The Role of Akkermansia muciniphila and Faecalibacterium prausnitzii in the Pathogenesis of Ulcerative Colitis and Crohn's Disease.

BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases with uncertain etiology. We aimed to determine the amounts of Akkermansia muciniphila and Faecalibacterium prausnitzii in the intestinal microbiota of these patients and to correlate their amounts with blood IL-8, IL-10, and IL-12 cytokine levels. METHODS: Thirty UC, 30 CDs, and 46 healthy controls were included. IL-8, IL-10, and IL-12 levels of blood samples were analyzed by ELISA. The amounts of Akkermansia muciniphila and Faecalibacterium prausnitzii were determined by the LightCycler 480 qPCR system. RESULTS: F. prausnitzii, A. muciniphila, IL-10, and IL-12 decreased in patient groups, while IL-8 decreased in UC but increased in CD. A significant difference was detected between the patient and control groups in terms of F. prausnitzii, A. muciniphila, and IL-8, but not for others. The amount of F. prausnitzii was correlated with IL-8 and IL-10 in UC and with IL-10 in CD patients. CONCLUSIONS: The decrease in the amount of F. prausnitzii was associated with the increase in UC disease severity. A. muciniphila and F. prausnitzii were detected in lower amounts in both diseases. F. prausnitzii decreased more with the severity of UC, suggesting that these bacteria may have complex roles in their etiopathogenesis.

The Role of Adenovirus-36 in Adults with Obesity-Induced Type 2 Diabetes.

BACKGROUND: Obesity may also develop due to a viral infection caused by adenovirus 36. We aimed to detect the presence of neutralizing antibodies against Ad-36 in adult patients who developed type 2 diabetes due to obesity (BMI ≥ 30 kg/m2). METHODS: The patient group (PG) was composed of 80 obese people with type 2 diabetes, the patient control group (PCG) was composed of 40 non-obese people with type 2 diabetes, and the healthy control group (HCG) was com-posed of 40 non-obese people without type 1 or type 2 diabetes in this case-control study. The presence of Ad-36 neutralizing antibodies was studied by serum neutralization assay. RESULTS: A significant difference was found between the PG and HCG in terms of Ad-36 antibody positivity (p < 0.0001) but no significant difference was detected between the PG and the PCG (p > 0.05). BMI, serum leptin, adiponectin, and triglyceride levels were significantly higher in the PG (p < 0.05). Conversely, TNF-α and IL-6 levels were significantly lower in the PG (p < 0.0001). When the two groups were compared, the mean levels of total cho-lesterol and LDL in the PG were found to be high, although not significant (p > 0.05). In type 2 diabetes patients (n = 120), age, BMI, HDL, LDL, triglyceride, total cholesterol, Ad-36 presence, leptin, adiponectin, TNF-α, and IL-6 parameters were taken as independent variables for logistic regression. While BMIs was found to be significant (odds ration [OR] = 2.358; p = 0.0001, 95% Cl 1.507 - 3.690, Ad-36 presence was found to be a significant (OR = 27.352; p = 0.003, 95% Cl 3.157 - 236.961). Our study showed that BMI and Ad-36 increase type 2 diabetes risk by 2.3 and 27.3-fold in the PG and PCG (type 2 diabetes patients) versus the HCG. There was also a significant difference between PCG and HCG. CONCLUSIONS: We suggest that Ad-36 seropositivity is also a risk factor for the development of type 2 diabetes independent of being obese.

[Evaluation of the Diagnostic Performance of SARS-CoV-2 Rapid Antigen Tests in COVID-19 Patients]. / SARS-CoV-2 Hizli Antijen Testlerinin COVID-19 Hastalarindaki Tanisal Performanslarinin Degerlendirilmesi.

The gold standard in the definitive diagnosis of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is nucleic acid amplification tests (NAAT) due to their high sensitivity and specificity in detecting viral ribonucleic acid. However, while leaving two years behind in the pandemic, resources have come to the point of exhaustion in terms of both the economy and the manpower working in the field of health services. Therefore, the need for rapid, simple and accurate tests to diagnose SARS-CoV-2 infection continues. In this study, it was aimed to compare the performance characteristics of SARS-CoV-2 rapid antigen tests (RAgT) in the diagnosis of coronavirus disease 2019 (COVID-19) cases with the real-time reverse transcription-polymerase chain reaction (rRT-PCR) method. In Istanbul University-Cerrahpasa Faculty of Medicine COVID-19 Molecular Diagnosis Laboratory, SARS-CoV-2 RNA positive respiratory tract samples with viral loads of <25 Ct (cycle of treshold), 25-29 Ct, 30-35 Ct and 35

Point Mutations at gyrA and gyrB Genes of Levofloxacin Resistant Helicobacter pylori Strains and Dual Resistance with Clarithromycin.

BACKGROUND: Spontaneous point mutations in genes encoding gyrA/B subunits of DNA gyrase are responsible for fluoroquinolone resistance. We aimed to determine the clarithromycin and levofloxacin resistance phenotypically in H. pylori strains and to investigate the mutations responsible for levofloxacin resistance and the effects of these mutations on dual antibiotic resistance. METHODS: A total of 65 H. pylori isolates were included. The E-test method was used for the clarithromycin and le-vofloxacin antimicrobial susceptibility test. Real-time PCR was used to detect the point mutations. RESULTS: Twenty-four (36.9%) of 65 H. pylori strains were phenotypically resistant to clarithromycin and 14 (21.5%) to levofloxacin. The phenotypic levofloxacin resistance rate of strains with Asn87Lys and Asp91Asn mutations were significantly higher (gyrA gene) (p < 0.05). The phenotypic levofloxacin resistance rate of strains with Arg484Lys and Asp481Glu mutations were significantly higher (gyrB gene) (p < 0.05). The Asn87Lys mutation increased the risk of phenotypes being resistant to levofloxacin 70.156 times and Asp91Asn mutation increased 125,427 times higher. Seven (10.8%) of 65 H. pylori strains showed dual resistance to both levofloxacin and clarithromycin. The rate of being dual resistant with A2143G mutation (clarithromycin resistance) was found to be significantly higher (p < 0.05). CONCLUSIONS: The Asn87Lys and Asp91Asn mutations in the gyrA gene had a phenotypically enhancing effect on levofloxacin resistance, while the presence of Asp481Glu and Arg484Lys mutations in the gyrB gene did not. The existence of dual resistance was developed with the increase in clarithromycin and levofloxacin resistance rates.

Epstein-Barr Virus and Helicobacter pylori co-infection in patients with gastric cancer and duodenale ulcer.

We aimed to detect EBV/Hp (Epstein-Barr Virus/Helicobacter pylori) co-infection by determining the number of copies of EBV/EBER-1 in the gastric biopsy samples of the Hp (+) GC, peptic ulcer (PU), and non-ulcer dyspepsia (NUD) cases. The patient group (PG), with 34 patients (34 GC and 30 PU patients) and a control group with 40 NUD cases were included. All patients and controls were Hp positive. EBV/EBNA-1 IgG were measured by the Anti-EBNA-1 ELISA IgG kit. Determination and quantification of EBV/EBER-1 gene region was performed by qPCR. EBV/EBER-1 positivity was 35.29% (12/34), 6.6% (2/30) and 2.5% (1/40) in GC, PU and 40 NUD cases, respectively. A significant difference was found between the GC and NUD cases (p=0.001). A significant difference was found between the groups for mean EBV/EBER-1 copy numbers (p=0.019). No significant difference was found between GC and the NUD cases (p=0.1455) for EBV/EBNA-1 IgG antibody positivity. EBV/EBER-1 positivity (OR=3.319), and age ≥55 years old (OR=2.331) were found to be a significant in multivariate logistic regression. In conclusion, our data suggest that the GC risk by EBVand Hp co-infection increased 3.3 times.

[Evaluation of the Diagnostic Performance of Different Principles of SARS-CoV-2 Commercial Antibody Tests in COVID-19 Patients]. / SARS-CoV-2 ile Ilgili Farkli Prensipli Ticari Antikor Testlerinin COVID-19 Hastalarindaki Tanisal Performanslarinin Degerlendirilmesi.

Following the emergence of severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) and using only PCR for diagnosis, antibody tests have been rapidly developed by various commercial companies. There are differences between the sensitivity and specificity of these tests due to the usage of different viral target proteins and antibody subclasses. In order to evaluate the diagnostic use of these tests, we aimed to examine the diagnostic performance, especially sensitivity and specificity, of SARS-CoV-2 IgM, IgA and IgG tests of various companies (Abbott, Roche, Euroimmun, Dia.Pro, Anshlabs, Vircell, UnScience and RedCell), which have different principles (ECLIA/CLIA, EIA, LFA). Current (n= 180) and past (n= 180) COVID-19 patients with clinical and molecular diagnosis of COVID-19 admitted to Istanbul University-Cerrahpasa, Cerrahpasa Faculty of Medicine Hospital, Pandemic Polyclinic with suspected COVID-19 infection, were included in our study. The patients admitted within the first 3 weeks after the onset of symptoms were included in the current patient group, and those admitted at the third and after the third week were included in the past patient group. Serum samples (n= 180) obtained from Istanbul Sisli Hamidiye Etfal Training and Research Hospital, Blood Center between April and June 2018 before the COVID-19 pandemic were included in the study as a control group. All the tests included in our study were studied with the recommendations of the manufacturer companies. Between the IgG detection tests with different principles in patients with past COVID-19, the sensitivity and specificity values of the most effective tests were; 86.7%/99.4% (Abbott), 86.1%/98.9% (Dia.Pro), 91.3%/95% (RedCell). Between the IgM detection tests with different principles in current COVID-19 patients, the sensitivity and specificity values were; 67.8%/99.4% (Abbott), 68.9%/98.6% (Vircell), 50%/97.5% (RedCell). Abbott IgM with a kappa coefficient of 0.67 and Vircell IgM + IgA test with a kappa coefficient of 0.65 showed the best fit in patients with current COVID-19 infection. In patients with past COVID-19, Abbott IgG with 0.86 kappa coefficient and Dia.Pro IgG test with 0.85 kappa coefficient showed the best match. Due to the low sensitivity of IgM detection antibody tests, they should not be preferred instead of real-time reverse transcriptase polymerase chain reaction in routine diagnosis. IgG detection tests may be preferred to detect the antibody response and the titers in people who have had COVID-19 for population seroprevalence and especially therapeutic immune plasma production. However, it is thought that the combined use of both ECLIA/CLIA-based and EIA/ELISA-based tests together may be more effective in routine use for SARS-CoV-2 IgG tests.

The Prevalence of Periodontal Pathogenic Bacteria in Atherosclerotic Cardiovascular Disease.

BACKGROUND: A possible link between periodontal pathogenic bacteria and atherosclerosis may exist based on the inflammatory mechanisms initiated by bacteria found in periodontal lesions. Our aim was to investigate the presence of DNA originating from T. denticola, C. rectus, T. forsythia, and P. gingivalis in the vascular tissue specimens obtained from patients who underwent surgery for arteriosclerotic vascular disease in this study. METHODS: A total of 96 patients diagnosed with valvular heart disease due to atherosclerosis and 85 patients with advanced aortic valve stenosis due to rheumatic fever and had undergone aortic valve replacement were included as the study (PG) and the control groups (CG), respectively. Atheroma plaques and vascular tissue specimens were collected from PG and CG during cardiovascular surgical procedures. Revitalization of the lyophilized T. denticola, ATCC 35405; C. rectus, ATCC 33238; P. gingivalis, ATCC 33277 and T. forsythia, ATCC 43037 strains was performed according to the manufacturer's instructions. C. rectus, T. forsythia, and T. denticola DNA samples were analyzed using the one-step in-house PCR method. RESULTS: In one (1.04%) and three (3.13%) out of 96 atherosclerotic PG tissue specimens, P. gingivalis and T. for-sythia DNA were detected, respectively. No T. denticola or C. rectus DNA was found in the study specimens. Periodontal pathogenic bacteria were not observed in 85 CG tissue specimens. There was no statistically significant difference between PG and CG for the presence of P. gingivalis and T. forsythia DNA using Fischer's Exact test (p > 0.05). CONCLUSIONS: In conclusion, with the case-control studies on a small scale such as in our study, it is not possible to determine a causality relationship between periodontal pathogenic bacteria and formation of atherosclerosis. Periodontal pathogenic bacteria may not be the only factor that causes inflammatory diseases associated with atherosclerosis. Host response and inflammatory mechanisms may be affected by other factors such as ethnicity, dietary habits, nutritional availability, and lifestyle. Taken together, it is difficult to conclude a causal link between periodontal pathogenic bacteria and formation of atherosclerosis.

The Relationship between Gastroduodenal Pathologies and Helicobacter pylori cagL (Cytotoxin-Associated Gene L) Polymorphism.

BACKGROUND: The polymorphisms in the region between 58 and 62 amino acids of the 194-amino acid CagL protein (CagL hypervariable motif) affect the binding affinity of CagL to integrin α5ß1 (ITGA5B1) receptor in host epithelial cells and have an effect on the development of various gastrointestinal diseases. We aimed to evaluate the associations of gastroduodenal pathologies, with the polymorphisms of cagL gene of Helicobacter pylori (H. pylori) and also associations between vacA genotypes and cagL polymorphisms. METHODS: A total of 19 gastric cancer, 16 duodenal ulcer, and 26 non-ulcer dyspepsia patients were included in this case-control study. All cases had H. pylori. A fragment of 651 bp from gene cagL (hp0539) and cagA, vacA genes was amplified by polymerase chain reaction. Purified polymerase chain reaction products were sequenced by Sanger sequencing, and nucleotide sequences were translated into amino acid sequences. RESULTS: All of the H. pylori strains had cagL and cagA genes. In the 16 (84%) gastric cancer cases, the D58 amino acid polymorphism was significant than the 4 (15.4%) duodenal ulcer cases (P = .029), and the D58/K59 amino acid polymorphism was significant in 12 (63.1%) of the gastric cancer cases than 1 (3.85%) duodenal ulcer case (P = .008). D58/K59 and DKIGQ (n = 10; 52.63%) were the most common polymorphisms in the gastric cancer and were associated with the vacA genotype s1/m2, respectively (P = .022 and P = .008). The D58/K59 amino acid polymorphism was found to have a significant Odds Ratio (OR) value of 8.9 (P = .0017) in multivariate logistic regression analysis. CONCLUSIONS: The risk of gastric cancer development is 8.9 times higher with D58/K59 polymorphism.

Evaluation of the Diagnostic Performance of a SARS-CoV-2 and Influenza A/B Combo Rapid Antigen Test in Respiratory Samples.

This study aimed to evaluate the performance characteristics of a rapid antigen test developed to detect SARS-CoV-2 (COVID-19), influenza A virus (IAV), and influenza B virus (IBV) (flu) compared with those of the real-time reverse transcription-polymerase chain reaction (rRT-PCR) method. One hundred SARS-CoV-2, one hundred IAV, and twenty-four IBV patients whose diagnoses were confirmed by clinical and laboratory methods were included in the patient group. Seventy-six patients, who were negative for all respiratory tract viruses, were included as the control group. The Panbio™ COVID-19/Flu A&B Rapid Panel test kit was used in the assays. The sensitivity values of the kit were 97.5%, 97.9%, and 33.33% for SARS-CoV-2, IAV, and IBV, respectively, in samples with a viral load below 20 Ct values. The sensitivity values of the kit were 16.7%, 36.5%, and 11.11% for SARS-CoV-2, IAV, and IBV, respectively, in samples with a viral load above 20 Ct. The kit's specificity was 100%. In conclusion, this kit demonstrated high sensitivity to SARS-CoV-2 and IAV for viral loads below 20 Ct values, but the sensitivity values were not compatible with PCR positivity for lower viral loads over 20 Ct values. Rapid antigen tests may be preferred as a routine screening tool in communal environments, especially in symptomatic individuals, when diagnosing SARS-CoV-2, IAV, and IBV with high caution.

Detection of A2143G, A2142C, and A2142G Point Mutations with Real-Time PCR in Stool Specimens from Children Infected with Helicobacter pylori.

Reports have indicated an increasing prevalence of clarithromycin resistance in children relative to adults. Thus, it is important to investigate primary clarithromycin resistance before therapy to avoid treatment failure. A2142G, A2143G, and A2142C point mutations in the peptidyltransferase region of the 23S ribosomal RNA (rRNA) of Helicobacter pylori (H. pylori) strains isolated from children with gastrointestinal symptoms and asymptomatic children were evaluated via real-time polymerase chain reaction (RT-PCR) using fecal DNA samples. The presence of H. pylori was determined using a fecal H. pylori antigen enzyme-linked immunosorbent assay (ELISA) kit from the stools of children (n = 543). A2143G, A2142C, and A2142G point mutations were detected via RT-PCR and confirmed by sequencing the 23S rDNA. Fecal H. pylori antigen testing was positive in 101 symptomatic (49) and asymptomatic (52) children. A significant difference was found between the 0-5- and 5-18-year-old groups in terms of the A2143G and A2142G point mutations (p = 0.001). The A2142C mutation was not detected. There was a significant difference in the A2143G mutation between the symptomatic and asymptomatic 5-18-year-old children (p = 0.019). Macrolides are frequently used to treat upper respiratory tract infections in children due to their selective pressure effect. We suggest that H. pylori strains carrying mutations in the 23S RNA subunit conferring clarithromycin resistance may lead to an intense inflammatory response in the gastric epithelial cells, allowing them to proliferate more rapidly and causing possible diarrhea, halitosis, or abdominal pain in children.

Relationship Between ABO Blood Types and Coronavirus Disease 2019 Severity.

Objectives: Severe Acute Respiratory Syndrome Coronavirus-2 infection spreads rapidly around the world. The blood groups are recognized to influence susceptibility to certain viruses.The aim of this research was to determine any potential role of the patients' ABO and Rh blood groups in both the acquisition and severity of coronavirus disease 2019 (COVID-19). As a growing global health problem, to find any marker for COVID-19 may help to identify high-risk individuals and ease the strain on health system. Methods: The patients who were hospitalized between March and August 2020 with a diagnosis of COVID-19 and had a documented ABO blood type in medical database were examined retrospectively. Patients were grouped as survivors (followed up in pandemic wards /or intensive care unit [ICU]) and non-survivors. Their ABO blood types were correlated with general population's blood types. The labaratory findings of patients were evaluated according to the blood types. Results: A total of 492 patients included, 233 (47.4%) were male. The mean age was 58.9±17.5. Data of ABO blood groups of 51966 individuals in general population was used as a control group; the number of the patients in Rh (-) blood type 0, were significantly lower than the control group (p=0.008). Among the whole patient group (survivors and non-survivors), Blood type A 210 (42%) was the most common and type AB 52 (10%) was the least common. However, no statistically significant difference was noted between survivors (pandemic wards/ICU) and non-survivors unlike the previous studies (p=0.514). No correlation was found between laboratory findings (Hemoglobin, red cell distribution width, platelet, white blood cell, lymphocyte, D-Dimer, C-reactive protein, ferritin) and ABO blood groups of COVID-19 patients (p>0.05). Conclusion: There was no association found between the ABO blood type and COVID-19 infection rate or disease severity. No evidence was noted to support the use of ABO blood type as a marker for COVID-19. Further efforts are warranted to better predict outcomes of hospitalized COVID-19 patients.

Antibody responses after two doses of CoronaVac of the participants with or without the diagnosis of COVID-19.

BACKGROUND: CoronaVac, an inactivated whole-virion vaccine against COVID-19, has been shown to be safe with acceptable antibody responses by various clinical trials. AIMS: The objective was to investigate the post-vaccination antibody levels of both symptomatic and asymptomatic healthcare workers with or without the diagnosis of COVID-19 in an emergency department (ED) of a hospital serving as a pandemic hospital. METHODS: This single-centred, prospective study was conducted on 86 participants who were working as nurse or doctor in the ED. The volunteers were older than 18 years and either positive or negative for either computed tomography (CT), real-time reverse transcription polymerase chain reaction (qRT-PCR), or both. Thirty days after the second dose of CoronaVac (3 µg), the antibody levels were chemiluminescent microparticle immunoassay. RESULTS: Mean age of all participants were 33.1 ± 9.1 years. The antibody levels in the qRT-PCR( +) and CT( +) groups were significantly higher than the qRT-PCR( -) and CT( -) groups, respectively (p < 0.05). In the CT( +)/qRT-PCR( +) group, the antibody level was significantly higher than the CT( -)/qRT-PCR( -) and CT( -)/qRT-PCR( +) or CT( +)/qRT-PCR( -) group (p < 0.05). On the other hand, antibody levels in the hospitalized group were significantly higher than in the non-hospitalized group (p < 0.05). A significant positive correlation was observed between the time elapsed after vaccination and antibody levels of the participants (r = 0.343; p = 0.000). CONCLUSION: In conclusion, antibody responses of recovered patients COVID-19 diagnosed by both CT and qRT-PCR were much robust than the patients diagnosed by either one of the techniques or undiagnosed/disease-free participants suggesting that severity of the disease likely contributes to the antibody responses after vaccination with CoronaVac.

Fibronectin within Sodium Alginate Microcapsules Improved Osteogenic Differentiation of BMMSCs in Dose Dependent Manner by Targeting SP7, OCN, CDK1, ZBTB16, and Twist1 Expression.

Purpose: Insoluble fibronectin as an extracellular matrix (ECM) protein has the potential to promote proliferation, differentiation, and migration of mesenchymal stem cells (MSCs). However, there is limited information about the effects of fibronectin various concentrations on bone marrow-derived MSCs (BMMSCs) function and differentiation. Methods: In this experimental study, using a gel injection device, BMMSCs were encapsulated in sodium alginate microcapsules containing 1.25% alginate, 1% gelatin, and fibronectin (0.01, 0.05, 0.1, and 0.2 µg/ml). MTT assay was used to examine the proliferation of BMMSCs. Also, BMMSCs apoptosis were analyzed using Annexin-V/PI staining and fluorescence activated cell sorting (FACS). Alkaline phosphatase (ALP) test was conducted to assess BMMSCs osteogenic differentiation potential. Finally, mRNA expression levels of the SP7, osteocalcin (OCN), Twist Family BHLH Transcription Factor 1 (Twist1), Peroxisome proliferator-activated receptor γ2 (PPARγ2), Cyclin-dependent kinase 1 (CDK1), and Zinc Finger and BTB Domain Containing 16 (ZBTB16), following exposure with fibronectin 0.1 µg/ml. Results: According to results, fibronectin had the potential to promote proliferation rates of the BMMSCs, in particular at 0.1 and 0.2 µg/ml concentrations. we showed that the fibronectin was not able to modify apoptosis rates of the BMMSCs. ALP test results approved the notable potential of the fibronectin, to trigger osteogenic differentiation of the BMMSCs. Also, RT-PCR results indicated that fibronectin 0.1 µg/ml could augment osteogenic differentiation of cultured BMMSCs through targeting of OCN, SP7, Twist1, CDK1, and ZBTB16, strongly or slightly. Conclusion: Results showed that fibronectin can improve proliferation and osteogenic differentiation of BMMSCs without any effect on these cells' survival.

Comparison of SARS-CoV-2 Antibody Levels after a Third Heterologous and Homologous BNT162b2 Booster Dose.

This study aimed to determine the anti-S (receptor binding protein) RBD IgG antibody titers formed against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) and the neutralizing antibody inhibition percentages (nAb IH%) in blood samples taken after two doses of inactive or mRNA-based vaccine and a booster dose. Volunteers with two doses of inactivated CoronaVac (heterologous group; n = 75) and BioNTech (BNT)162b2 mRNA vaccine (homologous group; n = 75) were included in this study. All participants preferred the BNT162b2 vaccine as a booster dose. First, peripheral blood samples were taken 3 months after the second vaccine dose. Second, peripheral blood samples were taken 1 month after the booster dose. Anti-S-RBD IgG titers were determined by CMIA (SARS-CoV-2 IgG II Quant). Neutralizing antibodies were detected by a surrogate neutralization assay (SARS-CoV-2 NeutraLISA, Euroimmun, Lübeck, Germany). The median age of the volunteers was 40 (IQR 29-47) years old. After the heterologous booster dose, anti-S-RBD IgG levels and neutralizing antibodies increased approximately 50-fold and 9-fold, respectively. Anti-S-RBD IgG titers increased by 9 and 57 times, respectively, while nAb IH% increased by 1.5 and 16 times, respectively, among those with heterologous reminder doses and those with and without a prior history of coronavirus disease (COVID-19). This study showed that after the administration of a heterologous booster dose with BNT162b2 to those whose primary vaccination was with inactivated CoronaVac, the binding and neutralizing antibody levels were similar to those who received a homologous BNT162b2 booster dose. It was observed that the administration of heterologous and homologous booster doses resulted in the development of similar levels of neutralizing antibodies, independently from a prior history of COVID-19.

Anti-SARS-CoV-2 IgG and Neutralizing Antibody Levels in Patients with Past COVID-19 Infection: A Longitudinal Study

Background: Monitoring the longevity of immunoglobulin G (IgG) responses following severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections is vital to understanding the role of antibodies in preventing infection. Aims: To determine the quantitative IgG responses specific to the Spike-S1 (S1) receptor-binding domain (S1/RBD) region of the virus in serum samples taken between 4 weeks and 7 months after polymerase chain reaction (PCR) positivity in patients who are diagnosed with coronavirus disease-2019 (COVID-19). Study Design: A longitudinal study. Methods: This study included 113 patients with a clinical and molecular diagnosis of COVID-19. The first and second serum samples were taken 1 and 7 months, respectively, after the PCR positivity. S1/RBD-specific IgG antibody response was assayed using anti-SARS-CoV- 2 QuantiVac ELISA (IgG) kit (Euroimmun, Lübeck, Germany). The neutralizing antibodies were investigated in 57 patients whose IgG test results were above the cut-off value. Results: In 57 patients with SARS-CoV-2 IgG, the anti-SARS-CoV-2 IgG quantitative antibody levels significantly decreased after 7 months (Z = −2.197, p = 0.028). A correlation was detected between the anti-SARS-CoV-2 IgG and nAb percent inhibition (IH%) levels detected in 1 month (rs = 0.496, p < 0.001), but without significant correlation in serum samples taken on 7 months. The nAb IH% levels of the first and second were compared for COVID-19 severity and revealed no statistical difference (p = 0.256). In the second serum sample, the nAb IH%s of patients with moderate COVID-19 showed a statistically significant difference from patients with mild COVID-19 (p = 0.018), but without significant differences between severe and moderate or mild COVID-19. Conclusion: SARS-CoV-2 quantitative IgG antibody titers are significantly reduced at long-term follow-up (> 6 months). Due to the limited information on seroconversion, comprehensive studies should be conducted for long-term follow-up of the immune response against SARS-CoV-2.

Development of in House ELISAs to Detect Antibodies to SARS-CoV-2 in Infected and Vaccinated Humans by Using Recombinant S, S1 and RBD Proteins.

(1) Background: The aim of this study was to produce in-house ELISAs which can be used to determine SARS-CoV-2-specific antibody levels directed against the spike protein (S), the S1 subunit of S and the receptor binding domain (RBD) of S in SARS-CoV-2 vaccinated and infected humans. (2) Methods: Three in-house ELISAs were developed by using recombinant proteins of SARS-CoV-2, namely the S, S1 and RBD proteins. Specificity and sensitivity evaluations of these tests were performed using sera from SARS-CoV-2-infected (n = 70) and SARS-CoV-2-vaccinated (n = 222; CoronaVac vaccine) humans in Istanbul, Turkey. The analyses for the presence of SARS-CoV-2-specific antibodies were performed using the in-house ELISAs, a commercial ELISA (Abbott) and a commercial surrogate virus neutralization test (sVNT). We also analyzed archival human sera (n = 50) collected before the emergence of COVID-19 cases in Turkey. (3) Results: The sensitivity of the in-house S, S1 and RBD ELISAs was found to be 88.44, 90.17 and 95.38%, while the specificity was 72.27, 89.08 and 89.92%, respectively, when compared to the commercial SARS-CoV-2 antibody test kit. The area under curve (AUC) values were 0.777 for the in-house S ELISA, 0.926 for the S1 ELISA, and 0.959 for the RBD ELISA. The kappa values were 0.62, 0.79 and 0.86 for the S, S1 and RBD ELISAs, respectively. (4) Conclusions: The in-house S1 and RBD ELISAs developed in this study have acceptable performance characteristics in terms of sensitivity, specificity, AUC and kappa values. In particular, the RBD ELISA seems viable to determine SARS-CoV-2-specific antibody levels, both in infected and vaccinated people, and help mitigate SARS-CoV-2 outbreaks and spread.

Association between human leukocyte antigen gene polymorphisms and multiple EPIYA-C repeats in gastrointestinal disorders.

BACKGROUND: Polymorphisms of human leukocyte antigen (HLA) genes are suggested to increase the risk of gastric cancer (GC). AIM: To investigate the HLA allele frequencies of patients with GC relative to a control group in terms of CagA+ multiple (≥ 2) EPIYA-C repeats. METHODS: The patient group comprised 94 patients [44 GC and 50 duodenal ulcer (DU) patients], and the control group comprised 86 individuals [(50 non-ulcer dyspepsia patients and 36 people with asymptomatic Helicobacter pylori (H. pylori)]. Polymerase chain reaction was performed for the amplification of the H. pylori cagA gene and typing of EPIYA motifs. HLA sequence-specific oligonucleotide (SSO) typing was performed using Lifecodes SSO typing kits (HLA-A, HLA-B HLA-C, HLA-DRB1, and HLA-DQA1-B1 kits). RESULTS: The comparison of GC cases in terms of CagA+ multiple (≥ 2) EPIYA-C repeats showed that only the HLA-DQB1*06 allele [odds ratio (OR): 0.37, P = 0.036] was significantly lower, but significance was lost after correction (Pc = 0.1845). The HLA-DQA1*01 allele had a high ratio in GC cases with multiple EPIYA-C repeats, but this was not significant in the univariate analysis. We compared allele frequencies in the DU cases alone and in GC and DU cases together using the same criterion, and none of the HLA alleles were significantly associated with GC or DU. Also, none of the alleles were detected as independent risk factors after the multivariate analysis. On the other hand, in a multivariate logistic regression with no discriminative criterion, HLA-DQA1*01 (OR = 1.848), HLA-DQB1*06 (OR = 1.821) and HLA-A*02 (OR = 1.579) alleles were detected as independent risk factors for GC and DU. CONCLUSION: None of the HLA alleles were detected as independent risk factors in terms of CagA+ multiple EPIYA-C repeats. However, HLA-DQA1*01, HLA-DQB1*0601, and HLA-A*2 were independent risk factors with no criterion in the multivariate analysis. We suggest that the association of these alleles with gastric malignancies is not specifically related to cagA and multiple EPIYA C repeats.

Association between polymorphisms in HLA-A, HLA-B, HLA-DR, and DQ genes from gastric cancer and duodenal ulcer patients and cagL among cagA-positive Helicobacter pylori strains: The first study in a Turkish population.

Colonization of the human gastric mucosa by H. pylori may cause peptic and duodenal ulcers (DUs), gastric lymphomas, and gastric cancers. The cagL gene is a component of cag T4SS and is involved in cagA translocation into host. An association between the risk of gastric cancer and the type of HLA class II (DR and/or DQ) was suggested in different populations. The aim of this study was to investigate, the clinical association of the cagL gene with host HLA alleles in H. pylori strains that were isolated from patients with gastric cancer, DU, and non-ulcer dyspepsia (NUD) and to determine the HLA allele that confers susceptibility or resistance for the risk of gastric cancer and DU development in Turkish patients. A total of 94 patients (44 gastric cancer and 50 DU patients; 58 male, 36 female; mean age, 49.6 years), and 86 individuals (50 NUD patients and 36 persons with normal gastrointestinal system [NGIS]; 30 male, 56 female; mean age, 47.3 years) were included as the patient and the control groups, respectively. CagA and cagL were determined by PCR method. DNA from peripheral blood samples was obtained by EZ-DNA extraction kit. For HLA SSO typing, LIFECODES SSO Typing kits (HLA-A, HLA-B HLA-C, HLA-DRB1 and HLA-DQA1/B1 kits) were used. The CagL/CagA positivity distribution in the groups were as follows: 42 (95.4%) gastric cancer, 46 (92%) DU and, 34 (68%) NUD and no NGIS cases. The HLA-DQA1*01 (OR: 3.82) allele was significantly different, suggesting that these individuals with H. pylori strains harbouring the CagL/CagA positivity are susceptible to the risk of gastric cancer and DU, and the HLA-DQA1*05 (OR, 0.318) allele was suggested as a protective allele for the risk of gastric cancer and DU using univariate analyses. HLA-DQA1*01 (OR, 2.21), HLA-DQB1*06 (OR, 2.67), sex (male, OR, 2.27), and CagL/CagA/(<2) EPIYA C repeats (OR, 5.72) were detected independent risk factors that increased the risk of gastric cancer and DU using multivariate analyses. However, the HLA-DRB1*04 (OR, 0.28) allele was shown to be a protective allele, which decreased the risk of gastric cancer and DU. Gastric pathologies result from an interaction between bacterial virulence factors, host epigenetic and environmental factors, and H. pylori strain heterogeneity, such as genotypic variation among strains and variations in H. pylori populations within an individual host.

Evaluating the effectiveness of anti-tuberculosis treatment by detecting Mycobacterium tuberculosis 85B messenger RNA expression in sputum.

BACKGROUND: The antigen 85 complex (85B) is secreted in large quantities from growing mycobacteria and the presence of bacterial mRNA is an indicator of cell viability. The quantitative detection of 85B mRNA expression levels can be used to assess the success of anti-tuberculosis treatment outcomes to detect viable mycobacteria cells. Therefore, we evaluated the levels of 85B mRNA of Mycobacterium tuberculosis strains in patients with pulmonary tuberculosis. METHODS: Thirty patients with primary tuberculosis were included in this study. The sputum specimens of patients were collected on days 0, 15, and 30 days and were cultured and evaluated by 85B mRNA-based RT-qPCR. RESULTS: Overall, 23 of the studied tuberculosis strains were susceptible to the primary anti-tuberculosis antibiotics used in this study, 7 were resistant. By the 30th day of treatment, 85B mRNA was detected in only one of the susceptible strains, but in all 7 of the resistant strains, though the relative gene expression varied between the strains. This difference between the susceptible and resistant strains at day 30 was statistically significant (p < 0.05). CONCLUSION: 85B mRNA expression levels could be used to follow up on primary tuberculosis cases. 85B mRNA seems to be a good diagnostic marker for monitoring anti-tuberculosis treatment outcomes.

Evaluation of the possible involvement of Ad-36-induced adipogenesis and coronary artery disease development in mediastinal adipose tissue samples.

Mediastinal fat has been suggested to be associated with cardiovascular diseases such as carotid stiffness, atherosclerosis and coronary artery calcification. We investigated the possible role of Ad-36-induced obesity in the pathogenesis of the coronary artery disease (CAD). Ad-36 DNA was investigated in the anterior mediastinal fat tissue samples of obese adults with CAD. Seventy-five obese adults with left main coronary artery (LMCA) disease, 28 non-obese adults with valvular heart diseases, and 48 healthy individuals without cardiovascular problems were included as the obese patient group (OPG), non-obese patient group (NOG) and healthy control group (HCG), respectively. We also simultaneously investigated Ad-36 antibodies by serum neutralization test (SNA), and measured leptin and adinopectin levels. Ad-36 antibodies were detected only in 10 patients (13.3%) within the 75 OPG. A statistically significant difference was detected between OPG, NOG and HCG in terms of Ad-36 antibody positivity (p>0.05). Ad-36 DNA was not detected in mediastinal tissue samples of OPG and NOP without PCR inhibitors. We suggest that Ad-36 may not have an affinity for mediastinal adipose tissue in obese patients with left main CAD and valvular heart diseases. Ad-36 antibody positivity results are not sufficient to reach a causal relationship.