scholarly journals Development of Immunochromatography-Based Methods for Detection of Leptospiral Lipopolysaccharide Antigen in Urine

2013 ◽  
Vol 20 (5) ◽  
pp. 683-690 ◽  
Author(s):  
Dian Widiyanti ◽  
Nobuo Koizumi ◽  
Takashi Fukui ◽  
Lisa T. Muslich ◽  
Takaya Segawa ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Urine Samples ◽  
Bacterial Cells ◽  
Diagnostic Assay ◽  
Healthy Individuals ◽  
Content Type ◽  
Diagnostic Assays ◽  
The World ◽  
Further Development ◽  
Study Application

ABSTRACTLeptospirosis is an infectious disease caused by the spirochete bacteriaLeptospiraspp. and is commonly found throughout the world. Diagnosis of leptospirosis performed by culture and microscopic agglutination tests is laborious and time-consuming. Therefore, we aimed to develop a novel immunochromatography (ICG)-based method for detectingLeptospiraantigen in the urine of patients and animals. We used the 1H6 monoclonal antibody (MAb), which is specific to the lipopolysaccharide (LPS) that is common amongLeptospiraspp. The MAb was coupled to 40-nm-diameter colloidal gold, and the amounts of labeled antibody and immobilized antibody were 23 μg and 2 μg per test, respectively. Several strains ofLeptospiraand other bacterial species were used to evaluate the sensitivities and specificities of the assays we developed. The detection limit of the assays was 106cells/ml when disrupted whole bacterial cells were used. The assays wereLeptospiraspecific since they did not cross-react with non-Leptospirabacteria used in the study. Application of diagnostic assays was done on the urine samples of 46Leptospira-infected hamsters, 44 patients with suspected leptospirosis, and 14 healthy individuals. Pretreatment of the urine samples by boiling and centrifugation (for ultrafiltration and concentration) eliminated nonspecific reactions that occurred in the assay. The sensitivity and specificity of the ICG-based lateral flow assay (LFA) were 89% and 87%, respectively, which were higher than those of the dipstick assay, which were 80% and 74%, respectively. In summary, this ICG-based LFA can be used as an alternative diagnostic assay for leptospirosis. Further development is still necessary to improve the assay.

scholarly journals A Stringent Analysis of Polyphosphate Dynamics inEscherichia coli

2019 ◽  
Vol 201 (9) ◽  
Author(s):  
Michael Downey
Keyword(s):  
Escherichia Coli ◽  
Infection Control ◽  
Bacterial Species ◽  
Stringent Response ◽  
Industrial Applications ◽  
Bacterial Cells ◽  
Inescherichia Coli ◽  
Content Type ◽  
Polyphosphate Accumulation ◽  
Inorganic Phosphates

ABSTRACTDuring stress, bacterial cells activate a conserved pathway called the stringent response that promotes survival. Polyphosphates are long chains of inorganic phosphates that modulate this response in diverse bacterial species. In this issue, Michael J. Gray provides an important correction to the model of how polyphosphate accumulation is regulated during the stringent response inEscherichia coli(M. J. Gray, J. Bacteriol, 201:e00664-18, 2019,https://doi.org/10.1128/JB.00664-18). With other recent publications, this study provides a revised framework for understanding how bacterial polyphosphate dynamics might be exploited in infection control and industrial applications.

scholarly journals Genomics of the Uncultivated, Periodontitis-Associated BacteriumTannerellasp. BU045 (Oral Taxon 808)

mSystems ◽  
2018 ◽  
Vol 3 (3) ◽  
Author(s):  
Clifford J. Beall ◽  
Alisha G. Campbell ◽  
Ann L. Griffen ◽  
Mircea Podar ◽  
Eugene J. Leys
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Chronic Periodontitis ◽  
Bacterial Species ◽  
The United States ◽  
Oral Microbiome ◽  
Rrna Gene ◽  
Bacterial Cells ◽  
Data Set ◽  
Content Type

ABSTRACTDespite decades of research into the human oral microbiome, many species remain uncultivated. The technique of single-cell whole-genome amplification and sequencing provides a means of deriving genome sequences for species that can be informative on biological function and suggest pathways to cultivation.Tannerella forsythiahas long been known to be highly associated with chronic periodontitis and to cause periodontitis-like symptoms in experimental animals, andTannerellasp. BU045 (human oral taxon 808) is an uncultivated relative of this organism. In this work, we extend our previous sequencing of theTannerellasp. BU063 (human oral taxon 286) genome by sequencing amplified genomes from 11 cells ofTannerellasp. BU045, including 3 genomes that are at least 90% complete.Tannerellasp. BU045 is more closely related toTannerellasp. BU063 than toT. forsythiaby gene content and average nucleotide identity. However, two independent data sets of association with periodontitis, one based on 16S rRNA gene abundance and the other based on gene expression in a metatranscriptomic data set, show thatTannerellasp. BU045 is more highly associated with disease thanTannerellasp. BU063. Comparative genomics shows genes and functions that are shared or unique to the different species, which may direct further research of the pathogenesis of chronic periodontitis.IMPORTANCEPeriodontitis (gum disease) affects 47% of adults over 30 in the United States (P. I. Eke, B. A. Dye, L. Wei, G. O. Thornton-Evans, R. J. Genco, et al., J Dent Res 91:914–920, 2012), and it cost between $39 and $396 billion worldwide in 2015 (A. J. Righolt, M. Jevdjevic, W. Marcenes, and S. Listl, J Dent Res, 17 January 2018, https://doi.org/10.1177/0022034517750572). Many bacteria associated with the disease are known only by the DNA sequence of their 16S rRNA gene. In this publication, amplification and sequencing of DNA from single bacterial cells are used to obtain nearly complete genomes ofTannerellasp. BU045, a species of bacteria that is more prevalent in patients with periodontitis than in healthy patients. Comparing the complete genome of this bacterium to genomes of related bacterial species will help to better understand periodontitis and may help to grow this organism in pure culture, which would allow a better understanding of its role in the mouth.

scholarly journals Target-Specific Assay for Rapid and Quantitative Detection of Mycobacterium chimaera DNA

2017 ◽  
Vol 55 (6) ◽  
pp. 1847-1856 ◽  
Author(s):  
Enrique Zozaya-Valdés ◽  
Jessica L. Porter ◽  
John Coventry ◽  
Janet A. M. Fyfe ◽  
Glen P. Carter ◽  
...  
Keyword(s):  
In Silico ◽  
Bacterial Species ◽  
Invasive Disease ◽  
Diagnostic Methods ◽  
Quantitative Detection ◽  
Content Type ◽  
Diagnostic Assays ◽  
Mycobacterial Genome ◽  
Increased Sensitivity

ABSTRACT Mycobacterium chimaera is an opportunistic environmental mycobacterium belonging to the Mycobacterium avium - M. intracellulare complex. Although most commonly associated with pulmonary disease, there has been growing awareness of invasive M. chimaera infections following cardiac surgery. Investigations suggest worldwide spread of a specific M. chimaera clone, associated with contaminated hospital heater-cooler units used during the surgery. Given the global dissemination of this clone, its potential to cause invasive disease, and the laboriousness of current culture-based diagnostic methods, there is a pressing need to develop rapid and accurate diagnostic assays specific for M. chimaera . Here, we assessed 354 mycobacterial genome sequences and confirmed that M. chimaera is a phylogenetically coherent group. In silico comparisons indicated six DNA regions present only in M. chimaera . We targeted one of these regions and developed a TaqMan quantitative PCR (qPCR) assay for M. chimaera with a detection limit of 100 CFU/ml in whole blood spiked with bacteria. In vitro screening against DNA extracted from 40 other mycobacterial species and 22 bacterial species from 21 diverse genera confirmed the in silico -predicted specificity for M. chimaera . Screening 33 water samples from heater-cooler units with this assay highlighted the increased sensitivity of PCR compared to culture, with 15 of 23 culture-negative samples positive by M. chimaera qPCR. We have thus developed a robust molecular assay that can be readily and rapidly deployed to screen clinical and environmental specimens for M. chimaera .

scholarly journals Contributions ofCandida albicansDimorphism, Adhesive Interactions, and Extracellular Matrix to the Formation of Dual-Species Biofilms withStreptococcus gordonii

mBio ◽  
2019 ◽  
Vol 10 (3) ◽  
Author(s):  
Daniel Montelongo-Jauregui ◽  
Stephen P. Saville ◽  
Jose L. Lopez-Ribot
Keyword(s):  
Extracellular Matrix ◽  
Oral Cavity ◽  
Bacterial Species ◽  
Fungal Species ◽  
Bacterial Cells ◽  
Mixed Species ◽  
Bacterial Populations ◽  
Content Type ◽  
Mutant Strains ◽  
Adhesive Interactions

ABSTRACTFungal and bacterial populations coexist in the oral cavity, frequently forming mixed-species biofilms that complicate treatment against polymicrobial infections. However, despite relevance to oral health, the bidirectional interactions between these microbial populations are poorly understood. In this study, we aimed to elucidate the mechanisms underlying the interactions between the fungal speciesCandida albicansand the bacterial speciesStreptococcus gordoniias they coexist in mixed-species biofilms. Specifically, the interactions of differentC. albicansmutant strains deficient in filamentation (efg1Δ/Δ andbrg1Δ/Δ), adhesive interactions (als3Δ/Δ andbcr1Δ/Δ), and production of matrix exopolymeric substances (EPS) (kre5Δ/Δ, mnn9Δ/Δ,rlm1Δ/Δ, andzap1Δ/Δ) were evaluated withS. gordoniiunder different conditions mimicking the environment in the oral cavity. Interestingly, our results revealed that growth of the biofilm-deficientC. albicansals3Δ/Δandbcr1Δ/Δmutant strains in synthetic saliva or withS. gordoniirestored their biofilm-forming ability. Moreover, challenging previous observations indicating an important role of morphogenetic conversions in the interactions between these two species, our results indicated a highly synergistic interaction betweenS. gordoniiand theC. albicansfilamentation-deficientefg1Δ/Δandbrg1Δ/Δdeletion mutants, which was particularly noticeable when the mixed biofilms were grown in synthetic saliva. Importantly, dual-species biofilms were found to exhibit increase in antimicrobial resistance, indicating that components of the fungal exopolymeric material confer protection to streptococcal cells against antibacterial treatment. Collectively, these findings unravel a high degree of complexity in the interactions betweenC. albicansandS. gordoniiin mixed-species biofilms, which may impact homeostasis in the oral cavity.IMPORTANCEMicrobial communities have a great impact in health and disease.C. albicansinteracts with multiple microorganisms in the oral cavity, frequently forming polymicrobial biofilms. We report on the synergistic interactions betweenC. albicansand the Gram-positive bacteriumS. gordonii, for which we have examined the different contributions of adhesive interactions, filamentation, and the extracellular matrix to the formation of dual-species biofilms. Our results demonstrate that growth in the presence of the bacterium can restore the biofilm-forming ability of differentC. albicansmutant strains with defects in adhesion and filamentation. The mixed-species biofilms also show high levels of resistance to antibacterial and antifungal antibiotics, and our results indicate that the fungal biofilm matrix protects bacterial cells within these mixed-species biofilms. Our observations add to a growing body of evidence indicating a high level of complexity in the reciprocal interactions and consortial behavior of fungal/bacterial biofilms.

scholarly journals RNA–Stable-Isotope Probing Shows Utilization of Carbon from Inulin by Specific Bacterial Populations in the Rat Large Bowel

2014 ◽  
Vol 80 (7) ◽  
pp. 2240-2247 ◽  
Author(s):  
Gerald W. Tannock ◽  
Blair Lawley ◽  
Karen Munro ◽  
Ian M. Sims ◽  
Julian Lee ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Bacterial Species ◽  
Buoyant Density ◽  
Stable Isotope Probing ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Bacterial Cells ◽  
Bacterial Populations ◽  
Content Type ◽  
And Function

ABSTRACTKnowledge of the trophisms that underpin bowel microbiota composition is required in order to understand its complex phylogeny and function. Stable-isotope (13C)-labeled inulin was added to the diet of rats on a single occasion in order to detect utilization of inulin-derived substrates by particular members of the cecal microbiota. Cecal digesta from Fibruline-inulin-fed rats was collected prior to (0 h) and at 6, 12, 18 and 24 h following provision of the [13C]inulin diet. RNA was extracted from these cecal specimens and fractionated in isopycnic buoyant density gradients in order to detect13C-labeled nucleic acid originating in bacterial cells that had metabolized the labeled dietary constituent. RNA extracted from specimens collected after provision of the labeled diet was more dense than 0-h RNA. Sequencing of 16S rRNA genes amplified from cDNA obtained from these fractions showed thatBacteroides uniformis,Blautia glucerasea,Clostridium indolis, andBifidobacterium animaliswere the main users of the13C-labeled substrate. Culture-based studies of strains of these bacterial species enabled trophisms associated with inulin and its hydrolysis products to be identified.B. uniformisutilized Fibruline-inulin for growth, whereas the other species used fructo-oligosaccharide and monosaccharides. Thus, RNA–stable-isotope probing (RNA-SIP) provided new information about the use of carbon from inulin in microbiota metabolism.

Saving the Overlooked Continent. American Protestant Missions in Western Europe 1940-1975 Hans Krabbendam

2021 ◽  
Vol 30 (1) ◽  
pp. 237-240
Author(s):  
Frank Hinkelmann
Keyword(s):  
North America ◽  
Western Europe ◽  
World Council Of Churches ◽  
Content Type ◽  
American Interest ◽  
P Content ◽  
The World ◽  
World Council ◽  
History Of ◽  
Further Development

<p content-type="flush left">Summary <p content-type="flush left">This book presents research into North-American evangelical missionary initiatives in Europe between 1940 and 1975. It investigates the motives and aims of the American interest in Europe and describes the further development of the American-European relationship among evangelicals. Regarding the first decades, the author deals with the competition within the conservative American camp between traditional fundamentalists and evangelicals for influence in Europe (which the fundamentalists lost) and contrasts developments in the evangelical space with those of traditional inter-church relations in the context of the World Council of Churches between North America and Europe. Krabbendam makes an important contribution to the history of the evangelical movement in Europe and the influence of North America. <p content-type="flush left">Zusammenfassung <p content-type="flush left">Dieses Buch präsentiert nordamerikanische evangelikale Missionsinitiativen in Europa in den Jahren zwischen 1940 und 1975. Es erarbeitet Motive und Ziele des amerikanischen Missionsinteresses an Europa und schildert die verschiedenen Phasen der weiteren Entwicklung des amerikanisch-europäischen Verhältnisses unter Evangelikalen. Dabei geht der Autor hinsichtlich der ersten Jahrzehnte auf den Wettstreit innerhalb des konservativen US-amerikanischen Lagers zwischen traditionellen Fundamentalisten und Evangelikalen um Einfluss in Europa ein (den das fundamentalistische Lager verlor) und stellt die Entwicklungen im evangelikalen Raum denen traditioneller zwischenkirchlicher Beziehungen im Umfeld des Weltkirchenrates zwischen Nordamerika und Europa gegenüber. Krabbendam legt einen wichtigen Beitrag zur Geschichte der evangelikalen Bewegung in Europa und des Einflusses Nordamerikas in diesen Jahrzehnten vor. <p content-type="flush left">Résumé <p content-type="flush left">Ce livre traite des initiatives missionnaires évangéliques nord-américaines en Europe entre 1940 et 1975. Il examine les motifs et les objectifs de l’intérêt américain pour l’Europe et décrit le développement de la relation américano-européenne dans la sphère évangélique. S’intéressant aux premières décennies, l’auteur étudie la compétition opposant, au sein même du camp américain conservateur, fondamentalistes traditionnels et évangéliques pour le gain d’une influence prépondérante en Europe (compétition perdue par les fondamentalistes) et compare les développements perceptibles dans l’espace évangélique à ceux des relations inter-Églises traditionnelles dans le cadre du Conseil Œcuménique des Églises entre l’Amérique et l’Europe. Krabbendam apporte une contribution importante à l’histoire du mouvement évangélique en Europe et de l’influence nord-américaine.

scholarly journals Novel Genus of Phages Infecting Streptococcus thermophilus: Genomic and Morphological Characterization

2020 ◽  
Vol 86 (13) ◽  
Author(s):  
Cécile Philippe ◽  
Sébastien Levesque ◽  
Moïra B. Dion ◽  
Denise M. Tremblay ◽  
Philippe Horvath ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Streptococcus Thermophilus ◽  
Morphological Characterization ◽  
Open Reading Frames ◽  
Comparative Genomic ◽  
Bacterial Cells ◽  
Content Type ◽  
Milk Fermentation ◽  
Recent Emergence ◽  
Surveillance Programs

ABSTRACT Streptococcus thermophilus is a lactic acid bacterium commonly used for the manufacture of yogurt and specialty cheeses. Virulent phages represent a major risk for milk fermentation processes worldwide, as they can inactivate the added starter bacterial cells, leading to low-quality fermented dairy products. To date, four genetically distinct groups of phages infecting S. thermophilus have been described. Here, we describe a fifth group. Phages P738 and D4446 are virulent siphophages that infect a few industrial strains of S. thermophilus. The genomes of phages P738 and D4446 were sequenced and found to contain 34,037 and 33,656 bp as well as 48 and 46 open reading frames, respectively. Comparative genomic analyses revealed that the two phages are closely related to each other but display very limited similarities to other S. thermophilus phages. In fact, these two novel S. thermophilus phages share similarities with streptococcal phages of nondairy origin, suggesting that they emerged recently in the dairy environment. IMPORTANCE Despite decades of research and adapted antiphage strategies such as CRISPR-Cas systems, virulent phages are still a persistent risk for the milk fermentation industry worldwide, as they can cause manufacturing failures and alter product quality. Phages P738 and D4446 are novel virulent phages that infect the food-grade Gram-positive bacterial species Streptococcus thermophilus. These two related viruses represent a fifth group of S. thermophilus phages, as they are significantly distinct from other known S. thermophilus phages. Both phages share similarities with phages infecting nondairy streptococci, suggesting their recent emergence and probable coexistence in dairy environments. These findings highlight the necessity of phage surveillance programs as the phage population evolves in response to the application of antiphage strategies.

scholarly journals Catalase Expression Is Modulated by Vancomycin and Ciprofloxacin and Influences the Formation of Free Radicals in Staphylococcus aureus Cultures

2015 ◽  
Vol 81 (18) ◽  
pp. 6393-6398 ◽  
Author(s):  
Ying Wang ◽  
Anni B. Hougaard ◽  
Wilhelm Paulander ◽  
Leif H. Skibsted ◽  
Hanne Ingmer ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Staphylococcus Aureus ◽  
Free Radicals ◽  
Hydroxyl Radical ◽  
Hydroxyl Radicals ◽  
Bacterial Species ◽  
Iron Chelation ◽  
Radical Formation ◽  
Bacterial Cells ◽  
Content Type

ABSTRACTDetection of free radicals in biological systems is challenging due to their short half-lives. We have applied electron spin resonance (ESR) spectroscopy combined with spin traps using the probes PBN (N-tert-butyl-α-phenylnitrone) and DMPO (5,5-dimethyl-1-pyrrolineN-oxide) to assess free radical formation in the human pathogenStaphylococcus aureustreated with a bactericidal antibiotic, vancomycin or ciprofloxacin. While we were unable to detect ESR signals in bacterial cells, hydroxyl radicals were observed in the supernatant of bacterial cell cultures. Surprisingly, the strongest signal was detected in broth medium without bacterial cells present and it was mitigated by iron chelation or by addition of catalase, which catalyzes the decomposition of hydrogen peroxide to water and oxygen. This suggests that the signal originates from hydroxyl radicals formed by the Fenton reaction, in which iron is oxidized by hydrogen peroxide. Previously, hydroxyl radicals have been proposed to be generated within bacterial cells in response to bactericidal antibiotics. We found that whenS. aureuswas exposed to vancomycin or ciprofloxacin, hydroxyl radical formation in the broth was indeed increased compared to the level seen with untreated bacterial cells. However,S. aureuscells express catalase, and the antibiotic-mediated increase in hydroxyl radical formation was correlated with reducedkatAexpression and catalase activity in the presence of either antibiotic. Therefore, our results show that inS. aureus, bactericidal antibiotics modulate catalase expression, which in turn influences the formation of free radicals in the surrounding broth medium. If similar regulation is found in other bacterial species, it might explain why bactericidal antibiotics are perceived as inducing formation of free radicals.

scholarly journals Identification and Characterization of a Putative Manganese Export Protein in Vibrio cholerae

2016 ◽  
Vol 198 (20) ◽  
pp. 2810-2817 ◽  
Author(s):  
Carolyn R. Fisher ◽  
Elizabeth E. Wyckoff ◽  
Eric D. Peng ◽  
Shelley M. Payne
Keyword(s):  
Vibrio Cholerae ◽  
Bacterial Species ◽  
Fold Increase ◽  
Bacterial Cells ◽  
Intracellular Iron ◽  
Content Type ◽  
E Coli ◽  
Import And Export ◽  
Export Protein

ABSTRACTManganese plays an important role in the cellular physiology and metabolism of bacterial species, including the human pathogenVibrio cholerae. The intracellular level of manganese ions is controlled through coordinated regulation of the import and export of this element. We have identified a putative manganese exporter (VC0022), namedmneA(manganeseexporterA), which is highly conserved amongVibriospp. AnmneAmutant exhibited sensitivity to manganese but not to other cations. Under high-manganese conditions, themneAmutant showed an almost 50-fold increase in intracellular manganese levels and reduced intracellular iron relative to those of its wild-type parent, suggesting that the mutant's manganese sensitivity is due to the accumulation of toxic levels of manganese and reduced iron. Expression ofmneAsuppressed the manganese-sensitive phenotype of anEscherichia colistrain carrying a mutation in the nonhomologous manganese export gene,mntP, further supporting a manganese export function forV. choleraeMneA. The level ofmneAmRNA was induced approximately 2.5-fold after addition of manganese to the medium, indicating regulation of this gene by manganese. This study offers the first insights into understanding manganese homeostasis in this important pathogen.IMPORTANCEBacterial cells control intracellular metal concentrations by coordinating acquisition in metal-limited environments with export in metal-excess environments. We identified a putative manganese export protein, MneA, inVibrio cholerae. AnmneAmutant was sensitive to manganese, and this effect was specific to manganese. ThemneAmutant accumulated high levels of intracellular manganese with a concomitant decrease in intracellular iron levels when grown in manganese-supplemented medium. Expression ofmneAintranssuppressed the manganese sensitivity of anE. coli mntPmutant. This study is the first to investigate manganese export inV. cholerae.

Glembotskaya G.T., Eremin S.Yu. Scientific and practical approach to optimizing costs on development and promotion of drugs

2019 ◽  
Vol 2019 (3) ◽  
pp. 47-53
Author(s):  
Галина Глембоцкая ◽  
Galina Glembockaya ◽  
Станислав Еремин ◽  
Stanislav Eremin
Keyword(s):  
Scientific Literature ◽  
Pharmacological Action ◽  
Pharmaceutical Market ◽  
Pharmaceutical Companies ◽  
Strategic Development ◽  
The World ◽  
The Russian Federation ◽  
The Cost ◽  
Further Development ◽  
Registration Phase

In order to identify promising strategic development possibilities for the pharmaceutical industry in the Russian Federation, a pilot study was conducted, which has analyzed the main trends in the development of innovative medicines. As a result of the content analysis of available sources of scientific literature, the characteristics of options used in the world practice for increasing the innovative activity of individual subjects and the pharmaceutical market as a whole are presented. Possible reserves for the further development of the innovative component of the pharmaceutical market within the framework of the concept of personalized medicine according to the P4 principle (predictive - personalized - preventive - participatory) are identified and structured. The results of use by individual pharmaceutical companies of scientifically and practically justified approaches to optimizing the costs of development and promoting drugs are presented. The advantages and real prospects of a generally accepted method to reduce the cost of development by «expanding the pharmacological effect» (label expansion) of already existing drugs with a known safety profile in the world practice are shown. A scientific generalization and structuring of the goals and results of the post-registration phase of clinical trials to expand the pharmacological action of a number of drugs already existed at the market have been carried out.

Sign in / Sign up

Export Citation Format

Share Document