Informational characteristics of microbial biofilms formed by clinical strains of Klebsiella pneumoniae in vitro on the surface of the cover glass

Purpose Obtaining quantitative and informational characteristics of biofilms formed by clinical strains of Klebsiella pneumoniae in vitro on the surface of a cover glass. Materials and methods In vitro biofilm formation on the surface of the cover glass was studied for clinical Klebsiella pneumoniae strains, isolated in a monoculture (ESBL +) (n = 3) and in associations with Staphylococcus aureus (n = 6) in 9 patients with chronic osteomyelitis of long bones harvrested from fistulae in the preoperative period or from the infection focus during surgery. Results Monocultures of K. pneumoniae (BLRS +) differed by their lower adhesive ability when compared to strains of K. pneumoniae isolated from associations with S. aureus. The highest adhesive activity on the surface of the cover glass was observed in a mixed culture of K. pneumoniae + S. aureus. Informational characteristics depended on the type of biofilms formed. Common to biofilms was the absence of changes in the maximum possible structural diversity. Significant differences between the existing structural diversity of biofilms formed by monocultures of K. pneumonia, K. pneumonia isolated from associations and a mixed culture of K. pneumoniae + S. aureus were noted. Conclusion The absence of pronounced variability of information indicators during the experiment within each microbial community indicates the tendecy of all systems of emerging biofilms to preserve stabilit

Comprehensive global genome dynamics of Chlamydia trachomatis show ancient diversification followed by contemporary mixing and recent lineage expansion.

Chlamydia trachomatis is the world's most prevalent bacterial sexually transmitted infection and leading infectious cause of blindness, yet it is one of the least understood human pathogens, in part due to the difficulties of in vitro culturing and the lack of available tools for genetic manipulation. Genome sequencing has reinvigorated this field, shedding light on the contemporary history of this pathogen. Here, we analyze 563 full genomes, 455 of which are novel, to show that the history of the species comprises two phases, and conclude that the currently circulating lineages are the result of evolution in different genomic ecotypes. Temporal analysis indicates these lineages have recently expanded in the space of thousands of years, rather than the millions of years as previously thought, a finding that dramatically changes our understanding of this pathogen's history. Finally, at a time when almost every pathogen is becoming increasingly resistant to antimicrobials, we show that there is no evidence of circulating genomic resistance in C. trachomatis

Analysis of the qualitative and quantitative community composition of bacteria isolated from the purulent focus in patients with chronic osteomyelitis over a three year period

Introduction Annual microbiological monitoring of the leading causative agents of osteomyelitis and their antibiotic sensitivity is essential for identifying drugs that have lost the effectiveness. An increase in microbial associations requires different approaches to antibiotic therapy. Analysis of the composition of associations with a priority pathogen to be identified to avoid administration of ineffective drugs and optimize treatment. The purpose was to monitor qualitative and quantitative community composition of microorganisms isolated from the osteomyelitic focus in patients with chronic osteomyelitis over a three-year period. Material and methods The object of the study were strains of gram-negative and gram-positive bacteria isolated during primary inoculation as part of associations of bacteria from wounds and fistulas of patients who were treated in the clinic of infection osteology at the Kurgan Ilizarov Centre between 2018 and 2020. Standard bacteriological methods were used to isolate pure cultures. Bacteria were identified using bacteriological analyzer. Results and discussion Two-component microbial associations isolated in patients with chronic osteomyelitis included P. aeruginosa + S. aureus, Enterobacteriacae + S. aureus, S. aureus + CoNS. The strains of S. aureus and P. aeruginosa were most common pathogens identified in mixed cultures. Inoculations of S. aureus + Enterococcus sp. increased and P. aeruginosa + Enterococcus sp. associations showed a two-fold decrease in 2020 compared to 2018. Three- and four-component associations of bacteria increased with the spectrum of combinations being diverse among the isolated mix cultures over a three-year period. Bacteria of the Enterobacteriacae and S. aureus family were most common in three-component associations. Four-component associations were represented by mix cultures of gram-positive and gram-negative bacteria including NFGOB and S. aureus. Conclusion An increased frequency of isolated microbial associations necessitates an annual analysis of changes in the qualitative and quantitative composition to identify the spectrum of the most common microflora of the osteomyelitic focus and correct antibiotic therapy

Pooling samples : the key to sensitive, specific and cost-effective genetic diagnosis of Chlamydia trachomatis in low-resource countries

The aims of this study were to compare the performance characteristics and cost-effectiveness of pooling endocervical samples for screening and diagnosis of Chlamydia trachomatis, and to investigate the prevalence of C. trachomatis infection in women in Leningrad Oblast, Russia. A total of 1500 endocervical samples were tested individually and when pooled in groups of 5 and 10 samples, respectively. A previously evaluated in-house diagnostic polymerase chain reaction (PCR) assay was utilized. The sensitivity and specificity of the PCR were not affected by either pooling strategy. The estimated prevalence of genital C. trachomatis infection was 6.6%, 6.1% and 6.0% based on individually tested samples, and pools of 5 and 10, respectively. For diagnosis of individual samples, the pooling strategies resulted in cost savings of 53.3% (5 samples per pool) and 44.0% (10 samples per pool). Pooling samples for PCR detection of C. trachomatis is an accurate and cost-saving approach for diagnosis and large-scale prevalence studies in St Petersburg, Russia

Pooling samples : the key to sensitive, specific and cost-effective genetic diagnosis of Chlamydia trachomatis in low-resource countries

The aims of this study were to compare the performance characteristics and cost-effectiveness of pooling endocervical samples for screening and diagnosis of Chlamydia trachomatis, and to investigate the prevalence of C. trachomatis infection in women in Leningrad Oblast, Russia. A total of 1500 endocervical samples were tested individually and when pooled in groups of 5 and 10 samples, respectively. A previously evaluated in-house diagnostic polymerase chain reaction (PCR) assay was utilized. The sensitivity and specificity of the PCR were not affected by either pooling strategy. The estimated prevalence of genital C. trachomatis infection was 6.6%, 6.1% and 6.0% based on individually tested samples, and pools of 5 and 10, respectively. For diagnosis of individual samples, the pooling strategies resulted in cost savings of 53.3% (5 samples per pool) and 44.0% (10 samples per pool). Pooling samples for PCR detection of C. trachomatis is an accurate and cost-saving approach for diagnosis and large-scale prevalence studies in St Petersburg, Russia

Composition of the Vaginal Microbiota in Women of Reproductive Age - Sensitive and Specific Molecular Diagnosis of Bacterial Vaginosis Is Possible?

Background and Objective: Bacterial vaginosis (BV) is the most common vaginal disorder, characterized by depletion of the normal lactobacillus-dominant microbiota and overgrowth of commensal anaerobic bacteria. This study aimed to investigate the composition of the vaginal microbiota in women of reproductive age (healthy women and women with BV), with the view of developing molecular criteria for BV diagnosis. Materials and Methods: Vaginal samples from 163 women (79 control, 73 BV and 11 intermediate (Lactobacillary grade II flora) cases) were analyzed using 454 pyrosequencing of the hypervariable regions V3-V4 of the 16S rRNA gene and 16 quantitative bacterial species/genus-specific real-time PCR assays. Sensitivities and specificities of potential BV markers were computed using the Amsel criteria as reference standard for BV. The use of quantitative thresholds for prediction of BV, determined for both relative abundance measured with 454 pyrosequencing and bacterial load measured with qPCR, was evaluated. Results: Relative to the healthy women, the BV patients had in their vaginal microbiota significantly higher prevalence, loads and relative abundances of the majority of BV associated bacteria. However, only Gardnerella vaginalis, Atopobium vaginae, Eggerthella, Prevotella, BVAB2 and Megasphaera type 1 detected at or above optimal thresholds were highly predictable for BV, with the best diagnostic accuracy shown for A. vaginae. The depletion of Lactobacillus species combined with the presence of either G. vaginalis or A. vaginae at diagnostic levels was a highly accurate BV predictor. Conclusions: Quantitative determination of the presence of G. vaginalis, A. vaginae, Eggerthella, Prevotella, BVAB2 and Megasphaera type 1 as well as the depletion of Lactobacillus was highly accurate for BV diagnosis. Measurements of abundance of normal and BV microbiota relative to total bacteria in vaginal fluid may provide more accurate BV diagnosis, and be used for test-of-cure, rather than qualitative detection or absolute counts of BV related microorganisms

Analysis of Idioms in Articles on Brexit

Šajā Bakalaura darbā tiek veikta idiomu lietojuma analīze The Independent un The Telegraph rakstos par Brexit. Brexit tēma tika izvēlēta, ņemot vērā šī brīža politisko situāciju, Apvienotajai Karalistei stājoties ārā no Eiropas Savienības. Pētījuma korpuss sastāv no 20 The Independent un The Telegraph rakstiem, kurās tika atrastas 61 idioma. Pētījumā tika pielietotas kvalitatīvās un kvantitatīvās pētniecības metodes, lai noteiktu biežāk pielietotos idiomu tipus izvēlētajos rakstos. Tika secināts, ka visbiežāk pēc uzbūves izmantotas ir idiomas ar darbības vārdiem un pēc semantiskā aspekta, visbiežāk izmantotas ir pilnīgās idiomas. Visbiežākais idiomu pielietojuma mērķis ir izvairīties no gariem aprakstiem un paskaidrojumiem.This Bachelor thesis carries out the analysis of the use of idioms in The Independent and The Telegraph newspaper articles on Brexit. The topic of Brexit was chosen due to the current political situation of the UK leaving the EU. The corpus consists of 20 articles from The Independent and The Telegraph which contains 61 idioms discovered. Qualitative and quantitative research methods were applied in order to classify and determine the most frequently used idiom types, as well as the purpose of idioms in the selected articles. It has been concluded that structure-wise, the most frequently used idioms are verbal idioms and semantically, the most frequently used idioms are pure idioms. The most common purpose for the use of idioms is to avoid lengthy descriptions and explanations

Prevalence of vaginal bacterial species/genera by real-time PCR.

<p>The qualitative detection rates of 16 bacteria by species/genus-specific PCR assays in healthy control women (n = 79), intermediate cases (n = 11) and BV patients (n = 73) are presented. <i>L. iners</i> was the most frequently detected bacterium in the healthy control women (86%), followed by <i>G. vaginalis</i> (78%), <i>A. vaginae</i> (63%), <i>Prevotella</i> (62%), and <i>F. magna</i> (58%). In the intermediate subjects, the most common species/genera were <i>G. vaginalis</i> (100%), <i>L. iners</i> (91%), <i>A. vaginae</i> (91%), <i>Prevotella</i> (82%) and <i>L. amnionii</i> (82%). <i>G. vaginalis</i> and <i>A. vaginae</i> were both found in 100% of the subjects with BV. Other highly prevalent bacteria in the BV patients were <i>Prevotella</i> (96%), <i>Megasphaera</i> type 1 (96%), <i>L. iners</i> (93%), <i>Eggerthella</i> (93%), BVAB2 (90%), <i>L. amnionii</i> (88%) and <i>S. sanguinegens</i> (81%).</p

Relative abundances of bacterial species/genera by 454 pyrosequencing.

<p>The figure presents the average relative abundances of 16 bacterial species/genera by 454 pyrosequencing in the vaginal samples from healthy control women (n = 79), intermediate cases (n = 11) and BV patients (n = 73). The healthy control women had vaginal microbiota dominated by <i>Lactobacillus</i> species, accounting for nearly 90% of all sequences, with <i>L. crispatus</i> and <i>L. iners</i> highly prevailing over other lactobacilli. In the intermediate cases, <i>L. iners</i> and <i>G. vaginalis</i> were dominating over other species, accounting together for nearly 75% of all sequences. The BV patients possessed a diverse array of bacteria, with the most abundant species being <i>G. vaginalis</i>, <i>Prevotella</i>, <i>Megasphaera</i> type 1, <i>A. vaginae</i>, <i>L. amnionii</i>, <i>L. iners</i>, BVAB1, BVAB2, <i>S. sanguinegens</i> and <i>Eggerthella</i>.</p