ABSTRACT
Pseudomonas aeruginosa is associated with different infections such as urinary tract infections (UTIs). The increased antibiotic resistance reaches the need to develop vaccine against the infections. In the present study, bioinformatics approaches were applied to design a novel multi-epitope of PcrV and OmpE from P. aeruginosa. The raised antibody against the multi-epitope was evaluated and challenge experiment was done to evaluate the efficacy of the multi-epitope. The results of epitope mapping of B-cells indicated 8 regions for PcrV and OmpE. The predicted 3D structure showed C-score = -1 and Z-score = -8.12. Molecular docking indicated high interaction between residues of Toll-like receptor 2 (TLR2) and TLR4 with the multi-epitope. The results of in silico simulation of the immune responses showed elevated levels of B-cell, T-cell, and memory cells. PcrV, OmpE, and the multi-epitope were expressed in pET28a-E. coli BL21 (DE3) and purified by Nickel columns. Our findings indicated that the sera collected from immunized rabbits with the multi-epitope reacted with the multi-epitope, PcrV, and OmpE in western blot. According to the ELISA results, the antibody developed against the multi-epitope showed cross-reactivity with individual proteins PcrV and OmpE. The level of antibody raised against the multi-epitope was significantly higher than the antibody reacted with PcrV or OmpE alone in ELISA. The challenge results confirmed that the load of bacteria was decreased in immunized rabbits as compared to the control. The results present the multi-epitope composed of PcrV and OmpE as a promising candidate against P. aeruginosa. Further evaluations are under investigation in animal model.Communicated by Ramaswamy H. Sarma.
ABSTRACT
We decided to examine suspected samples of pneumonia outbreak caused by the new coronavirus SARS-CoV-2 and provide information about the mortality rate due to this infection in different age groups in Iran. In this descriptive-cross-sectional study, a total of 784 samples of naso/oropharyngeal swabs of suspected patients with COVID-19 symptoms who had referred to Imam Khomeini, Shahid Fayaz-Bakhsh and Modarres hospitals in Tehran from February 24, 2020 to March 24, 2020 were examined by RT-PCR method. The highest incidence of the disease was within the age group of 50-59 years, while the lowest rate was in the 0-9 years age group. The highest rate of positive samples in terms of COVID-19 among suspected individuals was for patients >80 years of age (89%) and the highest mortality rate was in the age range of 70-79 years (31%) and >80 years (30), respectively. In terms of recovery, the highest rate was in the 30-39 years age group (65.2%). Statistical analysis showed that mortality significantly increased in the age group of >60 years old and in fact, mortality was significantly associated with older ages. According to the results of the current study, the prevalence of COVID-19 in lower age (0-9 years old) is lower and mortality rate is higher in older ages as significant increase in mortality was observed in those aged >60 years old. However, further epidemiological studies on a larger study population in different regions of Iran are needed to explain the prevalence, clinical features, and course of the disease.
ABSTRACT
Medial Tibial Stress Syndrome MTSS is frequently diagnosed as a severe clinical issue which occurs due to the cycle loadings (fatigue failure). Since the mechanical properties of the bones are random variables, therefore, there is a need for a probabilistic approach to rationally assess the reliability level of the fatigue failure of the tibia. The main contribution of this paper is to introduce a novel limit state function to determine the fatigue damage state and the reliability index of MTSS based on the different loading and aging conditions. In this study, the tibias of the several people at the different ages are subjected to the fatigue loadings. The load carrying capacities of the considered specimen are determined based on the reliability analysis. Indeed, several 3D finite element analyses are performed to find out the damage states of the tibias. Accordingly, the reliability-based stress analysis is accomplished to localize the most vulnerable zone of the bone. As it was expected, the higher loading cycles associated with the elder bones is related to the lowest fatigue reliability level. Finally, the target reliability level of MTSS is proposed to deliberate the safe level of the loading condition on the tibia in terms of the walking distance.
