, npv of clinical diagnosis over microbiological culture results were 95, 13, 38, 82%, respectively. The most commonly encountered microorganisms by culture were Candida species (17.4%) and Gardnerella vaginalis (10.2%). Clinically, the most commonly made diagnoses were mixed infection (34.1%), bacterial vaginosis (32.4%) and fungal infection (14.1%). Symptoms did not predict laboratory results. Predisposing factors (DM, vaginal douching practice, presence of IUD and usage of oral contraceptive pills) were not found to be statistically important influencing factors for vaginal infections. Clinical diagnosis based on combining symptoms with office-based testing improves diagnostic accuracy but is insufficient. The most effective approach also incorporates laboratory testing as an adjunct when a diagnosis is in question or treatment is failing.

Agreement between gastrointestinal panel testing and standard microbiology methods for detecting pathogens in suspected infectious gastroenteritis: Test evaluation and meta-analysis in the absence of a reference standard.

PubMed

Freeman, Karoline; Tsertsvadze, Alexander; Taylor-Phillips, Sian; McCarthy, Noel; Mistry, Hema; Manuel, Rohini; Mason, James

2017-01-01

Multiplex gastrointestinal pathogen panel (GPP) tests simultaneously identify bacterial, viral and parasitic pathogens from the stool samples of patients with suspected infectious gastroenteritis presenting in hospital or the community. We undertook a systematic review to compare the accuracy of GPP tests with standard microbiology techniques. Searches in Medline, Embase, Web of Science and the Cochrane library were undertaken from inception to January 2016. Eligible studies compared GPP tests with standard microbiology techniques in patients with suspected gastroenteritis. Quality assessment of included studies used tailored QUADAS-2. In the absence of a reference standard we analysed test performance taking GPP tests and standard microbiology techniques in turn as the benchmark test, using random effects meta-analysis of proportions. No study provided an adequate reference standard with which to compare the test accuracy of GPP and conventional tests. Ten studies informed a meta-analysis of positive and negative agreement. Positive agreement across all pathogens was 0.93 (95% CI 0.90 to 0.96) when conventional methods were the benchmark and 0.68 (95% CI: 0.58 to 0.77) when GPP provided the benchmark. Negative agreement was high in both instances due to the high proportion of negative cases. GPP testing produced a greater number of pathogen-positive findings than conventional testing. It is unclear whether these additional 'positives' are clinically important. GPP testing has the potential to simplify testing and accelerate reporting when compared to conventional microbiology methods. However the impact of GPP testing upon the management, treatment and outcome of patients is poorly understood and further studies are needed to evaluate the health economic impact of GPP testing compared with standard methods. The review protocol is registered with PROSPERO as CRD42016033320.

In Vitro Antiviral Activity and Resistance Profile Characterization of the Hepatitis C Virus NS5A Inhibitor Ledipasvir.

PubMed

Cheng, Guofeng; Tian, Yang; Doehle, Brian; Peng, Betty; Corsa, Amoreena; Lee, Yu-Jen; Gong, Ruoyu; Yu, Mei; Han, Bin; Xu, Simin; Dvory-Sobol, Hadas; Perron, Michel; Xu, Yili; Mo, Hongmei; Pagratis, Nikos; Link, John O; Delaney, William

2016-01-11

Ledipasvir (LDV; GS-5885), a component of Harvoni (a fixed-dose combination of LDV with sofosbuvir [SOF]), is approved to treat chronic hepatitis C virus (HCV) infection. Here, we report key preclinical antiviral properties of LDV, including in vitro potency, in vitro resistance profile, and activity in combination with other anti-HCV agents. LDV has picomolar antiviral activity against genotype 1a and genotype 1b replicons with 50% effective concentration (EC50) values of 0.031 nM and 0.004 nM, respectively. LDV is also active against HCV genotypes 4a, 4d, 5a, and 6a with EC50 values of 0.11 to 1.1 nM. LDV has relatively less in vitro antiviral activity against genotypes 2a, 2b, 3a, and 6e, with EC50 values of 16 to 530 nM. In vitro resistance selection with LDV identified the single Y93H and Q30E resistance-associated variants (RAVs) in the NS5A gene; these RAVs were also observed in patients after a 3-day monotherapy treatment. In vitro antiviral combination studies indicate that LDV has additive to moderately synergistic antiviral activity when combined with other classes of HCV direct-acting antiviral (DAA) agents, including NS3/4A protease inhibitors and the nucleotide NS5B polymerase inhibitor SOF. Furthermore, LDV is active against known NS3 protease and NS5B polymerase inhibitor RAVs with EC50 values equivalent to those for the wild type. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Effect of animal sera on Bacillus anthracis Sterne spore germination and vegetative cell growth.

PubMed

Bensman, M D; Mackie, R S; Minter, Z A; Gutting, B W

2012-08-01

 The aims of this work were to investigate the effects of sera on B. anthracis Sterne germination and growth. Sera examined included human, monkey and rabbit sera, as well as sera from eight other species.  Standard dilution plate assay (with and without heat kill) was used as a measure of germination, and spectroscopy was used to measure growth. In addition, a Coulter Counter particle counter was used to monitor germination and growth based on bacterial size. Spores germinated best in foetal bovine and monkey sera, moderately with human sera and showed limited germination in the presence of rabbit or rat sera. Vegetative bacteria grew best in foetal bovine sera and moderately in rabbit sera. Human and monkey sera supported little growth of vegetative bacteria.  The data suggested sera can have a significant impact on germination and growth of Sterne bacteria.  These data should be considered when conducting in vitro cell culture studies and may aid in interpreting in vivo infection studies. © 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

The rhizosphere microbial community in a multiple parallel mineralization system suppresses the pathogenic fungus Fusarium oxysporum

PubMed Central

Fujiwara, Kazuki; Iida, Yuichiro; Iwai, Takashi; Aoyama, Chihiro; Inukai, Ryuya; Ando, Akinori; Ogawa, Jun; Ohnishi, Jun; Terami, Fumihiro; Takano, Masao; Shinohara, Makoto

2013-01-01

The rhizosphere microbial community in a hydroponics system with multiple parallel mineralization (MPM) can potentially suppress root-borne diseases. This study focused on revealing the biological nature of the suppression against Fusarium wilt disease, which is caused by the fungus Fusarium oxysporum, and describing the factors that may influence the fungal pathogen in the MPM system. We demonstrated that the rhizosphere microbiota that developed in the MPM system could suppress Fusarium wilt disease under in vitro and greenhouse conditions. The microbiological characteristics of the MPM system were able to control the population dynamics of F. oxysporum, but did not eradicate the fungal pathogen. The roles of the microbiological agents underlying the disease suppression and the magnitude of the disease suppression in the MPM system appear to depend on the microbial density. F. oxysporum that survived in the MPM system formed chlamydospores when exposed to the rhizosphere microbiota. These results suggest that the microbiota suppresses proliferation of F. oxysporum by controlling the pathogen's morphogenesis and by developing an ecosystem that permits coexistence with F. oxysporum. PMID:24311557

Development of antimicrobial films for microbiological control of packaged salad.

PubMed

Muriel-Galet, Virginia; Cerisuelo, Josep P; López-Carballo, Gracia; Lara, Marta; Gavara, Rafael; Hernández-Muñoz, Pilar

2012-07-02

The aim of the present work was to characterize the antimicrobial efficiency of films consisting of PP/EVOH structures with oregano essential oil and citral. Both substances are known for their antimicrobial activity based on their interaction with the cell membrane. The films developed were used to pack minimally processed salads, combining modified atmosphere technology to extend shelf-life and active packaging technology to reduce possible microbiological risks. The antimicrobial activity of the films against the pathogenic microorganisms Escherichia coli, Salmonella enterica and Listeria monocytogenes and natural microflora was investigated "in vitro" and also on the food itself. The effect of release of the antimicrobial agent on the sensory characteristics of the salad was also studied. The results showed that antimicrobial activity reduced spoilage flora on the salad as well as inhibited the growth of pathogens in contaminated salads. This effect was greater against Gram-negative bacteria. Sensory studies showed that the package that was most effective and most accepted by customers was the one containing 5% oregano essential oil. Copyright © 2012 Elsevier B.V. All rights reserved.

Is This the Carbapenemase Test We've Been Waiting for? A Multicenter Evaluation of the Modified Carbapenem Inactivation Method.

PubMed

Butler-Wu, Susan M; Abbott, April N

2017-08-01

A plethora of phenotypic methods exist for the detection of carbapenemases; however, clinical laboratories have struggled for years with accurate, objective phenotypic detection of carbapenemase activity in Enterobacteriaceae In this issue of the Journal of Clinical Microbiology , V. M. Pierce et al. (J Clin Microbiol 55:2321-2333, 2017, https://doi.org/10.1128/JCM.00193-17) report on a multicenter evaluation of the modified carbapenem inactivation method (mCIM). The high sensitivity, specificity, reproducibility, and ease of interpretation associated with the mCIM for Enterobacteriaceae will likely lead to its adoption by clinical laboratories. Copyright © 2017 American Society for Microbiology.

A comparison of indexing methods to evaluate quality of soils subjected to different erosion: the role of soil microbiological properties.

NASA Astrophysics Data System (ADS)

Romaniuk, Romina; Lidia, Giuffre; Alejandro, Costantini; Norberto, Bartoloni; Paolo, Nannipieri

2010-05-01

Soil quality assessment is needed to evaluate the soil conditions and sustainability of soil and crop management properties, and thus requires a systematic approach to select and interpret soil properties to be used as indicators. The aim of this work was to evaluate and compare different indexing methods to assess quality of an undisturbed grassland soil (UN), a degraded pasture soil (GL) and a no tilled soil (NT) with four different A horizon depths (25, 23, 19 and 14 cm) reflecting a diverse erosion. Twenty four soil properties were measured from 0 to10 (1) and 10 to 20 cm. (2) and a minimum data set was chosen by multivariate principal component analysis (PCA) considering all measured soil properties together (A), or according to their classification in physical, chemical or microbiological (B) properties. The measured soil properties involved either inexpensive or not laborious standard protocols, to be used in routine laboratory analysis (simple soil quality index - SSQI), or a more laborious, time consuming and expensive protocols to determine microbial diversity and microbial functionality by methyl ester fatty acids (PLFA) and catabolic response profiles (CRP), respectively (complex soil quality index - CSQI). The selected properties were linearly normalized and integrated by the weight additive method to calculate SSQI A, SSQI B, CSQI A and CSQI B indices. Two microbiological soil quality indices (MSQI) were also calculated: the MSQI 1 only considered microbiological properties according to the procedure used for calculating SQI; the MSQI 2 was calculated by considering microbial carbon biomass (MCB), microbial activity (Resp) and functional diversity determined by CPR (E). The soil quality indices were SSQI A = MCB 1 + Particulate Organic Carbon (POC)1 + Mean Weight Diameter (MWD)1; SSQI B = Saturated hydraulic conductivity (K) 1 + Total Organic Carbon (TOC) 1 + MCB 1; CSQI A = MCB 1 + POC 1 + MWD 1; CSQI B = K 1+ TOC 1+ 0.3 * (MCB 1+ i/a +POC 1) + 0,05 * (E + cy/pre), where i/a and cy/pre are the iso/anteiso and cyclopropyl/precursors ratios determined by PLFA; MSQI 1 (0,3 * (MCB 1+ i/a 1 +POC 1) + 0,05 * (E 1+ cy/pre 1) ) and MSQI 2 (MCB 1+Resp 1+ E 1). All the calculated indices differentiated references plots (UN and GL), from those under no tillage (NT) system. Values were similar in NT plots with low erosion levels (NT 25 and 23) but higher than values of plots with high erosion (NT 19 and 14). Soil quality indices constructed by procedure B, (SSQI B and CSQI B) differentiated among the studied plots with the same or higher sensitivity than the other indices and allowed evaluating the impact of soil management practices and erosion on soil physical, chemical and microbiological properties. The lack of indicators representing all soil properties (physical, chemical and biological) in SQI constructed by procedure A could decrease the index sensitivity to changes in management; and the same may happen when physical, chemical and biological properties present different weights into the calculated SQI. The inclusion of CRP and PLFA data in the indices slightly increased or did not increase the index sensitivity (CSQI A and CSQI B). Generally microbiological indices (MSQI 1 and MSQI 2) were highly sensitive to soil erosion. However, we suggest that indices integrating physical, chemical and microbiological properties may give a more complete view of the soil quality than indices only based on measurement of a few microbiological properties.

Microbiological and nutritional quality of the goat meat by-product "sarapatel".

PubMed

Brasil, Luciana; Queiroz, Angela; Silva, Josevan; Bezerra, Taliana; Arcanjo, Narciza; Magnani, Marciane; Souza, Evandro; Madruga, Marta

2014-01-16

Goat "sarapatel" is a product made from blood and viscera. For the first time, the microbiological and nutritional quality of "sarapatel" samples (n=48) sold under different conditions (in street markets, butcher shops, and supermarkets under refrigeration, frozen or at room temperature) was evaluated. Goat "sarapatel" is a nutritive food, with each 100 g providing, on average, 72 g of moisture, 2 g of ash, 18 g of protein, 9 g of lipids, 2 g of carbohydrates, 282 mg of cholesterol, and high amounts of unsaturated fatty acids and essential amino acids. The analysis of the "sarapatel" samples shows that none of them contain Salmonella spp. or L. monocytogenes. High counts (>104) of total coliforms, thermotolerant coliforms, and sulfite-reducing Clostridium were detected, and coagulase-positive Staphylococcus was found in 31.25% of samples. The storage conditions evaluated (refrigeration, frozen or at room temperature) did not affect the physicochemical quality of the "sarapatel"; however, the unsatisfactory microbiological quality indicates that it is necessary to improve the health-sanitary aspects of the processing and sale of this product.

Mycobacterium tuberculosis Arylamine N-Acetyltransferase Acetylates and Thus Inactivates para-Aminosalicylic Acid.

PubMed

Wang, Xude; Yang, Shanshan; Gu, Jing; Deng, Jiaoyu

2016-12-01

Mycobacterium tuberculosis arylamine N-acetyltransferase (TBNAT) is able to acetylate para-aminosalicylic acid (PAS) both in vitro and in vivo as determined by high-performance liquid chromatography (HPLC) and electrospray ionization-mass spectrometry (ESI-MS) techniques. The antituberculosis activity of the acetylated PAS is significantly reduced. As a result, overexpression of TBNAT in M. tuberculosis results in PAS resistance, as determined by MIC tests and drug exposure experiments. Taken together, our results suggest that TBNAT from M. tuberculosis is able to inactivate PAS by acetylating the compound. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Engineered cationic antimicrobial peptides to overcome multidrug resistance by ESKAPE pathogens.

PubMed

Deslouches, Berthony; Steckbeck, Jonathan D; Craigo, Jodi K; Doi, Yohei; Burns, Jane L; Montelaro, Ronald C

2015-02-01

Multidrug resistance constitutes a threat to the medical achievements of the last 50 years. In this study, we demonstrated the abilities of two de novo engineered cationic antibiotic peptides (eCAPs), WLBU2 and WR12, to overcome resistance from 142 clinical isolates representing the most common multidrug-resistant (MDR) pathogens and to display a lower propensity to select for resistant bacteria in vitro compared to that with colistin and LL37. The results warrant an exploration of eCAPs for use in clinical settings. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The novel phage-derived antimicrobial agent HY-133 is active against livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA).

PubMed

Kaspar, Ursula; de Haro Sautto, Jorge A; Molinaro, Sonja; Peters, Georg; Idelevich, Evgeny A; Becker, Karsten

2018-05-07

Livestock-associated, methicillin-resistant Staphylococcus aureus (LA-MRSA) are increasingly migrating from livestock into human and animal health care settings. Alternative substances are wanted to overcome the drawbacks of currently available drugs applied for MRSA eradication. The recombinant bacteriophage endolysin HY-133 has been proven as an active agent against S. aureus Here, the in vitro activity of HY-133 was studied against a large collection of genetically diverse LA-MRSA revealing its high activity against mecA, mecB and mecC LA-MRSA. Copyright © 2018 American Society for Microbiology.

[Proteomics in infectious diseases].

PubMed

Quero, Sara; Párraga-Niño, Noemí; García-Núñez, Marian; Sabrià, Miquel

2016-04-01

Infectious diseases have a high incidence in the population, causing a major impact on global health. In vitro culture of microorganisms is the first technique applied for infection diagnosis which is laborious and time consuming. In recent decades, efforts have been focused on the applicability of "Omics" sciences, highlighting the progress provided by proteomic techniques in the field of infectious diseases. This review describes the management, processing and analysis of biological samples for proteomic research. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Isolation of bacterial extrachromosomal DNA from human dental plaque associated with periodontal disease, using transposon-aided capture (TRACA).

PubMed

Warburton, Philip J; Allan, Elaine; Hunter, Stephanie; Ward, John; Booth, Veronica; Wade, William G; Mullany, Peter

2011-11-01

The human oral cavity is host to a complex microbial community estimated to comprise >700 bacterial species, of which at least half are thought to be not yet cultivable in vitro. To investigate the plasmids present in this community, we used a transposon-aided capture system, which allowed the isolation of plasmids from human oral supra- and subgingival plaque samples. Thirty-two novel plasmids and a circular molecule that could be an integrase-generated circular intermediate were isolated. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Thermal sterilization of heat-sensitive products using high-temperature short-time sterilization.

PubMed

Mann, A; Kiefer, M; Leuenberger, H

2001-03-01

High-temperature short-time (HTST) sterilization with a continuous-flow sterilizer, developed for this study, was evaluated. The evaluation was performed with respect to (a) the chemical degradation of two heat-sensitive drugs in HTST range (140-160 degrees C) and (b) the microbiological effect of HTST sterilization. Degradation kinetics of two heat-sensitive drugs showed that a high peak temperature sterilization process resulted in less chemical degradation for the same microbiological effect than a low peak temperature process. Both drugs investigated could be sterilized with acceptable degradation at HTST conditions. For the evaluation of the microbiological effect, Bacillus stearothermophilus ATCC 7953 spores were used as indicator bacteria. Indicator spore kinetics (D(T), z value, k, and E(a)), were determined in the HTST range. A comparison between the Bigelow model (z value concept) and the Arrhenius model, used to describe the temperature coefficient of the microbial inactivation, demonstrated that the Bigelow model is more accurate in prediction of D(T) values in the HTST range. The temperature coefficient decreased with increasing temperature. The influence of Ca(2+) ions and pH value on the heat resistance of the indicator spores, which is known under typical sterilization conditions, did not change under HTST conditions.

[Physico-chemical and microbiological evaluation of UHT milk commercialized in three Mercosul countries (Brazil, Argentina and Paraguay)].

PubMed

Domareski, Jackson Luiz; Bandiera, Nataly Simões; Sato, Rafael Tamostu; Aragon-Alegro, Lina Casale; de Santana, Elsa Helena Walter

2010-09-01

With the aim to evaluate the physico-chemical and microbiological quality of UHT milk commercialized in three countries of Mercosul, samples of four different brands were acquired in each city (Foz do Iguaçu-Brazil, Puerto Iguazú-Argentina and Ciudad del Este-Paraguay) and submitted to the following analysis: fat content, titratable acidity, milk ethanol stability (with the following ethanol concentrations: 68, 72, 76 and 80%), total dry extract and no fat dry extract, pH, density and freezing point. Counts of mesophilic and psychrotrophic microorganisms were already done. In the physico-chemical evaluation of UHT milk, a significant number of samples were in disagree with the established patterns for fat content, no fat dry extract, density and freezing point. Except one brand from Brazil, milk samples showed stability to 68% ethanol. pH averages of Brazilian milk were in agree with the patterns and highest values were observed in samples acquired on Paraguay. Observing the microbiological analysis, 37.5%, 62.5% and 12.5% of samples acquired from Brazil, Argentina and Paraguay, respectively, showed counts above the established patterns for mesophilic microorganisms. Counts of psychrotrophic microorganisms were in disagree with the established patterns in 50%, 50% and 100% of samples from Brazil, Argentina and Paraguay, respectively.

[Evaluation of hydrocarbon-oxidizing bacteria in port water and of health risks related to harbour activities: port of Otranto (Italy)].

PubMed

De Donno, Antonella; Bagordo, Francesco; Rollo, Maria Concetta; Quattrocchi, Manuela; Campa, Annamaria; Guido, Marcello

2006-01-01

The aim of this study was to evaluate the water quality of the port of Otranto (Italy), through a combined approach which integrates monitoring of traditional microbiological parameters and studying the dynamics of some autochthonous bacterial communities. The fecal contamination indicators, total coliforms, fecal coliforms, and fecal streptococci were measured to evaluate the sanitary aspects, while the presence of organic matter was considered as a parameter strictly related to dumping. In addition, being the port of Otranto especially exposed to hydrocarbon pollution, hydrocarbon-oxidizing bacteria were evaluated. Fecal contamination indicators were consistently found to be below the threshold values set by the Italian legislative decree N. 470/82 for bathing waters, indicating a good microbiological quality of these waters. A higher density of hydrocarbon-oxidizing bacteria was found at mooring and craft transit areas. This parameter was therefore found to be useful for evaluating port water hydrocarbon pollution.

Towards objective hand hygiene technique assessment: validation of the ultraviolet-dye-based hand-rubbing quality assessment procedure.

PubMed

Lehotsky, Á; Szilágyi, L; Bánsághi, S; Szerémy, P; Wéber, G; Haidegger, T

2017-09-01

Ultraviolet spectrum markers are widely used for hand hygiene quality assessment, although their microbiological validation has not been established. A microbiology-based assessment of the procedure was conducted. Twenty-five artificial hand models underwent initial full contamination, then disinfection with UV-dyed hand-rub solution, digital imaging under UV-light, microbiological sampling and cultivation, and digital imaging of the cultivated flora were performed. Paired images of each hand model were registered by a software tool, then the UV-marked regions were compared with the pathogen-free sites pixel by pixel. Statistical evaluation revealed that the method indicates correctly disinfected areas with 95.05% sensitivity and 98.01% specificity. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

A Meta-Analysis of Self-Administered vs Directly Observed Therapy Effect on Microbiologic Failure, Relapse, and Acquired Drug Resistance in Tuberculosis Patients

PubMed Central

Pasipanodya, Jotam G.; Gumbo, Tawanda

2013-01-01

Background Preclinical studies and Monte Carlo simulations have suggested that there is a relatively limited role of adherence in acquired drug resistance (ADR) and that very high levels of nonadherence are needed for therapy failure. We evaluated the superiority of directly observed therapy (DOT) for tuberculosis patients vs self-administered therapy (SAT) in decreasing ADR, microbiologic failure, and relapse in meta-analyses. Methods Prospective studies performed between 1965 and 2012 in which adult patients with microbiologically proven pulmonary Mycobacterium tuberculosis were separately assigned to either DOT or SAT as part of short-course chemotherapy were chosen. Endpoints were microbiologic failure, relapse, and ADR in patients on either DOT or SAT. Results Ten studies, 5 randomized and 5 observational, met selection criteria: 8774 patients were allocated to DOT and 3708 were allocated to SAT. For DOT vs SAT, the pooled risk difference for microbiologic failure was .0 (95% confidence interval [CI], −.01 to .01), for relapse .01 (95% CI, −.03 to .06), and for ADR 0.0 (95% CI, −0.01 to 0.01). The incidence rates for DOT vs SAT were 1.5% (95% CI, 1.3%–1.8%) vs 1.7% (95% CI, 1.2%–2.2%) for microbiologic failure, 3.7% (95% CI, 0.7%–17.6%) vs 2.3% (95% CI, 0.7%–7.2%) for relapse, and 1.5% (95% CI, 0.2%–9.90%) vs 0.9% (95% CI, 0.4%–2.3%) for ADR, respectively. There was no evidence of publication bias. Conclusions DOT was not significantly better than SAT in preventing microbiologic failure, relapse, or ADR, in evidence-based medicine. Resources should be shifted to identify other causes of poor microbiologic outcomes. PMID:23487389

Preferential aerosolization of bacteria in bioaerosols generated in vitro.

PubMed

Perrott, P; Turgeon, N; Gauthier-Levesque, L; Duchaine, C

2017-09-01

Little is known about how bacteria are aerosolized in terms of whether some bacteria will be found in the air more readily than others that are present in the source. This report describes in vitro experiments to compare aerosolization rates (also known as preferential aerosolization) of Gram-positive and Gram-negative bacteria as well as rod- and coccus-shaped bacteria, using two nebulization conditions. A consortium of five bacterial species was aerosolized in a homemade chamber. Aerosols generated with a commercial nebulizer and a homemade bubble-burst aerosol generator were compared. Data suggest that Pseudomonas aeruginosa was preferentially aerosolized in comparison to Moraxella catarrhalis, Lactobacillus paracasei, Staphylococcus aureus and Streptococcus suis, independently of the method of aerosolization. Bacterial integrity of Strep. suis was more preserved compared to other bacteria studied as revealed with PMA-qPCR. We reported the design of an aerosol chamber and bubble-burst generator for the in vitro study of preferential aerosolization. In our setting, preferential aerosolization was influenced by bacterial properties instead of aerosolization mechanism. These findings could have important implications for predicting the composition of bioaerosols in various locations such as wastewater treatment plants, agricultural settings and health care settings. © 2017 The Society for Applied Microbiology.

Microbiological toxicity of tilmicosin on human colonic microflora in chemostats.

PubMed

Hao, Haihong; Yao, Junping; Wu, Qinghua; Wei, Yajing; Dai, Menghong; Iqbal, Zahid; Wang, Xu; Wang, Yulian; Huang, Lingli; Chen, Dongmei; Tao, Yanfei; Liu, Zhenli; Yuan, Zonghui

2015-10-01

To evaluate the microbiological safety of tilmicosin on human intestinal microflora, four chemostat models of healthy human colonic ecosystems were exposed to tilmicosin (0, 0.436, 4.36, and 43.6 μg/mL) for 7 days. Prior to and during drug exposure, three microbiological endpoints were monitored daily including short-chain fatty acids, bacterial counts and macrolide susceptibility. Colonization resistance of each community was determined by 3 successive daily challenges of Salmonella typhimurium. Genes associated with virulence and macrolide resistance in Enterococcus faecalis were determined by PCR. Transcriptional expression of the virulence gene (gelE) in E. faecalis was determined by real-time RT-PCR. Our results showed that different concentrations of tilmicosin did not disrupt the colonization resistance in each chemostat. During exposure to 4.36 and 43.6 μg/mL tilmicosin, the Bacteroides fragilis population was significantly decreased while the proportion of resistant Enterococci increased. After long-term exposure to the highest concentration (43.6 μg/mL) of tilmicosin, the gelE gene was significantly up-regulated in the high-level macrolide resistant strains that also contained the ermB resistance gene. This study was the first of its kind to evaluate the microbiological toxicity of tilmicosin using a chemostat model. These findings also provide new insight into the co-occurrence of macrolide resistance and virulence in E. faecalis under tilmicosin selective pressure. Copyright © 2015 Elsevier Inc. All rights reserved.

Shelf Life of Anchovy Products (Engraulis Encrasicolus): Evaluation of Sensory, Microbiological and Chemical Properties

PubMed Central

Scarano, Luigi; Mormile, Amalia; Barile, Maria; Palma, Giuseppe; Murru, Nicoletta

2014-01-01

Fishery products have always been an important food in Italy. In the past, increased consumption was mainly due to the good quality of the products, easiness of use and their beneficial effects on health. Recently, owing to the national financial crisis, there has been a decline in the consumption of fish. In fact, in 2013, according to data from ISMEA, the consumption of fresh fish suffered a sharp contraction (-5%). This decline also concerns anchovy (Engraulis encrasicolus). This species, partly because of its low price, is a mainstay of traditional Italian food. The aim of this study was to evaluate sensorial, chemical and microbiological properties of anchovy-based (Engraulis encrasicolus) products during storage at 4 and -20°C. Fresh anchovies, obtained from the wholesale fish market of Pozzuoli (Southern Italy) were cut into small pieces and hand-prepared using bread, eggs, cheese and lemon juice. Samples were analysed after 0, 2, 4, 6 and 8 days of storage at 4°C. An aliquot was quickly frozen and analysed after 34 days at -20°C. Sensory assessment, microbiological (specific spoilage organisms, Listeria spp. and Salmonella spp.) and chemical (histamine, total volatile basic nitrogen, trimethylamine, thiobarbituric acid, pH and aw) analyses were performed. Results showed that the shelf life of anchovy products was less than 5 days for the samples stored at 4°C. At -20°C, all anchovies preparations showed good sensory, microbiological and chemical properties for 34 days. PMID:27800315

Evaluation of low-dose irradiation on microbiological quality of white carrots and string beans

NASA Astrophysics Data System (ADS)

Koike, Amanda C. R.; Santillo, Amanda G.; Rodrigues, Flávio T.; Duarte, Renato C.; Villavicencio, Anna Lucia C. H.

2012-08-01

The minimally processed food provided the consumer with a product quality, safety and practicality. However, minimal processing of food does not reduce pathogenic population of microorganisms to safe levels. Ionizing radiation used in low doses is effective to maintain the quality of food, reducing the microbiological load but rather compromising the nutritional values and sensory property. The association of minimal processing with irradiation could improve the quality and safety of product. The purpose of this study was to evaluate the effectiveness of low-doses of ionizing radiation on the reduction of microorganisms in minimally processed foods. The results show that the ionizing radiation of minimally processed vegetables could decontaminate them without several changes in its properties.

Evaluation of proposed Skylab and SSP soap products

NASA Technical Reports Server (NTRS)

Whitmore, F. C.; Durfee, R. L.; Spurlock, J. M.

1973-01-01

Three personal hygiene cleansing agents and one laundry detergent (sodium dodecyl benzene sulfonate), which are all candidates for use on long-duration space missions, were evaluated in terms of dermatological effects on human subjects and effects on microbiological species. None of the four materials exhibited adverse dermatological effects from either skin patch tests of two weeks duration or a simulated Skylab personal hygiene regimen of up to four weeks duration. No significant alterations in skin microflora during the use regimen were found. None of the four materials were found to serve as microbiological support media for the species tested, but a species of air-borne mold was observed to grow rapidly in a neutralized aqueous solution. None of the candidate agents was found to be strongly biocidal.

Microbiological Laboratory Hazard of Bearded Men

PubMed Central

Barbeito, Manuel S.; Mathews, Charles T.; Taylor, Larry A.

1967-01-01

An investigation was conducted to evaluate the hypothesis that a bearded man subjects his family and friends to risk of infection if his beard is contaminated by infectious microorganisms while he is working in a microbiological laboratory. Bearded and unbearded men were tested with Serratia marcescens and Bacillus subtilis var. niger. Contact aerosol transmission from a contaminated beard on a mannequin to a suitable host was evaluated with both Newcastle disease virus and Clostridium botulinum toxin, type A. The experiments showed that beards retained microorganisms and toxin despite washing with soap and water. Although washing reduced the amount of virus or toxin, a sufficient amount remained to produce disease upon contact with a suitable host. Images Fig. 1 Fig. 2 Fig. 3 PMID:4963447

Current and Future Technologies for Microbiological Decontamination of Cereal Grains.

PubMed

Los, Agata; Ziuzina, Dana; Bourke, Paula

2018-06-01

Cereal grains are the most important staple foods for mankind worldwide. The constantly increasing annual production and yield is matched by demand for cereals, which is expected to increase drastically along with the global population growth. A critical food safety and quality issue is to minimize the microbiological contamination of grains as it affects cereals both quantitatively and qualitatively. Microorganisms present in cereals can affect the safety, quality, and functional properties of grains. Some molds have the potential to produce harmful mycotoxins and pose a serious health risk for consumers. Therefore, it is essential to reduce cereal grain contamination to the minimum to ensure safety both for human and animal consumption. Current production of cereals relies heavily on pesticides input, however, numerous harmful effects on human health and on the environment highlight the need for more sustainable pest management and agricultural methods. This review evaluates microbiological risks, as well as currently used and potential technologies for microbiological decontamination of cereal grains. © 2018 Institute of Food Technologists®.

[Role of medium-sized independent laboratories in control of healthcare-associated infection].

PubMed

Anzai, Eiko; Fukui, Toru

2009-05-01

In 2006, the Ministry of Health and Welfare revised the regulations regarding the Medical Service Law. The amendments stipulate that all healthcare institutions are required to implement infection control programs. However, small hospitals and clinics have no clinical microbiology laboratories, whereas medium-sized hospitals have few medical technologists and the outsourcing of microbiology tests to independent laboratories is common. The decreasing number of laboratories and recent outsourcing tendency reflect the increasing commercialization, and, with it, the escalating number of commercially operating chains. Each independent laboratory is responsible for supporting activities related to the surveillance, control, and prevention of healthcare-associated infections in the associated small and medium-sized hospitals. The people responsible for infection control in these hospitals usually do not have a background in microbiology. The evaluation of communication between independent laboratory staff and hospital personnel, and rapid turnaround time of microbiology laboratory test reports are important elements ensuring the quality of independent laboratory work. With the pressures of financial constraints in the Japanese medical insurance system, the development of a cost-effective and practical protocol for quality assurance is a real dilemma.

Effect of storage on the chemical composition, microbiological load, and sensory properties of cassava starch-based custard powder

PubMed Central

Awoyale, Wasiu; Sanni, Lateef O; Shittu, Taofik A; Adegunwa, Mojisola O

2015-01-01

The effect of storage on the chemical, microbiological, and sensory properties of cassava starch-based custard powder (CbCP) blends as mixture of yellow-fleshed cassava root starch (YfCRS) (90–98%) and whole egg powder (WEP) (2–10%) was investigated. These were prepared using central composite rotatable design, and separately packaged in polyvinyl chloride plastic can and stored in storage box (30 ± 2°C). The chemical and microbiological analyses of the stored CbCP were evaluated at 3 weeks intervals, while the sensory property was determined at 6 weeks interval for 24 weeks. The result showed that the protein, fat, and the total-β-carotene contents of the CbCP decreased significantly (P ≤ 0.001) after storage while moisture content and microbiological load increased. All the CbCP sensory attributes were accepted at the end of storage, except taste and color. The CbCP gruel prepared from 94% YfCRS: 0.34% WEP and 90% YfCRS: 2% WEP blends were the most acceptable after storage. PMID:26405528

Effect of storage on the chemical composition, microbiological load, and sensory properties of cassava starch-based custard powder.

PubMed

Awoyale, Wasiu; Sanni, Lateef O; Shittu, Taofik A; Adegunwa, Mojisola O

2015-09-01

The effect of storage on the chemical, microbiological, and sensory properties of cassava starch-based custard powder (CbCP) blends as mixture of yellow-fleshed cassava root starch (YfCRS) (90-98%) and whole egg powder (WEP) (2-10%) was investigated. These were prepared using central composite rotatable design, and separately packaged in polyvinyl chloride plastic can and stored in storage box (30 ± 2°C). The chemical and microbiological analyses of the stored CbCP were evaluated at 3 weeks intervals, while the sensory property was determined at 6 weeks interval for 24 weeks. The result showed that the protein, fat, and the total-β-carotene contents of the CbCP decreased significantly (P ≤ 0.001) after storage while moisture content and microbiological load increased. All the CbCP sensory attributes were accepted at the end of storage, except taste and color. The CbCP gruel prepared from 94% YfCRS: 0.34% WEP and 90% YfCRS: 2% WEP blends were the most acceptable after storage.

Actinobacillus pleuropneumoniae grows as aggregates in the lung of pigs: is it time to refine our in vitro biofilm assays?

PubMed

Tremblay, Yannick D N; Labrie, Josée; Chénier, Sonia; Jacques, Mario

2017-07-01

Actinobacillus pleuropneumoniae causes porcine pleuropneumonia and forms biofilms in vitro on abiotic surfaces; however, presence of biofilms during infections has not been documented. The aim of this study was to use a species-specific fluorescent oligonucleotide probe and confocal microscopy to localize A. pleuropneumoniae in the lungs of two naturally infected pigs. Actinobacillus pleuropneumoniae was detected by fluorescence in situ hybridization and observed to grow as aggregates (~30-45 μm) during a natural infection. As the A. pleuropneumoniae aggregates observed in porcine lungs differed from the biofilms grown on a solid surface obtained in vitro, we designed a new biofilm assay using agarose, a porous substrate, favouring the formation of aggregates. In this study, we described for the first time the mode of growth of A. pleuropneumoniae during a natural infection in pigs. We also propose an in vitro biofilm assay for A. pleuropneumoniae using a porous substrate which allows the formation of aggregates. This assay might be more representative of the in vivo situation, at least in terms of the size of the bacterial aggregates and the presence of a porous matrix, and could potentially be used to test the susceptibility of A. pleuropneumoniae aggregates to antibiotics and disinfectants. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Antifungal properties of organic extracts of eight Cistus L. species against postharvest citrus sour rot.

PubMed

Karim, H; Boubaker, H; Askarne, L; Talibi, I; Msanda, F; Boudyach, E H; Saadi, B; Ait Ben Aoumar, A

2016-01-01

The effectiveness of methanol and chloroform extracts of eight Cistaceae species to control citrus sour rot decay, caused by Geotrichum citri-aurantii, was investigated in both in vitro and in vivo conditions. Methanol extracts of these plant species exhibited more interesting activity against G. citri-aurantii, in both in vitro and in vivo conditions, compared with chloroforme extracts. Under in vitro trials, obtained results showed that methanol extracts of all tested plants revealed a highest significant antifungal activity with inhibition zones that ranged between 12·33 and 16·33 mm in diameter. All tested methanol extracts totally inhibited spore germination when tested at 10 mg ml(-1) . Incidence of sour rot was significantly lowered to 11·11% when fruits were treated with Cistus populifolius and Cistus ladanifer methanol extracts compared with 100% in the control. The disease severity was lowered to 5·19% and 6·04% when fruits were treated with the same methanol extracts respectively. The methanol Cistus extracts had sufficient antifungal activities in vitro and in vivo against G. citri-aurantii to consider its use in the citrus industry after it has been tested under production and natural infection conditions. Such natural products therefore represent a viable alternative approaches for sour rot postharvest management of citrus. © 2015 The Society for Applied Microbiology.

Hyperbaric Oxygen Reduces Aspergillus fumigatus Proliferation In Vitro and Influences In Vivo Disease Outcomes.

PubMed

Dhingra, Sourabh; Buckey, Jay C; Cramer, Robert A

2018-03-01

Recent estimates suggest that more than 3 million people have chronic or invasive fungal infections, causing more than 600,000 deaths every year. Aspergillus fumigatus causes invasive pulmonary aspergillosis (IPA) in patients with compromised immune systems and is a primary contributor to increases in human fungal infections. Thus, the development of new clinical modalities as stand-alone or adjunctive therapy for improving IPA patient outcomes is critically needed. Here we tested the in vitro and in vivo impacts of hyperbaric oxygen (HBO) (100% oxygen, >1 atmosphere absolute [ATA]) on A. fumigatus proliferation and murine IPA outcomes. Our findings indicate that HBO reduces established fungal biofilm proliferation in vitro by over 50%. The effect of HBO under the treatment conditions was transient and fungistatic, with A. fumigatus metabolic activity rebounding within 6 h of HBO treatment being removed. In vivo , daily HBO provides a dose-dependent but modest improvement in murine IPA disease outcomes as measured by survival analysis. Intriguingly, no synergy was observed between subtherapeutic voriconazole or amphotericin B and HBO in vitro or in vivo with daily HBO dosing, though the loss of fungal superoxide dismutase genes enhanced HBO antifungal activity. Further studies are needed to optimize the HBO treatment regimen and better understand the effects of HBO on both the host and the pathogen during a pulmonary invasive fungal infection. Copyright © 2018 American Society for Microbiology.

Effect of cumin essential oil usage on fermentation quality, aerobic stability and in vitro digetibility of alfalfa silage.

PubMed

Turan, Aslı; Önenç, Sibel Soycan

2018-03-02

This study was carried out to determine the effects of cumin essential oil on the silage fermentation, aerobic stability and in vitro digestibility of alfalfa silages. Alfalfa was harvested at early bloom (5 th cutting) stage in October and wilted for about 3 hours. The research was carried out at three groups which were the control group where no additive control was done (CON), cumin essential oil (CMN3) with 300 mg/kg and CMN5 with 500 mg/kg cumin essential oil addition. Alfalfa was ensiled in plastic bags. The packages were stored at 8±2 °C under laboratory conditions. All groups were sampled for physical, chemical and microbiological analysis 120th day after ensiling. At the end of the ensiling period, all silages were subjected to an aerobic stability test for 7 days. In addition, enzimatic solubility of organic matter (ESOM), metabolizable energy (ME) and relative feed value (RFV) of these silages were determined. pH level decreased in the cumin groups compared to CON (P<0.05), thus inhibiting proteolytic enzymes from breaking down proteins into ammonia. In addition, it increased ESOM amount, and concordantly provided an increase of ME contents. Similarly, dry matter intake (DMI) and RFV ratio increased. After opening the silage, it kept its aerobic stability for three days. Cumin essential oil improved fermentation, and affected chemical and microbiological characteristics of silages. Especially the addition of 300 mg/kg cumin provided cell wall fractionation through stimulating the activities of enzymes responsible. It also increased the number and activity of lactic acid bacteri (LAB) through providing a development of LAB.

Effect of an oxygenating agent on oral bacteria in vitro and on dental plaque composition in healthy young adults.

PubMed

Fernandez y Mostajo, Mercedes; van der Reijden, Wil A; Buijs, Mark J; Beertsen, Wouter; Van der Weijden, Fridus; Crielaard, Wim; Zaura, Egija

2014-01-01

Oral bacteria live in symbiosis with the host. Therefore, when mouthwashes are indicated, selective inhibition of taxa contributing to disease is preferred instead of broad-spectrum antimicrobials. The potential selectivity of an oxygenating mouthwash, Ardox-X® (AX), has not been assessed. The aim of this study was to determine the antimicrobial potential of AX and the effects of a twice-daily oral rinse on dental plaque composition. In vitro, 16 oral bacterial strains were tested using agar diffusion susceptibility, minimum inhibitory and minimum bactericidal concentration tests. A pilot clinical study was performed with 25 healthy volunteers. Clinical assessments and microbiological sampling of supragingival plaque were performed at 1 month before the experiment (Pre-exp), at the start of the experiment (Baseline) and after the one-week experimental period (Post-exp). During the experiment individuals used AX mouthwash twice daily in absence of other oral hygiene measures. The microbiological composition of plaque was assessed by 16S rRNA gene amplicon sequencing. AX showed high inter-species variation in microbial growth inhibition. The tested Prevotella strains and Fusobacterium nucleatum showed the highest sensitivity, while streptococci and Lactobacillus acidophilus were most resistant to AX. Plaque scores at Pre-exp and Baseline visits did not differ significantly (p = 0.193), nor did the microbial composition of plaque. During a period of 7-days non-brushing but twice daily rinsing plaque scores increased from 2.21 (0.31) at Baseline to 2.43 (0.39) Post-exp. A significant microbial shift in composition was observed: genus Streptococcus and Veillonella increased while Corynebacterium, Haemophilus, Leptotrichia, Cardiobacterium and Capnocytophaga decreased (p ≤ 0.001). AX has the potential for selective inhibition of oral bacteria. The shift in oral microbiome after 1 week of rinsing deserves further research.

Nucleic Acid Polymers Are Active against Hepatitis Delta Virus Infection In Vitro.

PubMed

Beilstein, Frauke; Blanchet, Matthieu; Vaillant, Andrew; Sureau, Camille

2018-02-15

In this study, an in vitro infection model for the hepatitis delta virus (HDV) was used to evaluate the antiviral effects of phosphorothioate nucleic acid polymers (NAPs) and investigate their mechanism of action. The results show that NAPs inhibit HDV infection at concentrations less than 4 μM in cultures of differentiated human hepatoma cells. NAPs were shown to be active at viral entry but inactive postentry on HDV RNA replication. Inhibition was independent of the NAP nucleotide sequence but dependent on both size and amphipathicity of the polymer. NAP antiviral activity was effective against HDV virions bearing the main hepatitis B virus (HBV) immune escape substitutions (D144A and G145R) and was pangenomic with regard to HBV envelope proteins. Furthermore, similar to immobilized heparin, immobilized NAPs could bind HDV particles, suggesting that entry inhibition was due, at least in part, to preventing attachment of the virus to cell surface glycosaminoglycans. The results document NAPs as a novel class of antiviral compounds that can prevent HDV propagation. IMPORTANCE HDV infection causes the most severe form of viral hepatitis in humans and one of the most difficult to cure. Currently, treatments are limited to long-term administration of interferon at high doses, which provide only partial efficacy. There is thus an urgent need for innovative approaches to identify new antiviral against HDV. The significance of our study is in demonstrating that nucleic acid polymers (NAPs) are active against HDV by targeting the envelope of HDV virions. In an in vitro infection assay, NAP activity was recorded at concentrations less than 4 μM in the absence of cell toxicity. Furthermore, the fact that NAPs could block HDV at viral entry suggests their potential to control the spread of HDV in a chronically HBV-infected liver. In addition, NAP anti-HDV activity was pangenomic with regard to HBV envelope proteins and not circumvented by HBsAg substitutions associated with HBV immune escape. Copyright © 2018 American Society for Microbiology.

In Vitro Evaluation of CBR-2092, a Novel Rifamycin-Quinolone Hybrid Antibiotic: Microbiology Profiling Studies with Staphylococci and Streptococci ▿

PubMed Central

Robertson, Gregory T.; Bonventre, Eric J.; Doyle, Timothy B.; Du, Qun; Duncan, Leonard; Morris, Timothy W.; Roche, Eric D.; Yan, Dalai; Lynch, A. Simon

2008-01-01

We present data from antimicrobial assays performed in vitro that pertain to the potential clinical utility of a novel rifamycin-quinolone hybrid antibiotic, CBR-2092, for the treatment of infections mediated by gram-positive cocci. The MIC90s for CBR-2092 against 300 clinical isolates of staphylococci and streptococci ranged from 0.008 to 0.5 μg/ml. Against Staphylococcus aureus, CBR-2092 exhibited prolonged postantibiotic effects (PAEs) and sub-MIC effects (SMEs), with values of 3.2, 6.5, and >8.5 h determined for the PAE (3× MIC), SME (0.12× MIC), and PAE-SME (3× MIC/0.12× MIC) periods, respectively. Studies of genetically defined mutants of S. aureus indicate that CBR-2092 is not a substrate for the NorA or MepA efflux pumps. In minimal bactericidal concentration and time-kill studies, CBR-2092 exhibited bactericidal activity against staphylococci that was retained against rifampin- or intermediate quinolone-resistant strains, with apparent paradoxical cidal characteristics against rifampin-resistant strains. In spontaneous resistance studies, CBR-2092 exhibited activity consistent with balanced contributions from its composite pharmacophores, with a mutant prevention concentration of 0.12 μg/ml and a resistance frequency of <10−12 determined at 1 μg/ml in agar for S. aureus. Similarly, CBR-2092 suppressed the emergence of preexisting rifamycin resistance in time-kill studies undertaken at a high cell density. In studies of the intracellular killing of S. aureus, CBR-2092 exhibited prolonged bactericidal activity that was superior to the activities of moxifloxacin, rifampin, and a cocktail of moxifloxacin and rifampin. Overall, CBR-2092 exhibited promising activity in a range of antimicrobial assays performed in vitro that pertain to properties relevant to the effective treatment of serious infections mediated by gram-positive cocci. PMID:18443106

Death Becomes Them: Bacterial Community Dynamics and Stilbene Antibiotic Production in Cadavers of Galleria mellonella Killed by Heterorhabditis and Photorhabdus spp.

PubMed Central

Wollenberg, Amanda C.; Slough, Greg; Hoinville, Megan E.

2016-01-01

ABSTRACT Insect larvae killed by entomopathogenic nematodes are thought to contain bacterial communities dominated by a single bacterial genus, that of the nematode's bacterial symbiont. In this study, we used next-generation sequencing to profile bacterial community dynamics in greater wax moth (Galleria mellonella) larvae cadavers killed by Heterorhabditis nematodes and their Photorhabdus symbionts. We found that, although Photorhabdus strains did initially displace an Enterococcus-dominated community present in uninfected G. mellonella insect larvae, the cadaver community was not static. Twelve days postinfection, Photorhabdus shared the cadaver with Stenotrophomonas species. Consistent with this result, Stenotrophomonas strains isolated from infected cadavers were resistant to Photorhabdus-mediated toxicity in solid coculture assays. We isolated and characterized a Photorhabdus-produced antibiotic from G. mellonella cadavers, produced it synthetically, and demonstrated that both the natural and synthetic compounds decreased G. mellonella-associated Enterococcus growth, but not Stenotrophomonas growth, in vitro. Finally, we showed that the Stenotrophomonas strains described here negatively affected Photorhabdus growth in vitro. Our results add an important dimension to a broader understanding of Heterorhabditis-Photorhabdus biology and also demonstrate that interspecific bacterial competition likely characterizes even a theoretically monoxenic environment, such as a Heterorhabditis-Photorhabdus-parasitized insect cadaver. IMPORTANCE Understanding, and eventually manipulating, both human and environmental health depends on a complete accounting of the forces that act on and shape microbial communities. One of these underlying forces is hypothesized to be resource competition. A resource that has received little attention in the general microbiological literature, but likely has ecological and evolutionary importance, is dead/decaying multicellular organisms. Metazoan cadavers, including those of insects, are ephemeral and nutrient-rich environments, where resource competition might shape interspecific macrobiotic and microbiotic interactions. This study is the first to use a next-generation sequencing approach to study the community dynamics of bacteria within a model insect cadaver system: insect larvae parasitized by entomopathogenic nematodes and their bacterial symbionts. By integrating bioinformatic, biochemical, and classic in vitro microbiological approaches, we have provided mechanistic insight into how antibiotic-mediated bacterial interactions may shape community dynamics within insect cadavers. PMID:27451445

Delafloxacin: Place in Therapy and Review of Microbiologic, Clinical and Pharmacologic Properties.

PubMed

Jorgensen, Sarah C J; Mercuro, Nicholas J; Davis, Susan L; Rybak, Michael J

2018-03-31

Delafloxacin (formerly WQ-3034, ABT492, RX-3341) is a novel fluoroquinolone chemically distinct from currently marketed fluoroquinolones with the absence of a protonatable substituent conferring a weakly acidic character to the molecule. This property results in increased intracellular penetration and enhanced bactericidal activity under acidic conditions that characterize the infectious milieu at a number of sites. The enhanced potency and penetration in low pH environments contrast what has been observed for other zwitterionic fluoroquinolones, which tend to lose antibacterial potency under acidic conditions, and may be particularly advantageous against methicillin-resistant Staphylococcus aureus, for which the significance of the intracellular mode of survival is increasingly being recognized. Delafloxacin is also unique in its balanced target enzyme inhibition, a property that likely explains the very low frequencies of spontaneous mutations in vitro. Delafloxacin recently received US Food and Drug Administration approval for the treatment of acute bacterial skin and skin structure infections and is currently being evaluated in a phase 3 trial among patients with community-acquired pneumonia. In the current era of a heightened awareness pertaining to collateral ecologic damage, safety issues and antimicrobial stewardship principles, it is critical to describe the unique properties of delafloxacin and define its potential role in therapy. The purpose of this article is to review available data pertaining to delafloxacin's biochemistry, pharmacokinetic/pharmacodynamics characteristics, in vitro activity and potential for resistance selection as well as current progress in clinical trials to ultimately assist clinicians in selecting patients who will benefit most from the distinctive properties of this agent.

[Responses of the common bean (Phaseolus vulgaris L.) and Rhizobium tropici CIAT899 symbiosystem to induced allelopathy by Ipomoea purpurea L. Roth].

PubMed

Pérez-Peralta, Paulina Janneth; Ferrera-Cerrato, Ronald; Alarcón, Alejandro; Trejo-Téllez, Libia I; Cruz-Ortega, Rocío; Silva-Rojas, Hilda V

2018-06-07

Allelopathy is a phenomenon that involves the production of secondary metabolites that influence the growth of plants and microorganisms; however, this alellopathic effect has been scarcely studied on the rhizobia-legume symbiosis. The aims of this research were 1) to assess the allelopathic potential of aqueous extracts of Ipomoea purpurea L. Roth on seed germination and root length of common bean seedlings (Phaseolus vulgaris L.), 2) to determine its effects on the in vitro growth of Rhizobium tropici CIAT899, and 3) to evaluate the allelopathic potential of I. purpurea on the growth, nodulation and physiology of common bean plants inoculated with R. tropici. After 48h, 15% of the aqueous root extract of I. purpurea stimulated seed germination, whereas 4% of the aqueous shoot extracts stimulated such germination. Both the root or shoot extracts stimulated seed germination and e root length. In vitro growth of R. tropici was inhibited as a result of the application of both aqueous extracts. The presence of I. purpurea negatively affected both the growth and physiological responses of common bean plants, and this effect was attenuated after the inoculation of R. tropici; nevertheless, this allelopathic plant affected root nodulation. Our results suggest that the symbiosis of rhizobia and roots of common bean plants is an important element for attenuating the negative effects caused by the allelopathic plant. Copyright © 2018 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Novel borate glass/chitosan composite as a delivery vehicle for teicoplanin in the treatment of chronic osteomyelitis.

PubMed

Jia, Wei-Tao; Zhang, Xin; Luo, Shi-Hua; Liu, Xin; Huang, Wen-Hai; Rahaman, Mohamed N; Day, Delbert E; Zhang, Chang-Qing; Xie, Zong-Ping; Wang, Jian-Qiang

2010-03-01

Composite materials composed of borate bioactive glass and chitosan (designated BGC) were investigated in vitro and in vivo as a new delivery system for teicoplanin in the treatment of chronic osteomyelitis induced by methicillin-resistant Staphylococcus aureus (MRSA). In vitro, the release of teicoplanin from BGC pellets into phosphate-buffered saline (PBS), as well as its antibacterial activity, were determined. The compressive strength of the pellets was measured after specific immersion times, and the structure of the pellets was characterized using scanning electron microscopy and X-ray diffraction. In vivo, the tibial cavity of New Zealand White rabbits was injected with MRSA strain to induce chronic osteomyelitis, treated by debridement after 4weeks, implanted with teicoplanin-loaded BGC pellets (designated TBGC) or BGC pellets, or injected intravenously with teicoplanin. After 12weeks' implantation, the efficacy of the TBGC pellets for treating osteomyelitis was evaluated using hematological, radiological, microbiological and histological techniques. When immersed in PBS, the TBGC pellets provided a sustained release of teicoplanin, while the surface of the pellets was converted to hydroxyapatite (HA). In vivo, the best therapeutic effect was observed in animals implanted with TBGC pellets, resulting in significantly lower radiological and histological scores, a lower positive rate of MRSA culture, and an excellent bone defect repair, without local or systemic side effects. The results indicate that TBGC pellets are effective in treating chronic osteomyelitis by providing a sustained release of teicoplanin, in addition to participating in bone regeneration. Copyright 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Candida bloodstream infection: a clinical microbiology laboratory perspective.

PubMed

Pongrácz, Júlia; Kristóf, Katalin

2014-09-01

The incidence of Candida bloodstream infection (BSI) has been on the rise in several countries worldwide. Species distribution is changing; an increase in the percentage of non-albicans species, mainly fluconazole non-susceptible C. glabrata was reported. Existing microbiology diagnostic methods lack sensitivity, and new methods need to be developed or further evaluation for routine application is necessary. Although reliable, standardized methods for antifungal susceptibility testing are available, the determination of clinical breakpoints remains challenging. Correct species identification is important and provides information on the intrinsic susceptibility profile of the isolate. Currently, acquired resistance in clinical Candida isolates is rare, but reports indicate that it could be an issue in the future. The role of the clinical microbiology laboratory is to isolate and correctly identify the infective agent and provide relevant and reliable susceptibility data as soon as possible to guide antifungal therapy.

Assessing Clinical Microbiology Practice Guidelines: American Society for Microbiology Ad Hoc Committee on Evidence-Based Laboratory Medicine Practice Guidelines Assessment

PubMed Central

Kirn, Thomas J.; Westblade, Lars F.; Humphries, Romney

2017-01-01

ABSTRACT As part of the American Society for Microbiology (ASM) Evidence-Based Laboratory Medicine Practice Guidelines Committee of the Professional Practice Committee, an ad hoc committee was formed in 2014 to assess guidelines published by the committee using an assessment tool, Appraisal of Guidelines for Research Evaluation II (AGREE II). The AGREE II assessment helps reviewers determine whether published guidelines are robust, transparent, and clear in presenting practice recommendations in a standardized manner. Identifying strengths and weaknesses of practice guidelines by ad hoc assessments helps with improving future guidelines through the participation of key stakeholders. This minireview describes the development of the ad hoc committee and results from their review of several ASM best practices guidelines and a non-ASM practice guideline from the Emergency Nurses Association. PMID:28835476

Integrated assessment of biomarker responses and microbiological analysis of oysters from São Luís Island, Brazil.

PubMed

Ribeiro, E B; Bastos, L S; Galeno, L S; Mendes, R S; Garino, F; Carvalho-Neta, R N F; Costa, F N

2016-12-15

This study was conducted to evaluate the use of biochemical biomarkers and microbiological analysis to identify levels of oyster contamination at different ports in São Luís Island (Maranhão), Brazil. Oysters were analyzed for total coliforms, thermotolerant coliforms, Escherichia coli and Aeromonas spp. In addition, tissue was removed from the digestive gland to determine the glutathione-S-transferase (GST) and catalase (CAT) activity. The highest percentage of microbiological contamination of oyster samples occurred during the rainy season. The activity of GST and catalase in oysters was also higher in the rainy season, coinciding with the greatest abundance of total and thermotolerant coliforms. Among the prospective biomarkers, GST showed the best results for identification of areas with higher levels of contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cadexomer iodine provides superior efficacy against bacterial wound biofilms in vitro and in vivo.

PubMed

Fitzgerald, Daniel J; Renick, Paul J; Forrest, Emma C; Tetens, Shannon P; Earnest, David N; McMillan, Jillian; Kiedaisch, Brett M; Shi, Lei; Roche, Eric D

2017-01-01

Examination of clinical samples indicates bacterial biofilms are present in the majority of chronic wounds, and substantial evidence suggests biofilms contribute significantly to delayed healing. Bacteria in biofilms are highly tolerant of antimicrobials, and little data exist to guide the choice of anti-biofilm wound therapy. Cadexomer iodine (CI) was recently reported to have superior efficacy compared to diverse wound dressings against Pseudomonas aeruginosa biofilms in an ex vivo model. In the current study, the strong performance of CI vs. P. aeruginosa biofilm was confirmed using colony and colony drip-flow in vitro wound biofilm models. Similar in vitro efficacy of CI was also demonstrated against mature Staphylococcus aureus biofilms using the same models. Additionally, the rapid kill of mature S. aureus and P. aeruginosa colony biofilms was visualized by confocal microscopy using Live/Dead fluorescent stains. Superior in vitro efficacy of CI vs. staphylococcal biofilms was further demonstrated against methicillin-resistant S. aureus (MRSA) using multiple biofilm models with log reduction, Live/Dead, and metabolic endpoints. Comparator antimicrobial dressings, including silver-based dressings used throughout and other active agents used in individual models, elucidated only limited effects against the mature biofilms. Given the promising in vitro activity, CI was tested in an established mouse model of MRSA wound biofilm. CI had significantly greater impact on MRSA biofilm in mouse wounds than silver dressings or mupirocin based on Gram-stained histology sections and quantitative microbiology from biopsy samples (>4 log reduction in CFU/g vs. 0.7-1.6, p < 0.0001). The superior efficacy for CI in these in vitro and in vivo models suggests CI topical products may represent a better choice to address established bacterial biofilm in chronic wounds. © 2016 by the Wound Healing Society.

Definite (microbiologically confirmed) tuberculous meningitis: predictors and prognostic impact.

PubMed

Jha, Sneh Kumar; Garg, Ravindra Kumar; Jain, Amita; Malhotra, Hardeep Singh; Verma, Rajesh; Sharma, Praveen Kumar

2015-12-01

Microbiological confirmation cannot be obtained in approximately two-third patients with tuberculous meningitis. In this study, we sought to identify epidemiological, clinical, cerebrospinal fluid, and imaging parameters that could indicate the possibility of microbiological confirmation among patients with suspected tuberculous meningitis. In this prospective observational study, patients with tuberculous meningitis were evaluated for clinical, laboratory (cerebrospinal fluid microscopy, culture, and polymerase chain reaction), and neuroimaging parameters. All patients received anti-tuberculosis drugs and corticosteroids. The patients were followed for a period of 6 months. Among 118 cases of tuberculous meningitis, there were 43 (36 %) definite (microbiologically confirmed) cases, 59 (50 %) probable and 16 (14 %) possible cases. Among 43 definite cases, tuberculosis polymerase chain reaction (PCR) was positive in 42 (35 %) patients, culture was positive in 1 case and microscopy, after Ziehl-Neelsen staining, was positive in 3 cases. Three factors, modified Barthel index score at admission ≤12 (p = 0.008), cerebrospinal fluid total cell count >100/mm(3) (p = 0.016), and basal exudates on imaging (p = 0.015), were significantly associated with definite tuberculous meningitis. Among 20 patients who died within 6 months, 13 belonged to definite tuberculous meningitis group (p < 0.001). Stage III tuberculous meningitis (p = 0.004), baseline-modified Barthel index score ≤12 (p = 0.013), and positive tuberculosis PCR (p = 0.007) were independently associated with poor outcome on multivariate analysis. Severe disability, cerebrospinal fluid cells >100 mm(3), and basal exudates are significantly related to the presence of microbiologically confirmed definite tuberculous meningitis. Microbiologically confirmed tuberculous meningitis is associated with poorer outcome.

Evaluating Potential Health Risks in Relocatable Classrooms.

ERIC Educational Resources Information Center

Katchen, Mark; LaPierre, Adrienne; Charlin, Cary; Brucker, Barry; Ferguson, Paul

2001-01-01

Only limited data exist describing potential exposures to chemical and biological agents when using portable classrooms or outlining how to assess and reduce associated health risks. Evaluating indoor air quality involves examining ventilating rates, volatile organic compounds, and microbiologicals. Open communication among key stakeholders is…

Construction and evaluation of an online microbiology course for nonscience majors.

PubMed

Hughes, Lee

2008-01-01

The development of web-based technologies provides a new method for course delivery. As with any new technique, evaluation is a necessary tool to determine if the method is consistent with expectations. This study describes the conversion of a nonscience majors' microbiology lecture course to online delivery and evaluates the hypothesis that the online course can be as effective as the traditional course. Course examination scores are compared between the face-to-face and online sections over a 3-year period. On all but one of the course examinations, no significant difference is found for those students in these two distinctly different course types. The success rate, as defined by those students earning grades of C or better, is high for both course types, although the traditional course success rate is slightly higher. Student evaluations of the courses are also positive, though some differences are noted. Overall, student performance in the online course is equivalent to that in the traditional course.

Efficiency tests of samplers for microbiological aerosols, a review

NASA Technical Reports Server (NTRS)

Henningson, E.; Faengmark, I.

1984-01-01

To obtain comparable results from studies using a variety of samplers of microbiological aerosols with different collection performances for various particle sizes, methods reported in the literature were surveyed, evaluated, and tabulated for testing the efficiency of the samplers. It is concluded that these samplers were not thoroughly tested, using reliable methods. Tests were conducted in static air chambers and in various outdoor and work environments. Results are not reliable as it is difficult to achieve stable and reproducible conditions in these test systems. Testing in a wind tunnel is recommended.

Microbiological Evaluation of Production Procedures for Frozen Foil Pack Meals at the Central Preparation Facility of the Francis E. Warren Air Force Base

DTIC Science & Technology

1976-01-01

ACT (Continue an revere* side If necessary and Identify by block numbor) Food items produced at F.E. Warren AFB met the microbiological constraints...of SA(Regulation 146-1. A Hazard Analysis (HA) to aid in production guidance was of limited valuedue to a lack of predictability of production...II I UNCLASSIFIED/ it - RUITY CLASSIFICATO FTI PAGE(Wh.n Dal& Emted) I’ FSUMMARY The APC’s of the six raw beef and chicken samples used for foil pack

Thiolated chitosan nanoparticles as an oral delivery system for Amikacin: in vitro and ex vivo evaluations.

PubMed

Atyabi, F; Talaie, F; Dinarvand, R

2009-08-01

The purpose of this study was the synthesis of two thiol conjugated Chitosan polymers, and evaluation of the potential of Thiomer nanoparticle formulation as a carrier for oral delivery system. Mediated by EDAC (Ethylene-3-(3-di-methylaminopropyl)-carbodiimide), either N-acetyl Cysteine (NAC) or N-acetyl D-penicillamine (NAP) were covalently attached to Chitosan. The success of the synthesis was demonstrated by comparing FTIR spectra. Iodometric titration demonstrated that depending on the pH value of the synthesis medium, the Thiomers display 250 +/- 30 microMol and 300 +/- 20 microMol thiol groups per gram of polymer respectively. The interaction between mucin and Thiomers, compared to mucin and Chitosan was studied for assessment of mucoadhesion properties of synthesized polymers. This interaction was determined by the measurement of the amount of mucin adsorbed on Chitosan and the conjugated polymers. Rotating cylinder method demonstrated an average of 20 times improvement in mucoadhesion of Thiomers compared to the unmodified polymer. Chitosan and Thiomer nanoparticles were formulated by two methods; TPP and Sodium Sulfate gelation. SEM micrographs and data achieved by a Malvern nano/zetasizer show nanoparticles formed by TPP gelation have a mean size of 150 +/- 15 nm compared to 300 +/- 25 nm sized nanoparticles obtained by Sodium sulfate gelation. TPP gelation yields smaller, more spherical shaped nanoparticles with a smaller range of size distribution. Amikacin loaded nanoparticles with an average size of 280 nm were prepared by TPP gelation in which disulfide bond formation was achieved by a time dependent oxidation process. In vitro studies were carried out; a recovery rate of 33% and a drug entrapment of 25% were achieved. The amount of release was determined during 18 hr in a carefully prepared media. The permeation time across a biological membrane was observed to be about 150 minutes. Microbiological tests were carried out on two microorganisms; Pseudomona aeruginosa and Staphylococcus aureus to further confirm the amount of Amikacin inside drug loaded nanoparticles.

Potent In Vitro Synergism of Fluconazole and Osthole against Fluconazole-Resistant Candida albicans.

PubMed

Li, De-Dong; Chai, Dong; Huang, Xiao-Wen; Guan, Shao-Xing; Du, Jiang; Zhang, Hao-Yu; Sun, Yan; Jiang, Yuan-Ying

2017-08-01

Osthole is a natural coumarin that exhibits wide biological and pharmacological activities such as neuroprotective, osteogenic, immunomodulation, antitumor, and anti-inflammatory effects. In this study, we investigated the antifungal effects of osthole in vitro A checkerboard microdilution assay showed that osthole has significant synergistic effect with fluconazole against fluconazole-resistant Candida albicans Similar results were obtained from a growth curve assay. Meanwhile, XTT reduction assay demonstrated the synergism of fluconazole and osthole against C. albicans biofilm formation. Microarray results showed that the expression of genes involved in the oxidation-reduction process, energy metabolism, and transportation changed significantly after the combined treatment with fluconazole and osthole, and further results showed that endogenous reactive oxygen species (ROS) was significantly increased in the combination group. In conclusion, these results demonstrate the synergism of fluconazole and osthole against fluconazole-resistant C. albicans and indicate that endogenous ROS augmentation might contribute to the synergism of fluconazole and osthole. Copyright © 2017 American Society for Microbiology.

A method for the quantitative site-specific study of the biochemistry within dental plaque biofilms formed in vivo.

PubMed

Robinson, C; Kirkham, J; Percival, R; Shore, R C; Bonass, W A; Brookes, S J; Kusa, L; Nakagaki, H; Kato, K; Nattress, B

1997-01-01

The study of plaque biofilms in the oral cavity is difficult as plaque removal inevitably disrupts biofilm integrity precluding kinetic studies involving the penetration of components and metabolism of substrates in situ. A method is described here in which plaque is formed in vivo under normal (or experimental) conditions using a collection device which can be removed from the mouth after a specified time without physical disturbance to the plaque biofilm, permitting site-specific analysis or exposure of the undisturbed plaque to experimental conditions in vitro. Microbiological analysis revealed plaque flora which was similar to that reported from many natural sources. Analytical data can be related to plaque volume rather than weight. Using this device, plaque fluoride concentrations have been shown to vary with plaque depth and in vitro short-term exposure to radiolabelled components may be carried out, permitting important conclusions to be drawn regarding the site-specific composition and dynamics of dental plaque.

The Role of In Vitro Susceptibility Testing in the Management of Candida and Aspergillus.

PubMed

Ostrosky-Zeichner, Luis; Andes, David

2017-08-15

Antifungal susceptibility testing has evolved from a research technique to a standardized and well-validated tool for the clinical management of fungal infections and for epidemiological studies. Genetic mutations and phenotypic resistance in vitro have been shown to correlate with clinical outcomes and treatment failures, and this in turn has led to the creation of clinical breakpoints and, more recently, epidemiological cutoff values for clinically relevant fungal pathogens. Resistance mechanisms for Candida and Aspergillus species have been extensively described and their corresponding genetic mutations can now be readily detected. Epidemiological studies have been able to detect the emergence of regional clonal and nonclonal resistance in several countries. The clinical microbiology laboratory is expected to transition from culture and traditional susceptibility testing to molecular methods for detection, identification, and resistance profiling over the next 5-10 years. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

A Glycosylation Mutant of Trypanosoma brucei Links Social Motility Defects In Vitro to Impaired Colonization of Tsetse Flies In Vivo.

PubMed

Imhof, Simon; Vu, Xuan Lan; Bütikofer, Peter; Roditi, Isabel

2015-06-01

Transmission of African trypanosomes by tsetse flies requires that the parasites migrate out of the midgut lumen and colonize the ectoperitrophic space. Early procyclic culture forms correspond to trypanosomes in the lumen; on agarose plates they exhibit social motility, migrating en masse as radial projections from an inoculation site. We show that an Rft1(-/-) mutant needs to reach a greater threshold number before migration begins, and that it forms fewer projections than its wild-type parent. The mutant is also up to 4 times less efficient at establishing midgut infections. Ectopic expression of Rft1 rescues social motility defects and restores the ability to colonize the fly. These results are consistent with social motility reflecting movement to the ectoperitrophic space, implicate N-glycans in the signaling cascades for migration in vivo and in vitro, and provide the first evidence that parasite-parasite interactions determine the success of transmission by the insect host. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

[Bacterium Arthrobacter agilis UMCV2 and diverse amines inhibit in vitro growth of wood-decay fungi].

PubMed

Orozco-Mosqueda, M Del Carmen; Valencia-Cantero, Eduardo; López-Albarrán, Pablo; Martínez-Pacheco, Mauro; Velázquez-Becerra, Crisanto

2015-01-01

The kingdom Fungi is represented by a large number of organisms, including pathogens that deteriorate the main structural components of wood, such as cellulose, hemicellulose and lignin. The aim of our work was to characterize the antifungal activity in Arthrobacter agilis UMCV2 and diverse amines against wood-decaying fungi. Four fungal organisms (designated as UMTM) were isolated from decaying wood samples obtained from a forest in Cuanajo-Michoacán, México. Two of them showed a clear enzymatic activity of cellulases, xylanases and oxido-reducing enzymes and were identified as Hypocrea (UMTM3 isolate) and Fusarium (UMTM13 isolate). In vitro, the amines showed inhibitory effect against UMTM growth and one of the amines, dimethylhexadecylamine (DMA16), exhibited strong potential as wood preventive treatment, against the attack of decaying fungi. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Evaluation of hygiene practices and microbiological status of ready-to-eat vegetable salads in Spanish school canteens.

PubMed

Rodríguez-Caturla, Magdevis Y; Valero, Antonio; Carrasco, Elena; Posada, Guiomar D; García-Gimeno, Rosa M; Zurera, Gonzalo

2012-08-30

This study was conducted in eight Spanish school canteens during the period 2008-2009. Food handlers' practices, kitchen equipment, hygiene/sanitation conditions and handling practices were evaluated using checklists. In parallel, the microbiological quality and safety of ready-to-eat (RTE) vegetable salads were assessed. In addition, food contact surfaces and environmental air quality of different areas were analysed. The study determined the relationship between the microbiological quality of RTE foods and food handling practices, together with the degree of contamination of working surfaces and environmental contamination of processing and distribution areas. Some deficiencies were found regarding the use and change of gloves, hand-washing and cleanliness of working surfaces. The microbial levels detected in the foods examined indicated the absence of pathogens in the samples analysed. Surface counts were higher on cutting boards and faucets, showing insufficient cleanliness procedures. This study constitutes a descriptive analysis of the hygiene/sanitation conditions implemented in food service systems in eight Spanish school canteens. The results should help risk managers to better define control measures to be adopted in order to prevent foodborne infections. Copyright © 2012 Society of Chemical Industry.

Ready-to-eat vegetables production with low-level water chlorination. An evaluation of water quality, and of its impact on end products.

PubMed

D'Acunzo, Francesca; Del Cimmuto, Angela; Marinelli, Lucia; Aurigemma, Caterina; De Giusti, Maria

2012-01-01

We evaluated the microbiological impact of low-level chlorination (1 ppm free chlorine) on the production of ready-to-eat (RTE) vegetables by monitoring the microbiological quality of irrigation and processing water in two production plants over a 4-season period, as well as the microbiological quality of unprocessed vegetables and RTE product. Water samples were also characterized in terms of some chemical and physico-chemical parameters of relevance in chlorination management. Both producers use water with maximum 1 ppm free chlorine for vegetables rinsing, while the two processes differ by the number of washing cycles. Salmonella spp and Campylobacter spp were detected once in two different irrigation water samples out of nine from one producer. No pathogens were found in the vegetable samples. As expected, the procedure encompassing more washing cycles performed slightly better in terms of total mesophilic count (TMC) when comparing unprocessed and RTE vegetables of the same batch. However, data suggest that low-level chlorination may be insufficient in preventing microbial build-up in the washing equipment and/or batch-to batch cross-contamination.

Microbiological stabilization of tiger nuts' milk beverage using ultra-high pressure homogenization. A preliminary study on microbial shelf-life extension.

PubMed

Codina-Torrella, I; Guamis, B; Zamora, A; Quevedo, J M; Trujillo, A J

2018-02-01

Tiger nuts' milk beverages are highly perishable products. For this reason, the interest of food industry for their commercialization makes necessary the application of preservation treatments to prolong their shelf-life. In the current study, the effect of ultra-high pressure homogenization (UHPH) on the microbiological and sensory qualities of tiger nuts' milk beverage was evaluated. Characteristics of UHPH-treated products (at 200 and 300 MPa, with inlet temperature of 40 °C) were compared with those of raw (RP) and conventionally homogenized-pasteurized (H-P) beverages, after treatment and during cold storage at 4 °C. Microbiological quality of beverages was studied by enumerating total counts, psychrotrophic bacteria, lactobacilli, enterobacteria, molds and yeasts, and mesophilic spores. Evolution of color and sensory characteristics of beverages were also determined. Microbiological shelf-life of the tiger nuts' milk beverages was extended from 3 to 25, 30 and 57 days by applying H-P and UHPH treatments at 200 and 300 MPa, respectively. Color of beverages was the only attribute that differentiated UHPH samples from the others, with greater luminosity and whiteness. Hence, UHPH treatments showed to be an alternative to the conventional H-P for obtaining tiger nuts' milk beverages with an improved microbiological shelf-life and good sensorial characteristics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Addressing the key communication barriers between microbiology laboratories and clinical units: a qualitative study.

PubMed

Skodvin, Brita; Aase, Karina; Brekken, Anita Løvås; Charani, Esmita; Lindemann, Paul Christoffer; Smith, Ingrid

2017-09-01

Many countries are on the brink of establishing antibiotic stewardship programmes in hospitals nationwide. In a previous study we found that communication between microbiology laboratories and clinical units is a barrier to implementing efficient antibiotic stewardship programmes in Norway. We have now addressed the key communication barriers between microbiology laboratories and clinical units from a laboratory point of view. Qualitative semi-structured interviews were conducted with 18 employees (managers, doctors and technicians) from six diverse Norwegian microbiological laboratories, representing all four regional health authorities. Interviews were recorded and transcribed verbatim. Thematic analysis was applied, identifying emergent themes, subthemes and corresponding descriptions. The main barrier to communication is disruption involving specimen logistics, information on request forms, verbal reporting of test results and information transfer between poorly integrated IT systems. Furthermore, communication is challenged by lack of insight into each other's area of expertise and limited provision of laboratory services, leading to prolonged turnaround time, limited advisory services and restricted opening hours. Communication between microbiology laboratories and clinical units can be improved by a review of testing processes, educational programmes to increase insights into the other's area of expertise, an evaluation of work tasks and expansion of rapid and point-of-care test services. Antibiotic stewardship programmes may serve as a valuable framework to establish these measures. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.

Addressing the key communication barriers between microbiology laboratories and clinical units: a qualitative study

PubMed Central

Skodvin, Brita; Aase, Karina; Brekken, Anita Løvås; Charani, Esmita; Lindemann, Paul Christoffer; Smith, Ingrid

2017-01-01

Abstract Background Many countries are on the brink of establishing antibiotic stewardship programmes in hospitals nationwide. In a previous study we found that communication between microbiology laboratories and clinical units is a barrier to implementing efficient antibiotic stewardship programmes in Norway. We have now addressed the key communication barriers between microbiology laboratories and clinical units from a laboratory point of view. Methods Qualitative semi-structured interviews were conducted with 18 employees (managers, doctors and technicians) from six diverse Norwegian microbiological laboratories, representing all four regional health authorities. Interviews were recorded and transcribed verbatim. Thematic analysis was applied, identifying emergent themes, subthemes and corresponding descriptions. Results The main barrier to communication is disruption involving specimen logistics, information on request forms, verbal reporting of test results and information transfer between poorly integrated IT systems. Furthermore, communication is challenged by lack of insight into each other’s area of expertise and limited provision of laboratory services, leading to prolonged turnaround time, limited advisory services and restricted opening hours. Conclusions Communication between microbiology laboratories and clinical units can be improved by a review of testing processes, educational programmes to increase insights into the other’s area of expertise, an evaluation of work tasks and expansion of rapid and point-of-care test services. Antibiotic stewardship programmes may serve as a valuable framework to establish these measures. PMID:28633405

Single nucleotide polymorphism in IL1B is associated with infection risk in paediatric acute myeloid leukaemia.

PubMed

Sung, L; Dix, D; Cellot, S; Gillmeister, B; Ethier, M C; Roslin, N M; Johnston, D L; Feusner, J; Mitchell, D; Lewis, V; Aplenc, R; Yanofsky, R; Portwine, C; Price, V; Zelcer, S; Silva, M; Bowes, L; Michon, B; Stobart, K; Traubici, J; Allen, U; Beyene, J; den Hollander, N; Paterson, A D

2016-06-01

We evaluated single nucleotide polymorphisms (SNPs) associated with infection risk in children with newly diagnosed acute myeloid leukaemia (AML). We conducted a multicentre, prospective cohort study that included children aged ≤18 years with de novo AML. DNA was isolated from blood lymphocytes or buccal swabs, and candidate gene SNP analysis was conducted. Primary outcome was the occurrence of microbiologically documented sterile site infection during chemotherapy. Secondary outcomes were Gram-positive and -negative infections, viridans group streptococcal infection and proven/probable invasive fungal infection. Interpretation was guided by consistency in risk alleles and microbiologic agent with previous literature. Over the study period 254 children and adolescents with AML were enrolled. Overall, 190 (74.8%) had at least one sterile site microbiologically documented infection. Among the 172 with inferred European ancestry and DNA available, nine significant associations were observed; two were consistent with previous literature. Allele A at IL1B (rs16944) was associated with decreased microbiologically documented infection, and allele G at IL10 (rs1800896) was associated with increased risk of Gram-positive infection. We identified SNPs associated with infection risk in paediatric AML. Genotype may provide insight into mechanisms of infection risk that could be used for supportive-care novel treatments. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Evaluation of Pharmacist Impact on Culture Review Process for Patients Discharged From the Emergency Department.

PubMed

Santiago, Ruben D; Bazan, Jose A; Brown, Nicole V; Adkins, Eric J; Shirk, Mary Beth

2016-10-01

Background: Accurate and timely review of microbiological test results is a core component of antimicrobial stewardship. There is documented success of these programs in the inpatient setting; however, emergency department (ED) patients are typically not included in these initiatives. Objectives: To assess the impact of an emergency medicine pharmacist (EMP)-facilitated review process of positive microbiological test results from patients discharged from the ED as measured by time to positive result review and number of indicated interventions completed. Methods: This was a retrospective study that compared EMP-facilitated to ED charge nurse (CN)-facilitated physician review of randomly selected positive microbiological test results. Groups were compared concurrently within the time frame of July 1, 2012 through December 31, 2012. Results: One hundred seventy-eight positive microbiological test results were included (EMP, n = 91; CN, n = 87). The median (IQR) time to initial review was 3 (1.0-6.3) hours for the EMP and 2 (0.3-5.5) hours for the CN group ( p = .35). Four percent (1/25) of indicated interventions were not completed in the EMP group versus 47% (14/30) in the CN group ( p = .0004). Conclusion: An EMP was significantly less likely to miss an intervention when indicated with no difference in time to review of positive microbiological results. These findings support the role of the EMP in antimicrobial stewardship in the ED.

Biocompatibility and anti-microbiological activity characterization of novel coatings for dental implants: A primer for non-biologists

NASA Astrophysics Data System (ADS)

Monsees, Thomas

2016-08-01

With regard to biocompatibility, the cardinal requirement for dental implants and other medical devices that are in long-term contact with tissue is that the material does not cause any adverse effect to the patient. To warrant stability and function of the implant, proper osseointegration is a further prerequisite. Cells interact with the implant surface as the interface between bulk material and biological tissue. Whereas structuring, deposition of a thin film or other modifications of the surface are crucial parameters in determining favorable adhesion of cells, corrosion of metal surfaces and release of ions can affect cell viability. Both parameters are usually tested using in vitro cytotoxicity and adhesion assays with bone or fibroblasts cells. For bioactive surface modifications, further tests should be considered for biocompatibility evaluation. Depending on the type of modification, this may include analysis of specific cell functions or the determination of antimicrobial activities. The latter is of special importance as bacteria and yeast present in the oral cavity can be introduced during the implantation process and this may lead to chronic infections and implant failure. An antimicrobial coating of the implant is a way to avoid that. This review describes the essential biocompatibility assays for evaluation of new implant materials required by ISO 10993 and also gives an overview on recent test methods for specific coatings of dental implants.

In vitro inhibitory activity of probiotic products against oral Candida species.

PubMed

Zhao, C; Lv, X; Fu, J; He, C; Hua, H; Yan, Z

2016-07-01

To evaluate the inhibitory activity of probiotics against oral Candida species. Four commercial probiotic products were screened. Bacillus subtilis R0179 was found to have a significant antifungal effect. Bacillus subtilis-Candida interactions were evaluated using disc diffusion tests, confocal laser scanning microscopy, scanning electron microscopy and interaction with engineered human oral mucosa tissue. Bacillus subtilis exhibited clear zones of inhibition for Candida albicans and Candida parapsilosis but not for Candida krusei. A remarkable reduction in the number of Candida cells and abundant Candida cell death were visualized with confocal laser scanning microscopy. Shrinkage and deformation of Candida cells was observed using scanning electron microscopy. Culture of C. albicans on engineered human oral mucosa tissues resulted in the presence of a large number of yeast cells on the tissue surface and the development of large-scale tissue damage. However, comparatively fewer Candida cells were observed on B. subtilis-treated tissues. We also use ultra performance liquid chromatography/time of flight mass spectrometry (UPLC/TOF MS) to explore the preliminary antifungal mechanism of B. subtilis R0179 and to detect that whether it can secrete an antifungal agent, Iturin A. Bacillus subtilis R0179 exhibits a significant inhibitory effect on the growth of Candida species. Bacillus subtilis has the potential to be used in the prevention or treatment of oral candidiasis. © 2016 The Society for Applied Microbiology.

Evaluation of syndromic patient management algorithm for urethral discharge.

PubMed

Djajakusumah, T; Sudigdoadi, S; Keersmaekers, K; Meheus, A

1998-06-01

To determine feasibility, validity, and cost effectiveness of the syndromic approach to male patients with urethral discharge in Bandung, Indonesia. The WHO algorithm on urethral discharge with no microscopy available was evaluated. Patients presented with a complaint of urethral discharge and if discharge was confirmed the algorithm was applied. Treatment covered gonococcal and chlamydial infection (ciprofloxacin 500 mg single oral dose plus doxycycline 100 mg, twice daily orally for 7 days). The gold standard for validation was gonococcal culture and chlamydia antigen detection. 140 male patients with a complaint of urethral discharge were enrolled; 119 had confirmed discharge and entered the decision tree: 107 were followed and 104 (97%) were clinically cured. Of the three patients with persistent discharge, one had a purulent urethral discharge, diagnosed as gonococcal urethritis and he was probably reinfected; two patients had a serous discharge and microbiological tests were negative. Overall, 106 out of 107 patients (99%) were microbiologically cured. Sensitivity of the algorithm is 100% and its positive predictive value (PPV) is 75% or 97% if validated against gold standard microbiological tests or Gram stain, respectively. Cost per patient is rupiah (Rp)5.894 ($US2.56) for the algorithm compared with Rp43.024 ($18.70) for full microbiological diagnosis. The cost estimate for an algorithm of urethral discharge with microscopy available is Rp6.432 ($2.80) The "symptom and sign" algorithm is fully adapted to the prevailing situation in primary healthcare settings, is acceptable to healthcare workers and patients (who are effectively treated at their first visit), is highly cost effective, is 100% sensitive (no false negatives, which is not the case with microbiological diagnosis), and has a high PPV, between 75% and 97%. It is an excellent patient management tool and a sound basis for partner notification so that it should have a major impact on STD/HIV control and prevention in both men and women.

Combination of essential oil compounds and phenolic acids against Escherichia coli O157:H7 in vitro and in dry-fermented sausage production.

PubMed

Meira, Natan V B; Holley, Richard A; Bordin, Keliani; Macedo, Renata E F de; Luciano, Fernando B

2017-11-02

Escherichia coli O157:H7 is a foodborne pathogen that causes hemorrhagic colitis and hemolytic uremic syndrome. The low dose of infection and severity of the disease represent a concern to public health. Natural compounds have been widely applied as food additives to replace synthetic preservatives. The aim of this study was to determine the efficiency of essential oil compounds (EOCs) in combination with phenolic acids (PA) in vitro and in dry-fermented sausage production. Minimum Inhibitory Concentration (MIC) and Fractional Inhibitory Concentration index (FIC index ) were determined for a 5-strain mixture of E. coli O157:H7. Batches of sausage tainted with E. coli O157:H7 were produced using Pediococcus pentosaceus UM 116P and Staphylococcus carnosus UM 123M as starter cultures. The best combination of EOCs and PAs found in vitro was used as an additive. Chemical-physical and microbiological analyses were evaluated weekly from day 0 to 35 after production. Sensory evaluation (texture, odor, flavor, appearance and overall evaluation) of E. coli-free sausages was conducted using a 9-point hedonic scale with 56 untrained volunteers. The MIC values of allyl isothiocyanate (AITC), carvacrol (CAR), ferulic acid (FA), o-coumaric acid (CA) and p-hydroxybenzoic acid (AHB) were, respectively, 0.25; 1.3; 5.12; 18.27; and 37mM. AITC combined with CA had a synergistic effect (FIC index =0.25) and together they were applied in the production of dry fermented sausage at concentrations of 10× FIC and 20× FIC. A w had no significant difference among treatments, whereas the pH of 10× FIC and 20× FIC were higher than the control. E. coli O157:H7 was reduced by >5logCFU/g with 20× FIC after 21d, and by 2.8logCFU/g with 10× FIC after 35d. Sensory analysis showed that the combination of AITC and ο-coumaric acid in both treatments presented lower scores in the 5 categories when compared to the control, but none of the parameters received a negative score. This study demonstrated that the combination of AITC and ο-coumaric acid at 20× FIC reduced E. coli O157:H7 in compliance with the North American legislation, but adjustments in the dose are necessary to improve the sensory characteristics of the final product. Copyright © 2017 Elsevier B.V. All rights reserved.

In Vitro Activity of Delafloxacin Tested against Isolates of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

PubMed

Flamm, Robert K; Rhomberg, Paul R; Huband, Michael D; Farrell, David J

2016-10-01

Delafloxacin, an investigational anionic fluoroquinolone, is active against a broad range of Gram-positive and Gram-negative bacteria. In this study, 200 Streptococcus pneumoniae (plus 30 levofloxacin-resistant isolates), 200 Haemophilus influenzae, and 100 Moraxella catarrhalis isolates selected primarily from the United States (2014) were tested against delafloxacin and comparator agents. Delafloxacin was the most potent agent tested. MIC50 and MIC90 values against all S. pneumoniae isolates were 0.008 and 0.015 μg/ml. Delafloxacin susceptibility was not affected by β-lactamase status against H. influenzae and M. catarrhalis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Microbiological and experimental-histological investigations of lunar samples returned by the Lunar 16 automatic station

NASA Technical Reports Server (NTRS)

Kaulen, D. R.; Bulatova, T. I.; Fridenshteyn, A. Y.; Skvortsova, Y. B.

1974-01-01

Lunar surface material was studied for its content of viable microorganisms (aerobic and anaerobic, fungi, and viruses); the effect of the lunar surface material on the growth of microorganisms and its interaction with somatic cells of mammals was also observed. No viable microorganisms were detected; the samples exhibited neither stimulant or inhibitory action on the growth of microorganisms, and also showed no cytopathogenic action on tissue cultures. A suspension of lunar surface material particles was not toxic when parenterally administered to certain laboratory animals. The particles were subjected to intense phagocytosis by connective tissue cells in vivo and in vitro.

Multicenter Comparison of the Etest and EUCAST Methods for Antifungal Susceptibility Testing of Candida Isolates to Micafungin.

PubMed

Bougnoux, M-E; Dannaoui, E; Accoceberry, I; Angoulvant, A; Bailly, E; Botterel, F; Chevrier, S; Chouaki, T; Cornet, M; Dalle, F; Datry, A; Dupuis, A; Fekkar, A; Gangneux, J P; Guitard, J; Hennequin, C; Le Govic, Y; Le Pape, P; Maubon, D; Ranque, S; Sautour, M; Sendid, B; Chandenier, J

2016-08-01

In vitro susceptibility of 933 Candida isolates, from 16 French hospitals, to micafungin was determined using the Etest in each center. All isolates were then sent to a single center for determination of MICs by the EUCAST reference method. Overall essential agreement between the two tests was 98.5% at ±2 log2 dilutions and 90.2% at ±1 log2 dilutions. Categorical agreement was 98.2%. The Etest is a valuable alternative to EUCAST for the routine determination of micafungin MICs in medical mycology laboratories. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

In vivo and in vitro evaluation of tissue colonization and survival capacity of Salmonella Oranienburg in laying hens.

PubMed

Babu, Uma S; Proszkowiec-Weglarz, Monika; Sharma, Girdhari M; Pereira, Marion; Balan, Kannan V

2018-05-18

Salmonella enterica serovar Oranienburg (SO) was linked to a human salmonellosis outbreak in the Midwest in 2015 and 2016 from consumption of eggs. However, unlike Salmonella enterica serovar Enteritidis (SE), little is known regarding the potential of SO to colonize in laying hens and contaminate eggs. We used in vivo and in vitro models to evaluate tissue colonization and survival capacity of SO. Twenty eight-week-old laying hens were each challenged with an oral dose of approximately 107 (n = 92) or 109 (n = 96) colony-forming units (CFU) in 1 mL saline and evaluated after 1, 2, and 4 wk. Standard microbiological methods with pre-enrichment and enrichment in selective media were used for detection of SO in tissues, egg shell wash, internal egg contents, and excreta. Peak colonization of spleen (86.9%), ovaries (31.6%), upper oviduct (15.8%), and lower oviduct (34.3%) was detected between 1 and 2 wk post-infection (pi), while at 4 wk SO was only recovered from spleens (25%). Salmonella enterica serovar Oranienburg was not recovered from internal egg contents. However, the presence of SO on egg shells was seen when there were traces of excreta. Shedding in excreta was found in 92 and 100% birds gavaged with 107 and 109 CFU at 2 wk pi, respectively. The invasion and proliferation of SO in ovarian granulosa cells (GC) was compared to that of SE, and while the invasion of SO into GC was comparable to SE, proliferation of SO was significantly lower (P < 0.05). The infective potential of SO was also assessed by enumerating survival in egg white over 4 wk under refrigerated conditions, resulting in 65% survival at 4 wk. Overall, our data suggested that SO infection in layers did not result in egg contamination via vertical transmission, and colonization of egg-forming tissues was limited to 2 wk pi. Survival within GC and egg white demonstrates the ability of SO to withstand antibacterial factors and the potential of SO to penetrate the yolk.

Inhaled Antibiotics for Gram-Negative Respiratory Infections.

PubMed

Wenzler, Eric; Fraidenburg, Dustin R; Scardina, Tonya; Danziger, Larry H

2016-07-01

Gram-negative organisms comprise a large portion of the pathogens responsible for lower respiratory tract infections, especially those that are nosocomially acquired, and the rate of antibiotic resistance among these organisms continues to rise. Systemically administered antibiotics used to treat these infections often have poor penetration into the lung parenchyma and narrow therapeutic windows between efficacy and toxicity. The use of inhaled antibiotics allows for maximization of target site concentrations and optimization of pharmacokinetic/pharmacodynamic indices while minimizing systemic exposure and toxicity. This review is a comprehensive discussion of formulation and drug delivery aspects, in vitro and microbiological considerations, pharmacokinetics, and clinical outcomes with inhaled antibiotics as they apply to disease states other than cystic fibrosis. In reviewing the literature surrounding the use of inhaled antibiotics, we also highlight the complexities related to this route of administration and the shortcomings in the available evidence. The lack of novel anti-Gram-negative antibiotics in the developmental pipeline will encourage the innovative use of our existing agents, and the inhaled route is one that deserves to be further studied and adopted in the clinical arena. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Diet-induced changes of redox potential underlie compositional shifts in the rumen archaeal community.

PubMed

Friedman, Nir; Shriker, Eran; Gold, Ben; Durman, Thomer; Zarecki, Raphy; Ruppin, Eytan; Mizrahi, Itzhak

2017-01-01

Dietary changes are known to affect gut community structure, but questions remain about the mechanisms by which diet induces shifts in microbiome membership. Here, we addressed these questions in the rumen microbiome ecosystem - a complex microbial community that resides in the upper digestive tract of ruminant animals and is responsible for the degradation of the ingested plant material. Our dietary intervention experiments revealed that diet affects the most abundant taxa within the microbiome and that a specific group of methanogenic archaea of the order Methanomicrobiales is highly sensitive to its changes. Using metabolomic analyses together with in vitro microbiology approaches and whole-genome sequencing of Methanomicrobium mobile, a key species within this group, we identified that redox potential changes with diet and is the main factor that causes these dietary induced alternations in this taxa's abundance. Our genomic analysis suggests that the redox potential effect stems from a reduced number of anti-reactive oxygen species proteins coded in this taxon's genome. Our study highlights redox potential as a pivotal factor that could serve as a sculpturing force of community assembly within anaerobic gut microbial communities. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

Evaluation of two recommended disinfection methods for cleaning cloths used in food services of southern Brazil

PubMed Central

Bartz, Sabrina; Tondo, Eduardo Cesar

2013-01-01

In the State of Rio Grande do Sul (RS), Southern Brazil, a good manufacturing practices regulation was published recommending two disinfection methods for cleaning cloths used in food services. The aim of the present study was to evaluate the efficacy of those methods. Cleaning cloths were sampled without prior notice at food services, on common working days. For the analyses, the cloths were divided in two sub-samples, being one of them microbiologically analyzed. The second sub-sample was further divided in two pieces and submitted to hand washing for two minutes. After that, one piece was boiled in water for 15 min and the other one was soaked in a 200 ppm sodium hypochlorite solution for 15 min. Both pieces of cloth were submitted to microbiological analyses. Cleaning cloths presented total aerobic mean counts of 6.9 ± 6.7 log/cm2. All cleaning cloths presented coliform contamination, and 40% demonstrated mean counts of 6.2 ± 5.6 log/cm2. Presumptive S. aureus mean counts of 5.5 ± 4.9 log/cm2 were found. No statistic correlation was observed among the number of meals served daily in the food services and the microbiological contamination levels. After washing and disinfection, microbiological counts were significantly (p < 0.05) reduced by both methods, achieving an approximately 5 log reduction. The reductions achieved by the sodium hypochlorite soaking method and the boiling method were not significantly different. Thus, it was possible to conclude that both recommended methods were suitable to disinfect cleaning cloths used in food services. PMID:24516443

Rapid Accurate Identification of Tuberculous Meningitis Among South African Children Using a Novel Clinical Decision Tool.

PubMed

Goenka, Anu; Jeena, Prakash M; Mlisana, Koleka; Solomon, Tom; Spicer, Kevin; Stephenson, Rebecca; Verma, Arpana; Dhada, Barnesh; Griffiths, Michael J

2018-03-01

Early diagnosis of tuberculous meningitis (TBM) is crucial to achieve optimum outcomes. There is no effective rapid diagnostic test for use in children. We aimed to develop a clinical decision tool to facilitate the early diagnosis of childhood TBM. Retrospective case-control study was performed across 7 hospitals in KwaZulu-Natal, South Africa (2010-2014). We identified the variables most predictive of microbiologically confirmed TBM in children (3 months to 15 years) by univariate analysis. These variables were modelled into a clinical decision tool and performance tested on an independent sample group. Of 865 children with suspected TBM, 3% (25) were identified with microbiologically confirmed TBM. Clinical information was retrieved for 22 microbiologically confirmed cases of TBM and compared with 66 controls matched for age, ethnicity, sex and geographical origin. The 9 most predictive variables among the confirmed cases were used to develop a clinical decision tool (CHILD TB LP): altered Consciousness; caregiver HIV infected; Illness length >7 days; Lethargy; focal neurologic Deficit; failure to Thrive; Blood/serum sodium <132 mmol/L; CSF >10 Lymphocytes ×10/L; CSF Protein >0.65 g/L. This tool successfully classified an independent sample of 7 cases and 21 controls with a sensitivity of 100% and specificity of 90%. The CHILD TB LP decision tool accurately classified microbiologically confirmed TBM. We propose that CHILD TB LP is prospectively evaluated as a novel rapid diagnostic tool for use in the initial evaluation of children with suspected neurologic infection presenting to hospitals in similar settings.

Microbiological and clinical effects of probiotics and antibiotics on nonsurgical treatment of chronic periodontitis: a randomized placebo- controlled trial with 9-month follow-up

PubMed Central

Morales, Alicia; Gandolfo, Alessandro; Bravo, Joel; Carvajal, Paola; Silva, Nora; Godoy, Claudia; Garcia-Sesnich, Jocelyn; Hoare, Anilei; Diaz, Patricia; Gamonal, Jorge

2018-01-01

ABSTRACT Objective The aim of this double-blind, placebo-controlled and parallel- arm randomized clinical trial was to evaluate the effects of Lactobacillus rhamnosus SP1-containing probiotic sachet and azithromycin tablets as an adjunct to nonsurgical therapy in clinical parameters and in presence and levels of Tannerella forsythia, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Material and Methods Forty-seven systemically healthy volunteers with chronic periodontitis were recruited and monitored clinically and microbiologically at baseline for 3, 6 and 9 months after therapy. Subgingival plaque samples were collected from four periodontal sites with clinical attachment level ≥1 mm, probing pocket depth ≥4 mm and bleeding on probing, one site in each quadrant. Samples were cultivated and processed using the PCR technique. Patients received nonsurgical therapy including scaling and root planing (SRP) and were randomly assigned to a probiotic (n=16), antibiotic (n = 16) or placebo (n = 15) group. L. rhamnosus SP1 was taken once a day for 3 months. Azithromycin 500mg was taken once a day for 5 days. Results All groups showed improvements in clinical and microbiological parameters at all time points evaluated. Probiotic and antibiotic groups showed greater reductions in cultivable microbiota compared with baseline. The placebo group showed greater reduction in number of subjects with P. gingivalis compared with baseline. However, there were no significant differences between groups. Conclusions The adjunctive use of L. rhamnosus SP1 sachets and azithromycin during initial therapy resulted in similar clinical and microbiological improvements compared with the placebo group. PMID:29364340

Evaluation of an interactive, case-based review session in teaching medical microbiology.

PubMed

Blewett, Earl L; Kisamore, Jennifer L

2009-08-27

Oklahoma State University-Center for Health Sciences (OSU-CHS) has replaced its microbiology wet laboratory with a variety of tutorials including a case-based interactive session called Microbial Jeopardy!. The question remains whether the time spent by students and faculty in the interactive case-based tutorial is worthwhile? This study was designed to address this question by analyzing both student performance data and assessing students' perceptions regarding the tutorial. Both quantitative and qualitative data were used in the current study. Part One of the study involved assessing student performance using archival records of seven case-based exam questions used in the 2004, 2005, 2006, and 2007 OSU-CHS Medical Microbiology course. Two sample t-tests for proportions were used to test for significant differences related to tutorial usage. Part Two used both quantitative and qualitative means to assess student's perceptions of the Microbial Jeopardy! session. First, a retrospective survey was administered to students who were enrolled in Medical Microbiology in 2006 or 2007. Second, responses to open-ended items from the 2008 course evaluations were reviewed for comments regarding the Microbial Jeopardy! session. Both student performance and student perception data support continued use of the tutorials. Quantitative and qualitative data converge to suggest that students like and learn from the interactive, case-based session. The case-based tutorial appears to improve student performance on case-based exam questions. Additionally, students perceived the tutorial as helpful in preparing for exam questions and reviewing the course material. The time commitment for use of the case-based tutorial appears to be justified.

Evaluation of an interactive, case-based review session in teaching medical microbiology

PubMed Central

Blewett, Earl L; Kisamore, Jennifer L

2009-01-01

Background Oklahoma State University-Center for Health Sciences (OSU-CHS) has replaced its microbiology wet laboratory with a variety of tutorials including a case-based interactive session called Microbial Jeopardy!. The question remains whether the time spent by students and faculty in the interactive case-based tutorial is worthwhile? This study was designed to address this question by analyzing both student performance data and assessing students' perceptions regarding the tutorial. Methods Both quantitative and qualitative data were used in the current study. Part One of the study involved assessing student performance using archival records of seven case-based exam questions used in the 2004, 2005, 2006, and 2007 OSU-CHS Medical Microbiology course. Two sample t-tests for proportions were used to test for significant differences related to tutorial usage. Part Two used both quantitative and qualitative means to assess student's perceptions of the Microbial Jeopardy! session. First, a retrospective survey was administered to students who were enrolled in Medical Microbiology in 2006 or 2007. Second, responses to open-ended items from the 2008 course evaluations were reviewed for comments regarding the Microbial Jeopardy! session. Results Both student performance and student perception data support continued use of the tutorials. Quantitative and qualitative data converge to suggest that students like and learn from the interactive, case-based session. Conclusion The case-based tutorial appears to improve student performance on case-based exam questions. Additionally, students perceived the tutorial as helpful in preparing for exam questions and reviewing the course material. The time commitment for use of the case-based tutorial appears to be justified. PMID:19712473

Evaluation of two recommended disinfection methods for cleaning cloths used in food services of southern Brazil.

PubMed

Bartz, Sabrina; Tondo, Eduardo Cesar

2013-01-01

In the State of Rio Grande do Sul (RS), Southern Brazil, a good manufacturing practices regulation was published recommending two disinfection methods for cleaning cloths used in food services. The aim of the present study was to evaluate the efficacy of those methods. Cleaning cloths were sampled without prior notice at food services, on common working days. For the analyses, the cloths were divided in two sub-samples, being one of them microbiologically analyzed. The second sub-sample was further divided in two pieces and submitted to hand washing for two minutes. After that, one piece was boiled in water for 15 min and the other one was soaked in a 200 ppm sodium hypochlorite solution for 15 min. Both pieces of cloth were submitted to microbiological analyses. Cleaning cloths presented total aerobic mean counts of 6.9 ± 6.7 log/cm(2). All cleaning cloths presented coliform contamination, and 40% demonstrated mean counts of 6.2 ± 5.6 log/cm(2). Presumptive S. aureus mean counts of 5.5 ± 4.9 log/cm(2) were found. No statistic correlation was observed among the number of meals served daily in the food services and the microbiological contamination levels. After washing and disinfection, microbiological counts were significantly (p < 0.05) reduced by both methods, achieving an approximately 5 log reduction. The reductions achieved by the sodium hypochlorite soaking method and the boiling method were not significantly different. Thus, it was possible to conclude that both recommended methods were suitable to disinfect cleaning cloths used in food services.

An integrated evaluation of some faecal indicator bacteria (FIB) and chemical markers as potential tools for monitoring sewage contamination in subtropical estuaries.

PubMed

Cabral, Ana Caroline; Stark, Jonathan S; Kolm, Hedda E; Martins, César C

2018-04-01

Sewage input and the relationship between chemical markers (linear alkylbenzenes and coprostanol) and fecal indicator bacteria (FIB, Escherichia coli and enterococci), were evaluated in order to establish thresholds values for chemical markers in suspended particulate matter (SPM) as indicators of sewage contamination in two subtropical estuaries in South Atlantic Brazil. Both chemical markers presented no linear relationship with FIB due to high spatial microbiological variability, however, microbiological water quality was related to coprostanol values when analyzed by logistic regression, indicating that linear models may not be the best representation of the relationship between both classes of indicators. Logistic regression was performed with all data and separately for two sampling seasons, using 800 and 100 MPN 100 mL -1 of E. coli and enterococci, respectively, as the microbiological limits of sewage contamination. Threshold values of coprostanol varied depending on the FIB and season, ranging between 1.00 and 2.23 μg g -1 SPM. The range of threshold values of coprostanol for SPM are relatively higher and more variable than those suggested in literature for sediments (0.10-0.50 μg g -1 ), probably due to higher concentration of coprostanol in SPM than in sediment. Temperature may affect the relationship between microbiological indicators and coprostanol, since the threshold value of coprostanol found here was similar to tropical areas, but lower than those found during winter in temperate areas, reinforcing the idea that threshold values should be calibrated for different climatic conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

A validation of the Danish microbiology database (MiBa) and incidence rate of Actinotignum schaalii (Actinobaculum schaalii) bacteraemia in Denmark.

PubMed

Bank, S; Søby, K M; Kristensen, L H; Voldstedlund, M; Prag, J

2015-12-01

Actinotignum schaalii (former named Actinobaculum schaalii) can cause urinary tract infections (UTIs) and bacteraemia, mainly in the elderly. A. schaalii is difficult to identify with conventional biochemical tests, and it is often overlooked if the urine is only cultured in ambient air. The aim of this study was to validate data from the nationwide Danish microbiology database (MiBa) with data from the laboratory information system (LIS) at the local department of microbiology in Viborg-Herning, and to evaluate the incidence rate of bacteraemia caused by A. schaalii in Denmark by using data from the MiBa. All departments of microbiology in Denmark report data to the MiBa. All microbiological samples with A. schaalii in Denmark were extracted for a period of 5 years from the MiBa and from the local LISs. All data obtained from our local LIS were also found in the MiBa, except for data on real-time PCR, which were not registered, owing to missing ID codes in the MiBa. From 2010 to 2014, there was a significant increase in the incidence rate of blood cultures with A. schaalii, from 1.8 to 6.8 cases per million, which was probably due to coincident implementation of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in routine diagnostics. We found that A. schaalii caused bacteraemia and UTIs mainly in the elderly. In conclusion, the MiBa can be a useful source of nationwide microbiological data in Denmark. Our results suggest that the incidence rate of A. schaalii as a cause of bacteraemia has been underestimated, and that culture of urine in CO2 can improve the detection of A. schaalii. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Frontiers in Microbiology: Envisioning a Curriculum Unit for High School Biology

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

Mark Bloom

Microbiology is undergoing a quiet revolution. Techniques such as polymerase chain reaction, high throughput DNA sequencing, whole genome shotgun sequencing, DNA microarrays, and bioinformatics analyses are greatly aiding our understanding of the estimated one billion species of microbes that inhabit the Earth. Unfortunately, the rapid pace of research in microbiology stands in contrast to the much slower pace of change in educational reform. Biological Sciences Curriculum Study (BSCS) hosted a two-day planning meeting to discuss whether or not a new curriculum unit on microbiology is desirable for the high school audience. Attending the meeting were microbiologists, high school biology teachers,more » and science educators. The consensus of the participants was that an inquiry-based unit dealing with advances in microbiology should be developed for a high school biology audience. Participants established content priorities for the unit, discussed the unit's conceptual flow, brainstormed potential student activities, and discussed the role of educational technology for the unit. As a result of the planning meeting discussions, BSCS staff sought additional funding to develop, disseminate, and evaluate the Frontiers in Microbiology curriculum unit. This unit was intended to be developed as a replacement unit suitable for an introductory biology course. The unit would feature inquiry-based student activities and provide approximately four weeks of instruction. As appropriate, activities would make use of multimedia. The development and production processes would require about two years for completion. Unfortunately, BSCS staff was not able to attract sufficient funding to develop the proposed curriculum unit. Since there were some unexpended funds left over from the planning meeting, BSCS requested and received permission from DOE to use the balance of the funds to prepare background materials about advances in microbiology that would be useful to teachers. These materials were developed and placed on the BSCS Web site (http://www.bscs.org).« less

Comparison of the Microbiological Quality and Safety between Conventional and Organic Vegetables Sold in Malaysia

PubMed Central

Kuan, Chee-Hao; Rukayadi, Yaya; Ahmad, Siti H.; Wan Mohamed Radzi, Che W. J.; Thung, Tze-Young; Premarathne, Jayasekara M. K. J. K.; Chang, Wei-San; Loo, Yuet-Ying; Tan, Chia-Wanq; Ramzi, Othman B.; Mohd Fadzil, Siti N.; Kuan, Chee-Sian; Yeo, Siok-Koon; Nishibuchi, Mitsuaki; Radu, Son

2017-01-01

Given the remarkable increase of public interest in organic food products, it is indeed critical to evaluate the microbiological risk associated with consumption of fresh organic produce. Organic farming practices including the use of animal manures may increase the risk of microbiological contamination as manure can act as a vehicle for transmission of foodborne pathogens. This study aimed to determine and compare the microbiological status between organic and conventional fresh produce at the retail level in Malaysia. A total of 152 organic and conventional vegetables were purchased at retail markets in Malaysia. Samples were analyzed for mesophilic aerobic bacteria, yeasts and molds, and total coliforms using conventional microbiological methods. Combination methods of most probable number-multiplex polymerase chain reaction (MPN-mPCR) were used to detect and quantify foodborne pathogens, including Escherichia coli O157:H7, Shiga toxin-producing E. coli (STEC), Listeria monocytogenes, Salmonella Typhimurium, and Salmonella Enteritidis. Results indicated that most types of organic and conventional vegetables possessed similar microbial count (P > 0.05) of mesophilic aerobic bacteria, yeasts and molds, and total coliforms. E. coli O157:H7 and S. Typhimurium were not detected in any sample analyzed in this study. Among the 152 samples tested, only the conventional lettuce and organic carrot were tested positive for STEC and S. Enteritidis, respectively. L. monocytogenes were more frequently detected in both organic (9.1%) and conventional vegetables (2.7%) as compared to E. coli O157:H7, S. Typhimurium, and S. Enteritidis. Overall, no trend was shown that either organically or conventionally grown vegetables have posed greater microbiological risks. These findings indicated that one particular type of farming practices would not affect the microbiological profiles of fresh produce. Therefore, regardless of farming methods, all vegetables should be subjected to appropriate post-harvest handling practices from farm to fork to ensure the quality and safety of the fresh produce. PMID:28824567

Comparison of the Microbiological Quality and Safety between Conventional and Organic Vegetables Sold in Malaysia.

PubMed

Kuan, Chee-Hao; Rukayadi, Yaya; Ahmad, Siti H; Wan Mohamed Radzi, Che W J; Thung, Tze-Young; Premarathne, Jayasekara M K J K; Chang, Wei-San; Loo, Yuet-Ying; Tan, Chia-Wanq; Ramzi, Othman B; Mohd Fadzil, Siti N; Kuan, Chee-Sian; Yeo, Siok-Koon; Nishibuchi, Mitsuaki; Radu, Son

2017-01-01

Given the remarkable increase of public interest in organic food products, it is indeed critical to evaluate the microbiological risk associated with consumption of fresh organic produce. Organic farming practices including the use of animal manures may increase the risk of microbiological contamination as manure can act as a vehicle for transmission of foodborne pathogens. This study aimed to determine and compare the microbiological status between organic and conventional fresh produce at the retail level in Malaysia. A total of 152 organic and conventional vegetables were purchased at retail markets in Malaysia. Samples were analyzed for mesophilic aerobic bacteria, yeasts and molds, and total coliforms using conventional microbiological methods. Combination methods of most probable number-multiplex polymerase chain reaction (MPN-mPCR) were used to detect and quantify foodborne pathogens, including Escherichia coli O157:H7, Shiga toxin-producing E. coli (STEC), Listeria monocytogenes, Salmonella Typhimurium, and Salmonella Enteritidis. Results indicated that most types of organic and conventional vegetables possessed similar microbial count ( P > 0.05) of mesophilic aerobic bacteria, yeasts and molds, and total coliforms. E. coli O157:H7 and S . Typhimurium were not detected in any sample analyzed in this study. Among the 152 samples tested, only the conventional lettuce and organic carrot were tested positive for STEC and S . Enteritidis, respectively. L. monocytogenes were more frequently detected in both organic (9.1%) and conventional vegetables (2.7%) as compared to E. coli O157:H7, S . Typhimurium, and S . Enteritidis. Overall, no trend was shown that either organically or conventionally grown vegetables have posed greater microbiological risks. These findings indicated that one particular type of farming practices would not affect the microbiological profiles of fresh produce. Therefore, regardless of farming methods, all vegetables should be subjected to appropriate post-harvest handling practices from farm to fork to ensure the quality and safety of the fresh produce.

Comparison of clinical diagnosis and microbiological test results in vaginal infections.

PubMed

Karaca, M; Bayram, A; Kocoglu, M E; Gocmen, A; Eksi, F

2005-01-01

Lower genital tract infections continue to be a problem due to the fact that the clinical diagnosis is usually inadequate, and subsequent care is suboptimal. This study aimed at evaluating the accuracy of clinical diagnosis by comparing it with microbiologic test results, and to determine the causative agents of vaginal infections. Sixty-seven nonpregnant women (18-45 years of age) with the clinical diagnosis of lower genital tract infection were enrolled in the study. Patients were not included if they had a history of vaginal infection during the previous three-month period or intrauterine device. The clinical diagnosis was based on the combinations of symptoms, direct observation of wet mount, homogeneous discharge, vaginal pH > 4.5, and detection of the amine odor after exposure of vaginal secretions to 10% KOH. Vaginal samples were taken with two cotton swabs, one was used for pH determination, and the second was utilized for microbiological tests. Gram staining and cultures with Sabouraud agar and chocolate agar were performed for microbiological diagnosis, and the results were compared. The clinical diagnoses included 26 (38.8%) candidiasis, 18 (26.8%) bacterial vaginosis, three (4.5%) trichomoniasis, and 20 (29.9%) mixed vaginal infections. Of the 26 patients with clinical diagnoses of candidiasis, 12 (46.1%) revealed Candiada albicans, nine (34.6) patients revealed microorganisms other than candida species, and five (19.2%) patients had no growth. Five (27.8%) bacterial vaginosis patients revealed Gardnarella vaginalis and 12 patients (66.6%) did not grow any microorganism. The overall rate of accurate clinical diagnoses confirmed by microbiological test results was 43.2%. Seventeen (43.6) of the 39 microbiological test results correlated with clinical diagnosis, and no growth was observed in 28 (41.8%) cultures. We conclude that the clinical diagnosis of vaginal infection is inadequate and should be confirmed with microbiological testing if the resources are avaliable.

Randomized prospective study comparing vancomycin with teicoplanin in the treatment of infections associated with Hickman catheters.

PubMed Central

Smith, S R; Cheesbrough, J; Spearing, R; Davies, J M

1989-01-01

In 72 episodes of suspected or proven Hickman-catheter-associated infection occurring in 59 patients with various hematological disorders, patients were assigned to treatment with either vancomycin or teicoplanin in a randomized nonblinded prospective study. Of 60 episodes evaluable for response, 28 were treated with vancomycin and 32 were treated with teicoplanin. Sixteen infective episodes were microbiologically documented in the vancomycin group, and twenty-one were microbiologically documented in the teicoplanin group. Microbiologically and clinically documented infections treated with vancomycin had an 80% response rate, compared with a 69% response rate for those treated with teicoplanin (P = 0.316). Adverse events occurred in nine (25%) of the episodes in the vancomycin group, compared with three (8%) in the teicoplanin group (P = 0.044). Teicoplanin may provide an effective alternative to vancomycin in the treatment of Hickman-catheter-associated infection in patients with hematological malignancies. PMID:2529814

Randomized prospective study comparing vancomycin with teicoplanin in the treatment of infections associated with Hickman catheters.

PubMed

Smith, S R; Cheesbrough, J; Spearing, R; Davies, J M

1989-08-01

In 72 episodes of suspected or proven Hickman-catheter-associated infection occurring in 59 patients with various hematological disorders, patients were assigned to treatment with either vancomycin or teicoplanin in a randomized nonblinded prospective study. Of 60 episodes evaluable for response, 28 were treated with vancomycin and 32 were treated with teicoplanin. Sixteen infective episodes were microbiologically documented in the vancomycin group, and twenty-one were microbiologically documented in the teicoplanin group. Microbiologically and clinically documented infections treated with vancomycin had an 80% response rate, compared with a 69% response rate for those treated with teicoplanin (P = 0.316). Adverse events occurred in nine (25%) of the episodes in the vancomycin group, compared with three (8%) in the teicoplanin group (P = 0.044). Teicoplanin may provide an effective alternative to vancomycin in the treatment of Hickman-catheter-associated infection in patients with hematological malignancies.

Measures of Searcher Performance: A Psychometric Evaluation.

ERIC Educational Resources Information Center

Wildemuth, Barbara M.; And Others

1993-01-01

Describes a study of medical students that was conducted to evaluate measures of performance on factual searches of INQUIRER, a full-text database in microbiology. Measures relating to recall, precision, search term overlap, and efficiency are discussed; reliability and construct validity are considered; and implications for future research are…

Evaluation of a Pour-Through Water Treatment Device for Use as Microbiological Purifier

EPA Science Inventory

The United States Environmental Protection Agency (EPA) Office of Research and Development has evaluated the performance of a Point-of-Use (POU) pour-through device designed for use in India, developing and emerging market (D&E) countries, and under emergency situations in the Un...

ENVIRONMENTAL RESEARCH BRIEF: LONG-TERM PERFORMANCE OF PERMEABLE REACTIVE BARRIERS USING ZERO-VALENT IRON: AN EVALUATION AT TWO SITES

EPA Science Inventory

Geochemical and microbiological factors that control long-term performance of subsurface permeable reactive barriers were evaluated at the Elizabeth City, NC and the Denver Federal Center, CO sites. These groundwater treatment systems use zero-valent iron filings to intercept an...

Management of Meloidogyne incognita on tomato with endophytic bacteria and fresh residue of Wasabia japonica.

PubMed

Li, G J; Dong, Q E; Ma, L; Huang, Y; Zhu, M L; Ji, Y P; Wang, Q H; Mo, M H; Zhang, K Q

2014-10-01

To characterize the nematicidal endophytic bacteria (NEB) of Wasabia japonica (wasabi) and evaluated the control efficacies of promising NEB as well as fresh wasabi residue (FWR) against Meloidogyne incognita on tomato. By in vitro bioassay, 53 NEB strains showing nematicidal efficacies of >50% against J2 of M. incognita were isolated from wasabi. Basing on 16S rRNA gene sequences, these NEB were identified into 18 species of 11 genera. In greenhouse, incorporation of selected NEB culture or FWR into potted soil significantly reduced infection of M. incognita on tomato. Treating tomatoes with either FWR or NEB of Raoultella terrigena RN16 and Pseudomonas reinekei SN21 in the field yielded excellent control efficacies against M. incognita, especially the combinations of FWR with either R. terrigena RN16 or Ps. reinekei SN21 at doses of 50 g plus 100 ml per plant or more. The results established that R. terrigena RN16 and Ps. reinekei SN21 applied separately or combined with FWR have the potential to provide bioprotection agents against M. incognita. This study provides novel way for disease management using combination of endophyte and host residue. © 2014 The Society for Applied Microbiology.

Biocontrol of the Potato Blackleg and Soft Rot Diseases Caused by Dickeya dianthicola.

PubMed

Raoul des Essarts, Yannick; Cigna, Jérémy; Quêtu-Laurent, Angélique; Caron, Aline; Munier, Euphrasie; Beury-Cirou, Amélie; Hélias, Valérie; Faure, Denis

2016-01-01

Development of protection tools targeting Dickeya species is an important issue in the potato production. Here, we present the identification and the characterization of novel biocontrol agents. Successive screenings of 10,000 bacterial isolates led us to retain 58 strains that exhibited growth inhibition properties against several Dickeya sp. and/or Pectobacterium sp. pathogens. Most of them belonged to the Pseudomonas and Bacillus genera. In vitro assays revealed a fitness decrease of the tested Dickeya sp. and Pectobacterium sp. pathogens in the presence of the biocontrol agents. In addition, four independent greenhouse assays performed to evaluate the biocontrol bacteria effect on potato plants artificially contaminated with Dickeya dianthicola revealed that a mix of three biocontrol agents, namely, Pseudomonas putida PA14H7 and Pseudomonas fluorescens PA3G8 and PA4C2, repeatedly decreased the severity of blackleg symptoms as well as the transmission of D. dianthicola to the tuber progeny. This work highlights the use of a combination of biocontrol strains as a potential strategy to limit the soft rot and blackleg diseases caused by D. dianthicola on potato plants and tubers. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

In vitro evaluation of microbial contamination of orthodontic brackets as received from the manufacturer using microbiological and molecular tests.

PubMed

Dos Santos Gerzson, Darlene R; Simon, Daniel; Dos Anjos, Aline Lima; Freitas, Maria Perpétua Mota

2015-11-01

To test the null hypothesis that orthodontic brackets as supplied by manufacturers do not have microbial contamination. The sample comprised 140 brackets of four different commercially available brands, used directly from the manufacturer's packaging, divided into 14 groups (n  =  10 brackets each). Of the 140 pieces, 60 were full cases and 80 were replacement brackets. Materials were tested to detect bacterial growth, analyze types of bacteria present (biochemical test), and identify bacteria (molecular test with polymerase chain reaction [PCR]). In two of 12 groups the brackets showed microbial contamination: group 1, Morelli full case brackets, and group 12, Abzil-3M Unitek replacement brackets. Staphylococcus aureus and Staphylococcus epidermidis were the bacteria identified in groups 1 and 12, respectively (suggested by the biochemical test and confirmed by PCR). Brackets of two brands (Morelli and Abzil-3M Unitek) were found to be contaminated by bacteria in the original packages supplied by the manufacturers, which suggests a risk for patient contamination. These data suggest that the manufacturers of these materials should improve the quality control of the packaging used, including sterilization, for the security of patient health.

Topical application of probiotics in skin: adhesion, antimicrobial and antibiofilm in vitro assays.

PubMed

Lopes, E G; Moreira, D A; Gullón, P; Gullón, B; Cardelle-Cobas, A; Tavaria, F K

2017-02-01

When skin dysbiosis occurs as a result of skin disorders, probiotics can act as modulators, restoring microbial balance. Several properties of selected probiotics were evaluated so that their topical application could be considered. Adhesion, antimicrobial, quorum sensing and antibiofilm assays were carried out with several probiotic strains and tested against selected skin pathogens. All tested strains displayed significant adhesion to keratin. All lactobacilli with the exception of Lactobacillus delbrueckii, showed antimicrobial activity against skin pathogens, mainly due to organic acid production. Most of them also prevented biofilm formation, but only Propioniferax innocua was able to break down mature biofilms. This study demonstrates that although all tested probiotics adhered to human keratin, they showed limited ability to prevent adhesion of some potential skin pathogens. Most of the tested probiotics successfully prevented biofilm formation, suggesting that they may be successfully used in the future as a complement to conventional therapies in the treatment of a range of skin disorders. The topically used probiotics may be a natural, targeted treatment approach to several skin disorders and a complement to conventional therapies which present many undesirable side effects. © 2016 The Society for Applied Microbiology.

Novel Heteroaryl Selenocyanates and Diselenides as Potent Antileishmanial Agents.

PubMed

Baquedano, Ylenia; Alcolea, Verónica; Toro, Miguel Ángel; Gutiérrez, Killian Jesús; Nguewa, Paul; Font, María; Moreno, Esther; Espuelas, Socorro; Jiménez-Ruiz, Antonio; Palop, Juan Antonio; Plano, Daniel; Sanmartín, Carmen

2016-06-01

A series of new selenocyanates and diselenides bearing interesting bioactive scaffolds (quinoline, quinoxaline, acridine, chromene, furane, isosazole, etc.) was synthesized, and their in vitro leishmanicidal activities against Leishmania infantum amastigotes along with their cytotoxicities in human THP-1 cells were determined. Interestingly, most tested compounds were active in the low micromolar range and led us to identify four lead compounds (1h, 2d, 2e, and 2f) with 50% effective dose (ED50) values ranging from 0.45 to 1.27 μM and selectivity indexes of >25 for all of them, much higher than those observed for the reference drugs. These active derivatives were evaluated against infected macrophages, and in order to gain preliminary knowledge about their possible mechanism of action, the inhibition of trypanothione reductase (TryR) was measured. Among these novel structures, compounds 1h (3,5-dimethyl-4-isoxazolyl selenocyanate) and 2d [3,3'-(diselenodiyldimethanediyl)bis(2-bromothiophene)] exhibited good association between TryR inhibitory activity and antileishmanial potency, pointing to 1h, for its excellent theoretical ADME (absorption, distribution, metabolism, and excretion) properties, as the most promising lead molecule for leishmancidal drug design. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Teicoplanin-loaded borate bioactive glass implants for treating chronic bone infection in a rabbit tibia osteomyelitis model.

PubMed

Zhang, Xin; Jia, Weitao; Gu, Yifei; Xiao, Wei; Liu, Xin; Wang, Deping; Zhang, Changqing; Huang, Wenhai; Rahaman, Mohamed N; Day, Delbert E; Zhou, Nai

2010-08-01

The treatment of chronic osteomyelitis (bone infection) remains a clinical challenge. In this work, pellets composed of a chitosan-bonded mixture of borate bioactive glass particles (<50microm) and teicoplanin powder (antibiotic), were evaluated in vitro and in vivo for treating chronic osteomyelitis induced by methicillin-resistant Staphylococcus aureus (MRSA) in a rabbit model. When immersed in phosphate-buffered saline, the pellets showed sustained release of teicoplanin over 20-30 days, while the bioactive glass converted to hydroxyapatite (HA) within 7 days, eventually forming a porous HA structure. Implantation of the teicoplanin-loaded pellets in a rabbit tibia osteomyelitis model resulted in the detection of teicoplanin in the blood for about 9 days. The implants converted to a bone-like HA graft, and supported the ingrowth of new bone into the tibia defects within 12 weeks of implantation. Microbiological, histological and scanning electron microscopy techniques showed that the implants provided a cure for the bone infection. The results indicate that the teicoplanin-loaded borate bioactive glass implant, combining sustained drug release with the ability to support new bone ingrowth, could provide a method for treating chronic osteomyelitis. Copyright 2010 Elsevier Ltd. All rights reserved.

Respiratory and Allergic Health Effects of Dampness, Mold, and Dampness-Related Agents: A Review of the Epidemiologic Evidence

PubMed Central

Mendell, Mark J.; Mirer, Anna G.; Cheung, Kerry; Tong, My; Douwes, Jeroen

2011-01-01

Objectives Many studies have shown consistent associations between evident indoor dampness or mold and respiratory or allergic health effects, but causal links remain unclear. Findings on measured microbiologic factors have received little review. We conducted an updated, comprehensive review on these topics. Data sources We reviewed eligible peer-reviewed epidemiologic studies or quantitative meta-analyses, up to late 2009, on dampness, mold, or other microbiologic agents and respiratory or allergic effects. Data extraction We evaluated evidence for causation or association between qualitative/subjective assessments of dampness or mold (considered together) and specific health outcomes. We separately considered evidence for associations between specific quantitative measurements of microbiologic factors and each health outcome. Data synthesis Evidence from epidemiologic studies and meta-analyses showed indoor dampness or mold to be associated consistently with increased asthma development and exacerbation, current and ever diagnosis of asthma, dyspnea, wheeze, cough, respiratory infections, bronchitis, allergic rhinitis, eczema, and upper respiratory tract symptoms. Associations were found in allergic and nonallergic individuals. Evidence strongly suggested causation of asthma exacerbation in children. Suggestive evidence was available for only a few specific measured microbiologic factors and was in part equivocal, suggesting both adverse and protective associations with health. Conclusions Evident dampness or mold had consistent positive associations with multiple allergic and respiratory effects. Measured microbiologic agents in dust had limited suggestive associations, including both positive and negative associations for some agents. Thus, prevention and remediation of indoor dampness and mold are likely to reduce health risks, but current evidence does not support measuring specific indoor microbiologic factors to guide health-protective actions. PMID:21269928

Evaluation of hygiene practices and microbiological quality of cooked meat products during slicing and handling at retail.

PubMed

Pérez-Rodríguez, F; Castro, R; Posada-Izquierdo, G D; Valero, A; Carrasco, E; García-Gimeno, R M; Zurera, G

2010-10-01

Cooked meat ready-to-eat products are recognized to be contaminated during slicing which, in the last years, has been associated with several outbreaks. This work aimed to find out possible relation between the hygiene practice taking place at retail point during slicing of cooked meat products in small and medium-sized establishments (SMEs) and large-sized establishments (LEs) and the microbiological quality of sliced cooked meat products. For that, a checklist was drawn up and filled in based on scoring handling practice during slicing in different establishments in Cordoba (Southern Spain). In addition, sliced cooked meats were analyzed for different microbiological indicators and investigated for the presence of Listeria spp. and Listeria monocytogenes. Results indicated that SMEs showed a more deficient handling practices compared to LEs. In spite of these differences, microbiological counts indicated similar microbiological quality in cooked meat samples for both types of establishments. On the other hand, Listeria monocytogenes and Listeria inocua were isolated from 7.35% (5/68) and 8.82% (6/68) of analyzed samples, respectively. Positive samples for Listeria spp. were found in establishments which showed acceptable hygiene levels, though contamination could be associated to the lack of exclusiveness of slicers at retail points. Moreover, Listeria spp presence could not be statistically linked to any microbiological parameters; however, it was observed that seasonality influenced significantly (P<0.05) L. monocytogenes presence, being all samples found during warm season (5/5). As a conclusion, results suggested that more effort should be made to adequately educate handlers in food hygiene practices, focused specially on SMEs. Copyright (c) 2010 Elsevier B.V. All rights reserved.

ϕX174 Procapsid Assembly: Effects of an Inhibitory External Scaffolding Protein and Resistant Coat Proteins In Vitro.

PubMed

Cherwa, James E; Tyson, Joshua; Bedwell, Gregory J; Brooke, Dewey; Edwards, Ashton G; Dokland, Terje; Prevelige, Peter E; Fane, Bentley A

2017-01-01

During ϕX174 morphogenesis, 240 copies of the external scaffolding protein D organize 12 pentameric assembly intermediates into procapsids, a reaction reconstituted in vitro In previous studies, ϕX174 strains resistant to exogenously expressed dominant lethal D genes were experimentally evolved. Resistance was achieved by the stepwise acquisition of coat protein mutations. Once resistance was established, a stimulatory D protein mutation that greatly increased strain fitness arose. In this study, in vitro biophysical and biochemical methods were utilized to elucidate the mechanistic details and evolutionary trade-offs created by the resistance mutations. The kinetics of procapsid formation was analyzed in vitro using wild-type, inhibitory, and experimentally evolved coat and scaffolding proteins. Our data suggest that viral fitness is correlated with in vitro assembly kinetics and demonstrate that in vivo experimental evolution can be analyzed within an in vitro biophysical context. Experimental evolution is an extremely valuable tool. Comparisons between ancestral and evolved genotypes suggest hypotheses regarding adaptive mechanisms. However, it is not always possible to rigorously test these hypotheses in vivo We applied in vitro biophysical and biochemical methods to elucidate the mechanistic details that allowed an experimentally evolved virus to become resistant to an antiviral protein and then evolve a productive use for that protein. Moreover, our results indicate that the respective roles of scaffolding and coat proteins may have been redistributed during the evolution of a two-scaffolding-protein system. In one-scaffolding-protein virus assembly systems, coat proteins promiscuously interact to form heterogeneous aberrant structures in the absence of scaffolding proteins. Thus, the scaffolding protein controls fidelity. During ϕX174 assembly, the external scaffolding protein acts like a coat protein, self-associating into large aberrant spherical structures in the absence of coat protein, whereas the coat protein appears to control fidelity. Copyright © 2016 American Society for Microbiology.

Field assessment of bacterial communities and total trihalomethanes: Implications for drinking water networks.

PubMed

Montoya-Pachongo, Carolina; Douterelo, Isabel; Noakes, Catherine; Camargo-Valero, Miller Alonso; Sleigh, Andrew; Escobar-Rivera, Juan-Carlos; Torres-Lozada, Patricia

2018-03-01

Operation and maintenance (O&M) of drinking water distribution networks (DWDNs) in tropical countries simultaneously face the control of acute and chronic risks due to the presence of microorganisms and disinfection by-products, respectively. In this study, results from a detailed field characterization of microbiological, chemical and infrastructural parameters of a tropical-climate DWDN are presented. Water physicochemical parameters and the characteristics of the network were assessed to evaluate the relationship between abiotic and microbiological factors and their association with the presence of total trihalomethanes (TTHMs). Illumina sequencing of the bacterial 16s rRNA gene revealed significant differences in the composition of biofilm and planktonic communities. The highly diverse biofilm communities showed the presence of methylotrophic bacteria, which suggest the presence of methyl radicals such as THMs within this habitat. Microbiological parameters correlated with water age, pH, temperature and free residual chlorine. The results from this study are necessary to increase the awareness of O&M practices in DWDNs required to reduce biofilm formation and maintain appropriate microbiological and chemical water quality, in relation to biofilm detachment and DBP formation. Copyright © 2017 Elsevier B.V. All rights reserved.

Chemical, Physicochemical, Nutritional, Microbiological, Sensory and Rehydration Characteristics of Instant Whole Beans (Phaseolus vulgaris).

PubMed

Ulloa, José Armando; Ibarra-Zavala, Silvia Jazmin; Ramírez-Salas, Silvia Patricia; Rosas-Ulloa, Petra; Ramírez-Ramírez, José Carmen; Ulloa-Rangel, Blanca Estela

2015-03-01

Instant whole beans obtained by drying at 25 °C were evaluated for their chemical, physicochemical, nutritional, microbiological, sensory and rehydration characteristics. The proximal composition of instant whole beans was typical of this kind of food, whereas a w and L* , a* and b* values were 0.639, 98.55, -0.28 and -1.52, respectively. In instant whole beans, 75% of the essential amino acids had a value greater or equal to the reference standard for adult humans; the protein quality in terms of chemical score was 95%. Microbiological counts of aerobic mesophilic bacteria, moulds, yeasts and total coliforms of rehydrated instant whole beans were <10 CFU/g, whereas the scores for colour, flavour, texture and overall acceptability were 7.22, 7.68, 7.24 and 7.34, respectively, on a 1-9 hedonic scale. The logarithmic and Pilosof models showed close fits (R 2 >0.99) to the experimental data for drying of cooked beans and rehydration of instant whole beans, respectively. In the light of the chemical, physicochemical, nutritional, microbiological, sensory and rehydration characteristics of instant whole beans found in this study, drying at 25 °C is recommended for the production of such food.

Can Particulate Air Sampling Predict Microbial Load in Operating Theatres for Arthroplasty?

PubMed Central

Cristina, Maria Luisa; Spagnolo, Anna Maria; Sartini, Marina; Panatto, Donatella; Gasparini, Roberto; Orlando, Paolo; Ottria, Gianluca; Perdelli, Fernanda

2012-01-01

Several studies have proposed that the microbiological quality of the air in operating theatres be indirectly evaluated by means of particle counting, a technique derived from industrial clean-room technology standards, using airborne particle concentration as an index of microbial contamination. However, the relationship between particle counting and microbiological sampling has rarely been evaluated and demonstrated in operating theatres. The aim of the present study was to determine whether particle counting could predict microbiological contamination of the air in an operating theatre during 95 surgical arthroplasty procedures. This investigation was carried out over a period of three months in 2010 in an orthopedic operating theatre devoted exclusively to prosthetic surgery. During each procedure, the bacterial contamination of the air was determined by means of active sampling; at the same time, airborne particulate contamination was assessed throughout the entire procedure. On considering the total number of surgical operations, the mean value of the total bacterial load in the center of the operating theatre proved to be 35 CFU/m3; the mean particle count was 4,194,569 no./m3 for particles of diameter ≥0.5 µm and 13,519 no./m3 for particles of diameter ≥5 µm. No significant differences emerged between the median values of the airborne microbial load recorded during the two types of procedure monitored. Particulates with a diameter of ≥0.5 µm were detected in statistically higher concentrations (p<0.001) during knee-replacement procedures. By contrast, particulates with a diameter of ≥5 µm displayed a statistically higher concentration during hip-replacement procedures (p<0.05). The results did not reveal any statistically significant correlation between microbial loads and particle counts for either of the particle diameters considered (≥0.5 µm and ≥5 µm). Consequently, microbiological monitoring remains the most suitable method of evaluating the quality of air in operating theatres. PMID:23285189

Can particulate air sampling predict microbial load in operating theatres for arthroplasty?

PubMed

Cristina, Maria Luisa; Spagnolo, Anna Maria; Sartini, Marina; Panatto, Donatella; Gasparini, Roberto; Orlando, Paolo; Ottria, Gianluca; Perdelli, Fernanda

2012-01-01

Several studies have proposed that the microbiological quality of the air in operating theatres be indirectly evaluated by means of particle counting, a technique derived from industrial clean-room technology standards, using airborne particle concentration as an index of microbial contamination. However, the relationship between particle counting and microbiological sampling has rarely been evaluated and demonstrated in operating theatres. The aim of the present study was to determine whether particle counting could predict microbiological contamination of the air in an operating theatre during 95 surgical arthroplasty procedures. This investigation was carried out over a period of three months in 2010 in an orthopedic operating theatre devoted exclusively to prosthetic surgery. During each procedure, the bacterial contamination of the air was determined by means of active sampling; at the same time, airborne particulate contamination was assessed throughout the entire procedure. On considering the total number of surgical operations, the mean value of the total bacterial load in the center of the operating theatre proved to be 35 CFU/m(3); the mean particle count was 4,194,569 no./m(3) for particles of diameter ≥0.5 µm and 13,519 no./m(3) for particles of diameter ≥5 µm. No significant differences emerged between the median values of the airborne microbial load recorded during the two types of procedure monitored. Particulates with a diameter of ≥0.5 µm were detected in statistically higher concentrations (p<0.001) during knee-replacement procedures. By contrast, particulates with a diameter of ≥5 µm displayed a statistically higher concentration during hip-replacement procedures (p<0.05). The results did not reveal any statistically significant correlation between microbial loads and particle counts for either of the particle diameters considered (≥0.5 µm and ≥5 µm). Consequently, microbiological monitoring remains the most suitable method of evaluating the quality of air in operating theatres.

A risk modelling approach for setting microbiological limits using enterococci as indicator for growth potential of Salmonella in pork.

PubMed

Bollerslev, Anne Mette; Nauta, Maarten; Hansen, Tina Beck; Aabo, Søren

2017-01-02

Microbiological limits are widely used in food processing as an aid to reduce the exposure to hazardous microorganisms for the consumers. However, in pork, the prevalence and concentrations of Salmonella are generally low and microbiological limits are not considered an efficient tool to support hygiene interventions. The objective of the present study was to develop an approach which could make it possible to define potential risk-based microbiological limits for an indicator, enterococci, in order to evaluate the risk from potential growth of Salmonella. A positive correlation between the concentration of enterococci and the prevalence and concentration of Salmonella was shown for 6640 pork samples taken at Danish cutting plants and retail butchers. The samples were collected in five different studies in 2001, 2002, 2010, 2011 and 2013. The observations that both Salmonella and enterococci are carried in the intestinal tract, contaminate pork by the same mechanisms and share similar growth characteristics (lag phase and maximum specific growth rate) at temperatures around 5-10°C, suggest a potential of enterococci to be used as an indicator of potential growth of Salmonella in pork. Elevated temperatures during processing will lead to growth of both enterococci and, if present, also Salmonella. By combining the correlation between enterococci and Salmonella with risk modelling, it is possible to predict the risk of salmonellosis based on the level of enterococci. The risk model used for this purpose includes the dose-response relationship for Salmonella and a reduction factor to account for preparation of the fresh pork. By use of the risk model, it was estimated that the majority of salmonellosis cases, caused by the consumption of pork in Denmark, is caused by the small fraction of pork products that has enterococci concentrations above 5logCFU/g. This illustrates that our approach can be used to evaluate the potential effect of different microbiological limits and therefore, the perspective of this novel approach is that it can be used for definition of a risk-based microbiological limit for enterococci. The limit for enterococci can then be used for development of a process hygiene criterion in cutting plants and retail butcher shops, with the purpose of reducing the risk of Salmonella for the consumer. Copyright © 2016 Elsevier B.V. All rights reserved.

A phasin with extra talents: a polyhydroxyalkanoate granule-associated protein has chaperone activity.

PubMed

Mezzina, Mariela P; Wetzler, Diana E; de Almeida, Alejandra; Dinjaski, Nina; Prieto, M Auxiliadora; Pettinari, Maria Julia

2015-05-01

Phasins are proteins associated to intracellular polyhydroxyalkanoate granules that affect polymer accumulation and the number and size of the granules. Previous work demonstrated that a phasin from Azotobacter sp FA-8 (PhaPAz ) had an unexpected growth-promoting and stress-protecting effect in Escherichia coli, suggesting it could have chaperone-like activities. In this work, in vitro and in vivo experiments were performed in order to investigate this possibility. PhaPAz was shown to prevent in vitro thermal aggregation of the model protein citrate synthase and to facilitate the refolding process of this enzyme after chemical denaturation. Microscopy techniques were used to analyse the subcellular localization of PhaPAz in E. coli strains and to study the role of PhaPAz in in vivo protein folding and aggregation. PhaPAz was shown to colocalize with inclusion bodies of PD, a protein that aggregates when overexpressed. A reduction in the number of inclusion bodies of PD was observed when it was coexpressed with PhaPAz or with the known chaperone GroELS. These results demonstrate that PhaPAz has chaperone-like functions both in vitro and in vivo in E. coli recombinants, and suggests that phasins could have a general protective role in natural polyhydroxyalkanoate producers. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

In vitro interaction of actinomycetes isolates with Aspergillus flavus: impact on aflatoxins B1 and B2 production.

PubMed

Verheecke, C; Liboz, T; Darriet, M; Sabaou, N; Mathieu, F

2014-06-01

This work aimed to study the interaction between Actinomycetal isolates and Aspergillus flavus to promote mutual antagonism in contact. Thirty-seven soilborn Streptomyces spp. isolates were chosen as potential candidates. After a 10-day in vitro co-incubation period, 27 isolates respond to the criteria, that is, mutual antagonism in contact. Further aflatoxins B1 and B2 analysis revealed that those 27 isolates reduced aflatoxin B1 residual concentration from 38·6 to 4·4%, depending on the isolate. We selected 12 isolates and tested their capacity to reduce AFB1 in pure culture to start identifying the mechanisms involved in its reduction. AFB1 was reduced by eight isolates. The remaining AFB1 concentration varied between 82·2 and 15·6%. These findings led us to suggest that these eight isolates could be used as biocontrol agents against AFB1 and B2 with low risk of impacting the natural microbial equilibrium. Interaction between Aspergillus flavus and Actinomycetes isolates was conducted in vitro. Actinomycetes isolates having a mutual antagonism in contact with A. flavus were chosen for further aflatoxins production study. This is a new approach based to develop biocontrol against aflatoxins accumulation in maize while respecting natural microbial equilibrium. © 2014 The Society for Applied Microbiology.

Treatment of in vitro enterohemorrhagic Escherichia coli infection using phage and probiotics.

PubMed

Dini, C; Bolla, P A; de Urraza, P J

2016-07-01

To assay the combination of phage and probiotics against EHEC in vitro on infected Hep-2 cells. Phage and probiotics treatments on EHEC O157:H7-infected Hep-2 cells were assayed individually or combined. The effect of freeze-drying on phage and probiotic antimicrobial activity was also studied. While treatment with phage alone increased cell detachment caused by EHEC infection, the treatments with MM alone or in combination with phage proved to effectively diminish cell damage caused by EHEC infection. Combined treatment showed a decrease in apoptotic cell count of 57·3% and a reduction in EHEC adhesion to cell monolayer of 1·2 log CFU. The simultaneous use of phage and probiotics showed no antagonistic effect, and freeze-drying did not affect their antipathogenic activity. The combination of phage and probiotics has great potential for reducing the number of pathogens adhered to epithelial cells during EHEC O157:H7 infection and attenuating the cytotoxic effect derived from it. Further in vivo assays are needed for assessing the actual effectiveness of the treatment. This study presents a freeze-dried formulation of phage and probiotics capable of controlling EHEC infections and reducing epithelial cell damage in vitro. © 2016 The Society for Applied Microbiology.

Pinocembrin, a novel histidine decarboxylase inhibitor with anti-allergic potential in in vitro.

PubMed

Hanieh, Hamza; Hairul Islam, Villianur Ibrahim; Saravanan, Subramanian; Chellappandian, Muthiah; Ragul, Kessavane; Durga, Arumugam; Venugopal, Kaliyamoorthy; Senthilkumar, Venugopal; Senthilkumar, Palanisamy; Thirugnanasambantham, Krishnaraj

2017-11-05

Pinocembrin (5, 7- dihydroxy flavanone) is the most abundant chiral flavonoid found in propolis, exhibiting antioxidant, antimicrobial and anti-inflammatory properties. However, the effect of Pinocembrin on allergic response is unexplored. Thus, current study aimed at investigating the effects of Pinocembrin on IgE-mediated allergic response in vitro. A special emphasis was directed toward histidine decarboxylase (HDC) and other pro-allergic and pro-inflammatory mediators. Preliminary studies, using a microbiological model of Klebsiella pneumoniae, provided first evidences that suggest Pinocembrin as a potential thermal stable inhibitor for HDC. Applying docking analysis revealed possible interaction between Pinocembrin and mammalian HDC. In vitro studies validated the predicted interaction and showed that Pinocembrin inhibits HDC activity and histamine in IgE-sensitized RBL-2H3 in response to dinitrophenol (DNP)-bovine serum albumin (BSA) stimulation. In addition, Pinocembrin mitigated the damage in the mitochondrial membrane, formation of cytoplasmic granules and degranulation as indicated by lower β-hexoseaminidase level. Interestingly, it reduced range of pro-inflammatory mediators in the IgE-mediated allergic response including tumor necrosis factor (TNF)-α, interleukin (IL)-6, nitric oxide (NO), inducible NO synthase (iNOS), phosphorylation of inhibitory kappa B (IкB)-α, prostaglandin (PGE)-2 and cyclooxygenase (COX)-2. In conclusion, current study suggests Pinocembrin as a potential HDC inhibitor, and provides the first evidences it is in vitro anti-allergic properties, suggesting Pinocembrin as a new candidate for natural anti-allergic drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

Endogenous Cryptococcus neoformans endophthalmitis with subretinal abscess in a HIV-infected man.

PubMed

Joseph, Joveeta; Sharma, Savitri; Narayanan, Raja

2018-07-01

To report a rare case of Cryptococcus neoformans endogenous endophthalmitis with subretinal abscess in a 36-year-old HIV-positive man, referred with progressive blurred vision in his right eye for the last 6 months. Vitreous biopsy followed by intravitreal ganciclovir did not result in significant improvement. Microbiology revealed the presence of C. neoformans, and intravitreal amphotericin B was then administered. The patient was treated aggressively with systemic and intravitreal antifungals but had a poor visual and anatomical outcome. A high degree of clinical suspicion combined with microbiological evaluation helped to arrive at an appropriate diagnosis.

Sampling methods for microbiological analysis of red meat and poultry carcasses.

PubMed

Capita, Rosa; Prieto, Miguel; Alonso-Calleja, Carlos

2004-06-01

Microbiological analysis of carcasses at slaughterhouses is required in the European Union for evaluating the hygienic performance of carcass production processes as required for effective hazard analysis critical control point implementation. The European Union microbial performance standards refer exclusively to the excision method, even though swabbing using the wet/dry technique is also permitted when correlation between both destructive and nondestructive methods can be established. For practical and economic reasons, the swab technique is the most extensively used carcass surface-sampling method. The main characteristics, advantages, and limitations of the common excision and swabbing methods are described here.

Microbial identification system for Space Station Freedom

NASA Technical Reports Server (NTRS)

Brown, Harlan D.; Scarlett, Janie B.; Skweres, Joyce A.; Fortune, Russell L.; Staples, John L.; Pierson, Duane L.

1989-01-01

The Environmental Health System (EHS) and Health Maintenance Facility (HMF) on Space Station Freedom will require a comprehensive microbiology capability. This requirement entails the development of an automated system to perform microbial identifications on isolates from a variety of environmental and clinical sources and, when required, to perform antimicrobial sensitivity testing. The unit currently undergoing development and testing is the Automated Microbiology System II (AMS II) built by Vitek Systems, Inc. The AMS II has successfully completed 12 months of laboratory testing and evaluation for compatibility with microgravity operation. The AMS II is a promising technology for use on Space Station Freedom.

Interactive tele-education applied to a distant clinical microbiology specialization university course.

PubMed

Andreazzi, Denise B; Rossi, Flávia; Wen, Chao L

2011-09-01

The microbiology laboratory provides a strategic support for infectious disease diagnosis and also alerts the medical community about bacterial resistance to antibiotics. The microbiologists' training is a challenge in Brazil, a country with an extensive territory, a diverse population, and disparity of resource allocation. The aim of this study was to implement an interactive tele-educational course in clinical microbiology to reach distant laboratory workers and to improve their professional skills. The course scientific content was defined according to competences associated, distributed in 560 h, with laboratory practices (knowledge matrix-contextual education). The 11-module course structure comprised 70% distance learning, 22% on campus (integrated modules), and 8% monographs. The group included 7 physicians and 21 microbiologists from 20 different Brazilian cities. The time flexibility and location were the two main reasons for student participation, thus decreasing absences to the workplace, different from the traditional teaching methodologies. The group performance was measured by monthly evaluations, and 1 year postcourse, the researcher visited their workplace. There was significant improvement in microbiological practices performed before compared with after group participation. Therefore, 76.9% of laboratory practices were modified because of the knowledge acquired in the course. Students showed behavioral changes in relation to performance in infection control as well as on the dissemination of their knowledge. This specialization course using distance education did not compromise the quality. This educational methodology represents an alternative to teach clinical microbiology to laboratory workers from remote hospitals, as a nationwide continuing educational strategy.

Evaluation of ferrihydrite as amendment to restore an arsenic-polluted mine soil.

PubMed

Abad-Valle, P; Álvarez-Ayuso, E; Murciego, A

2015-05-01

The effectiveness of ferrihydrite as amendment to restore the soil habitat functioning of a soil polluted with As by mining activities was evaluated. Its influence on As mobility and phytoavailability was also assessed. Soil treated with increasing amendment doses (0, 1, 2, and 5 %) were analyzed for soil microbiological parameters such as basal soil respiration and dehydrogenase, β-glucosidase, urease, acid and alkaline phosphatase, and arylsulfatase activities. Batch leaching tests and plant growth experiments using ryegrass and alfalfa plants were performed. The treatment with ferrihydrite was effective to reduce As mobility and plant As uptake, translocation, and accumulation. Likewise, the soil microbiological status was generally improved as derived from basal soil respiration and dehydrogenase and acid and alkaline phosphatase activities, which showed increases up to 85, 45, 11, and 47 %, respectively, at a ferrihydrite addition rate of 5 %.

[Physicochemical and microbiological evaluation of 3 commercial guava jams (Psidium guajava L.)].

PubMed

López, R; Ramírez, A O; Graziani de Fariñas, L

2000-09-01

Four different production batches were taken from each brand. Samples were purchased from retail markets in Maracay, Cagua and Turmero. (Venezuela). The average physical and chemical values were: vacuum = 38.81 cm Hg; pH = 3.28; titrable acidity (%citric acid) = 0.59%; degree Brix = 67.24; reducing sugars = 55.28%; total sugars = 62.28, and the color parameters a = +14.44, b = +8.77 and L = 17.09. Molds, yeast and aerobic plate counts were lower than 10 UFC/g; it reveals an excellent microbiological quality of the product. The studied jams degree Brix and acidity fulfil COVENIN (1) requirements for jam products, but not pH range. In agreement with variance analysis, there were highly significance differences between the samples and among the shares of each sample for all physical and chemical properties evaluated.

Flow cytometry as a method for the evaluation of raw material, product and process in the dairy industry.

PubMed

Ruszczyńska, A; Szteyn, J; Wiszniewska-Laszczych, A

2007-01-01

Producing dairy products which are safe for consumers requires the constant monitoring of the microbiological quality of raw material, the production process itself and the end product. Traditional methods, still a "gold standard", require a specialized laboratory working on recognized and validated methods. Obtaining results is time- and labor-consuming and do not allow rapid evaluation. Hence, there is a need for a rapid, precise method enabling the real-time monitoring of microbiological quality, and flow cytometry serves this function well. It is based on labeling cells suspended in a solution with fluorescent dyes and pumping them into a measurement zone where they are exposed to a precisely focused laser beam. This paper is aimed at presenting the possibilities of applying flow cytometry in the dairy industry.

Pneumonia due to Pseudomonas aeruginosa: the levofloxacin clinical trials experience.

PubMed

Tennenberg, Alan M; Davis, Neelam B; Wu, Shu-Chen; Kahn, James

2006-05-01

Respiratory infections caused by Pseudomonas aeruginosa present significant treatment challenges, including that of overcoming intrinsic and adaptive resistance by these organisms. The fluoroquinolones may provide an effective option for treating these infections. In this analysis, we report on the efficacy of levofloxacin in the treatment of community-acquired pneumonia (CAP) and nosocomial pneumonia caused by P. aeruginosa using information from nine clinical studies supported by Johnson & Johnson Pharmaceutical Research and Development (Raritan, NJ) or Ortho-McNeil Pharmaceutical (Raritan, NJ). From these studies, a total of 36 patients were identified with pneumonia caused by P. aeruginosa and treated with levofloxacin (750 mg or 500 mg). For patients diagnosed with nosocomial pneumonia, levofloxacin treatment achieved a 64.7% (11/17) clinical success rate, compared with 41.2% (7/17) with comparator treatment (imipenem/cilastatin followed by ciprofloxacin) in the microbiologically evaluable population. Eradication rates were 58.8% with levofloxacin treatment vs. 29.4% with comparator (95% CI, -64.2 to 5.4). For levofloxacin-treated CAP patients with P. aeruginosa infections (n = 19), clinical success and microbiological eradication rates in the microbiologically evaluable population were 89.5% and 78.9%, respectively. Several limitations of this analysis exist including that this was a retrospective evaluation that pooled data from multiple studies with varying protocols, the number of patients included was limited, and the nosocomial pneumonia patients used adjunctive therapy with an antipseudomonal beta-lactam in most cases. Nonetheless, these findings suggest that levofloxacin may play a role in the treatment of these difficult respiratory infections.

[Methods for evaluating diagnostic tests in Enfermedades Infecciosas y Microbiología Clínica].

PubMed

Ramos, J M; Hernández, I

1998-04-01

In the field of infectious diseases and clinical microbiology, the evaluation of diagnostic tests (DT) is an important research area. The specific difficulties of this type of research has motivated that have not caught the severity methodological of others areas of clinical research. This article try to asses and characterize the methodology of articles about DT published in Enfermedades Infecciosas y Microbiología Clínica (EIMC) journal. Forty-five articles was selected in the EIMC journal during the 1990-1996 period, because of determinate the sensitivity and specificity of different DT. Methodological standards, extensively accepted was used. In all of articles, except one (98%) the gold standard was specified yours use, however in 4 studies (9%) include the DT in the gold standard (incorporation bias). The correct description of DT was reported in 75% of cases, but only in 11% cases the reproducibility of test was evaluated. The description of source of reference population, standard of inclusion and spectrum of composition was described in 58, 33 and 40% of articles, respectively. In 33% of studies presented workup bias, only 6% commented blind-analysis of results, and 11% presented indeterminate test results. Half of the studies reported test indexes for clinical subgroups, only one article (2%) provided numerical precision for test indexes, and only 7% reported receiver operating characteristics curves. The methodological quality of DT research in the EIMC journal may improve in different aspects of design and presentation of results.

Evaluation of Small System Filtration Technologies for the Treatment of Color, Disinfection ByProducts and Microbiological Contaminants in Surface Water

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) National Risk Management Research Laboratory (NRMRL) evaluated various filtration systems at the EPA T&E Facility in Cincinnati, Ohio and at a field site in Ely, Minnesota (MN) in collaboration with the Minnesota Department of Health...

Antimicrobial efficacy of 0·05% cetylpyridinium chloride mouthrinses.

PubMed

Sreenivasan, P K; Haraszthy, V I; Zambon, J J

2013-01-01

This study evaluated the antimicrobial activity of two commercially available 0·05% cetylpyridinium chloride (CPC) mouthrinses with or without alcohol and examined its antimicrobial activity on oral bacterial species including fresh clinical isolates compared to a chlorhexidine mouthrinse and a control fluoride mouthrinse without CPC. Two different approaches were used to evaluate antimicrobial activity. First, the minimum inhibitory concentration (MIC) was determined for each mouthrinse against a panel of 25 micro-organisms including species associated with dental caries, gingivitis and periodontitis. Second, supragingival dental plaque obtained from 15 adults was incubated with the four mouthrinses to evaluate antimicrobial activity on micro-organisms in oral biofilms. Both CPC mouthrinses exhibited lower MIC's, that is, greater antimicrobial activity, against oral Gram-negative bacteria especially periodontal pathogens and species implicated in halitosis such as Aggregatibacter actinomycemcomitans, Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, Prevotella intermedia and Solobacterium moorei than the control mouthrinse. Ex-vivo tests on supragingival plaque micro-organisms demonstrated significantly greater antimicrobial activity by the CPC mouthrinses (>90% killing, P < 0·001) and the chlorhexidine rinse (>98% killing, P < 0·05) compared to the control fluoride mouthrinse. Whilst the chlorhexidine mouthrinse was most effective, mouthrinses containing 0·05% CPC formulated with or without alcohol demonstrated broad-spectrum antimicrobial activity against both laboratory strains and supragingival plaque bacteria compared to a control mouthrinse without CPC. These in vitro and ex-vivo studies provide a biological rationale for previous clinical studies demonstrating the efficacy of CPC mouthrinses in reducing supragingival plaque and plaque-associated gingivitis. © 2012 The Society for Applied Microbiology.

Spoilt for choice: A critical review on the chemical and biological assessment of current wastewater treatment technologies.

PubMed

Prasse, Carsten; Stalter, Daniel; Schulte-Oehlmann, Ulrike; Oehlmann, Jörg; Ternes, Thomas A

2015-12-15

The knowledge we have gained in recent years on the presence and effects of compounds discharged by wastewater treatment plants (WWTPs) brings us to a point where we must question the appropriateness of current water quality evaluation methodologies. An increasing number of anthropogenic chemicals is detected in treated wastewater and there is increasing evidence of adverse environmental effects related to WWTP discharges. It has thus become clear that new strategies are needed to assess overall quality of conventional and advanced treated wastewaters. There is an urgent need for multidisciplinary approaches combining expertise from engineering, analytical and environmental chemistry, (eco)toxicology, and microbiology. This review summarizes the current approaches used to assess treated wastewater quality from the chemical and ecotoxicological perspective. Discussed chemical approaches include target, non-target and suspect analysis, sum parameters, identification and monitoring of transformation products, computational modeling as well as effect directed analysis and toxicity identification evaluation. The discussed ecotoxicological methodologies encompass in vitro testing (cytotoxicity, genotoxicity, mutagenicity, endocrine disruption, adaptive stress response activation, toxicogenomics) and in vivo tests (single and multi species, biomonitoring). We critically discuss the benefits and limitations of the different methodologies reviewed. Additionally, we provide an overview of the current state of research regarding the chemical and ecotoxicological evaluation of conventional as well as the most widely used advanced wastewater treatment technologies, i.e., ozonation, advanced oxidation processes, chlorination, activated carbon, and membrane filtration. In particular, possible directions for future research activities in this area are provided. Copyright © 2015 Elsevier Ltd. All rights reserved.

Symptomatic and asymptomatic apical periodontitis associated with red complex bacteria: clinical and microbiological evaluation.

PubMed

Buonavoglia, Alessio; Latronico, Francesca; Pirani, Chiara; Greco, Maria Fiorella; Corrente, Marialaura; Prati, Carlo

2013-01-01

In this study, the association of red complex (RC) bacteria that include Treponema denticola, Tannerella forsythia and Porphyromonas gingivalis with acute, exacerbated or chronic apical periodontitis was evaluated. Seventy-one patients with periapical disease were evaluated by clinical examination and microbiological samples obtained from the root canals were analyzed by a polymerase chain reaction assay. Twenty-one (29.6%) samples were positive for RC bacteria, with T. denticola, T. forsythia and P. gingivalis being detected in 14 (19.7%), 10 (14.1%) and 6 (8.5%) samples, respectively. RC bacteria were mainly associated with acute apical periodontitis (29.2%) and phoenix abscess (63.2%), while they were only sporadically detected (7.1%) in patients with chronic apical periodontitis. Generally, RC bacteria were associated with pain and a higher frequency of intracanalar/intrasulcular pus drainage. Involvement of RC bacteria in symptomatic periapical disease should be suspected in the presence of particularly severe clinical pain and pus drainage.

The effect of a vaginal suppository formulation of dill (Anethum graveolens) in comparison to clotrimazole vaginal tablet on the treatment of vulvovaginal candidiasis.

PubMed

Saghafi, Nafiseh; Karjalian, Maryam; Ghazanfarpour, Masumeh; Khorsand, Imaneh; Rakhshandeh, Hassan; Mirteimouri, Masumeh; Babakhanian, Masoudeh; Khadivzadeh, Talat; Najafzadeh, Mohammad Javad; Ghorbani, Ahmad; Pourali, Leila; Bahman, Sara

2018-03-19

The goal of this study was to compare the effect of Anethum graveolens (dill) vaginal suppositories and 100 mg clotrimazole vaginal tablets on vulvovaginal Candidiasis. This study was a single centre, single-blind, randomised, placebo-controlled trial, in which 60 women with microbiology-confirmed vulvovaginal candidiasis were randomly assigned to dill and clotrimazole groups. At the end of the study, the estimated prevalence of leucorrhoea, burning, and itching was 23%, 23% and 20% in dill users, respectively. This figure was 20%, 10% and 16.7% for the clotrimazole group, respectively. The difference between the two groups was not significant. 13% of suppository patients, compared with 10% of clotrimazole-treatment patients, had a positive culture, which was not significant (p = .68). According to findings, 2% dill vaginal suppositories were as effective as clotrimazole vaginal tablets in reducing both clinical and microbiological symptoms of Candidiasis. Studies with larger sample sizes are required to confirm current findings. Impact statement What is already known on the subject? Based on results from in vivo and in vitro animal studies, dill (Anethum graveolens) has anti-candida activity. What do the results of this study add? It appears that 2% dill vaginal suppositories were as effective as 100 mg clotrimazole vaginal tablets in reducing both the clinical and microbiological symptoms. What are the implications of these findings for clinical practice and further research? Obstetricians and gynaecologists can offer dill as a useful alternative to chemical drugs, especially in women who are often interested in herbal medicine, or in women who are resistant or are not allowed to use antifungal drugs.

Factors Influencing the Microbial Composition of Metalworking Fluids and Potential Implications for Machine Operator's Lung

PubMed Central

Murat, Jean-Benjamin; Grenouillet, Frédéric; Penven, Emmanuelle; Batchili, Adam; Dalphin, Jean-Charles; Thaon, Isabelle; Millon, Laurence

2012-01-01

Hypersensitivity pneumonitis, also known as “machine operator's lung” (MOL), has been related to microorganisms growing in metalworking fluids (MWFs), especially Mycobacterium immunogenum. We aimed to (i) describe the microbiological contamination of MWFs and (ii) look for chemical, physical, and environmental parameters associated with variations in microbiological profiles. We microbiologically analyzed 180 MWF samples from nonautomotive plants (e.g., screw-machining or metal-cutting plants) in the Franche-Comté region in eastern France and 165 samples from three French automotive plants in which cases of MOL had been proven. Our results revealed two types of microbial biomes: the first was from the nonautomotive industry, showed predominantly Gram-negative rods (GNR), and was associated with a low risk of MOL, and the second came from the automotive industry that was affected by cases of MOL and showed predominantly Gram-positive rods (GPR). Traces of M. immunogenum were sporadically detected in the first type, while it was highly prevalent in the automotive sector, with up to 38% of samples testing positive. The use of chromium, nickel, or iron was associated with growth of Gram-negative rods; conversely, growth of Gram-positive rods was associated with the absence of these metals. Synthetic MWFs were more frequently sterile than emulsions. Vegetable oil-based emulsions were associated with GNR, while mineral ones were associated with GPR. Our results suggest that metal types and the nature of MWF play a part in MWF contamination, and this work shall be followed by further in vitro simulation experiments on the kinetics of microbial populations, focusing on the phenomena of inhibition and synergy. PMID:22057869

[A day in Spanish microbiology. Descriptive study of the activity of the clinical microbiology departments].

PubMed

Prieto, J; García-Rodríguez, Ja; Barberán, J; Granizo, Jj; Rodicio, Mp; González, J

2008-12-01

The laboratory is an essential part of the work in the Clinical Microbiology Department. This study has aimed to measure the activity of these laboratories. A survey was self-administered on the activity occurring during one work day by each hospital in October 2007. Thirty six hospitals reported 14,076 tests. Serology was the most frequently reported test (30.3%) followed by urine culture (27.8 %), blood tests (13.2 %), respiratory tract samples (8%), feces (7.1%), urethral (5.8%), skin (5.3%) and cerebrospinal fluid (2.6%). According to species, 73.2% of the isolates were bacteria (22.9 % were positive), 8.9% were virus (17% positive), fungi 8.1% (25.2% positive), and 5.5% mycobacterias (5.9% were positive) and parasite 4.5% (12.5% positive). Susceptibility test were performed by automatic methods (62.3%) followed by diffusion test (27.1%) and E-test (9.1%). A total of 5.6% of the susceptibility tests showed in vitro resistance to antibiotics. Fungi were identified in 108 isolates. Candida and Aspergillus were the most frequent genus (85.1% and 8.3%, respectively). Origins of the samples were: lower respiratory tract (32.4 %), genital tract (24.1 %), urine (10.2 %), blood (10.2 %) and skin (10.2 %). Twelve identification techniques were used, the most frequent being the morphological test (54.8%) and biochemical test (39.7%). Broken down by departments, 20.4% were sent from the ICU, 16.7% from surgery, 29.6% from medicine and 18.5% from primary care. Although the workload of the laboratories has been measured in this work, aspects such as specimen manipulation, clinical advice and research were not considered.

[Evaluation of the status of patients with severe infection, criteria for intensive care unit admittance. Spanish Society for Infectious Diseases and Clinical Microbiology. Spanish Society of Intensive and Critical Medicine and Coronary Units].

PubMed

Olaechea, Pedro M; Alvarez-Lerma, Francisco; Sánchez, Miguel; Torres, Antonio; Palomar, Mercedes; Fernández, Pedro; Miró, José M; Cisneros, José Miguel; Torres, Manuel

2009-06-01

Recent studies have shown that early attention in patients with serious infections is associated with a better outcome. Assistance in intensive care units (ICU) can effectively provide this attention; hence patients should be admitted to the ICU as soon as possible, before clinical deterioration becomes irreversible. The objective of this article is to compile the recommendations for evaluating disease severity in patients with infections and describe the criteria for ICU admission, updating the criteria published 10 years ago. A literature review was carried out, compiling the opinions of experts from the Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC, Spanish Society for Infectious Diseases and Clinical Microbiology) and the Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias (SEMICYUC, Spanish Society for Intensive Medicine, Critical Care and Coronary Units) as well as the working groups for infections in critically ill patients (GEIPC-SEIMC and GTEI-SEMICYUC). We describe the specific recommendations for ICU admission related to the most common infections affecting patients, who will potentially benefit from critical care. Assessment of the severity of the patient's condition to enable early intensive care is stressed.

Effects of Nonsurgical Periodontal Therapy on Clinical Response, Microbiological Profile, and Glycemic Control in Malaysian Subjects with Type 1 Diabetes

PubMed Central

Buzinin, Samira Mukhtar; Alabsi, Aied Mohammed; Tan, Alexander Tong Boon

2014-01-01

The association between diabetes mellitus and chronic periodontal disease has long been established. Most of the researches linking these two very common chronic diseases were based on type 2 diabetes mellitus and chronic periodontal disease. However, this study was conducted to investigate the association between type 1 diabetes and chronic periodontal disease in Malaysian subjects. Forty-one Malaysian subjects, of which 20 subjects were type 1 diabetics and with chronic periodontal disease (test group) and 21 subjects with only chronic periodontal disease (control group), were included in the study. Periodontal parameters and plaque samples for microbiological evaluation were done at baseline, 2 and 3 months after nonsurgical periodontal therapy. Blood samples were taken from only the test group and evaluated for HbA1c at baseline and 3 months after periodontal therapy. There were no statistically significant difference in periodontal parameters between groups (P>0.05) and no significant improvement in the level of HbA1c in the test group. Microbiological studies indicated that there were significant reductions in the levels of the tested pathogens in both groups. The results of our study were similar to the findings of several other studies that had been done previously. PMID:25147841

Evaluation of efficacy of photodynamic therapy as an adjunct to nonsurgical periodontal therapy in treatment of chronic periodontitis patients: A clinico-microbiological study.

PubMed

Raj, K Ravi; Musalaiah, Svvs; Nagasri, M; Kumar, P Aravind; Reddy, P Indeevar; Greeshma, M

2016-01-01

Photodynamic therapy (PDT) is a local noninvasive treatment modality without side effects caused by antibiotics. The aim of this study was to evaluate the efficacy of adjunctive use of PDT with scaling and root planing as compared with SRP alone in the treatment of chronic periodontitis. Twenty participants with chronic periodontitis having probing pocket depths (PDs) of ≥5 mm were selected for the study. Patients were randomly divided into control group and test group with ten patients in each group. Full-mouth SRP was performed in both the groups, followed by PDT in test group. Assessment of plaque index (PI), gingival index (GI), PD, and clinical attachment level (CAL) was done at baseline and after 3 months. Microbiological assessment of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola was done by polymerase chain reaction (PCR) at baseline and 3 months after the therapy. There was a significant reduction in PI, GI, PD, CAL, and microbiologic parameters in test group, following SRP and PDT, when compared with SRP alone in control group. PDT in conjunction with SRP has shown additional improvement in periodontal parameters when compared to SRP alone and has a beneficial effect in chronic periodontitis patients.

A combination of grapefruit seed extract and concentrated cranberry juice as a potential antimicrobial preservative for the improvement of microbiological stability of hypromellose gel.

PubMed

Bernatoniene, Jurga; Keraitė, Rasa; Masteiková, Ruta; Pavilonis, Alvydas; Savickas, Arūnas

2013-10-01

Aqueous hypromellose gels are not microbiologically stable - they show signs of microorganism growth during storage. To extend the shelf-life of the gels, antimicrobial preservatives are needed. Some substances of plant origin are known for their antimicrobial properties, and thus they may be used as an alternative to synthetic preservatives. Therefore, the aim of this study was to evaluate the microbiological stability of aqueous hypromellose gel and the effectiveness of natural substances - grapefruit seed extract (GSE), concentrated cranberry juice, and a combination thereof - on the antimicrobial protection of the gel. The evaluation of the antimicrobial activity of GSE and cranberry juice showed that their antimicrobial effects differed. Both cranberry juice and GSE inhibited the growth of the standard gram-positive and gram-negative bacteria, but the effect of GSE was significantly stronger. Candida albicans was sensitive only to GSE. For this reason, in order to affect all the microorganisms studied, either a combination of 0.7% GSE and 10% cranberry juice, or 5% GSE alone may be used. The combination of GSE and cranberry juice was effective only in acidic medium (pH being 2.5-5), while the antimicrobial effect of GSE was not dependent on the pH value.

Evaluation of control over the microbiological contamination of carcasses in a lamb carcass dressing process operated with or without pasteurizing treatment.

PubMed

Milios, K; Mataragas, M; Pantouvakis, A; Drosinos, E H; Zoiopoulos, P E

2011-03-30

The aim of this study was to quantify the hygienic status of a lamb slaughterhouse by means of multivariate statistical analysis, to demonstrate how the microbiological data could be exploited to improve the lamb slaughter process by constructing control charts and to evaluate the potential effect of an intervention step such as steam application on the microbiological quality of lamb carcasses. Results showed that pelt removal and evisceration were hygienically uncontrolled. TVC and Enterobacteriaceae progressively increased from the stage 'after pelt removal of hind and forelegs/before final pulling' to the stage 'after evisceration/before pluck removal' thus indicating possible deposition of microorganisms during these operations. It seems that the processing stages of freshly produced carcasses were better distinguished by Enterobacteriaceae, with evisceration contributing mostly to the final Enterobacteriaceae counts. Application of steam during the lamb slaughter process reduced microbial counts without adverse effects on the organoleptic characteristics of the carcasses. Moreover, the construction of control charts showed that decontamination with steam contributed to the maintenance of an in control process compared to that before the application of steam, suggesting the potential use of steam as an intervention step during the lamb slaughter process. Copyright © 2011 Elsevier B.V. All rights reserved.

Evaluation of fluorescence in situ hybridisation (FISH) for the detection of fungi directly from blood cultures and cerebrospinal fluid from patients with suspected invasive mycoses.

PubMed

Da Silva, Roberto Moreira; Da Silva Neto, João Ricardo; Santos, Carla Silvana; Frickmann, Hagen; Poppert, Sven; Cruz, Kátia Santana; Koshikene, Daniela; De Souza, João Vicente Braga

2015-01-31

The aim of this study was to evaluate the diagnostic performance of in-house FISH (fluorescence in situ hybridisation) procedures for the direct identification of invasive fungal infections in blood cultures and cerebrospinal fluid (CSF) samples and to compare these FISH results with those obtained using traditional microbiological techniques and PCR targeting of the ITS1 region of the rRNA gene. In total, 112 CSF samples and 30 positive blood cultures were investigated by microscopic examination, culture, PCR-RFLP and FISH. The sensitivity of FISH for fungal infections in CSF proved to be slightly better than that of conventional microscopy (India ink) under the experimental conditions, detecting 48 (instead of 46) infections in 112 samples. The discriminatory powers of traditional microbiology, PCR-RFLP and FISH for fungal bloodstream infections were equivalent, with the detection of 14 fungal infections in 30 samples. However, the mean times to diagnosis after the detection of microbial growth by automated blood culture systems were 5 hours, 20 hours and 6 days for FISH, PCR-RFLP and traditional microbiology, respectively. The results demonstrate that FISH is a valuable tool for the identification of invasive mycoses that can be implemented in the diagnostic routine of hospital laboratories.

Evaluation of microbiological accumulation capability of the commercial sponge Spongia officinalis var. adriatica (Schmidt) (Porifera, Demospongiae).

PubMed

Stabili, Loredana; Licciano, Margherita; Longo, Caterina; Corriero, Giuseppe; Mercurio, Maria

2008-05-01

This study was carried out to evaluate the microbiological accumulation capability of the demosponge Spongia officinalis var. adriatica. Six microbiological parameters were researched in two sampling periods in the water and in reared sponge samples coming from sites with different degrees of microbial contamination: an off-shore fish farm displaced off the Apulian coast (Southern Adriatic Sea) and a no-impacted area displaced into the Marine Protected Area of Porto Cesareo (Apulian coast-Ionian Sea). We detected the density of culturable heterotrophic bacteria by spread plate on marine agar, total culturable bacteria at 37 degrees C on Plate Count Agar and vibrios on thiosulphate-citrate-bile-sucrose-salt (TCBS) agar. Total and fecal coliforms as well as fecal streptococci concentrations were detected by the MPN method. Bacterial densities were always higher in the sponge homogenates compared with the corresponding seawater in the sampling points and in both sampling periods. As regard vibrios, total culturable bacteria at 37 degrees C and fecal streptococci concentrations, the highest values were observed in the sponge samples coming from the off-shore fish farm during the summer period. The ability of Spongia officinalis var. adriatica to accumulate the microbial pollution indicators suggests that this species can be employed as a bioindicator for monitoring water quality.

[Surveillance of the sanitary conditions of a public swimming pool in the city of Palermo (Italy)].

PubMed

Maida, Carmelo Massimo; Di Benedetto, Maria Antonella; Firenze, Alberto; Calamusa, Giuseppe; Di Piazza, Florinda; Milici, Maria Eleonora; Romano, Nino

2008-01-01

In a previous study we evaluated the microbiological quality of water of seven pools in the city of Palermo through evaluation of bacterial indicators of faecal contamination and of protozoa (Giardia and Cryptosporidium). In this study we also searched for the presence of fungi in two swimming pools of a public swimming facility in the same city. Samples were collected from both pools, their filtration systems and floor surfaces of the facility. Chemical-physical and microbiological examination of water of the two pools have shown that quality of water depends on the concentration of residual free chlorine and on the number of bathers in the pool. The values of four microbiological parameters (bacterial load at 22 degrees C and 36 degrees C, presence of coagulase-negative Staphylococci and Pseudomonas spp.) increased with diminishing chlorine concentrations and with increasing number of pool users. Faecal bacteria, Giardia and Cryptosporidium were not found. On the other hand, various fungi were isolated from floor surfaces and pool water even in the presence of optimal chlorine concentrations. This study confirms the importance of regular maintenance of pool disinfection systems and suggests the need to search for other micro-organisms not included in the current legislation (Giardia, Cryptosporidium and fungi).

Are the defined substrate-based methods adequate to determine the microbiological quality of natural recreational waters?

PubMed

Valente, Marta Sofia; Pedro, Paulo; Alonso, M Carmen; Borrego, Juan J; Dionísio, Lídia

2010-03-01

Monitoring the microbiological quality of water used for recreational activities is very important to human public health. Although the sanitary quality of recreational marine waters could be evaluated by standard methods, they are time-consuming and need confirmation. For these reasons, faster and more sensitive methods, such as the defined substrate-based technology, have been developed. In the present work, we have compared the standard method of membrane filtration using Tergitol-TTC agar for total coliforms and Escherichia coli, and Slanetz and Bartley agar for enterococci, and the IDEXX defined substrate technology for these faecal pollution indicators to determine the microbiological quality of natural recreational waters. ISO 17994:2004 standard was used to compare these methods. The IDEXX for total coliforms and E. coli, Colilert, showed higher values than those obtained by the standard method. Enterolert test, for the enumeration of enterococci, showed lower values when compared with the standard method. It may be concluded that more studies to evaluate the precision and accuracy of the rapid tests are required in order to apply them for routine monitoring of marine and freshwater recreational bathing areas. The main advantages of these methods are that they are more specific, feasible and simpler than the standard methodology.

Effect of a triclosan/PVM/MA copolymer/fluoride dentifrice on volatile sulfur compounds in vitro.

PubMed

Pilch, S; Williams, M I; Cummins, D

2005-01-01

The objective of the investigation was to document the in vitro efficacy of a triclosan/PVM/MA copolymer/fluoride (TCF) dentifrice against the formation of volatile sulfur compounds (VSC) as well as the growth of H2S-producing bacteria. Clinical studies using organoleptic judges, gas chromatography, or a portable sulfide monitor have generally been employed in the assessment of treatments for the control of oral malodor. However, these studies are not appropriate for screening purposes because of the expense and time required. An in vitro method was developed for the purpose of screening new compounds, agents or formulations for their ability to control VSC formation and for determining bio-equivalence of efficacy when implementing changes in existing formulations. The method combines basic microbiological methods, dynamic flow cell techniques and head space analysis. The in vitro VSC method was validated by comparing the efficacy of two dentifrices containing TCF with a control fluoride dentifrice as the TCF products have been clinically proven to control oral malodor. In the validation studies, the TCF-containing dentifrices were significantly better (P < 0.05) than the control dentifrice in inhibiting VSC formation and reducing H(2)S-producing bacteria. For example, when compared with baseline, the TCF dentifrices reduced VSC formation between 42 and 49% compared with the control dentifrice which reduced VSC formation 3%. There was no significant difference (P > 0.05) between the two TCF dentifrice formulations. Using an in vitro breath VSC model, it has been demonstrated that two variants of a dentifrice containing triclosan, PVM/MA copolymer and fluoride have efficacy that is significantly better than a control fluoridated dentifrice and that there is no significant difference between the triclosan/PVM/MA copolymer/fluoride dentifrice variants.

In vitro growth and cell wall degrading enzyme production by Argentinean isolates of Macrophomina phaseolina, the causative agent of charcoal rot in corn.

PubMed

Ramos, Araceli M; Gally, Marcela; Szapiro, Gala; Itzcovich, Tatiana; Carabajal, Maira; Levin, Laura

Macrophomina phaseolina is a polyphagous phytopathogen, causing stalk rot on many commercially important species. Damages caused by this pathogen in soybean and maize crops in Argentina during drought and hot weather have increased due its ability to survive as sclerotia in soil and crop debris under non-till practices. In this work, we explored the in vitro production of plant cell wall-degrading enzymes [pectinases (polygalacturonase and polymethylgalacturonase); cellulases (endoglucanase); hemicellulases (endoxylanase) and the ligninolytic enzyme laccase] by several Argentinean isolates of M. phaseolina, and assessed the pathogenicity of these isolates as a preliminary step to establish the role of these enzymes in M. phaseolina-maize interaction. The isolates were grown in liquid synthetic medium supplemented with glucose, pectin, carboxymethylcellulose or xylan as carbon sources and/or enzyme inducers and glutamic acid as nitrogen source. Pectinases were the first cell wall-degrading enzymes detected and the activities obtained (polygalacturonase activity was between 0.4 and 1.3U/ml and polymethylgalacturonase between 0.15 and 1.3U/ml) were higher than those of cellulases and xylanases, which appeared later and in a lesser magnitude. This sequence would promote initial tissue maceration followed by cell wall degradation. Laccase was detected in all the isolates evaluated (activity was between 36U/l and 63U/l). The aggressiveness of the isolates was tested in maize, sunflower and watermelon seeds, being high on all the plants assayed. This study reports for the first time the potential of different isolates of M. phaseolina to produce plant cell wall-degrading enzymes in submerged fermentation. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Amish burn ointment and burdock leaf dressings: assessments of antimicrobial and cytotoxic activities.

PubMed

Rieman, Mary T; Neely, Alice N; Boyce, Steven T; Kossenjans, William J; Durkee, Paula J; Zembrodt, Jacquelyn M; Puthoff, Barbara K; Kagan, Richard J

2014-01-01

Amish burn wound ointment (ABO) contains honey, lanolin, oils, glycerin, bees wax, and other natural additives. Although there are many anecdotal reports that this ointment covered with a burdock leaf (BL) dressing promotes burn wound healing, little scientific testing of this treatment has occurred. The goal of this study was to evaluate in vitro some of the components of this treatment modality for antimicrobial and cytotoxic activities. The ABO was tested for sterility using standard microbiological techniques. Because of the semisolid, lipid-based nature of the salve, the at-use product could not be tested in bioassays. Samples of BL and the dry ingredients (DI) used in the ointment were provided by the Amish vendor. Aqueous extracts of the DI and of the BL were prepared and freeze dried. The freeze-dried extracts were reconstituted, filtered, and tested separately on keratinocyte and fibroblast cell cultures for cytotoxicity (growth inhibition assay) and against a panel of susceptible and resistant microbes for antimicrobial activity (Nathan's agar-well diffusion assay) in a series of concentrations (% wt/vol). Neither DI nor BL extracts demonstrated antimicrobial activity against any of organisms tested. The DI extract inhibited growth of both keratinocytes and fibroblasts at the 0.1% concentration. The 0.1 and 0.03% concentrations of the BL extract were cytotoxic to both keratinocytes and fibroblasts. Although tests for microbial growth from the at-use preparation of the ABO were negative, extracts of the DI and BL did not demonstrate any antimicrobial activity. Additionally, both extracts inhibited the growth of skin cells in vitro at higher concentrations. These results suggest caution in the use of ABO and BL dressings if there is more than a minimal risk of complications from the burn injury.

In vitro evaluation of BacT/Alert FA blood culture bottles and T2Candida assay for the detection of Candida in the presence of antifungals.

PubMed

Beyda, Nicholas D; Amadio, Jonathan; Rodriguez, Jose R; Malinowski, Karen; Garey, Kevin W; Wanger, Audrey; Ostrosky-Zeichner, Luis

2018-06-13

The T2Candida assay is a novel, non-culture based assay for the diagnosis of candidemia directly from whole blood. The impact of antifungals on the performance of the T2Candida assay and blood culture bottles have not been well described. In this study, the performance of the T2Candida assay was compared to that of blood culture in detecting Candida spp. in spiked blood cultures with or without the presence of antifungals. Clinical bloodstream isolates of Candida spp. were inoculated into human whole blood at low (1 - 5 cells/mL) and high (10-50 cells/mL) concentrations with or without presence of caspofungin and fluconazole. Time to detection (TTD) was assessed for prepared samples using BacTAlert FA aerobic blood culture bottles or the T2Candida assay. In the absence of antifungals, T2Candida assay sensitivity was comparable to that of blood culture at both the low and high inoculum (95% vs. 97.5% and 100% vs. 100%, respectively) and had an average TTD that was significantly faster (5.1 hrs vs 27.2 - 30 hrs, respectively). Neither caspofungin nor fluconazole was observed to impact the sensitivity or TTD of the T2Candida assay, while fluconazole reduced overall blood culture sensitivity by 7.5% - 12.5% (at low and high inoculum, respectively) and significantly prolonged the TTD of C. albicans, C. tropicalis , and C. parapsilosis by 14.8 - 67 hrs. Neither caspofungin nor fluconazole impacted the performance of the T2Candida assay in-vitro and may be useful for the diagnosis of candidemia in patients receiving antifungal therapy. Copyright © 2018 American Society for Microbiology.

Synergistic Interactions between Hepatitis B Virus RNase H Antagonists and Other Inhibitors.

PubMed

Lomonosova, Elena; Zlotnick, Adam; Tavis, John E

2017-03-01

Combination therapies are standard for management of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections; however, no such therapies are established for human hepatitis B virus (HBV). Recently, we identified several promising inhibitors of HBV RNase H (here simply RNase H) activity that have significant activity against viral replication in vitro Here, we investigated the in vitro antiviral efficacy of combinations of two RNase H inhibitors with the current anti-HBV drug nucleoside analog lamivudine, with HAP12, an experimental core protein allosteric modulator, and with each other. Anti-HBV activities of the compounds were tested in a HepG2-derived cell line by monitoring intracellular core particle DNA levels, and cytotoxicity was assessed by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. The antiviral efficiencies of the drug combinations were evaluated using the median-effect equation derived from the mass-action law principle and combination index theorem of Chou and Talalay. We found that combinations of two RNase H inhibitors from different chemical classes were synergistic with lamivudine against HBV DNA synthesis. Significant synergism was also observed for the combination of the two RNase H inhibitors. Combinations of RNase H inhibitors with HAP12 had additive antiviral effects. Enhanced cytotoxicity was not observed in the combination experiments. Because of these synergistic and additive effects, the antiviral activity of combinations of RNase H inhibitors with drugs that act by two different mechanisms and with each other can be achieved by administering the compounds in combination at doses below the respective single drug doses. Copyright © 2017 American Society for Microbiology.

Comparison of an In Vitro Diagnostic Next-Generation Sequencing Assay with Sanger Sequencing for HIV-1 Genotypic Resistance Testing.

PubMed

Tzou, Philip L; Ariyaratne, Pramila; Varghese, Vici; Lee, Charlie; Rakhmanaliev, Elian; Villy, Carolin; Yee, Meiqi; Tan, Kevin; Michel, Gerd; Pinsky, Benjamin A; Shafer, Robert W

2018-06-01

The ability of next-generation sequencing (NGS) technologies to detect low frequency HIV-1 drug resistance mutations (DRMs) not detected by dideoxynucleotide Sanger sequencing has potential advantages for improved patient outcomes. We compared the performance of an in vitro diagnostic (IVD) NGS assay, the Sentosa SQ HIV genotyping assay for HIV-1 genotypic resistance testing, with Sanger sequencing on 138 protease/reverse transcriptase (RT) and 39 integrase sequences. The NGS assay used a 5% threshold for reporting low-frequency variants. The level of complete plus partial nucleotide sequence concordance between Sanger sequencing and NGS was 99.9%. Among the 138 protease/RT sequences, a mean of 6.4 DRMs was identified by both Sanger and NGS, a mean of 0.5 DRM was detected by NGS alone, and a mean of 0.1 DRM was detected by Sanger sequencing alone. Among the 39 integrase sequences, a mean of 1.6 DRMs was detected by both Sanger sequencing and NGS and a mean of 0.15 DRM was detected by NGS alone. Compared with Sanger sequencing, NGS estimated higher levels of resistance to one or more antiretroviral drugs for 18.2% of protease/RT sequences and 5.1% of integrase sequences. There was little evidence for technical artifacts in the NGS sequences, but the G-to-A hypermutation was detected in three samples. In conclusion, the IVD NGS assay evaluated in this study was highly concordant with Sanger sequencing. At the 5% threshold for reporting minority variants, NGS appeared to attain a modestly increased sensitivity for detecting low-frequency DRMs without compromising sequence accuracy. Copyright © 2018 American Society for Microbiology.

Activity of Simulated Human Dosage Regimens of Meropenem and Vaborbactam against Carbapenem-Resistant Enterobacteriaceae in an In Vitro Hollow-Fiber Model.

PubMed

Sabet, Mojgan; Tarazi, Ziad; Rubio-Aparicio, Debora; Nolan, Thomas G; Parkinson, Jonathan; Lomovskaya, Olga; Dudley, Michael N; Griffith, David C

2018-02-01

The objective of these studies was to evaluate the exposures of meropenem and vaborbactam that would produce antibacterial activity and prevent resistance development in carbapenem-resistant Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae strains when tested at an inoculum of 10 8 CFU/ml. Thirteen K. pneumoniae isolates, three Enterobacter cloacae isolates, and one Escherichia coli isolate were examined in an in vitro hollow-fiber model over 32 h. Simulated dosage regimens of 1 to 2 g of meropenem with 1 to 2 g of vaborbactam, with meropenem administered every 8 h by a 3-h infusion based on phase 1 or phase 3 patient pharmacokinetic data, were studied in the model. A dosage of 2 g of meropenem in combination with 2 g of vaborbactam was bactericidal against K. pneumoniae , E. cloacae , and E. coli strains, with meropenem-vaborbactam MICs of up to 8 mg/liter. When the vaborbactam exposure was adjusted to the levels observed in patients enrolled in phase 3 trials (24-h free AUC, ∼550 mg · h/liter, versus 320 mg · h/liter in the phase 1 studies), 2 g of meropenem with 2 g of vaborbactam was also bactericidal against strains with meropenem-vaborbactam MICs of 16 mg/liter. In addition, this level of vaborbactam also suppressed the development of resistance observed using phase 1 exposures. In this pharmacodynamic model, exposures similar to 2 g of meropenem in combination with 2 g of vaborbactam administered every 8 h by a 3-h infusion in phase 3 trials produced antibacterial activity and suppressed the development of resistance against carbapenem-resistant KPC-producing strains of Enterobacteriaceae . Copyright © 2018 American Society for Microbiology.

Effects of Bacillus fermentation on the protein microstructure and anti-nutritional factors of soybean meal.

PubMed

Zheng, L; Li, D; Li, Z-L; Kang, L-N; Jiang, Y-Y; Liu, X-Y; Chi, Y-P; Li, Y-Q; Wang, J-H

2017-12-01

This study evaluated the effects of Bacillus fermentation on soybean meal protein (SBMP) microstructure and major anti-nutritional factors (ANFs) in soybean meal (SBM). The Bacillus siamensis isolate JL8 producing high yield of protease at 519·1 U g -1 was selected for the laboratory production of fermented soybean meal (FSBM). After 24 h fermentation, the FSBM showed better properties compared with those of SBM, the ANFs such as glycinin, β-conglycinin and trypsin inhibitor significantly decreased by 86·0, 70·3 and 95·01%, while in vitro digestibility and absorbability increased by 8·7 and 18·9% respectively. Scanning electron microscopy (SEM) image of fermented soybean meal protein showed smaller aggregates and looser network than that of SBMP. Secondary structure examination of proteins revealed fermentation significantly decreased the content of β-sheet structure by 43·2% and increased the random coil structure by 59·9%. It is demonstrated that Bacillus fermentation improved the nutritional quality of SBM through degrading ANFs and changing the microstructure of SBMP. There is limited information about the structural property changes of soybean protein during fermentation. In this study, physicochemical analysis of soybean meal protein showed evidence that the increase in in vitro digestibility and absorbability of fermented soybean meal reflected the decrease in β-conformation and destruction of original structure in soybean meal protein. The results directly gained the understanding of nutritional quality improvement of soybean meal by Bacillus fermentation, and supply the potential use of Bacillus siamensis for fermented soybean meal production. © 2017 The Society for Applied Microbiology.

Species identification of Aspergillus, Fusarium and Mucorales with direct surface analysis by matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

PubMed

De Carolis, E; Posteraro, B; Lass-Flörl, C; Vella, A; Florio, A R; Torelli, R; Girmenia, C; Colozza, C; Tortorano, A M; Sanguinetti, M; Fadda, G

2012-05-01

Accurate species discrimination of filamentous fungi is essential, because some species have specific antifungal susceptibility patterns, and misidentification may result in inappropriate therapy. We evaluated matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for species identification through direct surface analysis of the fungal culture. By use of culture collection strains representing 55 species of Aspergillus, Fusarium and Mucorales, a reference database was established for MALDI-TOF MS-based species identification according to the manufacturer's recommendations for microflex measurements and MALDI BioTyper 2.0 software. The profiles of young and mature colonies were analysed for each of the reference strains, and species-specific spectral fingerprints were obtained. To evaluate the database, 103 blind-coded fungal isolates collected in the routine clinical microbiology laboratory were tested. As a reference method for species designation, multilocus sequencing was used. Eighty-five isolates were unequivocally identified to the species level (≥99% sequence similarity); 18 isolates producing ambiguous results at this threshold were initially rated as identified to the genus level only. Further molecular analysis definitively assigned these isolates to the species Aspergillus oryzae (17 isolates) and Aspergillus flavus (one isolate), concordant with the MALDI-TOF MS results. Excluding nine isolates that belong to the fungal species not included in our reference database, 91 (96.8%) of 94 isolates were identified by MALDI-TOF MS to the species level, in agreement with the results of the reference method; three isolates were identified to the genus level. In conclusion, MALDI-TOF MS is suitable for the routine identification of filamentous fungi in a medical microbiology laboratory. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

Diagnostic performance of blood culture bottles for vitreous culture compared to conventional microbiological cultures in patients with suspected endophthalmitis.

PubMed

Kehrmann, Jan; Chapot, Valerie; Buer, Jan; Rating, Philipp; Bornfeld, Norbert; Steinmann, Joerg

2018-05-01

The purpose of this investigation was to evaluate the performance of blood culture bottles in comparison to conventional microbiological culture techniques in detecting causative microorganisms of endophthalmitis and to determine their anti-infective susceptibility profiles. All consecutive cases with clinically suspected endophthalmitis in a university-based ophthalmology department between January 2009 and December 2016 were analysed in this retrospective comparative case series. Samples from 247 patients with suspected endophthalmitis underwent microbiological diagnostic work-up. All three culture methods were performed from 140 vitreous specimens. Vitreous fluid specimens were inoculated in blood culture bottles, aerobic and anaerobic broth solutions, and on solid media. Anti-infective susceptibility profiles were evaluated by semi-automated methods and/or gradient diffusion methods. Microorganisms were grown in 82 of 140 specimens for which all methods were performed (59%). Microorganisms were more frequently grown from blood culture bottles (55%) compared to broth solution (45%, p = 0.007) and solid media (33%, p < 0.0001). Considerable differences in the performance among culture media were detected for fungal pathogens. All grown fungi were detected by blood culture bottles (11 of 11, 100%). Broth solution recovered 64% and solid media 46% of grown fungi. No Gram-positive bacterium was resistant to vancomycin and all Gram-negative pathogens except for one isolate were susceptible to third-generation cephalosporins. In suspected endophthalmitis patients, blood culture bottles have a higher overall pathogen detection rate from vitreous fluid compared to conventional microbiological media, especially for fungi. The initial intravitreal antibiotic therapy with vancomycin plus third-generation cephalosporins appears to be an appropriate treatment approach for bacterial endophthalmitis.

[Frequency of Candida in root canals of teeth with primary and persistent endodontic infections].

PubMed

Bernal-Treviño, Angel; González-Amaro, Ana María; Méndez González, Verónica; Pozos-Guillen, Amaury

Microbiological identification in endodontic infections has focused mainly on bacteria without giving much attention to yeasts, which, due to their virulence factors, can affect the outcomes of root canal treatment. To determine the frequency of Candida in anaerobic conditions in root canals with primary and persistent endodontic infection, as well as to evaluate a microbiological sampling method using aspiration compared to the traditional absorption method with paper points. Fifty microbiological samples were obtained from teeth of 47 patients requiring endodontic treatments, due to either primary or persistent infections. Two microbiological sampling methods were used: an aspiration method, and the traditional paper point absorption method. In each of these methods, two types of medium were used (M 1 -M 4 ). Samples were cultured under anaerobic conditions until reaching 0.5 McFarland turbidity, and then inoculated on Sabouraud dextrose, as well as on anaerobic enriched blood agar plates. Macroscopic and microscopic observations of the colonies were performed. The germ-tube test, growth on CHROMagar, and biochemical identification were performed on the isolated yeasts. Fungal infection was found in 18 (36%) samples out of the 50 teeth evaluated. In the 18 samples positive for fungal infection, 15 out of 36 (41.6%) teeth were taken from a primary infection, and 3 out of 14 (21.4%) from a persistent infection. The aspiration method using Sabouraud dextrose medium recovered a greater diversity of species. Yeasts frequency was higher in teeth with primary infections compared to teeth with persistent infections. The predominant yeast species was Candida albicans. The aspirating sampling method was more efficient in the recovery of Candida isolates than the traditional absorption method. Copyright © 2018 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

Careers in Microbiology...Horizons Unlimited

ERIC Educational Resources Information Center

Goldschmidt Millicent C.; Whitt, Dixie

1978-01-01

A broad range of present microbiological work is discussed in order to indicate the many possible careers now open in microbiology. Some areas are immunology, environmental microbiology, agricultural, industrial, and food microbiology, and space microbiology. An employment outlook is also given. (MDR)

78 FR 54643 - Proposed Information Collection Request; Comment Request; Laboratory Quality Assurance Evaluation...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-05

... certification responsibilities for the chemistry and microbiology laboratories that they oversee in their...--including an assessment of Proficiency Test results; and on-site audits at least triennially). Whereas 40...

Mechanisms and possible controls of the in utero Zika virus infection: Where is the Holy Grail?

PubMed

Fuwa, Kazumasa; Hayakawa, Satoshi

2017-02-01

Zika virus infection (ZVI) is a great concern for human health because it frequently causes fetal anomalies. Little is known about pathophysiology of ZVI because it has been regarded as a mild, no life-threatening infection. However, the latest endemic in South and Central America took attention of perinatologists, microbiologists, and pathologists. Both in vivo and in vitro studies suggest neurotropic nature of Zika virus but do not clarify viral kinetics during vertical transmissions. In this review, we focus on the clinical and microbiological natures ZVI for pregnant women especially how placental barriers are broken down. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Levofloxacin compared with imipenem/cilastatin followed by ciprofloxacin in adult patients with nosocomial pneumonia: a multicenter, prospective, randomized, open-label study.

PubMed

West, Mike; Boulanger, Bernard R; Fogarty, Charles; Tennenberg, Alan; Wiesinger, Barbara; Oross, Margaret; Wu, Shu-Chen; Fowler, Cynthia; Morgan, Nancy; Kahn, James B

2003-02-01

Therapy of nosocomial pneumonia is usually empiric and includes > or = 1 broad-spectrum antimicrobial agent. When considering the use of fluoroquinolones in these difficult-to-treat infections--in which drug delivery to the site of infection may be impaired or organisms with higher minimum inhibitory concentrations may be present--an agent should be chosen whose pharmacodynamics ensure maximal drug exposure. Use of the 750-mg dose of levofloxacin should enhance therapeutic benefit in patients with nosocomial pneumonia. The goal of this study was to compare the efficacy and safety of levofloxacin 750 mg and imipenem/cilastatin followed by ciprofloxacin in adult patients with nosocomial pneumonia. This was a multicenter, prospective, randomized, open-label trial conducted in North America. Patients were randomly assigned to 1 of 2 treatment arms: levofloxacin 750 mg QD given i.v. and then orally for 7 to 15 days or imipenem/cilastatin 500 mg to 1 g i.v. every 6 to 8 hours, followed by oral ciprofloxacin 750 mg every 12 hours for 7 to 15 days. Adjunctive antibacterial therapy was mandatory in patients with documented or suspected Pseudomonas aeruginosa or methicillin-resistant Staphylococcus aureus infection. The primary predefined outcome measure was the clinical response (cure, improvement, failure, or unable to evaluate) in microbiologically evaluable patients 3 to 15 days after the end of therapy. The study enrolled 438 adult patients (315 men, 123 women; mean [SD] age, 55.7 [20.04] years). Two hundred twenty patients received levofloxacin, and 218 received the comparator regimen. Demographic and baseline clinical characteristics were similar in the intent-to-treat and clinically evaluable populations. In patients evaluable for microbiologic efficacy, clinical success (cure or improvement) was achieved in 58.1% (54/93) of patients who received levofloxacin, compared with 60.6% (57/94) of patients who received the comparator regimen (95% CI, -12.0 to 17.2). Similar clinical results were seen in patients evaluable for clinical efficacy and in the intent-to-treat population. In the 187 patients evaluable for microbiologic efficacy, eradication was achieved in 66.7% (62/93) of patients receiving levofloxacin and 60.6% (57/94) of patients receiving the comparator regimen (95% CI, -20.3 to 8.3). In this study, levofloxacin was at least as effective and was as well tolerated as imipenem/cilastatin followed by ciprofloxacin in adult patients with nosocomial pneumonia, as demonstrated by comparable clinical and microbiologic success rates.

Impact of heavy smoking on the clinical, microbiological and immunological parameters of patients with dental implants: a prospective cross-sectional study.

PubMed

Ata-Ali, Javier; Flichy-Fernández, Antonio Juan; Alegre-Domingo, Teresa; Ata-Ali, Fadi; Peñarrocha-Diago, Miguel

2016-11-01

The aim of the present study was to investigate how heavy smoking influences the clinical, microbiological, and host-response characteristics in peri-implant sulcus fluid of patients with healthy dental implants. A total of 29 individuals with 74 dental implants were included in the present study; 20 implants were in heavy smokers and 54 were in non-smokers. The modified gingival index, modified plaque index, and probing pocket depth were evaluated. Periodontopathogenic bacteria Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis were evaluated, together with the total bacterial load. Peri-implant sulcus fluid samples were analyzed for the quantification of interleukin-8, interleukin-1β, interleukin-6, interleukin-10, and tumor necrosis factor-α. No significant differences in the clinical parameters evaluated were found between the groups, although smokers had poorer peri-implant parameters. Among the smokers, subgingival microbiota was composed of a greater number of periodontal pathogens; these differences were not statistically significant. Smokers showed a greater expression of interleukin-1β, interleukin-6, interleukin-10, and tumor necrosis factor-α, but interleukin-8 was slightly higher among non-smokers, but not significantly. Although smokers presented deeper probing depths, bleeding on probing, and peri-implant microbiota composed of a greater number of periodontal pathogens than in non-smoking patients, these data did not show significant differences. In the present study, and in relation to the samples analyzed, smoking alone did not influence the immunological and microbiological parameters in dental implants with healthy peri-implant tissues. Further studies with larger samples are required to better evaluate the influence of smoking on dental implants. © 2015 Wiley Publishing Asia Pty Ltd.

Bacterial Populations Associated with Smokeless Tobacco Products

PubMed Central

Han, Jing; Sanad, Yasser M.; Deck, Joanna; Sutherland, John B.; Li, Zhong; Walters, Matthew J.; Duran, Norma; Holman, Matthew R.

2016-01-01

ABSTRACT There are an estimated 8 million users of smokeless tobacco products (STPs) in the United States, and yet limited data on microbial populations within these products exist. To better understand the potential microbiological risks associated with STP use, a study was conducted to provide a baseline microbiological profile of STPs. A total of 90 samples, representing 15 common STPs, were purchased in metropolitan areas in Little Rock, AR, and Washington, DC, in November 2012, March 2013, and July 2013. Bacterial populations were evaluated using culture, pyrosequencing, and denaturing gradient gel electrophoresis (DGGE). Moist-snuff products exhibited higher levels of bacteria (average of 1.05 × 106 CFU/g STP) and diversity of bacterial populations than snus (average of 8.33 × 101 CFU/g STP) and some chewing tobacco products (average of 2.54 × 105 CFU/g STP). The most common species identified by culturing were Bacillus pumilus, B. licheniformis, B. safensis, and B. subtilis, followed by members of the genera Oceanobacillus, Staphylococcus, and Tetragenococcus. Pyrosequencing analyses of the 16S rRNA genes identified the genera Tetragenococcus, Carnobacterium, Lactobacillus, Geobacillus, Bacillus, and Staphylococcus as the predominant taxa. Several species identified are of possible concern due to their potential to cause opportunistic infections and reported abilities to reduce nitrates to nitrites, which may be an important step in the formation of carcinogenic tobacco-specific N′-nitrosamines. This report provides a microbiological baseline to help fill knowledge gaps associated with microbiological risks of STPs and to inform potential regulations regarding manufacture and testing of STPs. IMPORTANCE It is estimated that there 8 million users of smokeless tobacco products (STPs) in the United States; however, there are limited data on microbial populations that exist within these products. The current study was undertaken to better understand the potential microbiological risks associated with STP use and provide a baseline microbiological profile of STPs. Several bacterial species were identified that are of possible concern due to their potential to cause opportunistic infections. In addition, some species have abilities to reduce nitrates to nitrites, which may be an important step in the formation of carcinogenic tobacco-specific N′-nitrosamines. Overall, this report provides a microbiological baseline to help fill knowledge gaps related to the microbiological risks of STPs and to inform potential regulations regarding the manufacture and testing of STPs. PMID:27565615

Clinical features, microbiology and surgical outcomes of infective endocarditis: a 13-year study from a UK tertiary cardiothoracic referral centre.

PubMed

Marks, D J B; Hyams, C; Koo, C Y; Pavlou, M; Robbins, J; Koo, C S; Rodger, G; Huggett, J F; Yap, J; Macrae, M B; Swanton, R H; Zumla, A I; Miller, R F

2015-03-01

Infective endocarditis (IE) causes substantial morbidity and mortality. Patient and pathogen profiles, as well as microbiological and operative strategies, continue to evolve. The impact of these changes requires evaluation to inform optimum management and identify individuals at high risk of early mortality. Identification of clinical and microbiological features, and surgical outcomes, among patients presenting to a UK tertiary cardiothoracic centre for surgical management of IE between 1998 and 2010. Retrospective observational cohort study. Clinical, biochemical, microbiological and echocardiographic data were identified from clinical records. Principal outcomes were all-cause 28-day mortality and duration of post-operative admission. Patients (n = 336) were predominantly male (75.0%); median age 52 years (IQR = 41-67). Most cases involved the aortic (56.0%) or mitral (53.9%) valves. Microbiological diagnoses, obtained in 288 (85.7%) patients, included streptococci (45.2%); staphylococci (34.5%); Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella (HACEK) organisms (3.0%); and fungi (1.8%); 11.3% had polymicrobial infection. Valve replacement in 308 (91.7%) patients included mechanical prostheses (69.8%), xenografts (24.0%) and homografts (6.2%). Early mortality was 12.2%, but fell progressively during the study (P = 0.02), as did median duration of post-operative admission (33.5 to 10.5 days; P = 0.0003). Multivariable analysis showed previous cardiothoracic surgery (OR = 3.85, P = 0.03), neutrophil count (OR = 2.27, P = 0.05), albumin (OR = 0.94, P = 0.04) and urea (OR = 2.63, P < 0.001) predicted early mortality. This study demonstrates reduced post-operative early mortality and duration of hospital admission for IE patients over the past 13 years. Biomarkers (previous cardiothoracic surgery, neutrophil count, albumin and urea), predictive of early post-operative mortality, require prospective evaluation to refine algorithms, further improve outcomes and reduce healthcare costs associated with IE. © The Author 2014. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Microbiological water methods: quality control measures for Federal Clean Water Act and Safe Drinking Water Act regulatory compliance.

PubMed

Root, Patsy; Hunt, Margo; Fjeld, Karla; Kundrat, Laurie

2014-01-01

Quality assurance (QA) and quality control (QC) data are required in order to have confidence in the results from analytical tests and the equipment used to produce those results. Some AOAC water methods include specific QA/QC procedures, frequencies, and acceptance criteria, but these are considered to be the minimum controls needed to perform a microbiological method successfully. Some regulatory programs, such as those at Code of Federal Regulations (CFR), Title 40, Part 136.7 for chemistry methods, require additional QA/QC measures beyond those listed in the method, which can also apply to microbiological methods. Essential QA/QC measures include sterility checks, reagent specificity and sensitivity checks, assessment of each analyst's capabilities, analysis of blind check samples, and evaluation of the presence of laboratory contamination and instrument calibration and checks. The details of these procedures, their performance frequency, and expected results are set out in this report as they apply to microbiological methods. The specific regulatory requirements of CFR Title 40 Part 136.7 for the Clean Water Act, the laboratory certification requirements of CFR Title 40 Part 141 for the Safe Drinking Water Act, and the International Organization for Standardization 17025 accreditation requirements under The NELAC Institute are also discussed.

Microbiological analysis of bile and its impact in critically ill patients with secondary sclerosing cholangitis.

PubMed

Voigtländer, Torsten; Leuchs, Ensieh; Vonberg, Ralf-Peter; Solbach, Philipp; Manns, Michael P; Suerbaum, Sebastian; Lankisch, Tim O

2015-05-01

Secondary sclerosing cholangitis in critically ill patients (SSC-CIP) is an emerging disease entity with unfavourable outcome. Our aim was to analyze the microbial spectrum in bile of patients with SSC-CIP and to evaluate the potential impact on the empiric antibiotic treatment in these patients. 169 patients (72 patients with SSC-CIP and 97 patients with primary sclerosing cholangitis (PSC)) were included in a prospective observational study between 2010 and 2013. Bile was obtained during endoscopic retrograde cholangiography (ERC) and microbiologically analyzed. Patients with SSC displayed a significantly different microbiological profile in bile. Enterococcus faecium, Pseudomonas aeruginosa and non-albicans species of Candida were more frequent in SSC compared to patients with PSC (p < 0.05). Patients with SSC showed a higher incidence of drug or multi-drug resistant organisms in bile (p = 0.001). The antimicrobial therapy was adjusted in 64% of patients due to resistance or presence of microorganisms not covered by the initial therapy regimen. Patients with SSC-CIP have a distinct microbial profile in bile. Difficult to treat organisms are frequent and an ERC with bile fluid collection for microbiological analysis should be considered in case of insufficient antimicrobial treatment. Copyright © 2015 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Evaluation of a Parchment Document, the 13th Century Incorporation Charter for the City of Krakow, Poland, for Microbial Hazards.

PubMed

Lech, Tomasz

2016-05-01

The literature of environmental microbiology broadly discusses issues associated with microbial hazards in archives, but these publications are mainly devoted to paper documents. There are few articles on historical parchment documents, which used to be very important for the development of literature and the art of writing. These studies present a broad spectrum of methods for the assessment of biodeterioration hazards of the parchment document in question. They are based on both conventional microbiological methods and advanced techniques of molecular biology. Here, a qualitative analysis was conducted, based on genetic identification of bacteria and fungi present on the document as well as denaturing gradient gel electrophoresis profiling and examining the destructive potential of isolated microbes. Moreover, the study involved a quantitative and qualitative microbiological assessment of the indoor air in the room where the parchment was kept. The microbes with the highest destructive potential that were isolated from the investigated item were Bacillus cereus and Acinetobacter lwoffii bacteria and Penicillium chrysogenum,Chaetomium globosum, and Trichoderma longibrachiatum fungi. The presence of the B. cereuss train was particularly interesting since, under appropriate conditions, it leads to complete parchment degradation within several days. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Chemical, Physicochemical, Nutritional, Microbiological, Sensory and Rehydration Characteristics of Instant Whole Beans (Phaseolus vulgaris)

PubMed Central

Ibarra-Zavala, Silvia Jazmin; Ramírez-Salas, Silvia Patricia; Rosas-Ulloa, Petra; Ramírez-Ramírez, José Carmen; Ulloa-Rangel, Blanca Estela

2015-01-01

Summary Instant whole beans obtained by drying at 25 °C were evaluated for their chemical, physicochemical, nutritional, microbiological, sensory and rehydration characteristics. The proximal composition of instant whole beans was typical of this kind of food, whereas aw and L*, a* and b* values were 0.639, 98.55, –0.28 and –1.52, respectively. In instant whole beans, 75% of the essential amino acids had a value greater or equal to the reference standard for adult humans; the protein quality in terms of chemical score was 95%. Microbiological counts of aerobic mesophilic bacteria, moulds, yeasts and total coliforms of rehydrated instant whole beans were <10 CFU/g, whereas the scores for colour, flavour, texture and overall acceptability were 7.22, 7.68, 7.24 and 7.34, respectively, on a 1–9 hedonic scale. The logarithmic and Pilosof models showed close fits (R2>0.99) to the experimental data for drying of cooked beans and rehydration of instant whole beans, respectively. In the light of the chemical, physicochemical, nutritional, microbiological, sensory and rehydration characteristics of instant whole beans found in this study, drying at 25 °C is recommended for the production of such food. PMID:27904331

Microbiology specimens obtained at the time of surgical lung biopsy for interstitial lung disease: clinical yield and cost analysis.

PubMed

Fibla, Juan J; Brunelli, Alessandro; Allen, Mark S; Wigle, Dennis; Shen, Robert; Nichols, Francis; Deschamps, Claude; Cassivi, Stephen D

2012-01-01

In efforts to obtain complete results, current practice in surgical lung biopsy (LB) for interstitial lung disease (ILD) recommends sending lung tissue samples for bacterial, mycobacterial, fungal, and viral cultures. This study assesses the value of this practice by evaluating the microbiology findings obtained from LB for ILD and their associated costs. A total of 296 consecutive patients (140 women, 156 men, median age=61 years) underwent LB for ILD from 2002 to 2009. All had lung tissue sent for microbiology examination. Microbiology results and resultant changes in patient management were analyzed retrospectively. A cost analysis was performed based upon nominal hospital charges adjusted on current inflation rates. Cost data included cultures, stains, smears, direct fluorescent antibody studies, and microbiologist consulting fees. As many as 25 patients (8.4%) underwent open LB and 271 (91.6%) underwent thoracoscopic LB. A total of 592 specimens were assessed (range 1-4 per patient). The most common pathologic diagnoses were idiopathic pulmonary fibrosis in 122 (41.2%), cryptogenic organizing pneumonia in 31 (10.5%), and respiratory bronchiolitis ILD in 16 (5.4%). Microbiology testing was negative in 174 patients (58.8%). A total of 118 of 122 (96.7%) positive results were clinically considered to be contaminants and resulted in no change in clinical management. The most common contaminants were Propionibacterium acnes (38 patients; 31%) and Penicillium fungus (16 patients; 13%). In only four patients (1.4%), the organism cultured (Nocardia one, Histoplasma one, and Aspergillus fumigatus two) resulted in a change in clinical management. The cost of microbiology studies per specimen was $984 (€709), with a total cost for the study cohort being $582,000 (€420,000). The yield and impact on clinical management of microbiology specimens from LB for ILD is very low. Its routine use in LB is questionable. We suggest it should be limited to those cases of ILD with a high suspicion of infection. Substantial cost savings are possible with this change in clinical practice.

Computer printing and filing of microbiology reports. 2. Evaluation and comparison with a manual system, and comparison of two manual systems.

PubMed Central

Goodwin, C S

1976-01-01

A manual system of microbiology reporting with a National Cash Register (NCR) form with printed names of bacteria and antiboitics required less time to compose reports than a previous manual system that involved rubber stamps and handwriting on plain report sheets. The NCR report cost 10-28 pence and, compared with a computer system, it had the advantages of simplicity and familarity, and reports were not delayed by machine breakdown, operator error, or data being incorrectly submitted. A computer reporting system for microbiology resulted in more accurate reports costing 17-97 pence each, faster and more accurate filing and recall of reports, and a greater range of analyses of reports that was valued particularly by the control-of-infection staff. Composition of computer-readable reports by technicians on Port-a-punch cards took longer than composing NCR reports. Enquiries for past results were more quickly answered from computer printouts of reports and a day book in alphabetical order. PMID:939810

Microbiology on Space Station Freedom

NASA Technical Reports Server (NTRS)

Pierson, Duane L. (Editor); Mcginnis, Michael R. (Editor); Mishra, S. K. (Editor); Wogan, Christine F. (Editor)

1991-01-01

This panel discussion convened in Houston, Texas, at the Lunar and Planetary Institute, on November 6 to 8, 1989, to review NASA's plans for microbiology on Space Station Freedom. A panel of distinguished scientists reviewed, validated, and recommended revisions to NASA's proposed acceptability standards for air, water, and internal surfaces on board Freedom. Also reviewed were the proposed microbiology capabilities and monitoring plan, disinfection procedures, waste management, and clinical issues. In the opinion of this advisory panel, ensuring the health of the Freedom's crews requires a strong goal-oriented research effort to determine the potential effects of microorganisms on the crewmembers and on the physical environment of the station. Because there are very few data addressing the fundamental question of how microgravity influences microbial function, the panel recommended establishing a ground-based microbial model of Freedom, with subsequent evaluation using in-flight shuttle data. Sampling techniques and standards will be affected by both technological advances in microgravity-compatible instrumentation, and by changes in the microbial population over the life of the station.

Brewing for Students: An Inquiry-Based Microbiology Lab †

PubMed Central

Sato, Brian K.; Alam, Usman; Dacanay, Samantha J.; Lee, Amanda K.; Shaffer, Justin F.

2015-01-01

In an effort to improve and assess student learning, there has been a push to increase the incorporation of discovery-driven modules and those that contain real-world relevance into laboratory curricula. To further this effort, we have developed, implemented, and assessed an undergraduate microbiology laboratory experiment that requires students to use the scientific method while brewing beer. The experiment allows students to brew their own beer and characterize it based on taste, alcohol content, calorie content, pH, and standard reference method. In addition, we assessed whether students were capable of achieving the module learning objectives through a pre-/posttest, student self-evaluation, exam-embedded questions, and an associated worksheet. These objectives included describing the role of the brewing ingredients and predicting how altering the ingredients would affect the characteristics of the beer, amongst others. By completing this experimental module, students accomplished the module objectives, had greater interest in brewing, and were more likely to view beer in scientific terms. Journal of Microbiology & Biology Education PMID:26753030

National collaborative shellfish pollution-indicator study: Site selection. Phase 2. Rept. for 1988-89

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

Leonard, D.L.; Slaughter, E.A.; Corning, B.C.

1990-07-01

Each year, about 16 million areas of estuarine waters are classified for the harvest of molluscan shellfish as open or limited to harvest according to microbiological 'indicator' standards and pollution survey guidelines established by the National Shellfish Sanitation Program. The program was developed in the 1920s in response to typhoid fever outbreaks associated with shellfish consumption. Current microbiological indicator standards in shellfish and shellfish-growing waters are extrpolated from standards set in the 1920s. Results from studies in the last decade have indicated that these microbiological indicator standards and thus classification of shellfish-growing waters may no longer be valid. The Nationalmore » Collaborative Shellfish Pollution Indicator Study is proposed as a four-year study to evaluate the current relationships between indicators of human enteric pathogens and the incidence of shellfish-borne diseases. Tasks forces were established to address specific issues, including site selection, shoreline surveys, and laboratory methodologies.« less

A Blended Learning Experience for Teaching Microbiology

PubMed Central

Sancho, Pilar; Corral, Ricardo; Rivas, Teresa; González, María Jesús; Chordi, Andrés

2006-01-01

Objectives To create a virtual laboratory system in which experimental science students could learn required skills and competencies while overcoming such challenges as time limitations, high cost of resources, and lack of feedback often encountered in a traditional laboratory setting. Design A blended learning experience that combines traditional practices and e-learning was implemented to teach microbiological methods to pharmacy students. Virtual laboratory modules were used to acquire nonmanual skills such as visual and mental skills for data reading, calculations, interpretation of the results, deployment of an analytical protocol, and reporting results. Assesment Learning achievement was evaluated by questions about microbiology case-based problems. Students' perceptions were obtained by assessment questionnaire. Conclusion By combining different learning scenarios, the acquisition of the necessary but otherwise unreachable competences was achieved. Students achieved similar grades in the modules whose initiation was in the virtual laboratory to the grades they achieved with the modules whose complete or partial initiation took place in the laboratory. The knowledge acquired was satisfactory and the participants valued the experience. PMID:17149449

Microbiological Quality of Panicum maximum Grass Silage with Addition of Lactobacillus sp. as Starter

NASA Astrophysics Data System (ADS)

Sumarsih, S.; Sulistiyanto, B.; Utama, C. S.

2018-02-01

The aim of the research was to evaluate microbiological quality of Panicum maximum grass silage with addition Lactobacillus sp as starter. The completely randomized design was been used on this research with 4 treaments and 3 replications. The treatments were P0 ( Panicum maximum grass silage without addition Lactobacillus sp ), P1 ( Panicum maximum grass silage with 2% addition Lactobacillus sp), P2 (Panicum maximum grass silage with 4% addition Lactobacillus sp) and P3 (Panicum maximum grass silage with 6% addition Lactobacillus sp).The parameters were microbial populations of Panicum maximum grass silage (total lactic acid bacteria, total bacteria, total fungi, and Coliform bacteria. The data obtained were analyzed variance (ANOVA) and further tests performed Duncan’s Multiple Areas. The population of lactic acid bacteria was higher (P<0.05) and the total bacteria, fungi and Coliform were lower (P<0.05) with addition Lactobacillus sp. Microbiological quality of Panicum maximum grass silage with addition Lactobacillus sp was better than no addition Lactobacillus sp.

Brewing for Students: An Inquiry-Based Microbiology Lab.

PubMed

Sato, Brian K; Alam, Usman; Dacanay, Samantha J; Lee, Amanda K; Shaffer, Justin F

2015-12-01

In an effort to improve and assess student learning, there has been a push to increase the incorporation of discovery-driven modules and those that contain real-world relevance into laboratory curricula. To further this effort, we have developed, implemented, and assessed an undergraduate microbiology laboratory experiment that requires students to use the scientific method while brewing beer. The experiment allows students to brew their own beer and characterize it based on taste, alcohol content, calorie content, pH, and standard reference method. In addition, we assessed whether students were capable of achieving the module learning objectives through a pre-/posttest, student self-evaluation, exam-embedded questions, and an associated worksheet. These objectives included describing the role of the brewing ingredients and predicting how altering the ingredients would affect the characteristics of the beer, amongst others. By completing this experimental module, students accomplished the module objectives, had greater interest in brewing, and were more likely to view beer in scientific terms. Journal of Microbiology & Biology Education.

Microbiological Safety of Kitchen Sponges Used in Food Establishments

PubMed Central

Bacha, Ketema

2016-01-01

Kitchen sponges are among the possible sources of contaminants in food establishments. The main purpose of the current study was, therefore, to assess the microbiological safety of sponges as it has been used in selected food establishments of Jimma town. Accordingly, the microbiological safety of a total of 201 kitchen sponges randomly collected from food establishments was evaluated against the total counts of aerobic mesophilic bacteria (AMB), Enterobacteriaceae, coliforms, and yeast and molds. The mean counts of aerobic mesophilic bacteria ranged from 7.43 to 12.44 log CFU/mm3. The isolated genera were dominated by Pseudomonas (16.9%), Bacillus (11.1%), Micrococcus (10.6%), Streptococcus (7.8%), and Lactobacillus (6%) excluding the unidentified Gram positive rods (4.9%) and Gram negative rods (9.9%). The high microbial counts (aerobic mesophilic bacteria, coliforms, Enterobacteriaceae, and yeast and molds) reveal the existence of poor kitchen sponge sanitization practice. Awareness creation training on basic hygienic practices to food handlers and periodic change of kitchen sponges are recommended. PMID:27840819

ALTERNATIVE DISINFECTANTS FOR DRINKING WATER TREATMENT

EPA Science Inventory

During a one-year study at Jefferson Parish, Louisiana the chemical, microbiological, and mutagenic effects of using the major drinking water disinfectants (chlorine, chlorine dioxide, chloramine, ozone) were evaluated. ests were performed on samples collected from various treatm...

ALTERNATIVE DISINFECTION FOR DRINKING WATER TREATMENT

EPA Science Inventory

During a one-yr study at Jefferson Parish, La., the chemical, microbiological, and mutagenic effects os using the major drinkgin water disinfectants (chlorine, chlorine dioxide, chloramine, ozone) were evaluated. Tests were performed on samples collected from various treatment s...

Multimedia Sampling During the Application of Biosolids on a Land Test Site

EPA Pesticide Factsheets

This project integrated research from several disciplines to evaluate the effects of land application of biosolids on air and volatile emissions and soil microbial characteristics. Measurements included chemical, physical, and microbiological analytes.

[Isolation of anaerobes during a 30-month observation at a hospital microbiology laboratory].

PubMed

Pistono, P G; Rapetti, I; Stacchini, E; Vironda, N; D'Usi, M P; Guasco, C

1989-01-01

The authors evaluate retrospectively the results obtained from the research of anaerobial bacteria on 1313 samples received at the Microbiology Laboratory of the "Ospedale Civile di Ivrea" over a period of 31 months (6/1/86-12/31/88). From this evaluation, high percentages of detection of anaerobic bacteria are emerging in the following infections: appendiculare abscesses (60%), intestinal operations (71%), wounds (57%), tubovarian abscesses (100%), as well as thoracic empyema (50%). Also relevant are the isolations from skin and subcutaneous tissues: breast infections (50%) preputial infections (60%), perineal and perirectal abscesses (60%). The incident of anaerobic bacteria in bacteriemia is 17%. The most representative anaerobic bacteria group are: Bacteroides spp. (56%), Peptostreptococcus spp. (12%), Propionibacterium spp. (9%), Fusobacterium spp. (7%) Clostridium spp. (6%), Veillonella spp. and Eubacterium spp. (3%). In the intraabdominal infections prevails the Bacteroides group, particularly fragilis species, while in the skin and subcutaneous infections prevails the Peptostreptococcus group.

The chemotaxis-like Che1 pathway has an indirect role in adhesive cell properties of Azospirillum brasilense.

PubMed

Siuti, Piro; Green, Calvin; Edwards, Amanda Nicole; Doktycz, Mitchel J; Alexandre, Gladys

2011-10-01

The Azospirillum brasilense chemotaxis-like Che1 signal transduction pathway was recently shown to modulate changes in adhesive cell surface properties that, in turn, affect cell-to-cell aggregation and flocculation behaviors rather than flagellar-mediated chemotaxis. Attachment to surfaces and root colonization may be functions related to flocculation. Here, the conditions under which A. brasilense wild-type Sp7 and che1 mutant strains attach to abiotic and biotic surfaces were examined using in vitro attachment and biofilm assays combined with atomic force microscopy and confocal microscopy. The nitrogen source available for growth is found to be a major modulator of surface attachment by A. brasilense and could be promoted in vitro by lectins, suggesting that it depends on interaction with surface-exposed residues within the extracellular matrix of cells. However, Che1-dependent signaling is shown to contribute indirectly to surface attachment, indicating that distinct mechanisms are likely underlying flocculation and attachment to surfaces in A. brasilense. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Enhanced drug transport through alginate biofilms using magnetic nanoparticles

NASA Astrophysics Data System (ADS)

McGill, Shayna L.; Cuylear, Carla; Adolphi, Natalie L.; Osinski, Marek; Smyth, Hugh

2009-02-01

The development of microbiological biofilms greatly reduces the efficacy of antibiotic therapies and is a serious problem in chronic infection and for implantable medical devices. We investigated the potential of superparamagnetic nanoparticles to increase transport through in vitro models of alginate biofilms. An in vitro alginate biofilm model was developed to mimic the composition of in vivo samples of P. aeruginosa infections. Transport through this model biofilm was performed using both bulk diffusion methods and single particle tracking techniques in the presence and absence of an external magnetic field. Bulk diffusion of nanoparticles through the biofilm was significantly enhanced in the presence of a magnetic field, both visually and quantitatively. Nanoparticle trajectories also showed transport increases were significantly higher when magnetic fields were applied. We also showed that surface chemistry (cationic, anioni, or neutral) of the nanoparticles significantly influenced transport rates. Finally, nanoparticle size also influenced the transport rates and variability of transport rates through the biofilm. In these first studies using magnetic nanoparticles in bacterial biofilms, we demonstrate that transport enhancement can be achieved and further studies are warranted.

In vitro detection and quantification of botulinum neurotoxin type E activity in avian blood

USGS Publications Warehouse

Piazza, T.M.; Blehert, D.S.; Dunning, F.M.; Berlowski-Zier, B. M.; Zeytin, F.N.; Samuel, M.D.; Tucker, W.C.

2011-01-01

Botulinum neurotoxin serotype E (BoNT/E) outbreaks in the Great Lakes region cause large annual avian mortality events, with an estimated 17,000 bird deaths reported in 2007 alone. During an outbreak investigation, blood collected from bird carcasses is tested for the presence of BoNT/E using the mouse lethality assay. While sensitive, this method is labor-intensive and low throughput and can take up to 7 days to complete. We developed a rapid and sensitive in vitro assay, the BoTest Matrix E assay, that combines immunoprecipitation with high-affinity endopeptidase activity detection by F??rster resonance energy transfer (FRET) to rapidly quantify BoNT/E activity in avian blood with detection limits comparable to those of the mouse lethality assay. On the basis of the analysis of archived blood samples (n = 87) collected from bird carcasses during avian mortality investigations, BoTest Matrix E detected picomolar quantities of BoNT/E following a 2-h incubation and femtomolar quantities of BoNT/E following extended incubation (24 h) with 100% diagnostic specificity and 91% diagnostic sensitivity. ?? 2011, American Society for Microbiology.

Intestinal colonization by enteroaggregative Escherichia coli supports long-term bacteriophage replication in mice.

PubMed

Maura, Damien; Morello, Eric; du Merle, Laurence; Bomme, Perrine; Le Bouguénec, Chantal; Debarbieux, Laurent

2012-08-01

Bacteriophages have been known to be present in the gut for many years, but studies of relationships between these viruses and their hosts in the intestine are still in their infancy. We isolated three bacteriophages specific for an enteroaggregative O104:H4 Escherichia coli (EAEC) strain responsible for diarrhoeal diseases in humans. We studied the replication of these bacteriophages in vitro and in vivo in a mouse model of gut colonization. Each bacteriophage was able to replicate in vitro in both aerobic and anaerobic conditions. Each bacteriophage individually reduced biofilms formed on plastic pegs and a cocktail of the three bacteriophages was found to be more efficient. The cocktail was also able to infect bacterial aggregates formed on the surface of epithelial cells. In the mouse intestine, bacteriophages replicated for at least 3 weeks, provided the host was present, with no change in host levels in the faeces. This model of stable and continuous viral replication provides opportunities for studying the long-term coevolution of virulent bacteriophages with their hosts within a mammalian polymicrobial ecosystem. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Formation of In Vitro Mixed-Species Biofilms by Lactobacillus pentosus and Yeasts Isolated from Spanish-Style Green Table Olive Fermentations.

PubMed

León-Romero, Ángela; Domínguez-Manzano, Jesús; Garrido-Fernández, Antonio; Arroyo-López, Francisco Noé; Jiménez-Díaz, Rufino

2016-01-15

The present work details the in vitro interactions between Lactobacillus pentosus and yeast strains isolated from table olive processing to form mixed biofilms. Among the different pairs assayed, the strongest biofilms were obtained from L. pentosus and Candida boidinii strain cocultures. However, biofilm formation was inhibited in the presence of d-(+)-mannose. In addition, biofilm formation by C. boidinii monoculture was stimulated in the absence of cell-cell contact with L. pentosus. Scanning electron microscopy revealed that a sort of "sticky" material formed by the yeasts contributed to substrate adherence. Hence, the data obtained in this work suggest that yeast-lactobacilli biofilms may be favored by the presence of a specific mate of yeast and L. pentosus, and that more than one mechanism might be implicated in the biofilm formation. This knowledge will help in the design of appropriate mixed starter cultures of L. pentosus-yeast species pairs that are able to improve the quality and safety of Spanish-style green table olive processing. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

In vitro algicidal effect of guanidine on Prototheca zopfii genotype 2 strains isolated from clinical and subclinical bovine mastitis.

PubMed

Alves, A C; Capra, E; Morandi, S; Cremonesi, P; Pantoja, J C F; Langoni, H; de Vargas, A P C; da Costa, M M; Jagielski, T; Bolaños, C A D; Guerra, S T; Ribeiro, M G

2017-06-01

Prototheca species have increasingly been reported to be opportunistic pathogens that cause mastitis in dairy herds, and it poses an emergent problem because at present, there are no effective therapies for the treatment of protothecal mastitis. This study investigated the in vitro algicidal effect of guanidine on 75 Prototheca zopfii genotype 2 strains isolated from 75 cases of clinical and subclinical bovine mastitis. All strains were susceptible to guanidine in vitro with minimal algaecide concentrations ranging from 0·001 to 0·035%. Guanidine is known to have a high microbicidal effect and is considered to be a new generation microbicidal compound. It is not toxic to human mucous membranes and conjunctivas at low concentrations and has been used as a disinfectant in swimming pools and as an antiseptic for human wounds. The algicidal action of guanidine at low concentrations indicates that it could be an alternative disinfectant or antiseptic for cleaning of the dairy environment and milking equipment, in pre- and postdipping solutions, in the chemical dry therapy of bovine teats and even in the intramammary therapy of P. zopfii infections. This is the first report of the in vitro algicidal effect of guanidine on P. zopfii strains of animal origin. Prototheca zopfii genotype 2 is an opportunistic pathogen of bovine mastitis. To date, no effective therapies against protothecal mastitis have been developed. The in vitro algicidal effect of guanidine on 75 P. zopfii genotype 2 strains isolated from cows revealed that all of the isolates were susceptible to the compound at low concentrations, which indicates that guanidine may be used as an antiseptic/disinfectant for dairy milking equipment, in pre- and postdipping solutions, and as a chemical dry therapy or an intramammary therapy. This study describes the in vitro algicidal effect of guanidine on P. zopfii for the first time. © 2017 The Society for Applied Microbiology.

Management of Chronic Periodontitis Using Subgingival Irrigation of Ozonized Water: A Clinical and Microbiological Study.

PubMed

Issac, Annie V; Mathew, Jayan Jacob; Ambooken, Majo; Kachappilly, Arun Jose; Pk, Ajithkumar; Johny, Thomas; Vk, Linith; Samuel, Anju

2015-08-01

Adjunctive use of professional subgingival irrigation with scaling and root planing (SRP) has been found to be beneficial in eradicating the residual microorganisms in the pocket. To evaluate the effect of ozonized water subgingival irrigation on microbiologic parameters and clinical parameters namely Gingival index, probing pocket depth, and clinical attachment level. Thirty chronic periodontitis patients with probing pocket depth ≥6mm on at least one tooth on contra lateral sides of opposite arches were included in the study. The test sites were subjected to ozonized water subgingival irrigation with subgingival irrigation device fitted with a modified subgingival tip. Control sites were subjected to scaling and root planing only. The following clinical parameters were recorded initially and after 4 weeks at the test sites and control sites. Plaque Index, Gingival Index, probing pocket depth, clinical attachment level. Microbiologic sampling was done for the test at the baseline, after scaling, immediately after ozonized water subgingival irrigation and after 4 weeks. In control sites microbiologic sampling was done at the baseline, after scaling and after 4 weeks. The following observations were made after 4 weeks. The results were statistically analysed using independent t-test and paired t-test. Test sites showed a greater reduction in pocket depth and gain in clinical attachment compared to control sites. The total anaerobic counts were significantly reduced by ozonized water subgingival irrigation along with SRP compared to SRP alone. Ozonized water subgingival irrigation can improve the clinical and microbiological parameters in patients with chronic periodontitis when used as an adjunct to scaling and root planing.

Microbiological quality and bacterial diversity of the tropical oyster Crassostrea rhizophorae in a monitored farming system and from natural stocks.

PubMed

Silva Neta, M T; Maciel, B M; Lopes, A T S; Marques, E L S; Rezende, R P; Boehs, G

2015-12-02

Microbiological evaluation is one of the most important parameters for analyzing the viability of an oyster farming system, which addresses public health and ecological concerns. Here, the microbiological quality of the oyster Crassostrea rhizophorae cultivated in a monitored environment and from natural beds in Bahia, northeastern Brazil, was determined. Bacterial diversity in oysters was measured by polymerase chain reaction-denaturing gradient gel electrophoresis. Sequence analysis revealed that most bacterial species showed similarity with uncultured or unidentified bacteria from environmental samples, and were clustered into the phylum Proteobacteria. Diverse bacteria from cultivated (monitored) oyster samples were grouped in the same cluster with a high similarity index (above 79%). Microbiological analyses revealed that these oysters did not contain pathogens. These results reflect the natural balance of the microbial communities essential to the maintenance of health and in inhibiting pathogen colonization in the oyster. On the other hand, bacterial diversity of samples from native stocks in extractive areas displayed a similarity index varying between 55 and 77%, and all samples were clustered separately from each other and from the cluster of samples derived from the cultivation area. Microbiological analyses showed that oysters from the extractive area were not fit for human consumption. This reflected a different composition of the microbial community in this area, probably resulting from anthropic impact. Our study also demonstrated that low temperatures and high rainfall limits the bacterial concentration in tropical oysters. This is the first study analyzing the total bacterial community profiles of the oyster C. rhizophorae.

Biological control of anthracnose (Colletotrichum gloeosporioides) in yam by Streptomyces sp.MJM5763.

PubMed

Palaniyandi, S A; Yang, S H; Cheng, J H; Meng, L; Suh, J-W

2011-08-01

To find a suitable biocontrol agent for yam anthracnose caused by Colletotrichum gloeosporioides. An actinobacterial strain, MJM5763, showing strong antifungal activity, multiple biocontrol and plant growth-promoting traits was isolated from a yam cultivation field in Yeoju, South Korea. Based on morphological and physiological characteristics and analysis of the 16S rDNA sequence, strain MJM5763 was identified as a novel strain of Streptomyces and was designated as Streptomyces sp. MJM5763. Treatment with MJM5763 and the crude culture filtrate extract (CCFE) was effective in suppressing anthracnose in detached yam leaves in vitro and reduced incidence and severity of anthracnose in yam plants under greenhouse conditions. The CCFE treatment was the most effective of all the treatments and reduced the anthracnose severity by 85-88% and the incidence by 79-81%, 90 days after inoculation with the pathogen. CCFE treatment was also effective under field conditions and showed a reduction of 86 and 75% of anthracnose severity and incidence, respectively. Streptomyces sp. strain MJM5763 was effective in biocontrolling anthracnose in yam caused by C. gloeosporioides. Streptomyces sp. MJM5763 is a potential alternative to chemical fungicides for reducing yield losses to anthracnose in yam. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

In vitro study on the effect of doxycycline on the microbial activity of soil determined by redox-potential measuring system.

PubMed

Szakmár, Katalin; Reichart, Olivér; Szatmári, István; Erdősi, Orsolya; Szili, Zsuzsanna; László, Noémi; Székely Körmöczy, Péter; Laczay, Péter

2014-09-01

The potential effect of doxycycline on the microbial activity was investigated in three types of soil. Soil samples were spiked with doxycycline, incubated at 25°C and tested at 0, 2, 4 and 6 days after treatment. The microbiological activity of the soil was characterized by the viable count determined by plate pouring and by the time necessary to reach a defined rate of the redox-potential decrease termed as time to detection (TTD).The viable count of the samples was not changed during the storage. The TTD values, however exhibited a significant increase in the 0.2-1.6 mg/kg doxycycline concentration range compared to the untreated samples indicating concentration-dependent inhibitory effect on microbial activity. The potency of the effect was different in the 3 soil types. To describe the combined effect of the doxycycline concentration and time on the biological activity of one type of soil a mathematical model was constructed and applied.The change of microbial metabolic rate could be measured also without (detectable) change of microbial count when the traditional microbiological methods are not applicable. The applied new redox potential measurement-based method is a simple and useful procedure for the examination of microbial activity of soil and its potential inhibition by antibiotics.

Microbiological Horticultural Internship Final Abstract

NASA Technical Reports Server (NTRS)

Palmer, Shane R.; Spencer, Lashelle (Editor)

2017-01-01

GMO dwarf plum (Prunus domestica) is being evaluated as a candidate food crop for long duration space flight missions. A project was undertaken to develop a protocol for transferring selected genetic lines of GMO plum (previously maintained in pots and propagated by cuttings at NASA's Kennedy Space Center in Florida) into in vitro tissue culture. In vitro culture may reduce the space, materials, and labor required to maintain the current lines of GMO plum and better preserve them for future study. Fresh plant material from three selected GMO plum lines (NASA-5, NASA-10, and NASA-11) and a non-modified control line (Control-5) were processed aseptically into in vitro culture on four separate occasions. The impact of multiple treatments on the successful growth of GMO plum tissue in vitro were tested: Parent explant tissue type (leaf petioles, stem nodes containing buds and internodes without buds), tissue sterilization method [soaking in 10 bleach only (5 min for petioles or 10 min for nodesinternodes), or soaking in 70 EtOH (30 sec) followed by 10 bleach (5 min for petioles and 10 min for nodesinternodes)], and media type [three Murashige and Skoog-based medias (SGM, SRM, and SRM+2,4-D) and one recipe containing woody plant media (WPM)]. 22.2 of the plates containing tissue sterilized with bleach alone developed microbial contamination after two weeks, while only 11.8 of plates containing tissue sterilized sequentially with EtOH and bleach developed contamination. Node bud tissue from all four genetic lines of plum produced leafy plantlets on SGM and SRM media after 4-6 weeks. The most numerous and well-developed plantlets were present on SGM. Upon reaching suitable size, plantlets were transferred to larger media containers for further growth. Some node bud growth occurred on SRM+2,4-D and WPM 2.5 weeks after plating, however as of yet no pieces on SRM+2,4-D have adequate development for transferring. Tissue pieces from NASA-5 plated on WPM are developing leaves and will be ready for transferring soon. Petioles and internode tissue lacking bud meristem failed to produce any plantlets on any plates, however petioles developed large masses of undifferentiated callus tissue on SRM+2,4-D media. These callused pieces were then transferred to SRM+TDZ media, which resulted in even larger callus growth but no differentiation. All four selected plum lines were successfully transitioned into in vitro culture. Nodes from NASA-5 and NASA-10 lines produced the most numerous and well-developed leafy plantlets in vitro, while those from NASA-11 and Control-5 were generally smaller, slower growing and less numerous. The best method overall was to use young stem node tissue with buds, surface sterilize the pieces sequentially with 70 EtOH and 10 bleach, and then plate them onto SGM media. Future areas of study will include introducing additional genetic lines of GMO plum into in vitro culture, attempting to induce shoot growth in petiole callus tissue, testing methods (such as cold storage) that extend the time interval between transferring explants into new media, and testing viability of plantlets transferred from in vitro culture back to traditional pot culture.

Effect of an oxygenating agent on oral bacteria in vitro and on dental plaque composition in healthy young adults

PubMed Central

Fernandez y Mostajo, Mercedes; van der Reijden, Wil A.; Buijs, Mark J.; Beertsen, Wouter; van der Weijden, Fridus; Crielaard, Wim; Zaura, Egija

2014-01-01

Oral bacteria live in symbiosis with the host. Therefore, when mouthwashes are indicated, selective inhibition of taxa contributing to disease is preferred instead of broad-spectrum antimicrobials. The potential selectivity of an oxygenating mouthwash, Ardox-X® (AX), has not been assessed. The aim of this study was to determine the antimicrobial potential of AX and the effects of a twice-daily oral rinse on dental plaque composition. Material and methods: In vitro, 16 oral bacterial strains were tested using agar diffusion susceptibility, minimum inhibitory and minimum bactericidal concentration tests. A pilot clinical study was performed with 25 healthy volunteers. Clinical assessments and microbiological sampling of supragingival plaque were performed at 1 month before the experiment (Pre-exp), at the start of the experiment (Baseline) and after the one-week experimental period (Post-exp). During the experiment individuals used AX mouthwash twice daily in absence of other oral hygiene measures. The microbiological composition of plaque was assessed by 16S rRNA gene amplicon sequencing. Results: AX showed high inter-species variation in microbial growth inhibition. The tested Prevotella strains and Fusobacterium nucleatum showed the highest sensitivity, while streptococci and Lactobacillus acidophilus were most resistant to AX. Plaque scores at Pre-exp and Baseline visits did not differ significantly (p = 0.193), nor did the microbial composition of plaque. During a period of 7-days non-brushing but twice daily rinsing plaque scores increased from 2.21 (0.31) at Baseline to 2.43 (0.39) Post-exp. A significant microbial shift in composition was observed: genus Streptococcus and Veillonella increased while Corynebacterium, Haemophilus, Leptotrichia, Cardiobacterium and Capnocytophaga decreased (p ≤ 0.001). Conclusion: AX has the potential for selective inhibition of oral bacteria. The shift in oral microbiome after 1 week of rinsing deserves further research. PMID:25101249

A single-centre 10-year experience with Candida bloodstream infections

PubMed Central

Labbé, Annie-Claude; Pépin, Jacques; Patiño, Carlos; Castonguay, Stéphanie; Restieri, Christiane; Laverdiere, Michel

2009-01-01

OBJECTIVE: To describe the clinical and microbiological features associated with Candida bloodstream infections observed at Hôpital Maisonneuve-Rosemont (Montreal, Quebec) between August 1996 and July 2006. METHODS: Episodes were retrieved from the microbiology laboratory. Different patient episodes and different isolate episodes in the same patient were selected. Antifungal susceptibility was determined by the Clinical and Laboratory Standards Institute’s (USA) M27A2 method. RESULTS: A total of 190 different episodes of candidemia in 185 patients were identified. Eleven (6%) episodes occurred in outpatients. Candida albicans was identified in the majority of episodes (57%). Its frequency remained stable over the years. The proportion of Candida krusei candidemia episodes increased between 2003 and 2006, but this was not statistically significant. A central venous indwelling catheter or a peripherally inserted central catheter line was present in the majority of patients (167 [88%]). Of the indwelling catheters removed at the time of diagnosis, 39% were positive for Candida species on culture. Overall, voriconazole was the most active agent (the minimum inhibitory concentration required to inhibit the growth of 90% of organisms was 0.5 mg/L). Resistance to fluconazole was observed in 26 (14%) isolates (C albicans, 4%; versus non-albicans Candida species, 27%; P<0.001). Being on the hematology-oncology unit at the time of diagnosis (adjusted OR 7.8; 95% CI 2.3 to 27.1; P=0.001) and having received fluconazole or itraconazole within the past three months (adjusted OR 8.3; 95% CI 2.8 to 24.4; P<0.001) were significantly associated with resistance to fluconazole in multivariate analysis. CONCLUSIONS: At Hôpital Maisonneuve-Rosemont, the frequency and species distribution of blood isolates of Candida remained stable over the past decade. In vitro resistance of C albicans to fluconazole and itraconazole remained minimal; resistance of non-albicans Candida species to fluconazole did not increase significantly. The new antifungal agents all had high in vitro activity against the bloodstream Candida isolates. PMID:20514159

Non-animal approaches for toxicokinetics in risk evaluations of food chemicals.

PubMed

Punt, Ans; Peijnenburg, Ad A C M; Hoogenboom, Ron L A P; Bouwmeester, Hans

2017-01-01

The objective of the present work was to review the availability and predictive value of non-animal toxicokinetic approaches and to evaluate their current use in European risk evaluations of food contaminants, additives and food contact materials, as well as pesticides and medicines. Results revealed little use of quantitative animal or human kinetic data in risk evaluations of food chemicals, compared with pesticides and medicines. Risk evaluations of medicines provided sufficient in vivo kinetic data from different species to evaluate the predictive value of animal kinetic data for humans. These data showed a relatively poor correlation between the in vivo bioavailability in rats and dogs versus that in humans. In contrast, in vitro (human) kinetic data have been demonstrated to provide adequate predictions of the fate of compounds in humans, using appropriate in vitro-in vivo scalers and by integration of in vitro kinetic data with in silico kinetic modelling. Even though in vitro kinetic data were found to be occasionally included within risk evaluations of food chemicals, particularly results from Caco-2 absorption experiments and in vitro data on gut-microbial conversions, only minor use of in vitro methods for metabolism and quantitative in vitro-in vivo extrapolation methods was identified. Yet, such quantitative predictions are essential in the development of alternatives to animal testing as well as to increase human relevance of toxicological risk evaluations. Future research should aim at further improving and validating quantitative alternative methods for kinetics, thereby increasing regulatory acceptance of non-animal kinetic data.

[The opportunities, challenges and trends in the rejuvenation of microbiology].

PubMed

Shen, Ping; Chen, Xiangdong

2010-01-01

In history, the development of microbiology had undergone two golden ages and some depression time as well. In the last two decades, the application of many physiochemical technologies including genomics, structural biology, bioinformatics, PCR, and high-resolution microscopy has led to a series of breakthroughs in microbiology. Microbiology has now awakened and entered its third golden age for development. This review discusses our view of the opportunities, challenges, and trends in the current advancement of microbiology. The topics include: (1) The two golden ages for microbiology in history. (2) The opportunities and challenges in the rejuvenation of microbiology. (3) The characteristics and trends of the current development of microbiology. (4) Integral microbiology--the hallmark of the third golden age.

Evaluation of Natural Compounds for Antimicrobial Activity in the Introductory Microbiology Laboratory.

ERIC Educational Resources Information Center

Finer, Kim R.

1997-01-01

Presents an experiment that provides students with an opportunity to investigate folk medicine and herbal cures and their accompanying claims. Involves isolating some active compounds from plant materials and demonstrating their antibacterial activity. (JRH)

Ceftobiprole: a review of a broad-spectrum and anti-MRSA cephalosporin.

PubMed

Zhanel, George G; Lam, Ashley; Schweizer, Frank; Thomson, Kristjan; Walkty, Andrew; Rubinstein, Ethan; Gin, Alfred S; Hoban, Daryl J; Noreddin, Ayman M; Karlowsky, James A

2008-01-01

Ceftobiprole, an investigational cephalosporin, is currently in phase III clinical development. Ceftobiprole is a broad-spectrum cephalosporin with demonstrated in vitro activity against Gram-positive cocci, including meticillin-resistant Staphylococcus aureus (MRSA) and meticillin-resistant S. epidermidis, penicillin-resistant S. pneumoniae, Enterococcus faecalis, Gram-negative bacilli including AmpC-producing Escherichia coli and Pseudomonas aeruginosa, but excluding extended-spectrum beta-lactamase-producing strains. Like cefotaxime, ceftriaxone, ceftazidime, and cefepime, ceftobiprole demonstrates limited activity against anaerobes such as Bacteroides fragilis and non-fragilis Bacteroides spp. In single-step and serial passage in vitro resistance development studies, ceftobiprole demonstrated a low propensity to select for resistant subpopulations. Ceftobiprole, like cefepime, is a weak inducer and a poor substrate for AmpC beta-lactamases.Ceftobiprole medocaril, the prodrug of ceftobiprole, is converted by plasma esterases to ceftobiprole in <30 minutes. Peak serum concentrations of ceftobiprole observed at the end of a single 30-minute infusion were 35.5 mug/mL for a 500-mg dose and 59.6 mug/mL for a 750-mg dose. The volume of distribution of ceftobiprole is 0.26 L/kg ( approximately 18 L), protein binding is 16%, and its serum half-life is approximately 3.5 hours. Ceftobiprole is renally excreted ( approximately 70% in the active form) and systemic clearance correlates with creatinine clearance, meaning that dosage adjustment is required in patients with renal dysfunction. Ceftobiprole has a modest post-antibiotic effect (PAE) of approximately 0.5 hours for MRSA and a longer PAE of approximately 2 hours for penicillin-resistant pneumococci. Ceftobiprole, when administered intravenously at 500 mg once every 8 hours (2-hour infusion), has a >90% probability of achieving f T(>MIC) (free drug concentration exceeds the minimum inhibitory concentration [MIC]) for 40% and 60%, respectively, of the dosing interval for isolates with ceftobiprole MIC < or =4 and < or =2 mg/L, respectively.Currently, only limited clinical trial data are published for ceftobiprole. In a phase III trial, 784 patients with Gram-positive skin infections were randomized to treatment with either ceftobiprole 500 mg or vancomycin 1 g, each administered twice daily for 7-14 days; 93.3% of patients were clinically cured with ceftobiprole compared with 93.5% receiving vancomycin, and the eradication rate for MRSA infections was 91.8% for ceftobiprole compared with 90% for vancomycin. A phase III, randomized, double-blind, multicenter trial compared ceftobiprole 500 mg every 8 hours with vancomycin 1 g every 12 hours plus ceftazidime 1 g every 8 hours in patients with complicated skin and skin structure infections. Of the 828 patients enrolled, 31% had diabetic foot infections, 30% had abscesses, and 22% had wounds. No difference in clinical cure was reported in the clinically evaluable, intent-to-treat and microbiologically evaluable populations with cure rates of 90.5%, 81.9%, and 90.8%, respectively, in the ceftobiprole-treated patients and 90.2%, 80.8%, and 90.5%, respectively, in the vancomycin plus ceftazidime-treated group. Microbiologic eradication of Gram-positive cocci meticillin-susceptible S. aureus (MSSA) [ceftobiprole 91% vs vancomycin plus ceftazidime 92%] and MRSA (ceftobiprole 87% vs vancomycin plus ceftazidime 80%), as well as Gram-negative bacilli, E. coli (ceftobiprole 89% vs vancomycin plus ceftazidime 92%), and P. aeruginosa (ceftobiprole 87% vs vancomycin plus ceftazidime 100%), was not significantly different between groups. Similar cures rates in the microbiologically evaluable population occurred in both groups for Panton-Valentine leukocidin (PVL)-positive MSSA and PVL-positive MRSA.Currently, ceftobiprole has completed phase III trials for complicated skin and skin structure infections due to MRSA and nosocomial pneumonia due to suspected or proven MRSA; phase III trials are also ongoing in community-acquired pneumonia. Ceftobiprole has so far demonstrated a good safety profile in preliminary studies with similar tolerability to comparators. The broad-spectrum activity of ceftobiprole may allow it to be used as monotherapy in situations where a combination of antibacterials might be required. Further clinical studies are needed to determine the efficacy and safety of ceftobiprole and to define its role in patient care.

Trypanosoma brucei (UMP synthase null mutants) are avirulent in mice, but recover virulence upon prolonged culture in vitro while retaining pyrimidine auxotrophy.

PubMed

Ong, Han B; Sienkiewicz, Natasha; Wyllie, Susan; Patterson, Stephen; Fairlamb, Alan H

2013-10-01

African trypanosomes are capable of both de novo synthesis and salvage of pyrimidines. The last two steps in de novo synthesis are catalysed by UMP synthase (UMPS) - a bifunctional enzyme comprising orotate phosphoribosyl transferase (OPRT) and orotidine monophosphate decarboxylase (OMPDC). To investigate the essentiality of pyrimidine biosynthesis in Trypanosoma brucei, we generated a umps double knockout (DKO) line by gene replacement. The DKO was unable to grow in pyrimidine-depleted medium in vitro, unless supplemented with uracil, uridine, deoxyuridine or UMP. DKO parasites were completely resistant to 5-fluoroorotate and hypersensitive to 5-fluorouracil, consistent with loss of UMPS, but remained sensitive to pyrazofurin indicating that, unlike mammalian cells, the primary target of pyrazofurin is not OMPDC. The null mutant was unable to infect mice indicating that salvage of host pyrimidines is insufficient to support growth. However, following prolonged culture in vitro, parasites regained virulence in mice despite retaining pyrimidine auxotrophy. Unlike the wild-type, both pyrimidine auxotrophs secreted substantial quantities of orotate, significantly higher in the virulent DKO line. We propose that this may be responsible for the recovery of virulence in mice, due to host metabolism converting orotate to uridine, thereby bypassing the loss of UMPS in the parasite. © 2013 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.

In Vitro Emergence of High Persistence upon Periodic Aminoglycoside Challenge in the ESKAPE Pathogens.

PubMed

Michiels, Joran Elie; Van den Bergh, Bram; Verstraeten, Natalie; Fauvart, Maarten; Michiels, Jan

2016-08-01

Health care-associated infections present a major threat to modern medical care. Six worrisome nosocomial pathogens-Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.-are collectively referred to as the "ESKAPE bugs." They are notorious for extensive multidrug resistance, yet persistence, or the phenotypic tolerance displayed by a variant subpopulation, remains underappreciated in these pathogens. Importantly, persistence can prevent eradication of antibiotic-sensitive bacterial populations and is thought to act as a catalyst for the development of genetic resistance. Concentration- and time-dependent aminoglycoside killing experiments were used to investigate persistence in the ESKAPE pathogens. Additionally, a recently developed method for the experimental evolution of persistence was employed to investigate adaptation to high-dose, extended-interval aminoglycoside therapy in vitro We show that ESKAPE pathogens exhibit biphasic killing kinetics, indicative of persister formation. In vitro cycling between aminoglycoside killing and persister cell regrowth, evocative of clinical high-dose extended-interval therapy, caused a 37- to 213-fold increase in persistence without the emergence of resistance. Increased persistence also manifested in biofilms and provided cross-tolerance to different clinically important antibiotics. Together, our results highlight a possible drawback of intermittent, high-dose antibiotic therapy and suggest that clinical diagnostics might benefit from taking into account persistence. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Effects of Lactobacillus formosensis S215T and Lactobacillus buchneri on quality and in vitro ruminal biological activity of condensed tannins in sweet potato vines silage.

PubMed

Mangwe, M C; Rangubhet, K T; Mlambo, V; Yu, B; Chiang, H I

2016-11-01

This study investigated the influence of two microbial inoculants; Lactobacillus formosensis and Lactobacillus buchneri on fermentation quality, chemical composition, aerobic stability and in vitro ruminal biological activity of condensed tannins in sweet potato vines silage. Sweet potato vines were ensiled for 28 and 60 days; without inoculant (CON), with Lact. buchneri (LB) or with Lact. formosensis (LF), both inoculants applied to achieve 1 × 10 6  CFU g -1 fresh forage. Lactobacillus formosensis silage had lower pH and higher lactic acid than all treatments. Yeasts and moulds were not detected in LB silage after ensiling. Lactobacillus buchneri silage was more aerobically stable than all treatments, whereas LF was more stable than CON silage. In vitro ruminal biological activity of condensed tannins was lower in microbial-inoculated silages than CON after ensiling. Lactobacillus formosensis improved fermentability by reducing silage pH and improved aerobic stability by producing more propionate, which inhibited yeast activity. Lactobacillus buchneri improved aerobic stability of the silage by producing more acetate. Both strains effectively reduced the antinutritional effect of condensed tannins after ensiling. Lactobacillus formosensis has the potential to be used as a silage inoculant because of its ability to improve fermentability and aerobic stability in sweet potato vines silage. © 2016 The Society for Applied Microbiology.

Genomic variant representation in a Chlamydia population is dynamic and adaptive with dependence on in vitro and in vivo passage.

PubMed

Jasper, Deana K; Sigar, Ira M; Schripsema, Justin H; Sainvil, Carlyn K; Smith, Christopher L; Yeruva, Laxmi; Rank, Roger G; Murthy, Ashlesh K; Widder, Jared R; Ramsey, Kyle H

2015-02-01

We have previously shown that Chlamydia muridarum has multiple genomic variants that concomitantly vary in their in vitro and in vivo phenotype. Herein, we used real-time polymerase chain reaction-based genotyping assays to query plaque-cloned isolates of C. muridarum for the frequency of eight selected polymorphisms. These strains had no history of passage in vivo since their original isolation from laboratory mice. There was significant variance in the frequency of two of the eight polymorphisms assessed with the remaining exhibiting a low rate of variance. To determine if any of these polymorphisms were more favorable for in vivo conditions, we blindly passaged non-clonal C. muridarum three times at 7-day intervals through the urogenital tract of mice. Seven of the eight polymorphisms varied in frequency following in vivo passage and four of these varied between C. muridarum strains. Selected isolates displayed variable growth rates and cytopathic effect in vitro. We conclude that multiple genotypic variants are present within the existing known C. muridarum strains and that the frequency of these variants changes upon introduction into the mouse host. These findings lend support to the concept that genotypic proportional representation in a chlamydial population is dynamic and adaptive. © The Author 2015. Published by Oxford University Press on behalf of on behalf of Federation of European Microbiological Society.

Effects on crops of irrigation with treated municipal wastewaters.

PubMed

Fasciolo, G E; Meca, M I; Gabriel, E; Morábito, J

2002-01-01

The fertilizing potential of treated municipal wastewater (oxidation ditch) and crop sanitary acceptability for direct human consumption were evaluated in Mendoza, Argentina. Two experiments were performed on a pilot plot planted with garlic (1998) and onions (1999) using furrow irrigation with three types of water in 10 random blocks: treated effluent (2.5 x 10(3) MPN Escherichia coli/100 ml, 3 helminth eggs/l, and Salmonella (positive); and well water (free of microorganisms), with and without fertilizer. Two responses were evaluated: (1) crop yield, and (2) crop microbiological quality for human consumption at different times after harvest. Crop yields were compared using Variance analysis. Crops' sanitary acceptability was assessed using a two-class sampling program for Salmonella (n=10; c=0), and a three-class program for E. coli (n=5, c=2, M=10(3) and m=10 MPN/g) as proposed by the International Commission on Microbiological Specifications for Foods (ICMSF) for fresh vegetables. Wastewater irrigation acted as well water with fertilizer, increasing garlic and onion yields by 10% and 15%, respectively, compared to irrigation with well water with no fertilizer. Wastewater-irrigated garlic reached sanitary acceptability 90 days after harvest, once attached roots and soil were removed. Onions, which were cleaned immediately after harvest, met this qualification earlier than garlic (55 days). Neither the wastewater-irrigated crops nor the control crops were microbiologically acceptable for consumption raw at harvest.

Vestiges of Submarine Serpentinization Recorded in the Microbiology of Continental Ophiolite Complexes

NASA Astrophysics Data System (ADS)

Schrenk, M. O.; Sabuda, M.; Brazelton, W. J.; Twing, K. I.

2017-12-01

The study of serpentinization-influenced microbial ecosystems at and below the seafloor has accelerated in recent years with multidisciplinary drilling expeditions to the Atlantis Massif (X357), Southwest Indian Ridge (X360) and Mariana Forearc (X366). In parallel, a number of studies have surveyed serpentinizing systems in ophiolite complexes which host a range of geologic histories, geochemical characteristics, fluid pathways, and consequently microbiology. As ophiolite complexes originate as seafloor materials, it is likely that a microbiological record of seafloor serpentinization processes is maintained through the emplacement and weathering of continental serpentinites. This hypothesis was evaluated through a global comparison of continental serpentinite springs and groundwater, ranging from highly brackish (saline) to freshwater. One of the most saline sites, known as the Coast Range Ophiolite Microbial Observatory (CROMO), was used as a point-of-comparison to marine serpentinizing systems, such as the Lost City Hydrothermal Field. Although there was little taxonomic overlap between microbial populations in marine and terrestrial systems, both communities harbored an abundance of genes involved in sulfur metabolism, including sulfide oxidation, thiosulfate disproportionation, and sulfate reduction. The phylogeny of key genes involved in these metabolic processes was evaluated relative to published studies and compared between sites. Together, these data provide insights into both the functioning of microbial communities in modern-day serpentinizing systems, and the transport processes that disperse microorganisms between marine and terrestrial serpentinites.

[Husk of Venezuelan cocoa as raw material of infusions].

PubMed

Sangronis, Elba; José Soto, María; Valero, Yolmar; Buscema, Ignacio

2014-06-01

In the cocoa bean industry, some by-products go underutilized. Some of these components could provide other innovative products, and such is the case with the husk of the cocoa bean. Previous studies have attributed the husk with a high antioxidant capacity, which added to its relative low cost, makes it an attractive ingredient for the production of infusions. However, prior to promoting it as such, its quality needs to be guaranteed. This study evaluated the chemical composition of the husk of cocoa, its microbiologic quality and other parameters in order to be considered raw material in the preparation of infusions. The cocoa was cultivated in two different states in Venezuela. Moisture, protein, fat, ash, carbohydrates, microbiologic quality and ochratoxin A as well antioxidant properties, content of foreign matter, insoluble ash in HCL and aqueous extract were evaluated in the husk of cocoa seeds. Applied methods were in compliance with national and international norms. Significant differences were determined between the samples through the ANOVA application. A low level in moisture content, but high in ash, along with a microbiologic quality that met the norm, and an absence of ochratoxin A were observed in the totality of the analyzed samples. Low levels of foreign matter, the high value of its aqueous extract and high phenolic compounds content with antioxidant activity allow for the recommendation of the husk of cocoa as raw material for the preparation of infusions.

Characterization of the geology, geochemistry, hydrology and microbiology of the in-situ air stripping demonstration site at the Savannah River Site

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

Eddy, C.A.; Looney, B.B.; Dougherty, J.M.

1991-05-01

The Savannah River Site is the location of an Integrated Demonstration Project designed to evaluate innovative remediation technologies for environmental restoration at sites contaminated with volatile organic contaminants. This demonstration utilizes directionally drilled horizontal wells to deliver gases and extract contaminants from the subsurface. Phase I of the Integrated Demonstration focused on the application and development of in-situ air stripping technologies to remediate soils and sediments above and below the water table as well as groundwater contaminated with volatile organic contaminants. The objective of this report is to provide baseline information on the geology, geochemistry, hydrology, and microbiology of themore » demonstration site prior to the test. The distribution of contaminants in soils and sediments in the saturated zone and groundwater is emphasized. These data will be combined with data collected after the demonstration in order to evaluate the effectiveness of in-situ air stripping. New technologies for environmental characterization that were evaluated include depth discrete groundwater sampling (HydroPunch) and three-dimensional modeling of contaminant data.« less

Development of a pentaplex PCR assay for the simultaneous detection of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, L. delbrueckii subsp. lactis, L. helveticus, L. fermentum in whey starter for Grana Padano cheese.

PubMed

Cremonesi, Paola; Vanoni, Laura; Morandi, Stefano; Silvetti, Tiziana; Castiglioni, Bianca; Brasca, Milena

2011-03-30

A pentaplex PCR assay for the rapid, selective and simultaneous detection of Lactobacillus helveticus, L. delbrueckii subsp. lactis, L. delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and L. fermentum, was developed. The target sequences were a group of genes coding for beta-galactosidase production (S. thermophilus and L. delbrueckii subsp. bulgaricus), for cell-enveloped associated proteinase synthesis (L. helveticus), for dipeptide transport system production (L. delbrueckii subsp. lactis) and for arginine-ornithine antiporter protein production (L. fermentum). The analytical specificity of the assay was evaluated with 5 reference strains and 140 lactic acid bacterial strains derived from raw milk cheeses and belonging to the Lactobacillus, Streptococcus, Lactococcus and Enterococcus genera. The identification limit for each target strain was 10(3)CFU/ml. This new molecular assay was used to investigate the LAB population by direct extraction of DNA from the 12 whey cultures for Grana Padano. The pentaplex PCR assay revealed a good correspondence with microbiological analyses and allowed to identify even minor LAB community members which, can be out-competed in vitro by numerically more abundant microbial species. Copyright © 2011 Elsevier B.V. All rights reserved.

The addition of inulin and Lactobacillus casei 01 in sheep milk ice cream.

PubMed

Balthazar, Celso F; Silva, Hugo L A; Esmerino, Erick A; Rocha, Ramon S; Moraes, Jeremias; Carmo, Mariana A V; Azevedo, Luciana; Camps, Ihosvany; K D Abud, Yuri; Sant'Anna, Celso; Franco, Robson M; Freitas, Mônica Q; Silva, Marcia C; Raices, Renata S L; Escher, Graziela B; Granato, Daniel; Senaka Ranadheera, C; Nazarro, Filomena; Cruz, Adriano G

2018-04-25

The effect of the Lactobacillus casei 01 and inulin addition on sheep milk ice cream during storage (-18 °C, 150 days) was investigated. Control, probiotic and synbiotic ice cream (10% w/w sheep milk cream; 10% w/w sheep milk cream, L. casei 01, 6 log CFU/mL; 10% w/w inulin, L. casei 01, 6 log CFU/mL, respectively) were manufactured. Microbiological counts (probiotic count, survival after in vitro gastrointestinal resistance, Caco-2 cell adhesion), bioactivity and microstructure were analysed. Physical and textural characteristics, colour parameters, thermal analysis and organic acids/volatile compounds were also evaluated. All formulations supported L. casei 01 viability and maintained above the minimum therapeutic level (>6 log CFU/mL) during storage. Inulin did not affect L. casei 01 survival after the passage through simulated gastrointestinal tract and adhesion to Caco-2 cells while improved the ACE-inhibitory and antioxidant activity. L. casei 01 addition produced several volatile compounds, such as carboxylic acids, alcohols, aldehydes and ketones. Also, scanning electron microscopy showed an interaction between probiotic bacteria and inulin fibre on synbiotic ice cream and the adhesion of L. casei to Caco-2 cells was observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Relationship Between the Remaining Dentin Thickness and Coronal Pulp Status of Decayed Primary Molars.

PubMed

Berbari, Roula; Fayyad-Kazan, Hussein; Ezzedine, Mohamad; Fayyad-Kazan, Mohammad; Bandon, Daniel; Sfeir, Elia

2017-01-01

The aim of this study was to assess the correlation between the remaining dentin thickness (RDT) in deep decayed primary molars and the inflammatory status and bacterial composition of the corresponding coronal pulp. We hypothesized that RDT could be used as a reference for clinicians in assigning the indication for pulpotomy. Pulpotomies were conducted on the cameral pulp of 48 primary molars. Microorganisms, such as Lactobacillus sp., Streptococcus sp., and Prevotella sp., were identified and quantified and levels of tumor necrosis factor-alpha (TNF-α) and interlukin-6 (IL-6) were assessed. The correlation between the pre-operative RDT based on radiographic images and inflammatory-microbial profiles in vitro was evaluated using Spearman's rho correlation coefficient. All data analysis was performed using a statistical software program (SPSS 20.0, SPSS Inc., Chicago, IL, USA). Immunological and microbiological studies revealed elevated levels of TNF-α and IL-6 cytokines, and Lactobacillus sp., Streptococcus sp. and Prevotella sp. in the cameral pulp with an RDT measuring up to 1.1 mm. No significant relationship could be established between RDT, inflammatory status and microbial content of the pulps. The RDT remains a key clinical factor that needs to be assessed when establishing the indication for pulpotomy. Additional parameters that can improve this therapy should be investigated in the future.

Impact of plant growth-promoting rhizobacteria on root colonization potential and life cycle of Rhizophagus irregularis following co-entrapment into alginate beads.

PubMed

Loján, P; Demortier, M; Velivelli, S L S; Pfeiffer, S; Suárez, J P; de Vos, P; Prestwich, B D; Sessitsch, A; Declerck, S

2017-02-01

This study aimed at evaluating the impact of seven plant growth-promoting rhizobacteria (PGPR) on root colonization and life cycle of Rhizophagus irregularis MUCL 41833 when co-entrapped in alginate beads. Two in vitro experiments were conducted. The first consisted of the immobilization of R. irregularis and seven PGPR isolates into alginate beads to assess the effect of the bacteria on the pre-symbiotic growth of the fungus. In the second experiment, the best performing PGPR from experiment 1 was tested for its ability to promote the symbiotic development of the AMF in potato plantlets from three cultivars. Results showed that only one isolate identified as Pseudomonas plecoglossicida (R-67094) promoted germ tube elongation and hyphal branching of germinated spores during the pre-symbiotic phase of the fungus. This PGPR further promoted the symbiotic development of the AMF in potato plants. The co-entrapment of Ps. plecoglossicida R-67094 and R. irregularis MUCL 41833 in alginate beads improved root colonization by the AMF and its further life cycle under the experimental conditions. Co-entrapment of suitable AMF-PGPR combinations within alginate beads may represent an innovative technology that can be fine-tuned for the development of efficient consortia-based bioformulations. © 2016 The Society for Applied Microbiology.

Molecular mechanism of plasma sterilization in solution with the reduced pH method: importance of permeation of HOO radicals into the cell membrane

NASA Astrophysics Data System (ADS)

Takai, Eisuke; Ikawa, Satoshi; Kitano, Katsuhisa; Kuwabara, Junpei; Shiraki, Kentaro

2013-07-01

Sterilization of certain infected areas of the human body surface is necessary for dental and surgical therapies. Because the blood is filled with body fluid, sterilization in solution is essential. In vitro solution sterilization has been successively carried out using a combination of low-temperature atmospheric-pressure plasma and the reduced pH method, where the solution is sufficiently acidic. Here, we show the molecular mechanism of such plasma sterilization in solution based on microbiology. Three kinds of bacteria were inactivated by plasma treatment under various pH conditions. The theoretical and experimental models revealed that the sterilization was characterized by the concentration of hydroperoxy radicals (HOO·), which were dependent on the pH value. Bacterial inactivation rates were proportional to the HOO· concentrations calculated by the theoretical model. To evaluate the penetration of radicals into the cell membrane, a bacterial model using dye-included micelles was used. Decolouration rates of the model were also in proportion with the calculated HOO· concentrations. These results indicate that the key species for plasma sterilization were hydroperoxy radicals. More importantly, the high permeation of hydroperoxy radicals into the cell membrane plays a key role for efficient bactericidal inactivation using the reduced pH method.

Infectious disease risks in xenotransplantation.

PubMed

Fishman, Jay A

2018-03-07

Hurdles exist to clinical xenotransplantation including potential infectious transmission from nonhuman species to xenograft recipients. In anticipation of clinical trials of xenotransplantation, the associated infectious risks have been investigated. Swine and immunocompromised humans share some potential pathogens. Swine herpesviruses including porcine cytomegalovirus (PCMV) and porcine lymphotropic herpesvirus (PLHV) are largely species-specific and do not, generally, infect human cells. Human cellular receptors exist for porcine endogenous retrovirus (PERV), which infects certain human-derived cell lines in vitro. PERV-inactivated pigs have been produced recently. Human infection due to PERV has not been described. A screening paradigm can be applied to exclude potential human pathogens from "designated pathogen free" breeding colonies. Various microbiological assays have been developed for screening and diagnosis including antibody-based tests and qualitative and quantitative molecular assays for viruses. Additional assays may be required to diagnose pig-specific organisms in human xenograft recipients. Significant progress has been made in the evaluation of the potential infectious risks of clinical xenotransplantation. Infectious risk would be amplified by intensive immunosuppression. The available data suggest that risks of xenotransplant-associated recipient infection are manageable and that clinical trials can be performed safely. Possible infectious risks of xenotransplantation to the community at large are undefined but merit consideration. © 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.

Safety, potential biotechnological and probiotic properties of bacteriocinogenic Enterococcus lactis strains isolated from raw shrimps.

PubMed

Ben Braïek, Olfa; Morandi, Stefano; Cremonesi, Paola; Smaoui, Slim; Hani, Khaled; Ghrairi, Taoufik

2018-04-01

The aims of this study are to isolate new bacteriocinogenic lactic acid bacterial strains from white (Penaeus vannamei) and pink (Palaemon serratus) raw shrimps and evaluate their technological and probiotic potentialities. Seven strains were selected, among fifty active isolates, as producing interesting antimicrobial activity. Identified as Enterococcus lactis, these isolates were able to produce enterocins A, B and/or P. The safety aspect, assessed by microbiological and molecular tests, demonstrated that the strains were susceptible to relevant antibiotics such as vancomycin, negative for haemolysin and gelatinase activities, and did not harbour virulence and antibiotic resistance genes. The assessment of potential probiotic and technological properties showed a low or no lipolytic activity, moderate milk-acidifying ability, high reducing power, proteolytic activity and tolerance to bile (P < 0.05) and good autoaggregation and coaggregation capacities. Two strains designated as CQ and C43 exhibiting high enzymatic activities and bile salt hydrolase activity were found to display high survival under simulated in vitro oral cavity and gastrointestinal tract conditions caused by presence of lysozyme, pepsin, pancreatin, bile salts and acidic pH. This study highlights safe Enterococcus lactis strains with great technological and probiotic potentials for future application as new starter, adjunct, protective or probiotic cultures in food industry. Copyright © 2018 Elsevier Ltd. All rights reserved.

Disinfection capacity of PuriLens contact lens cleaning unit against Acanthamoeba.

PubMed

Hwang, Thomas S; Hyon, Joon Young; Song, Jae Kyung; Reviglio, Victor E; Spahr, Harry T; O'Brien, Terrence P

2004-01-01

The PuriLens contact lens system is indicated for cleaning and disinfection of soft (hydrophilic) contact lenses by means of subsonic agitation to remove lens deposits and microorganisms, and ultraviolet irradiation of the storage solution for disinfection. The capacity of the PuriLens system to disinfect storage solutions contaminated with known concentrations of Staphylococcus aureus, Pseudomonas aeruginosa, and Acanthamoeba species was evaluated. An in vitro assessment of the antibacterial and antiparasitic efficacy of the PuriLens system was performed. Separated batches of the storage solution for the cleansing system were contaminated with stock strains of S. aureus and P. aeruginosa. A comparison of the microbiologic content was made between the solution before and after the cycle. The PuriLens system effectively eradicated S. aureus and P. aeruginosa organisms after a 15-minute cycle. However, viable cysts of acanthamoeba were recovered in the solution after the 15-minute cycle. The PuriLens system is highly efficient in protecting against contamination with common bacterial ocular pathogens. Acanthamoeba cysts, however, can survive in the solution or contact lens bath undergoing integrated subsonic debridement and indirect ultraviolet light disinfection. Use of chemical disinfecting solutions that contain agents such as chlorhexidine or other cationic antiseptics may be advisable in conjunction with use of the PuriLens device, especially in high-risk settings.

Isolation and screening of proangiogenic and antiangiogenic metabolites producing rare actinobacteria from soil.

PubMed

Azarakhsh, Y; Mohammadipanah, F; Nassiri, S M; Siavashi, V; Hamedi, J

2017-06-01

Angiogenesis is a physiological process that has important impacts on the pathology and healing of various diseases, and its induction or inhibition by bioactive actinobacterial metabolites can help the treatment of some diseases. In this study, the effects of actinobacterial extract in the process of angiogenesis have been explored. In this research, proangiogenic and antiangiogenic metabolites producing actinobacteria were isolated from soil samples and their fermentation broth were extracted and after evaluation of their toxicity by MTT assay, antiangiogenic and proangiogenic activities were screened against human umbilical vein endothelial cells (HUVECs) by in vitro tube formation and migration assay. Isolated strains were identified through molecular techniques. The results showed that Nocardiopsis arvandica UTMC 103 and Nonomuraea sp. UTMC 2180 extracts had a high potential of anti-angiogenic activity on HUVECs. For the first time proangiogenic potency of a rare actinobacterium, Kribbella sp. UTMC 522, was reported, and N. arvandica UTMC 103 and Nonomuraea sp. UTMC 2180 extracts inhibits the proliferation, migration and angiogenesis activity of HUVECs with reasonable potency. Metabolites of the introduced rare actinobacteria are potent proangiogenic and angiogenic inhibitors. Identification of angiogenic-antiangiogenic mechanisms and purification of the extracts would be useful in therapeutic angiogenesis. © 2017 The Society for Applied Microbiology.

21 CFR 866.2540 - Microbiological incubator.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Microbiological incubator. 866.2540 Section 866.2540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2540 Microbiological...

21 CFR 866.2540 - Microbiological incubator.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Microbiological incubator. 866.2540 Section 866.2540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2540 Microbiological...

21 CFR 866.2540 - Microbiological incubator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Microbiological incubator. 866.2540 Section 866.2540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2540 Microbiological...

21 CFR 866.2540 - Microbiological incubator.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Microbiological incubator. 866.2540 Section 866.2540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2540 Microbiological...

21 CFR 866.2540 - Microbiological incubator.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Microbiological incubator. 866.2540 Section 866.2540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2540 Microbiological...

STANDARDIZATION AND VALIDATION OF MICROBIOLOGICAL METHODS FOR EXAMINATION OF BIOSOLIDS

EPA Science Inventory

The objective of this presentation is to discuss pathogens of concern in biosolids, the analytical techniques used to evaluate microorganisms in biosolids, and to discuss standardization and validation of analytical protocols for microbes within a complex matrix. Implications of ...

A Quick-Test for Biochar Effects on Seed Germination

EPA Science Inventory

Biochar is being globally evaluated as a soil amendment to improve soil characteristics (e.g. soil water holding, nutrient exchange, microbiology, pesticides and chemical availability) to increase crop yields. Unfortunately, there are no quick tests to determine what biochar type...

MICROBIOLOGICAL RISK ASSESSMENT FOR LAND APPLICATION OF MUNICIPAL SLUDGE

EPA Science Inventory

Each major option for the disposal/reuse of municipal sludges poses potential risks to human health or the environment because of the microbial contaminants in sludge. Therefore, risk assessment methodology appropriate for pathogen risk evaluation for land application and distrib...

Mechanical vs. manual cleaning of hospital beds: a prospective intervention study.

PubMed

Hopman, J; Nillesen, M; de Both, E; Witte, J; Teerenstra, S; Hulscher, M; Voss, A

2015-06-01

Cleaning regimens for hospital beds were evaluated in the context of a rising prevalence of highly resistant micro-organisms and increasing financial pressure on healthcare systems. Dutch hospitals have to choose between standardized, mechanical bed-washers advised in national guidance and manual cleaning. To evaluate the quality of mechanical and manual bed-cleaning regimens. The multi-faceted analysis of bed-cleaning regimens consisted of three steps. In Step 1, the training of the domestic service team was evaluated. In Step 2, the cleaning quality of manual and mechanical regimens was assessed. Soiled beds, obtained at random, from different departments were evaluated using microbiological analysis (N = 40) and ATP (N = 20). ATP and microbiological contamination were measured in five predetermined locations on all beds. In Step 3, manual cleaning was introduced over a two-month pilot study at the surgical short-stay unit, and beds from other departments were processed according to the 'gold standard' mechanical cleaning. ATP levels were evaluated in three locations on 300 beds after cleaning. Training was found to improve the quality of cleaning significantly. Mechanical cleaning resulted in significantly lower ATP levels than manual cleaning. Mechanical cleaning shows less variation and results in consistently lower ATP levels than manual cleaning. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Efficacy of anti-retraction devices in preventing bacterial contamination of dental unit water lines.

PubMed

Berlutti, Francesca; Testarelli, Luca; Vaia, Francesco; De Luca, Massimo; Dolci, Giovanni

2003-02-01

In this study we examine the efficacy of anti-retraction devices in preventing microbial contamination of dental unit water lines (DUWLs). The study was performed on 54 randomly selected DUs in use at private and public institutions for over six months. The selected DUs were all currently commercially available. To evaluate the efficiency of anti-retraction devices, two different methods were employed, mechanical and microbiological. The ADA/ANSI specification #47 (corresponding to a water retraction of less than 40.3 microl) was used for the evaluation of the retraction determined using the mechanical method; the presence/absence of test microorganisms in DUWLs upstream the turbine after the test was used for evaluating the microbiological assay. Both evaluation methods indicated correct amounts of retraction and prevention of DUWL contamination occurred in only two cases (3.7%). Correct retraction was noted in six other dental units (DUs), but their DUWLs became contaminated during testing. Six other produced the opposite results-improper retraction, yet no contamination. The remaining 40 DUs (74.0%) failed both evaluations. The results showed that the overwhelming majority of the anti-retraction devices did not prevent retraction when the turbine stopped running, leading to a contamination of the water lines, and to a consequent possible cross-contamination of the patients.

The CTFA Evaluation of Alternatives Program: an evaluation of in vitro alternatives to the Draize primary eye irritation test. (Phase III) surfactant-based formulations.

PubMed

Gettings, S D; Lordo, R A; Hintze, K L; Bagley, D M; Casterton, P L; Chudkowski, M; Curren, R D; Demetrulias, J L; Dipasquale, L C; Earl, L K; Feder, P I; Galli, C L; Glaza, S M; Gordon, V C; Janus, J; Kurtz, P J; Marenus, K D; Moral, J; Pape, W J; Renskers, K J; Rheins, L A; Roddy, M T; Rozen, M G; Tedeschi, J P; Zyracki, J

1996-01-01

The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data.

An Azole-Tolerant Endosomal Trafficking Mutant of Candida albicans Is Susceptible to Azole Treatment in a Mouse Model of Vaginal Candidiasis.

PubMed

Peters, Brian M; Luna-Tapia, Arturo; Tournu, Hélène; Rybak, Jeffrey M; Rogers, P David; Palmer, Glen E

2017-06-01

We recently reported that a Candida albicans endosomal trafficking mutant continues to grow after treatment with the azole antifungals. Herein, we report that the vps21 Δ/Δ mutant does not have a survival advantage over wild-type isolates after fluconazole treatment in a mouse model of vaginal candidiasis. Furthermore, loss of VPS21 does not synergize with established mechanisms of azole resistance, such as overexpression of efflux pumps or of Erg11p, the target enzyme of the azoles. In summary, although loss of VPS21 function enhances C. albicans survival after azole treatment in vitro , it does not seem to affect azole susceptibility in vivo . Copyright © 2017 American Society for Microbiology.

Integrated structural biology and molecular ecology of N-cycling enzymes from ammonia-oxidizing archaea.

PubMed

Tolar, Bradley B; Herrmann, Jonathan; Bargar, John R; van den Bedem, Henry; Wakatsuki, Soichi; Francis, Christopher A

2017-10-01

Knowledge of the molecular ecology and environmental determinants of ammonia-oxidizing organisms is critical to understanding and predicting the global nitrogen (N) and carbon cycles, but an incomplete biochemical picture hinders in vitro studies of N-cycling enzymes. Although an integrative structural and dynamic characterization at the atomic scale would advance our understanding of function tremendously, structural knowledge of key N-cycling enzymes from ecologically relevant ammonia oxidizers is unfortunately extremely limited. Here, we discuss the challenges and opportunities for examining the ecology of ammonia-oxidizing organisms, particularly uncultivated Thaumarchaeota, through (meta)genome-driven structural biology of the enzymes ammonia monooxygenase (AMO) and nitrite reductase (NirK). © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

The Recombinant Bacteriophage Endolysin HY-133 Exhibits In Vitro Activity against Different African Clonal Lineages of the Staphylococcus aureus Complex, Including Staphylococcus schweitzeri.

PubMed

Idelevich, Evgeny A; Schaumburg, Frieder; Knaack, Dennis; Scherzinger, Anna S; Mutter, Wolfgang; Peters, Georg; Peschel, Andreas; Becker, Karsten

2016-04-01

HY-133 is a recombinant bacteriophage endolysin with bactericidal activity againstStaphylococcus aureus Here, HY-133 showedin vitroactivity against major African methicillin-susceptible and methicillin-resistantS. aureuslineages and ceftaroline/ceftobiprole- and borderline oxacillin-resistant isolates. HY-133 was also active againstStaphylococcus schweitzeri, a recently described species of theS. aureuscomplex. The activity of HY-133 on the tested isolates (MIC50, 0.25 μg/ml; MIC90, 0.5 μg/ml; range, 0.125 to 0.5 μg/ml) was independent of the species and strain background or antibiotic resistance. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Presence of quinolone resistance to qnrB1 genes and blaOXA-48 carbapenemase in clinical isolates of Klebsiella pneumoniae in Spain.

PubMed

Rodríguez Martínez, J M; Díaz-de Alba, P; Lopez-Cerero; Ruiz-Carrascoso, G; Gomez-Gil, R; Pascual, A

2014-01-01

A study is presented on the presence of quinolone resistance qnrB1 genes in clinical isolates belonging to the largest series of infections caused by OXA-48-producing Klebsiella pneumoniae in a single-centre outbreak in Spain. Evidence is also provided, according to in vitro results, that there is a possibility of co-transfer of plasmid harbouring blaOXA-48 with an other plasmid harbouring qnrB1 in presence of low antibiotic concentrations of fluoroquinolones, showing the risk of multi-resistance screening. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Does RecA have a role in Borrelia recurrentis?

PubMed

Cutler, S J; Rinky, I J; Bonilla, E M

2011-02-01

Genomic sequencing of two relapsing fever spirochaetes showed truncation of recA in Borrelia recurrentis, but not in Borrelia duttonii. RecA has an important role among bacteria; we investigated whether this characteristic was representative of B. recurrentis, or an artefact following in vitro cultivation. We sequenced recA directly from samples of patient with louse-borne relapsing fever (B. recurrentis) or tick-borne relapsing fever (B. duttonii). We confirmed the premature stop codon in seven louse-borne relapsing fever samples, and its absence from three tick-borne relapsing fever samples. Furthermore, specific signature polymorphisms were found that could differentiate between these highly similar spirochaetes. © 2010 The Authors. Journal Compilation © 2010 European Society of Clinical Microbiology and Infectious Diseases.

In Vitro Cross-Resistance Profiles of Rilpivirine, Dapivirine, and MIV-150, Nonnucleoside Reverse Transcriptase Inhibitor Microbicides in Clinical Development for the Prevention of HIV-1 Infection.

PubMed

Giacobbi, Nicholas S; Sluis-Cremer, Nicolas

2017-07-01

Rilpivirine (RPV), dapivirine (DPV), and MIV-150 are in development as microbicides. It is not known whether they will block infection of circulating nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistant human immunodeficiency virus type 1 (HIV-1) variants. Here, we demonstrate that the activity of DPV and MIV-150 is compromised by many resistant viruses containing single or double substitutions. High DPV genital tract concentrations from DPV ring use may block replication of resistant viruses. However, MIV-150 genital tract concentrations may be insufficient to inhibit many resistant viruses, including those harboring K103N or Y181C. Copyright © 2017 American Society for Microbiology.

Microbiological sampling of spacecraft cabling, antennas, solar panels and thermal blankets

NASA Technical Reports Server (NTRS)

Koukol, R. C.

1973-01-01

Sampling procedures and techniques described resulted from various flight project microbiological monitoring programs of unmanned planetary spacecraft. Concurrent with development of these procedures, compatibility evaluations were effected with the cognizant spacecraft subsystem engineers to assure that degradation factors would not be induced during the monitoring program. Of significance were those areas of the spacecraft configuration for which special handling precautions and/or nonstandard sample gathering techniques were evolved. These spacecraft component areas were: cabling, high gain antenna, solar panels, and thermal blankets. The compilation of these techniques provides a historical reference for both the qualification and quantification of sampling parameters as applied to the Mariner Spacecraft of the late 1960's and early 1970's.

Otitis Media and Nasopharyngeal Colonization in ccl3-/- Mice.

PubMed

Deniffel, Dominik; Nuyen, Brian; Pak, Kwang; Suzukawa, Keigo; Hung, Jun; Kurabi, Arwa; Wasserman, Stephen I; Ryan, Allen F

2017-11-01

We previously found CC chemokine ligand 3 (CCL3) to be a potent effector of inflammation during otitis media (OM): exogenous CCL3 rescues the OM phenotype of tumor necrosis factor-deficient mice and the function of macrophages deficient in several innate immune molecules. To further delineate the role of CCL3 in OM, we evaluated middle ear (ME) responses of ccl3 -/- mice to nontypeable Haemophilus influenzae (NTHi). CCL chemokine gene expression was evaluated in wild-type (WT) mice during the complete course of acute OM. OM was induced in ccl3 -/- and WT mice, and infection and inflammation were monitored for 21 days. Phagocytosis and killing of NTHi by macrophages were evaluated by an in vitro assay. The nasopharyngeal bacterial load was assessed in naive animals of both strains. Many CCL genes showed increased expression levels during acute OM, with CCL3 being the most upregulated, at levels 600-fold higher than the baseline. ccl3 -/- deletion compromised ME bacterial clearance and prolonged mucosal hyperplasia. ME recruitment of leukocytes was delayed but persisted far longer than in WT mice. These events were linked to a decrease in the macrophage capacity for NTHi phagocytosis and increased nasopharyngeal bacterial loads in ccl3 -/- mice. The generalized impairment in inflammatory cell recruitment was associated with compensatory changes in the expression profiles of CCL2, CCL7, and CCL12. CCL3 plays a significant role in the clearance of infection and resolution of inflammation and contributes to mucosal host defense of the nasopharyngeal niche, a reservoir for ME and upper respiratory infections. Therapies based on CCL3 could prove useful in treating or preventing persistent disease. Copyright © 2017 American Society for Microbiology.

Microbiological evaluation of different strategies for management of snakes in captivity.

PubMed

Campagner, M V; Bosco, S M G; Bagagli, E; Cunha, M L R S; Jeronimo, B C; Saad, E; Biscola, N P; Ferreira, R S; Barraviera, B

2012-01-01

Keeping snakes in captivity to produce venom for scientific research and production of inputs is now a worldwide practice. Maintaining snakes in captivity involves capture, infrastructure investments, management techniques, and appropriate qualified personnel. Further, the success of the project requires knowledge of habitat, nutrition, and reproduction, and control of opportunistic infections. This study evaluated the management of snakes in three types of captivity (quarantine, intensive, and semiextensive) and diagnosed bacterial and fungal contaminants. A bacteriological profile was obtained by swabbing the oral and cloacal cavities, scales, and venoms of healthy adult snakes from Bothrops jararaca (Bj) and Crotalus durissus terrificus (Cdt). There was predominance of Enterobacteriaceae, especially non-fermenting Gram-negative bacilli excluding Pseudomonas spp and Gram- positive bacteria. Statistically, intensive captivity resulted in the highest number of bacterial isolates, followed by recent capture (quarantine) and by semiextensive captivity. No statistical difference was found between Bj and Cdt bacterial frequency. In vitro bacterial susceptibility testing found the highest resistance against the semisynthetic penicillins (amoxicillin and ampicillin) and highest sensitivity to amicacin and tobramycin aminoglycosides. To evaluate mycological profile of snakes from intensive captivity, samples were obtained from two healthy Bj and one B. moojeni, one B. pauloensis, and one Cdt showing whitish lesions on the scales suggestive of ringworm. Using conventional methods and DNA-based molecular procedures, five samples of Trichosporon asahii were identified. Despite the traditional role of intense captivity in ophidian venom production, semiextensive captivity was more effective in the present study by virtue of presenting superior control of bacterial and fungal transmission, easier management, lowest cost, and decreased rate of mortality; therefore, it should be considered as a good alternative for tropical countries.

Ruminal tryptophan-utilizing bacteria degrade ergovaline from tall fescue seed extract.

PubMed

Harlow, B E; Goodman, J P; Lynn, B C; Flythe, M D; Ji, H; Aiken, G E

2017-02-01

The objectives of this study were to evaluate degradation of ergovaline in a tall fescue [ (Schreb.) Darbysh.] seed extract by rumen microbiota ex vivo and to identify specific bacteria capable of ergovaline degradation in vitro. Rumen cell suspensions were prepared by harvesting rumen fluid from fistulated wether goats ( = 3), straining, and differential centrifugation. Suspensions were dispensed into anaerobic tubes with added Trypticase with or without extract (∼10 μg kg ergovaline). Suspensions were incubated for 48 h at 39°C. Samples were collected at 0, 24, and 48 h for ergovaline analysis and enumeration of hyper-ammonia producing (HAB) and tryptophan-utilizing bacteria. Ergovaline values were analyzed by repeated measures using the mixed procedure of SAS. Enumeration data were log transformed for statistical analysis. When suspensions were incubated with extract, 11 to 15% of ergovaline disappearance was observed over 48 h ( = 0.02). After 24 h, suspensions with added extract had 10-fold less HAB than controls ( = 0.04), but treatments were similar by 48 h ( = 1.00). However, after 24 h and 48 h, suspensions with extract had 10-fold more tryptophan-utilizing bacteria ( < 0.01) that were later isolated and identified by their 16S RNA gene sequence as . The isolates and other known rumen pure cultures ( JB1, B159, HD4, B, F, MD1, SR) were evaluated for the ability to degrade ergovaline in vitro. Pure culture cell suspensions were incubated as described above and samples were taken at 0 and 48 h for ergovaline analysis. Data were analyzed using the ANOVA procedure of SAS. All HAB, including the isolates, tested degraded ergovaline (54 to 75%; < 0.05). B14 was also able to degrade ergovaline but to a lesser capacity (12%; < 0.05), but all other bacteria tested did not degrade ergovaline. The results of this study indicate which rumen bacteria may play an important role in ergovaline degradation and that microbiological strategies for controlling their activity could have ramifications for fescue toxicosis and other forms of ergotism in ruminants.

Evaluation of an in vitro cell assay to select attenuated bacterial mutants of Aeromonas hydrophila and Edwardsiella tarda to channel catfish

USDA-ARS?s Scientific Manuscript database

To evaluate the feasibility of using an in vitro cell assay to select attenuated bacterial mutants. Using catfish gill cells G1B, the feasibility of using an in vitro assay instead of in vivo virulence assay using live fish to select attenuated bacterial mutants was evaluated in this study. Pearson ...

Management of Chronic Periodontitis Using Subgingival Irrigation of Ozonized Water: A Clinical and Microbiological Study

PubMed Central

Mathew, Jayan Jacob; Ambooken, Majo; Kachappilly, Arun Jose; PK, Ajithkumar; Johny, Thomas; VK, Linith; Samuel, Anju

2015-01-01

Introduction Adjunctive use of professional subgingival irrigation with scaling and root planing (SRP) has been found to be beneficial in eradicating the residual microorganisms in the pocket. Objective To evaluate the effect of ozonized water subgingival irrigation on microbiologic parameters and clinical parameters namely Gingival index, probing pocket depth, and clinical attachment level. Materials and Methods Thirty chronic periodontitis patients with probing pocket depth ≥6mm on at least one tooth on contra lateral sides of opposite arches were included in the study. The test sites were subjected to ozonized water subgingival irrigation with subgingival irrigation device fitted with a modified subgingival tip. Control sites were subjected to scaling and root planing only. The following clinical parameters were recorded initially and after 4 weeks at the test sites and control sites. Plaque Index, Gingival Index, probing pocket depth, clinical attachment level. Microbiologic sampling was done for the test at the baseline, after scaling, immediately after ozonized water subgingival irrigation and after 4 weeks. In control sites microbiologic sampling was done at the baseline, after scaling and after 4 weeks. The following observations were made after 4 weeks. The results were statistically analysed using independent t-test and paired t-test. Result Test sites showed a greater reduction in pocket depth and gain in clinical attachment compared to control sites. The total anaerobic counts were significantly reduced by ozonized water subgingival irrigation along with SRP compared to SRP alone. Conclusion Ozonized water subgingival irrigation can improve the clinical and microbiological parameters in patients with chronic periodontitis when used as an adjunct to scaling and root planing. PMID:26436042

Is antimicrobial photodynamic therapy an effective treatment for chronic periodontitis in diabetes mellitus and cigarette smokers: a systematic review and meta-analysis.

PubMed

Al-Hamoudi, Nawwaf

2017-09-01

To determine whether treatment with antimicrobial photodynamic therapy (aPDT) as an adjunct to scaling and root planing (SRP) improves clinical, microbiological and immunological outcomes in type 2 diabetes mellitus (T2DM) and cigarette smokers with chronic periodontitis (CP). Databases (MEDLINE, PubMed; Cochrane Central Register of Controlled Trials and Cochrane Oral Health Group Trials Register) were searched up to and including May 2017. The addressed PICO question was: "Does aPDT as an adjunct to SRP improves clinical, microbiological and immunological outcomes in T2DM and smokers with CP?" Six randomized clinical trials were included. All studies reporting clinical periodontal, microbiological, and immunological parameters showed that aPDT was effective in the treatment of CP in T2DM and smokers at follow up. When compared with SRP alone, none of the studies showed additional benefits of aPDT at follow up. Considering the effects of adjunctive aPDT as compared to SRP on clinical signs of CP in T2DM and smokers, no difference could be observed for all evaluated parameters (PD: Z=-0.81, P=0.41; CAL: Z=-0.19, P=0.84) except IL-1β (Z=4.57, P<0.001). Due to limited evidence, it remains debatable whether aPDT as an adjunct to SRP is effective in improving clinical, microbiological and immunological outcomes compared to SRP alone in T2DM and smokers with CP. Further well-designed, large-scale clinical trials with microbiological parameters and long follow up periods are needed in order to assess the efficacy of adjunctive aPDT in T2DM and cigarette smokers with CP. Copyright © 2017 Elsevier B.V. All rights reserved.

The Association between Symptoms and Microbiologically Defined Response to Tuberculosis Treatment

PubMed Central

Hales, Craig M.; Heilig, Charles M.; Chaisson, Richard; Leung, Chi Chiu; Chang, Kwok Chiu; Goldberg, Stefan V.; Gordin, Fred; Johnson, John L.; Muzanyi, Grace; Saukkonen, Jussi; Vernon, Andrew; Villarino, M. Elsa

2013-01-01

Rationale: The lack of consistent associations between clinical outcomes and microbiological responses to therapy for some infectious diseases has raised questions about the adequacy of microbiological endpoints for tuberculosis treatment trials. Objectives: To evaluate the association between symptoms and microbiological response to tuberculosis treatment. Methods: We performed a retrospective analysis of four clinical trials in which participants had culture-positive tuberculosis, standardized symptom assessment, and follow-up mycobacterial cultures. Two trials (studies 22 and 23) followed participants to identify recurrent tuberculosis; participants in studies 27 and 28 were only followed to treatment completion. Measurements and Main Results: This analysis included 1,978 participants; 39 (2.0%) had culture-confirmed treatment failure, and 75 (3.9%) had culture-confirmed recurrence. Productive cough was associated with indices of increased mycobacterial burden at diagnosis (acid-fast smear grade, severity of radiographic abnormalities). Fever and sweats improved rapidly with treatment, whereas productive cough decreased more slowly and was present in 20% of visits after treatment completion. During treatment, study participants with productive cough more often had concurrent culture positivity compared with those without productive cough (studies 22 and 23: adjusted odds ratio, 1.80; 95% confidence interval [CI], 1.33–2.44). Finally, symptoms during the latter part of treatment and follow-up were associated with culture-confirmed treatment failure and recurrence in studies 22 and 23 (for cough: adjusted hazard ratio, 2.07; 95% CI, 1.23–3.49; for fever: adjusted hazard ratio, 5.05; 95% CI, 2.76–9.19). Conclusions: There are consistent relationships between symptoms and microbiological indices of tuberculosis, including measures of mycobacterial burden at baseline, culture positivity during treatment, and time to culture-confirmed treatment failure and recurrence. PMID:23509328