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.

Investigation of Obesity-Related HAdV-36 in NAFLD Patients: a Case-Control Study.

BACKGROUND: HAdV-36 leads to adipocyte proliferation of adipose tissue through E4orf1 gene, leading to the development of obesity and related diseases. We aimed to investigate the presence and any association of HAdV-36 in non-alcoholic fatty liver disease (NAFLD) patients Methods: The patient group was composed of 116 patients; 30 obese patients with NAFLD (BMI > 30 kg/m2), 30 patients with Diabetes Mellitus (DM)+NAFLD (BMI > 30 kg/m2), 16 patients with NAFLD (BMI < 30 kg/m2), and operated obese group with NAFLD (BMI > 30 kg/m2). The control group comprised 81 non-obese healthy adults. Liver adipose tissue samples were obtained in 30 operated NAFLD patients. HAdV-36-DNA, HAdV-36 neutralizing antibodies, serum lipid, and adipokine levels were analyzed. RESULTS: HAdV-36 neutralizing antibodies (HAdV-36 Ab-positive) were detected in 10/116 and 2/81 participants in the study and control groups, respectively; the difference was statistically significant (p < 0.005). LDL, total cholesterol but not adipokine levels were found to be significantly higher in HadV-36 Ab-positive patients (p < 0.05). While HAdV-36 was identified as a risk factor with OR = 4.11 in univariate analyses, there was no significant difference in binary logistic regression analysis. HAdV-36-DNA was detected in the adipose tissue samples of two patients. CONCLUSIONS: We suggest that the presence of HAdV-36 may lead to the development of obesity with the increase in adipose tissue, and diseases such as hyperlipidemia, NAFLD, DM, and metabolic syndrome may develop on the basis of chronic inflammation caused by obesity. Thus, HAdV-36 may be a plausible risk factor for the development of NAFLD.

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.

Association of SARS-CoV-2 IgG Antibody Levels with Clinical/Laboratory Characteristics in COVID-19 Patients: Data from a Turkish Study.

BACKGROUND: COVID-19 causes clinical manifestations ranging from asymptomatic infection to multi-organ failure. It is reported that those with severe disease have higher anti-SARS-CoV-2 antibody titers compared to asymptomatic or mild cases. We evaluated the correlation of antibody responses with laboratory and clinical indicators in COVID-19 patients. METHODS: Seventy-nine male and 66 female patients (mean age: 39) with at least one positive SARS-CoV-2 RT-PCR test and SARS-CoV-2 IgG antibody result after acute infection were included. RESULTS: Seventy-six (52%), 45 (31%), and 24 (17%) patients had mild, moderate, and severe clinical findings, respectively. Patients with high body mass index and advanced age had significantly more severe disease (p < 0.001). A significant correlation was found between the increase in lymphopenia, C-reactive protein, ferritin, D-dimer, and lactate dehydrogenase and the severity of clinical findings (p = 0.0001). SARS-CoV-2 IgG antibody test was positive in 128 (88.3%) patients. A significant correlation was found between disease severity and antibody levels in the comparison of all groups (p < 0.001). CONCLUSIONS: Long-term monitoring of immune responses will be required to determine the appropriate time for the administration of new vaccines.

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.

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.

Helicobacter pylori-miRNA interaction in gastric cancer tissues: First prospective study from Turkey.

Helicobacter pylori (H. pylori) is involved in the etiology of gastric cancer (GC). miRNAs are short RNAs that regulate gene expression by marking mRNAs for degradation. miRNAs are involved in tumorigenesis, metastasis, and cell proliferation. We aimed to investigate the miRNA expression profiles of tissues from H. pylori (+) and (-) GC patients. Forty GC patients, 20 H. pylori (+) and 20 H. pylori (-), and a healthy control group were included. The miRNA expression levels were investigated by microarrays and quantitative RT-PCR. We detected 9 upregulated and 4 downregulated miRNAs by microarray. We selected 5 upregulated and 5 downregulated miRNAs for the quantitative RT-PCR assay. The relative fold changes of miRNAs in the cancerous tissue and non-tumor mucosa specimens of H. pylori (+) GC patients for hsa-miR-194 were 4.24- and 3.83-fold higher, respectively, whereas the hsa-miR-145 expression levels were downregulated 0.33-fold and 0.43-fold, respectively, in the same group. The presence of H. pylori significantly upregulated hsa-miR-194 and downregulated hsa-miR-145 expression levels in H. pylori (+) GC cases, compared to H. pylori (-) GC cases. Regional differences in the virulence of H. pylori strains may also be involved in the up- or downregulation of miRNA expression levels.

A Retrospective Analysis of Anaerobic Bacteria Isolated in 236 Cases of Pleural Empyema and their Prevalance of Antimicrobial Resistance in Turkey.

BACKGROUND: Parapneumonic effusions usually occur secondary to an infection and produce pus (empyema) that accumulates in the pleural space. We aimed to evaluate the prevalence of anerobes in patients with empyema and to assess their resistance patterns for seven antimicrobials. METHODS: Pleural fluid specimens from 236 patients were inoculated on Schaedler agar. Anaerobic bacteria were identified via API 20 A. Susceptibility testing for penicillin, ampicillin + sulbactam, amoxicillin + clavulanate, cefoxitin, clindamycin, metronidazole, and imipenem were performed with the E-test. RESULTS: There were 118 anaerobic bacterial strains detected in 66 (27.9%) of the 236 specimens. Gram-positive anaerobic cocci were detected in 54.23% and the predominant cocci were 41 Peptostreptococcus spp, (34.75%) followed by 17 P. acnes (14.41%) and 6 C. tertium (5.08%). The Gram-negative anaerobes were B. fragilis (28, 23.73%), P. melaninogenica (8, 6.78%), P. intermedia (4, 3.39%), F. nucleatum (6, 5.08%), F. mortiferum (5, 4.24%), and P. asaccharolytica (3, 2.54%). All anaerobic strains were susceptible to ampicillin + sulbactam, amoxicillin + clavulanate, and imipenem. The highest MIC was found to be > 256 µg/mL for penicillin in B. fragilis strains, 128 µg/mL for cefoxitin in P. melaninogenica strains, 32 µg/mL for clindamycin and 64 µg/mL for metronidazole in P. acnes strains. Clindamycin resistance was detected in 46.6% B. fragilis, and 17.6% for P. acnes. Thirty-eight (32.2%) strains produced beta-lactamase. CONCLUSIONS: The use of antimicrobial agents for thoracic empyema should be based on the isolated pathogens and their resistance profiles. Clinicians should be aware of the wide diversity of anaerobic genera and species in cases of pleural empyema.

Evaluation of Adenovirus-36 (Ad-36) antibody seropositivity and adipokine levels in obese children.

Adenovirus 36 (Ad-36) has recently been suggested as a possible contributor to the current obesity epidemic. The aim of this study was to investigate the prevalence of Ad-36 antibodies in obese children, as well as investigate the role of serum leptin and lipid levels in Ad-36-obesity. Seventy-one obese children and 62 non-obese children were included as the patient group (PG), including the healthy control group (HCG), respectively. Simultaneously, Ad-36 antibodies and adipokine levels were assessed with serum neutralization assays (SNA) and ELISA. Ad-36 antibody was detected in 9 patients (12.7%) and 1 patient (1.6%) in both the PG and HCG, respectively, while a significant difference was detected between groups (p < 0.05). Although serum LDL, total cholesterol, triglycerides and leptin levels were detected significantly higher, adiponectin level was detected paradoxically lower in the PG. However, a significant difference was not detected for lipids and leptin levels; adiponectin levels were found to be significantly lower in Ad-36 antibody-positive PG (p < 0.05). In conclusion, we suggest there is an association between Ad-36 and obesity in children, including IL-6 levels increasing in obese children with Ad-36 seropositivity. Conversely, adiponectin levels in obese children with Ad-36 seropositivity were higher. As such, there is a need for studies to understand the mechanisms underlying this observation.

The relationship of Chlamydophila pneumoniae with schizophrenia: The role of brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) in this relationship.

Several pathogens have been suspected of playing a role in the pathogenesis of schizophrenia. Chronic inflammation has been proposed to occur as a result of persistent infection caused by Chlamydophila pneumoniae cells that reside in brain endothelial cells for many years. It was recently hypothesized that brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) may play prominent roles in the development of schizophrenia. NT-3 and BDNF levels have been suggested to change in response to various manifestations of infection. Therefore, we aimed to elucidate the roles of BDNF and NT3 in the schizophrenia-C. pneumoniae infection relationship. RT-PCR, immunofluorescence and ELISA methods were used. Fifty patients suffering from schizophrenia and 35 healthy individuals were included as the patient group (PG) and the healthy control group (HCG), respectively. We detected persistent infection in 14 of the 50 individuals in the PG and in 1 of the 35 individuals in the HCG. A significant difference was found between the two groups (p<0.05). Twenty-two individuals in the PG and 13 in the HCG showed seropositivity for past C. pneumoniae infection, and no difference was observed between the groups (p>0.05). C. pneumoniae DNA was not detected in any group. A significant difference in NT-3 levels was observed between the groups, with very low levels in the PG (p<0.001). A significant difference in BDNF levels was also found, with lower levels in the PG (p<0.05). The mean serum NT-3 level was higher in the PG cases with C. pneumoniae seropositivity than in seronegative cases; however, this difference was not statistically significant (p>0.05). In conclusion, we suggest that NT-3 levels during persistent C. pneumoniae infection may play a role in this relationship.

The role of adenovirus 36 as a risk factor in obesity: the first clinical study made in the fatty tissues of adults in Turkey.

Obesity which developes due to multifactorial reasons, was associated recently with human Adenovirus-36 (Ad-36). The aim of this study was to investigate the prevalence of Ad-36 antibodies in obese adults and also to investigate the DNA of Ad-36 in their adipose tissue. In this cross-sectional and case-control based study, 49 obese adults, with BMI ≥ 30 kg/m(2), and 49 non-obese adults, with BMI ≤ 25 kg/m(2), applied for esthetic purposes and were included in this study as patient and control groups, respectively. Adipose tissue samples, obtained by the lipoaspiration method, were studied by single-step PCR and nested-PCR methods. Simultaneously, the presence of Ad-36 antibodies and serum leptin and adiponectin levels were assessed by serum neutralization assay (SNA) and ELISA, respectively. Serum samples which didn't cause a cytopathic effect at ≥ 1:8 were accepted as positive. Ad-36 antibody was detected in 6 (12.2%) of 49 patients by SNA and was statistically significant (p < 0.05). Ad-36 DNA was not detected in any of the adipose tissue samples of the patient or control groups. Mean BMI and leptin levels were higher in the Ad-36-positive group, while adiponectin levels were found to be lower in the Ad-36-positive group. Although no statistically significant difference was found in cholesterol and triglyceride levels between the two groups (p > 0.05), lower mean serum cholesterol and triglyceride levels were found in the Ad-36-positive patients. In conclusion, we couldn't detect Ad-36 DNA in adipose tissue; however, we detected significantly higher Ad-36 antibody levels in the obese group compared to the non-obese group, according to the both univariant and multivariant analyses, suggesting that Ad-36 may play a role in obesity. There is a need for new and extended serial, particularly cohort and human-based, studies in order to have a clear understanding of the Ad-36-obesity relationship.

Microorganisms in respiratory tract of patients diagnosed with atypical pneumonia: results of a research based on the use of reverse transcription polymerase chain reaction (RT-PCR) DNA microarray method and enzyme-linked immunosorbent assay.

BACKGROUND: Numerous molecular-based tests were applied for the laboratory-based diagnosis of viruses. In this cross-sectional case control study, in addition to bacteria, we aimed to determine respiratory viruses using, for the first time in our country, the Reverse Transcription PCR DNA Microarray method, and we also aimed to evaluate its diagnostic performance. METHODS: Respiratory viruses were investigated from nasopharyngeal swabs of 76 patients diagnosed with atypical pneumonia and 64 healthy controls using the CLART Pneumovir (Genomica, Spain) kit and from 10 mL blood samples of the same subjects. M. pneumoniae IgM was detected by ELISA and L. pneumophila IgM and C. pneumoniae IgM by indirect immunofluorescence. Person's chi-square test was used for statistical analysis. RESULTS: Our results showed that the specificity (100%) and the positive predictive value (100%) of the CLART Pneumovir kit were high, but its sensitivity (53%), its negative predictive value (64%), and its kappa value (50%) were low. Parainfluenza Virus type 3 and M. pneumoniae were found alone or together as the most common microorganisms while no cases of human bocavirus, adenovirus, rhinovirus, or coronavirus were detected. CONCLUSIONS: Our results demonstrated that, during the study period, most of our patients had atypical pneumonia due to Parainfluenza Virus type 3 and M. pneumoniae co-infection.

Humoral and Cellular Immunity to Severe Acute Respiratory Syndrome Coronavirus-2 Vaccination in Patients with Sarcoidosis

Background: The coronavirus disease 2019 vaccine induces both antibody and T-cell immune responses and has been proven to be effective in preventing coronavirus disease 2019, including its severe disease form, in healthy individuals. However, the details of severe acute respiratory syndrome coronavirus-2 immunoglobulin-G antibody responses and severe acute respiratory syndrome coronavirus-2 specific T-cell responses in patients with sarcoidosis are unknown. Aim: To measure and compare antibody responses and T cell responses using enzyme-linked immunosorbent assays and interferon-gamma release assay in sarcoidosis patients infected with coronavirus disease 2019 and vaccinated with CoronaVac. Study Design: A prospective cohort study. Methods: A total of 28 coronavirus disease 2019 polymerase chain reaction test-positive sarcoidosis patients who were infected with severe acute respiratory syndrome coronavirus-2 in the past 6 months and did not have coronavirus disease 2019 vaccination and 28 sarcoidosis patients who were administered with 2 doses of CoronaVac and never had coronavirus disease 2019 were included in this study. The immune response levels of patients were determined by measuring the severe acute respiratory syndrome coronavirus-2 immunglobulinG and interferon-gamma levels in the blood of the patients by the enzyme-linked immunosorbent assays method and interferon-gamma release assay tests, respectively. Results: The mean age of the patients in the COVID-infected group was 48.1 ± 11.3, while the mean age of the patients in the vaccinated group was 55.6 ± 9.32. The mean time elapsed after infection was 97.32 ± 42.1 days, while 61.3 ± 28.7 days had passed since the second vaccination dose. In the COVID-infected group, immunoglobulin-G and interferon-gamma release tests were positive in 64.3% and 89.3% of the patients, respectively. In the vaccinated group, immunoglobulin-G was positive in 10.7% of the patients, and interferon-gamma release test was positive in 14.3%. Conclusion: Innate immune responses are better than adaptive immune responses in patients with sarcoidosis. The coronaVac vaccine is insufficient to generate humoral and cellular immunities in patients with sarcoidosis.

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.

The detection of occult HBV infection in patients with HBsAg negative pattern by real-time PCR method.

AIM: Diagnostic problems may be encountered in Hepatitis B virus (HBV) infections by serological tests and HBV DNA can be detectable in plasma and liver tissue while the HBsAg test is negative. This situation can be defined as occult or isolated Anti-HBc infections. Occult HBV infections may be divided into two categories by using hepatitis markers. One of them being that all hepatitis markers are negative and the other situation is having Anti-HBc +/- and Anti-HBs+patterns. These situations can be seen in isolated Anti-HBc cases. METHOD: In this study, we aimed to detect the ratio of occult HBV infections by investigating HBV DNA in four different groups. These groups are: (1) 20 isolated Anti-HBc positive individuals, (2) 23 individuals naturally immune to HBV infection, (3) 20 individuals with seronegative hepatitis markers and high ALT levels, and (4) 23 vaccinated individuals against HBV. In order to detect HBV DNA the real-time PCR kit (QIAGEN, Artus HBV RG PCR Kit, Germany) with high analytical sensitivity (≤3.8IU/ml) was used. RESULTS: The reliability of the molecular methods was assessed by increasing the quantitation standards of internal, external and also positive controls. No HBV DNA was detected in any of the 86 individuals consisting of four study groups. CONCLUSION: In conclusion, we did not detect occult HBV infection in our four study groups by using a high sensitivity real-time (RT) PCR method, while occult HBV infections with various frequencies were detected in other large, serial international studies in which highly sensitive analytical molecular methods were used. Although we also used a high standard molecular kit to detect occult HBV infections, we suggest that the reason for the absence of detection of occult HBV infections may be due to the small number of cases included in this study. However, it was assumed that the use of a nucleic acid amplification technology (NAT) with high analytical sensitivity in blood banks to prevent HBV transmission by blood transfusion is controversial due to both costs and diagnostic efficacy and for this reason we suggest that it will be useful to perform large serial studies regarding occult HBV infections in the future.

The importance of transmission time in HIV infections and an epidemiological prospective follow-up study for 1 year in the Marmara Region of Turkey.

It is important to detect recent and new HIV/1 infections and to take preventative measures in order to prevent rapid disease progression in AIDS and to decrease the incidence of infection. We aimed to detect long standing or recent HIV infections by determining transmission times for the cases in which first-time HIV/1 seropositivity were detected. The serum samples of 323 cases which were found to be seropositive by ELISA and Western-blotting were included in this study. The discrimination between long-term and recent HIV/1 infection was made by determining transmission-time with the Aware BED-EIA, HIV-1 incidence test (IgG capture HIV-EIA) tests. Ninety-six healthy blood donors who did not have a positive anti-HIV test and a chronic infectious disease for at least 1 year were included in this study as a negative healthy control group. In the discrimination of long-term and recent HIV/1 infections, only in vitro ODn values were used. The cases with normalized optical density (OD) (OD(specimen)/OD(calibrator))<0.8 by commercial kit were accepted as recent HIV infection (155 days history or seroconversion less than 6 months). The cases with ODn >1.2 were accepted as long-term HIV/1 infections (more than 155 days history or more than 6 months). The cases with ODn between 0.8 and 1.2 were accepted as "additional tests needed" cases. We detected recent HIV/1 infections (<6 months) in 60 (18.5%) out of 323 cases and long-term HIV/1 infections (>6 months) in 263 (81.5%) out of 323 cases. The most frequently encountered transmission route in long-term and recent HIV/1 infections was heterosexual sexual intercourse as 54 (50%) and 257 (97%), respectively. 63.3% of newly infected patients were married females and 65.3% of recently infected patients were males. In conclusion, the detection of the high ratio of long-term HIV/1 infection cases (81.5%) compared to recent infections (18.5%) suggested to us, that the long standing cases may have some activities related with transmission of HIV/1 in the past. The detection of higher HIV/1-infections in individuals which had heterosexual sex and also in married males suggested that this situation poses a very great threat for the health of society.

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.

New approaches to in vitro diagnosis of hepatitis C infection a reason for post transfusion hepatitis: Diagnostic value of determination of hepatitis C virus core antigen.

In between the dates of February 2008-March 2009, by applying to Istanbul University CTF Microbiology and Clinical Microbiology Basic Sciences Branch and Duzen laboratories, 123 cases, where HCV RNA and anti-HCV positivity are identified with molecular (real-time PCR) and serologic (ELISA) methods as a positive control group, and 48 cases where HCV RNA and anti-HCV negativity are identified as a negative control group are established. The values of sensitivity, specificity, positive and negative approximation of recently developed HCV Core Ag (Abbott Diagnostics, Germany) kit are determined successively as 94.3%, 97.9%, 99.1%, 87%, 95.3% and 88%. Although the new HCV Ag assay is clearly not sensitive enough to replace HCV NAT it may serve as a valuable tool in the HCV diagnostic algorithm as it is able to pick up a great majority of anti-HCV and HCV RNA positive samples, thus allowing a timely and less expensive serological diagnosis of an active HCV infection. This may be an advantage for labs that do not have access to PCR easily.