Epidemiology of Streptococcus pyogenes upper respiratory tract infections in Poland (2003-2017).

Streptococcus pyogenes (group A Streptococcus, GAS) is a major human pathogen and causes every year over 600 millions upper respiratory tract onfections worldwide. Untreated or repeated infections may lead to post-infectional sequelae such as rheumatic heart disease, a major cause of GAS-mediated mortality. There is no comprehensive, longitudinal analysis of the M type distribution of upper respiratory tract strains isolated in Poland. Single reports describe rather their antibiotic resistance patterns or focus on the invasive isolates. Our goal was to analyse the clonal structure of the upper respiratory tract GAS isolated over multiple years in Poland. Our analysis revealed a clonal structure similar to the ones observed in high-income countries, with M1, M12, M89, M28, and M77 serotypes constituting over 80% of GAS strains. The M77 serotype is a major carrier of erythromycin resistance and is more often correlated with upper respiratory tract infections than other serotypes.

Twenty-Month Monitoring of Humoral Immune Response to BNT162b2 Vaccine: Antibody Kinetics, Breakthrough Infections, and Adverse Effects.

BACKGROUND: Vaccination is one of the most effective life-saving medical interventions, and the introduction of SARS-CoV-2 vaccines was intended to prevent the serious implications of COVID-19. The objectives of the study were (i) to observe the humoral immune response to the BNT162b2 vaccine and SARS-CoV-2 infection (mainly breakthrough infections), (ii) to demonstrate the persistence of anti-SARS-CoV-2 antibodies over time in relation to the number of received vaccine doses and the course of infection, and (iii) to determine the adverse effects after primary vaccine doses. METHODS: To assess the humoral response, IgG and IgA anti-S1 antibodies were quantified by ELISA assays. In total, the tests were carried out seven times in almost two years. RESULTS: We demonstrated strong immunogenicity (compared to levels before primary vaccination, 150- and 20-fold increases in IgG and IgA, respectively) of the BNT162b2 vaccine. Over time, we observed a systematic decline in antibody levels, which may have contributed to breakthrough infections. Although they caused seroconversion similar to the booster, antibody levels in such patients fell more rapidly than after re-vaccination. On the other hand, in individuals who did not receive booster(s) and who did not present breakthrough infection, anti-SARS-CoV-2 antibodies returned to pre-vaccination levels after 20 months. The most commonly recognized adverse effects were injection site redness and swelling. CONCLUSION: Vaccination is highly effective in preventing the most severe outcomes of COVID-19 and should be performed regardless of prior infection. Booster doses significantly enhance anti-SARS-CoV-2 antibody levels and, in contrast to those obtained by breakthrough infection, they remain longer.

Clinical Validation of GenBody COVID-19 Ag, Nasal and Nasopharyngeal Rapid Antigen Tests for Detection of SARS-CoV-2 in European Adult Population.

Accurate and rapid identification of COVID-19 is critical for effective patient treatment and disease outcomes, as well as the prevention of SARS-CoV-2 transmission. Rapid antigen tests (RATs) for identifying SARS-CoV-2 are simpler, faster and less expensive than molecular assays. Any new product to be considered a medical device is subject to evaluation and data analysis to verify the in vitro diagnostic ability to achieve its intended purpose. Clinical validation of such a test is a prerequisite before clinical application. This study was a clinical validation on adult Europeans of GenBody COVID-19 Ag, nasal and nasopharyngeal RATs. A set of 103 positive and 301 negative from nose and nasopharynx samples confirmed by RT-qPCR were examined. The tests were safe to use and showed 100% specificity in both specimens, and high sensitivity of 94.17% (95%CI 87.75% to 97.83%) and 97.09% (95%CI 91.72% to 99.4%), respectively. The parameters were significantly better for samples with higher virus loads (the highest for CT ≤ 25). The GenBody COVID-19 Ag RATs are inexpensive (compared to RT-qPCR), reliable and rapid with high sensitivity and specificity, making them suitable for diagnosis and timely isolation and treatment of COVID-19 patients, contributing to the better control of virus spread.

Differentiation of SARS-CoV-2 Variants Using RT-qPCRs by Targeting Recurrent Mutation Sites: A Diagnostic Laboratory Experience from Multi-Center Regional Study, August 2020-December 2021, Poland.

Rapid identification of SARS-CoV-2 variants is essential for epidemiological surveillance. RT-qPCR-based variant differentiation tests can be used to quickly screen large sets of samples for relevant variants of concern/interest; this study was conducted on specimens collected at 11 centers located in Poland during routine SARS-CoV-2 diagnostics between August 2020 and December 2021. A total of 1096 samples (with CT < 30) were screened for Alpha, Beta, Delta, Kappa and Omicron variants using commercial assays targeting repeat mutation sites. Variants were assigned to 434 (39.6%) specimens; the remaining 662 (60.4%) samples were not classified (no tested mutations detected). Alpha (n = 289; 66.59%), Delta (n = 115; 26.5%), Kappa (n = 30; 6.91%) and Omicron (n = 2; 0.46%) variants were identified and their distribution changed over time. The first Alpha variant appeared in October 2020, and it began to gradually increase its proportion of the virus population by June 2021. In July 2021, it was replaced by the Delta variant, which already dominated by the end of the year. The first Kappa was detected in October 2021, while Omicron was found in December 2021. The screening of samples allowed the determination of epidemiological trends over a time interval reflecting the national COVID-19 waves.

Viral Etiological Agent(s) of Respiratory Tract Infections in Symptomatic Individuals during the Second Wave of COVID-19 Pandemic: A Single Drive-Thru Mobile Collection Site Study.

One of the tools to contain the SARS-CoV-2 pandemic was to increase the number of performed tests and to improve the access to diagnostics. To this effect, mobile collection sites (MCSs) were established. This study was performed on samples collected at the MCS between November 2020 and March 2021. We aimed to confirm/exclude SARS-CoV-2, differentiate SARS-CoV-2 variants, and detect other respiratory pathogens. SARS-CoV-2 and other respiratory viruses were identified by RT-qPCRs. A total of 876 (46.35%) SARS-CoV-2 positive specimens in the diagnostic tests were identified. The wild-type variant was determined in 667 (76.14%) samples; the remaining 209 (23.86%) samples specimens were identified as Alpha variant. A total of 51 (5.6%) non-SARS-CoV-2 cases were detected in retrospective studies. These accounted for 33 cases of mono-infection including rhinovirus (RV), human adenovirus (HAdV), human metapneumovirus (HMPV), enterovirus (EV), and influenza virus, and 18 cases of co-infection (SARS-CoV-2 with RV or HAdV or HMPV, and RV with EV). Our research shows that the results obtained from the MCS have value in epidemiological studies, reflecting national trends on a micro scale. Although the spread of COVID-19 is a major public health concern, SARS-CoV-2 is not the only pathogen responsible for respiratory infections.

Novel Molecular Targets of Antidepressants.

Antidepressants target a variety of proteins in the central nervous system (CNS), the most important belonging to the family of G-protein coupled receptors and the family of neurotransmitter transporters. The increasing number of crystallographic structures of these proteins have significantly contributed to the knowledge of their mechanism of action, as well as to the design of new drugs. Several computational approaches such as molecular docking, molecular dynamics, and virtual screening are useful for elucidating the mechanism of drug action and are important for drug design. This review is a survey of molecular targets for antidepressants in the CNS and computer based strategies to discover novel compounds with antidepressant activity.

Impact of the Nucleic Acid Extraction Method and the RT-qPCR Assay on SARS-CoV-2 Detection in Low-Viral Samples.

COVID-19 was initially reported in China at the end of 2019 and soon thereafter, in March 2020, the WHO declared it a pandemic. Until October 2021, over 240 million COVID-19 cases were recorded, with 4.9 mln deaths. In order to stop the spread of this disease, it is crucial to monitor and detect any infected person. The etiologic agent of COVID-19 is a novel coronavirus called SARS-CoV-2. The gold standard for the detection of the virus is the RT-qPCR method. This study evaluated two RNA extraction methods and four commercial RT-qPCR assays routinely used in diagnostic laboratories for detecting SARS-CoV-2 in human specimens from the upper respiratory tract. We analyzed a panel of 70 clinical samples with varying RNA loads. Our study demonstrated the significant impact of the diagnostic methods selected by the laboratory on the SARS-CoV-2 detection in clinical specimens with low viral loads.

Case Report of COVID-19 after Full Vaccination: Viral Loads and Anti-SARS-CoV-2 Antibodies.

The introduction of effective vaccines against SARS-CoV-2 is expected to prevent COVID-19. However, sporadic cases of infection in vaccinated persons have been reported. We describe a case of a double-dose vaccinated woman with COVID-19. All stages of infection were observed, from no identification of virus, then the start of the infection, a high viral load, coming out of viraemia, and finally no detection of the virus. Despite the high viral load, the woman demonstrated mild COVID-19 symptoms, manifested only by a sore throat. The antibody results showed that she produced both post-infectious and post-vaccination immune responses. Phylogenetic analysis of the obtained viral genome sequence indicated that the virus belonged to the UK SARS-CoV-2 lineage B.1.1.7 (GR 501Y.V1; 20I/S:501Y.V1; Alpha variant).

Oncotoxic Properties of Serotonin Transporter Inhibitors and 5-HT1A Receptor Ligands.

The cytotoxic activity of several serotonin transporter (SERT) inhibitors and subtype of serotonin receptor 1A (5-HT1A receptor) ligands have been examined in androgen-insensitive human PC-3 prostate and neuroblastoma SH-SY5Y cancer cells. Almost all of the studied compounds (except 5-HT1A receptor agonist (2R)-(+)-8-Hydroxy-2-(di-n-propylamino)tetralin hydrobromide (8-OH-DPAT)) exhibited absolute cytotoxic activity against the examined cancer cells. The compound 4-Fluoro-N-[2-[4-(7-methoxy-1-naphthalenyl)-1-piperazinyl]ethyl]benzamide hydrochloride (S14506) that showed highest activity against neuroblastoma tumors was the 5-HT1A receptor agonist (although not alike other 5-HT1A receptor agonists). On the other hand, the compound 6-nitro-2-(4-undecylpiperazin-1-yl)quinoline hydrochloride (AZ07) that had the highest activity against PC-3 prostate cancer cells was a compound exhibiting antagonistic activity against the 5-HT1A receptor. Thus, compounds of oncotoxic properties S14506 and AZ07 should be evaluated further for their potential use in the prevention and treatment of cancer. Most of the 15 compounds tested exhibited either agonistic or antagonistic activity for both the cyclic adenosine monophosphate (cAMP) and extracellular signal-regulated kinase 1 and 2 (ERK1/2) pathways in human embryonic kidney 293 (HEK293) cells that overexpress the 5HT1AR gene. However, compounds paroxetine, N-Ac-paroxetine and 2-[4-(cyclobutylmethyl)piperazin-1-yl]-6-nitroquinoline hydrochloride (AB22) simultaneously exhibited antagonistic activity on the cAMP pathway and agonistic activity on the ERK1/2 pathway. Fluoxetine relative to compound AZ07 had almost three times lower cytotoxic activity against PC-3 prostate cancer cells. However, the proapoptotic activity of fluoxetine compared to compound AZ07 is almost two times higher which would suggest that the cytotoxic activity of both compounds may be dependent on different cell death mechanisms. Compound S14506 was found to be an antagonist of the serine-threonine protein kinase B (Akt) pathway. Prosurvival Akt activity may be reversed by Akt antagonists. Therefore, the antagonistic activity of S14506 on the Akt pathway may evoke caspase-3 expression and cytotoxicity. It appears that one should not expect a straightforward relationship between the activation of particular serotonergic pathways by selective serotonin reuptake inhibitors (SSRIs) and 5-HT1A receptor ligands and their cytotoxic or cytoprotective activity. Additionally, nuclear transcription factor κB (NF-κB), which may be involved in 5-HT-dependent biochemical pathways by coordinating different subunits in the formation of a dimer, may regulate the transcription of different transduction pathways. Therefore, it can be suggested that the mechanism of the cytotoxic activity of certain compounds (serotonergic against nonserotonergic) may depend on the compound and cancer type being examined. Docking studies showed that S14506, buspirone and spiperone bind in similar ways in the 5-HT1A receptor model and interacted with similar 5-HT1A receptor residues. S14506 and spiperone were found to be located closer to both phenylalanines in TM6 than buspirone, thus exhibiting more antagonist binding modes.

Shear bond strength of epoxy resin-based endodontic sealers to bovine dentin after ozone application.

The idea of using ozone to disinfect root canals is of recent origin. The wide acceptance of epoxy resin-based sealers lead us to investigate whether ozone can influence the adhesion to the dentin. In this study, we tested the shear bond strength of AH Plus and EZ Fill. Forty freshly extracted bovine teeth were randomly divided into 5 groups. 16 of these samples were treated with ozone for 60 seconds (HealOzone, Kavo). 8 samples were conditioned with the G Bond bonding system. The groups tested were: (1) AH Plus, (2) AH Plus and ozone, (3) EZ Fill, (4) EZ Fill and ozone, (5) AH Plus and G Bond. 48 hours after being prepared the specimens were tested for shear bond strength. Statistical analysis showed significant differences between materials (AH Plus > EZ Fill) and significant, positive influence of ozone and bonding agent on the shear bond strength.

Evolution of TEM-type extended-spectrum beta-lactamases in clinical Enterobacteriaceae strains in Poland.

Seventeen extended-spectrum beta-lactamase (ESBL)-producing isolates of the family Enterobacteriaceae recovered from 1998 to 2000 in hospitals of five different cities in Poland were analyzed. They expressed several TEM-type ESBLs, TEM-4, TEM-29, TEM-85, TEM-86, TEM-93, and TEM-94. TEM-85 (L21F, R164S, E240K, T265M), TEM-86 (L21F, R164S, A237T, E240K, T265M), TEM-93 (M182T, G238S, E240K), and TEM-94 (L21F, E104K, M182T, G238S, T265M) were identified for the first time. Including the enzymes described earlier, TEM-47, TEM-48, TEM-49, and TEM-68, the group of known ESBLs of the TEM family produced by enterobacteria in Polish hospitals has increased to 10 variants. Comparative sequence analysis of the genes coding for all these beta-lactamases revealed a view of their possible evolution, which, apart from the gradual acquisition of various mutations, could also have involved recombination events. Two different bla(TEM-1) gene alleles were precursors of the ESBL genes: bla(TEM-1A), which was the ancestor of bla(TEM-93), and bla(TEM-1F), from which all the remaining genes originated. The evolution of the bla(TEM-1F)-related genes most probably consisted of three major separate lineages, one of which, including bla(TEM-4), bla(TEM-47), bla(TEM-48), bla(TEM-49), bla(TEM-68), and bla(TEM-94), was highly structured itself and could have been initiated by the bla(TEM-25) gene, identified exclusively in France so far. Plasmid fingerprinting analysis revealed a high degree of diversity of plasmids carrying related bla(TEM) genes, which suggested either the intense diversification or transposition of bla(TEM) genes between different plasmids or some contribution of convergent evolution. The results of this study clearly demonstrate that the environment of Polish hospitals has been highly favorable for the rapid evolution of ESBLs.

[Prevalence of antibodies against Anaplasma phagocytophilum, Babesia microti i Borrelia burgdorferi in adults in North-Eastern Poland]. / Wystepowanie przeciwcial przeciw Anaplasma phagocytophilum, Babesia microti i Borrelia burgdorferi u doroslych z pólnocno-wschodnich rejonów Polski.

THE AIM: of the study was to evaluate the seroprevalance of antibodies against Anaplasma phagocytophilum and Babesia Microti in healthy north-eastern Poland, adult population. MATERIAL AND METHODS: The study was conducted in a group of 142 healthy adults (mean age 19-22), bitten by ticks within last 2 years. The control group consisted of 50 adults from central Poland (nonendemic area). The antibody levels for A. phagocytophilum (IgG/Ap-Ab) and B. microti (IgM/Bm-Ab) were evaluated in two series of samples from the same persons (interval 5-6 months) by immunoenzymatic tests (Borrelia Biomedica, Austria), immunofluorescence test (Human Granulotic Ehrlichiosis IFA IgG and Babesia microti IFA IgG from MRL Diagnostics). RESULTS: Positive results for A. phagocytophilum were defined as titres > or =1:256 and for B. microti > or =1:64 and B. burgdorferi > or = 11 BBU/ml. Positive results for IgG B. burgdorferi during the first collection were revealed in 16% (n=24/142) of individuals from endemic area and in 4% (n=2/50) of the control group, which was statistically relevant (p<0,05). IgG A. phagocytophilum antibodies were present in 3,5% (n=5/142) of individuals from the endemic area, but for IgG B. microti antibodies (IgG/Bm-Ab) no positive results were found. No IgG antibodies against A. phagocytophilum and B.microti, were found in individuals from non-endemic area. During the second collection, in individuals from the endemic area, the antibodies against B. burgdorferi were found in 9,8% (n=14/142), IgG A. phagocytophilum antibodies (IgG/Ap-Ab) in 4,9% (n=7/142) and against B. microti (IgG/ Bm-Ab) in 1,4% (n=2/142). The antibodies against B. Burgdorferi were found in 2% (n=1/150) of the control group during the second collection, and no IgG against A. phagocytophilum and B. microti were found. CONCLUSION: [corrected] Evaluating the seroprevalance of the studied antibodies in both collections, a conclusion was drawn that there was no significant increase of antibodies levels directly after the highest exposition to tick bites. None of individuals showed 4-fold antibody level increase between the first and second collection. The seroconversion for IgG/Bm-Ab antibodies was present in 1,4% (n=2/142) of individuals, in those 2 cases a 2-fold antibodies level increase was observed. As far as IgG/Ap-Ab antibodies are concerned the seroconversion was observed in 2,1% (n-3/142), but only one case shown a 3-fold antibodies level increase. No seroconversion of B. burgdorferi antibodies were found in the second collection.

[Chlamydia pneumoniae infection in patients with advanced carotid atherosclerosis]. / Zakazenia Chlamydia pneumoniae u chorych z zaawansowana miadyca tetnic szyjnych.

Despite the growing number of scientific reports showing different markers of infection caused by Chlamydia pneumoniae in patients with advanced atherosclerosis, there is still no clear confirmation of a pathogenetic link between this infection and atherogenesis. The aim of the present study was to investigate the presence C. pneumoniae DNA in peripheral blood mononuclear cells and carotid endarterectomy samples obtained from patients with advanced atherosclerosis according to the presence specific antibodies against C. pneumoniae in serum. The levels of IgG, IgM and IgA antibodies to C. pneumoniae were determined by enzyme immunoassay (EIA) in sera of 36 patients with advanced atherosclerosis undergoing carotid endarterectomy. The presence of C. pneumoniae DNA in the carotid samples and in peripheral blood mononuclear cells was investigated by a nested polymerase chain reaction (PCR). We have not confirm the presence of C. pneumoniae DNA either in the carotid endarterectomy samples or in peripheral blood mononuclear cells, both in patients having the specific antibodies against C. pneumoniae and in seronegative patients. In the studied group of patients with advanced carotid atherosclerosis there was no correlation between the presence of specific antibodies against C. pneumoniae and the presence of C. pneumoniae DNA in endarterectomy samples and peripheral blood mononuclear cells.

Lack of significant differences in immunity against diphtheria between populations of Eastern and Western regions of Poland.

Incidents of diphtheria in countries which were formerly part of the Soviet Union (Ukraine, Russia and Belorus) resulted in the need to evaluate thoroughly the effectiveness of preventive vaccination in Poland, especially in the border regions of the country where the biggest migration of population can be observed. The aim of this work was a comparison of the immunity to diphtheria in two geographically different regions of Poland--eastern (Lublin) and western (Zielona Gora) ones. It showed immunoprophylaxis to diphtheria that was implemented on these areas. Diphtheria antitoxin level (IgG) was determined with application of the ELISA method in 1236 (529/707) people. No significant differences were found in the level of antibodies in the groups < 2 years of age and > 19 years of age in people below the protective titre (0.1 IU/ml). The difference occurring in the interval between 2nd and 18th year of life (in western Poland 7.6% and in eastern Poland 16%) may result from different implementation of the vaccination program in these regions (booster doses). Recommendations for vaccination to diphtheria in people over 25 years of age should be implemented especially in the frontier regions of Poland adjoining countries threatened with diphtheria occurrence.