Polarizacija citokina Th1 / Th2 u mlijeku u odnosu na patogene uzročnike subkliničkog mastitisa kod krava

The aim of this study to determine the Th1/Th2 cytokine balance in milk according to the bacterial species that cause subclinical mastitis in cows. The California Mastitis Test (CMT) was applied to the selected cows. The cows were divided into four groups: cows with negative CMT (n = 45); Escherichia coli (E. coli) group included only cows with E. coli growing in CMT-positive milk samples (n = 45); Streptococcus agalactiae (S. agalactiae) group included cows with only S. agalactiae growing in CMT-positive milk samples (n = 45); Staphylococcus aureus (S. aureus) group included cows with only S. aureus growing in CMT-positive milk samples (n = 45). Somatic cell count (SCC) in fresh milk samples was measured using the DeLaval Cell Counter device. Also, cytokine analyses were performed using Species-specific commercial ELISA kits. Tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) concentrations were relatively high in the E. coli group, but the interleukin (IL)-2 concentration was low. The lowest concentration of IL-4 was found in the CMT-negative group. The highest IL-5 concentration was found in the S. agalactiae group, while the highest milk IL-10 concentration was found in the S. aureus group. Also, T helper (Th1/Th2) polarization shifted towards Th1 in milk with mastitis caused by E. coli. Th1/Th2 polarization was shifted to Th2 in milk with mastitis caused by S. aureus and S. agalactiae. Based on our findings, cellular immunity should be maintained in mastitis cases due to E. coli, and humoral immunity should be supported in mastitis caused by S. aureus and S. agalactiae.Cilj ovog rada bio je odrediti ravnotežu između citokina Th1 i Th2 u odnosu na bakterijske uzročnike subkliničkog mastititsa kod krava. Pri tom su krave bile podjeljene u slijedeće testne skupine: krave s negativnim testom na mastitits CMT- (n = 45); grupa oznake Escherichia coli (E. coli) uključivala je jedinke kojima je određen samo porast soja E. coli u uzorcima s pozitivnim CMT testom (n = 45); Streptococcus agalactiae (S. agalactiae) grupa uključivala je jedinke kojima je određen samo porast soja S. agalactiae u uzorcima s pozitivnim CMT testom (n = 45); Staphylococcus aureus (S. aureus) grupa uključivala je jedinke kojima je određen samo porast soja S. aureus u uzorcima s pozitivnim CMT testom (n = 45). Broj somatskih stanica (SCC) u uzorcima svježeg mlijeka određivan je pomoću brojača DeLaval Cell Counter. Analize koncentracije citokina provedene su ELISA metodom koristeći gotove selektivne kitove za pojedinu bakterijsku vrstu koja je određivana. Koncentracije alfa tumorskog faktora nekroze (TNF-α) i gama-interferona (IFN-γ) bile su relativno visoke u grupi E. coli, no koncentracija interleukina (IL)-2 je bila niska. Najniža koncentracija IL-4 određena je u grupi CMT-odnosno u jedinki koje nisu imale mastitis. Najviša koncentracija IL-5 određena je u grupi S. agalactiae, dok je najviša koncentracija IL-10 određena u grupi S. aureus. Također, ravnoteža pomoćničkih T-limfocita (Th1/Th2) polarizirala se u smjeru koncentracije Th1 u uzorcima mastitičnog mlijeka grupe E. coli. S druge strane u grupama S. aureus i S. agalactiae ravnoteža Th1/Th2 se polarizirala u smjeru Th2. Uzimajući u obzir rezultate ovog istraživanja, nalaže se zaključak da je kod mastitisa uzrokovanog bakterijom E. coli potrebno održavati stanični imunitet, dok je kod mastitisa uzrokovanog bakterijama S. aureus i S. agalactiae potrebno održavati humoralni imunitet

Differential antibody response to COVID-19 disease and COVID-19 vaccines

Background: In our study, antibody positivity was evaluated by two methods in vaccinated and unvaccinated people according to their demographic characteristics and history of COVID-19. Methods: In this study, venous blood samples were taken from patients who were requested to have COVID-19 antibodies from our hospital's outpatient clinics between February 2022 and March 2022. Results: There was no statistically significant difference when IgG antibody positivity was compared according to the age ranges in chemiluminescence and immunochromatographic methods. When patients were evaluated according to antibody titers, it was found that 81% of the seronegative patients were unvaccinated and had not had Covid-19, and it was found that this group was statistically significant compared to other groups. Conclusions: It has been concluded that it will be of great importance for every country, even every region, to have a test and vaccine policy for diagnosis and follow-up in the fight against COVID-19

Interpretation of SARS-CoV-2 behaviour on different substrates and denaturation of virions using ethanol: an atomic force microscopy study

Coronavirus (SARS-CoV-2) is a respiratory infection virus that was first detected in Wuhan, China. The virus causes COVID-19 disease and the outbreak was recognised as a pandemic by the World Health Organization (WHO) in March 2020. SARS-CoV-2 virion was first imaged using cryo-electron microscopy by the Chinese Center for Disease Control and Prevention (CDC). Atomic Force Microscopy is a unique technique that can allow imaging of biomolecules under different conditions. In this work, we used Atomic Force Microscopy to characterize SARS-CoV-2 on tissue culture polystyrene (TCPS) and glass coverslip surfaces. We isolated SARS-CoV-2 and drop casted it on coverslip glass and tissue culture polystyrene surfaces. We analyzed height profiles, density, and aggregation behavior of the virion on glass and polystyrene surfaces. We observed the coffee ring effect on the drop casted samples and close packing of virions near the coffee rings on both surfaces with relatively higher virion distribution on the tissue culture polystyrene (TCPS) substrates. We compare virion agglomeration on the two types of surfaces. Finally, we applied ethanol disinfectant to virions on the surface to visualize the effect of ethanol and image the ultrastructure of SARS-CoV-2

Investigation of Carbapenemases in Carbapenem-Resistant Escherichia coli and Klebsiella pneumoniae Strains Isolated in 2014 in Turkey

Carbapenems are the choice of treatment in infections caused by multidrug resistant Enterobacteriaceae. In recent years carbapenem-resistant Enterobacteriaceae isolates due to carbapenemases have been increasingly reported worldwide. Multicenter studies on carbapenemases are scarce in Turkey. The aim of this study was to determine the distribution of carbapenemases from different parts of Turkey as a part of the European Survey of Carbapenemase Producing Enterobacteriaceae (EuSCAPE) project. Beginning in November 2013, carbapenem-resistant isolates resistant to at least one of the agents, namely imipenem, meropenem, and ertapenem were sent to the coordinating center. Minimum inhibitory concentrations for these carbapenems were determined by microdilution tests following EUCAST guidelines. Production of carbapenemase was confirmed by combination disk synergy tests. Types of carbapenemases were investigated using specific primers for VIM, IMP; NDM, KPC and OXA-48 genes by multiplex polymerase chain reaction. In a six month period, 155 suspected carbapenemase-positive isolates were sent to the coordinating center of which 21 (13.5%) were E.coli and 134 (86.5%) were K.pneumoniae. Nineteen (90.5%) strains among E.coli and 124 (92.5%) strains among K.pneumoniae were shown to harbour at least one carbapenemase gene by molecular tests, with a total of 92.3% (143/155). Carbapenemases were determined as a single enzyme in 136 strains (OXA-48: 84.6%; NDM: 6.3%; VIM: 2.8%; IMP: 1.4%) and as a combination in seven isolates (OXA-48 + NDM: 2.1%; OXA-48 + VIM: 2.1%; VIM + NDM: 0.7%). KPC was not detected in any of the isolates. According to the microdilution test results, resistance to imipenem, meropenem and ertapenem in OXA-48 isolates were 59.5%, 52.9% and 100%, respectively. The combination disk synergy test was 100% compatible with the molecular test results. As most of the OXA-48 producing isolates were susceptible to meropenem but all were resistant to ertapenem, ertapenem seems to be the most sensitive agent in screening carbapenemases in areas where OXA-48 is prevalent and phenotypic combination tests can be useful in centers where molecular tests are not available.Wo

Evaluation of the results of MOTAKK hepatitis C virus RNA genotyping and hepatitis delta virus external quality assessment programs during 2015-2016

Background/Aims: To evaluate the HCV RNA genotyping and HDV RNA tests that are performed in molecular microbiology laboratories in Turkey as part of a national external quality assessment programme, MOTAKK (Molekuler Tanida Kalite Kontrol) (English translation: Quality control in molecular diagnostics)

Evaluation of the results of MOTAKK hepatitis C virus RNA genotyping and hepatitis delta virus external quality assessment programs during 2015-2016

Background/Aims: To evaluate the HCV RNA genotyping and HDV RNA tests that are performed in molecular microbiology laboratories in Turkey as part of a national external quality assessment programme, MOTAKK (Molekuler Tanida Kalite Kontrol) (English translation: Quality control in molecular diagnostics). Materials and Methods: Plasmas having different HCV RNA genotypes were used to prepare HCV genotype control sera. The HDV RNA main stock was prepared from patients with chronic delta hepatitis who had a significant amount of viral load detected, as per the WHO reference materials on viral load studies that were compiled for the purpose of developing HDV RNA control sera. Samples with different viral loads were prepared from this main stock by dilution. The prepared controls were delivered to the registered laboratories. The laboratories carried out the relevant tests and entered their results via the MOTAKK web page. External quality assessment (EQA) reports of the participants were uploaded to the website as well. Results: In total, there were 23 participating laboratories, out of which 20 exclusively performed HCV genotyping, and 15 and 16 only performed HDV RNA in 2015 and 2016, respectively. The success rate of the results of the HCV genotype was 56-96\% in 2015 and 30-95\% in 2016. The tube with a 30\% success rate had a recombinant type of HCV, therefore, it could not be detected in most of the laboratories. The HDV RNA results were evaluated qualitatively. Accordingly, HDV RNA detection rates of participant laboratories were 71-100\% in 2015 and 50-100\% in 2016. Conclusion: This study was the first national external quality control program in Turkey regarding HCV RNA genotyping and HDV RNA in the field of molecular microbiology, and it was implemented successfully