Applying Immunoinformatics Methods to Identify Potential T and B Cell Epitopes in the CagA Protein of Helicobacter pylori

Background and Aim: Helicobacter pylori is not only identified as a leading cause of chronic active gastritis and peptic ulcer disease in humans, but also it is considered as a risk factor for the development of gastric adenocarcinoma and MALT lymphoma. This study aims to predict specific epitopes for the utility of designing peptide vaccine against H. pylori infection by targeting invasive, virulent and membrane associated proteins CagA. Materials and Methods: In the present study, various immunoinformatics approaches have been applied to design a potential epitope-based vaccine against H. pylori infection. For prediction of linear epitopes, the sequence of CagA was submitted to ABCpred, BCPREDS, Bcepred, Bepipred and Ellipro servers. DiscoTope 2.0 and B-pred servers were also used for the prediction of conformational epitopes. In addition, prediction of T-cell epitopes was carried out by CTLPred. Results: The obtained results demonstrated 277 conformational B-Cell epitopes in addition to predicted high score linear B and T cell epitopes in CagA protein. Conclusion: These predicted epitopes might be used to design a vaccine against H. pylori and thus, could be validated in model hosts to verify their efficacy as vaccine

Significant role of pyocyanin and exotoxin A in the pathogenesis of Pseudomonas aeruginosa isolated from hospitalized patients

Aim: Due to the importance of exotoxin A and pyocyanin in the pathogenicity of this bacterium, we decided to evaluate the prevalence of genes encoding these virulence factors in clinical isolates of P. aeruginosa. Materials and methods: In this study, 100 clinical isolates were collected and identified by conventional biochemical tests. The ability to produce pyocyanin was determined by culture in a specific liquid medium (GSNB) at 37°C. The DNAs of the bacteria were extracted by the SDS method and a PCR test was performed to identify the exoA, phzA1B1C1D1E1F1G1, phzM, and phzS genes. Results: In this study, 90 isolates were pyocyanin-producing in phenotypic test. Also, 96%, 98%, 92%, and 96% of the isolates carried exoA, phzM, phzS, and phzA1B1C1D1E1F1G1 genes, respectively. Interestingly, 2 isolates lacking the exoA gene did not have the phzM and phzS genes at the same time, but the other 2 isolates carrying all three gene loci required for pyocyanin synthesis. Also, among the strains that lacked the ability to produce pyocyanin, 2 isolates concurrently lacked the phzS and phzA1B1C1D1E1F1G1 genes and 2 isolates simultaneously lacked the phzM and phzS genes, while the 2 isolates did not carry only the phzS gene. The other 2 isolates did not contain only phzA1B1C1D1E1F1G1 operon. Conclusion: The presence of the phzA1B1C1D1E1F1G1 operon, along with the phzM and phzS genes, plays a significant role in the production of pyocyanin pigment. However, the high prevalence of exoA gene in this study indicates the importance of this factor for vaccine designing

Molecular Detection of ISAba2 among Carbapenem Hydrolyzing Class D β-Lactamasese Acinetobacter baumannii Strains Isolated from Patients in Tehran Hospitals

Background and Aims: Acinetobacter baumannii is an opportunistic pathogen that has acquired a high rate of antibiotic resistance. Identification of the major elements increasing the expression of resistance genes while having a role in their transmission, can help us control the A. baumannii infections. This study aimed to determine the prevalence of ISAba2 in A. baumannii strains which include group D beta-lactamase genes among hospitalized patients. Materials and Methods: From August 2014 to April 2015, 105 A. baumannii strains were collected from different clinical samples of patients in 5 hospitals in Tehran. The confirmation of strains was done by phenotypical tests and existence of blaOXA-51-like gene. Antibiotic susceptibility pattern of the isolates were performed by Disc Diffusion Test (DDT) and Minimum Inhibitory Concentration (MIC) according to the CLSI. ESBL producing strains were recognized with Combined Disc Diffusion Test (CDDT) while the presence of OXA genes and ISAba1and ISAba2 were analyzed using PCR reactions. Results: The result of this study showed that the highest and lowest rates of antibiotic resistance belonged to cefotaxim (100%) and colistin (99.05%), respectively. A total of 55 isolates (54.5%) were capable of producing ESBL. Unlike the blaOXA-58-like gene, which was not found in any of the isolates, blaOXA-51-like- was present among all the isolates.. Prevalence of blaOXA-23-like and blaOXA-24-like genes were 103 (98.09%) and 68 (64.76%), respectively and the frequency of ISAba1 and ISAba2 were 105 (100%) and 97 (92.36%), respectively. Conclusions: The existence of additional elements as effective factors, can increase the expression of resistance genes and, therefore, help them to be mobile and transmitted between bacteria. Determination of these elements is, therefore, necessary for controlling infections

Comparison of IgG and IgA Antibodies Titrations against Helicobacter Pylori in Urban and Rural Populations in Mazandaran Province

Background & objective: The infection caused by Helicobacter pylori (H. pylori) is one of the most common bacterial gastrointestinal diseases throughout the world. Based on the role of H. pylori in a variety of diseases such as gastrointestinal and lymphoma, present study is aimed to consider the concentration of IgA and IgG against H. pylori in both rural and urban populations and then its relationship with some demographic characteristics. Materials & Methods: In this descriptive study, 400 sera samples were collected from both genders at the Sari treatment- health center. After blood collection, the concentration of IgG and IgA against H. pylori was measured by ELISA kit. Results: There was no significant difference in antibodies titration between men and women. Approximately 18.5% of males and 16.5% of females were positive regarding to IgA and 70.2% of men and 66.7% of women were positive regarding to IgG. The mean of antibodies in rural populations (0.87±0.35) was significantly (p<0.001) higher than those in urban populations (0.78±0.41). The mean of antibodies in patients who had a history of gastrointestinal infection was significantly higher than others (p<0.05). Conclusion: Due to the high level of IgA and IgG antibodies in studied populations, especially in rural people, and lack of symptoms in patients, the screen of positive serologic populations can be helpful for the management and control of infections caused by H. pylori

How does COVID-19 vaccination affect long-COVID symptoms?

ObjectiveThe current study aimed to identify the association between COVID-19 vaccination and prolonged post-COVID symptoms (long-COVID) in adults who reported suffering from this condition.MethodsThis was a retrospective follow-up study of adults with long-COVID syndrome. The data were collected during a phone call to the participants in January-February 2022. We inquired about their current health status and also their vaccination status if they agreed to participate.ResultsIn total, 1236 people were studied; 543 individuals reported suffering from long long- COVID (43.9%). Chi square test showed that 15 out of 51 people (29.4%) with no vaccination and 528 out of 1185 participants (44.6%) who received at least one dose of any vaccine had long long- COVID symptoms (p = 0.032).ConclusionsIn people who have already contracted COVID-19 and now suffer from long-COVID, receiving a COVID vaccination has a significant association with prolonged symptoms of long-COVID for more than one year after the initial infection. However, vaccines reduce the risk of severe COVID-19 (including reinfections) and its catastrophic consequences (e.g., death). Therefore, it is strongly recommended that all people, even those with a history of COVID-19, receive vaccines to protect themselves against this fatal viral infection

Long long-COVID symptoms in association with the vaccination status of the participants^b'*'.

Long long-COVID symptoms in association with the vaccination status of the participantsb'*'.</p

STROBE statement-checklist of items that should be included in reports of <i>cross-sectional studies</i>.

STROBE statement-checklist of items that should be included in reports of cross-sectional studies.</p

Long long-COVID and vaccine study, Fars, Iran.

ObjectiveThe current study aimed to identify the association between COVID-19 vaccination and prolonged post-COVID symptoms (long-COVID) in adults who reported suffering from this condition.MethodsThis was a retrospective follow-up study of adults with long-COVID syndrome. The data were collected during a phone call to the participants in January-February 2022. We inquired about their current health status and also their vaccination status if they agreed to participate.ResultsIn total, 1236 people were studied; 543 individuals reported suffering from long long- COVID (43.9%). Chi square test showed that 15 out of 51 people (29.4%) with no vaccination and 528 out of 1185 participants (44.6%) who received at least one dose of any vaccine had long long- COVID symptoms (p = 0.032).ConclusionsIn people who have already contracted COVID-19 and now suffer from long-COVID, receiving a COVID vaccination has a significant association with prolonged symptoms of long-COVID for more than one year after the initial infection. However, vaccines reduce the risk of severe COVID-19 (including reinfections) and its catastrophic consequences (e.g., death). Therefore, it is strongly recommended that all people, even those with a history of COVID-19, receive vaccines to protect themselves against this fatal viral infection.</div

Inclusivity in global research.

ObjectiveThe current study aimed to identify the association between COVID-19 vaccination and prolonged post-COVID symptoms (long-COVID) in adults who reported suffering from this condition.MethodsThis was a retrospective follow-up study of adults with long-COVID syndrome. The data were collected during a phone call to the participants in January-February 2022. We inquired about their current health status and also their vaccination status if they agreed to participate.ResultsIn total, 1236 people were studied; 543 individuals reported suffering from long long- COVID (43.9%). Chi square test showed that 15 out of 51 people (29.4%) with no vaccination and 528 out of 1185 participants (44.6%) who received at least one dose of any vaccine had long long- COVID symptoms (p = 0.032).ConclusionsIn people who have already contracted COVID-19 and now suffer from long-COVID, receiving a COVID vaccination has a significant association with prolonged symptoms of long-COVID for more than one year after the initial infection. However, vaccines reduce the risk of severe COVID-19 (including reinfections) and its catastrophic consequences (e.g., death). Therefore, it is strongly recommended that all people, even those with a history of COVID-19, receive vaccines to protect themselves against this fatal viral infection.</div