Molecular approaches are powerful tools that are used for medical or environmental diagnoses. However, the main limitations of such a tools are that they extract low levels of DNA and they do not remove the inhibitors of polymerase chain reaction (PCR). Although the use of polycation to complex and purify DNA has been described in the literature, elution often requires a high ionic strength or pH levels not compatible with molecular analyses.
View Article and Find Full Text PDFrisk assessment is nowadays based on the presence and concentration of either . Many species of can cause Legionnaires' disease, indeed about half of the known species have been associated with infection. The aim of this work was to develop a method to assess the composition of the species community in an environmental sample in order to have a better understanding of the contamination of the ecosystem by pathogenic strains.
View Article and Find Full Text PDFDuring the VIABLE ISS project (eValuatIon And monitoring of microBiofiLms insidE International Space Station), water samples subjected to two different silver treatments were sent and kept on board the International Space Station (ISS) from 2011 to 2016. In this note we report data on the viable and total bacterial load and on the composition of the microbial communities of the VIABLE ISS samples.
View Article and Find Full Text PDFDuring longer-lasting future space missions, water renewal by ground-loaded supplies will become increasingly expensive and unmanageable for months. Space exploration by self-sufficient spacecrafts is thus demanding the development of culture-independent microbiological methods for in-flight water monitoring to counteract possible contamination risks. In this study, we aimed at evaluating total microbial load data assessed by selected early-warning techniques with current or promising perspectives for space applications (i.
View Article and Find Full Text PDFPerformed inside International Space Station (ISS) from 2011 to 2016, VIABLE (eValuatIon And monitoring of microBiofiLms insidE International Space Station) ISS was a long-lasting experiment aimed at evaluating the bacterial contamination on different surface space materials subjected to different pre-treatment, to provide useful information for future space missions. In this work, surfaces samples of the VIABLE ISS experiment were analyzed to determine both the total bacterial load (ATP-metry, qPCR) and the composition of the microbial communities (16S rRNA genes amplicon sequencing). Data obtained showed a low bacterial contamination of all the surfaces, with values in agreement with those allowed inside ISS, and with a taxonomic composition similar to those found in previous studies (Enterobacteriales, Bacillales, Lactobacillales and Actinomycetales).
View Article and Find Full Text PDFThe present work describes a new environmental friendly strategy for the development of surfaces with high amine density via the grafting of native or modified poly-L-lysine dendrigraft (DGL G3) onto plasma activated polypropylene (PP), polystyrene (PS), polyimide, and polytetrafluoroethylene (PTFE) surface. Modified DGL G3 was prepared by replacement of few peripheral amines by various functionalities. Grafting efficiency was determined by wettability measurements, IRTF, XPS, AFM, and by colorimetry using optimized Coomassie Brilliant Blue method tailored for surface analysis.
View Article and Find Full Text PDFAims: Virus detection has often been difficult due to a low concentration in water. In this study, we developed a new procedure based on concentration of virus particles on an innovative support: poly-L-lysine dendrigrafts (DGL), coupled with directed nucleic acid extraction and real-time PCR quantification.
Methods And Results: This method was evaluated using the bacteriophage MS2 as a model virus.
Aims: The characterization and certification of a Legionella DNA quantitative reference material as a primary measurement standard for Legionella qPCR.
Methods And Results: Twelve laboratories participated in a collaborative certification campaign. A candidate reference DNA material was analysed through PCR-based limiting dilution assays (LDAs).
A new methodology for an antibacterial assay based on capillary electrophoresis with multiple UV detection points has been proposed. The possible antibacterial activity of cationic molecules on bacteria (Gram-positive and Gram-negative) is studied by detecting the bacteria before, during, and after their meeting with the cationic antibacterial compound. For that, a UV area imaging detector having two loops and three detection windows was used with a 95 cm ×100 μm i.
View Article and Find Full Text PDFA repeatable preconcentration electrophoretic methodology for the analysis of bacteria was developed. This method is based on an isotachophoretic mode coupled with a simultaneous hydrodynamic-electrokinetic injection in conditions of field-amplified sample injection. This electrophoretic method allows the quantification of Enterobacter cloacae (studied as a model of Gram negative bacteria) with a limit of detection of 2 × 10(4) cells/mL.
View Article and Find Full Text PDFAn isotachophoretic method has been developed for mobilizing and focusing bacteria. This allows quantification and detection of bacteria in a narrow zone. Very good linearity was obtained for Micrococcus lysodeikticus (also called Micrococcus luteus, studied as a model of Gram+ bacteria) in the range of 0.
View Article and Find Full Text PDFWater Sci Technol
November 2008
The Mediterranean seaside resort of Le Grau du Roi includes 40 hectares of landscaped areas spray irrigated with river water supplied through a separate network. Wastewater collected from several municipalities is treated in an activated sludge wastewater treatment plant (WWTP) and polished in waste stabilization ponds (WSPs). Planned substitution of treated wastewater for river water is hindered by spray irrigation prohibition within a 100 m distance from houses and recreational areas.
View Article and Find Full Text PDFThe dynamics of Legionella spp. and of dominant bacteria were investigated in water from a cooling tower plant over a 9-month period which included several weeks when Legionella pneumophila proliferated. The structural diversity of both the bacteria and the Legionella spp.
View Article and Find Full Text PDFThis paper presents a new software developed for analyzing single strand conformation polymorphism (SSCP) electrophoresis patterns delivered by the genetic analyzer ABI310 (Applied Biosystems). SSCP is a molecular typing technique based on the PCR amplification of microbial 16S rDNA and used for the monitoring of complex microbial ecosystems dynamics. The software--a home-made MATLAB toolbox called MODIMECO--developed for the analysis of SSCP patterns is presented.
View Article and Find Full Text PDFThe need for criteria to compare different analytical methods for measuring extraterrestrial organic matter at ultra-trace levels in relatively small and unique samples (e.g., fragments of meteorites, micrometeorites, planetary samples) is discussed.
View Article and Find Full Text PDFThe effect of three doses of indomethacin (Indo) on BCG-induced PMN migration at different times of day was studied in Swiss mice kept on a lighting regimen of LD 12:12, with L from 07:00 to 19:00. Experimental granulomas were induced by subcutaneous implantation of BCG-impregnated cell traps for a time span of 480 min. Doses of 1, 3 and 9 mg/kg of Indo were given orally one hour before trap implantation, at 01:00, 05:00, 09:00, 13:00, 17:00 and 21:00 hr.
View Article and Find Full Text PDFThe effects of testosterone on the relative proportion of Thy 1.2, CD4 (L3T4) and CD8 (Lyt-2) cells in thymus and spleen were studied after castration and administration of Depo-testosterone (DT) separately or together with cyproterone acetate (CA) (an antiandrogen) in BDF1 mice. Injection of 0.
View Article and Find Full Text PDFThe time course of polymorphonuclear neutrophil (PMN) migration in an experimental inflammatory granuloma induced by carrageenan in the mice was studied at 6 different times of the day. Compared to saline, the number of PMN increased as soon as 240 min and reached high level at 480 min when migration was induced by carrageenan. The data showed circadian variations in the time course of cell migration.
View Article and Find Full Text PDFInt J Tissue React
August 1992
This study was performed to determine whether temporal variations could exist in polymorphonuclear neutrophil (PMN) migration induced by LPS or BCG in mice. LPS- and BCG-impregnated cell traps were implanted at 6 different times of the day and removed after 480 min. The PMN number per square unit (mm2) was counted and the results were expressed as means +/- S.
View Article and Find Full Text PDFChronobiol Int
January 1988
The temporal variation in the migration of polymorphonuclear leukocytes (PMN) induced by live BCG was studied in the mouse. Ten microliter of a 5 X 10(6) live BCG/ml suspension or sterile saline were placed on a cell trap immediately before its subcutaneous implantation at different clock times: 0100, 0500, 0900, 1300, 1700 and 2100 in animals synchronized with L(0700-1900): D(1900-0700). Eight hours later, the cell trap was removed, prepared for histological identification and counted.
View Article and Find Full Text PDFRes Commun Chem Pathol Pharmacol
August 1985
Monthly changes in the migration of polymorphonuclear leucocytes (PMN) produced by subcutaneous implantation of BCG-impregnated rayone-made disks was examined over a period of 15 months. In experiments carried out at 90h00, the highest PMN count of 40.2 +/- 8.
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