Is Mean Platelet Volume a Predictive Marker for the Development of Thrombosis in Patients with COVID-19 Infection?

Mean platelet volume (MPV) can provide important information about the course and prognosis of many diseases. MPV is an early indicator of platelet activation, which has an important role in the pathogenesis of thrombosis. In this study, we aimed to investigate whether MPV was a predictive marker for the development of thrombosis in hospitalized patients with COVID-19 infection. Fifty-seven patients whose courses were followed after the diagnosis of COVID-19 infection using a polymerase chain reaction test during the pandemic were included in the study. Our results demonstrated that there was a negative correlation between platelet count and MPV (r=0.470, p≤ 0.01), and there was a positive correlation between Platelet Distribution Width (PDW) and MPV (r=0,933, p≤ 0.01), but no significant correlation was found between the other variables and MPV.

Oncolytic Myxoma virus Increases Autophagy in Multiple Myeloma

Objective: Multiple myeloma, which affects plasma cells, is the second most common hematological malignancy. Despite the development of new drugs and treatment protocols, patient survival has not reached the desired level. In this study, we investigated the effects of Myxoma virus (MYXV), an oncolytic virus, on autophagy in myeloma cells. Materials and Methods: We analyzed protein expressions of ATG-5, p62, Beclin-1, LC3B, and the apoptosis marker Bcl-2 as autophagy markers in human U-266 and mouse MOPC-315 myeloma cell lines subjected to different doses of MYXV. In addition, autophagic images of myeloma cells were investigated using transmission electron microscopy (TEM). Results: In the first 24 h, which is the early stage of autophagy, ATG-5 and Beclin-1 expression levels were increased in the U-266 and MOPC-315 cell lines in the groups that had received MYXV at a multiplicity of infection of 15. At 48 h, a significant increase was detected in the expression of LC3B, which is a late indicator. Autophagosomes were observed in myeloma cells by TEM. Conclusion: MYXV shows an antimyeloma effect by increasing autophagy in myeloma cells.

[Investigation of the Effect of Farnesol on Biofilm Formation by Candida albicans and Candida parapsilosis Complex Isolates]. / Candida albicans ve Candida parapsilosis Kompleks Izolatlarinin Biyofilm Üretimi Üzerine Farnesol Etkisinin Arastirilmasi.

The incidence of infections caused by Candida species has significantly increased over the past three decades. Candida albicans is commonly recognized as the primary causative agent in cases of candidiasis; however, non-albicans Candida species, including Candida parapsilosis, are also frequently defined as pathogens. Treatment-resistant infections arise as a result of biofilm formation, which is one of the effective mechanisms in the pathogenesis of Candida infections. However, the mechanisms of action of farnesol, a quorum sensing (QS) system molecule, on biofilm formation by Candida species remain unclear. This study aimed to demonstrate the changes in the biofilm biomass of C.albicans and C.parapsilosis complex isolates in the presence of farnesol and reveal the expression of the EFG1 and BCR1 genes, which are believed to play a role in the production of QS molecules, using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analysis. C.albicans (n= 91) and C.parapsilosis complex (n= 29) isolates obtained from different clinical samples were included in the study. The minimum inhibitory concentration (MIC) values of farnesol were determined using the broth microdilution method according to the M27-A3 protocol of the Clinical and Laboratory Standards Institute (CLSI). The biofilm biomass of the isolates was examined without farnesol and at the MIC-0 and MIC-2 concentrations of farnesol. Changes in the expression of the biofilm-associated EFG1 and BCR1 genes were investigated using qRT-PCR. According to the results of the study, the MIC values of farnesol were detected in the range of 1-2 mM in 82.4% (n= 75) of the C.albicans isolates and in the range of 0.5-1 mM in 72.4% (n= 21) of the C.parapsilosis complex isolates. Of the C.albicans isolates, 27 (29.7%) exhibited a strong biofilm formation and 58 (63.7%) demonstrated a weaker biofilm formation, while these rates were 34.4% (n= 10) and 62.1% (n= 18), respectively, for the C.parapsilosis complex isolates. At the MIC-0 and MIC-2 concentrations, farnesol was observed to reduce biofilm biomass among C.albicans (n= 24, 88.9%) and C.parapsilosis complex (n= 8, 80.0%) isolates that formed strong biofilms and observed to increase biofilm biomass among those that formed weak biofilms [60.3% (n= 35) and 55.6% (n= 10), respectively]. On completion of the qRT-PCR analysis supporting the results of the biofilm experiment, it was determined that the expressions of the EFG1 and BCR1 genes decreased at the MIC-0 and MIC-2 concentrations of farnesol among the strong biofilm-forming C.albicans and C.parapsilosis complex isolates, but there was an increase in gene expressions among the weak biofilm-forming isolates. In addition to the antifungal effect of farnesol on Candida species, this study provided data on the efficacy of the MIC-0 and MIC-2 concentrations of farnesol against Candida biofilm biomass. Although our results suggest that farnesol can be used as an alternative agent to reduce biofilm formation in Candida infections, they need to be supported by further studies. Moreover, this research has significance as it represents the first study to determine the EFG1 and BCR1 gene expressions among C.parapsilosis complex isolates in the presence of farnesol.

Myxoma Virus Combination Therapy Enhances Lenalidomide and Bortezomib Treatments for Multiple Myeloma.

This study aimed to explore the effectiveness and safety of Myxoma virus (MYXV) in MM cell lines and primary myeloma cells obtained from patients with multiple myeloma. Myeloma cells were isolated from MM patients and cultured. MYXV, lenalidomide, and bortezomib were used in MM cells. The cytotoxicity assay was investigated using WST-1. Apoptosis was assessed through flow cytometry with Annexin V/PI staining and caspase-9 concentrations using ELISA. To explore MYXV entry into MM cells, monoclonal antibodies were used. Moreover, to explore the mechanisms of MYXV entry into MM cells, we examined the level of GFP-labeled MYXV within the cells after blocking with monoclonal antibodies targeting BCMA, CD20, CD28, CD33, CD38, CD56, CD86, CD117, CD138, CD200, and CD307 in MM cells. The study demonstrated the effects of treating Myxoma virus with lenalidomide and bortezomib. The treatment resulted in reduced cell viability and increased caspase-9 expression. Only low-dose CD86 blockade showed a significant difference in MYXV entry into MM cells. The virus caused an increase in the rate of apoptosis in the cells, regardless of whether it was administered alone or in combination with drugs. The groups with the presence of the virus showed higher rates of early apoptosis. The Virus, Virus + Bortezomib, and Virus + Lenalidomide groups had significantly higher rates of early apoptosis (p < 0.001). However, the measurements of late apoptosis and necrosis showed variability. The addition of MYXV resulted in a statistically significant increase in early apoptosis in both newly diagnosed and refractory MM patients. Our results highlight that patient-based therapy should also be considered for the effective management of MM.

Novel zinc oxide nanoparticles of Teucrium polium suppress the malignant progression of gastric cancer cells through modulating apoptotic signaling pathways and epithelial to mesenchymal transition.

Management of gastric cancer is still challenging due to resistance to current chemotherapeutics and recurrent disease. Moreover, green- synthesized zinc oxide nanoparticles (ZnO-NPs) using natural resources are one of the most promising therapeutic agents for anticancer therapy. Here we report the facile green synthesis and characterization of ZnO-NPs from Teucrium polium (TP-ZnO-NP) herb extract and the anticancer activities of these nanoparticles on gastric cancer cells. Facile green synthesis of TP-ZnO-NP was achieved using zinc acetate dihydrate. For the characterization of TP-ZnO-NP, UV-vis spectroscopy, FTIR, SEM, XRD and EDX analyses were performed. Antiproliferative and anticancer activities of TP-ZnO-NP were explored using the HGC-27 gastric cancer cell line model. MTT cell viability and colony formation assays were used for the analysis of cell proliferation and migration. Wound healing assay was used to analyze the migration capacities of cells. Annexin V/PI double staining, DNA ladder assay, and Acridine orange/Ethidium bromide staining were performed to analyze the induction of apoptosis. qPCR was used to determine gene expression levels of apoptotic and epithelial to mesenchymal transition marker genes. The aqueous extract of TP served as both a reducing and capping agent for the successful biosynthesis of zinc oxide nanoparticles. Remarkably, synthesized TP-ZnO-NPs were found to have significant antiproliferative and anticancer activities on HGC-27 gastric cancer cells. Collectively, current data suggest that TP-ZnO-NP is a novel and promising anticancer agent for future therapeutic interventions in gastric cancer.

Protective effects of Acetobacter ghanensis against gliadin toxicity in intestinal epithelial cells with immunoregulatory and gluten-digestive properties.

PURPOSE: The aim of this study was to establish whether Acetobacter ghanensis, the probiotic characteristics of which were evaluated previously, attenuates gliadin-induced toxicity in intestinal epithelial cells with gluten-digestive and immunoregulatory properties. METHODS: A co-culture model of human intestinal epithelial cell (Caco-2) monolayers on top of peripheral blood mononuclear cells (PBMCs) obtained from patients with celiac disease (CD) was established. The gluten-digestive properties of A. ghanensis were determined by checking bacterial growth in a medium containing gluten as the main nitrogen source. The mRNA levels of genes encoding TJ-associated proteins were measured by quantitative real-time PCR (qRT-PCR). The concentrations of IL-6 and TNFα were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: We found that PT-gliadin disrupted intestinal barrier integrity by modulating the expression of TJ-associated genes encoding zonulin (increased by ~ 60%), zonula occludens-1 (ZO-1) (decreased by ~ 22%), and occludin (decreased by ~ 28%) in Caco-2 cells. Furthermore, PT-gliadin treatment in Caco-2 cells was associated with increased concentrations of IL-6 (~ 1.6-fold) and TNFα (~ twofold) from PBMCs. These modulatory effects of PT-gliadin, however, were suppressed when Caco-2 cells were subjected to A. ghanensis in the presence of PT-gliadin. As a factor underlying these protective effects, we showed that A. ghanensis could digest gluten peptides. CONCLUSIONS: To our knowledge, the current study is the first to demonstrate that A. ghanensis improves intestinal barrier functions by attenuating the modulatory effects of PT-gliadin with immunoregulatory and gluten-digestive properties.

C-Reactive Protein-to-Albumin Ratio as a Prognostic Inflammatory Marker in COVID-19.

Objectives As a result of developed generalized inflammation, the main prognostic factor determining morbidity and mortality in coronavirus disease 2019 (COVID-19) patients is acute respiratory distress syndrome. The purpose of our study was to define (1) the laboratory tests that will contribute to the diagnosis and follow-up of COVID-19 patients, (2) the differences between the laboratory-confirmed (LC), unconfirmed (LUC), and control (C) groups, and (3) the variation between groups of acute-phase reactants and biomarkers that can be used as an indicator of disease severity and inflammation. Materials and Methods A total of 102 patients undergoing treatment with COVID-19 interim guidelines were evaluated. Reverse transcriptase-polymerase chain reaction (RT-PCR) test was positive in 56 (LC), classified as mild or severe, and negative in 46 (LUC) patients. In addition, 30 healthy subjects (C) with negative RT-PCR tests were also evaluated. All statistical analyses were performed with the SPSS 22.0 program and the p -values for significant findings were less than 0.05. Parametric/nonparametric distribution was determined by performing the Kolmogorov-Smirnov test for all groups. Student's t -test was used for variables with parametric distribution and the Mann-Whitney U-test for variables with the nonparametric distribution. A cut-off level for biomarkers was determined using the ROC (receiver operator characteristic) curve. Results In the LC group, platelet, platecrit, mean platelet volume, platelet diameter width, white blood cell, lymphocyte, eosinophil, neutrophil, immature granulocyte, immature lymphocyte, immature monocyte, large immune cell, and atypical lymphocyte counts among the complete blood count parameters of mature and immature cell counts showed a significant difference according to the C and LUC groups. C-reactive protein, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and C-reactive protein-to-albumin ratio (CAR) indices were significantly elevated in LC patients and were significantly higher in patients classified as severe compared to mild. When CAR optimal cutoff was determined as 0.475, area under the curve was 0.934, sensitivity was 90.91%, specificity was 86.21%, positive predictive value was 92.59%, and negative predictive value was 83.33%. The diagnostic accuracy for CAR was 89.29%. Conclusion The CAR index with the highest diagnostic value and the highest predictability could be the most useful biomarker in the diagnosis and evaluation of disease severity in COVID-19 patients.

Effects of Non-Thermal Treatment on Gilaburu Vinegar (Viburnum opulus L.): Polyphenols, Amino Acid, Antimicrobial, and Anticancer Properties.

Gilaburu (Viburnum opulus L.) is an important fruit that has been studied in recent years due to its phytochemicals and health benefits. In this study, traditionally produced vinegar made from gilaburu fruit (C-GV) was evaluated. Vinegar with higher levels of bioactive components optimized by response surface methodology (RSM) was also produced using ultrasound (UT-GV). The maximum optimization result for the bioactive components was achieved at 14 min and 61.2 amplitude. The effectiveness of thermal pasteurization (P-GV) on gilaburu vinegar was evaluated. An increase was detected for every organic acid with ultrasound treatment. In the UT-GV and C-GV samples, arabinose was present, which is useful for stimulating the immune system. Gilaburu vinegar samples contained 29-31 volatile compounds. The smallest amount of volatile compounds was found in P-GV (1280.9 µg/kg), and the largest amounts of volatile compounds were found in C-GV (1566.9 µg/kg) and UT-GV (1244.10 µg/kg). In the UT-GV sample, Fe was increased, but Ca, K, Mg, and Mn were decreased. A total of 15 polyphenols were detected in C-GV, P-GV, and UT-GV samples, and gallic acid was the most common. A total of 17 free amino acids were detected in gilaburu vinegar samples. Ultrasound provided enrichment in total phenolic compounds and total free amino acids. All three vinegar samples had good antimicrobial activity against pathogens. The efficacy of C-GV, P-GV, and UT-GV samples against colon and stomach cancer was determined, but there were no significant differences between them. As a result, ultrasound treatment is notable due to its antimicrobial and anticancer activity, especially for the enrichment of phenolic compounds and amino acids in gilaburu vinegar.

Immunogenicity and safety of the CoronaVac vaccine in patients undergoing treatment for breast and lung cancer.

OBJECTIVE: To compare seroconversion for SARS-CoV-2 receptor-binding domain (RBD) specific IgG positivity against two doses of the CoronaVac vaccine in breast and lung cancer patients receiving systemic therapy, to determine the factors affecting seropositivity, and to observe long-term results up to a secondary booster vaccine. RESULTS: The analysis included 201 cancer patients (99 breasts, 102 lungs; median age: 59 years (range: 28-92), 42.3 % men) and 97 controls (median age: 62 years (range: 24-87), 38.1 % men). The seropositivity rate for RBD IgG after 2 doses of vaccine in the cancer group was 81.6 % (n=164) and 93.8 % (n=91) in the control group (p=0.005). The median IgG titer of cancer patients was significantly lower than in the control group (338 (IQR, 95-933) AU/mL vs 676 (IQR, 389-1270) AU/mL; p<0.001). Multivariate analysis of all the patients determined that having cancer (OR: 0.303, 95%CI: 0.123-0.750, p=0.010) and being over 60 years of age (OR: 0.447, 95%CI: 0.218-0.917, p=0.028) was associated with a reduced vaccine response. A subgroup analysis of cancer patients revealed that seroconversion was lower in men than in women (75.3 % vs 86.2 %, p=0.049) and lower in ≥60 patients than in <60 patients (75.9 % vs 89.4 %, p=0.014). DISCUSSION AND CONCLUSION: Cancer patients receiving an active systemic therapy with two doses of the CoronaVac vaccine had a lower antibody response than the non-cancer population, and deaths due to COVID-19 may occur in these patients despite the vaccine. Therefore, extensive protective measures should be taken to protect against COVID-19 in cancer patients aged 60 years and older, who have received two doses of the CoronaVac vaccine (Tab. 4, Fig. 4, Ref. 27).

A 5-year surveillance of healthcare-associated infections in a university hospital: A retrospective analysis.

Objectives: "Nosocomial infections" or "healthcare-associated infections" are a significant public health problem around the world. This study aimed to assess the rate of laboratory-confirmed healthcare-associated infections, frequency of nosocomial pathogens, and the antimicrobial resistance patterns of bacterial isolates in a University Hospital. Methods: A retrospective evaluation of healthcare-associated infections in a University Hospital, between the years 2015 and 2019 in Tekirdag, Turkey. Results: During the 5 years, the incidence densities of healthcare-associated infections in intensive care units and clinics were 10.31 and 1.70/1000 patient-days, respectively. The rates of ventilator-associated pneumonia, central line-associated bloodstream infections, and catheter-associated urinary tract infections in intensive care units were 11.57, 4.02, and 1.99 per 1000 device-days, respectively. The most common healthcare-associated infections according to the primary sites were bloodstream infections (55.3%) and pneumonia (20.4%). 67.5% of the isolated microorganisms as nosocomial agents were Gram-negative bacteria, 24.9% of Gram-positive bacteria, and 7.6% of Candida. The most frequently isolated causative agents were Escherichia coli (16.7%) and Pseudomonas aeruginosa (15.7%). The rate of extended-spectrum beta-lactamase production among E. coli isolates was 51.1%. Carbapenem resistance was 29.8% among isolates of P. aeruginosa, 95.1% among isolates of Acinetobacter baumannii, and 18.2% among isolates of Klebsiella pneumoniae. Colistin resistance was 2.4% among isolates of A. baumannii. Vancomycin resistance was 5.3% among isolates of Enterococci. Conclusion: Our study results demonstrate that healthcare-associated infections are predominantly originated by intensive care units. The microorganisms isolated from intensive care units are highly resistant to many antimicrobial agents. The rising incidence of multidrug-resistant microorganisms indicates that more interventions are urgently needed to reduce healthcare-associated infections in our intensive care units.

Investigation of the Prevalence of Demodex spp. in Dermatological Diseases

Objective: An increase in the counts of the Demodex mites that exist in the microbiota of healthy individuals may lead to some dermatological diseases. This study aimed to investigate the prevalence of Demodex spp. among patients diagnosed with acne vulgaris, rosacea, perioral dermatitis, seborrheic dermatitis, eczema, and pityriasis folliculorum and the relationship between the demographic and clinical data of such patients and Demodex. Methods: This study included 144 patients (70 with acne vulgaris, 6 with pityriasis folliculorum, 15 with seborrheic dermatitis, 39 with rosacea, 8 with eczema, and 6 with perioral dermatitis) and 73 healthy subjects. We evaluated Demodex positivity using the standard superficial skin biopsy method in all groups. The presence of more than five Demodex mites per square centimeter was considered positive at the diagnosis. Results: Of the 144 patients included in the study, 107 (74.3%) were female, and 37 (25.7%) were male, while 40 (54.8%) of the 73 healthy subjects were female, and 33 (45.2%) were male. Twenty-one patients (14.5%) and five of the healthy subjects (6.8%) tested positive for Demodex. We found that Demodex positivity rates in the rosacea and acne vulgaris groups were higher than in the control group. However, this level was not statistically significant (p>0.05). We found the highest positivity rate among the patient groups in the pityriasis folliculorum (4/6, 66.7%), rosacea (8/39, 20.5%), and perioral dermatitis (1/6, 16.7%) groups. Lastly, we found no statistically significant relationship between the demographic and clinical characteristics of the groups and Demodex positivity (p>0.05). Conclusion: The present study is the only study that investigated Demodex positivity in six different dermatological diseases. Based on the results, we believe that investigating Demodex spp. positivity in dermatological diseases such as acne vulgaris, rosacea, and pityriasis folliculorum would be beneficial for early diagnosis and treatment.

The incidence of acute kidney injury and its association with mortality in patients diagnosed with COVID-19 followed up in intensive care unit.

INTRODUCTION: The kidneys are some of the most frequently affected organs during coronavirus disease 2019 (COVID-19). This multicenter study evaluated the incidence of and risk factors for acute kidney injury (AKI) in COVID-19 patients followed up in intensive care unit (ICU) and its association with mortality. METHODS: Three hundred twenty-eight patients diagnosed with COVID-19 and hospitalized in ICU were included. Risk factors associated with AKI and mortality were evaluated. RESULTS: Eighty-eight patients (27.9%) were diagnosed with AKI. AKI was significantly associated with older age, higher baseline creatinine level, lower albumin level, and coexistence of cardiovascular disease and chronic obstructive pulmonary disease. Mortality in the entire study group was significantly associated with AKI, older age, requirement of invasive mechanical ventilation, higher neutrophil level, lower lymphocyte, and albumin levels. CONCLUSION: AKI is frequently seen during the course of COVID-19 and is associated with high mortality. Identifying AKI-related risk factors appears essential in the management of COVID-19 patients.

Immunogenicity after CoronaVac vaccination

SUMMARY OBJECTIVE: This study aimed to investigate the seropositivity of CoronaVac-SinoVac vaccination in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) risk factors and comorbidities. METHODS: Immunoglobulin (IgG) antibody responses were examined on the 21st day after the second dose of CoronaVac-SinoVac 6 μg vaccine on the 28th day. SARS-CoV-2 IgG antibody levels were measured by using the enzyme-linked immunosorbent assay method in vaccinated health care workers (n=134) (Group I), vaccinated polymerase chain reaction (PCR) (+) who had coronavirus-19 (COVID-19) disease (n=21) (Group II), and unvaccinated PCR (+) (n=28) (Group III) participants. Subgroups were formed in Group I according to the presence of COVID-19 risk factors and comorbidities (diabetes mellitus, cardiovascular disease, and asthma/allergy) and demographic data. RESULTS: Seropositivity rates were 95.5, 100, and 89.3% for Groups I, II, and III, respectively. IgG antibody levels were found significantly higher in the group between the ages of 20-30 in group I compared to those aged 31-50 and over 50 (both p<0.01). It was found significantly higher in normal-weight individuals than in the overweight and obese group (both p<0.01). IgG antibody levels were found significantly lower in people with cardiovascular disease and diabetes mellitus compared with those who did not (p<0.05 and p<0.001, respectively). There was a negative correlation between IgG antibody response values and body mass index and age in Group I (r= −0.336, p<0.001 and r= −0.307, p<0.001, respectively). CONCLUSION: IgG antibody values decrease with age and with increasing body mass index. The presence of comorbidities (i.e., diabetes mellitus and cardiovascular disease) decreased COVID-19 IgG antibody values.

Curcumin-meropenem synergy in carbapenem resistant Klebsiella pneumoniae curcumin-meropenem synergy.

BACKGROUND AND OBJECTIVES: The frequency of multiple resistant bacterial infections, including carbapenems, is increasing worldwide. As the decrease in treatment options causes difficulties in treatment, interest in new antimicrobials is increasing. One of the promising natural ingredients is curcumin. It is known to be effective in bacteria such as Pseudomonas aeruginosa, Escherichia coli, Burkholderia pseudomallei through efflux pump inhibition, toxin inhibition and enzymes. However, because its bioavailability is poor, it seffectiveness occurs in combination with antibiotics. In the study, the interaction of meropenem and curcumin in carbapenemase producing strains of Klebsiella pneumoniae was tested. MATERIALS AND METHODS: Thirty-nine Klebsiella pneumoniae isolates, resistant to meropenem, were used in this study. From those 15 MBL, 6 KPC, 17 OXA-48 and 1 AmpC resistance pattern were detected by combination disk method. Meropenem and Curcumin MIC values were determined by liquid microdilution. Checkerboard liquid microdilution was used to determine the synergy between meropenem and curcumin. RESULTS: Synergistic effects were observed in 4 isolates producing MBL, 3 isolates producing KPC, 4 isolates producing OXA-48, and 1 isolates producing AmpC (totally 12 isolates) according to the calculated FICI. No antagonistic effects were observed in any isolates. CONCLUSION: Curcumin was thought to be an alternative antimicrobial in combination therapies that would positively contribute to the treatment of bacterial infection. The effectiveness of this combination should be confirmed by other in vitro and clinical studies.

Immunogenicity after CoronaVac vaccination.

OBJECTIVE: This study aimed to investigate the seropositivity of CoronaVac-SinoVac vaccination in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) risk factors and comorbidities. METHODS: Immunoglobulin (IgG) antibody responses were examined on the 21st day after the second dose of CoronaVac-SinoVac 6 µg vaccine on the 28th day. SARS-CoV-2 IgG antibody levels were measured by using the enzyme-linked immunosorbent assay method in vaccinated health care workers (n=134) (Group I), vaccinated polymerase chain reaction (PCR) (+) who had coronavirus-19 (COVID-19) disease (n=21) (Group II), and unvaccinated PCR (+) (n=28) (Group III) participants. Subgroups were formed in Group I according to the presence of COVID-19 risk factors and comorbidities (diabetes mellitus, cardiovascular disease, and asthma/allergy) and demographic data. RESULTS: Seropositivity rates were 95.5, 100, and 89.3% for Groups I, II, and III, respectively. IgG antibody levels were found significantly higher in the group between the ages of 20-30 in group I compared to those aged 31-50 and over 50 (both p<0.01). It was found significantly higher in normal-weight individuals than in the overweight and obese group (both p<0.01). IgG antibody levels were found significantly lower in people with cardiovascular disease and diabetes mellitus compared with those who did not (p<0.05 and p<0.001, respectively). There was a negative correlation between IgG antibody response values and body mass index and age in Group I (r= -0.336, p<0.001 and r= -0.307, p<0.001, respectively). CONCLUSION: IgG antibody values decrease with age and with increasing body mass index. The presence of comorbidities (i.e., diabetes mellitus and cardiovascular disease) decreased COVID-19 IgG antibody values.

[Investigation of Pseudomonas aeruginosa Biofilm Formation and Quorum Sensing Genes in Piperacillin/Tazobactam and Ciprofloxacin Sub-minimal Inhibitory Concentrations]. / TPiperasilin/Tazobaktam ve Siprofloksasin Sub-minimal Inhibitör Konsantrasyonlarinda Pseudomonas aeruginosa Biyofilm Olusumunun ve Quorum Sensing Genlerinin Arastirilmasi.

Pseudomonas aeruginosa is a non-fermentative, oxidase-positive, motile gram-negative bacillus widespread in nature. The virulence factors of P.aeruginosa including the ability to grow under minimal growth conditions, the widespread presence in nature, and the ability to form biofilms make P.aeruginosa a highly important bacterium along with its resistance mechanisms against many antibiotics. The ability to form biofilms increases the symptom severity in diseases caused by P.aeruginosa and causes difficulties in the treatment. The aim of this study was to investigate the effects of sub-minimal inhibitory concentrations (sub-MIC) of piperacillin/tazobactam (TZP) and ciprofloxacin (CIP) which are used for the treatment of P.aeruginosa infections on biofilm formation and to investigate the relationship between the severity of biofilm formation and Quorum Sensing (QS) genes. The study included 24 P.aeruginosa isolates from the culture collection of Medical Microbiology Laboratory of Gazi University Faculty of Medicine. MIC values of TZP and CIP antibiotics were determined by the microdilution method. The biofilm layers in the antibiotic-free medium and in the sub-MIC (MIC/2, MIC/4 ve MIC/8) concentrations of antibiotics were visualized by using a scanning electron microscope (SEM). The QS genes (lasI, lasR, rhlI, and rhlR) of the 24 isolates with known biofilm characteristics were identified via the amplification of chromosomal DNA by using PCR method. In the study, it was foundthat both antibiotics reduced biofilm formation in a dose-dependent manner in sub-MIC concentrations compared to the antibiotic-free condition and that MIC/2 was the concentration, which reduced the biofilm formation most. These results were further confirmed by viewing the SEM images. The QS genes lasI, lasR, and rhlI were detected in a total of 19 isolates with moderately strong and strong biofilm formation, the rhlR gene was detected in six of the strong biofilm-forming isolates, in four of the moderately strong biofilm-forming isolates, and in three of the weak biofilm-forming isolates, respectively. The investigation of the effects of sub-MIC concentrations of antimicrobials, used for the treatment of P.aeruginosa infections, on the biofilm formation of P.aeruginosa and the investigation and better understanding of the QS systems associated with biofilm production will allow for finding out new treatment approaches and offer different options in combating infections with high morbidity and mortality.

In vitro effects of Candida albicans and Aspergillus fumigatus on dendritic cells and the role of beta glucan in this effect.

BACKGROUND: Dendritic cells (DCs) are able to initiate and regulate the immune response to fungal infections. ß-glucan stimulates the immune system, modulating cellular and humoral immunity. It has a beneficial effect in fighting fungal infections. OBJECTIVES: We investigated the in vitro effect of C.albicans and A.fumigatus infection on human DCs. The cytokine levels were determined by ELISA. MATERIAL AND METHODS: Human PBMCs isolation was performed by Ficoll-hypaque density gradient centrifugation method. DCs maturation was analysed by using flow cytometry. The cytokine levels were determined by ELISA. RESULTS: DCs stimulated by C. albicans and A. fumigatus induced DC maturation by increasing CD80 and CD86 co-stimulatory molecules. DCs stimulated by fungi produced IL-8 and IL-12p70. Whereas IL-10 production from the stimulated DCs did not differ from uninfected DCs. Also, the addition of ß-glucan to the DCs stimulated by fungi promoted the activation and maturation of DCs. CONCLUSIONS: Our results suggest that DCs are capable of initiating an innate and adaptive immune response against fungal infections. In addition, ß-glucan can be used as a novel stimulator to DC-based vaccination against fungal infections.

Cytokine profile in murine toxoplasmosis.

OBJECTIVE: To investigate which cytokines are produced after acute infection of mice with Toxoplasma gondii (T. Gondii) RH strain. METHODS: Mus domesticus domesticus mice in infected group were inoculated with with highly virulent T. Gondii RH strain by intraperitoneally. Serum samples were obtained from infected and non-infected mice for cytokine levels for ELISA assay. RESULTS: The concentrations of tumor necrosis factor-α, interferon-γ, interleukin (IL)-10 and IL-12 in the cardiac blood sample of the infected mice were significantly higher than those in uninfected controls (P<0.05). The levels of transforming growth factor-1ß decreased in mice infected with T. gondii compared to those of the controls, the decrease was statistically significant (P<0.05). No significant difference was observed in levels of IL-4 between infected and healty control groups (P>0.05). CONCLUSIONS: According to our findings, immune response into T helper type 1 was predominant during acute T. gondii infection. Further characterization and purification of Toxoplasma molecule(s) implicated in the regulation of cytokines could lead to the development of new drug prospects to control Toxoplasma infection.

[Investigation of West Nile virus seroprevalence in healthy blood donors]. / Saglikli kan vericilerinde Bati Nil virusu seroprevalansinin arastirilmasi

West Nile virus (WNV) which is a flavivirus transmitted by mosquitos, may lead to asymptomatic infection, mild febrile illness or encephalitis. Many sporadic cases and major outbreaks of West Nile fever have been reported worldwide, however, WNV infections have not been well documented in Turkey. The aim of the present study was to determine the prevalence of past WNV infections in a population of blood donors. Blood samples were collected from donors with their informed consent. Samples were processed and tested for WNV IgG by enzyme-linked immunosorbent assay (ELISA) (Euroimmun, Germany) according to the manufacturer's guidelines. Demographic data of the donors were recorded. A total of 2821 serum samples were tested. Among them, 28 samples were found to be WNV IgG positive (0.9%) and 41 of them were indeterminate (1.4%). Thus a total of 69 objects were considered to have encountered WNV (2.4%). All of the IgG positive samples (n= 69) and randomly-selected negative samples (n= 60) were re-analysed for the presence of viral RNA by a commercial real-time reverse transcriptase PCR (LightMix® Kit West Nile Virus, TIBMolbiol, Germany). West Nile virus RNA was not found in any of the samples. In conclusion, our data have supported the results of other studies indicating the presence of WNV infection in Turkey. Further larger scale studies are necessary to evaluate the possible risks of WNV infections in our country in terms of blood banking.

Effects of Saccharomyces boulardii on cytokine secretion from intraepithelial lymphocytes infected by Escherichia coli and Candida albicans.

Saccharomyces boulardii (S. boulardii) is a probiotic and used in the prevention or treatment of diarrhoea. Saccharomyces boulardii has many mechanisms to protect the host against diarrhoeal pathogens. It might modulate the immune system. In this study, the influence of S. boulardii on the secretion of cytokines from intraepithelial lymphocytes (IELs) infected with Escherichia coli (E. coli) and Candida albicans (C. albicans) was investigated in vitro. Cytokine levels were determined by enzyme-linked immunosorbent assay. The secretion of proinflammatory cytokines such as interleukin (IL)-1beta was decreased in the infected IELs incubated with S. boulardii, but different from it, anti-inflammatory cytokine levels such as IL-4 and IL-10, however, were found to be higher. These findings demonstrated that S. boulardii may have protective effects against diarrhoeal pathogens by reducing the proinflammatory response.