Molecular characterization and functional analysis of the PilQ380-705: a novel secretin domain in Pseudomonas aeruginosa

Background: Type 4 pili [T4P] is an important virulence factor of Pseudomonas aeruginosa [P. aeruginosa]. T4P pass the outer membrane through a large oligomeric channel made of a single PilQ protein that is most highly conserved at their C-termini. To develop a functional vaccine that can be used in clinical application, the secretin domain of the PilQ [PilQ380-706] was produced as a recombinant protein

Methods: A 981 bp fragment of C-terminal of the pilQ secretin [pilQ1138-2118] from was designed into the prokaryotic expression vector pET28a. The presence of the pilQ1138-2118 gene in the recombinant construct [pET28a/pilQ] was assessed by double digestion and PCR. After transformation, expression of the recombinant PilQ was induced by addition of IPTG. The expressed recombinant protein was purified by a modified method using a HisTrap affinity column and finally confirmed by SDS-PAGE. The functional activities of the produced PilQ380-706 confirmed by Western blot analysis and twitching inhibition assay

Results: The PCR and enzymatic digestion results showed the presence of the pilQ1138-2118 gene in the construct. The protein electrophoresis showed that the molecular weight of the recombinant PilQ380-706 is approximately 37 kDa. The Western blot analysis confirmed the specificity of specific IgG against the PilQ380-706 protein. The PilQ380-706 protein showed high biological activity in all of these standard assays

Conclusion: Since, the PilQ380-706 protein plays an important role in the biogenesis of pili; and thus, the primary establishment of P. aeruginosa; it seems that it can be used as a candidate vaccine or an adjuvant in the future studies

[Treatment of distal radius fracture with percutaneous pinning and pin-in plaster with patients older than 60 years]

Background: Distal radius fractures are the most common fractures of upper limbs in adults and their treatment in older patients is difficult. There are different therapeutic methods. In this study we aim to compare the therapeutic outcome of distal radius fractures treated with pin-in plaster and percutaneous pinning in older patients

Methods: In this randomized clinical trial, 60 old patients including 40 female and 20 male between 60-85 years old with distal radius fractures were evaluated in two groups of pin-in plaster [n=30] and percutaneous pinning [n=30] for treatment outcome, radiographic changes, functional outcome and pain during 6 month after surgery

Results: Pin-in plaster group compared to percutaneous pinning had significantly better radiologic findings at the end of 6 month. Excellent functional results after 6 weeks were observed in 30% and 23.3% of pin-in plaster and percutaneous pinning groups, respectively [p=0.84], six months after surgery, excellent functional outcome were significantly higher in pin-in plaster group [83.3% vs. 50%, p=0.006]. Being painless has no significant difference between groups after 6 weeks [43.3% vs. 56.7%, p=0.54], however it was significantly higher in pin-plaster group after 6 months [93.3% vs. 50%, p=0.002]

Conclusion: Pin-in plaster method compared to percutaneous pinning had acceptable radiologic and functional outcome in old patients over 60 years old. Using this method as a simple method with high efficacy in treatment of distal radius fractures is recommended

[Diagnosis of Helicobacter pylori infection in stool specimen by PCR-ELISA of ureC gene]

Helicobacter pylori is to blame for one of the most common chronic infections in humans and can cause peptic ulcer, gastritis, duodenitis and non-ulcer dyspepsia. Developing a reliable test to detect the infection is of great importance. For a variety of reasons, the existing tests including the stool culture, biopsy, PCR, and urea breath test are not up to par. The PCR-ELISA test is a preferably specific and sensitive approach to detect Helicobacter pylori in stool specimen and biopsy. Sixty-seven stool samples were collected from 127 patients who had undergone gastrointestinal endoscopy and stomach biopsy at Hazrat Rasool Akram Hospital, of Iran University of Medical Sciences based in Tehran. DNA was extracted from the samples before they were subjected to PCR of ureC gene. PCR-ELISA test was conducted and the results were compared. Stool-PCR test 31 [46.1%] of the 67 patients in question were positive and the same test on biopsies showed that 34 patients [50.7%] were infected while the rest tested negative. But the PCRELISA test on stool samples suggested that 42 patients [62.6%] were infected, and the same test on biopsies showed that 47 patients [70.1%] were positive. The results of these tests showed that detection of Helicobacter pylori through PCRELISA test on stool samples has high specificity and sensitivity and could be used as initial test to detect Helicobacter pylori infection