REAL TIME PCR IDENTIFICATION FOR TARGET ADJUNCTIVE ANTIBIOTIC THERAPY OF SEVERE CHRONIC PERIODONTITIS. PART II - MICROBIOLOGICAL EFFECTIVENESS.

Directory of Open Access Journals (Sweden)

Kamen Kotsilkov

2014-10-01

Full Text Available INTRODUCTION: Antibiotic use in chronic periodontitis may result in improvement in periodontal status, although many questions regarding the indications for this therapy remain unanswered. The polymicrobial etiology of the periodontal infection hinders the choice of the proper antibiotic agent. Furthermore the indiscriminate use of antibiotics could lead to high levels of resistance and to various adverse reactions. In the recent years a various molecular diagnostics protocols were proposed in order to facilitate the decision for adjunctive antibiotic administration. OBJECTIVE: The aim of this study is to compare the microbiological effectiveness of adjunctive antibiotic administration with the mechanical periodontal therapy. METHODS: 30 patients with severe chronic periodontitis were enrolled in this study and were divided in 3 groups: Control group – with mechanical debridement only. Test group 1 – with combined adjunctive antibiotic administration using Amoxicillin+ Metronidazole. Test group 2 – with target antibiotic administration according to the resuts from the Real Time PCR identification. RESULTS: The prevalence of all the isolated microorganisms (exept. E.nodatum and C.gingivalis in Test Group 2 demonstrates statistically significant reduction compared with the other treatment approaches. Almost complete elimination was registered for the consensus pathogens from the red and orange complexes (above 99% and 100% for P.intemedia. CONCLUSION: The adjunct antibiotic treatment targeted with Real-Time PCR identification demonstrates almost complete elimination of the putative periodontal pathogens in the deep periodontal pockets in patients with severe chronic periodontitis. This result suggests slower recolonisation of these habitats thus limiting the risk for progression of the periodontal destruction.

Microbiological monitoring of acid mine drainage treatment systems and aquatic surroundings using real-time PCR.

Science.gov (United States)

Han, J S; Kim, C G

2009-01-01

In general, acid mine drainage (AMD) causes low pH and high metal concentrations in mining areas and surroundings. The aim of this research was to achieve microbiological monitoring for AMD and to assess whether mine water outflows have any ecological effects on the aqueous ecosystem receiving effluents from different types of treatment system. The water quality of aquatic sample was analyzed and the molecular biological diversity of the samples was assessed using 16S rRNA methods, which were implemented to determine which bacteria existed throughout various unit processes for different AMD treatment systems and their receiving water environments. Acidiphilium cryptum, a heterotrophic acidophile, was found at the AMD sites, and Rhodoferax ferrireducens, which can reduce iron using insoluble Fe(III) as an electron acceptor, was detected at many AMD treatment facilities and downstream of the treatment processes. Subsequently, quantitative real-time PCR was conducted on specific genes of selected bacteria. Surprisingly, obvious trends were observed in the relative abundance of the various bacteria that corresponded to the water quality analytical results. The copy number of Desulfosporosinus orientus, a sulfate reducing bacteria, was also observed to decrease in response to decreases in metals according to the downstream flow of the AMD treatment system.

Shelf life of anchovy products (Engraulis encrasicolus: evaluation of sensory, microbiological and chemical properties

Directory of Open Access Journals (Sweden)

Andrea Ariano

2014-02-01

Full Text Available 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.

Diagnostic molecular microbiology: a 2013 snapshot.

Science.gov (United States)

Fairfax, Marilynn Ransom; Salimnia, Hossein

2013-12-01

Molecular testing has a large and increasing role in the diagnosis of infectious diseases. It has evolved significantly since the first probe tests were FDA approved in the early 1990s. This article highlights the uses of molecular techniques in diagnostic microbiology, including "older," as well as innovative, probe techniques, qualitative and quantitative RT-PCR, highly multiplexed PCR panels, some of which use sealed microfluidic test cartridges, MALDI TOF, and nuclear magnetic resonance. Tests are grouped together by technique and target. Tests with similar roles for similar analytes are compared with respect to benefits, drawbacks, and possible problems. Copyright © 2013 Elsevier Inc. All rights reserved.

Interlaboratory diagnostic accuracy of a Salmonella specific PCR-based method

DEFF Research Database (Denmark)

Malorny, B.; Hoorfar, Jeffrey; Hugas, M.

2003-01-01

A collaborative study involving four European laboratories was conducted to investigate the diagnostic accuracy of a Salmonella specific PCR-based method, which was evaluated within the European FOOD-PCR project (http://www.pcr.dk). Each laboratory analysed by the PCR a set of independent obtained...... presumably naturally contaminated samples and compared the results with the microbiological culture method. The PCR-based method comprised a preenrichment step in buffered peptone water followed by a thermal cell lysis using a closed tube resin-based method. Artificially contaminated minced beef and whole......-based diagnostic methods and is currently proposed as international standard document....

Changes in soil chemical and microbiological properties during 4 years of application of various organic residues.

Science.gov (United States)

Odlare, M; Pell, M; Svensson, K

2008-01-01

A 4-year field trial was established in eastern Sweden to evaluate the effects of organic waste on soil chemical and microbiological variables. A simple crop rotation with barley and oats was treated with either compost from household waste, biogas residue from household waste, anaerobically treated sewage sludge, pig manure, cow manure or mineral fertilizer. All fertilizers were amended in rates corresponding to 100kgNha(-1)year(-1). The effects of the different types of organic waste were evaluated by subjecting soil samples, taken each autumn 4 weeks after harvest, to an extensive set of soil chemical (pH, Org-C, Tot-N, Tot-P, Tot-S, P-AL, P-Olsen, K-AL, and some metals) and microbiological (B-resp, SIR, microSIR active and dormant microorganisms, PDA, microPDA, PAO, Alk-P and N-min) analyses. Results show that compost increased pH, and that compost as well as sewage sludge increased plant available phosphorus; however, the chemical analysis showed few clear trends over the 4 years and few clear relations to plant yield or soil quality. Biogas residues increased substrate induced respiration (SIR) and, compared to the untreated control amendment of biogas residues as well as compost, led to a higher proportion of active microorganisms. In addition, biogas residues increased potential ammonia oxidation rate (PAO), nitrogen mineralization capacity (N-min) as well as the specific growth rate constant of denitrifiers (microPDA). Despite rather large concentrations of heavy metals in some of the waste products, no negative effects could be seen on either chemical or microbiological soil properties. Changes in soil microbial properties appeared to occur more rapidly than most chemical properties. This suggests that soil microbial processes can function as more sensitive indicators of short-term changes in soil properties due to amendment of organic wastes.

Introduction of Molecular Methods into a Food Microbiology Curriculum

Science.gov (United States)

Pleitner, Aaron M.; Hammons, Susan R.; McKenzie, Emily; Cho, Young-Hee; Oliver, Haley F.

2014-01-01

Maintaining current, relevant curriculum in undergraduate Food Microbiology courses is essential for training future experts in food quality and safety. Having an understanding of the fundamental techniques (for example, polymerase chain reaction [PCR]) that are used in the food industry and regulatory agencies is critical for students entering…

Real-time quantitative PCR of Staphylococcus aureus and application in restaurant meals.

Science.gov (United States)

Berrada, H; Soriano, J M; Mañes, J; Picó, Y

2006-01-01

Staphylococcus aureus is considered the second most common pathogen to cause outbreaks of food poisoning, exceeded only by Campylobacter. Consumption of foods containing this microorganism is often identified as the cause of illness. In this study, a rapid, reliable, and sensitive real-time quantitative PCR was developed and compared with conventional culture methods. Real-time quantitative PCR was carried out by purifying DNA extracts of S. aureus with a Staphylococcus sample preparation kit and quantifying it in the LightCycler system with hybridization probes. The assay was linear from a range of 10 to 10(6) S. aureus cells (r2 > 0.997). The PCR reaction presented an efficiency of >85%. Accuracy of the PCR-based assay, expressed as percent bias, was around 13%, and the precision, expressed as a percentage of the coefficient of variation, was 7 to 10%. Intraday and interday variability were studied at 10(2) CFU/g and was 12 and 14%, respectively. The proposed method was applied to the analysis of 77 samples of restaurant meals in Valencia (Spain). In 11.6% of samples S. aureus was detected by real-time quantitative PCR, as well as by the conventional microbiological method. An excellent correspondence between real-time quantitative PCR and microbiological numbers (CFU/g) was observed with deviations of < 28%.

Applications of the rep-PCR DNA fingerprinting technique to study microbial diversity, ecology and evolution.

Science.gov (United States)

Ishii, Satoshi; Sadowsky, Michael J

2009-04-01

A large number of repetitive DNA sequences are found in multiple sites in the genomes of numerous bacteria, archaea and eukarya. While the functions of many of these repetitive sequence elements are unknown, they have proven to be useful as the basis of several powerful tools for use in molecular diagnostics, medical microbiology, epidemiological analyses and environmental microbiology. The repetitive sequence-based PCR or rep-PCR DNA fingerprint technique uses primers targeting several of these repetitive elements and PCR to generate unique DNA profiles or 'fingerprints' of individual microbial strains. Although this technique has been extensively used to examine diversity among variety of prokaryotic microorganisms, rep-PCR DNA fingerprinting can also be applied to microbial ecology and microbial evolution studies since it has the power to distinguish microbes at the strain or isolate level. Recent advancement in rep-PCR methodology has resulted in increased accuracy, reproducibility and throughput. In this minireview, we summarize recent improvements in rep-PCR DNA fingerprinting methodology, and discuss its applications to address fundamentally important questions in microbial ecology and evolution.

Whole genome sequencing in clinical and public health microbiology.

Science.gov (United States)

Kwong, J C; McCallum, N; Sintchenko, V; Howden, B P

2015-04-01

Genomics and whole genome sequencing (WGS) have the capacity to greatly enhance knowledge and understanding of infectious diseases and clinical microbiology.The growth and availability of bench-top WGS analysers has facilitated the feasibility of genomics in clinical and public health microbiology.Given current resource and infrastructure limitations, WGS is most applicable to use in public health laboratories, reference laboratories, and hospital infection control-affiliated laboratories.As WGS represents the pinnacle for strain characterisation and epidemiological analyses, it is likely to replace traditional typing methods, resistance gene detection and other sequence-based investigations (e.g., 16S rDNA PCR) in the near future.Although genomic technologies are rapidly evolving, widespread implementation in clinical and public health microbiology laboratories is limited by the need for effective semi-automated pipelines, standardised quality control and data interpretation, bioinformatics expertise, and infrastructure.

Real-time PCR in virology.

Science.gov (United States)

Mackay, Ian M; Arden, Katherine E; Nitsche, Andreas

2002-03-15

The use of the polymerase chain reaction (PCR) in molecular diagnostics has increased to the point where it is now accepted as the gold standard for detecting nucleic acids from a number of origins and it has become an essential tool in the research laboratory. Real-time PCR has engendered wider acceptance of the PCR due to its improved rapidity, sensitivity, reproducibility and the reduced risk of carry-over contamination. There are currently five main chemistries used for the detection of PCR product during real-time PCR. These are the DNA binding fluorophores, the 5' endonuclease, adjacent linear and hairpin oligoprobes and the self-fluorescing amplicons, which are described in detail. We also discuss factors that have restricted the development of multiplex real-time PCR as well as the role of real-time PCR in quantitating nucleic acids. Both amplification hardware and the fluorogenic detection chemistries have evolved rapidly as the understanding of real-time PCR has developed and this review aims to update the scientist on the current state of the art. We describe the background, advantages and limitations of real-time PCR and we review the literature as it applies to virus detection in the routine and research laboratory in order to focus on one of the many areas in which the application of real-time PCR has provided significant methodological benefits and improved patient outcomes. However, the technology discussed has been applied to other areas of microbiology as well as studies of gene expression and genetic disease.

Chemical, Biochemical, and Microbiological Properties of Soils from Abandoned and Extensively Cultivated Olive Orchards

Directory of Open Access Journals (Sweden)

A. M. Palese

2013-01-01

Full Text Available The abandonment of olive orchards is a phenomenon of great importance triggered mainly by economic and social causes. The aim of this study was to investigate some chemical, biochemical, and microbiological properties in a soil of a southern olive grove abandoned for 25 years. In order to define the effect of the long-term land abandonment on soil properties, an adjacent olive grove managed according to extensive practices was taken as reference (essentially minimum tillage and no fertilization. Soil organic matter, total nitrogen, and pH were significantly higher in the abandoned olive grove due to the absence of tillage and the natural inputs of organic matter at high C/N ratio which, inter alia, increased the number of cellulolytic bacteria and stimulated the activity of β-glucosidase, an indicator of a more advanced stage of soil evolution. The soil of the abandoned olive orchard showed a lower number of total bacteria and fungi and a lower microbial diversity, measured by means of the Biolog method, as a result of a sort of specialization trend towards low quality organic substrates. From this point of view, the extensive cultivation management seemed to not induce a disturbance to microbiological communities.

Chemical, Biochemical, and Microbiological Properties of Soils from Abandoned and Extensively Cultivated Olive Orchards

Science.gov (United States)

Palese, A. M.; Magno, R.; Casacchia, T.; Curci, M.; Baronti, S.; Miglietta, F.; Crecchio, C.; Xiloyannis, C.; Sofo, A.

2013-01-01

The abandonment of olive orchards is a phenomenon of great importance triggered mainly by economic and social causes. The aim of this study was to investigate some chemical, biochemical, and microbiological properties in a soil of a southern olive grove abandoned for 25 years. In order to define the effect of the long-term land abandonment on soil properties, an adjacent olive grove managed according to extensive practices was taken as reference (essentially minimum tillage and no fertilization). Soil organic matter, total nitrogen, and pH were significantly higher in the abandoned olive grove due to the absence of tillage and the natural inputs of organic matter at high C/N ratio which, inter alia, increased the number of cellulolytic bacteria and stimulated the activity of β-glucosidase, an indicator of a more advanced stage of soil evolution. The soil of the abandoned olive orchard showed a lower number of total bacteria and fungi and a lower microbial diversity, measured by means of the Biolog method, as a result of a sort of specialization trend towards low quality organic substrates. From this point of view, the extensive cultivation management seemed to not induce a disturbance to microbiological communities. PMID:24348166

A PCR procedure for the detection of Giardia intestinalis cysts and Escherichia coli in lettuce.

Science.gov (United States)

Ramirez-Martinez, M L; Olmos-Ortiz, L M; Barajas-Mendiola, M A; Giono Cerezo, S; Avila, E E; Cuellar-Mata, P

2015-06-01

Giardia intestinalis is a pathogen associated with foodborne outbreaks and Escherichia coli is commonly used as a marker of faecal contamination. Implementation of routine identification methods of G. intestinalis is difficult for the analysis of vegetables and the microbiological detection of E. coli requires several days. This study proposes a PCR-based assay for the detection of E. coli and G. intestinalis cysts using crude DNA isolated from artificially contaminated lettuce. The G. intestinalis and E. coli PCR assays targeted the β-giardin and uidA genes, respectively, and were 100% specific. Forty lettuces from local markets were analysed by both PCR and light microscopy and no cysts were detected, the calculated detection limit was 20 cysts per gram of lettuce; however, by PCR, E. coli was detected in eight of ten randomly selected samples of lettuce. These data highlight the need to validate procedures for routine quality assurance. These PCR-based assays can be employed as alternative methods for the detection of G. intestinalis and E. coli and have the potential to allow for the automation and simultaneous detection of protozoa and bacterial pathogens in multiple samples. Significance and impact of the study: There are few studies for Giardia intestinalis detection in food because methods for its identification are difficult for routine implementation. Here, we developed a PCR-based method as an alternative to the direct observation of cysts in lettuce by light microscopy. Additionally, Escherichia coli was detected by PCR and the sanitary quality of lettuce was evaluated using molecular and standard microbiological methods. Using PCR, the detection probability of Giardia cysts inoculated onto samples of lettuce was improved compared to light microscopy, with the advantage of easy automation. These methods may be employed to perform timely and affordable detection of foodborne pathogens. © 2015 The Society for Applied Microbiology.

Detection of five potentially periodontal pathogenic bacteria in peri-implant disease: A comparison of PCR and real-time PCR.

Science.gov (United States)

Schmalz, Gerhard; Tsigaras, Sandra; Rinke, Sven; Kottmann, Tanja; Haak, Rainer; Ziebolz, Dirk

2016-07-01

The aim of this study was to compare the microbial analysis methods of polymerase chain reaction (PCR) and real-time PCR (RT-PCR) in terms of detection of five selected potentially periodontal pathogenic bacteria in peri-implant disease. Therefore 45 samples of healthy, mucositis and peri-implantitis (n = 15 each) were assessed according to presence of the following bacteria using PCR (DNA-strip technology) and RT-PCR (fluorescent dye SYBR green-system): Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Treponema denticola (Td), Tanerella forsythia (Tf), and Fusobacterium nucleatum (Fn). There were no significant correlations between the bacterial and disease patterns, so the benefit of using microbiological tests for the diagnosis of peri-implant diseases is questionable. Correlations between the methods were highest for Tf (Kendall's Tau: 0.65, Spearman: 0.78), Fn (0.49, 0.61) and Td (0.49, 0.59). For Aa (0.38, 0.42) and Pg (0.04, 0.04), lower correlation values were detected. Accordingly, conventional semi-quantitative PCR seems to be sufficient for analyzing potentially periodontal pathogenic bacterial species. Copyright © 2016 Elsevier Inc. All rights reserved.

Ureaplasma parvum prosthetic joint infection detected by PCR.

Science.gov (United States)

Farrell, John J; Larson, Joshua A; Akeson, Jeffrey W; Lowery, Kristin S; Rounds, Megan A; Sampath, Rangarajan; Bonomo, Robert A; Patel, Robin

2014-06-01

We describe the first reported case of Ureaplasma parvum prosthetic joint infection (PJI) detected by PCR. Ureaplasma species do not possess a cell wall and are usually associated with colonization and infection of mucosal surfaces (not prosthetic material). U. parvum is a relatively new species name for certain serovars of Ureaplasma urealyticum, and PCR is useful for species determination. Our patient presented with late infection of his right total knee arthroplasty. Intraoperative fluid and tissue cultures and pre- and postoperative synovial fluid cultures were all negative. To discern the pathogen, we employed PCR coupled with electrospray ionization mass spectrometry (PCR/ESI-MS). Our patient's failure to respond to empirical antimicrobial treatment and our previous experience with PCR/ESI-MS in culture-negative cases of infection prompted us to use this approach over other diagnostic modalities. PCR/ESI-MS detected U. parvum in all samples. U. parvum-specific PCR testing was performed on all synovial fluid samples to confirm the U. parvum detection. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Study of irradiation effect of wheat flour on microbiological properties and on rheology of obtained dough

International Nuclear Information System (INIS)

Salem, Senda

2008-01-01

The purpose of this work is to study the effect of the irradiation by gamma rays in 1, 2, and 3 kGy on the microbiological and physico-chemical properties of the wheat flour, and on dough rheology. The rheological properties, studied by a compression-relaxation test in greased conditions are estimated by an analysis of variance approach and repeatability studies. Results show that irradiation has no effect on relaxation properties of dough. On the other hand we registered an increase of the falling number. Bread making essay shows that a dose lower than 2 kGy increased the bread volume. Reduction of the microbial load according to the dose of irradiation is also observed. (Author)

Performance of automated multiplex PCR using sonication fluid for diagnosis of periprosthetic joint infection: a prospective cohort.

Science.gov (United States)

Renz, Nora; Feihl, Susanne; Cabric, Sabrina; Trampuz, Andrej

2017-12-01

Sonication of explanted prostheses improved the microbiological diagnosis of periprosthetic joint infections (PJI). We evaluated the performance of automated multiplex polymerase chain reaction (PCR) using sonication fluid for the microbiological diagnosis of PJI. In a prospective cohort using uniform definition criteria for PJI, explanted joint prostheses were investigated by sonication and the resulting sonication fluid was analyzed by culture and multiplex PCR. McNemar's Chi-squared test was used to compare the performance of diagnostic tests. Among 111 patients, PJI was diagnosed in 78 (70%) and aseptic failure in 33 (30%). For the diagnosis of PJI, the sensitivity and specificity of periprosthetic tissue culture was 51 and 100%, of sonication fluid culture 58 and 100%, and of sonication fluid PCR 51 and 94%, respectively. Among 70 microorganisms, periprosthetic tissue culture grew 52 (74%), sonication fluid culture grew 50 (71%) and sonication fluid PCR detected 37 pathogens (53%). If only organisms are considered, for which primers are included in the test panel, PCR detected 37 of 58 pathogens (64%). The sonication fluid PCR missed 19 pathogens (predominantly oral streptococci and anaerobes), whereas 7 additional microorganisms were detected only by PCR (including Cutibacterium spp. and coagulase-negative staphylococci). The performance of multiplex PCR using sonication fluid is comparable to culture of periprosthetic tissue or sonication fluid. The advantages of PCR are short processing time (PCR, especially of low-virulent organisms.

Evaluating effects of sewage sludge and household compost on soil physical, chemical and microbiological properties

DEFF Research Database (Denmark)

Debosz, K.; Petersen, S.O.; Kure, L.K.

2002-01-01

Recycling of organic wastes within agriculture may help maintain soil fertility via effects on physical, chemical and biological properties. Efficient use, however, requires an individual assessment of waste products, and effects should be compared with natural variations due to climate and soil......C, as well as in the field. The following properties were monitored: wet-stability of soil aggregates, clay dispersibility, hot-water extractable carbohydrates, resin-extractable P-i, inorganic N, biomass C and N, PLFA profiles, FDA hydrolysis activity, beta-glucosidase activity and CO2 evolution. In general...... amendment on the fraction of soil in wet-stable aggregates, or on the microbiological properties tested, which supported the observation from the incubation study that effects of organic wastes were transient. (C) 2002 Elsevier Science B.V. All rights reserved....

Effect of the irradiation on the microbiological, physicochemical and technological properties of common wheat

International Nuclear Information System (INIS)

Benabderrahim Kaouthar

2005-01-01

In this work, we have studying the effect of irradiation dose: 1; 2; 3; 4 and 5kGy on microbiological, physico-chemical and technological properties of three wheat samples. Moreover, the effect of these irradiation doses on the lengthening of the shelf life during four months storage at room temperature was measured. Thus, the irradiation showed been efficiency on the microbiological level, in effect we observed a reduction of microbial load according to the irradiation dose. The dose of 2; 1.6 and 1.7kGy was caused the destruction of 90% of the initial aerobic total mesophyl flora respectively for the local varieties Salambo, Tebica and imported wheat. The irradiation did not cause any significant modification on the majority of the physico-chemical parameters. We can observe a reduction on humidity and an increase in fatty acidity and deterioration on the level of the starch and gluten. The α amylasic activity increase significantly with the irradiation doses. The rheological properties of the flour paste resulting from the wheat irradiated show that the irradiation caused an increase in the capacity of water absorption in the flour and reduction of the time of development, stability, elasticity and extensibility of the paste. The test of panification showed that the colour of the crust and the crumb intensify with increase of irradiation dose. During storage, the irradiated samples did not show a possible recontamination. (author). 70 refs

Microbiological monitoring in geothermal plants

Science.gov (United States)

Alawi, M.; Lerm, S.; Vetter, A.; Vieth, A.; Seibt, A.; Wolfgramm, M.; Würdemann, H.

2009-12-01

In times of increasing relevance of alternative energy resources the utilization of geothermal energy and subsurface energy storage gains importance and arouses increasing interest of scientists. The research project “AquiScreen” investigates the operational reliability of geothermally used groundwater systems under microbial, geochemical, mineralogical and petrological aspects. Microbiological analyses based on fluid and solid phases of geothermal systems are conducted to evaluate the impact of microbial populations on these systems. The presentation focuses on first results obtained from microbiological monitoring of geothermal plants located in two different regions of Germany: the North German Basin and the Molasse Basin in the southern part characterized by different salinities and temperatures. Fluid and filter samples taken during regular plant operation were investigated using genetic fingerprinting based on PCR-amplified 16S rRNA genes to characterize the microbial biocenosis of the geothermal aquifer. Sequencing of dominant bands of the fingerprints and the subsequent comparison to 16S rRNA genes from public databases enables a correlation to metabolic classes and provides information about the biochemical processes in the deep biosphere. The genetic profiles revealed significant differences in microbiological community structures of geothermal aquifers investigated. Phylogenetic analyses indicate broad metabolical diversity adapted to the specific conditions in the aquifers. Additionally a high amount of so far uncultivated microorganisms was detected indicating very specific indigenous biocenosis. However, in all geothermal plants bacteria were detected despite of fluid temperatures from 45° to 120°C. The identified microorganisms are closely related to thermophilic and hyperthermophilic species detectable in hot wells and hot springs, like Thermus scotoductus and Thermodesulfovibrio yellowstonii, respectively. Halophilic species were detected in

Real-time PCR quantification of arbuscular mycorrhizal fungi: does the use of nuclear or mitochondrial markers make a difference?

Czech Academy of Sciences Publication Activity Database

Voříšková, A.; Jansa, Jan; Püschel, David; Krüger, M.; Cajthaml, Tomáš; Vosátka, M.; Janoušková, M.

2017-01-01

Roč. 27, č. 6 (2017), s. 577-585 ISSN 0940-6360 R&D Projects: GA ČR GA15-05466S Institutional support: RVO:61388971 Keywords : Arbuscular mycorrhizal fung * Real-time PCR * PLFA Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.047, year: 2016

Mass spectrometry: a revolution in clinical microbiology?

Science.gov (United States)

Lavigne, Jean-Philippe; Espinal, Paula; Dunyach-Remy, Catherine; Messad, Nourredine; Pantel, Alix; Sotto, Albert

2013-02-01

Recently, different bacteriological laboratory interventions that decrease reporting time have been developed. These promising new broad-based techniques have merit, based on their ability to identify rapidly many bacteria, organisms difficult to grow or newly emerging strains, as well as their capacity to track disease transmission. The benefit of rapid reporting of identification and/or resistance of bacteria can greatly impact patient outcomes, with an improvement in the use of antibiotics, in the reduction of the emergence of multidrug resistant bacteria and in mortality rates. Different techniques revolve around mass spectrometry (MS) technology: matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), PCR combined with electrospray ionization-mass spectrometry (PCR/ESIMS), iPLEX MassArray system and other new evolutions combining different techniques. This report emphasizes the (r)evolution of these technologies in clinical microbiology.

Transforming clinical microbiology with bacterial genome sequencing.

Science.gov (United States)

Didelot, Xavier; Bowden, Rory; Wilson, Daniel J; Peto, Tim E A; Crook, Derrick W

2012-09-01

Whole-genome sequencing of bacteria has recently emerged as a cost-effective and convenient approach for addressing many microbiological questions. Here, we review the current status of clinical microbiology and how it has already begun to be transformed by using next-generation sequencing. We focus on three essential tasks: identifying the species of an isolate, testing its properties, such as resistance to antibiotics and virulence, and monitoring the emergence and spread of bacterial pathogens. We predict that the application of next-generation sequencing will soon be sufficiently fast, accurate and cheap to be used in routine clinical microbiology practice, where it could replace many complex current techniques with a single, more efficient workflow.

THE SIDE-EFFECT OF ORGANIC INSECTICIDE SPINOSAD ON BIOCHEMICAL AND MICROBIOLOGICAL PROPERTIES OF CLAY SOIL

Directory of Open Access Journals (Sweden)

Arkadiusz Telesiński

2015-09-01

Full Text Available The aim of the study was to determine the effect of spinosad on soil biochemical and microbiological properties. The experiment was carried out on sandy loam with Corg content 10.91 g·kg-l. Spinosad, as Spintor 240 SC was added into soil in dosages: a recommended field dosage, and fivefold, tenfold, and twenty-fivefold higher dosages. The amount of spinosad introduced into soil was between 12.55 and 313.75 g·kg-l. Moreover, soil samples without spinosad supplement were prepared as a reference. Respective Spintor 240 SC doses were converted into 1 kg soil, taking into account 10 cm depth. After application of insecticide water emulsions, soil moisture was brought to 60% maximum holding water capacity. The soil was thoroughly mixed and stored in tightly-closed polyethylene bags at 20 °C for a period 4 weeks. During the experiment dissipation of spinosad, soil enzymes (dehydrogenase, alkaline phosphatase, acid phosphatase, urease and number of bacteria, fungi, actinomycetes were assayed. Obtained results showed, that dissipation of spinosad in soil was relatively fast – the DT50 of this insecticide was ranged between 1.11 and 2.21 days. Spinosad residues had different effects on soil microbiological and biochemical properties. However, over time the impact of this insecticide definitely decreased. This indicated that the use of spinosad in organic farming, particularly in the field dosage, does not pose a long-term threat to the soil environment.

Microbiological Standardization in Small Laboratory Animals and Recommendations for the Monitoring

OpenAIRE

Meral Karaman

2014-01-01

Microbiological standardization in laboratory animal breeding is based on the classification according to the microorganisms that the animals host and consequently their upbringing environment, as well as the certification of their microbiological status and the protection of their properties. Although there are many different classifications for microbiological standardization of laboratory animals, they can be basically classified as; gnotobiotic animals, animals bred with a complete barrie...

an overview on the application of polymerase chain reaction (pcr)

African Journals Online (AJOL)

DR. AMINU

Hill New York Pp818. Chul, W.P., Jang-Hee, H., Jin-Hyeok, J. et al (2004). Detection rates of Bacteria in chronic Otitis. Media with Effusion in Children, Journal of. Korean Medical Sciences 19: 735-738. Cockerill, F.R. and Smith, T.F. (2002). Rapid-Cycle real time PCR: A revolution of clinical. Microbiology. ASM News 68:2.

Molecular identification of Mucorales in human tissues: contribution of PCR electrospray-ionization mass spectrometry.

Science.gov (United States)

Alanio, A; Garcia-Hermoso, D; Mercier-Delarue, S; Lanternier, F; Gits-Muselli, M; Menotti, J; Denis, B; Bergeron, A; Legrand, M; Lortholary, O; Bretagne, S

2015-06-01

Molecular methods are crucial for mucormycosis diagnosis because cultures are frequently negative, even if microscopy suggests the presence of hyphae in tissues. We assessed PCR/electrospray-ionization mass spectrometry (PCR/ESI-MS) for Mucorales identification in 19 unfixed tissue samples from 13 patients with proven or probable mucormycosis and compared the results with culture, quantitative real-time PCR, 16S-23S rRNA gene internal transcribed spacer region (ITS PCR) and 18S PCR sequencing. Concordance with culture identification to both genus and species levels was higher for PCR/ESI-MS than for the other techniques. Thus, PCR/ESI-MS is suitable for Mucorales identification, within 6 hours, for tissue samples for which microscopy results suggest the presence of hyphae. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Comparison between nasopharyngeal swab and nasal wash, using culture and PCR, in the detection of potential respiratory pathogens.

Science.gov (United States)

Gritzfeld, Jenna F; Roberts, Paul; Roche, Lorna; El Batrawy, Sherouk; Gordon, Stephen B

2011-04-13

Nasopharyngeal carriage of potential pathogens is important as it is both the major source of transmission and the prerequisite of invasive disease. New methods for detecting carriage could improve comfort, accuracy and laboratory utility. The aims of this study were to compare the sensitivities of a nasopharyngeal swab (NPS) and a nasal wash (NW) in detecting potential respiratory pathogens in healthy adults using microbiological culture and PCR. Healthy volunteers attended for nasal washing and brushing of the posterior nasopharynx. Conventional and real-time PCR were used to detect pneumococcus and meningococcus. Statistical differences between the two nasal sampling methods were determined using a nonparametric Mann-Whitney U test; differences between culture and PCR methods were determined using the McNemar test.Nasal washing was more comfortable for volunteers than swabbing (n = 24). In detection by culture, the NW was significantly more likely to detect pathogens than the NPS (p < 0.00001). Overall, there was a low carriage rate of pathogens in this sample; no significant difference was seen in the detection of bacteria between culture and PCR methods. Nasal washing and PCR may provide effective alternatives to nasopharyngeal swabbing and classical microbiology, respectively.

Random Amplified Polymorphic DNA PCR in the Teaching of Molecular Epidemiology

Science.gov (United States)

Reinoso, Elina B.; Bettera, Susana G.

2016-01-01

In this article, we describe a basic practical laboratory designed for fifth-year undergraduate students of Microbiology as part of the Epidemiology course. This practice provides the students with the tools for molecular epidemiological analysis of pathogenic microorganisms using a rapid and simple PCR technique. The aim of this work was to assay…

The microbiological diagnosis of tuberculous meningitis

DEFF Research Database (Denmark)

Erdem, H; Ozturk-Engin, D; Elaldi, N

2014-01-01

We aimed to provide data on the diagnosis of tuberculous meningitis (TBM) in this largest case series ever reported. The Haydarpasa-1 study involved patients with microbiologically confirmed TBM in Albania, Croatia, Denmark, Egypt, France, Hungary, Iraq, Italy, Macedonia, Romania, Serbia, Slovenia......, Syria and Turkey between 2000 and 2012. A positive culture, PCR or Ehrlich-Ziehl-Neelsen staining (EZNs) from the cerebrospinal fluid (CSF) was mandatory for inclusion of meningitis patients. A total of 506 TBM patients were included. The sensitivities of the tests were as follows: interferon-γ release.......05). Combination of L-J and ACS was superior to using these tests alone (p

Detection of intestinal protozoa in paediatric patients with gastrointestinal symptoms by multiplex real-time PCR.

Science.gov (United States)

Maas, L; Dorigo-Zetsma, J W; de Groot, C J; Bouter, S; Plötz, F B; van Ewijk, B E

2014-06-01

The performance of a multiplex real-time PCR for the detection of Blastocystis, Dientamoeba fragilis, Giardia lamblia, Cryptosporidium species and Entamoeba species in faecal samples was evaluated in an observational prospective study. Paediatric patients (0-18 years) presenting with gastrointestinal symptoms and suspected of having enteroparasitic disease were included. A questionnaire on gastrointestinal symptoms and the chosen treatment was completed at the start of the study and after 6 weeks. Of 163 paediatric patients (mean age, 7.8 years), 114 (70%) had a PCR-positive faecal sample. D. fragilis was detected most frequently, in 101 patients, followed by Blastocystis in 49. In faecal samples of 47 patients, more than one protozoan was detected, mainly the combination of D. fragilis and Blastocystis. Reported gastrointestinal symptoms were abdominal pain (78%), nausea (30%), and altered bowel habits (28%). Eighty-nine of the PCR-positive patients were treated with antibiotics. A significant reduction in abdominal pain was observed both in treated and in untreated patients. This study demonstrated that multiplex real-time PCR detects a high percentage of intestinal protozoa in paediatric patients with gastrointestinal symptoms. However, interpretation and determination of the clinical relevance of a positive PCR result in this population are still difficult. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

Comparison between nasopharyngeal swab and nasal wash, using culture and PCR, in the detection of potential respiratory pathogens

Directory of Open Access Journals (Sweden)

El Batrawy Sherouk

2011-04-01

Full Text Available Abstract Background Nasopharyngeal carriage of potential pathogens is important as it is both the major source of transmission and the prerequisite of invasive disease. New methods for detecting carriage could improve comfort, accuracy and laboratory utility. The aims of this study were to compare the sensitivities of a nasopharyngeal swab (NPS and a nasal wash (NW in detecting potential respiratory pathogens in healthy adults using microbiological culture and PCR. Results Healthy volunteers attended for nasal washing and brushing of the posterior nasopharynx. Conventional and real-time PCR were used to detect pneumococcus and meningococcus. Statistical differences between the two nasal sampling methods were determined using a nonparametric Mann-Whitney U test; differences between culture and PCR methods were determined using the McNemar test. Nasal washing was more comfortable for volunteers than swabbing (n = 24. In detection by culture, the NW was significantly more likely to detect pathogens than the NPS (p Conclusions Nasal washing and PCR may provide effective alternatives to nasopharyngeal swabbing and classical microbiology, respectively.

Tuber aestivum Vittad. mycelium quantified: advantages and limitations of a qPCR approach

Czech Academy of Sciences Publication Activity Database

Gryndler, Milan; Trilčová, Jana; Hršelová, Hana; Streiblová, Eva; Gryndlerová, Hana; Jansa, Jan

2013-01-01

Roč. 23, č. 5 (2013), s. 341-348 ISSN 0940-6360 R&D Projects: GA ČR GAP504/10/0382 Institutional support: RVO:61388971 Keywords : Summer truffle * Quantitative real-time PCR * Carpinus Subject RIV: EE - Microbiology, Virology Impact factor: 2.985, year: 2013

Colloquium and Report on Systems Microbiology: Beyond Microbial Genomics

Energy Technology Data Exchange (ETDEWEB)

Merry R. Buckley

2004-12-13

The American Academy of Microbiology convened a colloquium June 4-6, 2004 to confer about the scientific promise of systems microbiology. Participants discussed the power of applying a systems approach to the study of biology and to microbiology in particular, specifics about current research efforts, technical bottlenecks, requirements for data acquisition and maintenance, educational needs, and communication issues surrounding the field. A number of recommendations were made for removing barriers to progress in systems microbiology and for improving opportunities in education and collaboration. Systems biology, as a concept, is not new, but the recent explosion of genomic sequences and related data has revived interest in the field. Systems microbiology, a subset of systems biology, represents a different approach to investigating biological systems. It attempts to examine the emergent properties of microorganisms that arise from the interplay of genes, proteins, other macromolecules, small molecules, organelles, and the environment. It is these interactions, often nonlinear, that lead to the emergent properties of biological systems that are generally not tractable by traditional approaches. As a complement to the long-standing trend toward reductionism, systems microbiology seeks to treat the organism or community as a whole, integrating fundamental biological knowledge with genomics, metabolomics, and other data to create an integrated picture of how a microbial cell or community operates. Systems microbiology promises not only to shed light on the activities of microbes, but will also provide biology the tools and approaches necessary for achieving a better understanding of life and ecosystems. Microorganisms are ideal candidates for systems biology research because they are relatively easy to manipulate and because they play critical roles in health, environment, agriculture, and energy production. Potential applications of systems microbiology research

The diagnosis of microorganism involved in infective endocarditis (IE by polymerase chain reaction (PCR and real-time PCR: A systematic review

Directory of Open Access Journals (Sweden)

Reza Faraji

2018-02-01

Full Text Available Broad-range bacterial rDNA polymerase chain reaction (PCR followed by sequencing may be identified as the etiology of infective endocarditis (IE from surgically removed valve tissue; therefore, we reviewed the value of molecular testing in identifying organisms' DNA in the studies conducted until 2016. We searched Google Scholar, Scopus, ScienceDirect, Cochrane, PubMed, and Medline electronic databases without any time limitations up to December 2016 for English studies reporting microorganisms involved in infective endocarditis microbiology using PCR and real-time PCR. Most studies were prospective. Eleven out of 12 studies used valve tissue samples and blood cultures while only 1 study used whole blood. Also, 10 studies used the molecular method of PCR while 2 studies used real-time PCR. Most studies used 16S rDNA gene as the target gene. The bacteria were identified as the most common microorganisms involved in infective endocarditis. Streptococcus spp. and Staphylococcus spp. were, by far, the most predominant bacteria detected. In all studies, PCR and real-time PCR identified more pathogens than blood and tissue cultures; moreover, the sensitivity and specificity of PCR and real-time PCR were more than cultures in most of the studies. The highest sensitivity and specificity were 96% and 100%, respectively. The gram positive bacteria were the most frequent cause of infective endocarditis. The molecular methods enjoy a greater sensitivity compared to the conventional blood culture methods; yet, they are applicable only to the valve tissue of the patients undergoing cardiac valve surgery.

The diagnosis of microorganism involved in infective endocarditis (IE) by polymerase chain reaction (PCR) and real-time PCR: A systematic review.

Science.gov (United States)

Faraji, Reza; Behjati-Ardakani, Mostafa; Moshtaghioun, Seyed Mohammad; Kalantar, Seyed Mehdi; Namayandeh, Seyedeh Mahdieh; Soltani, Mohammadhossien; Emami, Mahmood; Zandi, Hengameh; Firoozabadi, Ali Dehghani; Kazeminasab, Mahmood; Ahmadi, Nastaran; Sarebanhassanabadi, Mohammadtaghi

2018-02-01

Broad-range bacterial rDNA polymerase chain reaction (PCR) followed by sequencing may be identified as the etiology of infective endocarditis (IE) from surgically removed valve tissue; therefore, we reviewed the value of molecular testing in identifying organisms' DNA in the studies conducted until 2016. We searched Google Scholar, Scopus, ScienceDirect, Cochrane, PubMed, and Medline electronic databases without any time limitations up to December 2016 for English studies reporting microorganisms involved in infective endocarditis microbiology using PCR and real-time PCR. Most studies were prospective. Eleven out of 12 studies used valve tissue samples and blood cultures while only 1 study used whole blood. Also, 10 studies used the molecular method of PCR while 2 studies used real-time PCR. Most studies used 16S rDNA gene as the target gene. The bacteria were identified as the most common microorganisms involved in infective endocarditis. Streptococcus spp. and Staphylococcus spp. were, by far, the most predominant bacteria detected. In all studies, PCR and real-time PCR identified more pathogens than blood and tissue cultures; moreover, the sensitivity and specificity of PCR and real-time PCR were more than cultures in most of the studies. The highest sensitivity and specificity were 96% and 100%, respectively. The gram positive bacteria were the most frequent cause of infective endocarditis. The molecular methods enjoy a greater sensitivity compared to the conventional blood culture methods; yet, they are applicable only to the valve tissue of the patients undergoing cardiac valve surgery. Copyright © 2017. Published by Elsevier Taiwan.

Effect of Oregano Essential Oil and Aqueous Oregano Infusion Application on Microbiological Properties of Samarella (Tsamarella), a Traditional Meat Product of Cyprus.

Science.gov (United States)

Ulusoy, Beyza; Hecer, Canan; Kaynarca, Doruk; Berkan, Şifa

2018-03-21

Different types of dried meat products manufactured by different drying and curing methods are very common and well-known with a long history all over the world. Samarella (tsamarella) is one of these products and is famous among traditionally produced meat products in Cypriot gastronomy. The aim of this study was to investigate the effect of oregano essential oil (OEO) and aqueous oregano infusion (AOI) applications on the microbiological properties of samarella. In order to carry out this study, traditional methods were followed for experimental production of samarella. As a result of this study, five percent OEO application was found to be more effective to reduce microbiological counts but this ratio of OEO application was not accepted by panelists. According to all microbiological results correlated with the sensorial scores, it is concluded that one percent OEO application can be used for samarella production as an alternative preservative method.

Effect of Oregano Essential Oil and Aqueous Oregano Infusion Application on Microbiological Properties of Samarella (Tsamarella, a Traditional Meat Product of Cyprus

Directory of Open Access Journals (Sweden)

Beyza Ulusoy

2018-03-01

Full Text Available Different types of dried meat products manufactured by different drying and curing methods are very common and well-known with a long history all over the world. Samarella (tsamarella is one of these products and is famous among traditionally produced meat products in Cypriot gastronomy. The aim of this study was to investigate the effect of oregano essential oil (OEO and aqueous oregano infusion (AOI applications on the microbiological properties of samarella. In order to carry out this study, traditional methods were followed for experimental production of samarella. As a result of this study, five percent OEO application was found to be more effective to reduce microbiological counts but this ratio of OEO application was not accepted by panelists. According to all microbiological results correlated with the sensorial scores, it is concluded that one percent OEO application can be used for samarella production as an alternative preservative method.

Efficacy of a novel PCR- and microarray-based method in diagnosis of a prosthetic joint infection

Science.gov (United States)

2014-01-01

Background and purpose Polymerase chain reaction (PCR) methods enable detection and species identification of many pathogens. We assessed the efficacy of a new PCR and microarray-based platform for detection of bacteria in prosthetic joint infections (PJIs). Methods This prospective study involved 61 suspected PJIs in hip and knee prostheses and 20 negative controls. 142 samples were analyzed by Prove-it Bone and Joint assay. The laboratory staff conducting the Prove-it analysis were not aware of the results of microbiological culture and clinical findings. The results of the analysis were compared with diagnosis of PJIs defined according to the Musculoskeletal Infection Society (MSIS) criteria and with the results of microbiological culture. Results 38 of 61 suspected PJIs met the definition of PJI according to the MSIS criteria. Of the 38 patients, the PCR detected bacteria in 31 whereas bacterial culture was positive in 28 patients. 15 of the PJI patients were undergoing antimicrobial treatment as the samples for analysis were obtained. When antimicrobial treatment had lasted 4 days or more, PCR detected bacteria in 6 of the 9 patients, but positive cultures were noted in only 2 of the 9 patients. All PCR results for the controls were negative. Of the 61 suspected PJIs, there were false-positive PCR results in 6 cases. Interpretation The Prove-it assay was helpful in PJI diagnostics during ongoing antimicrobial treatment. Without preceding treatment with antimicrobials, PCR and microarray-based assay did not appear to give any additional information over culture. PMID:24564748

Application of PCR-mediated DNA typing in the molecular epidemiology of medically important microorganisms

NARCIS (Netherlands)

A.F. van Belkum (Alex)

1996-01-01

textabstractThis thesis describes the development, application and validation of the newer DNA analysis techniques within the field of microbiological epidemiology. Emphasis is placed on the use of the polymerase chain reaction (PCR), a test-tube technique enabling the amplification of (parts of)

Detection of bacterial species involved in perimplantitis concerned with cultural and RT-PCR

Directory of Open Access Journals (Sweden)

Marcello Gatti

2010-06-01

Full Text Available Dental implants offer new treatment options for edentulous either partially or completely, now represent a viable alternative to conventional fixed protheses. Dental implants are colonized by a flora dominated by Gram-positive facultative aerobic, while in patients with bone loss and formation of pockets peri-implant diseases was found a significant difference in the composition of microflora, bacteria, Gram-negative anaerobes in particular Fusobacterium spp., Treponema denticola (Spirochetes, Tannerella forsythensis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia as interim black-pigmented bacteria, Porphyromonas gingivalis, often in high concentrations. Aims. The purpose of this study was to identify those at risk of perimplantitis using 2 techniques: RT-PCR examination of trade and culture. The results were compared taking into consideration the advantages and disadvantages of both methods. Materials and methods.We studied 24 patients (14 women and 10 men, aged, women between 43 and 76 years, with an average of 63.8 + / - 10.9 years, men between 45 and 88 years with a average of 64.3 years + / - 12.5 years. Was performed a double levy of sub-gingival plaque at multiple sites that had an implant CAL (clinical attachment level> 4mm in order to assess the microbiological identification with the two techniques: Examining culture and Real-Time PCR of Commerce ( Gum-Sunstar that identifies 4 bacterial species: A. actinomycetemcomitans (A.a., P.gingivalis (P.g., T.forsythensis (T.f., and T.denticola (T.d.. Results. All patients studied were positive to both tests with charger high: the consideration of tenure, with CFU / ml > 105, was positive in 66.6% of samples by:T.f., and P.g., in 12.5% for A.a., while T.d. not been sought by examining culture, the RT-PCR was positive, with high loads, in 95.8% of samples for T.f., in 79.1% for P.g., in 12.5% for A.a. and 20.8% for T.d.The test crop showed the presence of even P.intermedia in 91

A study of relations between physicochemical properties of crude oils and microbiological characteristics of reservoir microflora

Science.gov (United States)

Yashchenko, I. G.; Polishchuk, Yu. M.; Peremitina, T. O.

2015-10-01

The dependence of the population and activity of reservoir microflora upon the chemical composition and viscosity of crude oils has been investigated, since it allows the problem of improvement in the technologies and enhancement of oil recovery as applied to production of difficult types of oils with anomalous properties (viscous, heavy, waxy, high resin) to be solved. The effect of the chemical composition of the oil on the number, distribution, and activity of reservoir microflora has been studied using data on the microbiological properties of reservoir water of 16 different fields in oil and gas basins of Russia, Mongolia, China, and Vietnam. Information on the physicochemical properties of crude oils of these fields has been obtained from the database created at the Institute of Petroleum Chemistry, Siberian Branch on the physicochemical properties of oils throughout the world. It has been found that formation water in viscous oil reservoirs is char acterized by a large population of heterotrophic and sulfate reducing bacteria and the water of oil fields with a high paraffin content, by population of denitrifying bacteria.

Comparison of PCR/Electron spray Ionization-Time-of-Flight-Mass Spectrometry versus Traditional Clinical Microbiology for active surveillance of organisms contaminating high-use surfaces in a burn intensive care unit, an orthopedic ward and healthcare workers

Directory of Open Access Journals (Sweden)

Yun Heather C

2012-10-01

Full Text Available Abstract Background Understanding nosocomial pathogen transmission is restricted by culture limitations. Novel platforms, such as PCR-based electron spray ionization-time-of-flight-mass spectrometry (ESI-TOF-MS, may be useful as investigational tools. Methods Traditional clinical microbiology (TCM and PCR/ESI-TOF-MS were used to recover and detect microorganisms from the hands and personal protective equipment of 10 burn intensive care unit (ICU healthcare workers providing clinical care at a tertiary care military referral hospital. High-use environmental surfaces were assessed in 9 burn ICU and 10 orthopedic patient rooms. Clinical cultures during the study period were reviewed for pathogen comparison with investigational molecular diagnostic methods. Results From 158 samples, 142 organisms were identified by TCM and 718 by PCR/ESI-TOF-MS. The molecular diagnostic method detected more organisms (4.5 ± 2.1 vs. 0.9 ± 0.8, p S. aureus in 13 samples vs. 21 by PCR/ESI-TOF-MS. Gram-negative organisms were less commonly identified than gram-positive by both methods; especially by TCM. Among all detected bacterial species, similar percentages were typical nosocomial pathogens (18-19% for TCM vs. PCR/ESI-TOF-MS. PCR/ESI-TOF-MS also detected mecA in 112 samples, vanA in 13, and KPC-3 in 2. MecA was associated (p S. aureus. No vanA was codetected with enterococci; one KPC-3 was detected without Klebsiella spp. Conclusions In this pilot study, PCR/ESI-TOF-MS detected more organisms, especially gram-negatives, compared to TCM, but the current assay format is limited by the number of antibiotic resistance determinants it covers. Further large-scale assessments of PCR/ESI-TOF-MS for hospital surveillance are warranted.

Comparison of PCR/electron spray ionization-time-of-flight-mass spectrometry versus traditional clinical microbiology for active surveillance of organisms contaminating high-use surfaces in a burn intensive care unit, an orthopedic ward and healthcare workers.

Science.gov (United States)

Yun, Heather C; Kreft, Rachael E; Castillo, Mayra A; Ehrlich, Garth D; Guymon, Charles H; Crouch, Helen K; Chung, Kevin K; Wenke, Joseph C; Hsu, Joseph R; Spirk, Tracy L; Costerton, J William; Mende, Katrin; Murray, Clinton K

2012-10-10

Understanding nosocomial pathogen transmission is restricted by culture limitations. Novel platforms, such as PCR-based electron spray ionization-time-of-flight-mass spectrometry (ESI-TOF-MS), may be useful as investigational tools. Traditional clinical microbiology (TCM) and PCR/ESI-TOF-MS were used to recover and detect microorganisms from the hands and personal protective equipment of 10 burn intensive care unit (ICU) healthcare workers providing clinical care at a tertiary care military referral hospital. High-use environmental surfaces were assessed in 9 burn ICU and 10 orthopedic patient rooms. Clinical cultures during the study period were reviewed for pathogen comparison with investigational molecular diagnostic methods. From 158 samples, 142 organisms were identified by TCM and 718 by PCR/ESI-TOF-MS. The molecular diagnostic method detected more organisms (4.5 ± 2.1 vs. 0.9 ± 0.8, p < 0.01) from 99% vs. 67% of samples (p < 0.01). TCM detected S. aureus in 13 samples vs. 21 by PCR/ESI-TOF-MS. Gram-negative organisms were less commonly identified than gram-positive by both methods; especially by TCM. Among all detected bacterial species, similar percentages were typical nosocomial pathogens (18-19%) for TCM vs. PCR/ESI-TOF-MS. PCR/ESI-TOF-MS also detected mecA in 112 samples, vanA in 13, and KPC-3 in 2. MecA was associated (p < 0.01) with codetection of coagulase negative staphylococci but not S. aureus. No vanA was codetected with enterococci; one KPC-3 was detected without Klebsiella spp. In this pilot study, PCR/ESI-TOF-MS detected more organisms, especially gram-negatives, compared to TCM, but the current assay format is limited by the number of antibiotic resistance determinants it covers. Further large-scale assessments of PCR/ESI-TOF-MS for hospital surveillance are warranted.

Advances Afoot in Microbiology.

Science.gov (United States)

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.

Evaluation of Legionella real-time PCR against traditional culture for routine and public health testing of water samples.

Science.gov (United States)

Collins, S; Stevenson, D; Walker, J; Bennett, A

2017-06-01

To evaluate the usefulness of Legionella qPCR alongside traditional culture for enumeration of Legionella from water samples as part of both routine and public health investigation testing. Routine water samples (n = 2002) and samples from public health investigations (n = 215) were analysed by culture and qPCR for Legionella spp., Legionella pneumophila and L. pneumophila sg-1. A negative qPCR result was highly predictive of a negative culture result for all water systems (negative predictive values, NPV from 97·4 to 100%). Positive predictive values (PPV) were lower (0-50%). Results for qPCR were generally larger than culture with average log 10 differences of 1·1 for Legionella spp. and 1·2 for L. pneumophila. Alert and action levels of 1000 and 10 000 GU per litre, respectively, are proposed for Legionella qPCR for hot and cold water systems (HCWS). The use of qPCR significantly reduced the time to results for public health investigations by rapidly identifying potential sources and ruling out others, thus enabling a more rapid and efficient response. The high NPV of qPCR supports its use to rapidly screen out negative samples without culture. Alert and action levels for Legionella qPCR for HCWS are proposed. Quantitative PCR will be a valuable tool for both routine and public health testing. This study generated comparative data of >2000 water samples by qPCR and culture. Action and alert levels have been recommended that could enable duty holders to interpret qPCR results to facilitate timely Legionella control and public health protection. © 2017 Crown copyright. Journal of Applied Microbiology © 2017 The Society for Applied Microbiology.

Microbiological and chemical properties of litter from different chicken types and production systems

International Nuclear Information System (INIS)

Omeira, N.; Barbour, E.K.; Nehme, P.A.; Hamadeh, S.K.; Zurayk, R.; Bashour, I.

2006-01-01

Chicken litter is produced in large quantities from all types of poultry raising activities. It is primarily used for land application, thus it is essential to analyze its properties before it is released to the environment. The objective of this study is to compare the microbiological and chemical properties of litter generated from layer and broiler chickens reared under intensive and free-range production systems. The microbiological analysis consisted of the enumeration of total bacteria, total coliforms, Staphylococcus species, Salmonella species and Clostridium perfringens. Chicken litter from layers reared under intensive and free range systems showed lower mean total bacterial count than the litter collected from chicken broilers reared under either of the two systems (P = 0.0291). The litter from intensive layers had the lowest mean total coliform counts (P = 0.0222) while the lowest Staphylococcus species count was observed in the litter from free-range layers (P = 0.0077). The C. perfringens count was the lowest in chicken litter from intensively raised broilers and layers (P = 0.0001). The chemical properties of litter from the different chicken types and production systems were compared based on determination of pH, electrical conductivity, carbon, nitrogen, phosphorus, potassium, cadmium and zinc. Litter from free-range broilers showed the highest pH value (P = 0.0005); however, the electrical conductivity was higher in the litter from both intensive and free-range layers compared to the litter from both broiler production systems (P = 0.0117). Chicken litter from intensive systems had higher nitrogen content than litter from free-range systems (P = 0.0000). The total phosphorus was the lowest in free-range broiler litter (P = 0.0001), while the total potassium was the lowest in litter from intensively managed broilers (P = 0.0000). Zinc appeared higher in litter from layers compared to that from broilers (P = 0.0101). The cadmium content was higher

Microbiological and chemical properties of litter from different chicken types and production systems.

Science.gov (United States)

Omeira, N; Barbour, E K; Nehme, P A; Hamadeh, S K; Zurayk, R; Bashour, I

2006-08-15

Chicken litter is produced in large quantities from all types of poultry raising activities. It is primarily used for land application, thus it is essential to analyze its properties before it is released to the environment. The objective of this study is to compare the microbiological and chemical properties of litter generated from layer and broiler chickens reared under intensive and free-range production systems. The microbiological analysis consisted of the enumeration of total bacteria, total coliforms, Staphylococcus species, Salmonella species and Clostridium perfringens. Chicken litter from layers reared under intensive and free range systems showed lower mean total bacterial count than the litter collected from chicken broilers reared under either of the two systems (P=0.0291). The litter from intensive layers had the lowest mean total coliform counts (P=0.0222) while the lowest Staphylococcus species count was observed in the litter from free-range layers (P=0.0077). The C. perfringens count was the lowest in chicken litter from intensively raised broilers and layers (P=0.0001). The chemical properties of litter from the different chicken types and production systems were compared based on determination of pH, electrical conductivity, carbon, nitrogen, phosphorus, potassium, cadmium and zinc. Litter from free-range broilers showed the highest pH value (P=0.0005); however, the electrical conductivity was higher in the litter from both intensive and free-range layers compared to the litter from both broiler production systems (P=0.0117). Chicken litter from intensive systems had higher nitrogen content than litter from free-range systems (P=0.0000). The total phosphorus was the lowest in free-range broiler litter (P=0.0001), while the total potassium was the lowest in litter from intensively managed broilers (P=0.0000). Zinc appeared higher in litter from layers compared to that from broilers (P=0.0101). The cadmium content was higher in the litter from

Microbiological and chemical properties of litter from different chicken types and production systems

Energy Technology Data Exchange (ETDEWEB)

Omeira, N. [Department of Land and Water Resources, Faculty of Agricultural and Food Sciences, American University of Beirut, Beirut (Lebanon); Barbour, E.K. [Department of Animal Sciences, Faculty of Agricultural and Food Sciences, American University of Beirut, Beirut (Lebanon)]. E-mail: eb01@aub.edu.lb; Nehme, P.A. [Department of Land and Water Resources, Faculty of Agricultural and Food Sciences, American University of Beirut, Beirut (Lebanon); Hamadeh, S.K. [Department of Animal Sciences, Faculty of Agricultural and Food Sciences, American University of Beirut, Beirut (Lebanon); Zurayk, R. [Department of Land and Water Resources, Faculty of Agricultural and Food Sciences, American University of Beirut, Beirut (Lebanon); Bashour, I. [Department of Land and Water Resources, Faculty of Agricultural and Food Sciences, American University of Beirut, Beirut (Lebanon)

2006-08-15

Chicken litter is produced in large quantities from all types of poultry raising activities. It is primarily used for land application, thus it is essential to analyze its properties before it is released to the environment. The objective of this study is to compare the microbiological and chemical properties of litter generated from layer and broiler chickens reared under intensive and free-range production systems. The microbiological analysis consisted of the enumeration of total bacteria, total coliforms, Staphylococcus species, Salmonella species and Clostridium perfringens. Chicken litter from layers reared under intensive and free range systems showed lower mean total bacterial count than the litter collected from chicken broilers reared under either of the two systems (P = 0.0291). The litter from intensive layers had the lowest mean total coliform counts (P = 0.0222) while the lowest Staphylococcus species count was observed in the litter from free-range layers (P = 0.0077). The C. perfringens count was the lowest in chicken litter from intensively raised broilers and layers (P = 0.0001). The chemical properties of litter from the different chicken types and production systems were compared based on determination of pH, electrical conductivity, carbon, nitrogen, phosphorus, potassium, cadmium and zinc. Litter from free-range broilers showed the highest pH value (P = 0.0005); however, the electrical conductivity was higher in the litter from both intensive and free-range layers compared to the litter from both broiler production systems (P = 0.0117). Chicken litter from intensive systems had higher nitrogen content than litter from free-range systems (P = 0.0000). The total phosphorus was the lowest in free-range broiler litter (P = 0.0001), while the total potassium was the lowest in litter from intensively managed broilers (P = 0.0000). Zinc appeared higher in litter from layers compared to that from broilers (P = 0.0101). The cadmium content was higher

PCR assay for the detection of Campylobacter in marinated and non-marinated poultry products

DEFF Research Database (Denmark)

Katzav, Marianne; Isohanni, Pauliina; Lund, Marianne

2008-01-01

and chicken products, respectively. In August, there was a peak with 28.9% positive Campylobacter samples. Campylobacter inoculation tests were carried out to test the detection limit of both methods. The PCR method used is faster than microbiological analyses. However, enrichment of the samples is necessary...

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

Science.gov (United States)

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.

Comparison of viable plate count, turbidity measurement and real-time PCR for quantification of Porphyromonas gingivalis.

Science.gov (United States)

Clais, S; Boulet, G; Van Kerckhoven, M; Lanckacker, E; Delputte, P; Maes, L; Cos, P

2015-01-01

The viable plate count (VPC) is considered as the reference method for bacterial enumeration in periodontal microbiology but shows some important limitations for anaerobic bacteria. As anaerobes such as Porphyromonas gingivalis are difficult to culture, VPC becomes time-consuming and less sensitive. Hence, efficient normalization of experimental data to bacterial cell count requires alternative rapid and reliable quantification methods. This study compared the performance of VPC with that of turbidity measurement and real-time PCR (qPCR) in an experimental context using highly concentrated bacterial suspensions. Our TaqMan-based qPCR assay for P. gingivalis 16S rRNA proved to be sensitive and specific. Turbidity measurements offer a fast method to assess P. gingivalis growth, but suffer from high variability and a limited dynamic range. VPC was very time-consuming and less repeatable than qPCR. Our study concludes that qPCR provides the most rapid and precise approach for P. gingivalis quantification. Although our data were gathered in a specific research context, we believe that our conclusions on the inferior performance of VPC and turbidity measurements in comparison to qPCR can be extended to other research and clinical settings and even to other difficult-to-culture micro-organisms. Various clinical and research settings require fast and reliable quantification of bacterial suspensions. The viable plate count method (VPC) is generally seen as 'the gold standard' for bacterial enumeration. However, VPC-based quantification of anaerobes such as Porphyromonas gingivalis is time-consuming due to their stringent growth requirements and shows poor repeatability. Comparison of VPC, turbidity measurement and TaqMan-based qPCR demonstrated that qPCR possesses important advantages regarding speed, accuracy and repeatability. © 2014 The Society for Applied Microbiology.

DNA microarray-based PCR ribotyping of Clostridium difficile.

Science.gov (United States)

Schneeberg, Alexander; Ehricht, Ralf; Slickers, Peter; Baier, Vico; Neubauer, Heinrich; Zimmermann, Stefan; Rabold, Denise; Lübke-Becker, Antina; Seyboldt, Christian

2015-02-01

This study presents a DNA microarray-based assay for fast and simple PCR ribotyping of Clostridium difficile strains. Hybridization probes were designed to query the modularly structured intergenic spacer region (ISR), which is also the template for conventional and PCR ribotyping with subsequent capillary gel electrophoresis (seq-PCR) ribotyping. The probes were derived from sequences available in GenBank as well as from theoretical ISR module combinations. A database of reference hybridization patterns was set up from a collection of 142 well-characterized C. difficile isolates representing 48 seq-PCR ribotypes. The reference hybridization patterns calculated by the arithmetic mean were compared using a similarity matrix analysis. The 48 investigated seq-PCR ribotypes revealed 27 array profiles that were clearly distinguishable. The most frequent human-pathogenic ribotypes 001, 014/020, 027, and 078/126 were discriminated by the microarray. C. difficile strains related to 078/126 (033, 045/FLI01, 078, 126, 126/FLI01, 413, 413/FLI01, 598, 620, 652, and 660) and 014/020 (014, 020, and 449) showed similar hybridization patterns, confirming their genetic relatedness, which was previously reported. A panel of 50 C. difficile field isolates was tested by seq-PCR ribotyping and the DNA microarray-based assay in parallel. Taking into account that the current version of the microarray does not discriminate some closely related seq-PCR ribotypes, all isolates were typed correctly. Moreover, seq-PCR ribotypes without reference profiles available in the database (ribotype 009 and 5 new types) were correctly recognized as new ribotypes, confirming the performance and expansion potential of the microarray. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Soil microbiological properties and enzymatic activities of long-term post-fire recovery in dry and semiarid Aleppo pine (Pinus halepensis M.) forest stands

Science.gov (United States)

Hedo, J.; Lucas-Borja, M. E.; Wic, C.; Andrés-Abellán, M.; de Las Heras, J.

2015-02-01

Wildfires affecting forest ecosystems and post-fire silvicultural treatments may cause considerable changes in soil properties. The capacity of different microbial groups to recolonise soil after disturbances is crucial for proper soil functioning. The aim of this work was to investigate some microbial soil properties and enzyme activities in semiarid and dry Aleppo pine (Pinus halepensis M.) forest stands. Different plots affected by a wildfire event 17 years ago without or with post-fire silvicultural treatments 5 years after the fire event were selected. A mature Aleppo pine stand, unaffected by wildfire and not thinned was used as a control. Physicochemical soil properties (soil texture, pH, carbonates, organic matter, electrical conductivity, total N and P), soil enzymes (urease, phosphatase, β-glucosidase and dehydrogenase activities), soil respiration and soil microbial biomass carbon were analysed in the selected forests areas and plots. The main finding was that long time after this fire event produces no differences in the microbiological soil properties and enzyme activities of soil after comparing burned and thinned, burned and not thinned, and mature plots. Moreover, significant site variation was generally seen in soil enzyme activities and microbiological parameters. We conclude that total vegetation recovery normalises post-fire soil microbial parameters, and that wildfire and post-fire silvicultural treatments are not significant factors affecting soil properties after 17 years.

Automated micro fluidic system for PCR applications in the monitoring of drinking water quality

International Nuclear Information System (INIS)

Soria Soria, E.; Yanez Amoros, A.; Murtula Corbi, R.; Catalan Cuenca, V.; Martin-Cisneros, C. S.; Ymbern, O.; Alonso-Chamorro, J.

2009-01-01

Microbiological laboratories present a growing interest in automated, simple and user-friendly methodologies able to perform simultaneous analysis of a high amount of samples. Analytical tools based on micro-fluidic could play an important role in this field. In this work, the development of an automated micro fluidic system for PCR applications and aimed to monitoring of drinking water quality is presented. The device will be able to determine, simultaneously, fecal pollution indicators and water-transmitted pathogens. Further-more, complemented with DNA pre-concentration and extraction modules, the device would present a highly integrated solution for microbiological diagnostic laboratories. (Author) 13 refs.

Multiplexed Single Intact Cell Droplet Digital PCR (MuSIC ddPCR) Method for Specific Detection of Enterohemorrhagic E. coli (EHEC) in Food Enrichment Cultures

OpenAIRE

McMahon, Tanis C.; Blais, Burton W.; Wong, Alex; Carrillo, Catherine D.

2017-01-01

Foodborne illness attributed to enterohemorrhagic E. coli (EHEC), a highly pathogenic subset of Shiga toxin-producing E. coli (STEC), is increasingly recognized as a significant public health issue. Current microbiological methods for identification of EHEC in foods often use PCR-based approaches to screen enrichment broth cultures for characteristic gene markers [i.e., Shiga toxin (stx) and intimin (eae)]. However, false positives arise when complex food matrices, such as beef, contain mixtu...

Microbiological Methodology in Astrobiology

Science.gov (United States)

Abyzov, S. S.; Gerasimenko, L. M.; Hoover, R. B.; Mitskevich, I. N.; Mulyukin, A. L.; Poglazova, M. N.; Rozanov, A. Y.

2005-01-01

Searching for life in astromaterials to be delivered from the future missions to extraterrestrial bodies is undoubtedly related to studies of the properties and signatures of living microbial cells and microfossils on Earth. As model terrestrial analogs of Martian polar subsurface layers are often regarded the Antarctic glacier and Earth permafrost habitats where alive microbial cells preserved viability for millennia years due to entering the anabiotic state. For the future findings of viable microorganisms in samples from extraterrestrial objects, it is important to use a combined methodology that includes classical microbiological methods, plating onto nutrient media, direct epifluorescence and electron microscopy examinations, detection of the elemental composition of cells, radiolabeling techniques, PCR and FISH methods. Of great importance is to ensure authenticity of microorganisms (if any in studied samples) and to standardize the protocols used to minimize a risk of external contamination. Although the convincing evidence of extraterrestrial microbial life will may come from the discovery of living cells in astromaterials, biomorphs and microfossils must also be regarded as a target in search of life evidence bearing in mind a scenario that alive microorganisms had not be preserved and underwent mineralization. Under the laboratory conditions, processes that accompanied fossilization of cyanobacteria were reconstructed, and artificially produced cyanobacterial stromatolites resembles by their morphological properties those found in natural Earth habitats. Regarding the vital importance of distinguishing between biogenic and abiogenic signatures and between living and fossil microorganisms in analyzed samples, it is worthwhile to use some previously developed approaches based on electron microscopy examinations and analysis of elemental composition of biomorphs in situ and comparison with the analogous data obtained for laboratory microbial cultures and

Feasibility of shortening isolation of TB-suspects by first-sample PCR

DEFF Research Database (Denmark)

Fløe, Andreas; Wejse, Christian; Thomsen, Vibeke Østergaard

Rationale: Isolation of patients suspected for tuberculosis (TB) is usually guided by serial sputum smears. Many of patients initially isolated will turn out not to have TB, or will not be regarded as contagious. Current standards imply isolation for hours or days until contagiousness has been...... excluded. Objective: To evaluate the utility of single-specimen polymerase chain-reaction (PCR) for Mycobacterium tuberculosis complex (MTBC) as a parameter to cease isolation when negative. Methods: We evaluated all patients in Denmark who had sputa investigated for MTBC at the National Reference......-positive on the sample that produced the PCR-negative result. Conclusion: Though adequate sensitivity in diagnosing TB still requires serial samples for microbiological examination, the question of isolation can be determined by first-sample PCR in the majority of cases, when the test is negative. In our study, less...

Sequence diversity in haloalkane dehalogenases, as revealed by PCR using family-specific primers

Czech Academy of Sciences Publication Activity Database

Kotík, Michael; Faměrová, Veronika

2012-01-01

Roč. 88, č. 2 (2012), s. 212-217 ISSN 0167-7012 R&D Projects: GA ČR GAP504/10/0137; GA ČR GAP207/10/0135 Institutional research plan: CEZ:AV0Z50200510 Keywords : Dehalogenation * Consensus sequence * Degenerate PCR primer Subject RIV: EE - Microbiology, Virology Impact factor: 2.161, year: 2012

Microbiological testing of pharmaceuticals and cosmetics in Egypt.

Science.gov (United States)

Zeitoun, Hend; Kassem, Mervat; Raafat, Dina; AbouShlieb, Hamida; Fanaki, Nourhan

2015-12-09

Microbial contamination of pharmaceuticals poses a great problem to the pharmaceutical manufacturing process, especially from a medical as well as an economic point of view. Depending upon the product and its intended use, the identification of isolates should not merely be limited to the United States Pharmacopeia (USP) indicator organisms. Eighty-five pre-used non-sterile pharmaceuticals collected from random consumers in Egypt were examined for the eventual presence of bacterial contaminants. Forty-one bacterial contaminants were isolated from 31 of the tested preparations. These isolates were subjected to biochemical identification by both conventional tests as well as API kits, which were sufficient for the accurate identification of only 11 out of the 41 bacterial contaminants (26.8%) to the species level. The remaining isolates were inconclusively identified or showed contradictory results after using both biochemical methods. Using molecular methods, 24 isolates (58.5%) were successfully identified to the species level. Moreover, polymerase chain reaction (PCR) assays were compared to standard biochemical methods in the detection of pharmacopoeial bacterial indicators in artificially-contaminated pharmaceutical samples. PCR-based methods proved to be superior regarding speed, cost-effectiveness and sensitivity. Therefore, pharmaceutical manufacturers would be advised to adopt PCR-based methods in the microbiological quality testing of pharmaceuticals in the future.

Advances Afoot in Microbiology

OpenAIRE

Patel, Robin; Karon, Brad S.

2017-01-01

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 Diagnost...

The eff ect of addition of selected vegetables on the microbiological, textural and fl avour profi le properties of yoghurts

OpenAIRE

Dorota Najgebauer-Lejko; Małgorzata Tabaszewska; Tadeusz Grega

2015-01-01

Background. Vegetables, apart from having high nutritional value, also contain considerable amounts of dietary fi bre and other components, which may affect physico-chemical properties of fermented milks, e.g. viscosity, texture, susceptibility to syneresis, fl avour profi le etc. The present work was established to study the effect of selected vegetables addition on the rheological, textural, microbiological and fl avour profi le parameters of yoghurts. Material and methods. The vegetabl...

Characterisation of gaharu hydrosol: Physical, chemical and microbiological properties

International Nuclear Information System (INIS)

Nur Humaira Lau Abdullah; Salmah Moosa

2010-01-01

Gaharu hydrosol is produced during the hydro distillation of resinous wood part of Aquilaria sp. This aromatic water is being considered as a by-product in the industry. There is interest to turn this aromatic by-product into aroma therapy products. The present study is carried out in order to understand the properties of gaharu hydrosol, physically, chemically and microbiologically. Gaharu hydrosol from two different extraction facilities for example at Kedaik Agar wood Sdn. Bhd. and Malaysian Nuclear Agency were characterised in this study. All the gaharu hydrosol samples displayed acidic nature, with pH in the range of 3.62 - 4.53. Four antioxidant assays were carried out to ascertain the antioxidant capabilities of two gaharu hydrosol samples through the total phenolic content assay, ABTS + radical scavenging activity, DPPH· radical scavenging activity and ferric reducing activity (FRAP). The results revealed that the samples exhibited lower antioxidant capabilities as compared to the positive control. For microbial population study, fungi was not present in the samples as there was no growth observed on the Plate Sabouraud Dextrose Agar (SDA) using membrane filtration technique. The antibacterial activity of the gaharu hydrosol against Staphylococcus aureus and Pseudomonas aeruginosa was determined using agar dilution method and disk diffusion method. The results showed that the gaharu hydrosol did not inhibit the growth of both the bacteria. The results obtained from this study will be further evaluated for the development of new products using this aromatic gaharu by-product. (author)

Standardization of PCR technique for detecting Listeria monocytogenes in chicken, beef and pork/Estandarización de la técnica PCR para diagnosticar Listeria monocytogenes en carne de pollo, res y cerdo

Directory of Open Access Journals (Sweden)

Asael E. de la Rosa-Zariñana

2018-01-01

Full Text Available The aim of this study was to standardize the PCR technique for detecting Listeria monocytogenes (Lm in chicken, beef and pork. The sensitivity and speci city of PCR and the level of concordance with the microbiological method were evaluated. PCR was standardized using a total of 60 samples of chicken, beef and pork (20 samples per meat type. Sensitivity and speci city were calculated using the 2 x 2 table and the level of accordance by the Kappa index. The minimum detectable DNA concentration was 3.0 ng μL−1. The PCR showed 100% sensitivity and speci city, and 80, 91 and 100% concordance between the methods was obtained for detecting Lm in chicken, beef and pork samples respectively, with 89.4% similarity between the methods for the three types of meat.

Clinical microbiology informatics.

Science.gov (United States)

Rhoads, Daniel D; Sintchenko, Vitali; Rauch, Carol A; Pantanowitz, Liron

2014-10-01

The clinical microbiology laboratory has responsibilities ranging from characterizing the causative agent in a patient's infection to helping detect global disease outbreaks. All of these processes are increasingly becoming partnered more intimately with informatics. Effective application of informatics tools can increase the accuracy, timeliness, and completeness of microbiology testing while decreasing the laboratory workload, which can lead to optimized laboratory workflow and decreased costs. Informatics is poised to be increasingly relevant in clinical microbiology, with the advent of total laboratory automation, complex instrument interfaces, electronic health records, clinical decision support tools, and the clinical implementation of microbial genome sequencing. This review discusses the diverse informatics aspects that are relevant to the clinical microbiology laboratory, including the following: the microbiology laboratory information system, decision support tools, expert systems, instrument interfaces, total laboratory automation, telemicrobiology, automated image analysis, nucleic acid sequence databases, electronic reporting of infectious agents to public health agencies, and disease outbreak surveillance. The breadth and utility of informatics tools used in clinical microbiology have made them indispensable to contemporary clinical and laboratory practice. Continued advances in technology and development of these informatics tools will further improve patient and public health care in the future. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

MPprimer: a program for reliable multiplex PCR primer design

Directory of Open Access Journals (Sweden)

Wang Xiaolei

2010-03-01

Full Text Available Abstract Background Multiplex PCR, defined as the simultaneous amplification of multiple regions of a DNA template or multiple DNA templates using more than one primer set (comprising a forward primer and a reverse primer in one tube, has been widely used in diagnostic applications of clinical and environmental microbiology studies. However, primer design for multiplex PCR is still a challenging problem and several factors need to be considered. These problems include mis-priming due to nonspecific binding to non-target DNA templates, primer dimerization, and the inability to separate and purify DNA amplicons with similar electrophoretic mobility. Results A program named MPprimer was developed to help users for reliable multiplex PCR primer design. It employs the widely used primer design program Primer3 and the primer specificity evaluation program MFEprimer to design and evaluate the candidate primers based on genomic or transcript DNA database, followed by careful examination to avoid primer dimerization. The graph-expanding algorithm derived from the greedy algorithm was used to determine the optimal primer set combinations (PSCs for multiplex PCR assay. In addition, MPprimer provides a virtual electrophotogram to help users choose the best PSC. The experimental validation from 2× to 5× plex PCR demonstrates the reliability of MPprimer. As another example, MPprimer is able to design the multiplex PCR primers for DMD (dystrophin gene which caused Duchenne Muscular Dystrophy, which has 79 exons, for 20×, 20×, 20×, 14×, and 5× plex PCR reactions in five tubes to detect underlying exon deletions. Conclusions MPprimer is a valuable tool for designing specific, non-dimerizing primer set combinations with constrained amplicons size for multiplex PCR assays.

Multiplex PCR assay for simultaneous detection of six major bacterial pathogens of rice.

Science.gov (United States)

Cui, Z; Ojaghian, M R; Tao, Z; Kakar, K U; Zeng, J; Zhao, W; Duan, Y; Vera Cruz, C M; Li, B; Zhu, B; Xie, G

2016-05-01

The aim of this study was to develop a multiplex PCR (mPCR) assay for rapid, sensitive and simultaneous detection of six important rice pathogens: Xanthomonas oryzae pv. oryzae, X. oryzae pv. oryzicola, Pseudomonas fuscovaginae, Burkholderia glumae, Burkholderia gladioli and Acidovorax avenae subsp. avenae. Specific primers were designed through a bioinformatics pipeline. Sensitivity of detection was established using both traditional PCR and quantitative real-time PCR on isolated DNA and on bacterial cells both in vitro and in simulated diseased seeds and the parameters were optimized for an mPCR assay. A total of 150 bacterial strains were tested for specificity. The mPCR assay accurately predicted the presence of pathogens among 44 symptomatic and asymptomatic rice seed, sheath and leaf samples. This study confirmed that this mPCR assay is a rapid, reliable and simple tool for the simultaneous detection of six important rice bacterial pathogens. This study is the first report of a method allowing simultaneous detection of six major rice pathogens. The ability to use crude extracts from plants without bacterial isolation or DNA extraction enhances the value of this mPCR technology for rapid detection and aetiological/epidemiological studies. © 2016 The Society for Applied Microbiology.

Development of lotus root fermented sugar syrup as a functional food supplement/condiment and evaluation of its physicochemical, nutritional and microbiological properties.

Science.gov (United States)

Shukla, Shruti; Park, Juyeon; Park, Jung Hyun; Lee, Jong Suk; Kim, Myunghee

2018-02-01

Lotus ( Nelumbo nucifera ) root has been used as an edible vegetable in East Asia for thousands of years. The present research was aimed to explore the physicochemical, nutritional and microbiological safety of lotus root fermented sugar syrup as a fermented food supplement or condiment for human health benefits. In this study, the physicochemical, nutritional and microbiological safety properties of lotus root syrup fermented with 57° Brix brown sugar at different time periods until 6 months (180 days) was investigated. There was a significant improvement as compared to 57° Brix brown sugar broth (as a control) in the total acceptability and physicochemical properties of lotus root sugar syrup samples such as pH and color improvement. The red color values of 180 days lotus root fermented sugar syrup samples were significantly enhanced (6.85 ± 0.58) when compared with the control (0.20 ± 0.15). In addition, the total protein content was increased from 8.27 ± 0.86 to 392.33 ± 7.19 μg/mL, along with the increase in fermentation time reaching to the level of consumption acceptability. All the lotus root fermented sugar syrup samples were subjected to microbiological analysis. It was found that the coliform, Bacillus cereus , Escherichia coli , Salmonella and Staphylococcus aureus counts were not detected in majority of the samples, confirming the high degree of hygiene processing of lotus root fermented sugar syrup samples for its use as a food supplement or condiment.

Microbiological Standardization in Small Laboratory Animals and Recommendations for the Monitoring

Directory of Open Access Journals (Sweden)

Meral Karaman

2014-03-01

Full Text Available Microbiological standardization in laboratory animal breeding is based on the classification according to the microorganisms that the animals host and consequently their upbringing environment, as well as the certification of their microbiological status and the protection of their properties. Although there are many different classifications for microbiological standardization of laboratory animals, they can be basically classified as; gnotobiotic animals, animals bred with a complete barrier system (Germ free, GF, with Colonization-Resistant Flora; CRF, animals bred with a partial barrier system (Specified Pathogen Free, SPF, and animals bred by conventional methods in units without barriers (Conventional; CV. Monitoring of microbiological standardization is carried out in two ways. One is controlling barrier systems (process control and the other is controlling laboratory animals (product control. In controlling barrier systems samples are taken routinely from ambient air, surfaces, base plate materials of animals, foods and waters, and microbiological tests are carried out. FELASA guidelines are frequently used in monitoring laboratory animals. These guidelines where the monitoring frequency, sample size, micro-organisms to be tested, vary according to the microbiological quality of the animals, and test methods and are frequently updated by FELASA and shared in their web pages. In our country, in general, laboratory animals used for experimental studies present no microbiological standardization, and follow-up protocols are not implemented. Therefore, construction of facilities for the production of microbiologically standard animals and establishment of backup laboratories testing microbiological quality should be established.

CHEMICAL AND MICROBIOLOGICAL ATTRIBUTES UNDER DIFFERENT SOIL COVER

Directory of Open Access Journals (Sweden)

Elaine Novak

2017-03-01

Full Text Available A challenge for the environmental recovery of degraded areas is the search for soil data. In this process, the microbiological parameters and soil chemicals are potential indicators of soil quality. This study aimed to evaluate soil quality based on microbiological and chemical soil attributes in different areas involving environmental recovery, sugarcane cultivation and remnants of native vegetation located in a rural private property farm in State of Mato Grosso do Sul, Brazil, in Hapludox Eutrophic soil. The microbiological (microbial biomass carbon, basal respiration, microbial quotient and metabolic quotient and chemical parameters (organic matter, carbon, pH, cationic exchange capacity, sum of bases, potassium, phosphorus, magnesium, calcium, saturation base and potential acidity were assessed. Data were assessed by variance and multivariate analysis (Principal Component Analysis and cluster analysis. Overall, the results showed highest alteration in the chemical and microbiological characteristics of the soil in sugarcane cultivation area in comparison with other areas. Considering the studied recovery areas, REC1, REC5 and REC7 show chemical and microbiological conditions with most similarity to native vegetation. Despite the short period of the resilience enhancement of environmental recovery areas, the development of vegetation cover and establishment of the microbial community were determined to be important factors for improving soil quality and environmental recovery in several of the areas studied.

Comparative, Collaborative, and On-Site Validation of a TaqMan PCR Method as a Tool for Certified Production of Fresh, Campylobacter-Free Chickens

DEFF Research Database (Denmark)

Krause, Michael; Josefsen, Mathilde Hartmann; Lund, Marianne

2006-01-01

, a faster, real-time PCR approach was validated in comparative and collaborative trials, based on recommendations from the Nordic system for validation of alternative microbiological methods (NordVal). The comparative real-time PCR trial was performed in comparison to two reference culture protocols...... fulfilled the NordVal validation criteria and has since been implemented at a major abattoir....

Physico-chemical, sensory and microbiological qualities of yoghurt ...

African Journals Online (AJOL)

This study was conducted to evaluate the physico-chemical, sensory and microbiological qualities of some yoghurt brands sold in Kano Metropolis using standard procedures. The physico-chemical characteristics (viscosity, specific gravity, pH, titratable acidity, fat content) and Sensory properties (color, flavor, smell) were ...

[Clinical microbiology laboratory and imported parasitic diseases].

Science.gov (United States)

Martín-Rabadán, Pablo; Martínez-Ruiz, Rocío; Cuadros, Juan; Cañavate, Carmen

2010-12-01

Imported parasitosis represents an increasingly frequent diagnostic challenge for microbiology laboratories. A surge in immigration and international travel has led to a rise in the number of imported cases of parasitosis, and this trend is expected to continue in the future. The present article addresses this challenge by reviewing recommended diagnostic approaches and tests. Currently, microscopy is always recommended when analysing blood samples for parasites. If malaria is suspected, rapid antigen testing (including at least HRP2 antigen) should also be performed. The work-up for suspected leishmaniasis should include serology, culture, and in selected cases detection of antigen in urine. In suspected Chagas disease, two different serological tests should be performed. PCR for blood protozoa is highly sensitive, although it cannot be used to rule out Chagas disease, since this condition may be present without parasitemia. Accurate diagnosis of intestinal amebiasis usually requires PCR or antigen detection tests. In helminthiasis, traditional microscopy may need to be complemented with other tests, such as agar plate culture for strongyloidiasis, Og4C3 antigen detection for bancroftian filariasis, and antibody detection test for filariasis and schistosomiasis. Copyright © 2010 Elsevier España, S.L. All rights reserved.

[Microbiology--laboratory examinations for bacterias].

Science.gov (United States)

Hen, Renjun; Imafuku, Yuji; Yoshida, Hiroshi

2002-11-01

As it has been required to identify pathogenic microbes in shorter times, simple and rapid methods have been developed and used. Here, we summarized the present situation of rapid diagnostic testing in clinical microbiology in Japan, and also presented our results on PBP2' detection. The rapid test kits available in Japan for E. coli, Helicobacter pylori, Salmonella, Streptococcus and Staphylococcus aureus were described. Rapid examination methods are based mainly on immunologic reactions, which included slide agglutination using latex particle, immunochromatography and ELISA. Times required for the identification are 10 to 15 minutes. Moreover, rapid test kits employing PCR are also marketed. Further, we evaluated MRSA-LA "Seiken" which is a rapid detection kit for PBP2' produced by MRSA. The test was shown to be highly sensitive and specific. For the rapid identification of pathogenic microbes, simple and rapid test kits described here will be used more in clinical diagnosis.

[Environmental microbiological control].

Science.gov (United States)

Martín Salas, Carmen; Tordoya Titichoca, Igberto J; Ezpeleta Baquedano, Carmen

2016-07-01

The environmental microbiological control is necessary to prevent infections associated with certain procedures that are performed at the hospital. In this review the procedures for control of water and dialysis fluids, and air in operating rooms and immunocompromised units are addressed. The dialysis quality management guidelines define the highest levels of chemical, microbiological and endotoxin in purified water and dialysis fluids based on the recommendations of scientific societies. The microbiological control of water and dialysis fluids should include detection of microorganisms and endotoxin levels. Regarding the microbiological air sampling of operating rooms and immunocompromised units the types of clean rooms in which is recommended to perform microbiological air monitoring; the sample collection methods; culture media; incubation conditions; the most common microorganisms, and permissible levels depending on the type of surgery are described. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

Salty Microbiology

Science.gov (United States)

Schneegurt, Mark A.; Wedel, Adrianne N.; Pokorski, Edward W.

2004-01-01

Using microbiology activities in the classroom is an effective way for teachers to address National Standards in the life sciences. However, common microbiology activities that involve swabbing doorknobs and hands are too risky due to the likelihood of culturing human pathogens. In addition, making sterile media and maintaining sterile conditions…

Use of Multiplex Real-Time PCR To Diagnose Scrub Typhus.

Science.gov (United States)

Tantibhedhyangkul, Wiwit; Wongsawat, Ekkarat; Silpasakorn, Saowaluk; Waywa, Duangdao; Saenyasiri, Nuttawut; Suesuay, Jintapa; Thipmontree, Wilawan; Suputtamongkol, Yupin

2017-05-01

Scrub typhus, caused by Orientia tsutsugamushi , is a common cause of acute undifferentiated febrile illness in the Asia-Pacific region. However, its nonspecific clinical manifestation often prevents early diagnosis. We propose the use of PCR and serologic tests as diagnostic tools. Here, we developed a multiplex real-time PCR assay using hydrolysis (TaqMan) probes targeting O. tsutsugamushi 47-kDa, groEL , and human interferon beta (IFN-β gene) genes to improve early diagnosis of scrub typhus. The amplification efficiency was higher than 94%, and the lower detection limit was 10 copies per reaction. We used a human gene as an internal DNA quality and quantity control. To determine the sensitivity of this PCR assay, we selected patients with confirmed scrub typhus who exhibited a clear 4-fold increase in the level of IgG and/or IgM. The PCR assay result was positive in 45 of 52 patients, indicating a sensitivity of 86.5% (95% confidence interval [CI]: 74.2 to 94.4). The PCR assessment was negative for all 136 non-scrub typhus patients, indicating a specificity of 100% (95% CI: 97.3 to 100). In addition, this test helped diagnose patients with inconclusive immunofluorescence assay (IFA) results and using single blood samples. In conclusion, the real-time PCR assay proposed here is sensitive and specific in diagnosing scrub typhus. Combining PCR and serologic tests will improve the diagnosis of scrub typhus among patients presenting with acute febrile illness. Copyright © 2017 American Society for Microbiology.

Effect of apple pectin on gut microbiota - qPCR in applied microbiology

DEFF Research Database (Denmark)

Bergström, Anders; Wilcks, Andrea; Poulsen, Morten

This study was part of the large European project ISAFRUIT aiming to reveal the biological explanations for the epidemiologically well-established health effects of fruits. The objective was to identify effects of apple and apple product consumption on the composition of the cecal microbial...... community in rats, as well as on a number of cecal parameters, which could be influenced by a changed microbiota. Principal Component Analysis (PCA) of cecal microbiota profiles obtained by PCR-DGGE targeting bacterial 16S rRNA genes showed an effect of whole apples in a long-term feeding study (14 weeks...

Assessment of the real-time PCR and different digital PCR platforms for DNA quantification.

Science.gov (United States)

Pavšič, Jernej; Žel, Jana; Milavec, Mojca

2016-01-01

Digital PCR (dPCR) is beginning to supersede real-time PCR (qPCR) for quantification of nucleic acids in many different applications. Several analytical properties of the two most commonly used dPCR platforms, namely the QX100 system (Bio-Rad) and the 12.765 array of the Biomark system (Fluidigm), have already been evaluated and compared with those of qPCR. However, to the best of our knowledge, direct comparison between the three of these platforms using the same DNA material has not been done, and the 37 K array on the Biomark system has also not been evaluated in terms of linearity, analytical sensitivity and limit of quantification. Here, a first assessment of qPCR, the QX100 system and both arrays of the Biomark system was performed with plasmid and genomic DNA from human cytomegalovirus. With use of PCR components that alter the efficiency of qPCR, each dPCR platform demonstrated consistent copy-number estimations, which indicates the high resilience of dPCR. Two approaches, one considering the total reaction volume and the other considering the effective reaction size, were used to assess linearity, analytical sensitivity and variability. When the total reaction volume was considered, the best performance was observed with qPCR, followed by the QX100 system and the Biomark system. In contrast, when the effective reaction size was considered, all three platforms showed almost equal limits of detection and variability. Although dPCR might not always be more appropriate than qPCR for quantification of low copy numbers, dPCR is a suitable method for robust and reproducible quantification of viral DNA, and a promising technology for the higher-order reference measurement method.

PCR+ In Diesel Fuels and Emissions Research

Energy Technology Data Exchange (ETDEWEB)

McAdams, H.T.

2002-04-15

In past work for the U.S. Department of Energy (DOE) and Oak Ridge National Laboratory (ORNL), PCR+ was developed as an alternative methodology for building statistical models. PCR+ is an extension of Principal Components Regression (PCR), in which the eigenvectors resulting from Principal Components Analysis (PCA) are used as predictor variables in regression analysis. The work was motivated by the observation that most heavy-duty diesel (HDD) engine research was conducted with test fuels that had been ''concocted'' in the laboratory to vary selected fuel properties in isolation from each other. This approach departs markedly from the real world, where the reformulation of diesel fuels for almost any purpose leads to changes in a number of interrelated properties. In this work, we present new information regarding the problems encountered in the conventional approach to model-building and how the PCR+ method can be used to improve research on the relationship between fuel characteristics and engine emissions. We also discuss how PCR+ can be applied to a variety of other research problems related to diesel fuels.

Immuno-PCR, a new technique for the serodiagnosis of tuberculosis.

Science.gov (United States)

Mehta, Promod K; Dahiya, Bhawna; Sharma, Suman; Singh, Netrapal; Dharra, Renu; Thakur, Zoozeal; Mehta, Neeru; Gupta, Krishna B; Gupta, Mahesh C; Chaudhary, Dhruva

2017-08-01

Rapid and accurate diagnosis of tuberculosis (TB) is essential to control the disease. The conventional microbiological tests have limitations and there is an urgent need to devise a simple, rapid and reliable point-of-care (POC) test. The failure of TB diagnostic tests based on antibody detection due to inconsistent and imprecise results has stimulated renewed interest in the development of rapid antigen detection methods. However, the World Health Organization (WHO) has emphasized to continue research for designing new antibody-based detection tests with improved accuracy. Immuno-polymerase chain reaction (I-PCR) combines the simplicity and versatility of enzyme-linked immunosorbent assay (ELISA) with the exponential amplification capacity and sensitivity of PCR thus leading to several-fold increase in sensitivity in comparison to analogous ELISA. In this review, we have described the serodiagnostic potential of I-PCR assays for an early diagnosis of TB based on the detection of potential mycobacterial antigens and circulating antibodies in body fluids of TB patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Aquatic Microbiology Laboratory Manual.

Science.gov (United States)

Cooper, Robert C.; And Others

This laboratory manual presents information and techniques dealing with aquatic microbiology as it relates to environmental health science, sanitary engineering, and environmental microbiology. The contents are divided into three categories: (1) ecological and physiological considerations; (2) public health aspects; and (3)microbiology of water…

Microbiological Efficacy Test Methods of Disinfectants

OpenAIRE

Şahiner, Aslı

2015-01-01

Disinfection process is required in every area where microbiological contamination and infection risk is present, especially in medical sector, food, veterinary and general common living areas hence many disinfectants and antiseptics are being produced for different purposes. Disinfectants are made up a large group of biocidal products. Depending on the chemical properties of active substances, targeted microorganisms may differ While some disinfectants are effective in a large spectrum, othe...

Clinical Assessment of a Nocardia PCR-Based Assay for Diagnosis of Nocardiosis.

Science.gov (United States)

Rouzaud, Claire; Rodriguez-Nava, Véronica; Catherinot, Emilie; Méchaï, Frédéric; Bergeron, Emmanuelle; Farfour, Eric; Scemla, Anne; Poirée, Sylvain; Delavaud, Christophe; Mathieu, Daniel; Durupt, Stéphane; Larosa, Fabrice; Lengelé, Jean-Philippe; Christophe, Jean-Louis; Suarez, Felipe; Lortholary, Olivier; Lebeaux, David

2018-06-01

The diagnosis of nocardiosis, a severe opportunistic infection, is challenging. We assessed the specificity and sensitivity of a 16S rRNA Nocardia PCR-based assay performed on clinical samples. In this multicenter study (January 2014 to April 2015), patients who were admitted to three hospitals and had an underlying condition favoring nocardiosis, clinical and radiological signs consistent with nocardiosis, and a Nocardia PCR assay result for a clinical sample were included. Patients were classified as negative control (NC) (negative Nocardia culture results and proven alternative diagnosis or improvement at 6 months without anti- Nocardia treatment), positive control (PC) (positive Nocardia culture results), or probable nocardiosis (positive Nocardia PCR results, negative Nocardia culture results, and no alternative diagnosis). Sixty-eight patients were included; 47 were classified as NC, 8 as PC, and 13 as probable nocardiosis. PCR results were negative for 35/47 NC patients (74%). For the 12 NC patients with positive PCR results, the PCR assay had been performed with respiratory samples. These NC patients had chronic bronchopulmonary disease more frequently than did the NC patients with negative PCR results (8/12 patients [67%] versus 11/35 patients [31%]; P = 0.044). PCR results were positive for 7/8 PC patients (88%). There were 13 cases of probable nocardiosis, diagnosed solely using the PCR results; 9 of those patients (69%) had lung involvement (consolidation or nodule). Nocardia PCR testing had a specificity of 74% and a sensitivity of 88% for the diagnosis of nocardiosis. Nocardia PCR testing may be helpful for the diagnosis of nocardiosis in immunocompromised patients but interpretation of PCR results from respiratory samples is difficult, because the PCR assay may also detect colonization. Copyright © 2018 American Society for Microbiology.

A Real-Time PCR Detection of Genus Salmonella in Meat and Milk Samples

Directory of Open Access Journals (Sweden)

Jaroslav Pochop

2013-05-01

Full Text Available The aim of this study was follow the contamination of ready to eat milk and meat products with Salmonella spp. by using the Step One real-time PCR. Classical microbiological methods for detection of food-borne bacteria involve the use of pre-enrichment and/or specific enrichment, followed by the isolation of the bacteria in solid media and a final confirmation by biochemical and/or serological tests. We used the PrepSEQ Rapid Spin Sample Preparation Kit for isolation of DNA and SensiFAST SYBR Hi-ROX Kit for the real-time PCR performance. In the investigated samples without incubation we could detect strain of Salmonella sp. in five out of twenty three samples (swabs. This Step One real-time PCR assay is extremely useful for any laboratory in possession of a real-time PCR. It is a fast, reproducible, simple, specific and sensitive way to detect nucleic acids, which could be used in clinical diagnostic tests in the future. Our results indicated that the Step One real-time PCR assay developed in this study could sensitively detect Salmonella spp. in ready to eat food.

Development of quantitative real-time PCR for detection and enumeration of Enterobacteriaceae.

Science.gov (United States)

Takahashi, Hajime; Saito, Rumi; Miya, Satoko; Tanaka, Yuichiro; Miyamura, Natsumi; Kuda, Takashi; Kimura, Bon

2017-04-04

The family Enterobacteriaceae, members of which are widely distributed in the environment, includes many important human pathogens. In this study, a rapid real-time PCR method targeting rplP, coding for L16 protein, a component of the ribosome large subunit, was developed for enumerating Enterobacteriaceae strains, and its efficiency was evaluated using naturally contaminated food products. The rplP-targeted real-time PCR amplified Enterobacteriaceae species with Ct values of 14.0-22.8, whereas the Ct values for non-Enterobacteriaceae species were >30, indicating the specificity of this method for the Enterobacteriaceae. Using a calibration curve of Ct=-3.025 (log CFU/g)+37.35, which was calculated from individual plots of the cell numbers in different concentrations of 5 Enterobacteriaceae species, the rplP-targeted real-time PCR was applied to 51 food samples. A Enterobacteriaceae species in foods rapidly and accurately, and therefore, it can be used for the microbiological risk analysis of foods. Copyright © 2017 Elsevier B.V. All rights reserved.

Phosphorus Mobility in the Landscape: First Steps to Linking Hydrology and Microbiology

Science.gov (United States)

Saia, S. M.; Walter, M. T.; Regan, J.

2011-12-01

Numerous resources are spent each year to control phosphorus (P) nonpoint source pollution around the world. Despite these efforts, high P levels in freshwater bodies are still a persistent issue. Eutrophication and subsequent algal bloom die-offs, brought about by excess P, can harm local economies as well as human and ecosystem health. To overcome this disconnect between nutrient management strategies and observed P concentrations, scientists must advance research beyond the physical and chemical mechanisms commonly included in P transport experiments. Microbiological techniques (e.g. PCR and flow cytometry) are making it easier to tease out the influence of specific microorganisms on nutrient transport. Polyphosphate accumulating organisms (PAOs) are often used in wastewater treatment plants (WWTP) to remove P from effluent water but have rarely been studied in natural settings. In this study, we combined field and laboratory column experiments to identifying the influence of changing water content and temperature on PAO-facilitated P mobility. In the field, we collected a gridded network of soil samples and measured the temperature, water content, and P concentrations (bioavailable and total P) for each. We also quantified PAO presence using qPCR techniques. In the lab, we added various concentrations of WWTP sludge (with PAO present) to autoclaved soils. We measured dissolved P concentrations in effluent water with respect to moisture content and temperature. Based on the results to these experiments, we hope to draw attention to the importance of microbiological controls on P mobility in freshwater ecosystems.

Utility of PCR, Culture, and Antigen Detection Methods for Diagnosis of Legionellosis.

Science.gov (United States)

Chen, Derrick J; Procop, Gary W; Vogel, Sherilynn; Yen-Lieberman, Belinda; Richter, Sandra S

2015-11-01

The goal of this retrospective study was to evaluate the performance of different diagnostic tests for Legionnaires' disease in a clinical setting where Legionella pneumophila PCR had been introduced. Electronic medical records at the Cleveland Clinic were searched for Legionella urinary antigen (UAG), culture, and PCR tests ordered from March 2010 through December 2013. For cases where two or more test methods were performed and at least one was positive, the medical record was reviewed for relevant clinical and epidemiologic factors. Excluding repeat testing on a given patient, 19,912 tests were ordered (12,569 UAG, 3,747 cultures, and 3,596 PCR) with 378 positive results. The positivity rate for each method was 0.4% for culture, 0.8% for PCR, and 2.7% for UAG. For 37 patients, at least two test methods were performed with at least one positive result: 10 (27%) cases were positive by all three methods, 16 (43%) were positive by two methods, and 11 (30%) were positive by one method only. For the 32 patients with medical records available, clinical presentation was consistent with proven or probable Legionella infection in 84% of the cases. For those cases, the sensitivities of culture, PCR, and UAG were 50%, 92%, and 96%, respectively. The specificities were 100% for culture and 99.9% for PCR and UAG. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Microbiological corrosion of metals

International Nuclear Information System (INIS)

Vladislavlev, V.V.

1992-01-01

Problems is considered of development of the microbiological corrosion of the NPP equipment. The main attention is paid to the selective character of microbiological corrosion in zones of welded joints of austenitic steels. It is noted that the presence of technological defects promotes growth of corrosional damages. Methods for microbiological corrosion protection are discussed

Validation of an open-formula, diagnostic real-time PCR method for 20-hr detection of Salmonella in animal feeds

DEFF Research Database (Denmark)

Löfström, Charlotta; Hoorfar, Jeffrey

2012-01-01

A comparative study of a 20-hr, non-commercial, open-formula PCR method and the standard culture-based method NMKL 187, for detection of Salmonella, was performed according to the validation protocol from the Nordic organization for validation of alternative microbiological methods (NordVal) on 81...

Automation in Clinical Microbiology

Science.gov (United States)

Ledeboer, Nathan A.

2013-01-01

Historically, the trend toward automation in clinical pathology laboratories has largely bypassed the clinical microbiology laboratory. In this article, we review the historical impediments to automation in the microbiology laboratory and offer insight into the reasons why we believe that we are on the cusp of a dramatic change that will sweep a wave of automation into clinical microbiology laboratories. We review the currently available specimen-processing instruments as well as the total laboratory automation solutions. Lastly, we outline the types of studies that will need to be performed to fully assess the benefits of automation in microbiology laboratories. PMID:23515547

Improved metod of detection and molecular typing of Borrelia burgdorferi sensu lato in clinical sample by PCR without DNA purification

Czech Academy of Sciences Publication Activity Database

Rudenko, Natalia; Golovchenko, Maryna; Němec, J.; Volkaert, J.; Mallátová, N.; Grubhoffer, Libor

2005-01-01

Roč. 50, č. 1 (2005), s. 31-39 ISSN 0015-5632 R&D Projects: GA ČR GA524/03/1326 Institutional research plan: CEZ:AV0Z60220518 Keywords : PCR * chelex * amplification Subject RIV: EE - Microbiology, Virology Impact factor: 0.918, year: 2005

Evaluation of two real time PCR assays for the detection of bacterial DNA in amniotic fluid.

Science.gov (United States)

Girón de Velasco-Sada, Patricia; Falces-Romero, Iker; Quiles-Melero, Inmaculada; García-Perea, Adela; Mingorance, Jesús

2018-01-01

The aim of this study was to evaluate two non-commercial Real-Time PCR assays for the detection of microorganisms in amniotic fluid followed by identification by pyrosequencing. We collected 126 amniotic fluids from 2010 to 2015 for the evaluation of two Real-Time PCR assays for detection of bacterial DNA in amniotic fluid (16S Universal PCR and Ureaplasma spp. specific PCR). The method was developed in the Department of Microbiology of the University Hospital La Paz. Thirty-seven samples (29.3%) were positive by PCR/pyrosequencing and/or culture, 4 of them were mixed cultures with Ureaplasma urealyticum. The Universal 16S Real-Time PCR was compared with the standard culture (81.8% sensitivity, 97.4% specificity, 75% positive predictive value, 98% negative predictive value). The Ureaplasma spp. specific Real-Time PCR was compared with the Ureaplasma/Mycoplasma specific culture (92.3% sensitivity, 89.4% specificity, 50% positive predictive value, 99% negative predictive value) with statistically significant difference (p=0.005). Ureaplasma spp. PCR shows a rapid response time (5h from DNA extraction until pyrosequencing) when comparing with culture (48h). So, the response time of bacteriological diagnosis in suspected chorioamnionitis is reduced. Copyright © 2017 Elsevier B.V. All rights reserved.

Detection of Streptococcus pneumoniae in whole blood by PCR.

Science.gov (United States)

Zhang, Y; Isaacman, D J; Wadowsky, R M; Rydquist-White, J; Post, J C; Ehrlich, G D

1995-03-01

Streptococcus pneumoniae is a major cause of bacteremia in both children and adults. Currently, the diagnosis of pneumococcal bacteremia relies on the isolation and identification of the bacteria from blood cultures. We have developed a sensitive assay for the detection of S. pneumoniae in whole blood by the PCR. A specific primer-probe set (JM201 and JM202 primers with JM204 probe) designed from the penicillin-binding protein 2B gene was demonstrated to reproducibly detect between 10 and 100 fg of input purified S. pneumoniae DNA. This assay system was shown to be inclusive for all strains of S. pneumoniae evaluated, including 15 different serotypes and a battery of penicillin-resistant and -sensitive strains. The specificity of this PCR-based assay was demonstrated by its inability to support amplification from a series of human, bacterial, and yeast genomic DNAs. A general specimen preparation method which should be suitable for the purification of DNA from any pathogens in whole blood was developed. With this protocol it was possible to detect S. pneumoniae-specific DNA from whole blood specimens inoculated with as little as 4 CFU/ml. Copurified human blood DNA, ranging from 0 to 4.5 micrograms per PCR, did not affect the sensitivity of S. pneumoniae detection by PCR. A blinded clinical trial was used to compare the PCR-based assay with standard microbiological blood culture for the detection of S. pneumoniae bacteremia in 36 specimens obtained from pediatric patients seen in the emergency room of Children's Hospital of Pittsburgh. With culture as the "gold standard," the PCR-based assay had a sensitivity of 80% (4 of 5 culture-positive specimens were PCR positive) and a specificity of 84% (26 of 31 culture-negative specimens were PCR negative). However, three patients whose specimens were PCR positive and culture negative had histories suggestive of bacteremia, including recent positive blood cultures, treatment with antibiotics, cellulitis, and multiple

Effect of Oregano Essential Oil and Aqueous Oregano Infusion Application on Microbiological Properties of Samarella (Tsamarella), a Traditional Meat Product of Cyprus

OpenAIRE

Beyza Ulusoy; Canan Hecer; Doruk Kaynarca; Şifa Berkan

2018-01-01

Different types of dried meat products manufactured by different drying and curing methods are very common and well-known with a long history all over the world. Samarella (tsamarella) is one of these products and is famous among traditionally produced meat products in Cypriot gastronomy. The aim of this study was to investigate the effect of oregano essential oil (OEO) and aqueous oregano infusion (AOI) applications on the microbiological properties of samarella. In order to carry out this s...

Food safety assurance systems: Microbiological testing, sampling plans, and microbiological criteria

NARCIS (Netherlands)

Zwietering, M.H.; Ross, T.; Gorris, L.G.M.

2014-01-01

Microbiological criteria give information about the quality or safety of foods. A key component of a microbiological criterion is the sampling plan. Considering: (1) the generally low level of pathogens that are deemed tolerable in foods, (2) large batch sizes, and (3) potentially substantial

Escherichia coli H-Genotyping PCR: a Complete and Practical Platform for Molecular H Typing.

Science.gov (United States)

Banjo, Masaya; Iguchi, Atsushi; Seto, Kazuko; Kikuchi, Taisei; Harada, Tetsuya; Scheutz, Flemming; Iyoda, Sunao

2018-06-01

In Escherichia coli , more than 180 O groups and 53 H types have been recognized. The O:H serotyping of E. coli strains is an effective method for identifying strains with pathogenic potential and classifying them into clonal groups. In particular, the serotyping of Shiga toxin-producing E. coli (STEC) strains provides valuable information to evaluate the routes, sources, and prevalence of agents in outbreak investigations and surveillance. Here, we present a complete and practical PCR-based H-typing system, E. coli H-genotyping PCR, consisting of 10 multiplex PCR kits with 51 single PCR primer pairs. Primers were designed based on a detailed comparative analysis of sequences from all H-antigen (flagellin)-encoding genes, fliC and its homologs. The specificity of this system was confirmed by using all H type reference strains. Additionally, 362 serotyped wild strains were also used to evaluate its practicality. All 277 H-type-identified isolates gave PCR products that corresponded to the results of serological H typing. Moreover, 76 nonmotile and nine untypeable strains could be successfully subtyped into any H type by the PCR system. The E. coli H-genotyping PCR developed here allows broader, rapid, and low-cost subtyping of H types and will assist epidemiological studies as well as surveillance of pathogenic E. coli . Copyright © 2018 American Society for Microbiology.

Validation of a same-day real-time PCR method for screening of meat and carcass swabs for Salmonella

DEFF Research Database (Denmark)

Löfström, Charlotta; Krause, Michael; Josefsen, Mathilde Hartmann

2009-01-01

of the published PCR methods for Salmonella have been validated in collaborative studies. This study describes a validation including comparative and collaborative trials, based on the recommendations from the Nordic organization for validation of alternative microbiological methods (NordVal) of a same-day, non....... Partly based on results obtained in this study, the method has obtained NordVal approval for analysis of Salmonella in meat and carcass swabs. The PCR method was transferred to a production laboratory and the performance was compared with the BAX Salmonella test on 39 pork samples artificially...... contaminated with Salmonella. There was no significant difference in the results obtained by the two methods. Conclusion: The real-time PCR method for detection of Salmonella in meat and carcass swabs was validated in comparative and collaborative trials according to NordVal recommendations. The PCR method...

Retrospective Review of Treponema pallidum PCR and Serology Results: Are Both Tests Necessary?

Science.gov (United States)

Brischetto, Anna; Gassiep, Ian; Whiley, David; Norton, Robert

2018-05-01

There has been a resurgence of syphilis diagnoses in Australia. We investigated whether our Treponema pallidum PCR test provides any additional diagnostic information over syphilis serology (chemiluminescence immunoassay [CMIA], Treponema pallidum particle agglutination [TPPA] assay, and the rapid plasma reagin [RPR] flocculation test). A retrospective audit of all T. pallidum PCR requests that came through our laboratory from January 2010 to June 2017 was conducted; data collected included age, gender, site of swab, and results from T. pallidum PCR, syphilis serology, and herpes simplex virus 1 (HSV-1) and HSV-2 PCRs. A total of 441 T. pallidum PCR tests were performed; on average, 3 T. pallidum PCRs per month were requested in 2011, and this rate increased to 17.2 requests per month in 2017. A total of 323 patients had both T. pallidum PCR and syphilis serology performed, with 67% of swabs taken from the genitals. T. pallidum PCR gave positive results for 61/323 (19%) patients; of these 61 patients, 59 (97%) also had positive syphilis serology results ( T. pallidum PCR sensitivity, 68%; specificity, 99%; positive predictive value, 97%; negative predictive value, 89%). Syphilis serology was positive for 91/323 patients (28%); of these 91 patients, 61 (66%) were also T. pallidum PCR positive (syphilis serology sensitivity, 97%; specificity, 88%; positive predictive value, 60%; negative predictive value, 99%). The Cohen's kappa value was 0.74, indicating substantial agreement between the two tests. Our results show that most patients with positive T. pallidum PCR results also had positive syphilis serology. Therefore, T. pallidum PCR adds little clinical value over serology for the diagnosis of syphilis in certain clinical settings. Copyright © 2018 American Society for Microbiology.

Microbiological Monitoring in Geothermal Plants

Science.gov (United States)

Alawi, M.; Lerm, S.; Linder, R.; Vetter, A.; Vieth-Hillebrand, A.; Miethling-Graff, R.; Seibt, A.; Wolfgramm, M.; Wuerdemann, H.

2010-12-01

In the scope of the research projects “AquiScreen” and “MiProTherm” we investigated geothermally used groundwater systems under microbial, geochemical, mineralogical and petrological aspects. On one side an enhanced process understanding of engineered geothermal systems is mandatory to optimize plant reliability and economy, on the other side this study provides insights into the microbiology of terrestrial thermal systems. Geothermal systems located in the North German Basin and the Molasse Basin were analyzed by sampling of fluids and solid phases. The investigated sites were characterized by different temperatures, salinities and potential microbial substrates. The microbial population was monitored by the use of genetic fingerprinting techniques and PCR-cloning based on PCR-amplified 16S rRNA and dissimilatory sulfite reductase (DSR) genes. DNA-sequences of fingerprints and cloned PCR-products were compared to public databases and correlated with metabolic classes to provide information about the biogeochemical processes. In all investigated geothermal plants, covering a temperature range from 5° to 120°C, microorganisms were found. Phylogenetic gene analyses indicate a broad diversity of microorganisms adapted to the specific conditions in the engineered system. Beside characterized bacteria like Thermus scotoductus, Siderooxidans lithoautotrophicus and the archaeon Methanothermobacter thermoautotrophicus a high number of so far uncultivated microorganisms was detected. As it is known that - in addition to abiotic factors - microbes like sulfate-reducing bacteria (SRB) are involved in the processes of corrosion and scaling in plant components, we identified SRB by specific analyses of DSR genes. The SRB detected are closely related to thermotolerant and thermophilic species of Desulfotomaculum, Thermodesulfovibrio, Desulfohalobium and Thermodesulfobacterium, respectively. Overall, the detection of microbes known to be involved in biocorrosion and the

[Onsite microbiology services and outsourcing microbiology and offsite laboratories--advantage and disadvantage, thinking of effective utilization].

Science.gov (United States)

Hosokawa, Naoto

2011-10-01

In recent years, budget restrictions have prompted hospital managers to consider outsourcing microbiology service. But there are many advantages onsite microbiology services. Onsite microbiology services have some advantages. 1) High recovery rate of microorganism. 2) Shorter turn around time. 3) Easy to communicate between physician and laboratory technician. 4) Effective utilization of blood culture. 5) Getting early information about microorganism. 6) Making antibiogram (microbiological local factor). 7) Getting information for infection control. The disadvantages are operating costs and labor cost. The important point of maximal utilization of onsite microbiology service is close communication between physicians to microbiology laboratory. It will be able to provide prompt and efficient report to physicians through discussion about Gram stain findings, agar plate media findings and epidemiological information. The rapid and accurate identification of pathogen affords directed therapy, thereby decreasing the use of broad-spectrum antibiotics and shortening the length of hospital stay and unnecessary ancillary procedures. When the physician use outsourcing microbiology services, should discuss with offsite laboratories about provided services. Infection control person has to arrange data of susceptibility about every isolate and monitoring multi-drug resistant organism. Not only onsite microbiology services but also outsourcing microbiology services, to communicate bedside and laboratory is most important point of effective utilization.

Identification by PCR and evaluation of probiotic potential in yeast strains found in kefir samples in the city of Santa Maria, RS, Brazil

Directory of Open Access Journals (Sweden)

Daniela CASSANEGO

2017-10-01

Full Text Available Abstract Kefir is a product elaborated from the symbiotic fermentation of different microorganisms. The Kluyveromyces and Saccharomyces genera are the major representatives of the yeasts found in kefir microbiota. The only pobiotic yeast commercialized as an oral medication, is the Saccharomyces boulardii. The present work involved the microbiological quality examination of six kefir samples in the city of Santa Maria/RS, the yeasts isolation present in the samples and the identification of them by PCR (Polymerase chain reaction. Then, their probiotic potential was evaluated by in vitro technique. After that, microbiological analysis confirmed that kefir samples were suitable for consumption once the microbiological quality was established. Nineteen yeast strains were isolated from six different kefir samples; it was identified, by PCR analysis, but only three species were identified from these microorganisms in the present article: Saccharomyces cerevisiae, Hanseniospora uvarum and Kazachstania unispora. Nevertheless, by simulating the passage of isolated strains through the gastrointestinal environment, it was observed that they could not be considered probiotics. The results indicate that, in an isolated way, the yeast presents in kefir samples, in the city of Santa Maria, RS, can´t be considered probiotics according to the tests performed.

Microbiological Quality of Fresh Nopal Juice.

Science.gov (United States)

Hernández-Anguiano, Ana María; Landa-Salgado, Patricia; Eslava-Campos, Carlos Alberto; Vargas-Hernández, Mateo; Patel, Jitendra

2016-12-10

The consumption of fresh nopal cactus juice is widely popular among health-conscious consumers in Mexico. The juice is prepared from fresh cladodes that have only been rinsed with tap water and are not subjected to a pasteurization or terminal bacterial reduction process. The aim of this study was to evaluate the microbial quality of commercially available fresh juices ( n = 162) made with nopal in Texcoco, State of Mexico, during the summer and spring season. Standard microbiological methods, the PCR technique and the serological method were used for isolation and identification of bacteria. All samples contained total coliforms and 91% were positive for Escherichia coli . Although total coliforms and E. coli were detected throughout the study, their populations were significantly lower ( p nopal juices is unacceptable due to its health significance. The information generated in this study is relevant for human health risk assessment associated with the consumption of unpasteurized nopal juices and potential interventions to minimize pathogen contamination.

Microbiological parameters of aggregates in typical chernozems of long-term field experiments

Science.gov (United States)

Zhelezova, A. D.; Tkhakakhova, A. K.; Yaroslavtseva, N. V.; Garbuz, S. A.; Lazarev, V. I.; Kogut, B. M.; Kutovaya, O. V.; Kholodov, V. A.

2017-06-01

The changes in microbiological parameters of aggregates (1-2 mm) in typical chernozems under different land uses as dependent on the intensity and character of anthropogenic loads were studied with the help of the real-time polymerase chain reaction (PCR). The samples from the following long-term field experiments were examined: permanent black fallow, continuous cultivation of potato, 17-year-old unmanaged fallow after permanent black fallow, and annually mown reserved steppe. The soil samples were treated in two ways. In the first case, the samples were air-dried, sieved through the screens to separate aggregate fraction of 1-2 mm, and microbiological parameters were determined in this fraction. In the second case, the samples were frozen immediately after the sampling, and the aggregates of 1-2 mm were manually separated from the samples before the PCR analysis. It was shown that air-dry aggregates of chernozems could be used for the quantitative analysis of DNA of microbial community in comparative studies. According to the quantitative estimate of the content of DNA fragments from different phylogenetic groups, the bacterial community was most sensitive to the type of the soil use, and its restoration after the removal of extreme anthropogenic loads proceeded faster than that of other microorganisms. The content of archaeal DNA in the chernozem under the 17-year-old unmanaged fallow did not differ significantly from its content in the annually plowed chernozems. The changes in the content of micromycetal DNA related to anthropogenic load decrease were intermediate between changes in the contents of archaeal and bacterial DNA.

Microbiological decontamination of natural honey by irradiation

Science.gov (United States)

Migdał, W.; Owczarczyk, H. B.; K ȩdzia, B.; Hołderna-K ȩdzia, E.; Madajczyk, D.

2000-03-01

Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator "Elektronika 10-10" at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency.

Microbiological decontamination of natural honey by irradiation

International Nuclear Information System (INIS)

Migdal, W.; Owczarczyk, H.B.; Kedzia, B.; Holderna-Kedzia, E.; Madajczyk, D.

2000-01-01

Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator ''Elektronika 10-10'' at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency

The effect of addition of selected vegetables on the microbiological, textural and flavour profile properties of yoghurts.

Science.gov (United States)

Najgebauer-Lejko, Dorota; Tabaszewska, Małgorzata; Grega, Tadeusz

2015-01-01

Vegetables, apart from having high nutritional value, also contain considerable amounts of dietary fibre and other components, which may affect physico-chemical properties of fermented milks, e.g. viscosity, texture, susceptibility to syneresis, flavour profile etc. The present work was established to study the effect of selected vegetables addition on the rheological, textural, microbiological and flavour profile parameters of yoghurts. The vegetable preparations (carrot, pumpkin, broccoli and red sweet pepper) were added (10% w/w) to the processed cow's milk fermented with DVS yoghurt culture. Texture profile analysis, determination of viscosity, susceptibility to syneresis and descriptive flavour evaluation were conducted at the 1st, 7th and 14th day after production. Additionally, microbiological studies were performed for 28 days, at 7-day intervals. The highest apparent viscosity and adhesiveness were obtained for the carrot yoghurt, whereas yoghurt with pumpkin was the least susceptible to syneresis. The other texture parameters were not affected by the addition of vegetables. Broccoli and red sweet pepper flavours were dominating in the fermented milks fortified with these vegetables, whereas carrot and pumpkin flavours were less distinctive. Yoghurt supplemented with red sweet pepper got the highest sensoric acceptability. The number of starter bacteria was not influenced by the vegetable additives, except for pumpkin yoghurt, which contained lower population of lactobacilli. Among all tested vegetables, carrot additive had the greatest potential to improve yoghurt structure, whereas red sweet pepper imparted the most acceptable flavour.

42 CFR 493.909 - Microbiology.

Science.gov (United States)

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Microbiology. 493.909 Section 493.909 Public Health... Proficiency Testing Programs by Specialty and Subspecialty § 493.909 Microbiology. The subspecialties under the specialty of microbiology for which a program may offer proficiency testing are bacteriology...

Food microbiology

National Research Council Canada - National Science Library

Royal Society of Chemistry (Great Britain); Moss, M. O; Adams, M. R

2008-01-01

... is directed primarily at students of Microbiology, Food Science and related subjects up to Master's level and assumes some knowledge of basic microbiology. We have chosen not to burden the text with references to the primary literature in order to preserve what we hope is a reasonable narrative flow. Some suggestions for further reading for each chapter are included in Chapter 12. These are largely review articles and monographs which develop the overview provided and can also give access to...

Assessment of chemical composition and microbiological properties of titanium nickelide supernatant

Directory of Open Access Journals (Sweden)

Uruzbaev R.M.

2018-03-01

Full Text Available According to the World Health Organization, in the structure of internal injuries, burns occur in 2.1 per 1000 adults. In practice, all victims after stabilization of the condition are treated surgically with the autodermoplasty, which in the late period is accompanied by a rough scarring, sometimes with the deformation of the damaged area. In addition, infectious complications worsen and aggravate the wound healing process, and also significantly prolong the epithelialization time. A wound is usually infected by opportunistic pathogenic microflora resistant to various groups of antibiotics and antiseptics, by which the affected areas are treated. Modern researches are aimed at finding ways to accelerate regenerative processes of the affected area, to avoid surgical treatment and prevent infection contamination. The object of this study was titanium nickelide supernatant. Currently, there are no published data on the chemical composition of the supernatant, as well as its microbiological safety. This alloy is actively and successfully used in traumatology, dentistry and other fields of medicine. The supernatant was prepared under sterile conditions at a rate of 10 g of titanium nickelide powder per 1 liter of distilled water. In the course of the studies it was proved that nickel and titanium ions are present in the solution, in addition, its bactericidal and bacteriostatic properties are reflected. Thus, the supernatant of nitinol can be used in biological environment and is safe for them.

Environmental microbiology

Science.gov (United States)

Briški, Felicita; Vuković Domanovac, Marija

2017-10-01

For most people, microorganisms are out of sight and therefore out of mind but they are large, extremely diverse group of organisms, they are everywhere and are the dominant form of life on planet Earth. Almost every surface is colonized by microorganisms, including our skin; however most of them are harmless to humans. Some microorganisms can live in boiling hot springs, whereas others form microbial communities in frozen sea ice. Among their many roles, microorganisms are necessary for biogeochemical cycling, soil fertility, decomposition of dead plants and animals and biodegradation of many complex organic compounds present in the environment. Environmental microbiology is concerned with the study of microorganisms in the soil, water and air and their application in bioremediation to reduce environmental pollution through the biological degradation of pollutants into non-toxic or less toxic substances. Field of environmental microbiology also covers the topics such as microbially induced biocorrosion, biodeterioration of constructing materials and microbiological quality of outdoor and indoor air.

Consolidated clinical microbiology laboratories.

Science.gov (United States)

Sautter, Robert L; Thomson, Richard B

2015-05-01

The manner in which medical care is reimbursed in the United States has resulted in significant consolidation in the U.S. health care system. One of the consequences of this has been the development of centralized clinical microbiology laboratories that provide services to patients receiving care in multiple off-site, often remote, locations. Microbiology specimens are unique among clinical specimens in that optimal analysis may require the maintenance of viable organisms. Centralized laboratories may be located hours from patient care settings, and transport conditions need to be such that organism viability can be maintained under a variety of transport conditions. Further, since the provision of rapid results has been shown to enhance patient care, effective and timely means for generating and then reporting the results of clinical microbiology analyses must be in place. In addition, today, increasing numbers of patients are found to have infection caused by pathogens that were either very uncommon in the past or even completely unrecognized. As a result, infectious disease specialists, in particular, are more dependent than ever on access to high-quality diagnostic information from clinical microbiology laboratories. In this point-counterpoint discussion, Robert Sautter, who directs a Charlotte, NC, clinical microbiology laboratory that provides services for a 40-hospital system spread over 3 states in the southeastern United States explains how an integrated clinical microbiology laboratory service has been established in a multihospital system. Richard (Tom) Thomson of the NorthShore University HealthSystem in Evanston, IL, discusses some of the problems and pitfalls associated with large-scale laboratory consolidation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Effectiveness of partially soluble photosensitizer in photodynamic microbiological inactivation: a curcumin example

Science.gov (United States)

Pratavieira, Sebastião.; Matroodi, Fatima; Pinto-Júnior, Fabio Francisco; Rastelli, Alessandra Nara Souza; Bagnato, Vanderlei S.; Guimarães, Francisco E. G.

2017-07-01

We show that partial solubility of a photosensitizer is not necessarily a bad property when dealing with microbiological control. The presence of curcumin aggregates in solution may present advantages with respect the photoand chemical stability.

MICROBIOLOGICAL MONITORING OF YERSINIA AS THE BASIS OF SANITARY AND EPIDEMIOLOGICAL SURVELLANCE OF YERSINIOSIS IN ORGANIZED GROUРS

Directory of Open Access Journals (Sweden)

A. L. Panin

2013-01-01

Full Text Available Abstract. Practical decision of infectology problem depends on the correct assessment of the main concepts of epidemiology and microbiology. The feasibility of attracting the attention of specialists in related disciplines to the problem of microbiological monitoring is discussed. In connection with the capabilities of highly sensitive molecular methods and mathematical modeling on the example of microbiological monitoring of Yersinia was made attempt to analyse mod- ern opportunities of bacteriology and to enter a predictive component as an important element of purposeful activity into monitoring definition. Yersiniosis are one of the most urgent infectious diseases. A variety of biological properties of Yersinia, their various epidemiological importance (Yersinia spp. enter into I, III and the IV groups of virulence, group incidence of Yersiniosis in the organized groups, mobility of genes of a virulence and change of pathogenic properties of Yersinia from strain to strain cause need of carrying out microbiological monitoring with a predictive component in new social and biological conditions. 

21 CFR 866.2540 - Microbiological incubator.

Science.gov (United States)

2010-04-01

...) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2540 Microbiological... intended for medical purposes to cultivate microorganisms and aid in the diagnosis of disease. (b...

Rapid detection of Listeria monocytogenes in foods, by a combination of PCR and DNA probe.

Science.gov (United States)

Ingianni, A; Floris, M; Palomba, P; Madeddu, M A; Quartuccio, M; Pompei, R

2001-10-01

Listeria monocytogenes is a frequent contaminant of water and foods. Its rapid detection is needed before some foods can be prepared for marketing. In this work L. monocytogenes has been searched for in foods, by a combination of polymerase chain reaction (PCR) and a DNA probe. Both PCR and the probe were prepared for recognizing a specific region of the internalin gene, which is responsible for the production of one of the most important pathogenic factors of Listeria. The combined use of PCR and the DNA probe was used for the detection of L. monocytogenes in over 180 environmental and food samples. Several detection methods were compared in this study, namely conventional culture methods; direct PCR; PCR after an enrichment step; a DNA probe alone; a DNA probe after enrichment and another commercially available gene-probe. Finally PCR and the DNA probe were used in series on all the samples collected. When the DNA probe was associated with the PCR, specific and accurate detection of listeria in the samples could be obtained in about a working-day. The present molecular method showed some advantages in terms of rapidity and specificity in comparison to the other aforementioned tests. In addition, it resulted as being easy to handle, even for non-specialized personnel in small diagnostic microbiology laboratories. Copyright 2001 Academic Press.

Identification of Streptococcus pneumoniae lytA, plyA and psaA genes in pleural fluid by multiplex real-time PCR.

Science.gov (United States)

Sanz, Juan Carlos; Ríos, Esther; Rodríguez-Avial, Iciar; Ramos, Belén; Marín, Mercedes; Cercenado, Emilia

2017-08-14

The aim was to evaluate the utility of a multiplex real-time PCR to detect Streptococcus pneumoniae lytA, plyA and psaA genes in pleural fluid (PF). A collection of 81 PF samples was used. Sixty were considered positive for S. pneumoniae according to previous results (54 by an in-house lytA gene PCR and eight by universal rRNA PCR). The sensitivity for detection of the lytA, plyA and psaA genes by multiplex PCR was 100% (60/60), 98.3% (59/60) and 91.7% (55/60), respectively. The detection of all three genes was negative in 21 samples formerly confirmed as negative for S. pneumoniae (100% specificity) by the other procedures (9 by in-house lytA PCR and 12 by rRNA PCR). The use of this multiplex PCR may be a useful option to identify S. pneumoniae directly in PF samples. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Application of PCR-Based Tools to Explore Strongyloides Infection in People in Parts of Northern Australia

Directory of Open Access Journals (Sweden)

Gemma J. Robertson

2017-12-01

Full Text Available Strongyloidiasis, which is caused by infection with the nematode Strongyloides stercoralis, is endemic to areas of northern Australia. Diagnosis in this region remains difficult due to the distances between endemic communities and diagnostic laboratories, leading to lengthy delays in stool processing for microscopy and culture. PCR represents a viable solution to this difficulty, having potential for high sensitivity detection of S. stercoralis, even in older, unpreserved faecal samples. We prospectively collected 695 faecal specimens that were submitted to The Townsville Hospital Microbiology Laboratory from the North Queensland region for routine parasitological examination, and subjected them to a Strongyloides sp. real-time (qPCR. Results were confirmed with a novel nested conventional PCR assay targeting the 18S rRNA gene, followed by single-strand conformation polymorphism analysis (SSCP. Of the 695 specimens tested, S. stercoralis was detected in three specimens (0.4% by classical parasitological methods (direct microscopy and formyl-ether acetate concentration, whereas 42 positives were detected by qPCR (6.0%. Conventional PCR confirmed the real-time PCR results in 24 of the samples (3.5%. Several apparent false-positive results occurred at higher cycle times (Ct in the qPCR. Use of real-time PCR in these populations is promising for the enhanced detection of disease and to support eradication efforts.

MICROBIOLOGICAL QUALITY OF FOOD SUPPLEMENTS.

Science.gov (United States)

Ratajczak, Magdalena; Kubicka, Marcelina M; Kamińska, Dorota; Długaszewska, Jolanta

2015-01-01

Many specialists note that the food offered today - as a result of very complex technological processing - is devoid of many components that are important for the organism and the shortages have to be supplemented. The simplest for it is to consume diet supplements that provide the missing element in a concentrated form. In accordance with the applicable law, medicinal products include all substances or mixtures of substances that are attributed with properties of preventing or treating diseases with humans or animals. Permits to admit supplements to the market are issued by the Chief Sanitary Inspector and the related authorities; permits for medicines are issued by the Chief Pharmaceutical Inspector and the Office for Registration of Medicinal Products, Medical Devices and Biocidal Products. Therefore, admittance of a supplement to the market is less costly and time consuming_than admittance of a medicine. Supplements and medicines may contain the same component but medicines will have a larger concentration than supplements. Sale of supplements at drug stores and in the form of tablets, capsules, liquids or powders makes consumer often confusing supplements with medicines. Now there are no normative documents specifying limits of microbiological impurities in diet supplements. In Polish legislation, diet supplements are subject to legal acts concerning food. Medicines have to comply with microbiological purity requirements specified in the Polish Pharmacopeia. As evidenced with the completed tests, the proportion of diet supplement samples with microbiological impurities is 6.5%. Sales of diet supplements have been growing each year, they are consumed by healthy people but also people with immunology deficiencies and by children and therefore consumers must be certain that they buy safe products.

Establishing molecular microbiology facilities in developing countries

Directory of Open Access Journals (Sweden)

Salman S. Ahmed

2015-11-01

Full Text Available Summary: Microbiology laboratories play an important role in epidemiology and infection control programs. Within microbiology laboratories, molecular microbiology techniques have revolutionized the identification and surveillance of infectious diseases. The combination of excellent sensitivity, specificity, low contamination levels and speed has made molecular techniques appealing methods for the diagnosis of many infectious diseases. In a well-equipped microbiology laboratory, the facility designated for molecular techniques remains indiscrete. However, in most developing countries, poor infrastructure and laboratory mismanagement have precipitated hazardous consequences. The establishment of a molecular microbiology facility within a microbiology laboratory remains fragmented. A high-quality laboratory should include both conventional microbiology methods and molecular microbiology techniques for exceptional performance. Furthermore, it should include appropriate laboratory administration, a well-designed facility, laboratory procedure standardization, a waste management system, a code of practice, equipment installation and laboratory personnel training. This manuscript lays out fundamental issues that need to be addressed when establishing a molecular microbiology facility in developing countries. Keywords: Developing country, Molecular technique, Molecular microbiology laboratory

Microbiological decontamination of natural honey by irradiation

Energy Technology Data Exchange (ETDEWEB)

Migdal, W.; Owczarczyk, H.B.; Kedzia, B.; Holderna-Kedzia, E.; Madajczyk, D

2000-03-01

Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator ''Elektronika 10-10'' at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency.

Detection of Human Bocavirus DNA by Multiplex PCR Analysis: Postmortem Case Report

Directory of Open Access Journals (Sweden)

Nihan Ziyade

2015-06-01

Full Text Available Background: Human bocavirus (HBoV is a virus belonging to the Parvoviridae family, which has been newly discovered to be associated with respiratory tract infections in children. There are many reports worldwide on the endemicity of this virus. Since it is relatively new, it is not routinely detected in clinical laboratory investigations. Case Report: We demonstrated that HBoV infection caused the death of a 5-month-old girl with a history of high fever and wheezing. Human bocavirus (HBoV 1/2/3/4 was found in a nasopharyngeal swab, paraffin-embedded lung tissue and stool samples by multiplex PCR methods using postmortem microbiological analysis. Conclusion: This case suggests that lower respiratory tract infections due to HBoV may cause severe and life-threatening diseases. Postmortem microbiology is useful in both clinical and forensic autopsies, and allows a suspected infection to be confirmed. To our knowledge, this report is the first document of a HBoV postmortem case in Turkey.

Evolution across the Curriculum: Microbiology

Science.gov (United States)

Burmeister, Alita R.; Smith, James J.

2016-01-01

An integrated understanding of microbiology and evolutionary biology is essential for students pursuing careers in microbiology and healthcare fields. In this Perspective, we discuss the usefulness of evolutionary concepts and an overall evolutionary framework for students enrolled in microbiology courses. Further, we propose a set of learning goals for students studying microbial evolution concepts. We then describe some barriers to microbial evolution teaching and learning and encourage the continued incorporation of evidence-based teaching practices into microbiology courses at all levels. Next, we review the current status of microbial evolution assessment tools and describe some education resources available for teaching microbial evolution. Successful microbial evolution education will require that evolution be taught across the undergraduate biology curriculum, with a continued focus on applications and applied careers, while aligning with national biology education reform initiatives. Journal of Microbiology & Biology Education PMID:27158306

Performance of Aspergillus PCR in cerebrospinal fluid for the diagnosis of cerebral aspergillosis.

Science.gov (United States)

Imbert, S; Brossas, J-Y; Palous, M; Joly, I; Meyer, I; Fekkar, A

2017-11-01

Cerebral aspergillosis is a rare but often fatal form of invasive aspergillosis that remains difficult to diagnose. The literature has shown the value of Aspergillus PCR in blood-derived samples for the diagnosis of invasive aspergillosis but provides far less information for cerebrospinal fluid (CSF) in cerebral aspergillosis. Here, we evaluated the usefulness of an Aspergillus PCR assay performed on CSF for the diagnosis of cerebral aspergillosis. This retrospective study involved 72 patients with suspected cerebral aspergillosis for a total of 88 CSF samples in whom CSF Aspergillus PCR was performed. Seventeen patients had proven/probable invasive aspergillosis according to the European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria, including 12 cases of proven/probable cerebral aspergillosis. Aspergillus PCR in CSF was positive in nine of the twelve patients with cerebral aspergillosis, i.e. 75% sensitivity. In contrast, CSF culture was positive for Aspergillus in only two patients. In the non-cerebral aspergillosis group (60 patients), PCR was positive in one patient, i.e. 98.3% specificity. In this particular population of high-risk patients with suspicion of cerebral aspergillosis, the disease incidence was 16.7%. Therefore, the positive and negative predictive values of PCR were 90% and 95.2%, respectively. The results of this study indicate that Aspergillus PCR in CSF is an interesting tool that may eliminate the need for cerebral biopsy in patients with suspected cerebral aspergillosis. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Meta-analysis in microbiology

Directory of Open Access Journals (Sweden)

N Pabalan

2014-01-01

Full Text Available The use of meta-analysis in microbiology may facilitate decision-making that impacts public health policy. Directed at clinicians and researchers in microbiology, this review outlines the steps in performing this statistical technique, addresses its biases and describes its value in this discipline. The survey to estimate extent of the use of meta-analyses in microbiology shows the remarkable growth in the use of this research methodology, from a minimal Asian output to a level comparable with those of Europe and North America in the last 7 years.

Evaluation of the performance of quantitative detection of the Listeria monocytogenes prfA locus with droplet digital PCR.

Science.gov (United States)

Witte, Anna Kristina; Fister, Susanne; Mester, Patrick; Schoder, Dagmar; Rossmanith, Peter

2016-11-01

Fast and reliable pathogen detection is an important issue for human health. Since conventional microbiological methods are rather slow, there is growing interest in detection and quantification using molecular methods. The droplet digital polymerase chain reaction (ddPCR) is a relatively new PCR method for absolute and accurate quantification without external standards. Using the Listeria monocytogenes specific prfA assay, we focused on the questions of whether the assay was directly transferable to ddPCR and whether ddPCR was suitable for samples derived from heterogeneous matrices, such as foodstuffs that often included inhibitors and a non-target bacterial background flora. Although the prfA assay showed suboptimal cluster formation, use of ddPCR for quantification of L. monocytogenes from pure bacterial cultures, artificially contaminated cheese, and naturally contaminated foodstuff was satisfactory over a relatively broad dynamic range. Moreover, results demonstrated the outstanding detection limit of one copy. However, while poorer DNA quality, such as resulting from longer storage, can impair ddPCR, internal amplification control (IAC) of prfA by ddPCR, that is integrated in the genome of L. monocytogenes ΔprfA, showed even slightly better quantification over a broader dynamic range. Graphical Abstract Evaluating the absolute quantification potential of ddPCR targeting Listeria monocytogenes prfA.

Reduction in Acidity by Chemical and Microbiological Methods and Their Effect on Moslavac Wine Quality

OpenAIRE

Herjavec, Stanka; Majdak, Ana; Tupajić, Pavica; Redžepović, Sulejman; Orlić, Sandi

2003-01-01

Changes in chemical composition and sensory properties caused by chemical and microbiological methods of deacidification in Moslavac (syn. Furmint) wines were investigated. Alcoholic fermentation of Moslavac musts was carried out with two different strains of the yeasts Saccharomyces paradoxus. There were no marked differences in chemical composition among the wines. Compared to the control microbiological deacidification of wines by Oenococcus oeni resulted in a complete decomposition of mal...

Effect of gamma irradiation on microbiological, chemical, and sensory properties of fresh ashitaba and kale juices

Science.gov (United States)

Jo, Cheorun; Ahn, Dong Uk; Lee, Kyung Haeng

2012-08-01

Due to the popularity of health effects upon intake of fresh fruits and vegetables, the demand for fresh vegetables and fruit juices has rapidly increased. However, currently, washing is the only procedure for reducing contaminated microorganisms, which obviously limits the shelf-life of fresh vegetable juice (less than 3 days). In this study, we examined the effects of irradiation on the microbiological, chemical and sensory properties of ashitaba and kale juices for industrial application and possible shelf-life extension. Freshly made ashitaba and kale juices already had 2.3×105 and 9.5×104 CFU/mL, respectively. Irradiation of 5 kGy induced higher than 2 decimal reductions in the microbial level, which was consistently maintained during storage for 7 days under refrigerated conditions. Total content of ascorbic acid in vegetable juice decreased upon irradiation in a dose-dependent manner. However, the content of flavonoids did not change, whereas that of polyphenols increased upon irradiation. In sensory evaluation, the ashitaba and kale juices without irradiation (control) scored lower than the irradiated samples after 1 and 3 days, respectively. This study confirms that irradiation is an effective method for sterilizing fresh vegetable juice without compromising sensory property, which cannot be subjected to heat pasteurization due to changes in the bioactivities of the products.

Introduction on Using the FastPCR Software and the Related Java Web Tools for PCR and Oligonucleotide Assembly and Analysis.

Science.gov (United States)

Kalendar, Ruslan; Tselykh, Timofey V; Khassenov, Bekbolat; Ramanculov, Erlan M

2017-01-01

This chapter introduces the FastPCR software as an integrated tool environment for PCR primer and probe design, which predicts properties of oligonucleotides based on experimental studies of the PCR efficiency. The software provides comprehensive facilities for designing primers for most PCR applications and their combinations. These include the standard PCR as well as the multiplex, long-distance, inverse, real-time, group-specific, unique, overlap extension PCR for multi-fragments assembling cloning and loop-mediated isothermal amplification (LAMP). It also contains a built-in program to design oligonucleotide sets both for long sequence assembly by ligase chain reaction and for design of amplicons that tile across a region(s) of interest. The software calculates the melting temperature for the standard and degenerate oligonucleotides including locked nucleic acid (LNA) and other modifications. It also provides analyses for a set of primers with the prediction of oligonucleotide properties, dimer and G/C-quadruplex detection, linguistic complexity as well as a primer dilution and resuspension calculator. The program consists of various bioinformatical tools for analysis of sequences with the GC or AT skew, CG% and GA% content, and the purine-pyrimidine skew. It also analyzes the linguistic sequence complexity and performs generation of random DNA sequence as well as restriction endonucleases analysis. The program allows to find or create restriction enzyme recognition sites for coding sequences and supports the clustering of sequences. It performs efficient and complete detection of various repeat types with visual display. The FastPCR software allows the sequence file batch processing that is essential for automation. The program is available for download at http://primerdigital.com/fastpcr.html , and its online version is located at http://primerdigital.com/tools/pcr.html .

Microbiology Education in Nursing Practice?

OpenAIRE

Durrant, Robert J.; Doig, Alexa K.; Buxton, Rebecca L.; Fenn, JoAnn P.

2017-01-01

Nurses must have sufficient education and training in microbiology to perform many roles within clinical nursing practice (e.g., administering antibiotics, collecting specimens, preparing specimens for transport and delivery, educating patients and families, communicating results to the healthcare team, and developing care plans based on results of microbiology studies and patient immunological status). It is unclear whether the current microbiology courses required of nursing students in the...

Detection of adenoviruses in shellfish by means of conventional-PCR, nested-PCR, and integrated cell culture PCR (ICC/PCR).

Science.gov (United States)

Rigotto, C; Sincero, T C M; Simões, C M O; Barardi, C R M

2005-01-01

We tested three PCR based methodologies to detect adenoviruses associated with cultivated oysters. Conventional-PCR, nested-PCR, and integrated cell culture-PCR (ICC/PCR) were first optimized using oysters seeded with know amounts of Adenovirus serotype 5 (Ad5). The maximum sensitivity for Ad5 detection was determined for each method, and then used to detect natural adenovirus contamination in oysters from three aquiculture farms in Florianopolis, Santa Catarina State, Brazil, over a period of 6 months. The results showed that the nested-PCR was more sensitive (limit of detection: 1.2 PFU/g of tissue) than conventional-PCR and ICC-PCR (limit of detection for both: 1.2 x 10(2)PFU/g of tissue) for detection of Ad5 in oyster extracts. Nested-PCR was able to detect 90% of Ad5 contamination in harvested oyster samples, while conventional-PCR was unable to detect Ad5 in any of the samples. The present work suggests that detection of human adenoviruses can be used as a tool to monitor the presence of human viruses in marine environments where shellfish grow, and that nested-PCR is the method of choice.

Oral Microbiology and Immunology

DEFF Research Database (Denmark)

Dahlén, Gunnar; Fiehn, Nils-Erik; Olsen, Ingar

, dental assistants and trainees may find it a useful source of reference. The contents are based on general microbiology and immunology. Oral microbiology is given particular attention, with examples relevant to oral infectious diseases. Each chapter opens with a relatively short pre-reading section...

ViDiT-CACTUS: an inexpensive and versatile library preparation and sequence analysis method for virus discovery and other microbiology applications.

Science.gov (United States)

Verhoeven, Joost Theo Petra; Canuti, Marta; Munro, Hannah J; Dufour, Suzanne C; Lang, Andrew S

2018-04-19

High-throughput sequencing (HTS) technologies are becoming increasingly important within microbiology research, but aspects of library preparation, such as high cost per sample or strict input requirements, make HTS difficult to implement in some niche applications and for research groups on a budget. To answer these necessities, we developed ViDiT, a customizable, PCR-based, extremely low-cost (90% coverage), and the characterization and functional profiling of the complete microbial diversity (bacteria, archaea, viruses) within a deep-sea carnivorous sponge. ViDiT-CACTUS demonstrated its validity in a wide range of microbiology applications and its simplicity and modularity make it easily implementable in any molecular biology laboratory, towards various research goals.

[The modern microbiology in the clinical managing].

Science.gov (United States)

Casal Román, Manuel

2012-01-01

The tuberculosis is one of the most important and mortal diseases of the world. The microbiological confirmatory diagnosis and the microbiological therapeutic orientation are fundamental nowadays in the tuberculosis in AIDS and in the Resistant tuberculosis. They are described throughout the time by the classic Microbiology: From 1882 to final 20th century (130 years). With the modern current Microbiology: In the beginning of the 21st century (20-30 years). And as will be done with the future Microbiology: From the years 2020-30. The important advances are outlined in the modern and future clinical microbiology, for the control of the Tuberculosis.

Microbiology and atmospheric processes: chemical interactions of primary biological aerosols

Directory of Open Access Journals (Sweden)

L. Deguillaume

2008-07-01

Full Text Available This paper discusses the influence of primary biological aerosols (PBA on atmospheric chemistry and vice versa through microbiological and chemical properties and processes. Several studies have shown that PBA represent a significant fraction of air particulate matter and hence affect the microstructure and water uptake of aerosol particles. Moreover, airborne micro-organisms, namely fungal spores and bacteria, can transform chemical constituents of the atmosphere by metabolic activity. Recent studies have emphasized the viability of bacteria and metabolic degradation of organic substances in cloud water. On the other hand, the viability and metabolic activity of airborne micro-organisms depend strongly on physical and chemical atmospheric parameters such as temperature, pressure, radiation, pH value and nutrient concentrations. In spite of recent advances, however, our knowledge of the microbiological and chemical interactions of PBA in the atmosphere is rather limited. Further targeted investigations combining laboratory experiments, field measurements, and modelling studies will be required to characterize the chemical feedbacks, microbiological activities at the air/snow/water interface supplied to the atmosphere.

Comparative study of microbiological, chemical and sensory properties of kefirs produced in Estonia, Latvia and Lithuania.

Science.gov (United States)

Anton, Dea; Raudsepp, Piret; Roasto, Mati; Meremäe, Kadrin; Kuusik, Sirje; Toomik, Peeter; Elias, Priit; Laikoja, Katrin; Kaart, Tanel; Lepiku, Martin; Püssa, Tõnu

2016-02-01

In the current study the microbiological, sensory and chemical properties of 24 kefirs (12 producers) from Estonian, Latvian and Lithuanian retail market were determined using gas chromatography (GC), high performance liquid chromatography (HPLC-MS/MS-Q-TOF and LC-ion trap MS/MS), spectrophotometry and other methods. Antihypertensive, angiotensin-converting enzyme (ACE) inhibiting, antioxidant and antibacterial peptides were found in the kefir samples. According to the results of principal component analysis of 200 most abundant compounds obtained with HPLC-MS/MS-Q-TOF analysis, Estonian kefirs differed from the rest. Kefirs of Latvian and Lithuanian origin showed similarities in several characteristics, probably related to the starter cultures and technological processes. The fatty acids composition of all Baltic kefirs was uniform. The antioxidant capacity of the kefirs varied slightly, whereas intermediate positive correlation (r = 0.32, P kefirs. Only one third of analysed kefirs met the requirements of the minimum sum of viable microorganisms, indicated in the Codex Standard for Fermented Milks.

Microbiological Food Safety Surveillance in China

Directory of Open Access Journals (Sweden)

Xiaoyan Pei

2015-08-01

Full Text Available Microbiological food safety surveillance is a system that collects data regarding food contamination by foodborne pathogens, parasites, viruses, and other harmful microbiological factors. It helps to understand the spectrum of food safety, timely detect food safety hazards, and provide relevant data for food safety supervision, risk assessment, and standards-setting. The study discusses the microbiological surveillance of food safety in China, and introduces the policies and history of the national microbiological surveillance system. In addition, the function and duties of different organizations and institutions are provided in this work, as well as the generation and content of the surveillance plan, quality control, database, and achievement of the microbiological surveillance of food safety in China.

A one-step multiplex RT-PCR assay for simultaneous detection of four viruses that infect peach.

Science.gov (United States)

Yu, Y; Zhao, Z; Jiang, D; Wu, Z; Li, S

2013-10-01

A multiplex reverse transcription polymerase chain reaction (mRT-PCR) assay was developed to enable the simultaneous detection and differentiation of four viruses that infect peach, namely Apple chlorotic leaf spot virus (ACLSV), Cherry green ring mottle virus (CGRMV), Prunus necrotic ringspot virus (PNRSV) and Apricot pseudo-chlorotic leaf spot virus (APCLSV). In this study, four pairs of primers, one specific for each virus, were designed; the corresponding PCR products were 632, 439, 346 and 282 bp in length for ACLSV, CGRMV, PNRSV and APCLSV, respectively, and the fragments could be distinguished clearly by agarose gel electrophoresis. The sensitivity and specificity of the method were tested using individual RT-PCR and enzyme-linked immunosorbent assay (ELISA), and the identity of the RT-PCR amplification products was also confirmed by DNA sequencing. The results of RT-PCR and ELISA, along with batch detection using samples collected from peach orchards, revealed that this rapid and simple technique is an effective way to identify the four viruses simultaneously. The mRT-PCR assay described in this study was developed for the simultaneous detection of four peach viruses from infected peach samples is reliable and sensitive. In contrast to conventional uniplex RT-PCR, mRT-PCR is more efficient, reducing costs, time and handling when testing large numbers of samples. This rapid and simple method is useful for large-scale surveys of viruses that infect peach. © 2013 The Society for Applied Microbiology.

Comparison of the Microbiological Quality and Safety between Conventional and Organic Vegetables Sold in Malaysia

Directory of Open Access Journals (Sweden)

Chee-Hao Kuan

2017-07-01

Full Text Available 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

Comparison of the Microbiological Quality and Safety between Conventional and Organic Vegetables Sold in Malaysia.

Science.gov (United States)

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

Comparison of the Microbiological Quality and Safety between Conventional and Organic Vegetables Sold in Malaysia

Science.gov (United States)

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

42 CFR 493.821 - Condition: Microbiology.

Science.gov (United States)

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Condition: Microbiology. 493.821 Section 493.821 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... These Tests § 493.821 Condition: Microbiology. The specialty of microbiology includes, for purposes of...

"Salvage microbiology": detection of bacteria directly from clinical specimens following initiation of antimicrobial treatment.

Directory of Open Access Journals (Sweden)

John J Farrell

Full Text Available PCR coupled with electrospray ionization mass spectrometry (ESI-MS is a diagnostic approach that has demonstrated the capacity to detect pathogenic organisms from culture negative clinical samples after antibiotic treatment has been initiated. [1] We describe the application of PCR/ESI-MS for detection of bacteria in original patient specimens that were obtained after administration of antibiotic treatment in an open investigation analysis.We prospectively identified cases of suspected bacterial infection in which cultures were not obtained until after the initiation of antimicrobial treatment. PCR/ESI-MS was performed on 76 clinical specimens that were submitted for conventional microbiology testing from 47 patients receiving antimicrobial treatment.In our series, 72% (55/76 of cultures obtained following initiation of antimicrobial treatment were non-diagnostic (45 negative cultures; and 10 respiratory specimens with normal flora (5, yeast (4, or coagulase-negative staphylococcus (1. PCR/ESR-MS detected organisms in 83% (39/47 of cases and 76% (58/76 of the specimens. Bacterial pathogens were detected by PCR/ESI-MS in 60% (27/45 of the specimens in which cultures were negative. Notably, in two cases of relapse of prosthetic knee infections in patients on chronic suppressive antibiotics, the previous organism was not recovered in tissue cultures taken during extraction of the infected knee prostheses, but was detected by PCR/ESI-MS.Molecular methods that rely on nucleic acid amplification may offer a unique advantage in the detection of pathogens collected after initiation of antimicrobial treatment and may provide an opportunity to target antimicrobial therapy and "salvage" both individual treatment regimens as well as, in select cases, institutional antimicrobial stewardship efforts.

Efficacy of Pulsed-Field Gel Electrophoresis and Repetitive Element Sequence-Based PCR in Typing of Salmonella Isolates from Assam, India.

Science.gov (United States)

Gogoi, Purnima; Borah, Probodh; Hussain, Iftikar; Das, Leena; Hazarika, Girin; Tamuly, Shantanu; Barkalita, Luit Moni

2018-05-01

A total of 12 Salmonella isolates belonging to different serovars, viz , Salmonella enterica serovar Enteritidis ( n = 4), Salmonella enterica serovar Weltevreden ( n = 4), Salmonella enterica serovar Newport ( n = 1), Salmonella enterica serovar Litchifield ( n = 1), and untypeable strains ( n = 2) were isolated from 332 diarrheic fecal samples collected from animals, birds, and humans. Of the two molecular typing methods applied, viz , repetitive element sequence-based PCR (REP-PCR) and pulsed-field gel electrophoresis (PFGE), PFGE could clearly differentiate the strains belonging to different serovars as well as differentiate between strains of the same serovar with respect to their source of isolation, whereas REP-PCR could not differentiate between strains of the same serovar. Thus, it can be suggested that PFGE is more useful and appropriate for molecular typing of Salmonella isolates during epidemiological investigations than REP-PCR. Copyright © 2018 American Society for Microbiology.

Usefulness of real-time PCR as a complementary tool to the monitoring of Legionella spp. and Legionella pneumophila by culture in industrial cooling systems.

Science.gov (United States)

Touron-Bodilis, A; Pougnard, C; Frenkiel-Lebossé, H; Hallier-Soulier, S

2011-08-01

This study was designed to evaluate the usefulness of quantification by real-time PCR as a management tool to monitor concentrations of Legionella spp. and Legionella pneumophila in industrial cooling systems and its ability to anticipate culture trends by the French standard method (AFNOR T90-431). Quantifications of Legionella bacteria were achieved by both methods on samples from nine cooling systems with different water qualities. Proportion of positive samples for L. pneumophila quantified by PCR was clearly lower in deionized or river waters submitted to a biocide treatment than in raw river waters, while positive samples for Legionella spp. were quantified for almost all the samples. For some samples containing PCR inhibitors, high quantification limits (up to 4·80 × 10(5) GU l(-1) ) did not allow us to quantify L. pneumophila, when they were quantified by culture. Finally, the monitoring of concentrations of L. pneumophila by both methods showed similar trends for 57-100% of the samples. These results suggest that, if some methodological steps designed to reduce inhibitory problems and thus decrease the quantification limits, could be developed to quantify Legionella in complex waters, the real-time PCR could be a valuable complementary tool to monitor the evolution of L. pneumophila concentrations. This study shows the possibility of using real-time PCR to monitor L. pneumophila proliferations in cooling systems and the importance to adapt nucleic acid extraction and purification protocols to raw waters. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology. No claim to French Government works.

Evaluation of PCR and multiplex PCR in relation to nested PCR for diagnosing Theileria equi

Directory of Open Access Journals (Sweden)

Danielle C. Leal

2011-07-01

Full Text Available Conventional PCR (PCRTeq for diagnosing Theileria equi and multiplex PCR (M/PCRTeq-Bc for diagnosing T. equi and Babesia caballi were comparatively evaluated with nested PCR (N/PCR-Teq for diagnosing equine piroplasmosis. In DNA sensitivity determinations, in multiple dilutions of equine blood that had tested positive for T. equi, PCR-Teq and N/PCR-Teq detected hemoparasite DNA in the larger dilutions (1:128, but did not differ significantly from the M/PCRTeq-Bc (1:64. In analyses on equine serum tested by ELISA, there was high agreement between this serological test and PCR-Teq (k = 0.780 and moderate agreement with N/PCR-Teq (k = 0.562 and M/PCRTeq-Bc (k = 0.488. PCR-Teq found a higher frequency of T. equi both in extensively and intensively reared horses, but this was not significant in relation to N/PCR-Teq (P>0.05, and both PCRs indicated that there was an endemic situation regarding T. equi in the population of horses of this sample. PCR-Teq was only significantly different from M/PCR-Teq-Bc (P<0.05. PCR-Teq presented high sensitivity and specificity, comparable to N/PCR-Teq, but with the advantage of higher speed in obtaining results and lower costs and risks of laboratory contamination. This accredits PCR-Teq for epidemiological studies and for determinations on affected horses.

OpenStax: Microbiology Provides a Cost-Effective and Accessible Resource for Undergraduate Microbiology Students

Directory of Open Access Journals (Sweden)

Amanda Lyn Gunn

2016-05-01

Full Text Available This is a review of Openstax: Microbiology, a textbook that has been put together by a collaborative effort between Openstax College and the American Society for Microbiology.  The text will be offered in a variety of formats including web-based, PDF, and hardcopy, and is set for publication Spring 2016. Review of: OpenStax: Microbiology. Nina Parker, Mark Schneegurt, and Anh-Hue Tu; (2016. OpenStax and ASM. 1100 pages. (Note: At time of journal printing, this book was not yet published. Certain publication details may change slightly.

Veterinary microbiology and microbial disease

National Research Council Canada - National Science Library

Quinn, P. J

2011-01-01

"Veterinary Microbiology is one of the core subjects for veterinary students. Fully revised and expanded, this new edition covers every aspect of veterinary microbiology for students in both paraclinical and clinical years...

Detection of virulence genes in Uropathogenic E. coli (UPEC strains by Multiplex-PCR method

Directory of Open Access Journals (Sweden)

Javad Mohammadi

2017-06-01

Full Text Available Background & Objectives: Urinary tract infection caused by E. coli is one of the most common illnesses in all age groups worldwide. Presence of virulence genes is a key factor in bacterial pathogens in uroepithelial cells. The present study was performed to detect iha, iroN, ompT genes in the Uropathogenic E.coli isolates from clinical samples using multiplex-PCR method in Kerman. Materials & Methods: In this descriptive cross-sectional study, 200 samples of patients with urinary tract infections in Kerman hospitals were collected. After biochemical and microbiological tests, all strains were tested with regard to the presence of iha, iroN, and ompT genes using multiplex-PCR method. Results: The results of Multiplex-PCR showed that all specimens had one, two, or three virulence genes simultaneously. The highest and lowest frequency distribution of genes was related to iha (56.7% and iroN (20% respectively. Conclusion: According to the prevalence of urinary tract infection in the community and distribution of resistance and virulence factors, the fast and accurate detection of the strains and virulence genes is necessary

Physicochemical, microbiological, and colour attributes of horse salami established during the ripening period

Directory of Open Access Journals (Sweden)

D. KOVACEVIC

2016-03-01

Full Text Available Changes in physicochemical, colour, textural, microbiological and sensory attributes occurring during the processing of Horse Salami and established on manufacturing days 0, 7, 14, 21, 28, 42, 60, 90 were studied. Significant changes (P<0.05 in physicochemical parameters attributable to moisture loss, as well as changes in colour and textural properties were observed during the fermentation and ripening stage. Proteolysis and lipolysis, coming as a result of endogenous enzymatic activity and high lactic acid bacteria and staphylococci counts, contributed to specific organoleptic properties of the final product. Sensorial profiling showed a significant (P<0.05 acid taste, lactic acid odour and flavour intensity, and low fat/lean ratio and smokiness and saltiness values. Final Horse Salami products were microbiologically safe, the dominant microbial population thereby being Lactobacillus plantarum, Lactococcus lactis ssp. lactis, Enterococcus faeciumand Staphylococcus xylosus.

Assessment of Clinically Suspected Tubercular Lymphadenopathy by Real-Time PCR Compared to Non-Molecular Methods on Lymph Node Aspirates.

Science.gov (United States)

Gupta, Vivek; Bhake, Arvind

2018-01-01

The diagnosis of tubercular lymphadenitis (TBLN) is challenging. This study assesses the role of diagnostic intervention with real-time PCR in clinically suspected tubercular lymphadenopathy in relation to cytology and microbiological methods. The cross-sectional study involved 214 patients, and PCR, cytology, and Ziehl-Neelsen (ZN) staining was performed on aspirates. The findings were compared with culture on Lowenstein-Jensen medium. The overall concordance of cytology and PCR, both individually and combined, was calculated. χ2 and Phi values were assessed between cytology, PCR, and culture. A cytological diagnosis of tuberculosis (TB), reactive lymphoid hyperplasia, and suppurative lymphadenitis was made in 71, 112, and 6 patients, respectively. PCR and culture were positive in 40% of the cases. Among the TBLN patients, PCR showed higher positivity in necrosis and culture showed higher positivity in necrotizing granuloma. Positive ZN staining was observed in 29.6% of the TBLN cases, with an overall positivity of 11%. PCR could additionally detect 82 cases missed by ZN staining. The overall concordance rate for either diagnostic modality, i.e., PCR or cytology, was highest (75%), and for PCR alone was 74%. Phi values were observed to be 0.47 between PCR and culture. Real-time PCR for Mycobacterium tuberculosis complex on aspirates offers a definitive and comparable diagnosis of TBLN. Including this approach as the primary investigation in the work-up of TBLN could reduce the burden of TB. © 2017 S. Karger AG, Basel.

The effects of superchilled storage at -2 C on the microbiological and organoleptic properties of cold-smoked salmon before retail display

Energy Technology Data Exchange (ETDEWEB)

Beaufort, A. [AFSSA Lerqap, 23 avenue du General de Gaulle, FR-94706 Maisons-Alfort Cedex (France); Cardinal, M. [IFREMER, STAM, rue de l' Ile d' Yeu, FR- 44311 Nantes Cedex 3 (France); Le-Bail, A. [ENITIAA, UMR GEPEA, CNRS 6144, rue de la Geraudiere, BP 82225, FR-44322 Nantes (France); Midelet-Bourdin, G. [AFSSA Lerppe, boulevard du Bassin Napoleon, FR-62200 Boulogne-sur-Mer (France)

2009-11-15

The aim of this study was to investigate the impact of superchilling (-2 C) on the evolution of Listeria monocytogenes and organoleptic characteristics of cold-smoked salmon samples. An Hadamard matrix experimental design was carried out on artificially inoculated samples stored at +4 C for 10 d and at +8 C for 18 d to know the influence of four factors: salt content, strain, cold stiffening and superchilling time, on the level of L.monocytogenes in cold-smoked salmon. The growth of L. monocytogenes in naturally contaminated cold-smoked salmon and the organoleptic properties were investigated under superchilling conditions. Superchilling (-2 C for 28 d) had a limited impact on some of the organoleptic properties but the level of L. monocytogenes at the end of the shelf-life (4 C for 10 d and 8 C for 18 d) could exceed the microbiological criterion set by the European legislation. (author)

Multiplex real-time PCR (TaqMan) assay for the simultaneous detection and discrimination of potato powdery and common scab diseases and pathogens.

Science.gov (United States)

Qu, X S; Wanner, L A; Christ, B J

2011-03-01

To develop a multiplex real-time PCR assay using TaqMan probes for the simultaneous detection and discrimination of potato powdery scab and common scab, two potato tuber diseases with similar symptoms, and the causal pathogens Spongospora subterranea and plant pathogenic Streptomyces spp. Real-time PCR primers and a probe for S. subterranea were designed based on the DNA sequence of the ribosomal RNA ITS2 region. Primers and a probe for pathogenic Streptomyces were designed based on the DNA sequence of the txtAB genes. The two sets of primer pairs and probes were used in a single real-time PCR assay. The multiplex real-time PCR assay was confirmed to be specific for S. subterranea and pathogenic Streptomyces. The assay detected DNA quantities of 100 fg for each of the two pathogens and linear responses and high correlation coefficients between the amount of DNA and C(t) values for each pathogen were achieved. The presence of two sets of primer pairs and probes and of plant extracts did not alter the sensitivity and efficiency of multiplex PCR amplification. Using the PCR assay, we could discriminate between powdery scab and common scab tubers with similar symptoms. Common scab and powdery scab were detected in some tubers with no visible symptoms. Mixed infections of common scab and powdery scab on single tubers were also revealed. This multiplex real-time PCR assay is a rapid, cost efficient, specific and sensitive tool for the simultaneous detection and discrimination of the two pathogens on infected potato tubers when visual symptoms are inconclusive or not present. Accurate and quick identification and discrimination of the cause of scab diseases on potatoes will provide critical information to potato growers and researchers for disease management. This is important because management strategies for common and powdery scab diseases are very different. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Sheep milk yogurt from a short food supply chain: study of the microbiological, chemico-physical and organoleptic parameters in relation to shelf-life

Directory of Open Access Journals (Sweden)

Nicla Marri

2014-08-01

Full Text Available Aim of this work was to analyse some microbiological, chemico-physical and organoleptic parameters of sheep milk yogurt during and after its declared shelf-life. Five samples of a sheep’s milk yogurt of the same lot, collected from a short supply chain ovine dairy farm of the Roman province, were analysed. Declared shelf-life of the product was 30 days. The products were examined at 2, 14, 30, 35 and 40 days from the production date, performing the following microbiological analyses: enumeration of i colony-forming units characteristic of the yogurt, ii Enterobacteriaceae, iii yeasts and/or moulds at 25°C. Microbiological identification was performed by miniature biochemical tests and for the lactic acid bacteria also by PCR. At every test interval, evaluation of organoleptic parameters and pH was also performed. The analysed product maintained an almost constant amount of lactic acid bacteria until the end of the declared shelf-life. Concerning lactic acid bacteria, a 100% concordance of the results observed by using biochemical identification methods and PCR assays was obtained. After 14 days from the production, the presence of yeasts (Candida famata was revealed, while the presence of moulds was detected after 30 days. Ralstonia picketii, an environmental microorganism, was also isolated. The results obtained in this study indicate that yogurt spoilage is mainly due to the growth of specific microorganisms of spoilage, such as yeasts and moulds.

Multiplexed Single Intact Cell Droplet Digital PCR (MuSIC ddPCR) Method for Specific Detection of Enterohemorrhagic E. coli (EHEC) in Food Enrichment Cultures.

Science.gov (United States)

McMahon, Tanis C; Blais, Burton W; Wong, Alex; Carrillo, Catherine D

2017-01-01

Foodborne illness attributed to enterohemorrhagic E. coli (EHEC), a highly pathogenic subset of Shiga toxin-producing E. coli (STEC), is increasingly recognized as a significant public health issue. Current microbiological methods for identification of EHEC in foods often use PCR-based approaches to screen enrichment broth cultures for characteristic gene markers [i.e., Shiga toxin ( stx ) and intimin ( eae )]. However, false positives arise when complex food matrices, such as beef, contain mixtures of eae -negative STEC and eae -positive E. coli , but no EHEC with both markers in a single cell. To reduce false-positive detection of EHEC in food enrichment samples, a Multiplexed, Single Intact Cell droplet digital PCR (MuSIC ddPCR) assay capable of detecting the co-occurrence of the stx and eae genes in a single bacterial cell was developed. This method requires: (1) dispersal of intact bacteria into droplets; (2) release of genomic DNA (gDNA) by heat lysis; and (3) amplification and detection of genetic targets ( stx and eae ) using standard TaqMan chemistries with ddPCR. Performance of the method was tested with panels of EHEC and non-target E. coli . By determining the linkage (i.e., the proportion of droplets in which stx and eae targets were both amplified), samples containing EHEC (typically greater than 20% linkage) could be distinguished from samples containing mixtures of eae -negative STEC and eae -positive E. coli (0-2% linkage). The use of intact cells was necessary as this linkage was not observed with gDNA extracts. EHEC could be accurately identified in enrichment broth cultures containing excess amounts of background E. coli and in enrichment cultures derived from ground beef/pork and leafy-green produce samples. To our knowledge, this is the first report of dual-target detection in single bacterial cells using ddPCR. The application of MuSIC ddPCR to enrichment-culture screening would reduce false-positives, thereby improving the cost, speed, and

[Microbiological diagnosis of HIV infection].

Science.gov (United States)

López-Bernaldo de Quirós, Juan Carlos; Delgado, Rafael; García, Federico; Eiros, José M; Ortiz de Lejarazu, Raúl

2007-12-01

Currently, there are around 150,000 HIV-infected patients in Spain. This number, together with the fact that this disease is now a chronic condition since the introduction of antiretroviral therapy, has generated an increasing demand on the clinical microbiology laboratories in our hospitals. This increase has occurred not only in the diagnosis and treatment of opportunistic diseases, but also in tests related to the diagnosis and therapeutic management of HIV infection. To meet this demand, the Sociedad de Enfermedades Infecciosas y Microbiología Clinica (Spanish Society of Infectious Diseases and Clinical Microbiology) has updated its standard Procedure for the microbiological diagnosis of HIV infection. The main advances related to serological diagnosis, plasma viral load, and detection of resistance to antiretroviral drugs are reviewed in this version of the Procedure.

MICROBIOLOGICAL CHARACTERISTICS OF MILK FROM DONKEYS FARMED IN CAMPANIA REGION: PRELIMINARY RESULTS

Directory of Open Access Journals (Sweden)

E. Sarno

2012-08-01

Full Text Available Interest in donkey’s milk destined to human consumption is increasing owing to its complex composition and unique functional properties. The microbiological profile of donkeys’ raw milk was investigated. Individual donkey milk samples were collected from 8 asses after mechanical milking and filtration in a farm of Campania region. A total of 133 samples were analyzed. Total plate count bacteria and Enterobacteriaceae were enumerated. Other microbiological characteristics were monitored as established by legislation in force on the sale of raw milk. Results showed a low contamination level of the raw milk in accordance with other authors. No correlations were evidenced between milk contamination and lactation stage.

DNA extraction methods for panbacterial and panfungal PCR detection in intraocular fluids.

Science.gov (United States)

Mazoteras, Paloma; Bispo, Paulo José Martins; Höfling-Lima, Ana Luisa; Casaroli-Marano, Ricardo P

2015-07-01

Three different methods of DNA extraction from intraocular fluids were compared with subsequent detection for bacterial and fungal DNA by universal PCR amplification. Three DNA extraction methods, from aqueous and vitreous humors, were evaluated to compare their relative efficiency. Bacterial (Gram positive and negative) and fungal strains were used in this study: Escherichia coli, Staphylococcus epidermidis and Candida albicans. The quality, quantification, and detection limit for DNA extraction and PCR amplification were analyzed. Validation procedures for 13 aqueous humor and 14 vitreous samples, from 20 patients with clinically suspected endophthalmitis were carried out. The column-based extraction method was the most time-effective, achieving DNA detection limits ≥10(2) and 10(3 )CFU/100 µL for bacteria and fungi, respectively. PCR amplification detected 100 fg, 1 pg and 10 pg of genomic DNA of E. coli, S. epidermidis and C. albicans respectively. PCR detected 90.0% of the causative agents from 27 intraocular samples collected from 20 patients with clinically suspected endophthalmitis, while standard microbiological techniques could detect only 60.0%. The most frequently found organisms were Streptococcus spp. in 38.9% (n = 7) of patients and Staphylococcus spp. found in 22.2% (n = 4). The column-based extraction method for very small inocula in small volume samples (50-100 µL) of aqueous and/or vitreous humors allowed PCR amplification in all samples with sufficient quality for subsequent sequencing and identification of the microorganism in the majority of them.

PCR/LDR/universal array platforms for the diagnosis of infectious disease.

Science.gov (United States)

Pingle, Maneesh; Rundell, Mark; Das, Sanchita; Golightly, Linnie M; Barany, Francis

2010-01-01

Infectious diseases account for between 14 and 17 million deaths worldwide each year. Accurate and rapid diagnosis of bacterial, fungal, viral, and parasitic infections is therefore essential to reduce the morbidity and mortality associated with these diseases. Classical microbiological and serological methods have long served as the gold standard for diagnosis but are increasingly being replaced by molecular diagnostic methods that demonstrate increased sensitivity and specificity and provide an identification of the etiologic agent in a shorter period of time. PCR/LDR coupled with universal array detection provides a highly sensitive and specific platform for the detection and identification of bacterial and viral infections.

Microbiological soil regeneration

International Nuclear Information System (INIS)

Behrens, D.; Wiesner, J.

1992-01-01

The Interdiciplinary Task Force ''Environmental Biotechnology - Soil'' of DECHEMA aims to pool the knowledge potential of the Dechema study committees on environmental biotechnology and soil protection with a view to the advancement of microbiological soil decontamination techniques. This conference volume on the 9th expert meeting of Dechema on environmental protection subjects entitled ''Microbiological Soil Regeneration'', held on February 27th and 28th, 1991, and the subsequent compilation of results give an intermediate account of the ongoing work of the Dechema Task Force. (orig.) [de

Evolution across the Curriculum: Microbiology

Directory of Open Access Journals (Sweden)

Alita R. Burmeister

2016-05-01

Full Text Available An integrated understanding of microbiology and evolutionary biology is essential for students pursuing careers in microbiology and healthcare fields. In this Perspective, we discuss the usefulness of evolutionary concepts and an overall evolutionary framework for students enrolled in microbiology courses. Further, we propose a set of learning goals for students studying microbial evolution concepts. We then describe some barriers to microbial evolution teaching and learning and encourage the continued incorporation of evidence-based teaching practices into microbiology courses at all levels. Next, we review the current status of microbial evolution assessment tools and describe some education resources available for teaching microbial evolution. Successful microbial evolution education will require that evolution be taught across the undergraduate biology curriculum, with a continued focus on applications and applied careers, while aligning with national biology education reform initiatives.

One-step simultaneous detection of Ureaplasma parvum and genotypes SV1, SV3 and SV6 from clinical samples using PlexPCR technology.

Science.gov (United States)

Payne, M S; Furfaro, L L; Tucker, R; Tan, L Y; Mokany, E

2017-08-01

Ureaplasma spp. are associated with preterm birth. In recent times, it has become apparent that Ureaplasma parvum, but not Ureaplasma urealyticum, is of most relevance. We recently demonstrated this in Australian pregnant women and using high-resolution melt (HRM) PCR, further showed that U. parvum genotype SV6 was of particular significance. However, our assay was unable to identify multiple genotypes in the same sample, required a separate species-level qPCR for low titre samples and was not ideal for diagnostic laboratories due to the nature of HRM PCR result interpretation. Consequently, our current study developed a novel, one-step PlexPCR assay capable of detecting U. parvum and genotypes SV1, SV3 and SV6 in a single reaction directly from clinical samples. We then validated this using vaginal swab DNA from our Australian cohort of pregnant women. The PlexPCR was highly sensitive, detecting all targets to between 0.4 × 10 -5  ng DNA (SV3) and 0.4 × 10 -6  ng DNA (U. parvum, SV1 and SV6). Compared to our HRM PCR, the PlexPCR defined genotype distribution in all seven cases previously reported as 'mixed', and detected another eight cases where multiple genotypes (two) were present in samples previously reported as single genotypes using HRM PCR. Ureaplasma spp. have been associated with prematurity for decades, however, only a minority of studies have examined this beyond the genus level. In those that have, Ureaplasma parvum has been strongly associated with preterm birth. We recently demonstrated this in Australian women and further showed that U. parvum genotype SV6 was of particular significance. Our PlexPCR assay allows rapid detection and concurrent genotyping of U. parvum in clinical samples and may be of particular interest to obstetricians, particularly those caring for women at a high risk of preterm birth, and any other disease phenotypes where U. parvum is of interest. © 2017 The Authors. Letters in Applied Microbiology published by John

Current and Future Technologies for Microbiological Decontamination of Cereal Grains.

Science.gov (United States)

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®.

Effect of farmyard manure, mineral fertilizers and mung bean residues on some microbiological properties of eroded soil in district Swat

Directory of Open Access Journals (Sweden)

M. Naeem

2009-05-01

Full Text Available The present study was conducted to evaluate the efficacy of organic and inorganic fertilizers and mung bean residues on improving microbiological properties of eroded lands of District Swat, North West Frontier Province (NWFP Pakistan under wheat-mung bean-wheat cropping system during 2006 to 2008. The experiment was laid out in RCBD split-plot arrangement. Mung bean was grown and a basal dose of 25-60 kg N-P2O5 ha-1 was applied. After mung bean harvest, three residues management practices, i.e., R+ (mung bean residues incorporated into soil, R- (mung bean residues removed and F (fallow were performed in the main-plots. Sub-plot factor consisted of six fertilizer treatments for wheat crop i.e., T1 (control, T2 (120 kg N ha-1, T3 (120-90-0 kg N-P2O5-K2O ha-1, T4 (120-90-60 kg N-P2O5-K2O ha-1, T5 (90-90-60 kg N-P2O5-K2O + 10 t FYM ha-1 and T6 (60-90-60 kg N-P2O5- K2O + 20 t FYM ha-1. The results showed that microbial activity, microbial biomass-C and-N, mineralizable C and N were highest with T6 as well as with the incorporation of mung bean residues (R+. Compared with control, T6 increased microbial biomass C, N, mineralizable C and N by 33.8, 164.1, 35.5 and 110.6% at surface and 38.4, 237.5, 38.7 and 124.1% at sub-surface soil, respectively, while R+ compared with fallow increased these properties by 33.7, 47.4, 21.4 and 32.2% at surface and 36.8, 51, 21.9 and 35.4% at sub-surface soil, respectively. Inclusion of mung bean with its residues incorporated and application of 20 t FYM ha-1 and reducing inorganic N fertilizer to 60 kg N ha-1 for wheat is recommended for improving microbiological properties of slightly eroded lands

Comparative study of Gram stain, potassium hydroxide smear, culture and nested PCR in the diagnosis of fungal keratitis.

Science.gov (United States)

Badiee, Parisa; Nejabat, Mahmood; Alborzi, Abdolvahab; Keshavarz, Fatemeh; Shakiba, Elaheh

2010-01-01

This study seeks to evaluate the efficacy and practicality of the molecular method, compared to the standard microbiological techniques for diagnosing fungal keratitis (FK). Patients with eye findings suspected of FK were enrolled for cornea sampling. Scrapings from the affected areas of the infected corneas were obtained and were divided into two parts: one for smears and cultures, and the other for nested PCR analysis. Of the 38 eyes, 28 were judged to have fungal infections based on clinical and positive findings in the culture, smear and responses to antifungal treatment. Potassium hydroxide, Gram staining, culture and nested PCR results (either positive or negative) matched in 76.3, 42.1, 68.4 and 81.6%, respectively. PCR is a sensitive method but due to the lack of sophisticated facilities in routine laboratory procedures, it can serve only complementarily and cannot replace conventional methods. Copyright © 2010 S. Karger AG, Basel.

Clinical use of fungal PCR from deep tissue samples in the diagnosis of invasive fungal diseases: a retrospective observational study.

Science.gov (United States)

Ala-Houhala, M; Koukila-Kähkölä, P; Antikainen, J; Valve, J; Kirveskari, J; Anttila, V-J

2018-03-01

To assess the clinical use of panfungal PCR for diagnosis of invasive fungal diseases (IFDs). We focused on the deep tissue samples. We first described the design of panfungal PCR, which is in clinical use at Helsinki University Hospital. Next we retrospectively evaluated the results of 307 fungal PCR tests performed from 2013 to 2015. Samples were taken from normally sterile tissues and fluids. The patient population was nonselected. We classified the likelihood of IFD according to the criteria of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG), comparing the fungal PCR results to the likelihood of IFD along with culture and microscopy results. There were 48 positive (16%) and 259 negative (84%) PCR results. The sensitivity and specificity of PCR for diagnosing IFDs were 60.5% and 91.7%, respectively, while the negative predictive value and positive predictive value were 93.4% and 54.2%, respectively. The concordance between the PCR and the culture results was 86% and 87% between PCR and microscopy, respectively. Of the 48 patients with positive PCR results, 23 had a proven or probable IFD. Fungal PCR can be useful for diagnosing IFDs in deep tissue samples. It is beneficial to combine fungal PCR with culture and microscopy. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Molecular surveillance of true nontypeable Haemophilus influenzae: an evaluation of PCR screening assays.

Science.gov (United States)

Binks, Michael J; Temple, Beth; Kirkham, Lea-Ann; Wiertsema, Selma P; Dunne, Eileen M; Richmond, Peter C; Marsh, Robyn L; Leach, Amanda J; Smith-Vaughan, Heidi C

2012-01-01

Unambiguous identification of nontypeable Haemophilus influenzae (NTHi) is not possible by conventional microbiology. Molecular characterisation of phenotypically defined NTHi isolates suggests that up to 40% are Haemophilus haemolyticus (Hh); however, the genetic similarity of NTHi and Hh limits the power of simple molecular techniques such as PCR for species discrimination. Here we assess the ability of previously published and novel PCR-based assays to identify true NTHi. Sixty phenotypic NTHi isolates, classified by a dual 16S rRNA gene PCR algorithm as NTHi (n = 22), Hh (n = 27) or equivocal (n = 11), were further characterised by sequencing of the 16S rRNA and recA genes then interrogated by PCR-based assays targeting the omp P2, omp P6, lgtC, hpd, 16S rRNA, fucK and iga genes. The sequencing data and PCR results were used to define NTHi for this study. Two hpd real time PCR assays (hpd#1 and hpd#3) and the conventional iga PCR assay were equally efficient at differentiating study-defined NTHi from Hh, each with a receiver operator characteristic curve area of 0.90 [0.83; 0.98]. The hpd#1 and hpd#3 assays were completely specific against a panel of common respiratory bacteria, unlike the iga PCR, and the hpd#3 assay was able to detect below 10 copies per reaction. Our data suggest an evolutionary continuum between NTHi and Hh and therefore no single gene target could completely differentiate NTHi from Hh. The hpd#3 real time PCR assay proved to be the superior method for discrimination of NTHi from closely related Haemophilus species with the added potential for quantification of H. influenzae directly from specimens. We suggest the hpd#3 assay would be suitable for routine NTHi surveillance and to assess the impact of antibiotics and vaccines, on H. influenzae carriage rates, carriage density, and disease.

Molecular surveillance of true nontypeable Haemophilus influenzae: an evaluation of PCR screening assays.

Directory of Open Access Journals (Sweden)

Michael J Binks

Full Text Available BACKGROUND: Unambiguous identification of nontypeable Haemophilus influenzae (NTHi is not possible by conventional microbiology. Molecular characterisation of phenotypically defined NTHi isolates suggests that up to 40% are Haemophilus haemolyticus (Hh; however, the genetic similarity of NTHi and Hh limits the power of simple molecular techniques such as PCR for species discrimination. METHODOLOGY/PRINCIPAL FINDINGS: Here we assess the ability of previously published and novel PCR-based assays to identify true NTHi. Sixty phenotypic NTHi isolates, classified by a dual 16S rRNA gene PCR algorithm as NTHi (n = 22, Hh (n = 27 or equivocal (n = 11, were further characterised by sequencing of the 16S rRNA and recA genes then interrogated by PCR-based assays targeting the omp P2, omp P6, lgtC, hpd, 16S rRNA, fucK and iga genes. The sequencing data and PCR results were used to define NTHi for this study. Two hpd real time PCR assays (hpd#1 and hpd#3 and the conventional iga PCR assay were equally efficient at differentiating study-defined NTHi from Hh, each with a receiver operator characteristic curve area of 0.90 [0.83; 0.98]. The hpd#1 and hpd#3 assays were completely specific against a panel of common respiratory bacteria, unlike the iga PCR, and the hpd#3 assay was able to detect below 10 copies per reaction. CONCLUSIONS/SIGNIFICANCE: Our data suggest an evolutionary continuum between NTHi and Hh and therefore no single gene target could completely differentiate NTHi from Hh. The hpd#3 real time PCR assay proved to be the superior method for discrimination of NTHi from closely related Haemophilus species with the added potential for quantification of H. influenzae directly from specimens. We suggest the hpd#3 assay would be suitable for routine NTHi surveillance and to assess the impact of antibiotics and vaccines, on H. influenzae carriage rates, carriage density, and disease.

Impact of a Rapid Herpes Simplex Virus PCR Assay on Duration of Acyclovir Therapy.

Science.gov (United States)

Van, Tam T; Mongkolrattanothai, Kanokporn; Arevalo, Melissa; Lustestica, Maryann; Dien Bard, Jennifer

2017-05-01

Herpes simplex virus (HSV) infections of the central nervous system (CNS) are associated with significant morbidity and mortality rates in children. This study assessed the impact of a direct HSV (dHSV) PCR assay on the time to result reporting and the duration of acyclovir therapy for children with signs and symptoms of meningitis and encephalitis. A total of 363 patients with HSV PCR results from cerebrospinal fluid (CSF) samples were included in this retrospective analysis, divided into preimplementation and postimplementation groups. For the preimplementation group, CSF testing was performed using a laboratory-developed real-time PCR assay; for the postimplementation group, CSF samples were tested using a direct sample-to-answer assay. All CSF samples were negative for HSV. Over 60% of patients from both groups were prescribed acyclovir. The average HSV PCR test turnaround time for the postimplementation group was reduced by 14.5 h (23.6 h versus 9.1 h; P < 0.001). Furthermore, 79 patients (43.6%) in the postimplementation group had dHSV PCR results reported <4 h after specimen collection. The mean time from specimen collection to acyclovir discontinuation was 17.1 h shorter in the postimplementation group (31.1 h versus 14 h; P < 0.001). The median duration of acyclovir therapy was also significantly reduced in the postimplementation group (29.2 h versus 14.3 h; P = 0.01). Our investigation suggests that implementation of rapid HSV PCR testing can decrease turnaround times and the duration of unnecessary acyclovir therapy. Copyright © 2017 American Society for Microbiology.

African Journal of Clinical and Experimental Microbiology ...

African Journals Online (AJOL)

Author Guidelines. Aims and scope. African Journal of Clinical and Experimental Microbiology is the official Journal of African Society for Clinical Microbiology. It publishes original research papers in all aspects of Medical Microbiology, including Bacteriology, Virology Rickettsiology and Chlamydiology, Mycology, ...

Molecular Properties of Poliovirus Isolates: Nucleotide Sequence Analysis, Typing by PCR and Real-Time RT-PCR.

Science.gov (United States)

Burns, Cara C; Kilpatrick, David R; Iber, Jane C; Chen, Qi; Kew, Olen M

2016-01-01

Virologic surveillance is essential to the success of the World Health Organization initiative to eradicate poliomyelitis. Molecular methods have been used to detect polioviruses in tissue culture isolates derived from stool samples obtained through surveillance for acute flaccid paralysis. This chapter describes the use of realtime PCR assays to identify and serotype polioviruses. In particular, a degenerate, inosine-containing, panpoliovirus (panPV) PCR primer set is used to distinguish polioviruses from NPEVs. The high degree of nucleotide sequence diversity among polioviruses presents a challenge to the systematic design of nucleic acid-based reagents. To accommodate the wide variability and rapid evolution of poliovirus genomes, degenerate codon positions on the template were matched to mixed-base or deoxyinosine residues on both the primers and the TaqMan™ probes. Additional assays distinguish between Sabin vaccine strains and non-Sabin strains. This chapter also describes the use of generic poliovirus specific primers, along with degenerate and inosine-containing primers, for routine VP1 sequencing of poliovirus isolates. These primers, along with nondegenerate serotype-specific Sabin primers, can also be used to sequence individual polioviruses in mixtures.

MICROBIOLOGICAL QUALITY OF CONFECTIONARY PRODUCTS

Directory of Open Access Journals (Sweden)

Ľubomíra Juhaniaková

2013-02-01

Full Text Available The aim of this work was to determine microbiological quality of confectionery products. In confectionery products microbiological parameters: total count of bacteria, coliforms bacteria,mesophilic aerobes bacteria and microscopic filamentous fungi were observed. The confectionery products were evaluated: Kremeš and Venčekcake. For microbiological tests 20 samples of confectionery products were used. The numbers of total count of bacteria ranged from 3.29 log CFU.g-1, the number of mesophilic aerobes bacteria ranged from 1.86 to 2.85 log CFU.g-1, coliforms bacteria in confectionery products ranged from 0to 2.06CFU.g-1and the number of microscopic fungi ranged from 1.13 to 1.96CFU.g-1. The samples of cake prom private production showed better microbiological quality as samples from market production. All investigated samples of confectionary products were inaccordance with the Codex Alimentarius of the Slovak Republic.

Intra-Genomic Internal Transcribed Spacer Region Sequence Heterogeneity and Molecular Diagnosis in Clinical Microbiology.

Science.gov (United States)

Zhao, Ying; Tsang, Chi-Ching; Xiao, Meng; Cheng, Jingwei; Xu, Yingchun; Lau, Susanna K P; Woo, Patrick C Y

2015-10-22

Internal transcribed spacer region (ITS) sequencing is the most extensively used technology for accurate molecular identification of fungal pathogens in clinical microbiology laboratories. Intra-genomic ITS sequence heterogeneity, which makes fungal identification based on direct sequencing of PCR products difficult, has rarely been reported in pathogenic fungi. During the process of performing ITS sequencing on 71 yeast strains isolated from various clinical specimens, direct sequencing of the PCR products showed ambiguous sequences in six of them. After cloning the PCR products into plasmids for sequencing, interpretable sequencing electropherograms could be obtained. For each of the six isolates, 10-49 clones were selected for sequencing and two to seven intra-genomic ITS copies were detected. The identities of these six isolates were confirmed to be Candida glabrata (n=2), Pichia (Candida) norvegensis (n=2), Candida tropicalis (n=1) and Saccharomyces cerevisiae (n=1). Multiple sequence alignment revealed that one to four intra-genomic ITS polymorphic sites were present in the six isolates, and all these polymorphic sites were located in the ITS1 and/or ITS2 regions. We report and describe the first evidence of intra-genomic ITS sequence heterogeneity in four different pathogenic yeasts, which occurred exclusively in the ITS1 and ITS2 spacer regions for the six isolates in this study.

Rapid qualitative urinary tract infection pathogen identification by SeptiFast real-time PCR.

Directory of Open Access Journals (Sweden)

Lutz E Lehmann

2011-02-01

Full Text Available Urinary tract infections (UTI are frequent in outpatients. Fast pathogen identification is mandatory for shortening the time of discomfort and preventing serious complications. Urine culture needs up to 48 hours until pathogen identification. Consequently, the initial antibiotic regimen is empirical.To evaluate the feasibility of qualitative urine pathogen identification by a commercially available real-time PCR blood pathogen test (SeptiFast® and to compare the results with dipslide and microbiological culture.Pilot study with prospectively collected urine samples.University hospital.82 prospectively collected urine samples from 81 patients with suspected UTI were included. Dipslide urine culture was followed by microbiological pathogen identification in dipslide positive samples. In parallel, qualitative DNA based pathogen identification (SeptiFast® was performed in all samples.61 samples were SeptiFast® positive, whereas 67 samples were dipslide culture positive. The inter-methodological concordance of positive and negative findings in the gram+, gram- and fungi sector was 371/410 (90%, 477/492 (97% and 238/246 (97%, respectively. Sensitivity and specificity of the SeptiFast® test for the detection of an infection was 0.82 and 0.60, respectively. SeptiFast® pathogen identifications were available at least 43 hours prior to culture results.The SeptiFast® platform identified bacterial DNA in urine specimens considerably faster compared to conventional culture. For UTI diagnosis sensitivity and specificity is limited by its present qualitative setup which does not allow pathogen quantification. Future quantitative assays may hold promise for PCR based UTI pathogen identification as a supplementation of conventional culture methods.

[Post-mortem microbiology analysis].

Science.gov (United States)

Fernández-Rodríguez, Amparo; Alberola, Juan; Cohen, Marta Cecilia

2013-12-01

Post-mortem microbiology is useful in both clinical and forensic autopsies, and allows a suspected infection to be confirmed. Indeed, it is routinely applied to donor studies in the clinical setting, as well as in sudden and unexpected death in the forensic field. Implementation of specific sampling techniques in autopsy can minimize the possibility of contamination, making interpretation of the results easier. Specific interpretation criteria for post-mortem cultures, the use of molecular diagnosis, and its fusion with molecular biology and histopathology have led to post-mortem microbiology playing a major role in autopsy. Multidisciplinary work involving microbiologists, pathologists, and forensic physicians will help to improve the achievements of post-mortem microbiology, prevent infectious diseases, and contribute to a healthier population. Crown Copyright © 2012. Published by Elsevier Espana. All rights reserved.

Challenges in microbiological diagnosis of invasive Aspergillus infections [version 1; referees: 2 approved

Directory of Open Access Journals (Sweden)

Alexandre Alanio

2017-02-01

Full Text Available Invasive aspergillosis (IA has been increasingly reported in populations other than the historical hematology patients and there are new questions about the performance of microbiological tools. Microscopy and culture have been completed by biomarkers, either antigens or DNA, and in blood or respiratory specimens or both. First studied in hematology, the antigen galactomannan performance in serum is low in other patient populations where the pathophysiology of the infection can be different and the prevalence of IA is much lower. DNA detection with polymerase chain reaction (PCR in blood or serum (or both has reached a certain level of acceptance thanks to consensus methods based on real-time quantitative PCR (qPCR. When used on respiratory specimens, galactomannan and qPCR depend on standardization of the sampling and the diverse mycological procedures. Thus, culture remains the main diagnostic criterion in critically ill patients. The current trend toward more effective anti-mold prophylaxis in hematology hampers the yield of a screening strategy, as is usually performed in hematology. Therefore, circulating biomarkers as confirmatory tests should be considered and their performance should be reappraised in each new setting. The use of azole prophylaxis also raises the issue of selecting azole-resistance Aspergillus fumigatus isolates. Ideally, the biomarkers will be more efficient when individual genetic risks of IA are defined. Culture, though not standardized, remains a key element for the diagnosis of IA and has the advantage to easily detect molds other than A. fumigatus. It is still unclear whether next-generation sequencing will replace culture in the future.

Chemical and microbiological attributes of an oxisol treated with successive applications of sewage sludge¹

Directory of Open Access Journals (Sweden)

José Rafael Pires Bueno

2011-08-01

Full Text Available Studies on sewage sludge (SS have confirmed the possibilities of using this waste as fertilizer and/or soil conditioner in crop production areas. Despite restrictions with regard to the levels of potentially toxic elements (PTE and pathogens, it is believed that properly treated SS with low PTE levels, applied to soil at adequate rates, may improve the soil chemical and microbiological properties. This study consisted of a long-term field experiment conducted on a Typic Haplorthox (eutroferric Red Latosol treated with SS for seven successive years for maize production, to evaluate changes in the soil chemical and microbiological properties. The treatments consisted of two SS rates (single and double dose of the crop N requirement and a mineral fertilizer treatment. Soil was sampled in the 0-0.20 m layer and analyzed for chemical properties (organic C, pH, P, K, Ca, Mg, CEC, B, Cu, Fe, Mn, Zn, Cd, Ni, and Pb and microbiological properties (basal respiration, microbial biomass activity, microbial biomass C, metabolic quotient, microbial quotient, and protease and dehydrogenase enzyme activities. Successive SS applications to soil increased the macro- and micronutrient availability, but the highest SS dose reduced the soil pH significantly, indicating a need for periodic corrections. The SS treatments also affected soil microbial activity and biomass negatively. There were no significant differences among treatments for maize grain yield. After seven annual applications of the recommended sludge rate, the heavy metal levels in the soil had not reached toxic levels.

Rimsulfuron in Soil: Effects on Microbiological Properties under Varying Soil Conditions

Directory of Open Access Journals (Sweden)

Ljiljana Radivojević

2011-01-01

Full Text Available The effects of rimsulfuron a sulfonylurea herbicide on the growth and activity of soil microorganisms under laboratory conditions was investigated in two soils. The application rates were: 0.2, 2.0 and 20.0 mg a.i kg-1 soil. The lowest concentration tested was the label rate (0.2 mg a.i kg-1, and the other two were ten and hundred timeshigher. No adverse effects on microbiological processes were observed for the label rate. Decrease in microbial biomass carbon, dehydrogenase activity, fungi and bacteria in comparison with untreated control, were found at higher rates. The magnitude of these effects were generally slight and transitory.

Characterization of spoilage bacteria in pork sausage by PCR-DGGE analysis

Directory of Open Access Journals (Sweden)

Francesca Silva Dias

2013-09-01

Full Text Available To investigate microbial diversity and identify spoilage bacteria in fresh pork sausages during storage, twelve industrial pork sausages of different trademarks were stored at 4 ºC for 0, 14, 28 and 42 days, 80% relative humidity and packaged in sterile plastic bags. Microbiological analysis was performed. The pH and water activity (a w were measured. The culture-independent method performed was the Polymerase Chain Reaction - Denaturing Gradient Gel Electrophoresis (PCR-DGGE. The culture-dependent method showed that the populations of mesophilic bacteria and Lactic Acid Bacteria (LAB increased linearly over storage time. At the end of the storage time, the average population of microorganisms was detected, in general, at the level of 5 log cfu g-1. A significant (P < 0.005 increase was observed in pH and a w values at the end of the storage time. The PCR-DGGE allowed a rapid identification of dominant communities present in sausages. PCR-DGGE discriminated 15 species and seven genera of bacteria that frequently constitute the microbiota in sausage products. The most frequent spoilage bacteria identified in the sausages were Lactobacillus sakei and Brochothrix thermosphacta. The identification of dominant communities present in fresh pork sausages can help in the choice of the most effective preservation method for extending the product shelf-life.

High-pressure microbiology

National Research Council Canada - National Science Library

Michiels, Chris; Bartlett, Douglas Hoyt; Aertsen, Abram

2008-01-01

... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1. High Hydrostatic Pressure Effects in the Biosphere: from Molecules to Microbiology * Filip Meersman and Karel Heremans . . . . . . . . . . . . 2. Effects...

Determining the potential link between irrigation water quality and the microbiological quality of onions by phenotypic and genotypic characterization of Escherichia coli isolates.

Science.gov (United States)

du Plessis, Erika M; Duvenage, Francois; Korsten, Lise

2015-04-01

The potential transfer of human pathogenic bacteria present in irrigation water onto fresh produce was investigated, because surface water sources used for irrigation purposes in South Africa have increasingly been reported to be contaminated with enteric bacterial pathogens. A microbiological analysis was performed of a selected river in Limpopo Province, South Africa, that is often contaminated with raw sewage from municipal sewage works and overhead irrigated onions produced on a commercial farm. Counts of Escherichia coli, coliforms, aerobic bacteria, fungi, and yeasts and the prevalence of E. coli O157:H7, Salmonella, and Listeria monocytogenes were determined. Identities of bacterial isolates from irrigation water and onions were confirmed using matrix-assisted laser desorption ionization-time of flight mass spectrometry, PCR, and biochemical tests. To establish a potential link between the microbiological quality of the irrigation source and the onions, the E. coli isolates from both were subjected to antibiotic resistance, virulence gene, and enterobacterial repetitive intergenic consensus PCR analyses. River water E. coli counts exceeded South African Department of Water Affairs and World Health Organization irrigation water guidelines. Counts of aerobic bacteria, coliforms, fungi, and yeasts of onions from the market were acceptable according to Department of Health Directorate, Food Control, South Africa, microbiological guidelines for ready-to-eat fresh fruits and vegetables. E. coli O157:H7, Salmonella, and L. monocytogenes were not detected in onions, whereas only Salmonella was detected in 22% of water samples. Matrix-assisted laser desorption ionization-time of flight mass spectrometry and PCR identification of E. coli isolates from water and onions correlated. Of the 45 E. coli isolates from water and onions, 42.2% were resistant to multiple antibiotics. Virulence genes eae, stx1, and stx2 were detected in 2.2, 6.6, and 2.2% of the E. coli isolates

Quantitative Microbiological Study of Human Carious Dentine by Culture and Real-Time PCR: Association of Anaerobes with Histopathological Changes in Chronic Pulpitis

Science.gov (United States)

Martin, F. Elizabeth; Nadkarni, Mangala A.; Jacques, Nicholas A.; Hunter, Neil

2002-01-01

The bacteria found in carious dentine were correlated with the tissue response of the dental pulps of 65 teeth extracted from patients with advanced caries and pulpitis. Standardized homogenates of carious dentine were plated onto selective and nonselective media under anaerobic and microaerophilic conditions. In addition, real-time PCR was used to quantify the recovery of anaerobic bacteria. Primers and fluorogenic probes were designed to detect the total anaerobic microbial load, the genera Prevotella and Fusobacterium, and the species Prevotella melaninogenica, Porphyromonas endodontalis, Porphyromonas gingivalis, and Micromonas (formerly Peptostreptococcus) micros. The pulpal pathology was categorized according to the cellular response and degenerative changes. Analysis of cultured bacteria showed a predominance of gram-positive microorganisms, particularly lactobacilli. Gram-negative bacteria were also present in significant numbers with Prevotella spp., the most numerous anaerobic group cultured. Real-time PCR analysis indicated a greater microbial load than that determined by colony counting. The total number of anaerobes detected was 41-fold greater by real-time PCR than by colony counting, while the numbers of Prevotella and Fusobacterium spp. detected were 82- and 2.4-fold greater by real-time PCR than by colony counting, respectively. Real-time PCR also identified M. micros, P. endodontalis, and P. gingivalis in 71, 60, and 52% of carious samples, respectively. Correlation matrices of the real-time PCR data revealed significant positive associations between M. micros and P. endodontalis detection and inflammatory degeneration of pulpal tissues. These anaerobes have been strongly implicated in endodontic infections that occur as sequelae to carious pulpitis. Accordingly, the data suggest that the presence of high levels of these bacteria in carious lesions may be indicative of irreversible pulpal pathology. PMID:11980945

Microbiology, philosophy and education.

Science.gov (United States)

O'Malley, Maureen A

2016-09-01

There are not only many links between microbiological and philosophical topics, but good educational reasons for microbiologists to explore the philosophical issues in their fields. I examine three broad issues of classification, causality and model systems, showing how these philosophical dimensions have practical implications. I conclude with a discussion of the educational benefits for recognising the philosophy in microbiology. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Effect of gamma irradiation on microbiological, chemical, and sensory properties of fresh ashitaba and kale juices

International Nuclear Information System (INIS)

Jo, Cheorun; Ahn, Dong Uk; Lee, Kyung Haeng

2012-01-01

Due to the popularity of health effects upon intake of fresh fruits and vegetables, the demand for fresh vegetables and fruit juices has rapidly increased. However, currently, washing is the only procedure for reducing contaminated microorganisms, which obviously limits the shelf-life of fresh vegetable juice (less than 3 days). In this study, we examined the effects of irradiation on the microbiological, chemical and sensory properties of ashitaba and kale juices for industrial application and possible shelf-life extension. Freshly made ashitaba and kale juices already had 2.3×10 5 and 9.5×10 4 CFU/mL, respectively. Irradiation of 5 kGy induced higher than 2 decimal reductions in the microbial level, which was consistently maintained during storage for 7 days under refrigerated conditions. Total content of ascorbic acid in vegetable juice decreased upon irradiation in a dose-dependent manner. However, the content of flavonoids did not change, whereas that of polyphenols increased upon irradiation. In sensory evaluation, the ashitaba and kale juices without irradiation (control) scored lower than the irradiated samples after 1 and 3 days, respectively. This study confirms that irradiation is an effective method for sterilizing fresh vegetable juice without compromising sensory property, which cannot be subjected to heat pasteurization due to changes in the bioactivities of the products. - Highlights: ► We examined the effects of irradiation of fresh vegetable juices (ashitaba and kale) for industrial application. ► Irradiation of 5 kGy induced higher than 2 decimal reductions in the microbial level. ► Ascorbic acid in vegetable juice decreased upon irradiation in a dose-dependent manner. ► Content of flavonoids did not change whereas that of polyphenols increased. ► There was no change in sensory properties after irradiation.

Development of a One-Step Multiplex PCR Assay for Differential Detection of Major Mycobacterium Species.

Science.gov (United States)

Chae, Hansong; Han, Seung Jung; Kim, Su-Young; Ki, Chang-Seok; Huh, Hee Jae; Yong, Dongeun; Koh, Won-Jung; Shin, Sung Jae

2017-09-01

The prevalence of tuberculosis continues to be high, and nontuberculous mycobacterial (NTM) infection has also emerged worldwide. Moreover, differential and accurate identification of mycobacteria to the species or subspecies level is an unmet clinical need. Here, we developed a one-step multiplex PCR assay using whole-genome analysis and bioinformatics to identify novel molecular targets. The aims of this assay were to (i) discriminate between the Mycobacterium tuberculosis complex (MTBC) and NTM using rv0577 or RD750, (ii) differentiate M. tuberculosis ( M. tuberculosis ) from MTBC using RD9, (iii) selectively identify the widespread M. tuberculosis Beijing genotype by targeting mtbk_20680 , and (iv) simultaneously detect five clinically important NTM ( M. avium , M. intracellulare , M. abscessus , M. massiliense , and M. kansasii ) by targeting IS 1311 , DT1, mass_3210 , and mkan_rs12360 An initial evaluation of the multiplex PCR assay using reference strains demonstrated 100% specificity for the targeted Mycobacterium species. Analytical sensitivity ranged from 1 to 10 pg for extracted DNA and was 10 3 and 10 4 CFU for pure cultures and nonhomogenized artificial sputum cultures, respectively, of the targeted species. The accuracy of the multiplex PCR assay was further evaluated using 55 reference strains and 94 mycobacterial clinical isolates. Spoligotyping, multilocus sequence analysis, and a commercial real-time PCR assay were employed as standard assays to evaluate the multiplex PCR assay with clinical M. tuberculosis and NTM isolates. The PCR assay displayed 100% identification agreement with the standard assays. Our multiplex PCR assay is a simple, convenient, and reliable technique for differential identification of MTBC, M. tuberculosis , M. tuberculosis Beijing genotype, and major NTM species. Copyright © 2017 American Society for Microbiology.

In vitro adhesion and anti-inflammatory properties of native Lactobacillus fermentum and Lactobacillus delbrueckii spp.

Science.gov (United States)

Archer, A C; Kurrey, N K; Halami, P M

2018-03-14

This study aimed at characterizing the adhesion and immune-stimulatory properties of native probiotic Lactobacillus fermentum (MCC 2759 and MCC 2760) and Lactobacillus delbrueckii MCC 2775. Adhesion of the strains was assessed in Caco-2 and HT-29 cell lines. Expression of adhesion and immune markers were evaluated in Caco-2 cells by real-time qPCR. The cultures displayed >80% of adhesion to both cell lines and also induced the expression of mucin-binding protein (mub) gene in the presence of mucin, bile and pancreatin. Adhesion was mediated by carbohydrate and proteinaceous factors. The cultures stimulated the expression of inflammatory cytokines in Caco-2 cells. However, pro-inflammatory genes were down-regulated upon challenge with lipopolysaccharide and IL-10 was up-regulated by the cultures. Cell wall extract of L. fermentum MCC 2760 induced the expression of IL-6 by 5·47-fold, whereas crude culture filtrate enhanced the expression of IL-10 by 14·87-fold compared to LPS control. The bacterial cultures exhibited strong adhesion and anti-inflammatory properties. This is the first report to reveal the role of adhesion markers of L. fermentum and L. delbrueckii by qPCR. The strain-specific anti-inflammatory property of native cultures may be useful to alleviate inflammatory conditions and develop a target-based probiotic. © 2018 The Society for Applied Microbiology.

Design of a species-specific PCR method for the detection of the heat-resistant fungi Talaromyces macrosporus and Talaromyces trachyspermus.

Science.gov (United States)

Yamashita, S; Nakagawa, H; Sakaguchi, T; Arima, T-H; Kikoku, Y

2018-01-01

Heat-resistant fungi occur sporadically and are a continuing problem for the food and beverage industry. The genus Talaromyces, as a typical fungus, is capable of producing the heat-resistant ascospores responsible for the spoilage of processed food products. Isocitrate lyase, a signature enzyme of the glyoxylate cycle, is required for the metabolism of non-fermentable carbon compounds, like acetate and ethanol. Here, species-specific primer sets for detection and identification of DNA derived from Talaromyces macrosporus and Talaromyces trachyspermus were designed based on the nucleotide sequences of their isocitrate lyase genes. Polymerase chain reaction (PCR) using a species-specific primer set amplified products specific to T. macrosporus and T. trachyspermus. Other fungal species, such as Byssochlamys fulva and Hamigera striata, which cause food spoilage, were not detected using the Talaromyces-specific primer sets. The detection limit for each species-specific primer set was determined as being 50 pg of template DNA, without using a nested PCR method. The specificity of each species-specific primer set was maintained in the presence of 1,000-fold amounts of genomic DNA from other fungi. The method also detected fungal DNA extracted from blueberry inoculated with T. macrosporus. This PCR method provides a quick, simple, powerful and reliable way to detect T. macrosporus and T. trachyspermus. Polymerase chain reaction (PCR)-based detection is rapid, convenient and sensitive compared with traditional methods of detecting heat-resistant fungi. In this study, a PCR-based method was developed for the detection and identification of amplification products from Talaromyces macrosporus and Talaromyces trachyspermus using primer sets that target the isocitrate lyase gene. This method could be used for the on-site detection of T. macrosporus and T. trachyspermus in the near future, and will be helpful in the safety control of raw materials and in food and beverage

Real-time PCR to supplement gold-standard culture-based detection of Legionella in environmental samples.

Science.gov (United States)

Collins, S; Jorgensen, F; Willis, C; Walker, J

2015-10-01

Culture remains the gold-standard for the enumeration of environmental Legionella. However, it has several drawbacks including long incubation and poor sensitivity, causing delays in response times to outbreaks of Legionnaires' disease. This study aimed to validate real-time PCR assays to quantify Legionella species (ssrA gene), Legionella pneumophila (mip gene) and Leg. pneumophila serogroup-1 (wzm gene) to support culture-based detection in a frontline public health laboratory. Each qPCR assay had 100% specificity, excellent sensitivity (5 GU/reaction) and reproducibility. Comparison of the assays to culture-based enumeration of Legionella from 200 environmental samples showed that they had a negative predictive value of 100%. Thirty eight samples were positive for Legionella species by culture and qPCR. One hundred samples were negative by both methods, whereas 62 samples were negative by culture but positive by qPCR. The average log10 increase between culture and qPCR for Legionella spp. and Leg. pneumophila was 0·72 (P = 0·0002) and 0·51 (P = 0·006), respectively. The qPCR assays can be conducted on the same 1 l water sample as culture thus can be used as a supplementary technique to screen out negative samples and allow more rapid indication of positive samples. The assay could prove informative in public health investigations to identify or rule out sources of Legionella as well as to specifically identify Leg. pneumophila serogroup 1 in a timely manner not possible with culture. © 2015 The Society for Applied Microbiology.

A validation of the Danish microbiology database (MiBa) and incidence rate of Actinotignum schaalii (Actinobaculum schaalii) bacteraemia in Denmark.

Science.gov (United States)

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.

Diagnosis of bacteremia in pediatric oncologic patients by in-house real-time PCR.

Science.gov (United States)

Quiles, Milene Gonçalves; Menezes, Liana Carballo; Bauab, Karen de Castro; Gumpl, Elke Kreuscher; Rocchetti, Talita Trevizani; Palomo, Flavia Silva; Carlesse, Fabianne; Pignatari, Antonio Carlos Campos

2015-07-23

Infections are the major cause of morbidity and mortality in children with cancer. Gaining a favorable prognosis for these patients depends on selecting the appropriate therapy, which in turn depends on rapid and accurate microbiological diagnosis. This study employed real-time PCR (qPCR) to identify the main pathogens causing bloodstream infection (BSI) in patients treated at the Pediatric Oncology Institute IOP-GRAACC-UNIFESP-Brazil. Antimicrobial resistance genes were also investigated using this methodology. A total of 248 samples from BACTEC® blood culture bottles and 99 whole-blood samples collected in tubes containing EDTA K2 Gel were isolated from 137 patients. All samples were screened by specific Gram probes for multiplex qPCR. Seventeen sequences were evaluated using gender-specific TaqMan probes and the resistance genes bla SHV, bla TEM, bla CTX, bla KPC, bla IMP, bla SPM, bla VIM, vanA, vanB and mecA were detected using the SYBR Green method. Positive qPCR results were obtained in 112 of the blood culture bottles (112/124), and 90 % agreement was observed between phenotypic and molecular microbial detection methods. For bacterial and fungal identification, the performance test showed: sensitivity 87 %; specificity 91 %; NPV 90 %; PPV 89 % and accuracy of 89 % when compared with the phenotypic method. The mecA gene was detected in 37 samples, extended-spectrum β-lactamases were detected in six samples and metallo-β-lactamase coding genes in four samples, with 60 % concordance between the two methods. The qPCR on whole blood detected eight samples possessing the mecA gene and one sample harboring the vanB gene. The bla KPC, bla VIM, bla IMP and bla SHV genes were not detected in this study. Real-time PCR is a useful tool in the early identification of pathogens and antimicrobial resistance genes from bloodstream infections of pediatric oncologic patients.

Effect of plant extracts Kitaibelia vitifolia on antioxidant activity, chemical characteristics, microbiological status and sensory properties of Pirotski kachkaval cheese

Directory of Open Access Journals (Sweden)

Kurćubić Vladimir S.

2015-01-01

Full Text Available The aim of our study was to evaluate the impact of cheese (Pirotski kachkaval fortification by polyphenols attributed to Kitaibelia vitifolia ethanol herb extract, applied in two different manners (added to the cheese curd after texturizing or sprayed on surface of cheese. Investigation of the used antioxidant effects of polyphenols, physic-chemical composition, microbiological quality and sensory properties of Pirotski kachkaval was undertaken. Antioxidant activity of conventional and fortified cheese was evaluated by five contemporary and compatible methods, and revealed a slight emphasis on phenol-linked antioxidant activity of fortified samples of cheese in comparison to samples of the control group. Fortified Pirotski kachkaval had higher sensory evaluation scores than the controls. Statistically significant (P 0.05. [Projekat Ministarstva nauke Republike Srbije, br. III 46009 i br. OI 172016

Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia and Prevotella nigrescens in endodontic lesions detected by culture and by PCR.

Science.gov (United States)

Gomes, B P F A; Jacinto, R C; Pinheiro, E T; Sousa, E L R; Zaia, A A; Ferraz, C C R; Souza-Filho, F J

2005-08-01

he aim of this study was to investigate the presence of four black-pigmented bacteria, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia and Prevotella nigrescens, in endodontic infections by culture and polymerase chain reaction (PCR) analyses. Microbial samples were obtained from 50 teeth with untreated necrotic pulps (primary infection) and from 50 teeth with failing endodontic treatment (secondary infection). Microbiological strict anaerobic techniques were used for serial dilution, plating, incubation, and identification. For PCR detection, the samples were analyzed using species-specific primers of 16S rDNA and the downstream intergenic spacer region. Culture and PCR detected the test species in 13/100 and 50/100 of the study teeth, respectively. The organisms were cultured from 11/50 (22%) of primarily infected root canal samples and from 2/50 (4%) of secondary root canal samples. PCR detection identified the target species in 32/50 (64%) and 18/50 (36%) of primary and secondary infections, respectively. P. gingivalis was rarely isolated by culture methods (1%), but was the most frequently identified test species by PCR (38%). Similarly, P. endodontalis was not recovered by culture from any tooth studied, but was detected by PCR in 25% of the sampled teeth. PCR-based identification also showed higher detection rates of P. intermedia (33%) and P. nigrescens (22%) than culture (13%). In conclusion, P. gingivalis, P. endodontalis, P. intermedia, and P. nigrescens were identified more frequently in teeth with necrotic pulp than in teeth with failing endodontic treatment. Also, a higher frequency of black-pigmented species was detected by PCR than by culture.

Building a Portuguese Food Microbiological Information Network

OpenAIRE

Viegas, Silvia; Machado, Claudia; Dantas, Maria; Oliveira, Luísa

2011-01-01

Introduction: The integration of food data from research, microbiological monitoring, epidemiological investigation and disease surveillance is crucial to manage foodborne risk. Consequently, INSA launched the Portuguese Food Information Resource Programme (PortFIR) in a partnership with GS1 Portugal to create national food chain expert networks and sustainable databases on food composition, consumption and chemical and microbiological contamination. Presently, the Food Microbiological Inform...

[Tropheryma whipplei and Whipple disease: false positive PCR detections of Tropheryma whipplei in diagnostic samples are rare].

Science.gov (United States)

Le Scanff, J; Gaultier, J B; Durand, D Vital; Durieu, I; Celard, M; Benito, Y; Vandenesch, F; Rousset, H

2008-11-01

PCR can be used to detect T. whipplei (Tw) in samples from variable tissue types and body fluids. We report clinical, evolutive characteristics and final diagnosis in patients with positive Tw PCR assay. Retrospective study of Tw PCR realized since 10years in a microbiology laboratory. Twenty-five Tw PCR assays were positive among 200 realized. Diagnosis was not confirmed in six cases. One patient was missing for follow up. Eighteen patients presented with Whipple's disease. Among these 18 patients, 14 had a classic Whipple's disease, three patients presented an endocarditis and one patient isolated neurological manifestations. Ten patients presented fever, seven a weight loss and 12 joint involvement. Four patients presented cutaneous manifestations, only six had gastrointestinal symptoms. Neurological involvement was reported in five cases, pulmonary symptoms in four cases, cardiac involvement in six cases and ocular signs in two cases. Anemia was reported in four patients and elevated levels of acute-phase reactants in 14 cases. Positive predictive value of Tw PCR for Whipple's disease diagnosis was 75%. Thirteen patients had a good evolution with antibiotics. Three patients presented recurrence and two cases with cardiovascular involvement died. Whipple's disease is rare but often mentioned in internist experience. The diagnosis should be every time confirmed. Tw PCR assay is an important diagnostic tool but is not sufficient to establish the diagnosis and must be interpreted with histopathology and immunohistochemical testing results.

ANALYTICAL MICROBIOLOGY LABORATORY

Data.gov (United States)

Federal Laboratory Consortium — This laboratory contains equipment that performs a broad array of microbiological analyses for pathogenic and spoilage microorganisms. It performs challenge studies...

16S pan-bacterial PCR can accurately identify patients with ventilator-associated pneumonia.

Science.gov (United States)

Conway Morris, Andrew; Gadsby, Naomi; McKenna, James P; Hellyer, Thomas P; Dark, Paul; Singh, Suveer; Walsh, Timothy S; McAuley, Danny F; Templeton, Kate; Simpson, A John; McMullan, Ronan

2017-11-01

Ventilator-associated pneumonia (VAP) remains a challenge to intensive care units, with secure diagnosis relying on microbiological cultures that take up to 72 hours to provide a result. We sought to derive and validate a novel, real-time 16S rRNA gene PCR for rapid exclusion of VAP. Bronchoalveolar lavage (BAL) was obtained from two independent cohorts of patients with suspected VAP. Patients were recruited in a 2-centre derivation cohort and a 12-centre confirmation cohort. Confirmed VAP was defined as growth of >10 4 colony forming units/ml on semiquantitative culture and compared with a 16S PCR assay. Samples were tested from 67 patients in the derivation cohort, 10 (15%) of whom had confirmed VAP. Using cycles to cross threshold (C t ) values as the result of the 16S PCR test, the area under the receiver operating characteristic (ROC) curve (AUROC) was 0.94 (95% CI 0.86 to 1.0, p<0.0001). Samples from 92 patients were available from the confirmation cohort, 26 (28%) of whom had confirmed VAP. The AUROC for C t in this cohort was 0.89 (95% CI 0.83 to 0.95, p<0.0001). This study has derived and assessed the diagnostic accuracy of a novel application for 16S PCR. This suggests that 16S PCR in BAL could be used as a rapid test in suspected VAP and may allow better stewardship of antibiotics. VAPRAPID trial ref NCT01972425. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Detection of Histoplasma capsulatum in Organic Fertilizers by Hc100 Nested Polymerase Chain Reaction and Its Correlation with the Physicochemical and Microbiological Characteristics of the Samples.

Science.gov (United States)

Gómez, Luisa F; Torres, Isaura P; Jiménez-A, María Del Pilar; McEwen, Juan Gmo; de Bedout, Catalina; Peláez, Carlos A; Acevedo, José M; Taylor, María L; Arango, Myrtha

2018-05-01

Histoplasma capsulatum is the causative agent of histoplasmosis and this fungus inhabits soils rich in phosphorus and nitrogen that are enriched with bird and bat manure. The replacement of organic matter in agroecosystems is necessary in the tropics, and the use of organic fertilizers has increased. Cases and outbreaks due to the presence of the fungus in these components have been reported. The Instituto Colombiano Agropecuario resolution 150 of 2003 contains the parameters set by the Colombian Technical Standard (NTC 5167) on the physicochemical and microbiological features of fertilizers, but it does not regulate the search for H. capsulatum . The aim of this study was to demonstrate H. capsulatum presence in organic fertilizers by nested polymerase chain reaction (PCR). A total of 239 samples were collected: 201 (84.1%) corresponded to organic fertilizers, 30 (12.5%) to bird excrement, and 8 (3.4%) to cave soils. The Hc100 nested PCR had a detection limit of 0.1 pg/µL and a specificity of 100%. A total of 25 (10.5%) samples were positive and validated by sequencing. Seven of the positive samples represented locations where H. capsulatum was previously detected, suggesting the persistence of the fungus. No significant correlations were detected between the physicochemical and microbiological parameters with the presence of H. capsulatum by nested PCR, indicating the fungus existence in organic fertilizers that complied with the NTC 5167. The Hc100 nested PCR targeting H. capsulatum standardized in this work will improve the evaluation of organic fertilizers and ensure the prevention of outbreaks and cases due to manufacturing, marketing, and use of fertilizers contaminated with H. capsulatum .

Environmental Microbiology Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Environmental Microbiology Laboratory, located in Bldg. 644 provides a dual-gas respirometer for measurement of oxygen consumption and carbon dioxide evolution...

Microbiological aspects of safety in radioactive waste management

International Nuclear Information System (INIS)

Ershov, B.G.; Safonov, A.V.; Nazina, T.N.; Gorbunova, O.A.

2012-01-01

In long-term storage and/or disposal of radioactive waste, microbiological processes play an important, and in some cases a vital role. The article discusses the issues of microbiological processes in underground liquid LLW repositories and microbiological destruction of cemented radwaste. It is shown that biological additives to cement matrices can be used to effectively prevent the occurrence of microbiological processes, increasing reliability of engineering barriers that block release of radionuclides into the areas adjacent to the repositories [ru

Development of a multiplex PCR assay for rapid and simultaneous detection of four genera of fish pathogenic bacteria.

Science.gov (United States)

Zhang, D F; Zhang, Q Q; Li, A H

2014-11-01

Species of genus Aeromonas, Vibrio, Edwardsiella and Streptococcus are the most common fish pathogenic bacteria that cause economically devastating losses in aquaculture. A multiplex polymerase chain reaction (mPCR) was developed for the simultaneous detection and differentiation of the four genera of fish pathogenic bacteria. Through the use of genus-specific primers instead of species-specific ones, the current mPCR covered much more target bacterial species compared with previously reported species-specific mPCR methods. The specificity of the four putative genus-specific primers was validated experimentally while used exclusively (uniplex PCR) or combined (mPCR) against bacterial genomic DNA templates of the target bacteria and nontarget bacteria. The PCR amplicons for the following genera were obtained as expected: Aeromonas (875 bp), Vibrio (524 bp), Edwardsiella (302 bp) and Streptococcus (197 bp), and the fragments could be separated clearly on the agarose gel electrophoresis. The mPCR did not produce nonspecific amplification products when used to amplify 21 nontarget species of bacteria. The mPCR detection limits for each target bacterial genera were 50 colony-forming units (CFU) in pure culture and 100 CFU in fish tissue samples. In conclusion, the mPCR assay was proven to be a powerful alternative to the conventional culture-based method, given its rapid, specific, sensitive and reliable detection of target pathogens. The fish pathogenic bacteria of genus Aeromonas, Vibrio, Edwardsiella and Streptococcus frequently cause severe outbreaks of diseases in cultured fish, and the genus-specific multiplex PCR assay developed in this study can detect the bacteria of the four genera when present in the samples either alone or mixed. The mPCR assay is expected to identify the causative agents more efficiently than uniplex PCR or species-specific multiplex PCR for clinical diagnosis, resulting in the earlier implementation of control measures. This mPCR

Tillage system affects microbiological properties of soil

Science.gov (United States)

Delgado, A.; de Santiago, A.; Avilés, M.; Perea, F.

2012-04-01

Soil tillage significantly affects organic carbon accumulation, microbial biomass, and subsequently enzymatic activity in surface soil. Microbial activity in soil is a crucial parameter contributing to soil functioning, and thus a basic quality factor for soil. Since enzymes remain soil after excretion by living or disintegrating cells, shifts in their activities reflect long-term fluctuations in microbial biomass. In order to study the effects of no-till on biochemical and microbiological properties in comparison to conventional tillage in a representative soil from South Spain, an experiment was conducted since 1982 on the experimental farm of the Institute of Agriculture and Fisheries Research of Andalusia (IFAPA) in Carmona, SW Spain (37o24'07''N, 5o35'10''W). The soil at the experimental site was a very fine, montomorillonitic, thermic Chromic Haploxerert (Soil Survey Staff, 2010). A randomized complete block design involving three replications and the following two tillage treatments was performed: (i) Conventional tillage, which involved mouldboard plowing to a depth of 50 cm in the summer (once every three years), followed by field cultivation to a depth of 15 cm before sowing; crop residues being burnt, (ii) No tillage, which involved controlling weeds before sowing by spraying glyphosate and sowing directly into the crop residue from the previous year by using a planter with double-disk openers. For all tillage treatments, the crop rotation (annual crops) consisted of winter wheat, sunflower, and legumes (pea, chickpea, or faba bean, depending on the year), which were grown under rainfed conditions. Enzymatic activities (ß-glucosidase, dehydrogenase, aryl-sulphatase, acid phosphatase, and urease), soil microbial biomass by total viable cells number by acridine orange direct count, the density of cultivable groups of bacteria and fungi by dilution plating on semi-selective media, the physiological profiles of the microbial communities by BiologR, and the

Pulmonary toxoplasmosis in immunocompromised patients with interstitial pneumonia: a single-centre prospective study assessing PCR-based diagnosis.

Science.gov (United States)

Desoubeaux, Guillaume; Cabanne, Églantine; Franck-Martel, Claire; Gombert, Martin; Gyan, Emmanuel; Lissandre, Séverine; Renaud, Marc; Monjanel, Hélène; Dartigeas, Caroline; Bailly, Éric; Van Langendonck, Nathalie; Chandenier, Jacques

2016-08-01

Pulmonary toxoplasmosis has become a very rare parasitic infection since the advent of highly active antiretroviral therapies. It is generally diagnosed by the direct microscopic observation of Toxoplasma gondii tachyzoites in bronchoalveolar lavage fluid (BALF). The aim of this study was to assess possible improvements in diagnostic performance associated with the use of real-time PCR. This prospective study was carried out on BALFs obtained from immunocompromised patients over a 2-year period. We systematically compared the results of conventional staining with those of molecular detection. Two cases of pulmonary toxoplasmosis were diagnosed for a total of 336 samples. PCR did not detect any additional cases and was more time-consuming than conventional staining. Conventional staining is a reliable technique and is probably the most appropriate method for experienced microbiology laboratories, whereas T. gondii-specific PCR may be useful for laboratories with less experience in parasitology. 2015_030, May 27th 2015. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Comparison of Sensory Properties, Shelf-Life and Microbiological Safety of Industrial Sausages Produced with Autochthonous and Commercial Starter Cultures

Directory of Open Access Journals (Sweden)

Jadranka Frece

2014-01-01

Full Text Available The aim of this research is to use isolated and characterized autochthonous functional starter cultures from traditional Croatian dry sausages and to evaluate their capacity for industrial production of five sausages (Čajna sausage, Zimska sausage, Bečka sausage, Srijemska sausage and Slavonski kulen. These defined autochthonous functional starter cultures (combination of Lactobacillus and Staphylococcus strains were used to produce five different industrial sausages which were compared by a panel. The viability of introduced autochthonous Lactobacillus and Staphylococcus strains and their effect on the final product characteristics, namely microbiological, physicochemical and sensory properties were monitored. The obtained results indicate that autochthonous starter cultures survived industrial production of sausages and can be used for production of sausages under controlled conditions. Autochthonous starter cultures obtained better results in the organoleptic evaluation, microbial safety and prolonged shelf-life in comparison with commercial starter cultures.

High-throughput multiplex real-time PCR assay for the simultaneous quantification of DNA and RNA viruses infecting cassava plants.

Science.gov (United States)

Otti, G; Bouvaine, S; Kimata, B; Mkamillo, G; Kumar, P L; Tomlins, K; Maruthi, M N

2016-05-01

To develop a multiplex TaqMan-based real-time PCR assay (qPCR) for the simultaneous detection and quantification of both RNA and DNA viruses affecting cassava (Manihot esculenta) in eastern Africa. The diagnostic assay was developed for two RNA viruses; Cassava brown streak virus (CBSV) and Uganda cassava brown streak virus (UCBSV) and two predominant DNA viruses; African cassava mosaic virus (ACMV) and East African cassava mosaic virus (EACMV), which cause the economically important cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) respectively. Our method, developed by analysing PCR products of viruses, was highly sensitive to detect target viruses from very low quantities of 4-10 femtograms. Multiplexing did not diminish sensitivity or accuracy compared to uniplex alternatives. The assay reliably detected and quantified four cassava viruses in field samples where CBSV and UCBSV synergy was observed in majority of mixed-infected varieties. We have developed a high-throughput qPCR diagnostic assay capable of specific and sensitive quantification of predominant DNA and RNA viruses of cassava in eastern Africa. The qPCR methods are a great improvement on the existing methods and can be used for monitoring virus spread as well as for accurate evaluation of the cassava varieties for virus resistance. © 2016 The Society for Applied Microbiology.

Microbiological consequences of indoor composting.

Science.gov (United States)

Naegele, A; Reboux, G; Vacheyrou, M; Valot, B; Millon, L; Roussel, S

2016-08-01

Recycling of organic waste appeals to more and more people. The aim of this study was to evaluate the microbiological contamination around organic waste bins at three distances over a 12-month period. Contamination near the customary trash of control households was evaluated at the beginning to ensure that there is no recruitment bias. Air samples using the MAS 100 impactor were carried out in 38 dwellings that do household waste composting and in 10 dwellings of controls. Collection of particles by CIP 10 rotating cup sampler and dust samples collected by electrostatic dust collector cloths were acquired in dwellings that do household waste composting. Samples were analyzed by culture and by real-time quantitative PCR. Information about dwelling characteristics and inhabitant practices was obtained by a standardized questionnaire. The genera most often isolated were Penicillium, Aspergillus, Cladosporium and Streptomyces. Near the organic waste bins, bioaerosol samples showed an increase of Acarus siro (P = 0.001). Sedimented dust analyses highlighted an increase of A. siro, Wallemia sebi, Aspergillus versicolor, and Cladosporium sphaerospermum concentrations after a 12-month survey compared to the beginning. Composting favors microorganism development over time, but does not seem to have an effect on the bioaerosol levels and the surface microbiota beyond 0.5 m from the waste bin. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Physico-chemical and microbiological properties of raw fermented sausages are not influenced by color differences of turkey breast meat.

Science.gov (United States)

Popp, J; Krischek, C; Janisch, S; Wicke, M; Klein, G

2013-05-01

It has been suggested that the color of turkey breast meat influences both physico-chemical and microbiological properties of raw fermented sausages. In this study, raw fermented sausages were produced with turkey breast meat in 3 different colors (pale, normal, or dark), which were obtained from 2 fast-growing-genetic-line toms at 2 slaughterhouses. Prior to the sausage production, the breast muscles were sorted into color groups according to the lightness values determined at 24 h postmortem. This meat was subsequently processed to raw fermented sausages using 1.5 or 2.5% curing salt (CS). The pale meat had higher lightness, electrical conductivity, and drip loss, whereas the dark meat showed a darker color only. The physico-chemical (pH, water activity), visual (lightness, redness), and microbial (total plate count) properties of the sausages were not influenced by the color of the turkey breast meat. The sausage made with 2.5% CS had lower aw and higher ash and hardness values than the sausages produced with 1.5% CS. In conclusion, processing of differently colored turkey meat to raw fermented sausages does not influence the quality characteristics of the products. Based on these findings, there is no reason for the sausage producer to separate turkey breast muscles by color before producing raw fermented sausages.

A new double digestion ligation mediated suppression PCR method for simultaneous bacteria DNA-typing and confirmation of species: an Acinetobacter sp. model.

Directory of Open Access Journals (Sweden)

Karolina Stojowska

Full Text Available We have designed a new ddLMS PCR (double digestion Ligation Mediated Suppression PCR method based on restriction site polymorphism upstream from the specific target sequence for the simultaneous identification and differentiation of bacterial strains. The ddLMS PCR combines a simple PCR used for species or genus identification and the LM PCR strategy for strain differentiation. The bacterial identification is confirmed in the form of the PCR product(s, while the length of the PCR product makes it possible to differentiate between bacterial strains. If there is a single copy of the target sequence within genomic DNA, one specific PCR product is created (simplex ddLMS PCR, whereas for multiple copies of the gene the fingerprinting patterns can be obtained (multiplex ddLMS PCR. The described ddLMS PCR method is designed for rapid and specific strain differentiation in medical and microbiological studies. In comparison to other LM PCR it has substantial advantages: enables specific species' DNA-typing without the need for pure bacterial culture selection, is not sensitive to contamination with other cells or genomic DNA, and gives univocal "band-based" results, which are easy to interpret. The utility of ddLMS PCR was shown for Acinetobacter calcoaceticus-baumannii (Acb complex, the genetically closely related and phenotypically similar species and also important nosocomial pathogens, for which currently, there are no recommended methods for screening, typing and identification. In this article two models are proposed: 3' recA-ddLMS PCR-MaeII/RsaI for Acb complex interspecific typing and 5' rrn-ddLMS PCR-HindIII/ApaI for Acinetobacter baumannii intraspecific typing. ddLMS PCR allows not only for DNA-typing but also for confirmation of species in one reaction. Also, practical guidelines for designing a diagnostic test based on ddLMS PCR for genotyping different species of bacteria are provided.

A new double digestion ligation mediated suppression PCR method for simultaneous bacteria DNA-typing and confirmation of species: an Acinetobacter sp. model.

Science.gov (United States)

Stojowska, Karolina; Krawczyk, Beata

2014-01-01

We have designed a new ddLMS PCR (double digestion Ligation Mediated Suppression PCR) method based on restriction site polymorphism upstream from the specific target sequence for the simultaneous identification and differentiation of bacterial strains. The ddLMS PCR combines a simple PCR used for species or genus identification and the LM PCR strategy for strain differentiation. The bacterial identification is confirmed in the form of the PCR product(s), while the length of the PCR product makes it possible to differentiate between bacterial strains. If there is a single copy of the target sequence within genomic DNA, one specific PCR product is created (simplex ddLMS PCR), whereas for multiple copies of the gene the fingerprinting patterns can be obtained (multiplex ddLMS PCR). The described ddLMS PCR method is designed for rapid and specific strain differentiation in medical and microbiological studies. In comparison to other LM PCR it has substantial advantages: enables specific species' DNA-typing without the need for pure bacterial culture selection, is not sensitive to contamination with other cells or genomic DNA, and gives univocal "band-based" results, which are easy to interpret. The utility of ddLMS PCR was shown for Acinetobacter calcoaceticus-baumannii (Acb) complex, the genetically closely related and phenotypically similar species and also important nosocomial pathogens, for which currently, there are no recommended methods for screening, typing and identification. In this article two models are proposed: 3' recA-ddLMS PCR-MaeII/RsaI for Acb complex interspecific typing and 5' rrn-ddLMS PCR-HindIII/ApaI for Acinetobacter baumannii intraspecific typing. ddLMS PCR allows not only for DNA-typing but also for confirmation of species in one reaction. Also, practical guidelines for designing a diagnostic test based on ddLMS PCR for genotyping different species of bacteria are provided.

Real-time PCR-based detection of Bordetella pertussis and Bordetella parapertussis in an Irish paediatric population.

LENUS (Irish Health Repository)

Grogan, Juanita A

2011-06-01

Novel real-time PCR assays targeting the Bordetella pertussis insertion sequence IS481, the toxin promoter region and Bordetella parapertussis insertion sequence IS1001 were designed. PCR assays were capable of detecting ≤10 copies of target DNA per reaction, with an amplification efficiency of ≥90 %. From September 2003 to December 2009, per-nasal swabs and nasopharyngeal aspirates submitted for B. pertussis culture from patients ≤1 month to >15 years of age were examined by real-time PCR. Among 1324 patients, 76 (5.7 %) were B. pertussis culture positive and 145 (10.95 %) were B. pertussis PCR positive. Of the B. pertussis PCR-positive patients, 117 (81 %) were aged 6 months or less. A total of 1548 samples were examined, of which 87 (5.6 %) were culture positive for B. pertussis and 169 (10.92 %) were B. pertussis PCR positive. All culture-positive samples were PCR positive. Seven specimens (0.5 %) were B. parapertussis culture positive and 10 (0.8 %) were B. parapertussis PCR positive, with all culture-positive samples yielding PCR-positive results. A review of patient laboratory records showed that of the 1324 patients tested for pertussis 555 (42 %) had samples referred for respiratory syncytial virus (RSV) testing and 165 (30 %) were positive, as compared to 19.4 % of the total 5719 patients tested for RSV in this period. Analysis of the age distribution of RSV-positive patients identified that 129 (78 %) were aged 6 months or less, similar to the incidence observed for pertussis in that patient age group. In conclusion, the introduction of the real-time PCR assays for the routine detection of B. pertussis resulted in a 91 % increase in the detection of the organism as compared to microbiological culture. The incidence of infection with B. parapertussis is low while the incidence of RSV infection in infants suspected of having pertussis is high, with a similar age distribution to B. pertussis infection.

Soil microbiology

International Nuclear Information System (INIS)

Wolf, D.C.; Legg, J.O.

1984-01-01

The major areas of soil microbiological and biochemical research which have involved both stable and radioactive isotopes are summarized. These include microbial decomposition of naturally occurring materials, microbial biomass, interactions of plants and microbes, denitrification, mineralization and immobilization of nitrogen and biological nitrogen fixation. (U.K.)

Undergraduate Laboratory Exercises Specific to Food Spoilage Microbiology

Science.gov (United States)

Snyder, Abigail B.; Worobo, Randy W.; Orta-Ramirez, Alicia

2016-01-01

Food spoilage has an enormous economic impact, and microbial food spoilage plays a significant role in food waste and loss; subsequently, an equally significant portion of undergraduate food microbiology instruction should be dedicated to spoilage microbiology. Here, we describe a set of undergraduate microbiology laboratory exercises that focus…

Diagnostic microbiology in veterinary dermatology: present and future

DEFF Research Database (Denmark)

Guardabassi, Luca; Damborg, Peter; Stamm, Ivonne

2017-01-01

the identification (ID) and antimicrobial susceptibility testing (AST) of key pathogens in veterinary dermatology. Methods The Study Group for Veterinary Microbiology (ESGVM) of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) identified scientific, technological, educational...... not adequately equipped to run up-to-date clinical microbiologic diagnostic tests. Conclusions and clinical importance ESGVM recommends the use of laboratories employing mass spectrometry for ID and broth micro-dilution for AST, and offering assistance by expert microbiologists on pre- and post-analytical issues......Background The microbiology laboratory can be perceived as a service provider rather than an integral part of the healthcare team. Objectives The aim of this review is to discuss the current challenges of providing a state-of-the-art diagnostic veterinary microbiology service including...

Microbiological Quality of Fresh Nopal Juice

Directory of Open Access Journals (Sweden)

Ana María Hernández-Anguiano

2016-12-01

Full Text Available The consumption of fresh nopal cactus juice is widely popular among health-conscious consumers in Mexico. The juice is prepared from fresh cladodes that have only been rinsed with tap water and are not subjected to a pasteurization or terminal bacterial reduction process. The aim of this study was to evaluate the microbial quality of commercially available fresh juices (n = 162 made with nopal in Texcoco, State of Mexico, during the summer and spring season. Standard microbiological methods, the PCR technique and the serological method were used for isolation and identification of bacteria. All samples contained total coliforms and 91% were positive for Escherichia coli. Although total coliforms and E. coli were detected throughout the study, their populations were significantly lower (p < 0.05 in winter and spring, respectively. Citrobacter youngae was found in 20% of the samples, an unidentified species of Citrobacter in 10%, C. freundii and Proteus mirabilis in 3%, and Salmonella Javiana in 1%. The presence of these microorganisms, especially Salmonella, in the nopal juices is unacceptable due to its health significance. The information generated in this study is relevant for human health risk assessment associated with the consumption of unpasteurized nopal juices and potential interventions to minimize pathogen contamination.

Journal of Tropical Microbiology and Biotechnology

African Journals Online (AJOL)

The Journal of Tropical Microbiology and Biotechnology (JTMB) formerly Journal of Tropical Microbiology gives preeminence to the central role of modern biotechnology and microorganisms as tools and targets in current research, which is largely multidisciplinary. JTMB covers a broad range of topics, such as disease ...

Teaching microbiological food safety through case studies

Directory of Open Access Journals (Sweden)

Florence Dubois-Brissonnet

2015-10-01

Full Text Available Higher education students usually ask for more training based on case studies. This was addressed by designing a specific food safety module (24 hours in which students were shown how to predict microbiological risks in food products i.e. they were asked to determine product shelf-life according to product formulation, preservation methods and consumption habits using predictive microbiology tools. Working groups of four students first identified the main microbiological hazards associated with a specific product. To perform this task, they were given several documents including guides for good hygiene practices, reviews on microbiological hazards in the food sector, flow sheets, etc…  After three-hours of work, the working groups prepared and gave an oral presentation in front of their classmates and professors. This raised comments and discussion that allowed students to adjust their conclusions before beginning the next step of their work. This second step consisted in the evaluation of the safety risk associated with the two major microbiological hazards of the product studied, using predictive microbiology. Students then attended a general lecture on the different tools of predictive microbiology and tutorials (6 hours that made them familiar with the modelling of bacterial growth or inactivation. They applied these tools (9 hours to predict the shelf-life of the studied product according to various scenarios of preservation (refrigeration, water activity, concentration of salt or acid, modified atmosphere, etc… and/or consumption procedures (cooking. The module was concluded by oral presentations of each working group and included student evaluation (3 hours.

PCR

African Journals Online (AJOL)

Elham

2013-07-03

Jul 3, 2013 ... was constructed with competitive strategy by PCR-cloning technique and the limitation range was determined. The PCR products of MTB and IAC were 245 and 660 bp, respectively on .... products' differentiation was easy.

Molecular diagnosis of bloodstream infections in onco-haematology patients with PCR/ESI-MS technology.

Science.gov (United States)

Jordana-Lluch, Elena; Rivaya, Belén; Marcó, Clara; Giménez, Montserrat; Quesada, Mª Dolores; Escobedo, Agustín; Batlle, Montserrat; Martró, Elisa; Ausina, Vicente

2017-02-01

Onco-haematological patients are prone to develop infections, and antibiotic prophylaxis may lead to negative blood cultures. Thus, the microbiological diagnosis and subsequent administration of a targeted antimicrobial therapy is often difficult. The goal of this study was to evaluate the usefulness of IRIDICA (PCR/ESI-MS technology) for the molecular diagnosis of bloodstream infections in this patient group. A total of 463 whole blood specimens from different sepsis episodes in 429 patients were analysed using the PCR/ESI-MS platform, comparing the results with those of blood culture and other clinically relevant information. The sensitivity of PCR/ESI-MS by specimen (excluding polymicrobial infections, n = 25) in comparison with blood culture was 64.3% overall, 69.0% in oncological patients, and 59.3% in haematological patients. When comparing with a clinical infection criterion, overall sensitivity rose to 74.7%, being higher in oncological patients (80.0%) than in haematological patients (67.7%). Thirty-one microorganisms isolated by culture were not detected by IRIDICA, whereas 42 clinically relevant pathogens not isolated by culture were detected moleculary. PCR/ESI-MS offers a reliable identification of pathogens directly from whole blood. While additional studies are needed to confirm our findings, the system showed a lower sensitivity in onco-haematological patients in comparison with previously reported results in patients from the Intensive Care Unit. Copyright © 2016 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

New Egyptian Journal of Microbiology: Journal Sponsorship

African Journals Online (AJOL)

New Egyptian Journal of Microbiology: Journal Sponsorship. Journal Home > About the Journal > New Egyptian Journal of Microbiology: Journal Sponsorship. Log in or Register to get access to full text downloads.

Designing of primers for detection of salmonella typhimirium and enteritidis by heminested PCR

International Nuclear Information System (INIS)

Ben salem, Issam

2007-01-01

Salmonella are the main responsible agent for the frequent food borne gastrointestinal diseases. In Tunisia, this pathogen is considered one of the most important causes of toxiinfections and its detection using classical methods is laborious and requires a large amount of time for revelation. To solve this problem, we developed a rapid molecular technique for the detection of the invA virulence gene sequence which is found in the majority of Salmonella spp. This technique is a hemi nested PCR amplification using specific primers designed and by bioinformatics tools. The detection method consisted of pre-enrichment of the sample in buffered peptone water (BPW), followed by a total DNA extraction step prior to single tube hemi nested PCR amplification. This method was found highly specific and sensitive to detect low levels of salmonella typhimurium and salmonella enteritidis (1cfu/ 25g) in naturally contaminated spicy sausage (merguez) samples. These results can benefit the public health agencies concerning microbiological and quality aspects of the commercial and traditional merguez meat production in Tunisia. (Author)

Evaluation of multiplex tandem real-time PCR for detection of Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis in clinical stool samples.

Science.gov (United States)

Stark, D; Al-Qassab, S E; Barratt, J L N; Stanley, K; Roberts, T; Marriott, D; Harkness, J; Ellis, J T

2011-01-01

The aim of this study was to describe the first development and evaluation of a multiplex tandem PCR (MT-PCR) assay for the detection and identification of 4 common pathogenic protozoan parasites, Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis, from human clinical samples. A total of 472 fecal samples submitted to the Department of Microbiology at St. Vincent's Hospital were included in the study. The MT-PCR assay was compared to four real-time PCR (RT-PCR) assays and microscopy by a traditional modified iron hematoxylin stain. The MT-PCR detected 28 G. intestinalis, 26 D. fragilis, 11 E. histolytica, and 9 Cryptosporidium sp. isolates. Detection and identification of the fecal protozoa by MT-PCR demonstrated 100% correlation with the RT-PCR results, and compared to RT-PCR, MT-PCR exhibited 100% sensitivity and specificity, while traditional microscopy of stained fixed fecal smears exhibited sensitivities and specificities of 56% and 100% for Cryptosporidium spp., 38% and 99% for D. fragilis, 47% and 97% for E. histolytica, and 50% and 100% for G. intestinalis. No cross-reactivity was detected in 100 stool samples containing various other bacterial, viral, and protozoan species. The MT-PCR assay was able to provide rapid, sensitive, and specific simultaneous detection and identification of the four most important diarrhea-causing protozoan parasites that infect humans. This study also highlights the lack of sensitivity demonstrated by microscopy, and thus, molecular methods such as MT-PCR must be considered the diagnostic methods of choice for enteric protozoan parasites.

The Diagnostic Utility of Bact/ALERT and Nested PCR in the Diagnosis of Tuberculous Meningitis.

Science.gov (United States)

Sastry, Apurba Sankar; Bhat K, Sandhya; Kumudavathi

2013-01-01

The early laboratory diagnosis of Tuberculous Meningitis (TBM) is crucial, to start the antitubercular chemotherapy and to prevent its complications. However, the conventional methods are either less sensitive or time consuming. Hence, the diagnostic potentials of BacT/ALERT and Polymerase Chain Reaction (PCR) was evaluated in this study. The study group comprised of 62 cases and 33 controls. The cases were divided according to Ahuja's criteria into the confirmed (two cases), highly probable (19 cases), probable (26 cases) and the possible (15 cases) subgroups. Ziehl Neelsen's (ZN) and Auramine Phenol (AP) staining, Lowenstein Jensen (LJ) medium culture, BacT/ALERT and nested Polymerase Chain Reaction (PCR) which targeted IS6110 were carried out on all the patients. The sensitivity of the LJ culture was 3.22%. BacT/ALERT showed a sensitivity and a specificity of 25.80% and 100% and those of nested PCR were found to be 40.32% and 96.97% respectively. The mean detection time of growth of the LJ culture was 31.28 days, whereas that of BacT/ALERT was 20.68 days. The contamination rate in the LJ culture and BacT/ALERT were 7.2% and 5.8% respectively. Nested PCR was found to be more sensitive, followed by BacT/ALERT as compared to the LJ culture and smear microscopy. As both false negative and false positive results have been reported for nested PCR, so it should not be used alone as a criterion for initiating or terminating the therapy, but it should be supported by clinical, radiological, cytological and other microbiological findings.

Quantification of bacterial and archaeal symbionts in high and low microbial abundance sponges using real-time PCR

KAUST Repository

Bayer, Kristina

2014-07-09

In spite of considerable insights into the microbial diversity of marine sponges, quantitative information on microbial abundances and community composition remains scarce. Here, we established qPCR assays for the specific quantification of four bacterial phyla of representative sponge symbionts as well as the kingdoms Eubacteria and Archaea. We could show that the 16S rRNA gene numbers of Archaea, Chloroflexi, and the candidate phylum Poribacteria were 4-6 orders of magnitude higher in high microbial abundance (HMA) than in low microbial abundance (LMA) sponges and that actinobacterial 16S rRNA gene numbers were 1-2 orders higher in HMA over LMA sponges, while those for Cyanobacteria were stable between HMA and LMA sponges. Fluorescence in situ hybridization of Aplysina aerophoba tissue sections confirmed the numerical dominance of Chloroflexi, which was followed by Poribacteria. Archaeal and actinobacterial cells were detected in much lower numbers. By use of fluorescence-activated cell sorting as a primer- and probe-independent approach, the dominance of Chloroflexi, Proteobacteria, and Poribacteria in A. aerophoba was confirmed. Our study provides new quantitative insights into the microbiology of sponges and contributes to a better understanding of the HMA/LMA dichotomy. The authors quantified sponge symbionts in eight sponge species from three different locations by real time PCR targetting 16S rRNA genes. Additionally, FISH was performed and diversity and abundance of singularized microbial symbionts from Aplysina aerophoba was determined for a comprehensive quantification work. © 2014 Federation of European Microbiological Societies.

Evaluation of efficiency of nested multiplex allele-specific PCR assay for detection of multidrug resistant tuberculosis directly from sputum samples.

Science.gov (United States)

Mistri, S K; Sultana, M; Kamal, S M M; Alam, M M; Irin, F; Nessa, J; Ahsan, C R; Yasmin, M

2016-05-01

For an effective control of tuberculosis, rapid detection of multidrug resistant tuberculosis (MDR-TB) is necessary. Therefore, we developed a modified nested multiplex allele-specific polymerase chain reaction (MAS-PCR) method that enables rapid MDR-TB detection directly from sputum samples. The efficacy of this method was evaluated using 79 sputum samples collected from suspected tuberculosis patients. The performance of nested MAS-PCR method was compared with other MDR-TB detection methods like drug susceptibility testing (DST) and DNA sequencing. As rifampicin (RIF) resistance conforms to MDR-TB in greater than 90% cases, only the presence of RIF-associated mutations in rpoB gene was determined by DNA sequencing and nested MAS-PCR to detect MDR-TB. The concordance between nested MAS-PCR and DNA sequencing results was found to be 96·3%. When compared with DST, the sensitivity and specificity of nested MAS-PCR for RIF-resistance detection were determined to be 92·9 and 100% respectively. For developing- and high-TB burden countries, molecular-based tests have been recommended by the World Health Organization for rapid detection of MDR-TB. The results of this study indicate that, nested MAS-PCR assay might be a practical and relatively cost effective molecular method for rapid detection of MDR-TB from suspected sputum samples in developing countries with resource poor settings. © 2016 The Society for Applied Microbiology.

High pressure and thermal pasteurization effects on sweet cherry juice microbiological stability and physicochemical properties

Science.gov (United States)

Queirós, Rui P.; Rainho, Daniel; Santos, Mauro D.; Fidalgo, Liliana G.; Delgadillo, Ivonne; Saraiva, Jorge A.

2015-01-01

This study evaluated high pressure processing (P1 - 400 MPa/5 min; P2 - 550 MPa/2 min) and thermal pasteurization (TP - 70°C/30 s) effects on sweet cherry juice's microbiological and physicochemical parameters, during four weeks of refrigerated storage. All treatments reduced the microbiological load to undetectable levels not affecting total soluble solids and titratable acidity. The pH increased with all treatments, however, it decreased during storage. Phenols were differently affected: TP increased them by 6%, P1 had no effect while P2 decreased them by 11%. During storage, phenols in control and TP samples decreased by 26% and 20%, P1 samples decreased them by 11% whereas P2 showed no variation. TP had no effect on anthocyanins, while pressure treatments increased them by 8%. Anthocyanins decreased during storage, particularly in the control and P1 (decreasing 41%). All treatments had no effect on antioxidant activity until the 14th day, thereafter high pressure processing samples showed the highest antioxidant activity.

Matrix approach to the simultaneous detection of multiple potato pathogens by real-time PCR.

Science.gov (United States)

Nikitin, M M; Statsyuk, N V; Frantsuzov, P A; Dzhavakhiya, V G; Golikov, A G

2018-03-01

Create a method for highly sensitive, selective, rapid and easy-to-use detection and identification of economically significant potato pathogens, including viruses, bacteria and oomycetes, be it single pathogen, or a range of various pathogens occurring simultaneously. Test-systems for real-time PCR, operating in the unified amplification regime, have been developed for Phytophthora infestans, Pectobacterium atrosepticum, Dickeya dianthicola, Dickeya solani, Ralstonia solanacearum, Pectobacterium carotovorum, Clavibacter michiganensis subsp. sepedonicus, potato viruses Y (ordinary and necrotic forms as well as indiscriminative test system, detecting all forms), A, X, S, M, potato leaf roll virus, potato mop top virus and potato spindle tuber viroid. The test-systems (including polymerase and revertase) were immobilized and lyophilized in miniature microreactors (1·2 μl) on silicon DNA/RNA microarrays (micromatrices) to be used with a mobile AriaDNA ® amplifier. Preloaded 30-reaction micromatrices having shelf life of 3 and 6 months (for RNA- and DNA-based pathogens, respectively) at room temperature with no special conditions were successfully tested on both reference and field samples in comparison with traditional ELISA and microbiological methods, showing perfect performance and sensitivity (1 pg). The accurate, rapid and user-friendly diagnostic system in a micromatrix format may significantly contribute to pathogen screening and phytopathological studies. © 2018 The Authors. Journal of Applied Microbiology published by John Wiley & Sons Ltd on behalf of The Society for Applied Microbiology.

[Bacterial identification methods in the microbiology laboratory].

Science.gov (United States)

Bou, Germán; Fernández-Olmos, Ana; García, Celia; Sáez-Nieto, Juan Antonio; Valdezate, Sylvia

2011-10-01

In order to identify the agent responsible of the infectious process and understanding the pathogenic/pathological implications, clinical course, and to implement an effective antimicrobial therapy, a mainstay in the practice of clinical microbiology is the allocation of species to a microbial isolation. In daily routine practice microbiology laboratory phenotypic techniques are applied to achieve this goal. However, they have some limitations that are seen more clearly for some kinds of microorganism. Molecular methods can circumvent some of these limitations, although its implementation is not universal. This is due to higher costs and the level of expertise required for thei implementation, so molecular methods are often centralized in reference laboratories and centers. Recently, proteomics-based methods made an important breakthrough in the field of diagnostic microbiology and will undoubtedly have a major impact on the future organization of the microbiology services. This paper is a short review of the most noteworthy aspects of the three bacterial identification methods described above used in microbiology laboratories. Copyright © 2011 Elsevier España, S.L. All rights reserved.

Automation in the clinical microbiology laboratory.

Science.gov (United States)

Novak, Susan M; Marlowe, Elizabeth M

2013-09-01

Imagine a clinical microbiology laboratory where a patient's specimens are placed on a conveyor belt and sent on an automation line for processing and plating. Technologists need only log onto a computer to visualize the images of a culture and send to a mass spectrometer for identification. Once a pathogen is identified, the system knows to send the colony for susceptibility testing. This is the future of the clinical microbiology laboratory. This article outlines the operational and staffing challenges facing clinical microbiology laboratories and the evolution of automation that is shaping the way laboratory medicine will be practiced in the future. Copyright © 2013 Elsevier Inc. All rights reserved.

Neutralization Assay for Zika and Dengue Viruses by Use of Real-Time-PCR-Based Endpoint Assessment.

Science.gov (United States)

Wilson, Heather L; Tran, Thomas; Druce, Julian; Dupont-Rouzeyrol, Myrielle; Catton, Michael

2017-10-01

The global spread and infective complications of Zika virus (ZKV) and dengue virus (DENV) have made them flaviviruses of public health concern. Serological diagnosis can be challenging due to antibody cross-reactivity, particularly in secondary flavivirus infections or when there is a history of flavivirus vaccination. The virus neutralization assay is considered to be the most specific assay for measurement of anti-flavivirus antibodies. This study describes an assay where the neutralization endpoint is measured by real-time PCR, providing results within 72 h. It demonstrated 100% sensitivity (24/24 ZKV and 15/15 DENV) and 100% specificity (11/11 specimens) when testing well-characterized sera. In addition, the assay was able to determine the correct DENV serotype in 91.7% of cases. The high sensitivity and specificity of the real-time PCR neutralization assay makes it suitable to use as a confirmatory test for sera that are reactive in commercial IgM/IgG enzyme immunoassays. Results are objective and the PCR-based measurement of the neutralization endpoint lends itself to automation so that throughput may be increased in times of high demand. Copyright © 2017 American Society for Microbiology.

Women with symptoms of a urinary tract infection but a negative urine culture: PCR-based quantification of Escherichia coli suggests infection in most cases.

Science.gov (United States)

Heytens, S; De Sutter, A; Coorevits, L; Cools, P; Boelens, J; Van Simaey, L; Christiaens, T; Vaneechoutte, M; Claeys, G

2017-09-01

Our objective was to examine whether or not women with symptoms of a urinary tract infection but with a negative culture (20%-30%) do have an infection. We performed quantitative PCR (qPCR) for Escherichia coli and Staphylococcus saprophyticus, on top of a standard culture, in urine samples from 220 women with dysuria and/or frequency and/or urgency and from 86 women without symptoms. For symptomatic women, qPCR was also carried out for four sexually transmitted agents. In the symptomatic group, 80.9% (178/220) of the urine cultures were positive for any uropathogen and 95.9% (211/220) were E. coli qPCR-positive. For the control group, cultures for E. coli and E. coli qPCR were positive in, respectively, 10.5% (9/86) and 11.6% (10/86). In the symptomatic group, qPCR yielded 19 positive samples for S. saprophyticus qPCR, one positive sample for Mycoplasma genitalium and one for Trichomonas vaginalis. These findings suggest that almost all women with typical urinary complaints and a negative culture still have an infection with E. coli. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Effects of sous-vide method at different temperatures, times and vacuum degrees on the quality, structural, and microbiological properties of pork ham.

Science.gov (United States)

Jeong, Kiyoung; O, Hyeonbin; Shin, So Yeon; Kim, Young-Soon

2018-04-10

This study evaluated the influence of different factors on pork hams cooked by sous-vide method. The quality and structural and microbiological properties of the treated samples were compared with those of controls. Samples were subjected to treatment at different combinations of temperature (61 °C or 71 °C), time (45 or 90 min), and vacuum degree (98.81% or 96.58%). The control sample was air packaged and boiled for 45 min in boiling water. Temperature and vacuum degree affected quality properties, while the effect of time was limited. Samples cooked at 61 °C showed higher moisture content, redness, and pink color of the meat juice, whereas samples cooked at 71 °C showed higher cooking loss rate, lightness, and volatile basic nitrogen values. Texture analysis indicated tenderer meat for the treatment group than the control. No microbial growth was detected in any treatment groups. Meat cooked at 61 °C and 98.81% vacuum showed more spacious arrangement of meat fiber. Copyright © 2018 Elsevier Ltd. All rights reserved.

Recent advances in diagnostic microbiology.

Science.gov (United States)

Bravo, Lulette Tricia C; Procop, Gary W

2009-07-01

The past decade has seen a surge in the development of a variety of molecular diagnostics designed to rapidly identify or characterize medically important microorganisms. We briefly review important advances in molecular microbiology, and then discuss specific assays that have been implemented in clinical microbiology laboratories throughout the country. We also discuss emerging methods and technologies that will soon be more widely used for the prompt and accurate detection of the agents of infectious diseases.

Prospective evaluation of the SeptiFAST multiplex real-time PCR assay for surveillance and diagnosis of infections in haematological patients after allogeneic stem cell transplantation compared to routine microbiological assays and an in-house real-time PCR method.

Science.gov (United States)

Elges, Sandra; Arnold, Renate; Liesenfeld, Oliver; Kofla, Grzegorz; Mikolajewska, Agata; Schwartz, Stefan; Uharek, Lutz; Ruhnke, Markus

2017-12-01

We prospectively evaluated a multiplex real-time PCR assay (SeptiFast, SF) in a cohort of patients undergoing allo-BMT in comparison to an in-house PCR method (IH-PCR). Overall 847 blood samples (mean 8 samples/patient) from 104 patients with haematological malignancies were analysed. The majority of patients had acute leukaemia (62%) with a mean age of 52 years (54% female). Pathogens could be detected in 91 of 847 (11%) samples by SF compared to 38 of 205 (18.5%) samples by BC, and 57 of 847 (6.7%) samples by IH-PCR. Coagulase-negative staphylococci (n=41 in SF, n=29 in BC) were the most frequently detected bacteria followed by Escherichia coli (n=9 in SF, n=6 in BC). Candida albicans (n=17 in SF, n=0 in BC, n=24 in IH-PCR) was the most frequently detected fungal pathogen. SF gave positive results in 5% of samples during surveillance vs in 26% of samples during fever episodes. Overall, the majority of blood samples gave negative results in both PCR methods resulting in 93% overall agreement resulting in a negative predictive value of 0.96 (95% CI: 0.95-0.97), and a positive predictive value of 0.10 (95% CI: -0.01 to 0.21). SeptiFast appeared to be superior over BC and the IH-PCR method. © 2017 Blackwell Verlag GmbH.

Reducing Unnecessary and Duplicate Ordering for Ovum and Parasite Examinations and Clostridium difficile PCR in Immunocompromised Patients by Using an Alert at the Time of Request in the Order Management System.

Science.gov (United States)

Otto, Caitlin C; Shuptar, Susan L; Milord, Philippe; Essick, Connor J; Nevrekar, Reshma; Granovsky, Svetlana L; Seo, Susan K; Babady, N Esther; Martin, Steven C; Tang, Yi-Wei; Pessin, Melissa S

2015-08-01

We implemented hospital information system (HIS) alerts to deter unnecessary test orders for ovum and parasite (O&P) exams and Clostridium difficile PCR. The HIS alerts decreased noncompliant O&P orders (orders after >72 h of hospitalization) from 49.8% to 30.9%, an overall decrease of 19%, and reduced noncompliant C. difficile PCR orders (orders <7 days after a previous positive result) from 30.6% to 19.2%, an overall decrease of 31.9%. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Detection of Salmonella Spp., Shigella (Flexneri and Sonnei) and Vibrio Cholerae O1 by Polymerase Chain Reaction (PCR) in Exported Shrimp from the Mexican Northeast Coast

Energy Technology Data Exchange (ETDEWEB)

Perez, L.; Nuñez, F.; Rubio, M.; Nicoli, M. [Universidad Nacional Autónoma de México, Facultad de Medicina Veterinaria y Zootecnia (Mexico)

2005-01-15

The objective of the present work was to use the PCR technique for the simultaneous detection of Salmonella spp and Vibrio cholerae O1 in frozen shrimp for export. The DNA segments located in the gene A [284 pairs of bases (pb)] from Salmonella spp. locus ial (217 and 320 pb) from Shigella flexneri and Shigella sonnei and the gene ctxA and ctxB (777 pb) from Vibrio cholerae O1 were amplified. The different primers that amplify these segments were assayed in a PCR reaction for the simultaneous detection of DNA from the microorganisms. It was not possible to amplify the gene of Shigella sonnei and Shigella flexneri under the assay’s conditions, whilst those of Salmonella spp. and Vibrio cholerae O1 were successfully amplified. The amplification conditions for the PCR were: 94° C, 58° C and 72° C during 30 cycles, allowing a reduction from 15 days test time with the official microbiological methods to 28 hours (24 for the pre-enrichment and four for the PCR). Samples of raw-frozen-headless shrimps were taken from production plants located in the State of Sinaloa, Mexico. A random sampling procedure was used, according to the guidelines described by the International Commission of Microbiological Specifications for Foods (ICMSF, 1999). Five packages per lot per production plant were obtained. From each individual package (5 pounds 80 OZ ≈ 2.27 kg) three samples were taken for the bacteriological assays to search for Salmonella spp. and Vibrio cholerae O1, respectively. The samples were also analyzed by PCR. Results showed that none of the samples were positive by PCR to any of the studied bacteria. Salmonella spp. and Vibrio cholerae O1 were not detected in these samples by the official methods. However, the latter were able to identify other Vibrio species and enterobacteria like Proteus and Acromobacter. These results confirmed PCR’s rapidity, sensitivity and specificity. (author)

Absolute quantification by droplet digital PCR versus analog real-time PCR

Science.gov (United States)

Hindson, Christopher M; Chevillet, John R; Briggs, Hilary A; Gallichotte, Emily N; Ruf, Ingrid K; Hindson, Benjamin J; Vessella, Robert L; Tewari, Muneesh

2014-01-01

Nanoliter-sized droplet technology paired with digital PCR (ddPCR) holds promise for highly precise, absolute nucleic acid quantification. Our comparison of microRNA quantification by ddPCR and real-time PCR revealed greater precision (coefficients of variation decreased by 37–86%) and improved day-to-day reproducibility (by a factor of seven) of ddPCR but with comparable sensitivity. When we applied ddPCR to serum microRNA biomarker analysis, this translated to superior diagnostic performance for identifying individuals with cancer. PMID:23995387

Shelf-life Extension and Improvement of the Microbiological Quality of Fresh Sausage by Irradiation

International Nuclear Information System (INIS)

Hammad, A.A.I.; El-Mongy, T.M.; Mabrouk, A.K.

2000-01-01

Fifty samples of fresh sausage were randomly collected from different meat products markets in Great Cairo. They were analysed for microbiological quality. The results showed that 26 (52%) samples had total aerobic bacterial counts more than 10 7 cfu/g. Staphylococcus aureus was present in all samples and 19 (38%) samples had counts more than maximum permissible level (10 3 cfu/g). Enterococcus faecalis numbers more than 10 5 cfu/g were found in 14 (28%) samples. Coliform bacteria were present in all sausage samples and 19(38%) samples had counts more than 10 3 cfu/g, while salmonella was detected in only 5 (10%) samples. Therefore, fresh sausages in local market were highly contaminated with different microorganisms including spoilage and pathogenic bacteria. Irradiation dose of 4 kGy greatly reduced the numbers of aerobic and anaerobic bacteria, lactobacilli and yeasts without affecting the organoleptic properties of the samples. It extended the shelf-life of fresh sausage up to about 15 days at refrigeration temperature (5+-1) while the shelf-life was only 5 days for unirradiated samples. Irradiation dose of 6 kGy had greater effect on the microbiological counts and extended the shelf-life of fresh sausage more than 25 days, however, it slightly affected its organoleptic properties. Sausage samples exposed to this irradiation dose was microbiologically safe, being free from Enterobacteriaceae, Staph, aureus, Ent, faecalis, coliform bacteria, Salmonella and moulds

Predictive Food Microbiology

DEFF Research Database (Denmark)

Østergaard, Nina Bjerre

Listeria monocytogenes is a well-known food borne pathogen that potentially causes listeriosis. No outbreaks or cases of listeriosis have been associated with cottage cheese, but several confirmed cases and outbreaks in the EU and the US have been related to dairy products made from raw...... or pasteurised milk. This, in combination with the fact that cottage cheese support growth of Listeria monocytogenes, induces a documentation requirement on the food producer. In the EU regulatory framework, mathematical models are recognised as a suitable supplement to traditional microbiological methods....... The models can be used for documentation of compliance with microbiological criteria for Listeria monocytogenes under reasonably foreseeable conditions. Cottage cheese is a fresh, fermented dairy product. It consists of a fermented cheese curd mixed with a fresh or cultured cream dressing. The product...

Screening for methicillin-resistant Staphylococcus aureus in clinical swabs using a high-throughput real-time PCR-based method

DEFF Research Database (Denmark)

Ornskov, D; Kolmos, B; Bendix Horn, P

2008-01-01

2005, all patients and healthcare personnel have been screened for MRSA colonisation, involving analysis of 300-400 samples daily. To deal with this number of samples, a PCR-based method customised for high-throughput analysis and a system for fast reporting of MRSA carrier status were developed. Swab...... samples were incubated overnight in a selective tryptone soya broth and were analysed by PCR the following day. Using this strategy, non-colonised individuals were identified within 24 h, while MRSA-positive samples were analysed further by traditional microbiological methods to determine the resistance...... pattern. This is a cost-effective approach, as the greatest expense in hospitals involves the isolation of patients of unknown MRSA status. The method was evaluated by testing 2194 clinical samples, with a sensitivity and specificity of 100% and 94%, respectively. The analytical sensitivity was 97...

Polyphenolic content, antiradical activity, stability and microbiological quality of elderberry (Sambucus nigra L.) extracts.

Science.gov (United States)

Pliszka, Barbara

2017-01-01

The pharmaceutical and food industries expect detailed knowledge on the physicochemical properties of elderberry fruit extracts, their stability and microbiological quality, as well as the polyphenol content in elderberry cultivars. The characteristics of the extracts might be additionally modified by citric acid, which improves the stability of anthocyanins and protects processed fruits and syrups from pathogenic microorganisms. The choice of the method with citric acid was a consequence of the physicochemical charac teristics of elderberry pigments, which are not stable under the effect of light in alcoholic solutions. The aim of study was to analyze the properties of elderberry fruit extracts regarding polyphenol content and antiradical activity, as well as their stability and microbiological quality. The plant material consisted of fruit from four cultivars (Alleso, Korsor, Sampo, Samyl) of black elderberry (Sambucus nigra L.). The following were determined in fruit extracts: polyphe- nolic content (HPLC), antiradical activity (ABTS and DPPH) and stability and microbiological quality. The HPLC analysis of polyphenols demonstrated that the extracts from fruits collected from cv. Samyl had the highest 3-sambubioside cyanidin content and those from cv. Korsor contained the highest quantity of 3-glucoside cyanidin. The extracts from cv. Sampo fruit had a dominant 3-sambubioside-5-gluco- side cyanidin and 3,5-diglucoside cyanidin content. The highest quercetin (5.92 mg 100 mg-1 of extract) and caffeic acid (1.21 mg 100 mg-1 of extract) content was found in fruit extracts from cv. Alleso. The cultivars Samyl and Korsor had a higher level of anthocyanins and higher antiradical activity (ABTS) in fruit extracts than cv. Alleso and Sampo. The antiradical activity (DPPH) of fruit extracts from elderberry cultivars as- sessed in this research was similar. The degradation index for all fruit extracts was similar (DI = 1.035). The microbiological species detected in

Performance of a Highly Sensitive Mycobacterium tuberculosis Complex Real-Time PCR Assay for Diagnosis of Pulmonary Tuberculosis in a Low-Prevalence Setting: a Prospective Intervention Study.

Science.gov (United States)

Vinuesa, Víctor; Borrás, Rafael; Briones, María Luisa; Clari, María Ángeles; Cresencio, Vicenta; Giménez, Estela; Muñoz, Carmen; Oltra, Rosa; Servera, Emilio; Scheelje, Talia; Tornero, Carlos; Navarro, David

2018-05-01

The potential impact of routine real-time PCR testing of respiratory specimens from patients with presumptive tuberculosis in terms of diagnostic accuracy and time to tuberculosis treatment inception in low-prevalence settings remains largely unexplored. We conducted a prospective intervention cohort study. Respiratory specimens from 1,020 patients were examined by acid-fast bacillus smear microscopy, tested by a real-time Mycobacterium tuberculosis complex PCR assay (Abbott RealTi me MTB PCR), and cultured in mycobacterial media. Seventeen patients tested positive by PCR (5 were acid-fast bacillus smear positive and 12 acid-fast bacillus smear negative), and Mycobacterium tuberculosis was recovered from cultures for 12 of them. Patients testing positive by PCR and negative by culture ( n = 5) were treated and deemed to have responded to antituberculosis therapy. There were no PCR-negative/culture-positive cases, and none of the patients testing positive for nontuberculous mycobacteria ( n = 20) yielded a positive PCR result. The data indicated that routine testing of respiratory specimens from patients with presumptive tuberculosis by the RealTi me MTB PCR assay improves the tuberculosis diagnostic yield and may reduce the time to antituberculosis treatment initiation. On the basis of our data, we propose a novel mycobacterial laboratory algorithm for tuberculosis diagnosis. Copyright © 2018 American Society for Microbiology.

76 FR 67461 - Cosmetic Microbiological Safety Issues; Public Meeting

Science.gov (United States)

2011-11-01

...] Cosmetic Microbiological Safety Issues; Public Meeting AGENCY: Food and Drug Administration, HHS. ACTION... Administration (FDA) is announcing a public meeting entitled ``Cosmetic Microbiological Safety Issues.'' The... cosmetic microbiological safety and to suggest areas for the possible development of FDA guidance documents...

Preamble to marine microbiology: Facets and opportunities

Digital Repository Service at National Institute of Oceanography (India)

Ramaiah, N.

The book titled 'Marine Microbiology: Facets & Opportunities' is an attempt to bring together some facets of marine microbiology as have been made out by many contemporaries in particular from the tropical marine regions. There are 18 contributed...

Production of Probiotic İncir Uyutması Dessert Which Has Functional Properties

Directory of Open Access Journals (Sweden)

Meryem Hut

2013-01-01

Full Text Available In this research, traditional dairy dessert "İncir Uyutması" was produced with different probiotic culture combinations and adding inülin as prebiotic. Produced dessert samples were stored at 5°C for 20 days and determined physical, chemical and microbiological changes during storage. All of the dairy dessert samples had probiotic properties according to microbiological count results and those properties were preserved during storage. During storage, while an important difference didn't become in the dry matter, whey separation and viscosity, important decrease occured in pH. According to the results in this research, probiotic cultures affected physical, chemical and microbiological properties of desserts as positive.

Effect of ultrasound on some chemical and microbiological properties of sour cherry juice by response surface methodology.

Science.gov (United States)

Türken, Tuğba; Erge, Hande S

2017-09-01

In this study, it is aimed to determine effect of ultrasonication on some chemical and microbiological properties of sour cherry juice by response surface methodology, since ultrasound is known as an alternative method for thermal food processing. Sour cherry juice was sonicated at varying amplitude levels (50, 75, 100%); moderate temperatures (20, 30, 40 ℃); and treatment times of 2, 6, 10 min at a constant frequency of 20 kHz. Different ultrasonication amplitudes, temperatures, and times had no significant effect on pH,°Bx, and titratable acidity. A significant increase in total monomeric anthocyanins was observed as the amplitude level and temperature increased (p < 0.01). An increase in the total phenolics was also obtained as the temperature increased (p < 0.05). The effect of amplitude level on antioxidant capacity of sour cherry juice was also found significant (p < 0.05). Color parameters (L*, a*, b*, C, h) generally increased by increasing temperature, amplitude level, and treatment time. It was determined that Escherichia coli O157:H7 significantly affected by temperature and treatment time (p < 0.05).

Rapid and sensitive detection of Pseudomonas aeruginosa in chlorinated water and aerosols targeting gyrB gene using real-time PCR.

Science.gov (United States)

Lee, C S; Wetzel, K; Buckley, T; Wozniak, D; Lee, J

2011-10-01

For the rapid detection of Pseudomonas aeruginosa from chlorinated water and aerosols, gyrB gene-based real-time PCR assay was developed and investigated. Two novel primer sets (pa722F/746MGB/899R and pa722F/746MGB/788R) were designed using the most updated 611 Pseudomonas and 748 other bacterial gyrB genes for achieving high specificity. Their specificity showed 100% accuracy when tested with various strains including clinical isolates from cystic fibrosis patients. The assay was tested with Ps. aeruginosa-containing chlorinated water and aerosols to simulate the waterborne and airborne transmission routes (detection limit 3·3 × 10² CFU per PCR-2·3 × 10³ CFU per PCR). No chlorine interference in real-time PCR was observed at drinking water level (c. 1 mg l⁻¹), but high level of chorine (12 mg l⁻¹) interfered the assay, and thus neutralization was needed. Pseudomonas aeruginosa in aerosol was successfully detected after capturing with gelatin filters with minimum 2 min of sampling time when the initial concentration of 10⁴ CFU ml⁻¹ bacteria existed in the nebulizer. A highly specific and rapid assay (2-3 h) was developed by targeting gyrB gene for the detection of Ps. aeruginosa in chlorinated water and aerosols, combined with optimized sample collection methods and sample processing, so the direct DNA extraction from either water or aerosol was possible while achieving the desired sensitivity of the method.   The new assay can provide timely and accurate risk assessment to prevent Ps. aeruginosa exposure from water and aerosol, resulting in reduced disease burden, especially among immune-compromised and susceptible individuals. This approach can be easily utilized as a platform technology for the detection of other types of micro-organisms, especially for those that are transmitted via water and aerosol routes, such as Legionella pneumophila. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Evaluation of oral microbiology lab curriculum reform.

Science.gov (United States)

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

Medical microbiology training needs and trainee experience.

Science.gov (United States)

Seale, Josephine; Elamin, Wael; Millar, Michael

2014-02-01

Training in microbiology is continuing to evolve. Standardisation of this process has, in part, been achieved through the development of a training curriculum by the Royal College of Pathologists (RCPath). A substantial proportion of microbiology training occurs through telephone consultations. To ascertain the content of these interactions and the extent to which the necessary skills outlined by the curriculum are attainable via these consultations. Records of telephone consultations made by microbiology registrars (SpR) on the Laboratory Information Management System (LIMS) over a 6 month period were analysed with regard to who initiated contact and the type of advice provided. An average of 426 SpR entries per month were made on the LIMS following telephone consultations. These consultations were predominantly initiated by fellow clinicians as opposed to the SpR. The majority (79%) of advice entailed guidance as to the use of antimicrobials which resulted in an alteration of the current regimen in 54% of cases. This study represents the first attempt to quantify the telephone consultations of microbiology trainees. It is concluded that although such interactions provide a means of attaining some of the competencies outlined by the RCPath curriculum, the bias towards antimicrobial advice reflects a discrepancy between the needs of the service users and the broad skill set advocated by the current microbiology training programme. Future modifications will need to take this into account to ensure both the training of SpRs and the microbiology service is fit for purpose.

Detection and Differentiation of Leishmania spp. in Clinical Specimens by Use of a SYBR Green-Based Real-Time PCR Assay.

Science.gov (United States)

de Almeida, Marcos E; Koru, Ozgur; Steurer, Francis; Herwaldt, Barbara L; da Silva, Alexandre J

2017-01-01

Leishmaniasis in humans is caused by Leishmania spp. in the subgenera Leishmania and Viannia Species identification often has clinical relevance. Until recently, our laboratory relied on conventional PCR amplification of the internal transcribed spacer 2 (ITS2) region (ITS2-PCR) followed by sequencing analysis of the PCR product to differentiate Leishmania spp. Here we describe a novel real-time quantitative PCR (qPCR) approach based on the SYBR green technology (LSG-qPCR), which uses genus-specific primers that target the ITS1 region and amplify DNA from at least 10 Leishmania spp., followed by analysis of the melting temperature (T m ) of the amplicons on qPCR platforms (the Mx3000P qPCR system [Stratagene-Agilent] and the 7500 real-time PCR system [ABI Life Technologies]). We initially evaluated the assay by testing reference Leishmania isolates and comparing the results with those from the conventional ITS2-PCR approach. Then we compared the results from the real-time and conventional molecular approaches for clinical specimens from 1,051 patients submitted to the reference laboratory of the Centers for Disease Control and Prevention for Leishmania diagnostic testing. Specimens from 477 patients tested positive for Leishmania spp. with the LSG-qPCR assay, specimens from 465 of these 477 patients also tested positive with the conventional ITS2-PCR approach, and specimens from 10 of these 465 patients had positive results because of retesting prompted by LSG-qPCR positivity. On the basis of the T m values of the LSG-qPCR amplicons from reference and clinical specimens, we were able to differentiate four groups of Leishmania parasites: the Viannia subgenus in aggregate; the Leishmania (Leishmania) donovani complex in aggregate; the species L (L) tropica; and the species L (L) mexicana, L (L) amazonensis, L (L) major, and L (L) aethiopica in aggregate. Copyright © 2016 American Society for Microbiology.

Proteomics in medical microbiology.

Science.gov (United States)

Cash, P

2000-04-01

The techniques of proteomics (high resolution two-dimensional electrophoresis and protein characterisation) are widely used for microbiological research to analyse global protein synthesis as an indicator of gene expression. The rapid progress in microbial proteomics has been achieved through the wide availability of whole genome sequences for a number of bacterial groups. Beyond providing a basic understanding of microbial gene expression, proteomics has also played a role in medical areas of microbiology. Progress has been made in the use of the techniques for investigating the epidemiology and taxonomy of human microbial pathogens, the identification of novel pathogenic mechanisms and the analysis of drug resistance. In each of these areas, proteomics has provided new insights that complement genomic-based investigations. This review describes the current progress in these research fields and highlights some of the technical challenges existing for the application of proteomics in medical microbiology. The latter concern the analysis of genetically heterogeneous bacterial populations and the integration of the proteomic and genomic data for these bacteria. The characterisation of the proteomes of bacterial pathogens growing in their natural hosts remains a future challenge.

European validation of Real-Time PCR method for detection of Salmonella spp. in pork meat.

Science.gov (United States)

Delibato, Elisabetta; Rodriguez-Lazaro, David; Gianfranceschi, Monica; De Cesare, Alessandra; Comin, Damiano; Gattuso, Antonietta; Hernandez, Marta; Sonnessa, Michele; Pasquali, Frédérique; Sreter-Lancz, Zuzsanna; Saiz-Abajo, María-José; Pérez-De-Juan, Javier; Butrón, Javier; Prukner-Radovcic, Estella; Horvatek Tomic, Danijela; Johannessen, Gro S; Jakočiūnė, Džiuginta; Olsen, John E; Chemaly, Marianne; Le Gall, Francoise; González-García, Patricia; Lettini, Antonia Anna; Lukac, Maja; Quesne, Segolénè; Zampieron, Claudia; De Santis, Paola; Lovari, Sarah; Bertasi, Barbara; Pavoni, Enrico; Proroga, Yolande T R; Capuano, Federico; Manfreda, Gerardo; De Medici, Dario

2014-08-01

The classical microbiological method for detection of Salmonella spp. requires more than five days for final confirmation, and consequently there is a need for an alternative methodology for detection of this pathogen particularly in those food categories with a short shelf-life. This study presents an international (at European level) ISO 16140-based validation study of a non-proprietary Real-Time PCR-based method that can generate final results the day following sample analysis. It is based on an ISO compatible enrichment coupled to an easy and inexpensive DNA extraction and a consolidated Real-Time PCR assay. Thirteen laboratories from seven European Countries participated to this trial, and pork meat was selected as food model. The limit of detection observed was down to 10 CFU per 25 g of sample, showing excellent concordance and accordance values between samples and laboratories (100%). In addition, excellent values were obtained for relative accuracy, specificity and sensitivity (100%) when the results obtained for the Real-Time PCR-based methods were compared to those of the ISO 6579:2002 standard method. The results of this international trial demonstrate that the evaluated Real-Time PCR-based method represents an excellent alternative to the ISO standard. In fact, it shows an equal and solid performance as well as it reduces dramatically the extent of the analytical process, and can be easily implemented routinely by the Competent Authorities and Food Industry laboratories. Copyright © 2014 Elsevier B.V. All rights reserved.

21 CFR 866.2900 - Microbiological specimen collection and transport device.

Science.gov (United States)

2010-04-01

... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices... microbiological specimen collection and transport device is a specimen collecting chamber intended for medical...

The Danish Microbiology Database (MiBa) 2010 to 2013

DEFF Research Database (Denmark)

Voldstedlund, M; Haarh, M; Mølbak, K

2014-01-01

The Danish Microbiology Database (MiBa) is a national database that receives copies of reports from all Danish departments of clinical microbiology. The database was launched in order to provide healthcare personnel with nationwide access to microbiology reports and to enable real-time surveillance...

Eliminating PCR contamination

International Nuclear Information System (INIS)

Fox, J.C.; Ait-Khaled, Mounir; Webster, Alison; Emery, V.C.

1991-01-01

The sensitivity of polymerase chain reaction (PCR) can mean that even very low levels of contamination with the target DNA will result in a positive signal. At present this aspect is a major limitation in the use of PCR as a routine diagnostic method. By exposing PCR reagents to UV light, contaminating DNA can be inactivated, thus providing an opportunity to eradicate false positive reactions. UV irradiation was applied to PCR systems used for detection of human cytomegalovirus CMV and human immunodeficiency virus (HIV) and shown to be effective in eradicating both laboratory encountered contamination and plasmid DNA (below 100 pg) added to PCR systems prior to UV exposure. Sensitivity of a PCR system to amplify the long terminal repeat (LTR) sequence of HIV-1 was not affected by the irradiation procedure; however, ultimate sensitivity of a PCR system for the amplification of an early gene pro-motor sequence of the CMV genome was reduced 1000-fold. UV irradiation did not affect the size of the PCR product as determined by strand separating polyacrylamide gel electrophoresis of a 32 P-labelled amplimer. Thus, a simple pre-exposure to UV light would seem a worth-wile step to incorporate into PCR protocols provided that the effects on sensitivity have been determined empirically for each PCR system. (author). 11 refs.; 3 figs

Application of clone library analysis and real-time PCR for comparison of microbial communities in a low-grade copper sulfide ore bioheap leachate.

Science.gov (United States)

Bowei, Chen; Xingyu, Liu; Wenyan, Liu; Jiankang, Wen

2009-11-01

The microbial communities of leachate from a bioleaching heap located in China were analyzed using the 16S rRNA gene clone library and real-time quantitative PCR. Both methods showed that Leptospirillum spp. were the dominant bacteria, and Ferroplasma acidiphilum were the only archaea detected in the leachate. Clone library results indicated that nine operational taxonomic units (OTUs) were obtained, which fell into four divisions, the Nitrospirae (74%), the gamma-Proteobacteria (14%), the Actinobacteria (6%) and the Euryarchaeota (6%). The results obtained by real-time PCR in some ways were the same as clone library analysis. Furthermore, Sulfobacillus spp., detected only by real-time PCR, suggests that real-time PCR was a reliable technology to study the microbial communities in bioleaching environments. It is a useful tool to assist clone library analysis, to further understand microbial consortia and to have comprehensive and exact microbiological information about bioleaching environments. Finally, the interactions among the microorganisms detected in the leachate were summarized according to the characteristics of these species.

Performance of a real-time PCR assay in routine bovine mastitis diagnostics compared with in-depth conventional culture.

Science.gov (United States)

Hiitiö, Heidi; Riva, Rauna; Autio, Tiina; Pohjanvirta, Tarja; Holopainen, Jani; Pyörälä, Satu; Pelkonen, Sinikka

2015-05-01

Reliable identification of the aetiological agent is crucial in mastitis diagnostics. Real-time PCR is a fast, automated tool for detecting the most common udder pathogens directly from milk. In this study aseptically taken quarter milk samples were analysed with a real-time PCR assay (Thermo Scientific PathoProof Mastitis Complete-12 Kit, Thermo Fisher Scientific Ltd.) and by semi-quantitative, in-depth bacteriological culture (BC). The aim of the study was to evaluate the diagnostic performance of the real-time PCR assay in routine use. A total of 294 quarter milk samples from routine mastitis cases were cultured in the national reference laboratory of Finland and examined with real-time PCR. With BC, 251 out of 294 (85.7%) of the milk samples had at least one colony on the plate and 38 samples were considered contaminated. In the PCR mastitis assay, DNA of target species was amplified in 244 samples out of 294 (83.0%). The most common bacterial species detected in the samples, irrespective of the diagnostic method, was the coagulase negative staphylococci (CNS) group (later referred as Staphylococcus spp.) followed by Staphylococcus aureus. Sensitivity (Se) and specificity (Sp) for the PCR assay to provide a positive Staph. aureus result was 97.0 and 95.8% compared with BC. For Staphylococcus spp., the corresponding figures were 86.7 and 75.4%. Our results imply that PCR performed well as a diagnostic tool to detect Staph. aureus but may be too nonspecific for Staphylococcus spp. in routine use with the current cut-off Ct value (37.0). Using PCR as the only microbiological method for mastitis diagnostics, clinical relevance of the results should be carefully considered before further decisions, for instance antimicrobial treatment, especially when minor pathogens with low amount of DNA have been detected. Introducing the concept of contaminated samples should also be considered.

Enzymatic and viability RT-qPCR assays for evaluation of enterovirus, hepatitis A virus and norovirus inactivation: Implications for public health risk assessment.

Science.gov (United States)

Monteiro, S; Santos, R

2018-04-01

To assess the potential of a viability dye and an enzymatic reverse transcription quantitative PCR (RT-qPCR) pretreatment to discriminate between infectious and noninfectious enteric viruses. Enterovirus (EntV), norovirus (NoV) GII.4 and hepatitis A virus (HAV) were inactivated at 95°C for 10 min, and four methods were used to compare the efficiency of inactivation: (i) cell culture plaque assay for HAV and EntV, (ii) RT-qPCR alone, (iii) RT-qPCR assay preceded by RNase treatment, and (iv) pretreatment with a viability dye (reagent D (RD)) followed by RT-qPCR. In addition, heat-inactivated NoV was treated with RD coupled with surfactants to increase the efficiency of the viability dye. No treatment was able to completely discriminate infectious from noninfectious viruses. RD-RT-qPCR reduced more efficiently the detection of noninfectious viruses with little to no removal observed with RNase. RD-RT-qPCR method was the closest to cell culture assay. The combination of surfactants and RD did not show relevant improvements on the removal of inactivated viruses signal compared with viability RT-qPCR, with the exception of Triton X-100. The use of surfactant/RD-RT-qPCR, although not being able to completely remove the signal from noninfectious viral particles, yielded a better estimation of viral infectivity. Surfactant/RD-RT-qPCR may be an advantageous tool for a better detection of infectious viruses with potential significant impact in the risk assessment of the presence of enteric viruses. © 2017 The Society for Applied Microbiology.

Microbiologically Influenced Corrosion

Science.gov (United States)

2009-01-01

species grow as multicel- lular filaments called hyphae forming a mycelium, some fungal species also grow as single cells. Sexual and asexual...reinforced fluorinated 18 MICROBIOLOGICALLY INFLUENCED CORROSION polyimide composites due to hyphae penetration into resin interiors. The

Manual de microbiología

OpenAIRE

Montoya Campuzano, Olga Inés

1999-01-01

Resumen: el manual de microbiología general fue elaborado con el objetivo de proporcionarle al estudiante de Zootecnia de la Universidad Nacional, las técnicas básicas en microbiología, de interés para aquellos cursos que 10 requieren. El estudiante trabajara con los microorganismos (patógenos y no patógenos de importancia, en las áreas de asistencia técnica que le corresponde prestar como: calidad de agua, de alimentos, de Semen entre otras

Clinical and Microbiological Aspects of β-Lactam Resistance in Staphylococcus lugdunensis.

Science.gov (United States)

McHardy, Ian H; Veltman, Jennifer; Hindler, Janet; Bruxvoort, Katia; Carvalho, Marissa M; Humphries, Romney M

2017-02-01

Antimicrobial susceptibility results from broth microdilution MIC testing of 993 Staphylococcus lugdunensis isolates recovered from patients at a tertiary care medical center from 2008 to 2015 were reviewed. Ninety-two oxacillin-susceptible isolates were selected to assess the accuracy of penicillin MIC testing, the penicillin disk diffusion test, and three β-lactamase tests, including the cefoxitin-induced nitrocefin test, penicillin cloverleaf assay, and penicillin disk zone edge test. The results of all phenotypic tests were compared to the results of blaZ PCR. The medical records of 62 patients from whom S. lugdunensis was isolated, including 31 penicillin-susceptible and 31 penicillin-resistant strains, were retrospectively reviewed to evaluate the clinical significance of S. lugdunensis isolation, the antimicrobial agents prescribed, if any, and the clinical outcome. MIC testing revealed that 517/993 (52.1%) isolates were susceptible to penicillin and 946/993 (95.3%) were susceptible to oxacillin. The induced nitrocefin test was 100% sensitive and specific for the detection of β-lactamase compared to the blaZ PCR results, whereas the penicillin disk zone edge and cloverleaf tests showed sensitivities of 100% but specificities of only 9.1% and 89.1%, respectively. The penicillin MIC test had 100% categorical agreement with blaZ PCR, while penicillin disk diffusion yielded one major error. Only 3/31 patients with penicillin-susceptible isolates were treated with a penicillin family antimicrobial. The majority of cases were treated with other β-lactams, trimethoprim-sulfamethoxazole, or vancomycin. These data indicate that nearly all isolates of S. lugdunensis are susceptible to narrow-spectrum antimicrobial agents. Clinical laboratories in areas with resistance levels similar to those described here can help promote the use of these agents versus vancomycin by effectively designing their antimicrobial susceptibility reports to convey this message. Copyright

Real-Time PCR (qPCR) Primer Design Using Free Online Software

Science.gov (United States)

Thornton, Brenda; Basu, Chhandak

2011-01-01

Real-time PCR (quantitative PCR or qPCR) has become the preferred method for validating results obtained from assays which measure gene expression profiles. The process uses reverse transcription polymerase chain reaction (RT-PCR), coupled with fluorescent chemistry, to measure variations in transcriptome levels between samples. The four most…

Application of reverse transcription-PCR and real-time PCR in nanotoxicity research.

Science.gov (United States)

Mo, Yiqun; Wan, Rong; Zhang, Qunwei

2012-01-01

Reverse transcription-polymerase chain reaction (RT-PCR) is a relatively simple and inexpensive technique to determine the expression level of target genes and is widely used in biomedical science research including nanotoxicology studies for semiquantitative analysis. Real-time PCR allows for the detection of PCR amplification in the exponential growth phase of the reaction and is much more quantitative than traditional RT-PCR. Although a number of kits and reagents for RT-PCR and real-time PCR are commercially available, the basic principles are the same. Here, we describe the procedures for total RNA isolation by using TRI Reagent, for reverse transcription (RT) by M-MLV reverse transcriptase, and for PCR by GoTaq(®) DNA Polymerase. And real-time PCR will be performed on an iQ5 multicolor real-time PCR detection system by using iQ™ SYBR Green Supermix.

Lower antibiotic costs attributable to clinical microbiology rounds.

Science.gov (United States)

Huang, Richard S P; Guervil, David J; Hunter, Robert L; Wanger, Audrey

2015-09-01

At our institution, our microbiologist, pharmacist, and infectious disease (ID) team meet to discuss ID patients, and this meeting is referred to as microbiology rounds. We hypothesized that our microbiology rounds reduce antibiotic costs. The study involved a review of 80 patients with an ID consultation order at each of the 3 hospitals: hospital A (HA) (only HA has microbiology rounds), hospital B (HB), and hospital C (HC). Of this population, we included patients with a positive blood culture. Thirty-six patients who met the above criteria were included in the study. The average antibiotic cost/patient/day at HA, HB, and HC were $66.0, $123, and $109, respectively. Also, we found that change in antibiotics was appropriate when compared to the final microbiology results in 90%, 44%, and 40% of the time at HA, HB, and HC, respectively. Herein, we found an association between conducting microbiology rounds and reduction of antibiotic cost. Copyright © 2015 Elsevier Inc. All rights reserved.

Microbiological, chemical and physical quality of drinking water for commercial turkeys: a cross-sectional study.

Science.gov (United States)

Di Martino, G; Piccirillo, A; Giacomelli, M; Comin, D; Gallina, A; Capello, K; Buniolo, F; Montesissa, C; Bonfanti, L

2018-04-17

Drinking water for poultry is not subject to particular microbiological, chemical and physical requirements, thereby representing a potential transmission route for pathogenic microorganisms and contaminants and/or becoming unsuitable for water-administered medications. This study assessed the microbiological, chemical and physical drinking water quality of 28 turkey farms in North-Eastern Italy: 14 supplied with tap water (TW) and 14 with well water (WW). Water salinity, hardness, pH, ammonia, sulphate, phosphate, nitrate, chromium, copper and iron levels were also assessed. Moreover, total bacterial count at 22°C, presence and enumeration of Enterococcus spp. and E. coli, presence of Salmonella spp. and Campylobacter spp. were quantified. A water sample was collected in winter and in summer at 3 sampling sites: the water source (A), the beginning (B) and the end (C) of the nipple line (168 samples in total). Chemical and physical quality of both TW and WW sources was mostly within the limits of TW for humans. However, high levels of hardness and iron were evidenced in both sources. In WW vs. TW, sulphate and salinity levels were significantly higher, whilst pH and nitrate levels were significantly lower. At site A, microbiological quality of WW and TW was mostly within the limit of TW for humans. However, both sources had a significantly lower microbiological quality at sites B and C. Salmonella enterica subsp. enterica serotype Kentucky was isolated only twice from WW. Campylobacter spp. were rarely isolated (3.6% of farms); however, Campylobacter spp. farm-level prevalence by real-time PCR was up to 43% for both water sources. Winter posed at higher risk than summer for Campylobacter spp. presence in water, whereas no significant associations were found with water source, site, recirculation system, and turkey age. Low salinity and high hardness were significant risk factors for C. coli and C. jejuni presence, respectively. These results show the need of

[Safety in the Microbiology laboratory].

Science.gov (United States)

Rojo-Molinero, Estrella; Alados, Juan Carlos; de la Pedrosa, Elia Gómez G; Leiva, José; Pérez, José L

2015-01-01

The normal activity in the laboratory of microbiology poses different risks - mainly biological - that can affect the health of their workers, visitors and the community. Routine health examinations (surveillance and prevention), individual awareness of self-protection, hazard identification and risk assessment of laboratory procedures, the adoption of appropriate containment measures, and the use of conscientious microbiological techniques allow laboratory to be a safe place, as records of laboratory-acquired infections and accidents show. Training and information are the cornerstones for designing a comprehensive safety plan for the laboratory. In this article, the basic concepts and the theoretical background on laboratory safety are reviewed, including the main legal regulations. Moreover, practical guidelines are presented for each laboratory to design its own safety plan according its own particular characteristics. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

21 CFR 866.2350 - Microbiological assay culture medium.

Science.gov (United States)

2010-04-01

... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2350... consists primarily of liquid or solid biological materials intended for medical purposes to cultivate...

Physicochemical, microbiological and sensory evaluation of a bioactive food blend

Directory of Open Access Journals (Sweden)

Rosângela dos Santos Ferreira

2014-09-01

Full Text Available The potential of functional foods to decrease the risks of chronic non-communicable diseases has motivated the development of products with beneficial effects on fat and carbohydrate metabolism. The present study aimed at analyzing the physicochemical, microbiological, and sensory properties of a bioactive food blend developed to help the nutritional therapy provided to hypolipidemic and hyperglycemic patients with HIV/AIDS treated with antiretroviral therapy. The food blend was evaluated for moisture, protein, carbohydrate, fats, fixed mineral residue, total fiber content, and fatty acid composition, according to the standards established by the Instituto Adolfo Lutz. Food safety was assessed by microbiological analyses for Bacillus cereus, Salmonella spp, and coliforms. Sensory acceptance and intention to purchase were also evaluated. The food blend showed good nutritional potential, with low atherogenicity and thrombogenicity indexes, good macronutrient balance, and high energy value. The adoption of Good Manufacturing Practices (GMP resulted in a product suitable for consumption. With respect to sensory aspects, the food blend showed satisfactory indexes of acceptability and promising marketing potential.

Physicochemical Characteristics and Microbiological Quality of Honey Produced in Benin

Directory of Open Access Journals (Sweden)

François Ezin Azonwade

2018-01-01

Full Text Available Honey is a very complex biological product. It has great diversity, giving it a multitude of properties, both nutritionally and therapeutically. This study aimed to study the physicochemical and microbiological characteristics of honeys collected during the dry and rainy seasons in the different phytogeographical areas of Benin. The study revealed that all honeys had pH, water content, electrical conductivity, ash content, free acidity, total sugars, and reducing sugars, respectively, ranging within 3.65–4.09; 12.07–13.16%; 530.25–698.50 μs/cm; 0.42–0.53%; 35.67–40.52 meq/kg; 60–70%; and 58–70%. Moisture content, total sugars, and reducing sugars varied very significantly (p0.05 between the zones or between the seasons was observed. The results of the microbiological characterization showed that there is heterogeneity in the microbial load. These results have shown that these honeys meet international standards and their characterization will make it possible to obtain Beninese quality labels.

Molecular detection and species-specific identification of medically important Aspergillus species by real-time PCR in experimental invasive pulmonary aspergillosis.

Science.gov (United States)

Walsh, Thomas J; Wissel, Mark C; Grantham, Kevin J; Petraitiene, Ruta; Petraitis, Vidmantas; Kasai, Miki; Francesconi, Andrea; Cotton, Margaret P; Hughes, Johanna E; Greene, Lora; Bacher, John D; Manna, Pradip; Salomoni, Martin; Kleiboeker, Steven B; Reddy, Sushruth K

2011-12-01

Diagnosis of invasive pulmonary aspergillosis (IPA) remains a major challenge to clinical microbiology laboratories. We developed rapid and sensitive quantitative PCR (qPCR) assays for genus- and species-specific identification of Aspergillus infections by use of TaqMan technology. In order to validate these assays and understand their potential diagnostic utility, we then performed a blinded study of bronchoalveolar lavage (BAL) fluid specimens from well-characterized models of IPA with the four medically important species. A set of real-time qPCR primers and probes was developed by utilizing unique ITS1 regions for genus- and species-specific detection of the four most common medically important Aspergillus species (Aspergillus fumigatus, A. flavus, A. niger, and A. terreus). Pan-Aspergillus and species-specific qPCRs with BAL fluid were more sensitive than culture for detection of IPA caused by A. fumigatus in untreated (P < 0.0007) and treated (P ≤ 0.008) animals, respectively. For infections caused by A. terreus and A. niger, culture and PCR amplification from BAL fluid yielded similar sensitivities for untreated and treated animals. Pan-Aspergillus PCR was more sensitive than culture for detection of A. flavus in treated animals (P = 0.002). BAL fluid pan-Aspergillus and species-specific PCRs were comparable in sensitivity to BAL fluid galactomannan (GM) assay. The copy numbers from the qPCR assays correlated with quantitative cultures to determine the pulmonary residual fungal burdens in lung tissue. Pan-Aspergillus and species-specific qPCR assays may improve the rapid and accurate identification of IPA in immunocompromised patients.

THE MICROBIOLOGY OF SOUTH AFRICAN DRIED SAUSAGE

African Journals Online (AJOL)

THE MICROBIOLOGY OF SOUTH AFRICAN DRIED SAUSAGE. W.H. Holzapfel and A.N. Hail. Receipt of MS s.3.76. Department of Microbiology and Plant Pathology, University of hetoria and. Animol and Dairv Science Reseorch Institute, Irene. OPSOMMING: DIE MIKROBIOLOGIE VAN SUID.AFRIKAANSE DROiWORS.

Advances in the application of molecular microbiological methods in the oil and gas industry and links to microbiologically influenced corrosion

DEFF Research Database (Denmark)

Eckert, Rickard; Skovhus, Torben Lund

2018-01-01

While the oil and gas industry has witnessed increased applications of molecular microbiological methods (MMMs) for diagnosing and managing microbiologically influenced corrosion (MIC) in the past decade, the process for establishing clear links between microbiological conditions and corrosion...... mechanisms is still emerging. Different MMMs provide various types of information about microbial diversity, abundance, activity and function, all of which are quite different from the culture-based results that are familiar to oil and gas industry corrosion professionals. In addition, a multidisciplinary...

Radiation processing of minimally processed fruits and vegetables to ensure microbiological safety

International Nuclear Information System (INIS)

Bandekar, J.R.; Saroj, S.D.; Shashidhar, R.; Dhokane, V.S.; Hajare, S.N.; Nagar, V.; Sharma, A.

2009-01-01

Minimally processed fruits and vegetables are in demand as they offer ready rich source of nutrients and convenience to consumers. However, these products are often unsafe due to contamination with harmful pathogens. Therefore, a study was carried out to analyze microbiological quality of minimally processed fruits, vegetables and sprouts and to optimize radiation dose necessary to ensure safety of these commodities. Microbiological quality of these products was found to be poor. Decimal reduction dose (D 10 ) for Salmonella Typhimurium and Listeria monocytogenes in these minimally processed foods (MPF) were in the range of 164 to 588 Gy. Radiation processing with 2 kGy dose of gamma radiation resulted in 5 log reduction of S. Typhimurium and 4 log reduction of L. monocytogenes. The treatment did not significantly affect nutritional, organoleptic and textural properties. These results suggest that radiation processing can ensure safety of these products. (author)

Yeast identification by sequencing, biochemical kits, MALDI-TOF MS and rep-PCR DNA fingerprinting.

Science.gov (United States)

Zhao, Ying; Tsang, Chi-Ching; Xiao, Meng; Chan, Jasper F W; Lau, Susanna K P; Kong, Fanrong; Xu, Yingchun; Woo, Patrick C Y

2017-12-08

No study has comprehensively evaluated the performance of 28S nrDNA and ITS sequencing, commercial biochemical test kits, MALDI-TOF MS platforms, and the emerging rep-PCR DNA fingerprinting technology using a cohort of yeast strains collected from a clinical microbiology laboratory. In this study, using 71 clinically important yeast isolates (excluding Candida albicans) collected from a single centre, we determined the concordance of 28S nrDNA and ITS sequencing and evaluated the performance of two commercial test kits, two MALDI-TOF MS platforms, and rep-PCR DNA fingerprinting. 28S nrDNA and ITS sequencing showed complete agreement on the identities of the 71 isolates. Using sequencing results as the standard, 78.9% and 71.8% isolates were correctly identified using the API 20C AUX and Vitek 2 YST ID Card systems, respectively; and 90.1% and 80.3% isolates were correctly identified using the Bruker and Vitek MALDI-TOF MS platforms, respectively. Of the 18 strains belonging to the Candida parapsilosis species complex tested by DiversiLab automated rep-PCR DNA fingerprinting, all were identified only as Candida parapsilosis with similarities ≥93.2%, indicating the misidentification of Candida metapsilosis and Candida orthopsilosis. However, hierarchical cluster analysis of the rep-PCR DNA fingerprints of these three species within this species complex formed three different discrete clusters, indicating that this technology can potentially differentiate the three species. To achieve higher accuracies of identification, the databases of commercial biochemical test kits, MALDI-TOF MS platforms, and DiversiLab automated rep-PCR DNA fingerprinting needs further enrichment, particularly for uncommonly encountered yeast species. © The Author 2017. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Physicochemical and microbiological factors influencing the bioavailability of organic contaminants in subsoils

International Nuclear Information System (INIS)

1992-01-01

We report progress in elucidating the microbiological variables important in determining the relative success of bacteria in utilizing soil-sorbed contaminants. Two bacterial species, Pseudomonas putida (ATCC 17484) and an Alcaligenes sp. isolated from petroleum contaminated soil are known to differ markedly in their ability to utilize soil-sorbed napthalene based on a kinetic comparison of their capability of naphthalene mineralization in soil-containing and soil-free systems. The kinetic analysis led us to conclude that strain 17484 had direct access to naphthalene present in a labile sorbed state which promoted the rapid desorption of naphthalene from the non-labile phase. Conversely, both the rate and extent of naphthalene mineralization by strain NP-Alk suggested that this organism had access only to naphthalene in solution. Desorption was thus limited and the efficiency of total naphthalene removal from these soil slurries was poor. These conclusions were based on the average activities of cells in soil slurries without regard for the disposition of the organisms with respect to the sorbent. Since both organisms degrade naphthalene by apparently identical biochemical pathways, have similar enzyme kinetic properties, and are both motile, gram negative organisms, we undertook a series of investigations to gain a better understanding of what microbiological properties were important in bioavailability

Diagnostic microbiology in veterinary dermatology: present and future.

Science.gov (United States)

Guardabassi, Luca; Damborg, Peter; Stamm, Ivonne; Kopp, Peter A; Broens, Els M; Toutain, Pierre-Louis

2017-02-01

The microbiology laboratory can be perceived as a service provider rather than an integral part of the healthcare team. The aim of this review is to discuss the current challenges of providing a state-of-the-art diagnostic veterinary microbiology service including the identification (ID) and antimicrobial susceptibility testing (AST) of key pathogens in veterinary dermatology. The Study Group for Veterinary Microbiology (ESGVM) of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) identified scientific, technological, educational and regulatory issues impacting the predictive value of AST and the quality of the service offered by microbiology laboratories. The advent of mass spectrometry has significantly reduced the time required for ID of key pathogens such as Staphylococcus pseudintermedius. However, the turnaround time for validated AST methods has remained unchanged for many years. Beyond scientific and technological constraints, AST methods are not harmonized and clinical breakpoints for some antimicrobial drugs are either missing or inadequate. Small laboratories, including in-clinic laboratories, are usually not adequately equipped to run up-to-date clinical microbiologic diagnostic tests. ESGVM recommends the use of laboratories employing mass spectrometry for ID and broth micro-dilution for AST, and offering assistance by expert microbiologists on pre- and post-analytical issues. Setting general standards for veterinary clinical microbiology, promoting antimicrobial stewardship, and the development of new, validated and rapid diagnostic methods, especially for AST, are among the missions of ESGVM. © 2017 The Authors. Veterinary Dermatology published by John Wiley & Sons Ltd on behalf of the ESVD and ACVD.

Comparison of false-negative rates and limits of detection following macrofoam-swab sampling of Bacillus anthracis surrogates via Rapid Viability PCR and plate culture.

Science.gov (United States)

Hutchison, J R; Piepel, G F; Amidan, B G; Hess, B M; Sydor, M A; Deatherage Kaiser, B L

2018-05-01

We evaluated the effects of Bacillus anthracis surrogates, low surface concentrations, surface materials and assay methods on false-negative rate (FNR) and limit of detection (LOD 95 ) for recovering Bacillus spores using a macrofoam-swab sampling procedure. Bacillus anthracis Sterne or Bacillus atrophaeus Nakamura spores were deposited over a range of low target concentrations (2-500 per coupon) onto glass, stainless steel, vinyl tile and plastic. Samples were assayed using a modified Rapid Viability-PCR (mRV-PCR) method and the traditional plate culture method to obtain FNR and LOD 95 results. Mean FNRs tended to be lower for mRV-PCR compared to culturing, and increased as spore concentration decreased for all surface materials. Surface material, but not B. anthracis surrogate, influenced FNRs with the mRV-PCR method. The mRV-PCR LOD 95 was lowest for glass and highest for vinyl tile. LOD 95 values overall were lower for mRV-PCR than for the culture method. This study adds to the limited data on FNR and LOD 95 for mRV-PCR and culturing methods with low concentrations of B. anthracis sampled from various surface materials by the CDC macrofoam-swab method. These are key inputs for planning characterization and clearance studies for low contamination levels of B. anthracis. © 2018 The Society for Applied Microbiology.

[Retrospective study of the implementation of the qualitative PCR technique in biological samples for monitoring toxoplasmosis in pediatric patients receiving hematopoietic stem cell transplantation].

Science.gov (United States)

Nigro, Mónica G; Figueroa, Carlos; Ledesma, Bibiana A

2014-01-01

Toxoplasmosis is an opportunistic infection caused by the parasite Toxoplasma gondii. The infection is severe and difficult to diagnose in patients receiving allogeneic hematopoietic stem cell transplantation (HSCT). Twelve patients receiving HSCT were monitored post-transplant, by qualitative PCR at the Children's Hospital S.A.M.I.C. "Prof. Dr. Juan P. Garrahan". The monitoring of these patients was defined by a history of positive serology for toxoplasmosis in the donor or recipient and because their hematologic condition did not allow the use of trimethoprim-sulfamethoxazole for prophylaxis. During the patients' monitoring, two of them with positive PCR results showed signs of illness by T. gondii and were treated with pyrimethamine-clindamycin. In two other patients, toxoplasmosis was the cause of death and an autopsy finding, showing negative PCR results. Four patients without clinical manifestations received treatment for toxoplasmosis because of positive PCR detection. In four patients there were no signs of toxoplasmosis disease and negative PCR results during follow-up. The qualitative PCR technique proved useful for the detection of toxoplasmosis reactivation in HSCT recipients, but has limitations in monitoring and making clinical decisions due to the persistence of positive PCR over time and manifestations of toxicity caused by the treatment. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

Evaluation of DNA extraction methods for PCR-based detection of Listeria monocytogenes from vegetables.

Science.gov (United States)

Vojkovska, H; Kubikova, I; Kralik, P

2015-03-01

Epidemiological data indicate that raw vegetables are associated with outbreaks of Listeria monocytogenes. Therefore, there is a demand for the availability of rapid and sensitive methods, such as PCR assays, for the detection and accurate discrimination of L. monocytogenes. However, the efficiency of PCR methods can be negatively affected by inhibitory compounds commonly found in vegetable matrices that may cause false-negative results. Therefore, the sample processing and DNA isolation steps must be carefully evaluated prior to the introduction of such methods into routine practice. In this study, we compared the ability of three column-based and four magnetic bead-based commercial DNA isolation kits to extract DNA of the model micro-organism L. monocytogenes from raw vegetables. The DNA isolation efficiency of all isolation kits was determined using a triplex real-time qPCR assay designed to specifically detect L. monocytogenes. The kit with best performance, the PowerSoil(™) Microbial DNA Isolation Kit, is suitable for the extraction of amplifiable DNA from L. monocytogenes cells in vegetable with efficiencies ranging between 29.6 and 70.3%. Coupled with the triplex real-time qPCR assay, this DNA isolation kit is applicable to the samples with bacterial loads of 10(3) bacterial cells per gram of L. monocytogenes. Several recent outbreaks of Listeria monocytogenes have been associated with the consumption of fruits and vegetables. Real-time PCR assays allow fast detection and accurate quantification of microbes. However, the success of real-time PCR is dependent on the success with which template DNA can be extracted. The results of this study suggest that the PowerSoil(™) Microbial DNA Isolation Kit can be used for the extraction of amplifiable DNA from L. monocytogenes cells in vegetable with efficiencies ranging between 29.6 and 70.3%. This method is applicable to samples with bacterial loads of 10(3) bacterial cells per gram of L. monocytogenes. © 2014

Practical microbiology in schools: a survey of UK teachers.

Science.gov (United States)

Redfern, James; Burdass, Dariel; Verran, Joanna

2013-11-01

A survey of secondary school teachers investigated practical microbiology in the classroom. The results were heartening (practical microbiology was common), but concerns were expressed regarding equipment, time, cost, and expertise. Microbiologists should engage more with school education to support teachers and maintain the health of microbiology for future generations. Copyright © 2013 Elsevier Ltd. All rights reserved.

[Publication rates of Turkish medical specialty and doctorate theses on Medical Microbiology, Clinical Microbiology and Infectious Diseases disciplines in international journals].

Science.gov (United States)

Sipahi, Oğuz Reşat; Caglayan Serin, Derya; Pullukcu, Hüsnü; Tasbakan, Meltem; Köseli Ulu, Demet; Yamazhan, Tansu; Arda, Bilgin; Sipahi, Hilal; Ulusoy, Sercan

2014-04-01

Writing a thesis is mandatory for getting a postgraduate medical degree in Turkey. Publication of the results of the thesis in an indexed journal makes the results available to researchers, however publication rate is usually low. The aim of this retrospective observational study was to investigate the publication rate of Turkish Infectious Diseases and Clinical Microbiology, Medical Microbiology specialty theses and Microbiology doctorate theses in international peer-review journals. On August 17th 2007, the thesis database of the Council of Higher Education of the Republic of Turkey (YOK) where all specialization and doctorate theses are recorded obligatorily, was searched for Infectious Diseases and Clinical Microbiology and Medical Microbiology specialty and Microbiology doctorate theses. Assuming that publication of a thesis would last at least six months, theses dated to February 2007 and after were excluded. The publication rate of those theses was found out by searching Science Citation Index-Expanded database for thesis author and supervisor between August 17-September 12, 2007. Chi-square test was used for statistical analysis. Our search yielded a total of 834 theses dated from 1997 to 2007, however 10 of them were excluded, since they were dated to February 2007 or after. It was found that the overall publication rate was 11.4% (94/824). The publication rates for Microbiology doctorate, Medical Microbiology and Infectious Diseases and Clinical Microbiology specialty theses were 13.7% (34/249), 10.7% (33/309) and 10.2% (27/266), respectively, with no statistical significance (p> 0.05). It was determined that nine (9.6%) of the 94 published theses belonged to 1997-2001 period, whereas 85 (80.4%) were in 2002-2007 period (p< 0.05). The probable reason for this increase was thought to be related with the updated criteria of YOK carried out in 2000 for academic promotions, nevertheless the publication rate of the investigated theses in international peer

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

Science.gov (United States)

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.

Enhancing Engineering Students’ Learning in an Environmental Microbiology Course

Directory of Open Access Journals (Sweden)

Zhi Zhou

2012-08-01

Full Text Available While environmental engineering students have gained some knowledge of biogeochemical cycles and sewage treatment, most of them haven’t learned microbiology previously and usually have difficulty in learning environmental microbiology because microbiology deals with invisible living microorganisms instead of visible built environment. Many teaching techniques can be used to enhance students’ learning in microbiology courses, such as lectures, animations, videos, small-group discussions, and active learning techniques. All of these techniques have been applied in the engineering class, but the results indicate that these techniques are often inadequate for students. Learning difficulties have to be identified to enhance students’ learning.

Effects of different packaging techniques on the microbiological and physicochemical properties of coated pumpkin slices

Directory of Open Access Journals (Sweden)

Filiz AKSU

2016-01-01

Full Text Available Abstract In this study the effects of zein film coating along with benzoic acid on the quality of sliced pumpkin samples, which were packaged with different techniques were investigated. The samples were allocated into different groups and were treated with different processes. Following processing, the samples were stored at +4 °C for twenty days. Physicochemical and microbiological analyses were carried out on the samples once every five days during the storage period. According to color analysis, the L* value was observed to have significantly decreased in the processed and packaged samples in comparison with the control group. Besides, a* and b* values increased in all groups. It was determined that zein film alone did not exhibit the expected effectiveness against moisture loss in the samples. According to the results of microbiological analysis, a final decrease at approximately 1.00 log level was determined in total count of mesophilic aerobic bacteria (TMAB in the group which was vacuum packaged in PVDC with zein coating when compared with the initial TMAB. Furthermore, no molding occurred in zein-coated group on the last day of the storage period, while massive mold growth was noted in the group which was packaged without any pretreatment procedure.

Detection of Tilapia Lake Virus in Clinical Samples by Culturing and Nested Reverse Transcription-PCR.

Science.gov (United States)

Kembou Tsofack, Japhette Esther; Zamostiano, Rachel; Watted, Salsabeel; Berkowitz, Asaf; Rosenbluth, Ezra; Mishra, Nischay; Briese, Thomas; Lipkin, W Ian; Kabuusu, Richard M; Ferguson, Hugh; Del Pozo, Jorge; Eldar, Avi; Bacharach, Eran

2017-03-01

Tilapia are an important group of farmed fish that serve as a significant protein source worldwide. In recent years, substantial mortality of wild tilapia has been observed in the Sea of Galilee and in commercial ponds in Israel and Ecuador. We have identified the etiological agent of these mass die-offs as a novel orthomyxo-like virus and named it tilapia lake virus (TiLV). Here, we provide the conditions for efficient isolation, culturing, and quantification of the virus, including the use of susceptible fish cell lines. Moreover, we describe a sensitive nested reverse transcription-PCR (RT-PCR) assay allowing the rapid detection of TiLV in fish organs. This assay revealed, for the first time to our knowledge, the presence of TiLV in diseased Colombian tilapia, indicating a wider distribution of this emerging pathogen and stressing the risk that TiLV poses for the global tilapia industry. Overall, the described procedures should provide the tilapia aquaculture industry with important tools for the detection and containment of this pathogen. Copyright © 2017 American Society for Microbiology.

Quality control for diagnostic oral microbiology laboratories in European countries

NARCIS (Netherlands)

Rautemaa-Richardson, R.; van der Reijden, W.A.; Dahlen, G.; Smith, A.J.

2011-01-01

Participation in diagnostic microbiology internal and external quality control (QC) processes is good laboratory practice and an essential component of a quality management system. However, no QC scheme for diagnostic oral microbiology existed until 2009 when the Clinical Oral Microbiology (COMB)

Gamma radiation effects on microbiological, physico-chemical and antioxidant properties of Tunisian millet (Pennisetum Glaucum L.R.Br.).

Science.gov (United States)

Ben Mustapha, Maha; Bousselmi, Mehrez; Jerbi, Taïeb; Ben Bettaïeb, Nasreddine; Fattouch, Sami

2014-07-01

Hygienic quality of Tunisian pearl millet flour is always of major concern to consumers as well as all involved in the production, processing and distribution sectors. In the present study, the microbiological and biochemical properties of this food were examined following gamma-radiation. The D10-values for the Total Aerobic Plate Count, yeasts and moulds were respectively 1.5 and 3.7kGy. Furthermore, millet flour is commonly susceptible to mycotoxin contaminations, so the Ochratoxin A residues were also investigated; a reduction of 74% was observed with 10kGy. Moreover, the radiation process did not significantly alter fatty acids composition of the millet flour as obtained with Gas chromatography-flame ionisation detector technic. The peroxide value had increased from 26.16 to 34.43meqO2/kg with 3kGy. At 1kGy, we noticed an important loss of vitamin A of about 88.6%. In contrast, the total phenolic content, the ABTS-RSA and the DPPH-RSA of the radiated millet flour exhibited non-significant changes (p<0.05). Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

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.

Aspergillus Galactomannan Enzyme Immunoassay and Quantitative PCR for Diagnosis of Invasive Aspergillosis with Bronchoalveolar Lavage Fluid

Science.gov (United States)

Musher, Benjamin; Fredricks, David; Leisenring, Wendy; Balajee, S. Arunmozhi; Smith, Caitlin; Marr, Kieren A.

2004-01-01

Invasive pulmonary aspergillosis (IPA) is frequent and often fatal in hematopoietic stem cell transplant patients. Diagnosis requires microbiological or histopathologic demonstration of the organism in tissues; however, cultivation of Aspergillus species from respiratory secretions has low diagnostic sensitivity. Assays to detect Aspergillus antigen or DNA in bronchoalveolar lavage (BAL) fluid could facilitate earlier diagnosis, thereby guiding optimal therapy and obviating the need for additional costly and potentially morbid diagnostic evaluation. We evaluated the performance of a galactomannan enzyme immunoassay (GM EIA; Bio-Rad) by using a range of index cutoffs to define positivity and a quantitative PCR (qPCR) assay for the detection of Aspergillus species from BAL samples of patients with proven and probable IPA (case patients; n = 49) and without IPA (control patients; n = 50). The sensitivity of the GM EIA was 61% with an index cutoff of 1.0 and 76% with an index cutoff of 0.5; the corresponding specificities were 98 and 94%, respectively. The sensitivity and specificity of qPCR assay were 67 and 100%, respectively. The sensitivity with 22 culture-negative BAL specimens from patients with IPA was 41% for GM EIA with an index cutoff of 1.0, 59% for GM EIA with an index cutoff of 0.5, and 36% for qPCR assay. GM EIA indices and DNA quantities corresponded to BAL fungal burdens, with culture-positive samples having larger amounts of antigen and DNA compared to culture-negative samples. GM EIA and qPCR assay add to the sensitivity of BAL for diagnosing IPA in high-risk patients, with excellent specificity. Adjunctive use of these tests may reduce dependence on invasive diagnostic procedures. PMID:15583275

Real-time PCR (qPCR) primer design using free online software.

Science.gov (United States)

Thornton, Brenda; Basu, Chhandak

2011-01-01

Real-time PCR (quantitative PCR or qPCR) has become the preferred method for validating results obtained from assays which measure gene expression profiles. The process uses reverse transcription polymerase chain reaction (RT-PCR), coupled with fluorescent chemistry, to measure variations in transcriptome levels between samples. The four most commonly used fluorescent chemistries are SYBR® Green dyes and TaqMan®, Molecular Beacon or Scorpion probes. SYBR® Green is very simple to use and cost efficient. As SYBR® Green dye binds to any double-stranded DNA product, its success depends greatly on proper primer design. Many types of online primer design software are available, which can be used free of charge to design desirable SYBR® Green-based qPCR primers. This laboratory exercise is intended for those who have a fundamental background in PCR. It addresses the basic fluorescent chemistries of real-time PCR, the basic rules and pitfalls of primer design, and provides a step-by-step protocol for designing SYBR® Green-based primers with free, online software. Copyright © 2010 Wiley Periodicals, Inc.

Spectrometric microbiological analyzer

Science.gov (United States)

Schlager, Kenneth J.; Meissner, Ken E.

1996-04-01

Currently, there are four general approaches to microbiological analysis, i.e., the detection, identification and quantification of micro-organisms: (1) Traditional culturing and staining procedures, metabolic fermentations and visual morphological characteristics; (2) Immunological approaches employing microbe-specific antibodies; (3) Biotechnical techniques employing DNA probes and related genetic engineering methods; and (4) Physical measurement techniques based on the biophysical properties of micro-organisms. This paper describes an instrumentation development in the fourth of the above categories, physical measurement, that uses a combination of fluorometric and light scatter spectra to detect and identify micro-organisms at the species level. A major advantage of this approach is the rapid turnaround possible in medical diagnostic or water testing applications. Fluorometric spectra serve to define the biochemical characteristics of the microbe, and light scatter spectra the size and shape morphology. Together, the two spectra define a 'fingerprint' for each species of microbe for detection, identification and quantification purposes. A prototype instrument has been developed and tested under NASA sponsorship based on fluorometric spectra alone. This instrument demonstrated identification and quantification capabilities at the species level. The paper reports on test results using this instrument, and the benefits of employing a combination of fluorometric and light scatter spectra.

Accurate Detection of Methicillin-Resistant Staphylococcus aureus in Mixtures by Use of Single-Bacterium Duplex Droplet Digital PCR.

Science.gov (United States)

Luo, Jun; Li, Junhua; Yang, Hang; Yu, Junping; Wei, Hongping

2017-10-01

Accurate and rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) is needed to screen MRSA carriers and improve treatment. The current widely used duplex PCR methods are not able to differentiate MRSA from coexisting methicillin-susceptible S. aureus (MSSA) or other methicillin-resistant staphylococci. In this study, we aimed to develop a direct method for accurate and rapid detection of MRSA in clinical samples from open environments, such as nasal swabs. The new molecular assay is based on detecting the cooccurrence of nuc and mecA markers in a single bacterial cell by utilizing droplet digital PCR (ddPCR) with the chimeric lysin ClyH for cell lysis. The method consists of (i) dispersion of an intact single bacterium into nanoliter droplets, (ii) temperature-controlled release of genomic DNA (gDNA) by ClyH at 37°C, and (iii) amplification and detection of the markers ( nuc and mecA ) using standard TaqMan chemistries with ddPCR. Results were analyzed based on MRSA index ratios used for indicating the presence of the duplex-positive markers in droplets. The method was able to achieve an absolute limit of detection (LOD) of 2,900 CFU/ml for MRSA in nasal swabs spiked with excess amounts of Escherichia coli , MSSA, and other mecA -positive bacteria within 4 h. Initial testing of 104 nasal swabs showed that the method had 100% agreement with the standard culture method, while the normal duplex qPCR method had only about 87.5% agreement. The single-bacterium duplex ddPCR assay is rapid and powerful for more accurate detection of MRSA directly from clinical specimens. Copyright © 2017 American Society for Microbiology.

Identification of Burkholderia spp. in the Clinical Microbiology Laboratory: Comparison of Conventional and Molecular Methods

Science.gov (United States)

van Pelt, Cindy; Verduin, Cees M.; Goessens, Wil H. F.; Vos, Margreet C.; Tümmler, Burkhard; Segonds, Christine; Reubsaet, Frans; Verbrugh, Henri; van Belkum, Alex

1999-01-01

Cystic fibrosis (CF) predisposes patients to bacterial colonization and infection of the lower airways. Several species belonging to the genus Burkholderia are potential CF-related pathogens, but microbiological identification may be complicated. This situation is not in the least due to the poorly defined taxonomic status of these bacteria, and further validation of the available diagnostic assays is required. A total of 114 geographically diverse bacterial isolates, previously identified in reference laboratories as Burkholderia cepacia (n = 51), B. gladioli (n = 14), Ralstonia pickettii (n = 6), B. multivorans (n = 2), Stenotrophomonas maltophilia (n = 3), and Pseudomonas aeruginosa (n = 11), were collected from environmental, clinical, and reference sources. In addition, 27 clinical isolates putatively identified as Burkholderia spp. were recovered from the sputum of Dutch CF patients. All isolates were used to evaluate the accuracy of two selective growth media, four systems for biochemical identification (API 20NE, Vitek GNI, Vitek NFC, and MicroScan), and three different PCR-based assays. The PCR assays amplify different parts of the ribosomal DNA operon, either alone or in combination with cleavage by various restriction enzymes (PCR-restriction fragment length polymorphism [RFLP] analysis). The best system for the biochemical identification of B. cepacia appeared to be the API 20NE test. None of the biochemical assays successfully grouped the B. gladioli strains. The PCR-RFLP method appeared to be the optimal method for accurate nucleic acid-mediated identification of the different Burkholderia spp. With this method, B. gladioli was also reliably classified in a separate group. For the laboratory diagnosis of B. cepacia, we recommend parallel cultures on blood agar medium and selective agar plates. Further identification of colonies with a Burkholderia phenotype should be performed with the API 20NE test. For final confirmation of species identities, PCR

Microbiological implications of the food irradiation process

International Nuclear Information System (INIS)

Teufel, P.

1981-01-01

The Joint FAO/IAEA/WHO Expert Committee on the wholesomeness of irradiated food which met in 1976 concluded after a detailed and critical review of the available information, that the microbiological aspects of food irradiation were fully comparable to those of conventional processes used in modern food technology. Processing of food by irradiation may be considered from the microbiological point of view as separate procedures: high dose treatment (> 10 kGy), for sterilisation (radappertization) and low dose treatment (< 10 kGy) for pasteurisation (radicidation, radurization), (for definitions see p. 43), disinfestation, or inhibition of sprouting. No public health hazards related to micro-organisms arise from high dose irradiation because this process results in commercially sterile products. On the other hand, it is important to consider the possible microbiological hazards when food is irradiated with a low dose. The microbiological implications relate to the natural radiation resistance of bacteria, yeasts, fungi and viruses or to the mutagenic effects of ionising radiation in micro-organisms. Both areas of concern were reviewed in detail by Ingram and Ingram and Farkas. (orig.)

Lentinan Properties in Anticancer Therapy: A Review on the Last 12-Year Literature

Czech Academy of Sciences Publication Activity Database

Vannucci, Luca; Šíma, Petr; Větvička, V.; Křižan, Jiří

2017-01-01

Roč. 13, č. 1 (2017), s. 50-61 ISSN 1553-619X Institutional support: RVO:61388971 Keywords : Lentinan Properties * Anticancer Therapy Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology

Diagnostic virology laboratory within a microbiology setting.

Science.gov (United States)

Rubin, S J

1984-01-01

The virology section at St. Francis Hospital and Medical Center, Connecticut, is not a separate laboratory division but is a part of the microbiology division and is supervised by the same personnel who supervise bacteriology, mycology, mycobacteriology, and serology. Current volume is over 1,000 cultures yearly with 12 to 24 percent positive. Isolates are confirmed and typed by the Connecticut State Health Department Laboratory. Specimen distribution, percentage positive specimens, and distribution of viral isolates are similar to those reported from microbiology laboratories with separate virology laboratories directed by a full-time doctoral-level virologist. Our seven years' experience demonstrates that a microbiology laboratory without a full-time doctoral-level virologist can provide clinically useful virologic information.

Microbiological and therapeutic challenges in infectious spondylodiscitis

DEFF Research Database (Denmark)

Aagaard, Theis; Roed-Petersen, Casper; Dragsted, Casper

2013-01-01

The microbiological diagnosis of infectious spondylodiscitis is often difficult to establish and the disease requires prolonged antibiotic treatment. We analyzed the medical records of 100 patients admitted for infectious spondylodiscitis from 2006 to 2011 with an emphasis on (1) the diagnostic u...... utility of blood cultures and invasive biopsies in the microbiological diagnosis, (2) clinical features differentiating Staphylococcus aureus infections from those with other aetiologies, and (3) evaluation of the outcome of the antimicrobial therapy.......The microbiological diagnosis of infectious spondylodiscitis is often difficult to establish and the disease requires prolonged antibiotic treatment. We analyzed the medical records of 100 patients admitted for infectious spondylodiscitis from 2006 to 2011 with an emphasis on (1) the diagnostic...

Validation of the Pockit Dengue Virus Reagent Set for Rapid Detection of Dengue Virus in Human Serum on a Field-Deployable PCR System.

Science.gov (United States)

Tsai, Jih-Jin; Liu, Li-Teh; Lin, Ping-Chang; Tsai, Ching-Yi; Chou, Pin-Hsing; Tsai, Yun-Long; Chang, Hsiao-Fen Grace; Lee, Pei-Yu Alison

2018-05-01

Dengue virus (DENV) infection, a mosquito-borne disease, is a major public health problem in tropical countries. Point-of-care DENV detection with good sensitivity and specificity enables timely early diagnosis of DENV infection, facilitating effective disease management and control, particularly in regions of low resources. The Pockit dengue virus reagent set (GeneReach Biotech), a reverse transcription insulated isothermal PCR (RT-iiPCR), is available to detect all four serotypes of DENV on the field-deployable Pockit system, which is ready for on-site applications. In this study, analytical and clinical performances of the assay were evaluated. The index assay did not react with 14 non-DENV human viruses, indicating good specificity. Compared to the U.S. CDC DENV-1-4 real-time quantitative RT-PCR (qRT-PCR) assay, testing with serial dilutions of virus-spiked human sera demonstrated that the index assay had detection endpoints that were separately comparable with the 4 serotypes. Excellent reproducibility was observed among repeat tests done by six operators at three sites. In clinical performance, 195 clinical sera collected around Kaohsiung city in 2012 and 21 DENV-4-spiked sera were tested with the RT-iiPCR and qRT-PCR assays in parallel. The 121 (11 DENV-1, 78 DENV-2, 11 DENV-3, and 21 DENV-4) qRT-PCR-positive and 95 qRT-PCR-negative samples were all positive and negative by the RT-iiPCR reagent results, respectively, demonstrating high (100%) interrater agreement (95% confidence interval [CI 95% ], ∼98.81% to 100%; κ = 1). With analytical and clinical performance equivalent to those of the reference qRT-PCR assay, the index PCR assay on the field-deployable system can serve as a highly sensitive and specific on-site tool for DENV detection. Copyright © 2018 American Society for Microbiology.

European validation of a real-time PCR-based method for detection of Listeria monocytogenes in soft cheese.

Science.gov (United States)

Gianfranceschi, Monica Virginia; Rodriguez-Lazaro, David; Hernandez, Marta; González-García, Patricia; Comin, Damiano; Gattuso, Antonietta; Delibato, Elisabetta; Sonnessa, Michele; Pasquali, Frederique; Prencipe, Vincenza; Sreter-Lancz, Zuzsanna; Saiz-Abajo, María-José; Pérez-De-Juan, Javier; Butrón, Javier; Kozačinski, Lidija; Tomic, Danijela Horvatek; Zdolec, Nevijo; Johannessen, Gro S; Jakočiūnė, Džiuginta; Olsen, John Elmerdahl; De Santis, Paola; Lovari, Sarah; Bertasi, Barbara; Pavoni, Enrico; Paiusco, Antonella; De Cesare, Alessandra; Manfreda, Gerardo; De Medici, Dario

2014-08-01

The classical microbiological method for detection of Listeria monocytogenes requires around 7 days for final confirmation, and due to perishable nature of RTE food products, there is a clear need for an alternative methodology for detection of this pathogen. This study presents an international (at European level) ISO 16140-based validation trial of a non-proprietary real-time PCR-based methodology that can generate final results in the following day of the analysis. This methodology is based on an ISO compatible enrichment coupled to a bacterial DNA extraction and a consolidated real-time PCR assay. Twelve laboratories from six European countries participated in this trial, and soft cheese was selected as food model since it can represent a difficult matrix for the bacterial DNA extraction and real-time PCR amplification. The limit of detection observed was down to 10 CFU per 25 of sample, showing excellent concordance and accordance values between samples and laboratories (>75%). In addition, excellent values were obtained for relative accuracy, specificity and sensitivity (82.75%, 96.70% and 97.62%, respectively) when the results obtained for the real-time PCR-based methods were compared to those of the ISO 11290-1 standard method. An interesting observation was that the L. monocytogenes detection by the real-time PCR method was less affected in the presence of Listeria innocua in the contaminated samples, proving therefore to be more reliable than the reference method. The results of this international trial demonstrate that the evaluated real-time PCR-based method represents an excellent alterative to the ISO standard since it shows a higher performance as well as reduce the extent of the analytical process, and can be easily implemented routinely by the competent authorities and food industry laboratories. Copyright © 2014 Elsevier B.V. All rights reserved.

Geologic, geochemical, microbiologic, and hydrologic characterization at the In Situ Redox Manipulation Test Site

International Nuclear Information System (INIS)

Vermeul, V.R.; Teel, S.S.; Amonette, J.E.

1995-07-01

This report documents results from characterization activities at the In Situ Redox Manipulation (ISRM) Field Test Site which is located within the 100-HR-3 Operable Unit of the US Department of Energy's (DOE's) Hanford Site in Richland, Washington. Information obtained during hydrogeologic characterization of the site included sediment physical properties, geochemical properties, microbiologic population data, and aquifer hydraulic properties. The purpose of obtaining this information was to improve the conceptual understanding of the hydrogeology beneath the ISRM test site and provide detailed, site specific hydrogeologic parameter estimates. The resulting characterization data will be incorporated into a numerical model developed to simulate the physical and chemical processes associated with the field experiment and aid in experiment design and interpretation

PCR performance of a thermostable heterodimeric archaeal DNA polymerase

Science.gov (United States)

Killelea, Tom; Ralec, Céline; Bossé, Audrey; Henneke, Ghislaine

2014-01-01

DNA polymerases are versatile tools used in numerous important molecular biological core technologies like the ubiquitous polymerase chain reaction (PCR), cDNA cloning, genome sequencing, and nucleic acid based diagnostics. Taking into account the multiple DNA amplification techniques in use, different DNA polymerases must be optimized for each type of application. One of the current tendencies is to reengineer or to discover new DNA polymerases with increased performance and broadened substrate spectra. At present, there is a great demand for such enzymes in applications, e.g., forensics or paleogenomics. Current major limitations hinge on the inability of conventional PCR enzymes, such as Taq, to amplify degraded or low amounts of template DNA. Besides, a wide range of PCR inhibitors can also impede reactions of nucleic acid amplification. Here we looked at the PCR performances of the proof-reading D-type DNA polymerase from P. abyssi, Pab-polD. Fragments, 3 kilobases in length, were specifically PCR-amplified in its optimized reaction buffer. Pab-polD showed not only a greater resistance to high denaturation temperatures than Taq during cycling, but also a superior tolerance to the presence of potential inhibitors. Proficient proof-reading Pab-polD enzyme could also extend a primer containing up to two mismatches at the 3' primer termini. Overall, we found valuable biochemical properties in Pab-polD compared to the conventional Taq, which makes the enzyme ideally suited for cutting-edge PCR-applications. PMID:24847315

PCR performance of a thermostable heterodimeric archaeal DNA polymerase

Directory of Open Access Journals (Sweden)

Tom eKillelea

2014-05-01

Full Text Available DNA polymerases are versatile tools used in numerous important molecular biological core technologies like the ubiquitous polymerase chain reaction (PCR, cDNA cloning, genome sequencing and nucleic acid based diagnostics. Taking into account the multiple DNA amplification techniques in use, different DNA polymerases must be optimized for each type of application. One of the current tendencies is to reengineer or to discover new DNA polymerases with increased performance and broadened substrate spectra. At present, there is a great demand for such enzymes in applications, e.g., forensics or paleogenomics. Current major limitations hinge on the inability of conventional PCR enzymes, such as Taq, to amplify degraded or low amounts of template DNA. Besides, a wide range of PCR inhibitors can also impede reactions of nucleic acid amplification. Here we looked at the PCR performances of the proof-reading D-type DNA polymerase from P. abyssi, Pab-polD. Fragments, 3 kilobases in length, were specifically PCR-amplified in its optimized reaction buffer. Pab-polD showed not only a greater resistance to high denaturation temperatures than Taq during cycling, but also a superior tolerance to the presence of potential inhibitors. Proficient proof-reading Pab-polD enzyme could also extend a primer containing up to two mismatches at the 3’ primer termini. Overall, we found valuable biochemical properties in Pab-polD compared to the conventional Taq, which makes the enzyme ideally suited for cutting-edge PCR-applications.

A molecular-beacon-based asymmetric PCR assay for easy visualization of amplicons in the diagnosis of trichomoniasis.

Science.gov (United States)

Sonkar, Subash C; Sachdev, Divya; Mishra, Prashant K; Kumar, Anita; Mittal, Pratima; Saluja, Daman

2016-12-15

The currently available nucleic acid amplification tests (NAATs) for trichomoniasis are accurate, quick and confirmative with superior sensitivity than traditional culture-based microbiology assays. However, these assays are associated with problems of carry over contamination, false positive results, requirement of technical expertise for performance and detection of end product. Hence, a diagnostic assay with easy visualization of the amplified product will be profitable. An in-house, rapid, sensitive, specific molecular-beacon-based PCR assay, using primers against pfoB gene of Trichomonas vaginalis, was developed and evaluated using dry ectocervical swabs (n=392) from symptomatic females with vaginal discharge. Total DNA was isolated and used as template for the PCR assays. The performance and reproducibility of PCR assay was evaluated by composite reference standard (CRS). For easy visualization of the amplified product, molecular-beacon was designed and amplicons were visualized directly using fluorescent handheld dark reader or by Micro-Plate Reader. Molecular-beacons are single-stranded hairpin shaped nucleic acid probes composed of a stem, with fluorophore/quencher pair and a loop region complementary to the desired DNA. The beacon-based PCR assay designed in the present study is highly specific as confirmed by competition experiments and extremely sensitive with detection limit of 20fg of genomic DNA (3-4 pathogens). The minimum infrastructure requirement and ease to perform the assay makes this method highly useful for resource poor countries for better disease management. Copyright © 2016 Elsevier B.V. All rights reserved.

Mathematical analysis of the real time array PCR (RTA PCR) process

NARCIS (Netherlands)

Dijksman, Johan Frederik; Pierik, A.

2012-01-01

Real time array PCR (RTA PCR) is a recently developed biochemical technique that measures amplification curves (like with quantitative real time Polymerase Chain Reaction (qRT PCR)) of a multitude of different templates in a sample. It combines two different methods in order to profit from the

Evaluation of the Roche LightMix Gastro parasites multiplex PCR assay detecting Giardia duodenalis, Entamoeba histolytica, cryptosporidia, Dientamoeba fragilis, and Blastocystis hominis.

Science.gov (United States)

Friesen, J; Fuhrmann, J; Kietzmann, H; Tannich, E; Müller, M; Ignatius, R

2018-03-23

Multiplex PCR assays offer highly sensitive and specific tools for the detection of enteric pathogens. This prospective study aimed at comparing the novel Roche LightMix Modular Assay Gastro Parasites (LMAGP) detecting Giardia duodenalis, Entamoeba histolytica, Cryptosporidium spp., Blastocystishominis, and Dientamoebafragilis with routine laboratory procedures. Stool specimens (n = 1062 from 1009 patients) were consecutively examined by LMAGP, R-Biopharm Ridascreen enzyme immunoassays (EIAs) detecting G. duodenalis or E. histolytica/dispar, and microscopy of wet mounts. Discrepant results were analysed by in-house PCR. D. fragilis or B. hominis were detected by LMAGP in 131 (14.4%) and 179 (19.9%; 16 samples positive by microscopy; p PCR). G. duodenalis was detected by LMAGP, EIA, or microscopy in 20, 16, or 9 of 1039 stool samples, respectively; all four samples missed by EIA were confirmed by in-house PCR. In total, 938 stool samples were analysed for E. histolytica/dispar. Nine of ten EIA-positive samples were negative by LMAGP but positive by in-house PCR for E. dispar. One E. histolytica infection (positive by both LMAGP and in-house PCR) was missed by EIA and microscopy. Parasites only detected by microscopy included Enterobius vermicularis eggs (n = 3) and apathogenic amoebae (n = 27). The data call for routine use of multiplex PCR assays for the detection of enteric protozoan parasites in laboratory diagnostics. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Design and optimization of a novel reverse transcription linear-after-the-exponential PCR for the detection of foot-and-mouth disease virus.

Science.gov (United States)

Pierce, K E; Mistry, R; Reid, S M; Bharya, S; Dukes, J P; Hartshorn, C; King, D P; Wangh, L J

2010-07-01

A novel molecular assay for the detection of foot-and-mouth disease virus (FMDV) was developed using linear-after-the-exponential polymerase chain reaction (LATE-PCR). Pilot experiments using synthetic DNA targets demonstrated the ability of LATE-PCR to quantify initial target concentration through endpoint detection. A two-step protocol involving reverse transcription (RT) followed by LATE-PCR was then used to confirm the ability of the assay to detect FMDV RNA. Finally, RT and LATE-PCR were combined in a one-step duplex assay for co-amplification of an FMDV RNA segment and an internal control comprised of an Armored RNA. In that form, each of the excess primers in the reaction mixture hybridize to their respective RNA targets during a short pre-incubation, then generate cDNA strands during a 3-min RT step at 60°C, and the resulting cDNA is amplified by LATE-PCR without intervening sample processing. The RT-LATE-PCR assay generates fluorescent signals at endpoint that are proportional to the starting number of RNA targets and can detect a range of sequence variants using a single mismatch-tolerant probe. In addition to offering improvements over current laboratory-based molecular diagnostic assays for FMDV, this new assay is compatible with a novel portable ('point-of-care') device, the BioSeeq II, designed for the rapid diagnosis of FMD in the field. © 2009 The Authors. Journal compilation © 2009 The Society for Applied Microbiology.

CT an MR imaging of the paranasal sinuses in cystic fibrosis. Correlation with microbiological and histopathological results

International Nuclear Information System (INIS)

Eggesboe, H.B.; Stiris, M.

1999-01-01

Purpose: To compare CT and MR findings of the paranasal sinuses in patients with cystic fibrosis (CF) with microbiology and histopathology. Further, to compare microbiology from the maxillary sinuses, nasopharynx and sputum. Material and methods: CT and MR imaging of the paranasal sinuses were performed in 10 CF patients. Endoscopy and maxillary sinus aspirates were obtained (guided by the MR findings) and analyzed microbiologically and histologically. Samples from the nasopharynx and sputum were analyzed microbiologically. Results: CT and MR were equal in displaying the extent of soft tissue masses, which at CT were homogeneous, while MR showed heterogeneous signals. MR images also demonstrated circumscribed areas with signal void at the STIR sequence with corresponding high to intermediate signal at the T1-weighted sequence. P. aeruginosa was frequently cultured from these areas which we named the 'black hole sign'. Maxillary sinus cultures revealed the same bacteria as nasopharynx and sputum cultures combined. Conclusion: MR images were superior to CT in differentiating soft tissue masses in the paranasal sinuses in CF patients. Bacteria with potential for specialized iron uptake mechanisms were present in areas with signal void at the STIR sequence. Our hypothesis is that the MR 'black hole sign' can be explained by paramagnetic properties related to bacterial agents. (orig.)

Mycoplasma testing of cell substrates and biologics: Review of alternative non-microbiological techniques.

Science.gov (United States)

Volokhov, Dmitriy V; Graham, Laurie J; Brorson, Kurt A; Chizhikov, Vladimir E

2011-01-01

Mycoplasmas, particularly species of the genera Mycoplasma and Acholeplasma, are known to be occasional microbial contaminants of cell cultures that produce biologics. This presents a serious concern regarding the risk of mycoplasma contamination for research laboratories and commercial facilities developing and manufacturing cell-derived biological and biopharmaceutical products for therapeutic use. Potential undetected contamination of these products or process intermediates with mycoplasmas represents a potential safety risk for patients and a business risk for producers of biopharmaceuticals. To minimize these risks, monitoring for adventitious agents, such as viruses and mycoplasmas, is performed during the manufacture of biologics produced in cell culture substrates. The "gold standard" microbiological assay, currently recommended by the USP, EP, JP and the US FDA, for the mycoplasma testing of biologics, involves the culture of viable mycoplasmas in broth, agar plates and indicator cells. Although the procedure enables highly efficient mycoplasma detection in cell substrates and cell-derived products, the overall testing strategy is time consuming (a minimum of 28 days) and requires skilled interpretation of the results. The long time period required for these conventional assays does not permit their use for products with short shelf-lives or for timely 'go/no-go' decisions during routine in-process testing. PCR methodology has existed for decades, however PCR based and other alternative methods for mycoplasma detection have only recently been considered for application to biologics manufacture. The application of alternative nucleic acid-based, enzyme-based and/or recombinant cell-culture methods, particularly in combination with efficient sample preparation procedures, could provide advantages over conventional microbiological methods in terms of analytical throughput, simplicity, and turnaround time. However, a challenge to the application of alternative

Improved detection of Burkholderia pseudomallei from non-blood clinical specimens using enrichment culture and PCR: narrowing diagnostic gap in resource-constrained settings.

Science.gov (United States)

Tellapragada, Chaitanya; Shaw, Tushar; D'Souza, Annet; Eshwara, Vandana Kalwaje; Mukhopadhyay, Chiranjay

2017-07-01

To evaluate the diagnostic utility of enrichment culture and PCR for improved case detection rates of non-bacteraemic form of melioidosis in limited resource settings. Clinical specimens (n = 525) obtained from patients presenting at a tertiary care hospital of South India with clinical symptoms suggestive of community-acquired pneumonia, lower respiratory tract infections, superficial or internal abscesses, chronic skin ulcers and bone or joint infections were tested for the presence of Burkholderia pseudomallei using conventional culture (CC), enrichment culture (EC) and PCR. Sensitivity, specificity, positive and negative predictive values of CC and PCR were initially deduced using EC as the gold standard method. Further, diagnostic accuracies of all the three methods were analysed using Bayesian latent class modelling (BLCM). Detection rates of B. pseudomallei using CC, EC and PCR were 3.8%, 5.3% and 6%, respectively. Diagnostic sensitivities and specificities of CC and PCR were 71.4, 98.4% and 100 and 99.4%, respectively in comparison with EC as the gold standard test. With Bayesian latent class modelling, EC and PCR demonstrated sensitivities of 98.7 and 99.3%, respectively, while CC showed a sensitivity of 70.3% for detection of B. pseudomallei. An increase of 1.6% (95% CI: 1.08-4.32%) in the case detection rate of melioidosis was observed in the study population when EC and/or PCR were used in adjunct to the conventional culture technique. Our study findings underscore the diagnostic superiority of enrichment culture and/or PCR over conventional microbiological culture for improved case detection of melioidosis from non-blood clinical specimens. © 2017 John Wiley & Sons Ltd.

Development of simple and rapid PCR-fingerprinting methods for Vibrio cholerae on the basis of genetic diversity of the superintegron.

Science.gov (United States)

Chowdhury, N; Asakura, M; Neogi, S B; Hinenoya, A; Haldar, S; Ramamurthy, T; Sarkar, B L; Faruque, S M; Yamasaki, S

2010-07-01

To develop simple and rapid PCR-fingerprinting methods for Vibrio cholerae O1 (El Tor and classical biotypes) and O139 serogroup strains which cause major cholera epidemics, on the basis of the diversity of superintegron (SI) carried by these strains. PCR-restriction fragment length polymorphism (PCR-RFLP) assay was developed targeting region between integrase gene in the SI and its nearby ORF, followed by BglI digestion. Besides, a V. cholerae repeat-amplified fragment length polymorphism (VCR-AFLP) assay was also developed. In the PCR-RFLP, 94 El Tor, 29 classical and 54 O139 strains produced nine, three and six different DNA fingerprints, respectively. On the other hand, VCR-AFLP distinguished these El Tor, classical and O139 strains into five, nine and two DNA fingerprints, respectively. Combining both assays the El Tor, classical and O139 strains could be differentiated into 11, 10 and seven different types, respectively. In a comparative study, pulsed-field gel electrophoresis (PFGE) showed similar differentiation for El Tor (11 types), but lower discrimination for O139 (two types) and classical strains (five types). The PCR assays based on SI diversity can be used as a useful typing tool for epidemiological studies of V. cholerae. This newly developed method is more discriminatory, simple, rapid and cost-effective in comparison with PFGE, and thus can be widely applicable. © 2010 The Authors. Journal compilation © 2010 The Society for Applied Microbiology.

104 evaluation of microbiological purity of some brands of ...

African Journals Online (AJOL)

DR. AMINU

Keywords: Microbiological purity, tetracycline, contaminants, bacterial load, fungal load, microbiological ... Just like food substances, pharmaceutical products .... Malaysia. Chlortetracycline a. Mar. 2005. Mar. 2008. Ghana b. Aug. 2005. Aug.

Microbiological findings of vulvovaginitis in prepubertal girls.

Science.gov (United States)

Bumbulienė, Žana; Venclavičiūtė, Karolina; Ramašauskaite, Diana; Arlauskiene, Audrone; Bumbul, Elžbieta; Drąsutiene, Gražina

2014-01-01

To compare vaginal culture results between prepubertal girls with and without vulvovaginitis, and obtain an overview of the most commonly encountered microbes. Prospective descriptive study. Outpatient clinic of Vilnius University Hospital Santariskiu Klinikos during September 2011-December 2012. 115 prepubertal girls with vulvovaginitis symptoms and additionally 20 age-matched asymptomatic girls. Each girl had a vaginal smear carried out using a sterile swab from the introitus or lower third of the vagina. All samples were referred to the microbiology laboratory where standard microbiological diagnostic procedures were performed. Positive microbiological findings were seen in all 115 (100%) symptomatic girls and in 12 (60%) control group girls (pvulvovaginitis and from 5 (25%) girls without vaginal inflammation (pvulvovaginitis. The main causative premenarchal vulvovaginitis agents are faecal in origin.

Diagnostic microbiology in veterinary dermatology : present and future

NARCIS (Netherlands)

Guardabassi, Luca; Damborg, Peter; Stamm, Ivonne; Kopp, Peter A; Broens, Els M; Toutain, Pierre-Louis

BACKGROUND: The microbiology laboratory can be perceived as a service provider rather than an integral part of the healthcare team. OBJECTIVES: The aim of this review is to discuss the current challenges of providing a state-of-the-art diagnostic veterinary microbiology service including the

Critical notes on microbiological risk assessment of food

NARCIS (Netherlands)

Reij, M.W.; Schothorst, van M.

2000-01-01

Although numerous papers on Microbiological Risk Assessment (MRA) of food products have been published, a number of issues related to it remain unresolved. This paper explains the role of Microbiological Risk Assessment in the context of Risk Analysis as outlined by Codex Alimentarius. It reviews

New Highly Sensitive Real-Time PCR Assay for HIV-2 Group A and Group B DNA Quantification.

Science.gov (United States)

Bertine, Mélanie; Gueudin, Marie; Mélard, Adeline; Damond, Florence; Descamps, Diane; Matheron, Sophie; Collin, Fidéline; Rouzioux, Christine; Plantier, Jean-Christophe; Avettand-Fenoel, Véronique

2017-09-01

HIV-2 infection is characterized by a very low replication rate in most cases and low progression. This necessitates an approach to patient monitoring that differs from that for HIV-1 infection. Here, a new highly specific and sensitive method for HIV-2 DNA quantification was developed. The new test is based on quantitative real-time PCR targeting the long terminal repeat (LTR) and gag regions and using an internal control. Analytical performance was determined in three laboratories, and clinical performance was determined on blood samples from 63 patients infected with HIV-2 group A ( n = 35) or group B ( n = 28). The specificity was 100%. The 95% limit of detection was three copies/PCR and the limit of quantification was six copies/PCR. The within-run coefficients of variation were between 1.03% at 3.78 log 10 copies/PCR and 27.02% at 0.78 log 10 copies/PCR. The between-run coefficient of variation was 5.10%. Both manual and automated nucleic acid extraction methods were validated. HIV-2 DNA loads were detectable in blood cells from all 63 patients. When HIV-2 DNA was quantifiable, median loads were significantly higher in antiretroviral-treated than in naive patients and were similar for groups A and B. HIV-2 DNA load was correlated with HIV-2 RNA load ( r = 0.68; 95% confidence interval [CI], 0.4 to 0.8; P < 0.0001). Our data show that this new assay is highly sensitive and quantifies the two main HIV-2 groups, making it useful for the diagnosis of HIV-2 infection and for pathogenesis studies on HIV-2 reservoirs. Copyright © 2017 American Society for Microbiology.

The Swiss Society of Microbiology: Small Bugs, Big Questions and Cool Answers.

Science.gov (United States)

Greub, Gilbert; Holliger, Christof; Sanglard, Dominique; Schrenzel, Jacques; Thiel, Volker; Viollier, Patrick

2016-12-21

The Swiss Society for Microbiology (SSM) represents around 700 scientists working in the fields of medical (human and veterinary), microbial biotechnology as well as fundamental, environmental, and food microbiology. Five sections: Clinical Microbiology, Environmental Microbiology, Mycology, Prokaryotic Biology, and Virology reflects the main interests of the membership.

Summary of research on microbiological processes

International Nuclear Information System (INIS)

Winters, A.L.

1992-09-01

Storage of thermal energy in aquifers has obvious benefits of saving energy and decreasing the consumption of fossil fuels. However, aquifer thermal energy storage (ATES), which involves groundwater aquifers as the storage medium for heat or chill, impinges on the environment. A literature review of pertinent microbiology publications (Hicks and Stewart, 1988) identified the potential for the interaction of ATES systems and microbiological processes to create a source of infectious diseases and the potential for damage to the environment. In addition, the review identified a potential for microbiological processes to develop conditions that would interfere with the operation of an ATES system. As a result of this research effort, investigators from Finland, Germany, Switzerland, and the United States have examined several ATES systems in operation and have observed that the ATES systems studied do not contribute to infectious disease transmission, do not adversely affect the environment, and do not contribute significantly to biofouling or biocorrosion

Summary of research on microbiological processes

Energy Technology Data Exchange (ETDEWEB)

Winters, A.L.

1992-09-01

Storage of thermal energy in aquifers has obvious benefits of saving energy and decreasing the consumption of fossil fuels. However, aquifer thermal energy storage (ATES), which involves groundwater aquifers as the storage medium for heat or chill, impinges on the environment. A literature review of pertinent microbiology publications (Hicks and Stewart, 1988) identified the potential for the interaction of ATES systems and microbiological processes to create a source of infectious diseases and the potential for damage to the environment. In addition, the review identified a potential for microbiological processes to develop conditions that would interfere with the operation of an ATES system. As a result of this research effort, investigators from Finland, Germany, Switzerland, and the United States have examined several ATES systems in operation and have observed that the ATES systems studied do not contribute to infectious disease transmission, do not adversely affect the environment, and do not contribute significantly to biofouling or biocorrosion.

SASqPCR: robust and rapid analysis of RT-qPCR data in SAS.

Directory of Open Access Journals (Sweden)

Daijun Ling

Full Text Available Reverse transcription quantitative real-time PCR (RT-qPCR is a key method for measurement of relative gene expression. Analysis of RT-qPCR data requires many iterative computations for data normalization and analytical optimization. Currently no computer program for RT-qPCR data analysis is suitable for analytical optimization and user-controllable customization based on data quality, experimental design as well as specific research aims. Here I introduce an all-in-one computer program, SASqPCR, for robust and rapid analysis of RT-qPCR data in SAS. This program has multiple macros for assessment of PCR efficiencies, validation of reference genes, optimization of data normalizers, normalization of confounding variations across samples, and statistical comparison of target gene expression in parallel samples. Users can simply change the macro variables to test various analytical strategies, optimize results and customize the analytical processes. In addition, it is highly automatic and functionally extendable. Thus users are the actual decision-makers controlling RT-qPCR data analyses. SASqPCR and its tutorial are freely available at http://code.google.com/p/sasqpcr/downloads/list.

[Current panorama of the teaching of microbiology and parasitology in Spain].

Science.gov (United States)

Cantón, Rafael; Sánchez-Romero, María Isabel; Gómez-Mampaso, Enrique

2010-10-01

The training program of residents in microbiology and parasitology in Spain includes clinical skills, ranging from the diagnostic approach to the patient and adequate sample collection for diagnosis of infectious diseases to antimicrobial therapy and infection control measures. Training also includes new challenges in clinical microbiology that ensure residents' participation in infection control programs of health-care associated infections, training in the resolution of public health problems, and application of new molecular microbiology methods. Specialization in clinical microbiology may be undertaken by graduates in Medicine, Biology, Biochemistry and Chemistry. The training is performed in accredited microbiology laboratories at different hospitals (n = 61) across the country through 4-year residency programs. In the last few years, there has been a major imbalance between the number of intended residents (0.17 per 100,000 inhabitants) and those graduating as specialists in clinical microbiology (0.13 per 100,000 inhabitants), with wide variations across the country. The current tendency in Europe is to strengthen the role of clinical microbiologists as key figures in the diagnosis of infectious diseases and in public health microbiology. Training programs have been hampered by the practice of sending samples for microbiological tests to external, centralized multipurpose laboratories with few clinical microbiologists and without a core curriculum. Essential elements in the training of specialists in clinical microbiology are a close relationship between the laboratory and the clinical center and collaboration with other specialists. Copyright © 2010 Elsevier España S.L. All rights reserved.

Learning through Teaching: A Microbiology Service-Learning Experience

Directory of Open Access Journals (Sweden)

Ginny Webb

2015-11-01

Full Text Available Service learning is defined as a strategy in which students apply what they have learned in the classroom to a community service project. Many educators would agree that students often learn best through teaching others. This premise was the motivation for a new service-learning project in which undergraduate microbiology students developed and taught hands-on microbiology lessons to local elementary school children. The lessons included teaching basic information about microbes, disease transmission, antibiotics, vaccines, and methods of disease prevention. This service-learning project benefitted the college students by enforcing their knowledge of microbiology and provided them an opportunity to reach out to children within their community. This project also benefitted the local schools by teaching the younger students about microbes, infections, and handwashing. In this paper, I discuss the development and implementation of this new microbiology service-learning project, as well as the observed impact it had on everyone involved.

Spatiotemporal Dynamics of Vibrio cholerae in Turbid Alkaline Lakes as Determined by Quantitative PCR.

Science.gov (United States)

Bliem, Rupert; Reischer, Georg; Linke, Rita; Farnleitner, Andreas; Kirschner, Alexander

2018-06-01

lakes with a challenging water matrix. Several qPCR protocols for V. cholerae detection have been developed in the laboratory, but comprehensive studies on the application to environmental samples are extremely scarce. In our study, we demonstrate that our developed qPCR approach is a valuable tool but that there is a need for improvement in DNA recovery for complex water matrices. Furthermore, we found that nontoxigenic V. cholerae is present in very high numbers in the investigated ecosystems, while toxigenic V. cholerae is apparently absent. Such information is of importance for public health. Copyright © 2018 American Society for Microbiology.

New Egyptian Journal of Microbiology: About this journal

African Journals Online (AJOL)

New Egyptian Journal of Microbiology: About this journal. Journal Home > New Egyptian Journal of Microbiology: About this journal. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ...

Evaluation of a multiplex real-time PCR method for detecting shiga toxin-producing Escherichia coli in beef and comparison to the U.S. Department of Agriculture Food Safety and Inspection Service Microbiology laboratory guidebook method.

Science.gov (United States)

Fratamico, Pina M; Wasilenko, Jamie L; Garman, Bradley; Demarco, Daniel R; Varkey, Stephen; Jensen, Mark; Rhoden, Kyle; Tice, George

2014-02-01

The "top-six" non-O157 Shiga toxin-producing Escherichia coli (STEC) serogroups (O26, O45, O103, O111, O121, and O145) most frequently associated with outbreaks and cases of foodborne illnesses have been declared as adulterants in beef by the U.S. Department of Agriculture Food Safety and Inspection Service (FSIS). Regulatory testing in beef began in June 2012. The purpose of this study was to evaluate the DuPont BAX System method for detecting these top six STEC strains and strains of E. coli O157:H7. For STEC, the BAX System real-time STEC suite was evaluated, including a screening assay for the stx and eae virulence genes and two panel assays to identify the target serogroups: panel 1 detects O26, O111, and O121, and panel 2 detects O45, O103, O145. For E. coli O157:H7, the BAX System real-time PCR assay for this specific serotype was used. Sensitivity of each assay for the PCR targets was ≥1.23 × 10(3) CFU/ml in pure culture. Each assay was 100% inclusive for the strains tested (20 to 50 per assay), and no cross-reactivity with closely related strains was observed in any of the assays. The performance of the BAX System methods was compared with that of the FSIS Microbiology Laboratory Guidebook (MLG) methods for detection of the top six STEC and E. coli O157:H7 strains in ground beef and beef trim. Generally, results of the BAX System method were similar to those of the MLG methods for detecting non-O157 STEC and E. coli O157:H7. Reducing or eliminating novobiocin in modified tryptic soy broth (mTSB) may improve the detection of STEC O111 strains; one beef trim sample inoculated with STEC O111 produced a negative result when enriched in mTSB with 8 mg/liter novobiocin but was positive when enriched in mTSB without novobiocin. The results of this study indicate the feasibility of deploying a panel of real-time PCR assay configurations for the detection and monitoring of the top six STEC and E. coli O157:H7 strains in beef. The approach could easily be adapted

One-stop polymerase chain reaction (PCR): An improved PCR ...

African Journals Online (AJOL)

Yomi

2011-12-21

Dec 21, 2011 ... membrane filtration was carried out with a commercial PCR product purification kit (Generay, Shanghai), according to the manufacture's instruction. In brief, 50 µl PCR product was mixed thoroughly with binding buffer, and the resultant mixture was loaded directly onto a silica membrane Gelclean column.

Determination of some chemical and microbiological characteristics of Kaymak

Directory of Open Access Journals (Sweden)

Ökten, Sevtap

2006-12-01

Full Text Available Kaymak is a kind of concentrated cream, which is traditionally manufactured from buffalo or cow’s milk in Turkey. It is generally consumed with honey at breakfast and some traditional Turkish desserts. The aim of this study was to determine some chemical and microbiological properties of kaymak. The samples were obtained from different dairy plants producing kaymak from cow’s milk and local markets located in Zmir. They were examined for total solids and fat contents, acidity, pH and peroxide values, as well as counts of coliform bacteria, E. coli, yeast and moulds, and Staphylococci. Chemical characteristics of the samples were generally favorable for Turkish Food Codex. However, microbiological properties of some samples were very poor. Careful considerations should be given by the kaymak industry during manufacturing and storage of the product.Kaymak es una clase de crema concentrada, que se fabrica tradicionalmente de la leche del búfalo o de la vaca en Turquía. Se consume generalmente con la miel en el desayuno y en algunos postres turcos tradicionales. El objetivo de este estudio fue determinar algunas características químicas y microbiológicas del kaymak. Las muestras fueron obtenidas de diversas instalaciones lecheras productoras de kaymak de leche de vaca y de mercados locales situados en Zmir. Se analizó el contenido en sólidos totales y grasas, acidez, pH y valores de peróxido, además del conteo de tan bien como cuentas de las bacterias coliformes, E. coli, levadura y mohos, y estafilococos. Las características químicas de las muestras fueron generalmente aceptables para el Turkish Food Codex. Sin embargo, las características microbiológicas de algunas muestras fueron muy malas. La industria del kaymak debe ser extremadamente cuidadosa durante la fabricación y el almacenaje del producto.

Microbiological problems in radiosterilization

International Nuclear Information System (INIS)

Czerniawski, E.

1997-01-01

Microbiological problems connected with radiosterilization of medical materials, pharmaceuticals and cosmetics have been discussed in detail. Dose-response relationship for different bacteria has been shown. Recommended sterilization and postirradiation control procedures have been described. 24 refs, 6 figs, 5 tabs

Introduction to Clinical Microbiology for the General Dentist.

Science.gov (United States)

Rams, Thomas E; van Winkelhoff, Arie J

2017-04-01

Clinical oral microbiology may help dental professionals identify infecting pathogenic species and evaluate their in vitro antimicrobial susceptibility. Saliva, dental plaque biofilms, mucosal smears, abscess aspirates, and soft tissue biopsies are sources of microorganisms for laboratory testing. Microbial-based treatment end points may help clinicians better identify patients in need of additional or altered dental therapies before the onset of clinical treatment failure, and help improve patient oral health outcomes. Microbiological testing appears particularly helpful in periodontal disease treatment planning. Further research and technological advances are likely to increase the availability and clinical utility of microbiological analysis in modern dental practice. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of the gamma radiation on the chemical, rheological, baker and microbiological properties in wheat flour

International Nuclear Information System (INIS)

Agundez A, Z.; Fernandez R, M.V.; Arce C, M.E.; Cruz Z, E.; Chernov, V.; Barboza F, M.

2002-01-01

The gamma radiation has been used in several places of the World as a sterilization method, preservation and pasteurization of foodstuffs, effect which is achieved due to diminishing or elimination of the microorganisms, reaching every time more acceptance, moreover eliminates the uses of toxic and carcinogenic substances, of general use, but at the present, being in the process of being totally prohibited, due to the higher risk in the human health. In this work the related results with the effects of the gamma radiation are presented, coming from a 60 Co source, in commercial wheat flour exposed to a dose of 1.0 KGy. The used dose is that allowed according to the NOM-033-SSA1-1993 standard. It was determined that the chemical characteristics of humidity, protein and ashes were not affected by radiation. The rheological properties neither suffer severe effects as consequence of radiation; the pharynographic and alveographic parameters were lightly affected by the treatment. Significant changes were detected in the percentage of water absorption and in the tolerance index to mixing. However a diminish of 10% in the development time and an increase of 13% in the stability was observed, for the irradiated samples respect to the those samples not irradiated. In relation to the alveograph parameters it was only detected a diminish of 7% in the force parameter (w) without changes in the tenacity/blowing up index ratio (P/L). The fall number diminish 11% indicating a small diminution in viscosity. The bakering properties do not turn out modified by the irradiation treatment finding a specific weight of 4.6 and 4.5 (cm 3 /g) for the control and irradiated samples, respectively. In the mesophyll analysis it was found a diminish of 96% from the original charge in control samples, observing a diminution of 74 and 25% in yeasts and mushrooms respectively. Microbiologically it was determined absence of total coliforms bacteria and faecal coliforms in the control samples and of

Microbiological Spoilage of Cereal Products

Science.gov (United States)

Cook, Frederick K.; Johnson, Billie L.

A wide range of cereal products, including bakery items, refrigerated dough, fresh pasta products, dried cereal products, snack foods, and bakery mixes, are manufactured for food consumption. These products are subject to physical, chemical, and microbiological spoilage that affects the taste, aroma, leavening, appearance, and overall quality of the end consumer product. Microorganisms are ubiquitous in nature and have the potential for causing food spoilage and foodborne disease. However, compared to other categories of food products, bakery products rarely cause food poisoning. The heat that is applied during baking or frying usually eliminates pathogenic and spoilage microorganisms, and low moisture contributes to product stability. Nevertheless, microbiological spoilage of these products occurs, resulting in substantial economic losses.

Microbiological treatment of radioactive wastes

International Nuclear Information System (INIS)

Francis, A.J.

1992-01-01

The ability of microorganisms which are ubiquitous throughout nature to bring about information of organic and inorganic compounds in radioactive wastes has been recognized. Unlike organic contaminants, metals cannot be destroyed, but must be either removed or converted to a stable form. Radionuclides and toxic metals in wastes may be present initially in soluble form or, after disposal may be converted to a soluble form by chemical or microbiological processes. The key microbiological reactions include (i) oxidation/reduction; (ii) change in pH and Eh which affects the valence state and solubility of the metal; (iii) production of sequestering agents; and (iv) bioaccumulation. All of these processes can mobilize or stabilize metals in the environment

Microbiological influences on fracture surfaces of intact mud-stone

International Nuclear Information System (INIS)

West, J.M.; Harrison, H.; Wragg, J.; Wagner, D.; Milodowski, A.E.; Turner, G.; Lacinska, A.; Holyoake, S.; Harrington, J.; Coombs, P.; Bateman, K.; Yoshikawa, H.; Sasaki, Y.; Aoki, K.

2012-01-01

Document available in extended abstract form only. It is well recognised that microbes live in a wide range of subsurface environments including potential geological repository host rocks; and their presence can have an impact on transport processes. Microbial activity in any environment is located on chemical or physical interfaces, usually within bio-films. Their impact on transport can be physical (e.g. altering porosity) and/or chemical (e.g. changing redox conditions or altering pH) often resulting in intracellular or extracellular mineral formation or degradation. Consequently, the significance of microbial activity on the transport properties of potential host rocks for geological repositories is now being investigated. This pilot study investigates changes in transport properties that are because of microbial activity in sedimentary mud-stone rock environments at the Japan Atomic Energy Agency (JAEA) Horonobe underground research laboratory (URL) in northern Japan. The geological setting of the URL is summarised elsewhere. Geo-microbiological assessments of ground waters, from boreholes, previously drilled at Horonobe, have revealed the presence of a diverse indigenous microbiological ecosystem. The impacts of the presence of these microbes on the performance of a high-level radioactive waste (HLW) repository, using geo-microbiological data from Horonobe, has shown that denitrifying bacteria is likely to be the group of organisms with the greatest activity. Consequently, the impact of this group of organisms, specifically Pseudomonas denitrificans, on Horonobe rock transport properties, is the focus of this study. In brief, two experiments, one biotic and a 'control', were carried out using a flow-through column operated at a constant rate of fluid flow and under pressurised conditions. Changes in biological and chemical parameters were monitored throughout the experiment together with changes in confining pressure and temperature. The experiments were

The microbiology of Ethiopian foods and beverages: A review ...

African Journals Online (AJOL)

The microbiology of Ethiopian foods and beverages: A review. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... The topic on milk and dairy products deals with the livestock resource of the country with respect to the microbiological ...

Prevalence of periodontopathogenic bacteria in patients suffering from periodontitis using culture and PCR methods

Directory of Open Access Journals (Sweden)

Amir Aliramezani

2012-01-01

Full Text Available Background and Aims: Periodontitis is one of the most common oral diseases with the various incidence rates in different populations. A number of bacteria are considered as the major etiologic agents of periodontitis. The aim of the present study was to determine the prevalence of periodontopathogen bacteria in patients using both PCR and culture techniques.Materials and Methods: In this study, one-hundred patients (including 62 females and 38 males with an average age of 49±11.5 years with adult periodontitis referred to periodontics department of School of Dentistry/Tehran University of Medical Sciences were investigated. The samples were taken and sent immediately to the laboratory for culture and molecular evaluation. The PCR was performed using specific primers and the statistical analysis of data was performed using SPSS statistic software and McNemar test.Results: The results demonstrated that the total detection rate in culture method was 64%. The rate of Aggregatibacter actinomycetemcomitans (Aa was 28% which was significantly higher than that of Porphyromonas gingivalis (Pg (6% and Prevotella intermedia (Pi (3%. 27% of cases showed mixed bacterial growth. 65% of patients were positive using molecular method. The rate of Aa (30% was significantly higher than that of Pg (7% and Pi (5%. The mixed PCR positive rate containing of Aa, Pg and Pi was (23%.Conclusion: In this study, it was found that most of the bacteria isolated using culture and molecular methods were Aa, Pg and Pi, respectively. Although the detection frequencies of both techniques were similar, the specificity, sensitivity and bacterial detection speed of the PCR technique is obviously higher. Therefore, the use of molecular techniques is strongly recommended. However, both techniques seem to be suitable for microbiological diagnostics.

Comparison between digital PCR and real-time PCR in detection of Salmonella typhimurium in milk.

Science.gov (United States)

Wang, Meng; Yang, Junjie; Gai, Zhongtao; Huo, Shengnan; Zhu, Jianhua; Li, Jun; Wang, Ranran; Xing, Sheng; Shi, Guosheng; Shi, Feng; Zhang, Lei

2018-02-02

As a kind of zero-tolerance foodborne pathogens, Salmonella typhimurium poses a great threat to quality of food products and public health. Hence, rapid and efficient approaches to identify Salmonella typhimurium are urgently needed. Combined with PCR and fluorescence technique, real-time PCR (qPCR) and digital PCR (ddPCR) are regarded as suitable tools for detecting foodborne pathogens. To compare the effect between qPCR and ddPCR in detecting Salmonella typhimurium, a series of nucleic acid, pure strain culture and spiking milk samples were applied and the resistance to inhibitors referred in this article as well. Compared with qPCR, ddPCR exhibited more sensitive (10 -4 ng/μl or 10 2 cfu/ml) and less pre-culturing time (saving 2h). Moreover, ddPCR had stronger resistance to inhibitors than qPCR, yet absolute quantification hardly performed when target's concentration over 1ng/μl or 10 6 cfu/ml. This study provides an alternative strategy in detecting foodborne Salmonella typhimurium. Copyright © 2018 Elsevier B.V. All rights reserved.

The Effect of Having at Least One Previous Course in Microbiology upon the Test Scores of Students in a Veterinary Microbiologic Curriculum

Science.gov (United States)

Brown, John; And Others

1977-01-01

A comparative analysis of two groups of students indicated that unless individuals had special reasons for taking courses in microbiology before entering the College of Veterinary Medicine, these courses would be of no special benefit in the one-year microbiologic sequence. (LBH)

Effect of herbicides on microbiological properties of soil

Directory of Open Access Journals (Sweden)

Milošević Nada A.

2002-01-01

Full Text Available Microorganisms decompose herbicides and they may serve as bioindicators of soil changes following herbicide application. Certain microbial species may be used as bioherbicides. This study has shown that Azotobacter is most sensitive to herbicide application; it is, therefore, a reliable indicator of the biological value of soil. The numbers of this group of nitrogen-fixing bacteria decrease considerably in the period of 7-14 days after herbicide application. Simultaneously, the numbers of Actinomycetes and less so of fungi increase, indicating that these microorganisms use herbicides as sources of biogenous elements. Rate of herbicidal decomposition depends on the properties of the preparation applied herbicide dose as well as on the physical and chemical soil properties, soil moisture and temperature, ground cover, agrotechnical measures applied and the resident microbial population.

Microbiological aspects of vulvovaginitis in prepubertal girls.

Science.gov (United States)

Ranđelović, Gordana; Mladenović, Vesna; Ristić, Ljiljana; Otašević, Suzana; Branković, Sofija; Mladenović-Antić, Snežana; Bogdanović, Milena; Bogdanović, Dragan

2012-08-01

This study aimed to establish the vaginal introitus microbial flora in girls with and without symptoms of vulvovaginitis, and to present the distribution of isolated microorganisms by age groups in girls with vulvovaginitis. We enrolled 500 girls with vulvovaginitis symptoms, aged 2-12 years, referred by their pediatricians for microbiological examination of the vaginal introitus swabs, and 30 age-matched asymptomatic girls. Similar microbial flora was isolated in both groups, but the symptomatic girls had significantly more common positive microbiological findings compared to controls (p vulvovaginitis symptoms. The microbial ecosystem in girls with clinical signs of vulvovaginitis is complex and variable, and the presence of a microorganism does not necessarily imply that it is the cause of infection. The diagnosis of vulvovaginitis in prepubertal girls requires a complex and comprehensive approach, and microbiological findings should be interpreted in the context of clinical findings.

An Overview of Microbiology Research in Japan, with Notes on Medical History, Education and Health Care.

Science.gov (United States)

1981-07-01

the electron microscope to Japan, and discovery of vitamin B-decomposing bacteria (R. Kimura ). The Department of Microbiology recently underwent...the aid of monoclonal antibodies which have neutralizing activity. 22 Dr. Kimura is investigating the properties of Vibrio haemolyticus toxins, another...immunogenicity of the liposomes is the membrane fluidity, which can be regulated by modulating cholesterol content. Assistant Professor Hisashi Narimatsu

Microbiological risk assessment and public health

International Nuclear Information System (INIS)

Roger Skinner

1992-01-01

Despite the advances made in risk assessment i the past twenty years, in areas as diverse as toxicology and offshore engineering, the risk assessment approach has made little impact on those addressing the microbiological aspects of public health. In this paper the advances which have been made are discussed and the difficulties preventing the wider application of microbiological risk assessment (MRA) to public health are considered. The term microbiological risk is used here to mean the probability of contracting a disease caused by a microorganism. I intend to demonstrate that the dynamic nature of microorganisms and the unique nature of the relationship between a pathogen (a microorganism which causes disease) and its host create special challenges for those involved in MRA. Although these problems are difficult they are not intractable. Indeed in some cases partial solutions have already been found and applied. It is hoped that this paper will help stimulate further thought and consideration in a variety of disciplines so that these challenges can be met, thereby allowing MRA to fulfil its potential

Microbiological risk assessment and public health

Energy Technology Data Exchange (ETDEWEB)

Skinner, Roger

1992-07-01

Despite the advances made in risk assessment i the past twenty years, in areas as diverse as toxicology and offshore engineering, the risk assessment approach has made little impact on those addressing the microbiological aspects of public health. In this paper the advances which have been made are discussed and the difficulties preventing the wider application of microbiological risk assessment (MRA) to public health are considered. The term microbiological risk is used here to mean the probability of contracting a disease caused by a microorganism. I intend to demonstrate that the dynamic nature of microorganisms and the unique nature of the relationship between a pathogen (a microorganism which causes disease) and its host create special challenges for those involved in MRA. Although these problems are difficult they are not intractable. Indeed in some cases partial solutions have already been found and applied. It is hoped that this paper will help stimulate further thought and consideration in a variety of disciplines so that these challenges can be met, thereby allowing MRA to fulfil its potential.

Quantitative (real-time) PCR

International Nuclear Information System (INIS)

Denman, S.E.; McSweeney, C.S.

2005-01-01

Many nucleic acid-based probe and PCR assays have been developed for the detection tracking of specific microbes within the rumen ecosystem. Conventional PCR assays detect PCR products at the end stage of each PCR reaction, where exponential amplification is no longer being achieved. This approach can result in different end product (amplicon) quantities being generated. In contrast, using quantitative, or real-time PCR, quantification of the amplicon is performed not at the end of the reaction, but rather during exponential amplification, where theoretically each cycle will result in a doubling of product being created. For real-time PCR, the cycle at which fluorescence is deemed to be detectable above the background during the exponential phase is termed the cycle threshold (Ct). The Ct values obtained are then used for quantitation, which will be discussed later

The challenge of setting risk-based microbiological criteria for Listeria monocytogenes

DEFF Research Database (Denmark)

Andersen, Jens Kirk; Nørrung, Birgit

2011-01-01

After more than 20 years of work with discussing the setting of microbiological criteria for Listeria monocytogenes in foods, Codex Alimentarius on Food Hygiene has finalised a proposal that was recently adopted by the Codex Alimentarius Commission. The effort of developing procedures for making...... the microbiological criteria risk-based to the greatest extent possible has challenged scientists and managers during this long time period. Yet, the establishment of microbiological criteria for L. monocytogenes is still being discussed and several approaches are possible. Setting of microbiological criteria...

The Danish Microbiology Database (MiBa) 2010 to 2013.

Science.gov (United States)

Voldstedlund, M; Haarh, M; Mølbak, K

2014-01-09

The Danish Microbiology Database (MiBa) is a national database that receives copies of reports from all Danish departments of clinical microbiology. The database was launched in order to provide healthcare personnel with nationwide access to microbiology reports and to enable real-time surveillance of communicable diseases and microorganisms. The establishment and management of MiBa has been a collaborative process among stakeholders, and the present paper summarises lessons learned from this nationwide endeavour which may be relevant to similar projects in the rapidly changing landscape of health informatics.

Detection of residues antibiotics in food using a microbiological method

International Nuclear Information System (INIS)

Ben Ali, Ahmed

2007-01-01

Antibiotics are effective therapeutic agents because of their property of selective bacterial toxicity which helps controlling infections. Animals, just like humans, can be treated with antibiotics. This use of antibiotics can lead to the development of resistance. Resistant strains may cause severe infections in humans and animals. In addition, antibiotic residues might represent a problem for human health. Our objective is to develop a microbiological method for the detection of antibiotic residues in poultry(muscle, liver,...). For this purpose, antibiotic sensitive bacteria and selective agar media were used. An inhibition growth zone surrounds each of the food samples containing antibiotic residues after a prescribed incubation time. (Author). 23 refs

Simulation and experimental validation of a SU-8 based PCR thermocycler chip with integrated heaters and temperature sensor

DEFF Research Database (Denmark)

El-Ali, Jamil; Perch-Nielsen, Ivan R.; Poulsen, Claus Riber

2004-01-01

We present a SU-8 based polymerase chain reaction (PCR) chip with integrated platinum thin film heaters and temperature sensor. The device is fabricated in SU-8 on a glass substrate. The use of SU-8 provides a simple microfabrication process for the PCR chamber, controllable surface properties......C/s, respectively, the performance of the chip is comparable with the best silicon micromachined PCR chips presented in the literature. The SU-8 chamber surface was found to be PCR compatible by amplification of yeast gene ribosomal protein S3 and Campylobacter gene cadF. The PCR compatibility of the chamber...

Evaluation of the Xpert Flu test and comparison with in-house real-time RT-PCR assays for detection of influenza virus from 2008 to 2011 in Marseille, France.

Science.gov (United States)

Salez, N; Ninove, L; Thirion, L; Gazin, C; Zandotti, C; de Lamballerie, X; Charrel, R N

2012-04-01

Rapid documentation of respiratory specimens can have an impact on the management of patients and their relatives in terms of preventive and curative measures. We compared the results of the Xpert(®) Flu assay (Cepheid) with three real-time RT-PCR assays using 127 nasopharyngeal samples, of which 75 were positive for influenza A (with 52 identified as A/H1N1-2009) and 52 were positive for influenza B. The Xpert(®) Flu assay presented a quasi-absence of non-interpretable tests, and showed sensitivity and specificity of 100% and 100% for Flu A, 98.4% and 100% for A/H1N1-2009, and 80.7% and 100% for Flu B. © 2012 The Authors. Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases.

Evaluation of the efficiency of nested q-PCR in the detection of Mycobacterium tuberculosis complex directly from tuberculosis-suspected lesions in post-mortem macroscopic inspections of bovine carcasses slaughtered in the state of Mato Grosso, Brazil.

Science.gov (United States)

Carvalho, Ricardo César Tavares; Furlanetto, Leone Vinícius; Maruyama, Fernanda Harumy; Araújo, Cristina Pires de; Barros, Sílvia Letícia Bomfim; Ramos, Carlos Alberto do Nascimento; Dutra, Valéria; Araújo, Flábio Ribeiro de; Paschoalin, Vânia Margaret Flosi; Nakazato, Luciano; Figueiredo, Eduardo Eustáquio de Souza

2015-08-01

Bovine tuberculosis (BTB) is a zoonotic disease caused by Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex (MTC). The quick and specific detection of this species is of extreme importance, since BTB may cause economic impacts, in addition to presenting imminent risks to human health. In the present study a nested real-time PCR test (nested q-PCR) was used in post-mortem evaluations to assess cattle carcasses with BTB-suspected lesions. A total of 41,193 cattle slaughtered in slaughterhouses located in the state of Mato Grosso, were examined. Of the examined animals, 198 (0.48%) showed BTB-suspected lesions. M. bovis was isolated in 1.5% (3/198) of the samples. Multiplex-PCR detected MTC in 7% (14/198) of the samples. The nested q-PCR test detected MTC in 28% (56/198) of the BTB-suspected lesions, demonstrating higher efficiency when compared to the multiplex-PCR and conventional microbiology. Nested q-PCR can therefore be used as a complementary test in the national program for control and eradication of bovine tuberculosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

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.

Detection of Salmonella sp. from porcine origin: a comparison between a PCR method and standard microbiological techniques Detecção de Salmonella sp. em amostras de origem suína: comparação entre a técnica da Reação em Cadeia da Polimerase e o isolamento bacteriano convencional

Directory of Open Access Journals (Sweden)

Sandra Maria Ferraz Castagna

2005-12-01

Full Text Available The aim of this study was to compare a polymerase chain reaction (PCR method combined with selective enrichment in Rappaport-Vassiliadis broth (PCR-RVB with standard microbiological techniques (SMT for the generic detection of Salmonella in samples of porcine origin. Two hundred sixty eight field samples consisting of 42 sets of pooled porcine mandibular lymph nodes and tonsils, 44 samples of intestinal content, 38 pork sausage meat samples and 144 samples of feed collected from swine farms were submitted to the PCR-RVB and SMT protocols. Salmonella was detected in 54 samples using the PCR-RVB assay and in 42 samples by SMT, three of the SMT Salmonella-positive samples (one each of S. Derby, S. Panama and S. Typhimurium being Salmonella-negative by PCR-RVB. For the PCR-RVB method 15 Salmonella-positive samples were negative by SMT, a significant difference according to the Mac Nemar's chi-squared test (p=0.0153. Subsequent serological typing of the SMT isolates showed the following Salmonella serovars, the number of positive samples being given in parentheses: Typhimurium (12; Bredeney (10; Panama (5; Saint-paul (5; Minnesota (3; Mbandaka (2; Derby (1; Enteritidis (1; Orion (1 and Salmonella sp. (2. We concluded that, although the use of both PCR-RVB and SMT increased the number of positive samples, the PCR-RVB, due to its higher sensitivity and greater speed in giving results, can be implemented to detect Salmonella in samples of porcine origin.O objetivo desse estudo foi comparar um método de Reação em Cadeia da Polimerase (PCR combinado com enriquecimento seletivo em caldo Rappaport-Vassiliadis (PCR-RVB com as técnicas de isolamento bacteriano convencional (SMT para a detecção do gênero Salmonella em amostras de origem suína. Duzentas e sessenta e oito amostras de campo, compostas por: 42 "pools" de linfonodos mandibulares e tonsilas, 44 amostras de conteúdo intestinal, 38 amostras de massa de embutidos e 144 amostras de ra

COMPARISON OF 16S rRNA-PCR-RFLP, LipL32-PCR AND OmpL1-PCR METHODS IN THE DIAGNOSIS OF LEPTOSPIROSIS

Directory of Open Access Journals (Sweden)

Tülin GÜVEN GÖKMEN

Full Text Available SUMMARY Leptospirosis is still one of the most important health problems in developing countries located in humid tropical and subtropical regions. Human infections are generally caused by exposure to water, soil or food contaminated with the urine of infected wild and domestic animals such as rodents and dogs. The clinical course of leptospirosis is variable and may be difficult to distinguish from many other infectious diseases. The dark-field microscopy (DFM, serology and nucleic acid amplification techniques are used to diagnose leptospirosis, however, a distinctive standard reference method is still lacking. Therefore, in this study, we aimed to determine the presence of Leptospira spp., to differentiate the pathogenic L. interrogans and the non-pathogenic L. biflexa, and also to determine the sensitivity and specificity values of molecular methods as an alternative to conventional ones. A total of 133 serum samples, from 47 humans and 86 cattle were evaluated by two conventional tests: the Microagglutination Test (MAT and the DFM, as well as three molecular methods, the 16S rRNA-PCR followed by Restriction Fragment Lenght Polymorphism (RFLP of the amplification products 16S rRNA-PCR-RFLP, LipL32-PCR and OmpL1-PCR. In this study, for L. interrogans, the specificity and sensitivity rates of the 16S rRNA-PCR and the LipL32-PCR were considered similar (100% versus 98.25% and 100% versus 98.68%, respectively. The OmpL1-PCR was able to classify L. interrogans into two intergroups, but this PCR was less sensitive (87.01% than the other two PCR methods. The 16S rRNA-PCR-RFLP could detect L. biflexa DNA, but LipL32-PCR and OmpL1-PCR could not. The 16S rRNA-PCR-RFLP provided an early and accurate diagnosis and was able to distinguish pathogenic and non-pathogenic Leptospira species, hence it may be used as an alternative method to the conventional gold standard techniques for the rapid disgnosis of leptospirosis.

Impact of Helminth Infection on the Clinical and Microbiological Presentation of Chagas Diseases in Chronically Infected Patients.

Directory of Open Access Journals (Sweden)

Fernando Salvador

2016-04-01

Full Text Available Helminth infections are highly prevalent in tropical and subtropical countries, coexisting in Chagas disease endemic areas. Helminth infections in humans may modulate the host immune system, changing the Th1/Th2 polarization. This immunological disturbance could modify the immune response to other infections. The aim of this study is to evaluate the relationship between clinical, microbiological and epidemiological characteristics of Chagas disease patients, with the presence of helminth infection.A prospective observational study was conducted at Vall d'Hebron University Hospital (Barcelona, Spain. Inclusion criteria were: age over 18 years, diagnosis of Chagas disease, and not having received specific treatment for Chagas disease previously to the inclusion. The study protocol included Chagas disease assessment (cardiac and digestive evaluation, detection of T. cruzi DNA measured by PCR in peripheral blood, and helminth infection diagnosis (detection of IgG anti-Strongyloides stercoralis by ELISA, microscopic examination of stool samples from three different days, and specific faecal culture for S. stercoralis larvae.Overall, 65 patients were included, median age was 38 years, 75.4% were women and most of them came from Bolivia. Cardiac and digestive involvement was present in 18.5% and 27.7% of patients respectively. T. cruzi PCR was positive in 28 (43.1% patients. Helminth infection was diagnosed in 12 (18.5% patients. No differences were observed in clinical and epidemiological characteristics between patients with and without helminth infection. Nevertheless, the proportion of patients with positive T. cruzi PCR was higher among patients with helminth infection compared with patients without helminth infection (75% vs 35.8%, p = 0.021.We observed a high prevalence of S. stercoralis infection among chronic Chagas disease patients attended in our tropical medicine unit. Strongyloidiasis was associated with significantly higher proportion of

From the 'PCR' function to the 'PCR' profession; de la fonction 'PCR' au metier 'PCR'

Energy Technology Data Exchange (ETDEWEB)

Perrin, L. [CERAP, 91 - Gif sur Yvette (France)

2008-07-01

After having recalled the legal context concerning the appointment and training of a radiation protection expert (PCR for 'personne competente en radioprotection'), the author outlines that the PCR's role has notably evolved: his function is now of primary importance in the company and his activity does not correspond to the legal framework any longer. Moreover, with the application of a European directive, some small establishments possessing ionizing radiation sources are disadvantaged, and the PCR is now facing an increasing number of missions and tasks. The author gives a list of them and assesses a needed time of 146 days per year: this means PCRs cannot have an other activity within their company

Factors impacting on the microbiological quality and safety of ...

African Journals Online (AJOL)

hope&shola

2010-12-06

Dec 6, 2010 ... microbiological quality and safety of processed hake. Samples were collected along the processing line; the general microbiological quality (mesophylic and psychrotrophic aerobic plate counts), total. Vibrio species and common fish spoilage bacterial counts were performed. The results constantly showed ...

Effect of fortification of milk with omega-3 fatty acids, phytosterols and soluble fibre on the sensory, physicochemical and microbiological properties of milk.

Science.gov (United States)

Nagarajappa, Veena; Battula, Surendra Nath

2017-09-01

The effect of the addition of flaxseed oil (FO), phytosterols (PS) and polydextrose (PDX) on the physicochemical and sensory properties of milk was investigated, as they are known to impart health benefits. For incorporating PS, a hydrophobic substance, FO and milk fat (MF) as an oil source, an emulsifier (DATEM) and PDX solution as an aqueous medium were used for the preparation of emulsion. Three emulsion formulations A (8 g PS, 8 g FO, 20 g PDX, 6 g MF), B (10 g PS, 10 g FO, 20 g PDX, 4 g MF) and C (12 g PS, 12 g FO, 20 g PDX, 2 g MF) were prepared and added individually to milk at a level of 50 g kg -1 . Based on sensory evaluation, formulation B was selected for fortification of milk. The fortified milk kept well at refrigerated temperature for 1 week, and changes in sensory, physicochemical and microbiological properties were comparable to those of control milk. The level of fortificants did not decrease in the milk after 1 week of storage. An emulsion containing FO, PS and PDX could successfully serve as a potential delivery system for enhancing the nutritional and therapeutic potential of milk. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Commutability of food microbiology proficiency testing samples.

Science.gov (United States)

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

Quality control for diagnostic oral microbiology laboratories in European countries

Directory of Open Access Journals (Sweden)

Andrew J. Smith

2011-11-01

Full Text Available Participation in diagnostic microbiology internal and external quality control (QC processes is good laboratory practice and an essential component of a quality management system. However, no QC scheme for diagnostic oral microbiology existed until 2009 when the Clinical Oral Microbiology (COMB Network was created. At the European Oral Microbiology Workshop in 2008, 12 laboratories processing clinical oral microbiological samples were identified. All these were recruited to participate into the study and six laboratories from six European countries completed both the online survey and the first QC round. Three additional laboratories participated in the second round. Based on the survey, European oral microbiology laboratories process a significant (mean per laboratory 4,135 number of diagnostic samples from the oral cavity annually. A majority of the laboratories did not participate in any internal or external QC programme and nearly half of the laboratories did not have standard operating procedures for the tests they performed. In both QC rounds, there was a large variation in the results, interpretation and reporting of antibiotic susceptibility testing among the laboratories. In conclusion, the results of this study demonstrate the need for harmonisation of laboratory processing methods and interpretation of results for oral microbiology specimens. The QC rounds highlighted the value of external QC in evaluating the efficacy and safety of processes, materials and methods used in the laboratory. The use of standardised methods is also a prerequisite for multi-centre epidemiological studies that can provide important information on emerging microbes and trends in anti-microbial susceptibility for empirical prescribing in oro-facial infections.

Updated Cases for Medical Microbiology

Directory of Open Access Journals (Sweden)

Brinda Govindan

2015-08-01

Full Text Available Review of: Cases in Medical Microbiology and Infectious Diseases, 4th ed.; Peter H. Gilligan, Daniel S. Shapiro, and Melissa B. Miller; (2014. ASM Press, Washington, DC. 589 pages.

[Microbiological characteristics of selected liquid soaps for hands washing].

Science.gov (United States)

Tyski, Stefan; Bocian, Ewa; Zawistowska, Anna; Mrówka, Agnieszka; Kruszewska, Hanna; Grzybowska, Wanda; Zareba, Tomasz

2013-01-01

According to common belief, supported by the authority of the World Health Organization - WHO, the common (social) hand washing is the simplest, cheapest and the most effective way of reduction the hospital-acquired infections. For this purpose products of"liquid soaps", present in a large number on the market, are most often applied. Microbiological status (microbiological purity and antimicrobial activity) of"liquid soaps" available on the Polish market is not known, because relevant routinely studies have not been performed. Only the antibacterial and / or antifungal activity of certain formulations is sometimes assessed, especially when the manufacturer suggests the standardized application of the products for surgical or hygienic procedures. The aim of this study was to determine the microbiological quality, especially microbiological purity and antimicrobial activity of the selected hands washing products, presents on the Polish market. The 12 selected commercial products, available on the market in Poland, dedicated for hands washing were included into study. Microbiological purity test was carried out in accordance with the Polish Pharmacopoeia (FP) monograph (FP monograph numbers correspond to numbers of the European Pharmacopoeia monograph- Ph. Eur.) No 2.6.12 "Microbiological examination of non-sterile products: microbial enumaration tests", and the monograph of FP No. 2.6.13 "Microbiological examination of non-sterile products: test for specified microorganisms". The following physico-chemical properties of soaps were examined: the pH of the formulations was measured according to the monograph FP No. 2.2.3. "Potentiometric determination of pH", the density of products was assayed according to the monograph FPNo. 2.2.5. "Relative density" and determination the water activity was performed by monograph FP No 2.9.39 "Water-solid interactions: determination of sorption-desorption isotherms and of water activity". Next, antibacterial and antifungal

Quantitative Real-Time PCR using the Thermo Scientific Solaris qPCR Assay

Science.gov (United States)

Ogrean, Christy; Jackson, Ben; Covino, James

2010-01-01

The Solaris qPCR Gene Expression Assay is a novel type of primer/probe set, designed to simplify the qPCR process while maintaining the sensitivity and accuracy of the assay. These primer/probe sets are pre-designed to >98% of the human and mouse genomes and feature significant improvements from previously available technologies. These improvements were made possible by virtue of a novel design algorithm, developed by Thermo Scientific bioinformatics experts. Several convenient features have been incorporated into the Solaris qPCR Assay to streamline the process of performing quantitative real-time PCR. First, the protocol is similar to commonly employed alternatives, so the methods used during qPCR are likely to be familiar. Second, the master mix is blue, which makes setting the qPCR reactions easier to track. Third, the thermal cycling conditions are the same for all assays (genes), making it possible to run many samples at a time and reducing the potential for error. Finally, the probe and primer sequence information are provided, simplifying the publication process. Here, we demonstrate how to obtain the appropriate Solaris reagents using the GENEius product search feature found on the ordering web site (www.thermo.com/solaris) and how to use the Solaris reagents for performing qPCR using the standard curve method. PMID:20567213

Towards a Portuguese database of food microbiological occurrence

OpenAIRE

Viegas, Silvia; Machado, Claudia; Dantas, M.Ascenção; Oliveira, Luísa

2011-01-01

Aims: To expand the Portuguese Food Information Resource Programme (PortFIR) by building the Portuguese Food Microbiological Information Network (RPIMA) including users, stakeholders, food microbiological data producers that will provide data and information from research, monitoring, epidemiological investigation and disease surveillance. The integration of food data in a national database will improve foodborne risk management. Methods and results Potential members were identified and...

“Pick-up Lines”: A Fun Way to Facilitate Learning Microbiological Concepts

Directory of Open Access Journals (Sweden)

Thomas Edison E. dela Cruz

2014-05-01

Full Text Available Learning microbiology can be made fun by writing funny lines related to microbiology. Students were tasked to create their own pick-up lines and explain these based on their understanding of the basic concepts in microbiology.

Twenty-first-century medical microbiology services in the UK.

Science.gov (United States)

Duerden, Brian

2005-12-01

With infection once again a high priority for the UK National Health Service (NHS), the medical microbiology and infection-control services require increased technology resources and more multidisciplinary staff. Clinical care and health protection need a coordinated network of microbiology services working to consistent standards, provided locally by NHS Trusts and supported by the regional expertise and national reference laboratories of the new Health Protection Agency. Here, I outline my thoughts on the need for these new resources and the ways in which clinical microbiology services in the UK can best meet the demands of the twenty-first century.

MICROBIOLOGICAL CHARACTERISATION OF Haemophilus influenzae STRAINS ISOLATED FROM PATIENTS WITH INVASIVE AND RESPIRATORY DISEASES

Directory of Open Access Journals (Sweden)

Tomislav Kostyanev

2010-01-01

Full Text Available A total of 175 H. influenzae strains were collected between 1994 and 2009 from all aged patient groups. The strains were isolated from patients with invasive and community-acquired respiratory tract infections. All strains were identified according to standard microbiological methods. Serotyping was done by a coagglutination test and by molecular PCR capsular genotyping. Beta-lactamase production was determined by the chromogenic cephalosporin test with nitrocephin as substrate. Most of the isolated H. influenzae strains were from children under 5 years of age (57.7%. Overall, 61 strains belonged to serotype b (34.9% by the means of PCR capsular typing, 1 strain was type f, and 113 isolates (64.6% were non-typeable (non-encapsulated H. influenzae. Among the infants and children with meningitis or other invasive infections, aged 2 month to 5 years, all strains, except one, were serotype b. In respiratory tract infections (pneumonia, otitis media, sinusitis and people with chronic pulmonary diseases - exacerbations of COPD, bronchiectasis, cystic fibrosis the most common - 96.5% were non-typeable strains in both groups children and adults. Overall, the prevalence of beta-lactamase production was 19.4%. But, it was much higher for invasive strains from CSF isolates - 37.7%, 25% in blood samples, and 37.5% in otitis media causative strains. Beta-lactamase production was less frequent in respiratory tract isolates - in sputum 13.3% and in URT samples - 2.3%. The rate of beta-lactamase production in CSF isolates has not changed for the last 10 years.PCR capsular genotyping method has to be performed for all non-b-type strains. The implementation of Hib vaccine in our country will be accompanied by a reduction in invasive diseases caused by H. influenzae type b in children, but it is not useful in preventing infections caused by non-typeable H. influenzae strains.

ReadqPCR and NormqPCR: R packages for the reading, quality checking and normalisation of RT-qPCR quantification cycle (Cq data

Directory of Open Access Journals (Sweden)

Perkins James R

2012-07-01

Full Text Available Abstract Background Measuring gene transcription using real-time reverse transcription polymerase chain reaction (RT-qPCR technology is a mainstay of molecular biology. Technologies now exist to measure the abundance of many transcripts in parallel. The selection of the optimal reference gene for the normalisation of this data is a recurring problem, and several algorithms have been developed in order to solve it. So far nothing in R exists to unite these methods, together with other functions to read in and normalise the data using the chosen reference gene(s. Results We have developed two R/Bioconductor packages, ReadqPCR and NormqPCR, intended for a user with some experience with high-throughput data analysis using R, who wishes to use R to analyse RT-qPCR data. We illustrate their potential use in a workflow analysing a generic RT-qPCR experiment, and apply this to a real dataset. Packages are available from http://www.bioconductor.org/packages/release/bioc/html/ReadqPCR.htmland http://www.bioconductor.org/packages/release/bioc/html/NormqPCR.html Conclusions These packages increase the repetoire of RT-qPCR analysis tools available to the R user and allow them to (amongst other things read their data into R, hold it in an ExpressionSet compatible R object, choose appropriate reference genes, normalise the data and look for differential expression between samples.

A multiplex PCR assay for the detection and quantification of Sclerotinia sclerotiorum and Botrytis cinerea.

Science.gov (United States)

Reich, J D; Alexander, T W; Chatterton, S

2016-05-01

Traditional culture methods for identifying the plant fungal pathogens Sclerotinia sclerotiorum (Lib.) de Bary and Botrytis cinerea Pers.:Fr. are slow and laborious. The goal of this study was to develop a multiplex real-time PCR (qPCR) assay to detect and quantify DNA from S. sclerotiorum and B. cinerea. A primer set (SsIGS_5) for S. sclerotiorum was designed that targeted the intergenic spacer (IGS) regions of the ribosomal DNA. Addition of a probe to the assay increased its specificity: when the primer/probe set was tested against 21 fungal species (35 strains), amplification was detected from all S. sclerotiorum strains and no other species. For qPCR, the SsIGS_5 primer and probe set exhibited a linear range from 7·0 ng to 0·07 pg target DNA (R(2)  = 0·99). SsIGS_5 was then multiplexed with a previously published primer/probe set for B. cinerea to develop a high-throughput method for the detection and quantification of DNA from both pathogens. When multiplexed, the sensitivity and specificity of both assays were not different from individual qPCR reactions. The multiplex assay is currently being used to detect and quantify S. sclerotiorum and B. cinerea DNA from aerosol samples collected in commercial seed alfalfa fields. A primer and probe set for the quantification of Sclerotinia sclerotiorum DNA in a PCR assay was developed. The probe-based nature of this assay signifies an improvement over previous assays for this species by allowing multiplex reactions while maintaining high sensitivity. The primer/probe set was used in a multiplex real-time PCR assay for the quantification of S. sclerotiorum and Botrytis cinerea DNA, enabling rapid analysis of environmental samples. In crops susceptible to both pathogens, this multiplex assay can be used to quickly quantify the presence of each pathogen. © 2016 Her Majesty the Queen in Right of Canada © 2016 The Society for Applied Microbiology. Reproduced with the permission of the Office of the

Prescott’s Microbiology, Eighth Edition

OpenAIRE

Dobbins, Joanne J.

2010-01-01

Review of: Prescott’s Microbiology, Eighth Edition. Joanne M. Willey, Linda M. Sherwood, and Christopher J. Woolverton. 2011. McGraw-Hill Higher Education, NewYork, NY. 1070 pages. ISBN- 978-0-07-337526-7.

Microbiological Evaluation and Nutritional Quality of Ogi made from ...

African Journals Online (AJOL)

Microbiological evaluation and nutritional quality of ogi made from sorghum substituted with millet was carried out in this research work. A standard method was used for the proximate composition analysis and characterization of isolates was carried out by standard microbiological techniques. Protein content was found to ...

Microbiological and physico-chemical assessment of the quality of ...

African Journals Online (AJOL)

The domestic raw water sources in Nkonkobe and Gogogo were characterised by using both microbiological and standard physical methods to investigate the quality of the water at the sampling sites. For microbiological analysis, indicator bacteria namely, heterotrophic bacteria, total and faecal coliforms and for physical ...

Microbiological testing of Skylab foods.

Science.gov (United States)

Heidelbaugh, N. D.; Mcqueen, J. L.; Rowley, D. B.; Powers , E. M.; Bourland, C. T.

1973-01-01

Review of some of the unique food microbiology problems and problem-generating circumstances the Skylab manned space flight program involves. The situations these problems arise from include: extended storage times, variations in storage temperatures, no opportunity to resupply or change foods after launch of the Skylab Workshop, first use of frozen foods in space, first use of a food-warming device in weightlessness, relatively small size of production lots requiring statistically valid sampling plans, and use of food as an accurately controlled part in a set of sophisticated life science experiments. Consideration of all of these situations produced the need for definite microbiological tests and test limits. These tests are described along with the rationale for their selection. Reported test results show good compliance with the test limits.

THE ASSESSMENT OF MICROBIOLOGICAL INDOOR AIR QUALITY IN BAKERIES

Directory of Open Access Journals (Sweden)

Elżbieta Wołejko

2016-05-01

Full Text Available The aim of this study was to assess microbiological indoor air quality of selected bakeries located in the region of Podlasie. The microbiological studies were conducted in autumn in 2014 in three selected bakeries. Microbiological air counts were measured by impaction using an air sampler MAS-100 NT. The microbiological air studies, comprised the determination of the total number of psychrophilic and mesophilic bacteria, namely indicator bacteria such as: bacteria of the species Pseudomonas fluorescens, mannitol-positive and mannitol-negative Staphylococc, the total number of bacteria from the Enterobacteriaceae family and fungi found in atmospheric air. The results of the study of indoor air polluted with the analyzed groups of microorganisms differed depending on the type of test air and the location of the manufacturing plant. In the plants, the concentration of mesophilic bacteria and mannitol–positive and mannitol-negative Staphylococcus exceeded the limit values of unpolluted air, according to the Polish Standard recommendations.

External PCR, ASN's decision

International Nuclear Information System (INIS)

Anon.

2012-01-01

The French law imposes in some situations the presence of a person skilled in radiation protection (PCR). This article describes the cases when this person must belong to the staff of the enterprise or when this person may be sub-contracted. For instance in most nuclear facilities the PCR must be on the payroll, for enterprises dedicated to nuclear transport the PCR's job can be sub-contracted. A decision given by the ASN (French Nuclear Safety Authority) sets the minimal requests (in terms of training, job contract, activities) of the sub-contracted PCR. (A.C.)

PCR melting profile (PCR MP - a new tool for differentiation of Candida albicans strains

Directory of Open Access Journals (Sweden)

Nowak Magdalena

2009-11-01

Full Text Available Abstract Background We have previously reported the use of PCR Melting Profile (PCR MP technique based on using low denaturation temperatures during ligation mediated PCR (LM PCR for bacterial strain differentiation. The aim of the current study was to evaluate this method for intra-species differentiation of Candida albicans strains. Methods In total 123 Candida albicans strains (including 7 reference, 11 clinical unrelated, and 105 isolates from patients of two hospitals in Poland were examined using three genotyping methods: PCR MP, macrorestriction analysis of the chromosomal DNA by pulsed-field gel electrophoresis (REA-PFGE and RAPD techniques. Results The genotyping results of the PCR MP were compared with results from REA-PFGE and RAPD techniques giving 27, 26 and 25 unique types, respectively. The results showed that the PCR MP technique has at least the same discriminatory power as REA-PFGE and RAPD. Conclusion Data presented here show for the first time the evaluation of PCR MP technique for candidial strains differentiation and we propose that this can be used as a relatively simple and cheap technique for epidemiological studies in short period of time in hospital.

What is a microbiologist? A survey exploring the microbiology workforce.

Science.gov (United States)

Redfern, James; Verran, Joanna

2015-12-01

Microbiology has a long tradition of making inspirational, world-changing discovery. Microbiology now plays essential roles in many disciplines, leading to some microbiologists raising concern over the apparent loss of identity. An electronic survey was undertaken to capture the scientific identity (based on scientific discipline) of people for whom microbiology forms a part of their profession, in addition to information regarding their first degree (title, country and year in which the degree was completed) and the sector in which they currently work. A total of 447 responses were collected, representing 52 countries from which they gained their first degree. Biology was the most common first degree title (of 32 titles provided), while microbiologist was the most common scientific identity (of 26 identities provided). The data collected in this study gives a snapshot of the multidisciplinarity, specialism and evolving nature of the microbiology academic workforce. While the most common scientific identity chosen in this study was that of a microbiologist, it appears that the microbiological workforce is contributed to by a range of different disciplines, highlighting the cross-cutting, multidisciplined and essential role microbiology has within scientific endeavour. Perhaps, we should be less concerned with labels, and celebrate the success with which our discipline has delivered. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Making Microbiology Even Smaller!

Science.gov (United States)

Young, Linda Mull; Motz, Vicki Abrams

2013-01-01

We outline protocols for producing slant-minis (SLINIs) and mini-deeps (MEEPs) and examples of their use in simple microbiology experiments suitable for high school students. The principal benefits of these protocols are decreased cost associated with significantly reduced media use; easier, less expensive disposal of waste; and increased safety…

The evolution of teaching and learning medical microbiology and infectious diseases at NUS.

Science.gov (United States)

Taylor, M B; Chow, V T K

2005-07-01

Infectious diseases were rife during the early years of the Singapore Medical College, which was established in 1905. The current Department of Microbiology in the National University of Singapore (NUS) has its historical roots in the Departments of Bacteriology and Parasitology, which were established in 1925 and 1950 respectively. With the achievements since its inception, and with its present research focus on Infectious Diseases, Immunology, Applied and Environmental Microbiology, it is poised to face the microbiological challenges of the 21st century. Over the decades, the structure of the medical microbiology course in NUS has modernised, culminating in the current emphasis on its practical utility in clinical practice. Coordinated by the Department of Microbiology, the Microbiology and Infectious Diseases module and the Immunology module both adopt integrated multidisciplinary approaches that aim to introduce students to the language and fundamental concepts in microbiology, infectious diseases and immunology.

Transforming a Sequence of Microbiology Courses Using Student Profile Data

Directory of Open Access Journals (Sweden)

Rosa J. Buxeda

2009-12-01

Full Text Available 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.

Medical Devices; Immunology and Microbiology Devices; Classification of the Assayed Quality Control Material for Clinical Microbiology Assays. Final order.

Science.gov (United States)

2017-07-27

The Food and Drug Administration (FDA, Agency, or we) is classifying the assayed quality control material for clinical microbiology assays into class II (special controls). The special controls that will apply to the device are identified in this order and will be part of the codified language for the assayed quality control material for clinical microbiology assays' classification. The Agency is classifying the device into class II (special controls) to provide a reasonable assurance of safety and effectiveness of the device.

Application of droplet digital PCR for quantitative detection of Spiroplasma citri in comparison with real time PCR.

Directory of Open Access Journals (Sweden)

Yogita Maheshwari

Full Text Available Droplet digital polymerase chain reaction (ddPCR is a method for performing digital PCR that is based on water-oil emulsion droplet technology. It is a unique approach to measure the absolute copy number of nucleic acid targets without the need of external standards. This study evaluated the applicability of ddPCR as a quantitative detection tool for the Spiroplasma citri, causal agent of citrus stubborn disease (CSD in citrus. Two sets of primers, SP1, based on the spiral in housekeeping gene, and a multicopy prophage gene, SpV1 ORF1, were used to evaluate ddPCR in comparison with real time (quantitative PCR (qPCR for S. citri detection in citrus tissues. Standard curve analyses on tenfold dilution series showed that both ddPCR and qPCR exhibited good linearity and efficiency. However, ddPCR had a tenfold greater sensitivity than qPCR and accurately quantified up to one copy of spiralin gene. Receiver operating characteristic analysis indicated that the ddPCR methodology was more robust for diagnosis of CSD and the area under the curve was significantly broader compared to qPCR. Field samples were used to validate ddPCR efficacy and demonstrated that it was equal or better than qPCR to detect S. citri infection in fruit columella due to a higher pathogen titer. The ddPCR assay detected both the S. citri spiralin and the SpV1 ORF1 targets quantitatively with high precision and accuracy compared to qPCR assay. The ddPCR was highly reproducible and repeatable for both the targets and showed higher resilience to PCR inhibitors in citrus tissue extract for the quantification of S. citri compare to qPCR.

Detecting Newcastle disease virus in combination of RT-PCR with red blood cell absorption

Directory of Open Access Journals (Sweden)

Liu Chengqian

2011-05-01

Full Text Available Abstract Reverse transcription-polymerase chain reaction (RT-PCR has limited sensitivity when treating complicated samples, such as feces, waste-water in farms, and nucleic acids, protein rich tissue samples, all the factors may interfere with the sensitivity of PCR test or generate false results. In this study, we developed a sensitive RT-PCR, combination of red blood cell adsorption, for detecting Newcastle disease virus (NDV. One pair of primers which was highly homologous to three NDV pathotypes was designed according to the consensus nucleocapsid protein (NP gene sequence. To eliminate the interfere of microbes and toxic substances, we concentrated and purified NDV from varied samples utilizing the ability of NDV binding red blood cells (RBCs. The RT-PCR coupled with red blood cell adsorption was much more sensitive in comparison with regular RT-PCR. The approach could also be used to detect other viruses with the property of hemagglutination, such as influenza viruses.

Development of a Real-Time PCR for a Sensitive One-Step Coprodiagnosis Allowing both the Identification of Carnivore Feces and the Detection of Toxocara spp. and Echinococcus multilocularis.

Science.gov (United States)

Knapp, Jenny; Umhang, Gérald; Poulle, Marie-Lazarine; Millon, Laurence

2016-05-15

Studying the environmental occurrence of parasites of concern for humans and animals based on coprosamples is an expanding field of work in epidemiology and the ecology of health. Detecting and quantifying Toxocara spp. and Echinococcus multilocularis, two predominant zoonotic helminths circulating in European carnivores, in feces may help to better target measures for prevention. A rapid, sensitive, and one-step quantitative PCR (qPCR) allowing detection of E. multilocularis and Toxocara spp. was developed in the present study, combined with a host fecal test based on the identification of three carnivores (red fox, dog, and cat) involved in the life cycles of these parasites. A total of 68 coprosamples were collected from identified specimens from Vulpes vulpes, Canis lupus familiaris, Canis lupus, Felis silvestris catus, Meles meles, Martes foina, and Martes martes With DNA coprosamples, real-time PCR was performed in duplex with a qPCR inhibitor control specifically designed for this study. All the coprosample host identifications were confirmed by qPCR combined with sequencing, and parasites were detected and confirmed (E. multilocularis in red foxes and Toxocara cati in cats; 16% of samples presented inhibition). By combining parasite detection and quantification, the host fecal test, and a new qPCR inhibitor control, we created a technique with a high sensitivity that may considerably improve environmental studies of pathogens. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

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

International Nuclear Information System (INIS)

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

2012-01-01

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

Science.gov (United States)

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.

Iron oxide nanoparticles in modern microbiology and biotechnology.

Science.gov (United States)

Dinali, Ranmadugala; Ebrahiminezhad, Alireza; Manley-Harris, Merilyn; Ghasemi, Younes; Berenjian, Aydin

2017-08-01

Iron oxide nanoparticles (IONs) are one of the most developed and used nanomaterials in biotechnology and microbiology. These particles have unique physicochemical properties, which make them unique among nanomaterials. Therefore, many experiments have been conducted to develop facile synthesis methods for these particles and to make them biocompatible. Various effects of IONs on microorganisms have been reported. Depending on the microbial strain and nanoparticle (NP) concentration, IONs can stimulate or inhibit microbial growth. Due to the superparamagnetic properties of IONs, these NPs have used as nano sources of heat for hyperthermia in infected tissues. Antibiotic-loaded IONs are used for targeted delivery of chemical therapy direct to the infected organ and IONs have been used as a dirigible carrier for more potent antimicrobial nanomaterials such as silver nanoparticles. Magnetic NPs have been used for specific separation of pathogen and non-pathogen bacterial strains. Very recently, IONs were used as a novel tool for magnetic immobilization of microbial cells and process intensification in a biotechnological process. This review provides an overview of application of IONs in different microbial processes. Recommendations are also given for areas of future research.

Medical Microbiology: Deficits and Remedies

Science.gov (United States)

Gabridge, Michael G.

1974-01-01

Microbiology is a typical medical science in which basic information can have direct application. Yet, surveys and questionnaires of recent medical school graduates indicate a serious lack of retentiion in regard to basic biological science. (Author)

New Egyptian Journal of Microbiology

African Journals Online (AJOL)

The journal welcomes papers focusing on microbiological and/or immunological studies from medical or pharmaceutical perspectives. Research pieces on bacteria, fungi, viruses, protozoa, algae, spores, immunity, immune systems, health and pharmaceutical applications are highly relevant ...

Effectiveness of various cleaning and disinfectant products on Clostridium difficile spores of PCR ribotypes 010, 014 and 027

Directory of Open Access Journals (Sweden)

N. Kenters

2017-06-01

Full Text Available Abstract Background In healthcare facilities, Clostridium difficile infections spread by transmission of bacterial spores. Appropriate sporicidal disinfectants are needed to prevent development of clusters and outbreaks. In this study different cleaning/disinfecting wipes and sprays were tested for their efficacy against spores of distinctive C. difficile PCR ribotypes. Methods Four different products were tested; 1 hydrogen peroxide 1.5%; 2 glucoprotamin 1.5%; 3 a mixture of ethanol, propane and N-alkyl amino propyl glycine; and 4 a mixture of didecyldimonium chloride, benzalkonium chloride, polyaminopropyl, biguanide and dimenthicone as active ingredients. Tiles were contaminated with a test solution containing a concentration of 5x106CFU/ml spores of C. difficile strains belonging to PCR ribotypes 010, 014 or 027. The tiles were left to dry for an hour and then wiped or sprayed with one of the sprays or wipes as intended by the manufacturers. When products neutralized after 5 min, microbiological cultures and ATP measures were performed. Results Irrespective of the disinfection method, the microbial count log10 reduction of C. difficile PCR ribotype 010 was highest, followed by the reduction of C. difficile 014 and C. difficile 027. Overall, the wipes performed better than the sprays with the same active ingredient. On average, although not significantly, a difference in relative light units (RLU reduction between the wipes and sprays was found. The wipes had a higher RLU log10 reduction, but no significant difference for RLU reduction was observed between the different C. difficile strains (p = 0.16. Conclusion C. difficile spores of PCR ribotypes 014 and 027 strains are more difficult to eradicate than non-toxigenic PCR ribotype 010. In general, impregnated cleaning/disinfection wipes performed better than ready-to-use sprays. Wipes with hydrogen peroxide (1.5% showed the highest bactericidal activity.

Comparison between single PCR and nested PCR in detection of human papilloma viruses in paraffin-embedded OSCC and fresh oral mucosa.

Science.gov (United States)

Jalouli, Miranda; Jalouli, Jamshid; Ibrahim, Salah O; Hirsch, Jan-Michaél; Sand, Lars

2015-01-01

Infection with human papilloma virus (HPV) has been implicated as one of the risk factors for the development of oropharyngeal cancer. Many different HPV tests exist, and information regarding their specific technical, analytical, and clinical properties is increasing. This study aimed to compare the level of detection of HPV using two reliable polymerase chain reaction (PCR) methods, nested PCR (NPCR) and single PCR (SPCR), in archival paraffin-embedded oral squamous cell carcinoma (OSCC) samples and fresh oral mucosa specimens. The presence of HPV genome in two groups of tissue samples was analyzed: (i) 57 paraffin-embedded OSCC samples from Sudan and (ii) eight healthy fresh oral mucosal samples from Swedish volunteers. The specimens were tested by SPCR with primer pair MY9/MY11 and NPCR using GP5+/GP6+ primer sets. Eighteen (32%) out of the 57 paraffin-embedded OSCC samples, and five (62%) out of the eight fresh clinically healthy samples were found to be HPV-positive with NPCR. With SPCR, four (7%) out of the paraffin-embedded OSCC samples were HPV-positive. A statistically significant difference between HPV-positive and -negative samples was found when comparing NPCR and SPCR in OSCC and fresh oral mucosa (pnested PCR increased the positivity rate, efficiency rate and sensitivity of HPV detection in oral samples significantly and should be considered as the method of choice. Copyright © 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Evaluation of activities aimed at preventing microbiological risks in dental practice

Directory of Open Access Journals (Sweden)

Jolanta Szymańska

2013-02-01

Full Text Available Background: Microbiological contamination of water in dental unit waterlines (DUWL creates a risk of cross-infections, and is a source of biological risk factors in the work environment of a dentist. The aim of the study was to evaluate dentists' knowledge on DUWL microbiological contamination and the scope of activities/procedures they undertake to monitor it. Material and Methods: The questionnaire survey was conducted in 2010 among 107 Polish dentists using dental units in everyday clinical practice. Results: It has been found that in their daily practice, dentists do not follow procedures leading to reduction or elimination of microbiological contamination of dental unit reservoir water. They are not aware of microbiological contamination of DUWL that supply working handpieces with water. They are unaware of the principles of dealing with dental water and water supply systems or the health risk posed by microbiological contamination of unit water for a dental team and patients. Conclusions: It is necessary to provide dentists with information on microbiological contamination of water in dental units, on the correct procedures of handling water and waterlines that supply working handpieces with water. Med Pr 2013;64(1:11–17

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

Science.gov (United States)

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.

Estimating marginal properties of quantitative real-time PCR data using nonlinear mixed models

DEFF Research Database (Denmark)

Gerhard, Daniel; Bremer, Melanie; Ritz, Christian

2014-01-01

A unified modeling framework based on a set of nonlinear mixed models is proposed for flexible modeling of gene expression in real-time PCR experiments. Focus is on estimating the marginal or population-based derived parameters: cycle thresholds and ΔΔc(t), but retaining the conditional mixed mod...

Molecular diagnostic PCR handbook

International Nuclear Information System (INIS)

Viljoen, G.J.; Crowther, J.R.; Nel, L.H.

2005-01-01

The uses of nucleic acid-directed methods have increased significantly in the past five years and have made important contributions to disease control country programmes for improving national and international trade. These developments include the more routine use of PCR as a diagnostic tool in veterinary diagnostic laboratories. However, there are many problems associated with the transfer and particularly, the application of this technology. These include lack of consideration of: the establishment of quality-assured procedures, the required set-up of the laboratory and the proper training of staff. This can lead to a situation where results are not assured. This book gives a comprehensive account of the practical aspects of PCR and strong consideration is given to ensure its optimal use in a laboratory environment. This includes the setting-up of a PCR laboratory; Good Laboratory Practice and standardised PCR protocols to detect animal disease pathogens. Examples of Standard Operating Procedures as used in individual specialist laboratories and an outline of training materials necessary for PCR technology transfer are presented. The difficulties, advantages and disadvantages in PCR applications are explained and placed in context with other test systems. Emphasis is placed on the use of PCR for detection of pathogens, with a particular focus on diagnosticians and scientists from the developing world. It is hoped that this book will enable readers from various disciplines and levels of expertise to better judge the merits of PCR and to increase their skills and knowledge in order to assist in a more logical, efficient and assured use of this technology

Topic Outlines in Microbiology: An Instructor's Guide for Junior and Community Colleges.

Science.gov (United States)

American Society for Microbiology, Washington, DC.

This resource guide presents subject matter organized in outline form for four topical areas: introductory microbiology; medical microbiology; microbial genetics; and microbial physiology. The first two units comprise the two most frequently taught microbiology courses in community and junior colleges. The outlines for microbial genetics and…

Factors impacting on the microbiological quality and safety of ...

African Journals Online (AJOL)

Problems with the safety and shelf life of export hake have been raised by the Namibian fishing industry. This prompted an investigation into the factors that may have an impact on the microbiological quality and safety of processed hake. Samples were collected along the processing line; the general microbiological quality ...

The microbiology of Lascaux Cave

Czech Academy of Sciences Publication Activity Database

Bastian, F.; Jurado, V.; Nováková, Alena; Alabouvette, C.; Saiz-Jimenez, C.

2010-01-01

Roč. 156, č. 3 (2010), s. 644-652 ISSN 1350-0872 Institutional research plan: CEZ:AV0Z60660521 Keywords : Lascaux Cave * microbiology * Paleolithic paintings Subject RIV: EH - Ecology, Behaviour Impact factor: 2.957, year: 2010

Irradiation of ready meals for microbiological safety and shelf-life ...

African Journals Online (AJOL)

Microbiological quality of waakye and other ready-to-eat meals. ... and 14 meals prepared under the hazard analysis and critical control point (HACCP) plan were ... sauce and vegetable salad, exceeded the microbiological standards for such ...

Rapid detection of enterovirus in cerebrospinal fluid by a fully-automated PCR assay is associated with improved management of aseptic meningitis in adult patients.

Science.gov (United States)

Giulieri, Stefano G; Chapuis-Taillard, Caroline; Manuel, Oriol; Hugli, Olivier; Pinget, Christophe; Wasserfallen, Jean-Blaise; Sahli, Roland; Jaton, Katia; Marchetti, Oscar; Meylan, Pascal

2015-01-01

Enterovirus (EV) is the most frequent cause of aseptic meningitis (AM). Lack of microbiological documentation results in unnecessary antimicrobial therapy and hospitalization. To assess the impact of rapid EV detection in cerebrospinal fluid (CSF) by a fully-automated PCR (GeneXpert EV assay, GXEA) on the management of AM. Observational study in adult patients with AM. Three groups were analyzed according to EV documentation in CSF: group A = no PCR or negative PCR (n=17), group B = positive real-time PCR (n = 20), and group C = positive GXEA (n = 22). Clinical, laboratory and health-care costs data were compared. Clinical characteristics were similar in the 3 groups. Median turn-around time of EV PCR decreased from 60 h (IQR (interquartile range) 44-87) in group B to 5h (IQR 4-11) in group C (p<0.0001). Median duration of antibiotics was 1 (IQR 0-6), 1 (0-1.9), and 0.5 days (single dose) in groups A, B, and C, respectively (p < 0.001). Median length of hospitalization was 4 days (2.5-7.5), 2 (1-3.7), and 0.5 (0.3-0.7), respectively (p < 0.001). Median hospitalization costs were $5458 (2676-6274) in group A, $2796 (2062-5726) in group B, and $921 (765-1230) in group C (p < 0.0001). Rapid EV detection in CSF by a fully-automated PCR improves management of AM by significantly reducing antibiotic use, hospitalization length and costs. Copyright © 2014 Elsevier B.V. All rights reserved.

PCR-based verification of positive rapid diagnostic tests for intestinal protozoa infections with variable test band intensity.

Science.gov (United States)

Becker, Sören L; Müller, Ivan; Mertens, Pascal; Herrmann, Mathias; Zondie, Leyli; Beyleveld, Lindsey; Gerber, Markus; du Randt, Rosa; Pühse, Uwe; Walter, Cheryl; Utzinger, Jürg

2017-10-01

Stool-based rapid diagnostic tests (RDTs) for pathogenic intestinal protozoa (e.g. Cryptosporidium spp. and Giardia intestinalis) allow for prompt diagnosis and treatment in resource-constrained settings. Such RDTs can improve individual patient management and facilitate population-based screening programmes in areas without microbiological laboratories for confirmatory testing. However, RDTs are difficult to interpret in case of 'trace' results with faint test band intensities and little is known about whether such ambiguous results might indicate 'true' infections. In a longitudinal study conducted in poor neighbourhoods of Port Elizabeth, South Africa, a total of 1428 stool samples from two cohorts of schoolchildren were examined on the spot for Cryptosporidium spp. and G. intestinalis using an RDT (Crypto/Giardia DuoStrip; Coris BioConcept). Overall, 121 samples were positive for G. intestinalis and the RDT suggested presence of cryptosporidiosis in 22 samples. After a storage period of 9-10 months in cohort 1 and 2-3 months in cohort 2, samples were subjected to multiplex PCR (BD Max™ Enteric Parasite Panel, Becton Dickinson). Ninety-three percent (112/121) of RDT-positive samples for G. intestinalis were confirmed by PCR, with a correlation between RDT test band intensity and quantitative pathogen load present in the sample. For Cryptosporidium spp., all positive RDTs had faintly visible lines and these were negative on PCR. The performance of the BD Max™ PCR was nearly identical in both cohorts, despite the prolonged storage at disrupted cold chain conditions in cohort 1. The Crypto/Giardia DuoStrip warrants further validation in communities with a high incidence of diarrhoea. Copyright © 2017 Elsevier B.V. All rights reserved.

Environmental Monitoring Of Microbiological Laboratory: Expose Plate Method

International Nuclear Information System (INIS)

Yahaya Talib; Othman Mahmud; Noraisyah Mohd Yusof; Asmah Mohibat; Muhamad Syazwan Zulkifli

2013-01-01

Monitoring of microorganism is important and conducted regularly on environment of microbiological laboratory at Medical Technology Division. Its objective is to ensure the quality of working environment is maintained according to microbial contamination, consequently to assure the quality of microbiological tests. This paper presents report of environmental monitoring since year 2007. The test involved was bacterial colony counts after the growth media was exposed to air at identified location. (author)

PCR screening reveals considerable unexploited biosynthetic potential of ansamycins and a mysterious family of AHBA-containing natural products in actinomycetes.

Science.gov (United States)

Wang, H-X; Chen, Y-Y; Ge, L; Fang, T-T; Meng, J; Liu, Z; Fang, X-Y; Ni, S; Lin, C; Wu, Y-Y; Wang, M-L; Shi, N-N; He, H-G; Hong, K; Shen, Y-M

2013-07-01

Ansamycins are a family of macrolactams that are synthesized by type I polyketide synthase (PKS) using 3-amino-5-hydroxybenzoic acid (AHBA) as the starter unit. Most members of the family have strong antimicrobial, antifungal, anticancer and/or antiviral activities. We aimed to discover new ansamycins and/or other AHBA-containing natural products from actinobacteria. Through PCR screening of AHBA synthase gene, we identified 26 AHBA synthase gene-positive strains from 206 plant-associated actinomycetes (five positives) and 688 marine-derived actinomycetes (21 positives), representing a positive ratio of 2·4-3·1%. Twenty-five ansamycins, including eight new compounds, were isolated from six AHBA synthase gene-positive strains through TLC-guided fractionations followed by repeated column chromatography. To gain information about those potential ansamycin gene clusters whose products were unknown, seven strains with phylogenetically divergent AHBA synthase genes were subjected to fosmid library construction. Of the seven gene clusters we obtained, three show characteristics for typical ansamycin gene clusters, and other four, from Micromonospora spp., appear to lack the amide synthase gene, which is unusual for ansamycin biosynthesis. The gene composition of these four gene clusters suggests that they are involved in the biosynthesis of a new family of hybrid PK-NRP compounds containing AHBA substructure. PCR screening of AHBA synthase is an efficient approach to discover novel ansamycins and other AHBA-containing natural products. This work demonstrates that the AHBA-based screening method is a useful approach for discovering novel ansamycins and other AHBA-containing natural products from new microbial resources. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

Pneumocystis PCR: It Is Time to Make PCR the Test of Choice.

Science.gov (United States)

Doyle, Laura; Vogel, Sherilynn; Procop, Gary W

2017-01-01

The testing strategy for Pneumocystis at the Cleveland Clinic changed from toluidine blue staining to polymerase chain reaction (PCR). We studied the differences in positivity rates for these assays and compared each with the detection of Pneumocystis in companion specimens by cytology and surgical pathology. We reviewed the results of all Pneumocystis test orders 1 year before and 1 year after the implementation of a Pneumocystis -specific PCR. We also reviewed the corresponding cytology and surgical pathology results, if performed. Finally, we reviewed the medical records of patients with rare Pneumocystis detected by PCR in an effort to differentiate colonization vs true disease. Toluidine blue staining and surgical pathology had similar sensitivities and negative predictive values, both of which were superior to cytology. There was a >4-fold increase in the annual detection of Pneumocystis by PCR compared with toluidine blue staining (toluidine blue staining: 11/1583 [0.69%] vs PCR: 44/1457 [3.0%]; chi-square P < .001). PCR detected 1 more case than surgical pathology and was far more sensitive than cytology. Chart review demonstrated that the vast majority of patients with rare Pneumocystis detected were immunosuppressed, had radiologic findings supportive of this infection, had no other pathogens detected, and were treated for pneumocystosis by the clinical team. PCR was the most sensitive method for the detection of Pneumocystis and should be considered the diagnostic test of choice. Correlation with clinical and radiologic findings affords discrimination of early true disease from the far rarer instances of colonization.

Salinidade, sodicidade e propriedades microbiológicas de Argissolo cultivado com erva-sal e irrigado com rejeito salino Salinity, sodicity and microbiological properties of an Ultisol cultivated with saltbush and irrigated with saline effluents

Directory of Open Access Journals (Sweden)

Célia Maria Maganhotto de Souza Silva

2008-10-01

Full Text Available O objetivo deste trabalho foi avaliar o efeito da irrigação com rejeito da dessalinização, oriundo de tanques de produção de tilápia-rosa, sobre as propriedades químicas e microbiológicas de solos cultivados com erva-sal (Atriplex nummularia Lindl.. Quatro áreas foram usadas, das quais duas foram irrigadas com rejeito salino e cultivadas, durante um e cinco anos, com erva-sal. As outras duas áreas foram conduzidas sem irrigação: uma cultivada com vegetação natural e outra com a halófita. Avaliaram-se os parâmetros relativos à salinidade e sodicidade do solo, e também as seguintes características: carbono da biomassa microbiana (Cmic; relação Cmic/carbono orgânico; atividade das enzimas fosfatase ácida, fosfatase alcalina, beta-glucosidase, protease, L-asparaginase, L-glutaminase. A adição de sais afetou as propriedades físicas e químicas dos solos irrigados com rejeito salino, com tendência à salinização e sodificação. A salinidade afetou as propriedades microbiológicas nos solos irrigados, mas o cultivo da halófita favoreceu a produção das enzimas estudadas. O cultivo da erva-sal em áreas que recebem rejeito salino pela irrigação melhora a qualidade biológica dos solos e sua fertilidade, mas não impede a salinização.The objective of this work was to evaluate the effects of irrigation with saline effluents, from red tilapia production ponds, on chemical and microbiological properties of soils cultivated with saltbush (Atriplex nummularia Lindl. Four areas were used, from which two were irrigated with saline waste and cultivated with A. nummularia, during one and five years. The other two areas were not irrigated, and one was cultivated with natural vegetation and the other with the halophyte. The parameters related to soil salinity and sodicity were evaluated, as well as the following characteristics: microbial biomass carbon (Cmic; Cmic/organic carbon; the activity of acid and alcaline phosphatase

Comparison of allele-specific PCR, created restriction-site PCR, and PCR with primer-introduced restriction analysis methods used for screening complex vertebral malformation carriers in Holstein cattle

Science.gov (United States)

Altınel, Ahmet

2017-01-01

Complex vertebral malformation (CVM) is an inherited, autosomal recessive disorder of Holstein cattle. The aim of this study was to compare sensitivity, specificity, positive and negative predictive values, accuracy, and rapidity of allele-specific polymerase chain reaction (AS-PCR), created restriction-site PCR (CRS-PCR), and PCR with primer-introduced restriction analysis (PCR-PIRA), three methods used in identification of CVM carriers in a Holstein cattle population. In order to screen for the G>T mutation in the solute carrier family 35 member A3 (SLC35A3) gene, DNA sequencing as the gold standard method was used. The prevalence of carriers and the mutant allele frequency were 3.2% and 0.016, respectively, among Holstein cattle in the Thrace region of Turkey. Among the three methods, the fastest but least accurate was AS-PCR. Although the rapidity of CRS-PCR and PCR-PIRA were nearly equal, the accuracy of PCR-PIRA was higher than that of CRS-PCR. Therefore, among the three methods, PCR-PIRA appears to be the most efficacious for screening of mutant alleles when identifying CVM carriers in a Holstein cattle population. PMID:28927256

Analytical Performance of Four Polymerase Chain Reaction (PCR and Real Time PCR (qPCR Assays for the Detection of Six Leishmania Species DNA in Colombia

Directory of Open Access Journals (Sweden)

Cielo M. León

2017-10-01

Full Text Available Leishmaniasis comprises a spectrum of parasitic diseases caused by protozoans of the genus Leishmania. Molecular tools have been widely employed for the detection of Leishmania due to its high sensitivity and specificity. However, the analytical performance of molecular platforms as PCR and real time PCR (qPCR including a wide variety of molecular markers has never been evaluated. Herein, the aim was to evaluate the analytical performance of 4 PCR-based assays (designed on four different targets and applied on conventional and real-time PCR platforms. We evaluated the analytical performance of conventional PCR and real time PCR, determining exclusivity and inclusivity, Anticipated Reportable Range (ARR, limit of detection (LoD and accuracy using primers directed to kDNA, HSP70, 18S and ITS-1 targets. We observed that the kDNA was the most sensitive but does not meet the criterion of exclusivity. The HSP70 presented a higher LoD in conventional PCR and qPCR in comparison with the other markers (1 × 101 and 1 × 10-1 equivalent parasites/mL respectively and had a higher coefficient of variation in qPCR. No statistically significant differences were found between the days of the test with the four molecular markers. The present study revealed that the 18S marker presented the best performance in terms of analytical sensitivity and specificity for the qPCR in the species tested (species circulating in Colombia. Therefore, we recommend to explore the analytical and diagnostic performance in future studies using a broader number of species across America.

Analytical Performance of Four Polymerase Chain Reaction (PCR) and Real Time PCR (qPCR) Assays for the Detection of Six Leishmania Species DNA in Colombia

Science.gov (United States)

León, Cielo M.; Muñoz, Marina; Hernández, Carolina; Ayala, Martha S.; Flórez, Carolina; Teherán, Aníbal; Cubides, Juan R.; Ramírez, Juan D.

2017-01-01

Leishmaniasis comprises a spectrum of parasitic diseases caused by protozoans of the genus Leishmania. Molecular tools have been widely employed for the detection of Leishmania due to its high sensitivity and specificity. However, the analytical performance of molecular platforms as PCR and real time PCR (qPCR) including a wide variety of molecular markers has never been evaluated. Herein, the aim was to evaluate the analytical performance of 4 PCR-based assays (designed on four different targets) and applied on conventional and real-time PCR platforms. We evaluated the analytical performance of conventional PCR and real time PCR, determining exclusivity and inclusivity, Anticipated Reportable Range (ARR), limit of detection (LoD) and accuracy using primers directed to kDNA, HSP70, 18S and ITS-1 targets. We observed that the kDNA was the most sensitive but does not meet the criterion of exclusivity. The HSP70 presented a higher LoD in conventional PCR and qPCR in comparison with the other markers (1 × 101 and 1 × 10-1 equivalent parasites/mL respectively) and had a higher coefficient of variation in qPCR. No statistically significant differences were found between the days of the test with the four molecular markers. The present study revealed that the 18S marker presented the best performance in terms of analytical sensitivity and specificity for the qPCR in the species tested (species circulating in Colombia). Therefore, we recommend to explore the analytical and diagnostic performance in future studies using a broader number of species across America. PMID:29046670

Quality in the molecular microbiology laboratory.

Science.gov (United States)

Wallace, Paul S; MacKay, William G

2013-01-01

In the clinical microbiology laboratory advances in nucleic acid detection, quantification, and sequence analysis have led to considerable improvements in the diagnosis, management, and monitoring of infectious diseases. Molecular diagnostic methods are routinely used to make clinical decisions based on when and how to treat a patient as well as monitor the effectiveness of a therapeutic regime and identify any potential drug resistant strains that may impact on the long term patient treatment program. Therefore, confidence in the reliability of the result provided by the laboratory service to the clinician is essential for patient treatment. Hence, suitable quality assurance and quality control measures are important to ensure that the laboratory methods and service meet the necessary regulatory requirements both at the national and international level. In essence, the modern clinical microbiology laboratory ensures the appropriateness of its services through a quality management system that monitors all aspects of the laboratory service pre- and post-analytical-from patient sample receipt to reporting of results, from checking and upholding staff competency within the laboratory to identifying areas for quality improvements within the service offered. For most European based clinical microbiology laboratories this means following the common International Standard Organization (ISO9001) framework and ISO15189 which sets out the quality management requirements for the medical laboratory (BS EN ISO 15189 (2003) Medical laboratories-particular requirements for quality and competence. British Standards Institute, Bristol, UK). In the United States clinical laboratories performing human diagnostic tests are regulated by the Centers for Medicare and Medicaid Services (CMS) following the requirements within the Clinical Laboratory Improvement Amendments document 1988 (CLIA-88). This chapter focuses on the key quality assurance and quality control requirements within the

Water Microbiology. Bacterial Pathogens and Water

Directory of Open Access Journals (Sweden)

João P. S. Cabral

2010-10-01

Full Text Available Water is essential to life, but many people do not have access to clean and safe drinking water and many die of waterborne bacterial infections. In this review a general characterization of the most important bacterial diseases transmitted through water—cholera, typhoid fever and bacillary dysentery—is presented, focusing on the biology and ecology of the causal agents and on the diseases’ characteristics and their life cycles in the environment. The importance of pathogenic Escherichia coli strains and emerging pathogens in drinking water-transmitted diseases is also briefly discussed. Microbiological water analysis is mainly based on the concept of fecal indicator bacteria. The main bacteria present in human and animal feces (focusing on their behavior in their hosts and in the environment and the most important fecal indicator bacteria are presented and discussed (focusing on the advantages and limitations of their use as markers. Important sources of bacterial fecal pollution of environmental waters are also briefly indicated. In the last topic it is discussed which indicators of fecal pollution should be used in current drinking water microbiological analysis. It was concluded that safe drinking water for all is one of the major challenges of the 21st century and that microbiological control of drinking water should be the norm everywhere. Routine basic microbiological analysis of drinking water should be carried out by assaying the presence of Escherichia coli by culture methods. Whenever financial resources are available, fecal coliform determinations should be complemented with the quantification of enterococci. More studies are needed in order to check if ammonia is reliable for a preliminary screening for emergency fecal pollution outbreaks. Financial resources should be devoted to a better understanding of the ecology and behavior of human and animal fecal bacteria in environmental waters.

Water microbiology. Bacterial pathogens and water.

Science.gov (United States)

Cabral, João P S

2010-10-01

Water is essential to life, but many people do not have access to clean and safe drinking water and many die of waterborne bacterial infections. In this review a general characterization of the most important bacterial diseases transmitted through water-cholera, typhoid fever and bacillary dysentery-is presented, focusing on the biology and ecology of the causal agents and on the diseases' characteristics and their life cycles in the environment. The importance of pathogenic Escherichia coli strains and emerging pathogens in drinking water-transmitted diseases is also briefly discussed. Microbiological water analysis is mainly based on the concept of fecal indicator bacteria. The main bacteria present in human and animal feces (focusing on their behavior in their hosts and in the environment) and the most important fecal indicator bacteria are presented and discussed (focusing on the advantages and limitations of their use as markers). Important sources of bacterial fecal pollution of environmental waters are also briefly indicated. In the last topic it is discussed which indicators of fecal pollution should be used in current drinking water microbiological analysis. It was concluded that safe drinking water for all is one of the major challenges of the 21st century and that microbiological control of drinking water should be the norm everywhere. Routine basic microbiological analysis of drinking water should be carried out by assaying the presence of Escherichia coli by culture methods. Whenever financial resources are available, fecal coliform determinations should be complemented with the quantification of enterococci. More studies are needed in order to check if ammonia is reliable for a preliminary screening for emergency fecal pollution outbreaks. Financial resources should be devoted to a better understanding of the ecology and behavior of human and animal fecal bacteria in environmental waters.

IDENTIFIKASI DAGING BABI MENGGUNAKAN METODE PCR-RFLP GEN Cytochrome b DAN PCR PRIMER SPESIFIK GEN AMELOGENIN (Pork Identification Using PCR-RFLP of Cytochrome b Gene and Species Specific PCR of Amelogenin Gene

Directory of Open Access Journals (Sweden)

Yuny Erwanto

2013-03-01

Full Text Available A polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP and species specific PCR methods had been applied for identifying pork in mixture of meat. Pork sample in various levels (1, 3, 5 and 10% was prepared in mixture with beef, chicken and mutton. The primary CYTb1 and CYTb2 were designed in the mitochondrial cytochrome b b (cytochrome b gene and PCR successfully amplified fragments of 359 bp. To distinguish pig species existence, the amplified PCR products of mitochondrial DNA were cut by BseDI restriction enzyme. The result showed that pig mitochondrial DNA was cut into 131 and 228 bp fragments. A polymerase chain reaction (PCR method based on the nucleotide sequence variation in the amelogenin gene has been chosen for the specific identification of pork DNAs in mixture meat. The primers designed generated specific fragments of 353 and 312 bp length for pork. The specificity of the primary designed was tested on 4 animal species including pig, cattle, chicken and goat species. Analysis of experimental mixture meat demonstrated that 1% of raw pork tissues could be detected using PCR-RFLP with BseDI restriction enzyme but detection using species-specific PCR showed the cross reactivity to beef, chicken and mutton. The cytochrome b PCR-RFLP species identification assay yielded excellent results for identification of pig species. PCR-RFLP is a potentially reliable technique for detection of the existence of pork in animal food product for Halal authentication. Keywords: Pork identification, cytochrome b, amelogenin, polymerase chain reaction   ABSTRAK   Penelitian ini dilakukan untuk mengaplikasikan metode deteksi daging babi dalam campuan daging dengan sapi, kambing dan ayam melalui PCR-RFLP dan PCR dengan primer spesifik untuk babi. Level kontaminasi daging babi dibuat sebesar 1, 3, 5 dan 10% dari total daging dalam campuran. Metode PCR-RFLP menggunakan sepasang primer yaitu gen cytochrome b dari mitokondria yang

Comparative evaluation of conventional RT-PCR and real-time RT-PCR (RRT-PCR) for detection of avian metapneumovirus subtype A

OpenAIRE

Ferreira, HL; Spilki, FR; dos Santos, MMAB; de Almeida, RS; Arns, CW

2009-01-01

Avian metapneumovirus (AMPV) belongs to Metapneumovirus genus of Paramyxoviridae family. Virus isolation, serology, and detection of genomic RNA are used as diagnostic methods for AMPV. The aim of the present study was to compare the detection of six subgroup A AMPV isolates (AMPV/A) viral RNA by using different conventional and real time RT-PCR methods. Two new RT-PCR tests and two real time RT-PCR tests, both detecting fusion (F) gene and nucleocapsid (N) gene were compared with an establis...

Inverse fusion PCR cloning.

Directory of Open Access Journals (Sweden)

Markus Spiliotis

Full Text Available Inverse fusion PCR cloning (IFPC is an easy, PCR based three-step cloning method that allows the seamless and directional insertion of PCR products into virtually all plasmids, this with a free choice of the insertion site. The PCR-derived inserts contain a vector-complementary 5'-end that allows a fusion with the vector by an overlap extension PCR, and the resulting amplified insert-vector fusions are then circularized by ligation prior transformation. A minimal amount of starting material is needed and experimental steps are reduced. Untreated circular plasmid, or alternatively bacteria containing the plasmid, can be used as templates for the insertion, and clean-up of the insert fragment is not urgently required. The whole cloning procedure can be performed within a minimal hands-on time and results in the generation of hundreds to ten-thousands of positive colonies, with a minimal background.

Veterinary Microbiology, 3rd Edition

Science.gov (United States)

Veterinary Microbiology, Third Edition is organized into four sections and begins with an updated and expanded introductory section on infectious disease pathogenesis, diagnosis and clinical management. The second section covers bacterial and fungal pathogens, and the third section describes viral d...

Biomedical mass spectrometry in today's and tomorrow's clinical microbiology laboratories

NARCIS (Netherlands)

A.F. van Belkum (Alex); M. Welker (Martin); M. Erhard (Marcel); S. Chatellier (Sonia)

2012-01-01

textabstractClinical microbiology is a conservative laboratory exercise where base technologies introduced in the 19th century remained essentially unaltered. High-tech mass spectrometry (MS) has changed that. Within a few years following its adaptation to microbiological diagnostics, MS has been

Usefulness of Two Aspergillus PCR Assays and Aspergillus Galactomannan and β-d-Glucan Testing of Bronchoalveolar Lavage Fluid for Diagnosis of Chronic Pulmonary Aspergillosis.

Science.gov (United States)

Urabe, Naohisa; Sakamoto, Susumu; Sano, Go; Suzuki, Junko; Hebisawa, Akira; Nakamura, Yasuhiko; Koyama, Kazuya; Ishii, Yoshikazu; Tateda, Kazuhiro; Homma, Sakae

2017-06-01

We evaluated the usefulness of an Aspergillus galactomannan (GM) test, a β-d-glucan (βDG) test, and two different Aspergillus PCR assays of bronchoalveolar lavage fluid (BALF) samples for the diagnosis of chronic pulmonary aspergillosis (CPA). BALF samples from 30 patients with and 120 patients without CPA were collected. We calculated the sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for each test individually and in combination with other tests. The optical density index values, as determined by receiver operating characteristic analysis, for the diagnosis of CPA were 0.5 and 100 for GM and βDG testing of BALF, respectively. The sensitivity and specificity of the GM test, βDG test, and PCR assays 1 and 2 were 77.8% and 90.0%, 77.8% and 72.5%, 86.7% and 84.2%, and 66.7% and 94.2%, respectively. A comparison of the PCR assays showed that PCR assay 1 had a better sensitivity, a better negative predictive value, and a better negative likelihood ratio and PCR assay 2 had a better specificity, a better positive predictive value, and a better positive likelihood ratio. The combination of the GM and βDG tests had the highest diagnostic odds ratio. The combination of the GM and βDG tests on BALF was more useful than any single test for diagnosing CPA. Copyright © 2017 American Society for Microbiology.

American Society for Microbiology resources in support of an evidence-based approach to teaching microbiology.

Science.gov (United States)

Merkel, Susan M

2016-08-01

Numerous national reports have addressed the need for changing how science courses in higher education are taught, so that students develop a deeper understanding of critical concepts and the analytical and cognitive skills needed to address future challenges. This review presents some evidence-based approaches to curriculum development and teaching. Results from discipline-based education research indicate that it is critically important for educators to formulate learning goals, provide frequent and authentic assessments and actively engage students in their learning. Professional societies can play a role in helping to put these changes into practice. To this end, the American Society for Microbiology has developed a number of educational programs and resources, which are described here to encourage the implementation of student-centered learning in microbiology education. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Infection control team (ICT) in cooperation with microbiology laboratories].

Science.gov (United States)

Okazaki, Mitsuhiro

2012-10-01

Infection control as a medical safety measure is an important issue in all medical facilities. In order to tackle this measure, cooperation between the infection control team (ICT) and microbiological laboratory is indispensable. Multiple drug-resistant bacteria have shifted from Gram-positive bacteria to Gram-negative bacilli within the last ten years. There are also a variety of bacilli, complicating the examination method and test results further. Therefore, cooperation between the ICT and microbiological laboratory has become important to understand examination results and to use them. In order to maintain functional cooperation, explanatory and communicative ability between the microbiological laboratory and ICT is required every day. Such positive information exchange will develop into efficient and functional ICT activity.

Comparison of nested PCR and qPCR for the detection and quantitation of BoHV6 DNA.

Science.gov (United States)

Kubiś, Piotr; Materniak, Magdalena; Kuźmak, Jacek

2013-12-01

Nested PCR and qPCR (quantitative PCR) tests based on glycoprotein B (gB) gene were designed for detecting Bovine herpesvirus 6 (BoHV6) in bovine whole blood samples and wild ruminant blood clots (deer and roe-deer). This virus, commonly known as BLHV (bovine lymphotropic herpesvirus) belongs to the Herpesviridae family, subfamily Gammaherpesvirinae and Macavirus genus. DNA isolated from 92 dairy cow blood samples and 69 wild ruminant clots were examined for the presence of BoHV6 using nested PCR and qPCR tests. Viral DNA was detected by using nested PCR in 59 out of 92 bovine blood samples (64.1%), and by qPCR in 68 out of 92 bovine blood samples (73.9%), but none out of 69 DNA samples isolated from wild ruminant blood clots, was positive in both assays. The specificity of nested PCR and qPCR was confirmed by using BoHV1, BoHV4, BoHV6, BFV, BIV, and BLV DNA. The sensitivity of nested PCR and qPCR was determined using a serially 10-fold diluted vector pCR2.1HgB (2 × 10(0)-2 × 10(6)copies/reaction). In this testing, qPCR was more sensitive than the nested PCR, detecting two copies of BoHV6 whilst the limit of detection for nested PCR was 20 copies. In all qPCR assays, the coefficients of determination (R(2)) ranged between 0.990 and 0.999, and the calculated amplification efficiencies (Eff%) within the range of 89.7-106.9. The intra- and inter-assay CV (coefficient of variation) values did not exceed 4%. Copyright © 2013 Elsevier B.V. All rights reserved.

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

Science.gov (United States)

2011-11-21

... Multiplexed Microbiology Devices: Their clinical application and public health/clinical needs; inclusion of...] 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...

A combined RT-PCR and dot-blot hybridization method reveals the coexistence of SJNNV and RGNNV betanodavirus genotypes in wild meagre (Argyrosomus regius).

Science.gov (United States)

Lopez-Jimena, B; Cherif, N; Garcia-Rosado, E; Infante, C; Cano, I; Castro, D; Hammami, S; Borrego, J J; Alonso, M C

2010-10-01

To detect the possible coexistence of striped jack nervous necrosis virus (SJNNV) and red-spotted grouper nervous necrosis virus (RGNNV) genotypes in a single fish, a methodology based on the combination of PCR amplification and blot hybridization has been developed and applied in this study. The degenerate primers designed for the PCR procedure target the T4 region within the capsid gene, resulting in the amplification of both genotypes. The subsequent hybridization of these amplification products with two different specific digoxigenin-labelled probes resulted in the identification of both genotypes separately. The application of the RT-PCR protocol to analyse blood samples from asymptomatic wild meagre (Argyrosomus regius) specimens has shown a 46.87% of viral nervous necrosis virus carriers. The combination of RT-PCR and blot hybridization increases the detection rate up to 90.62%, and, in addition, it has shown the coexistence of both genotypes in 18 out of the 32 specimens analysed (56.25%). This study reports the coexistence of betanodaviruses belonging to two different genotypes (SJNNV and RGNNV) in wild fish specimens. This is the first report demonstrating the presence of SJNNV and RGNNV genotypes in the same specimen. This study also demonstrates a carrier state in this fish species for the first time. © 2010 The Authors. Journal compilation © 2010 The Society for Applied Microbiology.

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

Science.gov (United States)

2011-08-08

... microbiology/MCM device, their clinical application and public health/clinical needs and quality criteria for... topics: 1. Clinical Application of Highly Multiplexed Microbiology Devices: Their clinical application... to evaluate the analytical and clinical performance of highly multiplexed microbiology devices...

Rheological and microbiological study of flour treated by irradiation

International Nuclear Information System (INIS)

Laabidi, Othmen

2007-01-01

the aim this work is to study the effectiveness of radio treatment and its effect on the conservation of flour and their various parameters (physico-chemical and rheological). The flour has been treated with different doses (0, 0.75, 1.5 and 3 kGy), physico-chemical, rheological, microbiological and sensory analyses were made.The results show that the irradiation as a treatment for decontamination gave a highly effective. Indeed, a dose of 1.5 kGy allows a total destruction of yeasts and molds. Thus, from the point of view physico-chemical, increasing the dose of radiation causes a change in physical and chemical properties and rheological of flour. for the characteristics of bread, increasing the dose of radiation affects the quality of bread. (Author). 38 refs

Microbiologically induced corrosion of carbon steel under continuous flow conditions

International Nuclear Information System (INIS)

Tunaru, Mariana; Dragomir, Maria; Voicu, Anca

2008-01-01

Microbiologically induced corrosion is the label generally applied to corrosion involving the action of bacteria on metal surfaces. While different combinations of bacterial species, materials and chemical constituents are interrelated factors, stagnant water is the factor most often mentioned in reported cases. This paper presents the results obtained regarding the testing of microbiologically induced corrosion of carbon steel under continuous flow conditions in the presence of iron-oxidizing bacteria. The tests were performed on coupons of SA106gr.B exposed both in stagnant conditions and in flow conditions. The surfaces of these coupons were studied by metallographic technique, while the developed biofilms were analysed using microbiological technique. The correlation of all the results which were obtained emphasized that the minimizing the occurrence of stagnant or low-flow conditions can prove effective in reducing the risk of microbiologically induced corrosion in plant cooling-water systems. (authors)

Physical-chemical, microbiological and sensory evaluation of spicy soybean paste

Directory of Open Access Journals (Sweden)

Daniela Cristina Faria Vieira

2016-10-01

Full Text Available This study aimed to develop a spicy soybean paste. Three formulations of spicy soybean paste were prepared, and then submitted to prior microbiological and sensory acceptance test with 50 untrained tasters. The most accepted formulation was evaluated on the microbiological quality during its shelf life. Significant differences were found (p <0.05 for the attributes flavor, aroma, texture and overall impression for the formulation B of spicy soybean paste, the most accepted of the two. It was found that the microbiological analyzes are within the established by the Technical Regulation on microbiological standards for food nº 12 of January 2nd, 2001. The mean values found for the physicochemical analyzes were 38.93% for moisture, 11.00% for lipids, proteins and 11.12% to 6.85% for ash content. The spicy soybean paste is a good food option, presenting good sensory acceptance.

Tools for Microbiological risk assessment

DEFF Research Database (Denmark)

Bassett, john; Nauta, Maarten; Lindqvist, Roland

can increase the understanding of microbiological risks in foods. It is timely to inform food safety professionals about the availability and utility of MRA tools. Therefore, the focus of this report is to aid the food safety manager by providing a concise summary of the tools available for the MRA......Microbiological Risk Assessment (MRA) has emerged as a comprehensive and systematic approach for addressing the risk of pathogens in specific foods and/or processes. At government level, MRA is increasingly recognised as a structured and objective approach to understand the level of risk in a given...... food/pathogen scenario. Tools developed so far support qualitative and quantitative assessments of the risk that a food pathogen poses to a particular population. Risk can be expressed as absolute numbers or as relative (ranked) risks. The food industry is beginning to appreciate that the tools for MRA...

Using the Primary Literature in an Allied Health Microbiology Course

Directory of Open Access Journals (Sweden)

Donald P. Breakwell

2009-12-01

Full Text Available A strategy was adapted for using the primary literature to foster active learning in an allied health microbiology course. Recent journal articles were selected that underscored the fundamental microbiological principles to be learned in each course unit. At the beginning of the semester, students were taught the relationship between the layout of scientific articles and the scientific method. During the rest of the semester, students were oriented to the topic of each paper by viewing videos from Unseen Life on Earth: an Introduction to Microbiology, reading assigned pages from the text, and participating in mini-lectures and discussions. After all preparatory material was completed, a paper was read and discussed in small groups and as a class. Students were assessed using daily reading quizzes and end-of-unit concept quizzes. While reading quizzes averaged approximately 93%, concept quiz grades averaged approximately 82%. Student recognition of the terms used in each unit’s scientific article was assessed with pre-read and post-read wordlists. For the self-assessment, the percent change between pre-read and post-read word cognition was, as expected, highly significant. Approximately 80% of students agreed that reading the scientific articles was a valuable part of the class and that it provided meaning to their study of microbiology. Using the primary scientific literature facilitated active learning in and out of the classroom. This study showed that introducing the scientific literature in an allied health microbiology class can be an effective way of teaching microbiology by providing meaning through the current literature and understanding of the scientific method.

Multiplex enrichment quantitative PCR (ME-qPCR): a high-throughput, highly sensitive detection method for GMO identification.

Science.gov (United States)

Fu, Wei; Zhu, Pengyu; Wei, Shuang; Zhixin, Du; Wang, Chenguang; Wu, Xiyang; Li, Feiwu; Zhu, Shuifang

2017-04-01

Among all of the high-throughput detection methods, PCR-based methodologies are regarded as the most cost-efficient and feasible methodologies compared with the next-generation sequencing or ChIP-based methods. However, the PCR-based methods can only achieve multiplex detection up to 15-plex due to limitations imposed by the multiplex primer interactions. The detection throughput cannot meet the demands of high-throughput detection, such as SNP or gene expression analysis. Therefore, in our study, we have developed a new high-throughput PCR-based detection method, multiplex enrichment quantitative PCR (ME-qPCR), which is a combination of qPCR and nested PCR. The GMO content detection results in our study showed that ME-qPCR could achieve high-throughput detection up to 26-plex. Compared to the original qPCR, the Ct values of ME-qPCR were lower for the same group, which showed that ME-qPCR sensitivity is higher than the original qPCR. The absolute limit of detection for ME-qPCR could achieve levels as low as a single copy of the plant genome. Moreover, the specificity results showed that no cross-amplification occurred for irrelevant GMO events. After evaluation of all of the parameters, a practical evaluation was performed with different foods. The more stable amplification results, compared to qPCR, showed that ME-qPCR was suitable for GMO detection in foods. In conclusion, ME-qPCR achieved sensitive, high-throughput GMO detection in complex substrates, such as crops or food samples. In the future, ME-qPCR-based GMO content identification may positively impact SNP analysis or multiplex gene expression of food or agricultural samples. Graphical abstract For the first-step amplification, four primers (A, B, C, and D) have been added into the reaction volume. In this manner, four kinds of amplicons have been generated. All of these four amplicons could be regarded as the target of second-step PCR. For the second-step amplification, three parallels have been taken for

A survey of tools for the analysis of quantitative PCR (qPCR) data.

Science.gov (United States)

Pabinger, Stephan; Rödiger, Stefan; Kriegner, Albert; Vierlinger, Klemens; Weinhäusel, Andreas

2014-09-01

Real-time quantitative polymerase-chain-reaction (qPCR) is a standard technique in most laboratories used for various applications in basic research. Analysis of qPCR data is a crucial part of the entire experiment, which has led to the development of a plethora of methods. The released tools either cover specific parts of the workflow or provide complete analysis solutions. Here, we surveyed 27 open-access software packages and tools for the analysis of qPCR data. The survey includes 8 Microsoft Windows, 5 web-based, 9 R-based and 5 tools from other platforms. Reviewed packages and tools support the analysis of different qPCR applications, such as RNA quantification, DNA methylation, genotyping, identification of copy number variations, and digital PCR. We report an overview of the functionality, features and specific requirements of the individual software tools, such as data exchange formats, availability of a graphical user interface, included procedures for graphical data presentation, and offered statistical methods. In addition, we provide an overview about quantification strategies, and report various applications of qPCR. Our comprehensive survey showed that most tools use their own file format and only a fraction of the currently existing tools support the standardized data exchange format RDML. To allow a more streamlined and comparable analysis of qPCR data, more vendors and tools need to adapt the standardized format to encourage the exchange of data between instrument software, analysis tools, and researchers.

Microbiological and molecular identification of bacterial species isolated from nasal and oropharyngeal mucosa of fuel workers in Riyadh, Saudi Arabia.

Science.gov (United States)

AlWakeel, Suaad S

2017-09-01

This study aimed to determine the bacterial species colonizing the nasal and oropharyngeal mucosa of fuel workers in Central Riyadh, Saudi Arabia on a microbiological and molecular level. Throat and nasal swab samples were obtained from 29 fuel station attendants in the period of time extending from March to May 2014 in Riyadh, Saudi Arabia. Microbiological identification techniques were utilized to identify the bacterial species isolated. Antibiotic sensitivity was assessed for each of the bacterial isolates. Molecular identification techniques based on PCR analysis of specific genomic sequences was conducted and was the basis on which phylogeny representation was done for 10 randomly selected samples of the isolates. Blood was drawn and a complete blood count was conducted to note the hematological indices for each of the study participants. Nineteen bacterial species were isolated from both the nasal cavity and the oropharynx including Streptococcus thoraltensis , alpha-hemolytic streptococci, Staphylococcus hominis , coagulase-negative staphylococci, Leuconostoc mesenteroides , Erysipelothrix rhusiopathiae and several others. We found 100% sensitivity of the isolates to ciprofloxacin, cefuroxime and gentamicin. Whereas cefotaxime and azithromycin posted sensitivities of 85.7% and 91.4%, respectively. Low sensitivities (fuel products may be a contributing factor to bacterial colonization of the respiratory tract in fuel workers.

Kimchi: Spicy Science for the Undergraduate Microbiology Laboratory ?

OpenAIRE

Young, Virginia A.; Kiefer, Adam M.

2014-01-01

Undergraduate microbiology courses offer a perfect opportunity to introduce students to historical food preservation processes that are still in use today. The fermentation of vegetables, as occurs in the preparation of sauerkraut and kimchi, uses an enrichment step to select for the growth of naturally occurring lactic acid bacteria (LAB).  This is an active learning exercise in which students learn a food preparation skill and basic microbiological terms such as selection and enrichment.  W...

[Applications of MALDI-TOF technology in clinical microbiology].

Science.gov (United States)

Suarez, S; Nassif, X; Ferroni, A

2015-02-01

Until now, the identification of micro-organisms has been based on the cultural and biochemical characteristics of bacterial and fungal species. Recently, Mass Spectrometry type Matrix-Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF MS) was developed in clinical microbiology laboratories. This new technology allows identification of micro-organisms directly from colonies of bacteria and fungi within few minutes. In addition, it can be used to identify germs directly from positive blood culture bottles or directly from urine samples. Other ways are being explored to expand the use of MALDI-TOF in clinical microbiology laboratories. Indeed, some studies propose to detect bacterial antibiotic resistance while others compare strains within species for faster strain typing. The main objective of this review is to update data from the recent literature for different applications of MALDI-TOF technique in microbiological diagnostic routine. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Microbiological quality of Argentinian paprika.

Science.gov (United States)

Melo González, María G; Romero, Stella M; Arjona, Mila; Larumbe, Ada G; Vaamonde, Graciela

The aim of this study was to evaluate the microbiological quality of paprika produced in Catamarca, Argentina. Microbiological analyses were carried out for the enumeration of total aerobic mesophilic bacteria, coliforms, yeasts and molds, and the detection of Salmonella in samples obtained from different local producers during three consecutive years. The mycobiota was identified paying special attention to the mycotoxigenic molds. Standard plate counts of aerobic mesophilic bacteria ranged from 2.7×10 5 to 3.7×10 7 CFU/g. Coliform counts ranged from <10 to 8.1×10 4 CFU/g. Salmonella was not detected in any of the samples tested. Fungal counts (including yeasts and molds) ranged between 2×10 2 and 1.9×10 5 CFU/g. These results showed a high level of microbial contamination, exceeding in several samples the maximum limits set in international food regulations. The study of the mycobiota demonstrated that Aspergillus was the predominant genus and Aspergillus niger (potential producer of ochratoxin A) the most frequently isolated species, followed by Aspergillus flavus (potential producer of aflatoxins). Other species of potential toxigenic fungi such as Aspergillus ochraceus, Aspergillus westerdijkiae, Penicillium chrysogenum, Penicillium crustosum, Penicillium commune, Penicillium expansum and Alternaria tenuissima species group were encountered as part of the mycobiota of the paprika samples indicating a risk of mycotoxin contamination. A. westerdijkiae was isolated for the first time in Argentina. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Microbiological Assessment of Commercially Available Quinine ...

African Journals Online (AJOL)

Erah

Key words: Microbiological quality, quinine syrups, water for injection, pyrogen test. Received: 12 February ... pharmaceutical industry is indispensable, especially in ... Production of WFI or any other pharmaceutical products .... culture media.

Changes in the physicochemical and microbiological properties of frozen araça pulp during storage

Directory of Open Access Journals (Sweden)

Clarissa Damiani

2013-02-01

Full Text Available Araça belongs to the Myrtaceae family and is popularly known as araçá-comum, araçá-azedo, or araçá-do-campo. Frozen fruit pulp is of great importance for the food industry, which can produce it at the time of harvest, store it, and use it according to the demand of the consumer market and/or as an ingredient in the formulation of products such as yogurt, candies, and ice creams among others. The aim of this study was to evaluate the physical, chemical, and microbiological stability of frozen araça pulp during 12 months of frozen storage. It was observed that the levels of moisture (90.55-88.75%, ash (0.34-0.26% total soluble sugars (7.11-6.62%, sucrose (3.55-1.39%, soluble pectin (0.24-0.23%, total pectin (0.5-0.46%, pH (3.82-2.31%, organic acids (698.12-122.25 µg.g-1 citric acid, and phenolic compounds (6.22-0.00 mg GAE.100 g-1 decreased during storage, whereas the levels of protein (0.61-0.83%, lipids (0.14-0.38%, total carbohydrates (8.36-9.78%, calorific value (37.14-45.86 kcal.100 g-1, reducing sugars (3.51-5.21%, soluble solids (5.17-6.0%, total antioxidant capacity (6.89-35.13%, and color parameters (L*49.75-50.67; a*0.79-1.82 and b*22.5-25.19 increased over the one-year storage period. According to the chemical and microbiological parameters assessed, the product can be stored for 12 months without loss of quality with addition of citric acid as a preservative.

Application of the MALDI Biotyper to clinical microbiology: progress and potential.

Science.gov (United States)

Kostrzewa, Markus

2018-03-01

The introduction of the MALDI Biotyper in laboratories substantially changed microbiology practice, this has been called a revolution. The system accelerated diagnostic while costs were reduced and accuracy was increased. In just a few years MALDI-TOF MS became the first-line identification tool for microorganisms. Ten years after its introduction, more than 2000 MALDI Biotyper systems are installed in laboratories which are performing routine diagnostic, and the number is still increasing. Areas covered: This article summarises changes in clinical microbiology introduced by the MALDI Biotyper and its effects, as it has been published in peer reviewed articles found in PubMed. Further, the potential of novel developments to increase the value of the system is described. Expert commentary: The MALDI Biotyper has significantly improved clinical microbiology in the area of microorganism identification. Now new developments and applications, e.g. for typing and resistance testing, might further increase its value in clinical microbiology. The systems might get the central diagnostic analyser which is getting integrated into the widely automated microbiology laboratories of the future.

Microbiological Quality Assessment of Game Meats at Retail in Japan.

Science.gov (United States)

Asakura, Hiroshi; Kawase, Jun; Ikeda, Tetsuya; Honda, Mioko; Sasaki, Yoshimasa; Uema, Masashi; Kabeya, Hidenori; Sugiyama, Hiromu; Igimi, Shizunobu; Takai, Shinji

2017-12-01

In this study, we examined the prevalence of Shiga toxin-producing Escherichia coli and Salmonella spp. and the distribution of indicator bacteria in 248 samples of game meats (120 venison and 128 wild boar) retailed between November 2015 and March 2016 in Japan. No Salmonella spp. were detected in any of the samples, whereas Shiga toxin-producing Escherichia coli serotype OUT:H25 (stx 2d + , eae - ) was isolated from one deer meat sample, suggesting a possible source for human infection. Plate count assays indicated greater prevalence of coliforms and E. coli in wild boar meat than in venison, whereas their prevalence in processing facilities showed greater variation than in animal species. The 16S rRNA ion semiconductor sequencing analysis of 24 representative samples revealed that the abundances of Acinetobacter and Arthrobacter spp. significantly correlated with the prevalence of E. coli, and quantitative PCR analyses in combination with selective plate count assay verified these correlations. To our knowledge, this is the first report to characterize the diversity of microorganisms of game meats at retail in Japan, together with identification of dominant microbiota. Our data suggest the necessity of bottom-up hygienic assessment in areas of slaughtering and processing facilities to improve microbiological safety.

Real-time PCR assays for detection of Brucella spp. and the identification of genotype ST27 in bottlenose dolphins (Tursiops truncatus).

Science.gov (United States)

Wu, Qingzhong; McFee, Wayne E; Goldstein, Tracey; Tiller, Rebekah V; Schwacke, Lori

2014-05-01

Rapid detection of Brucella spp. in marine mammals is challenging. Microbiologic culture is used for definitive diagnosis of brucellosis, but is time consuming, has low sensitivity and can be hazardous to laboratory personnel. Serological methods can aid in diagnosis, but may not differentiate prior exposure versus current active infection and may cross-react with unrelated Gram-negative bacteria. This study reports a real-time PCR assay for the detection of Brucella spp. and application to screen clinical samples from bottlenose dolphins stranded along the coast of South Carolina, USA. The assay was found to be 100% sensitive for the Brucella strains tested, and the limit of detection was 0.27fg of genomic DNA from Brucella ceti B1/94 per PCR volume. No amplification was detected for the non-Brucella pathogens tested. Brucella DNA was detected in 31% (55/178) of clinical samples tested. These studies indicate that the real-time PCR assay is highly sensitive and specific for the detection of Brucella spp. in bottlenose dolphins. We also developed a second real-time PCR assay for rapid identification of Brucella ST27, a genotype that is associated with human zoonotic infection. Positive results were obtained for Brucella strains which had been identified as ST27 by multilocus sequence typing. No amplification was found for other Brucella strains included in this study. ST27 was identified in 33% (18/54) of Brucella spp. DNA-positive clinical samples. To our knowledge, this is the first report on the use of a real-time PCR assay for identification of Brucella genotype ST27 in marine mammals. Copyright © 2014 Elsevier B.V. All rights reserved.

Practical issues in implementing whole-genome-sequencing in routine diagnostic microbiology.

Science.gov (United States)

Rossen, J W A; Friedrich, A W; Moran-Gilad, J

2018-04-01

Next generation sequencing (NGS) is increasingly being used in clinical microbiology. Like every new technology adopted in microbiology, the integration of NGS into clinical and routine workflows must be carefully managed. To review the practical aspects of implementing bacterial whole genome sequencing (WGS) in routine diagnostic laboratories. Review of the literature and expert opinion. In this review, we discuss when and how to integrate whole genome sequencing (WGS) in the routine workflow of the clinical laboratory. In addition, as the microbiology laboratories have to adhere to various national and international regulations and criteria for their accreditation, we deliberate on quality control issues for using WGS in microbiology, including the importance of proficiency testing. Furthermore, the current and future place of this technology in the diagnostic hierarchy of microbiology is described as well as the necessity of maintaining backwards compatibility with already established methods. Finally, we speculate on the question of whether WGS can entirely replace routine microbiology in the future and the tension between the fact that most sequencers are designed to process multiple samples in parallel whereas for optimal diagnosis a one-by-one processing of the samples is preferred. Special reference is made to the cost and turnaround time of WGS in diagnostic laboratories. Further development is required to improve the workflow for WGS, in particular to shorten the turnaround time, reduce costs, and streamline downstream data analyses. Only when these processes reach maturity will reliance on WGS for routine patient management and infection control management become feasible, enabling the transformation of clinical microbiology into a genome-based and personalized diagnostic field. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Comparison of kDNA PCR-hybridization assay with three PCR methods for canines visceral Leishmaniasis diagnosis

Energy Technology Data Exchange (ETDEWEB)

Pilatti, Marcia M.; Andrade, Antero S.R. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: marciapilatti@yahoo.com.br, e-mail: antero@cdtn.br; Ferreira, Sidney A. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Parasitologia], e-mail: saninoalmeida@gmail.com

2009-07-01

The sensitivity of the kDNA PCR-Hybridization assay, which uses radioactive DNA probes (labeled with {sup 32}P), was compared with three conventional PCR methods used for canine visceral leishmaniasis diagnosis. All PCR methods had two steps: a first amplification followed by hybridization or by a new amplification (nested or semi nested). Two methods (kDNA PCR-Hybridization and kDNA snPCR) used primers addressed to kinetoplast minicircles and the other two methods to the coding (LnPCR) and intergenic noncoding regions (ITS-1 nPCR) of the ribosomal rRNA genes. The comparison was accomplished in two groups of 23 infected dogs using samples collected by the conjunctival swab procedure. In the Group 1 the DNA was extracted from cotton swabs by phenol-chloroform and in Group 2 by boiling. The most efficient PCR methods in the Group 1 were those based on kDNA targets. The kDNA PCR-Hybridization was able to detect parasites in 22/23 dogs (95.6%) and in 40/46 samples (86.9%). The kDNA snPCR was positive for 21/23 dogs (91.3%) and for 40/46 samples (86.9%). The positivities of the kDNA based methods were significantly higher than the positivities verified for the methods based on ribosomal rRNA genes (p<0.05). In the Group 2 the kDNA PCR- Hybridization showed a better performance detecting parasites in 18/23 dogs (78.3%) and in 31/46 samples (67.4%), significantly higher than the other three methods (p<0.05). The higher sensitivity of the minicircle kDNA based assays reported by others was confirmed in this study and kDNA PCR-Hybridization showed the best sensitivity among the assays evaluated. (author)

Comparison of kDNA PCR-hybridization assay with three PCR methods for canines visceral Leishmaniasis diagnosis

International Nuclear Information System (INIS)

Pilatti, Marcia M.; Andrade, Antero S.R.; Ferreira, Sidney A.

2009-01-01

The sensitivity of the kDNA PCR-Hybridization assay, which uses radioactive DNA probes (labeled with 32 P), was compared with three conventional PCR methods used for canine visceral leishmaniasis diagnosis. All PCR methods had two steps: a first amplification followed by hybridization or by a new amplification (nested or semi nested). Two methods (kDNA PCR-Hybridization and kDNA snPCR) used primers addressed to kinetoplast minicircles and the other two methods to the coding (LnPCR) and intergenic noncoding regions (ITS-1 nPCR) of the ribosomal rRNA genes. The comparison was accomplished in two groups of 23 infected dogs using samples collected by the conjunctival swab procedure. In the Group 1 the DNA was extracted from cotton swabs by phenol-chloroform and in Group 2 by boiling. The most efficient PCR methods in the Group 1 were those based on kDNA targets. The kDNA PCR-Hybridization was able to detect parasites in 22/23 dogs (95.6%) and in 40/46 samples (86.9%). The kDNA snPCR was positive for 21/23 dogs (91.3%) and for 40/46 samples (86.9%). The positivities of the kDNA based methods were significantly higher than the positivities verified for the methods based on ribosomal rRNA genes (p<0.05). In the Group 2 the kDNA PCR- Hybridization showed a better performance detecting parasites in 18/23 dogs (78.3%) and in 31/46 samples (67.4%), significantly higher than the other three methods (p<0.05). The higher sensitivity of the minicircle kDNA based assays reported by others was confirmed in this study and kDNA PCR-Hybridization showed the best sensitivity among the assays evaluated. (author)

[Bibliometric analysis of the Spanish scientific production in Infectious Diseases and Microbiology].

Science.gov (United States)

Ramos, José Manuel; González-Alcaide, Gregorio; Gutiérrez, Félix

2016-03-01

The bibliometric analysis of production and impact of documents by knowledge area is a quantitative and qualitative indicator of research activity in this field. The aim of this article is to determine the contribution of Spanish research institutions in Infectious Diseases and Microbiology in recent years. Documents published in the journals included in the categories "Infectious Diseases" and "Microbiology" of the Web of Science (Science Citation Index Expanded) of the ISI Web of Knowledge from the year 2000-2013 were analysed. In Infectious Diseases, Spain ranked fourth worldwide, and contributed 5.7% of the 233,771 documents published in this specialty. In Microbiology, Spain was in sixth place with a production rate of 5.8% of the 149,269 documents of this category. The Spanish production increased over the study period, both in Infectious Diseases and Microbiology, from 325 and 619 documents in 2000 to 756 and 1245 documents in 2013, with a growth rate of 131% and 45.8%, respectively. The journal with the largest number of documents published was Enfermedades Infecciosas y Microbiología Clínica, with 8.6% and 8.2% of papers published in the categories of Infectious Diseases and Microbiology, respectively, and was the result of international collaborations, especially with institutions in the United States. The "index h" was 116 and 139 in Infectious Diseases and Microbiology, placing Spain in fifth place in both categories within countries of the European Union. In recent years, Spanish research in Infectious Diseases and Microbiology has reached a good level of production and international visibility, reaching a global leadership position. Copyright © 2015. Published by Elsevier España, S.L.U.

A propidium monoazide–quantitative PCR method for the detection and quantification of viable Enterococcus faecalis in large-volume samples of marine waters

KAUST Repository

Salam, Khaled W.; El-Fadel, Mutasem E.; Barbour, Elie K.; Saikaly, Pascal

2014-01-01

The development of rapid detection assays of cell viability is essential for monitoring the microbiological quality of water systems. Coupling propidium monoazide with quantitative PCR (PMA-qPCR) has been successfully applied in different studies for the detection and quantification of viable cells in small-volume samples (0.25-1.00 mL), but it has not been evaluated sufficiently in marine environments or in large-volume samples. In this study, we successfully integrated blue light-emitting diodes for photoactivating PMA and membrane filtration into the PMA-qPCR assay for the rapid detection and quantification of viable Enterococcus faecalis cells in 10-mL samples of marine waters. The assay was optimized in phosphate-buffered saline and seawater, reducing the qPCR signal of heat-killed E. faecalis cells by 4 log10 and 3 log10 units, respectively. Results suggest that high total dissolved solid concentration (32 g/L) in seawater can reduce PMA activity. Optimal PMA-qPCR standard curves with a 6-log dynamic range and detection limit of 102 cells/mL were generated for quantifying viable E. faecalis cells in marine waters. The developed assay was compared with the standard membrane filter (MF) method by quantifying viable E. faecalis cells in seawater samples exposed to solar radiation. The results of the developed PMA-qPCR assay did not match that of the standard MF method. This difference in the results reflects the different physiological states of E. faecalis cells in seawater. In conclusion, the developed assay is a rapid (∼5 h) method for the quantification of viable E. faecalis cells in marine recreational waters, which should be further improved and tested in different seawater settings. © 2014 Springer-Verlag Berlin Heidelberg.