The current study investigated the probable roles of the respiratory viruses, and dual infections during acute exacerbations of COPD. Since climate-dependent respiratory viral incidence patterns in Iran are often dissimilar, preparing a comprehensive global model of respiratory infections with seasonal details in different geographical zones might decrease the morbidity and mortality rate in exacerbations of COPD.

Porins were prepared from smooth strain of Salmonella typhi 0–901 and chemotype of rough mutant of S. typhimurium Ra‐30. Mice were immunized with both the porin preparations in different groups and challenged with S. typhimurium LT2–71 and S. enteritidis SH‐1269. Porin immunized mice showed significant protection (P <0.01) against challenge with homologous as well as heterologous strains. Hence, the use of porins may be attempted in future to protect against salmonellosis.

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Background: Biofilm formation is a major virulence factor in different bacteria. Biofilms allow bacteria to resist treatment with antibacterial agents. The biofilm formation on glass and steel surfaces, which are extremely useful surfaces in food industries and medical devices, has always had an important role in the distribution and transmission of infectious diseases. Objectives: In this study, the effect of coating glass and steel surfaces by copper nanoparticles (CuNPs) in inhibiting the biofilm formation by Listeria monocytogenes and Pseudomonas aeruginosa was examined. Materials and Methods:The minimal inhibitory concentrations (MICs) of synthesized CuNPs were measured against L. monocytogenes and P. aeruginosa by using the broth-dilution method. The cell-surface hydrophobicity of the selected bacteria was assessed using the bacterial adhesion to hydrocarbon (BATH) method. Also, the effect of the CuNP-coated surfaces on the biofilm formation of the selected bacteria was calculated via the surface assay. Results: The MICs for the CuNPs according to the broth-dilution method were ≤ 16 mg/L for L. monocytogenes and ≤ 32 mg/L for P. aeruginosa. The hydrophobicity of P. aeruginosa and L. monocytogenes was calculated as 74% and 67%, respectively. The results for the surface assay showed a significant decrease in bacterial attachment and colonization on the CuNP-covered surfaces. Conclusions: Our data demonstrated that the CuNPs inhibited bacterial growth and that the CuNP-coated surfaces decreased the microbial count and the microbial biofilm formation. Such CuNP-coated surfaces can be used in medical devices and food industries, although further studies in order to measure their level of toxicity would be necessary.

Common variable immunodeficiency (CVID) is a heterogeneous group of disorders characterized by hypogammaglobulinemia and increased susceptibility to recurrent pyogenic infections. This study was performed to subclassify CVID on the basis of the bactericidal antibody responses of patients to polysaccharide meningococcal vaccine. Twenty-five patients with CVID (18 male and 7 female) and 25 healthy volunteers received meningococcal polysaccharide vaccine A ؉ C. Serum bactericidal antibody (SBA) titers were measured at baseline and after 3 weeks. Response was correlated with clinical and immunological manifestations of CVID. Twenty-four (96%) of the 25 normal controls had a protective SBA titer of >8 postvaccination, whereas only 16 (64%) of the 25 CVID patients had a protective titer (P value ‫؍‬ 0.013). Among the patients with CVID who were nonresponders, there were significantly increased rates of bronchiectasis (P ‫؍‬ 0.008), splenomegaly (P ‫؍‬ 0.016), and autoimmunity (P ‫؍‬ 0.034) in comparison with patients who had protective SBA titers. A reversed CD4/CD8 ratio was more common in the nonresponder group of patients (P ‫؍‬ 0.053). We conclude that individuals with CVID who cannot produce protective postvaccination titers after receiving meningococcal polysaccharide vaccine are more likely to exhibit bronchiectasis, splenomegaly, and autoimmune diseases. Vaccination response may define subgroups of patients with CVID, enabling more effective monitoring and therapeutic strategies.Common variable immunodeficiency (CVID) is the most common symptomatic antibody deficiency and is characterized by hypogammaglobulinemia in the absence of any recognized genetic abnormality (8,13,21). CVID patients are susceptible to recurrent pyogenic infections (1, 8), as well as autoimmune and neoplastic diseases (6,17). Although infections of the respiratory and gastrointestinal tracts are common, some patients may present with meningitis (1, 8). Encapsulated organisms such as Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis are the most prominent pathogens in CVID patients (13,26).Despite attempts during recent decades to identify the underlying immune system defects in CVID, the pathogenesis of CVID remains unknown (26). Thus, the diagnosis of CVID is based on the genetic exclusion of other hypogammaglobulinemias that are well defined at the molecular level (11). Although the underlying pathophysiology of CVID is not clearly understood, a few general defects that lead to alteration of serum immunoglobulin concentrations have been described. Patients with CVID have a defect in B-cell differentiation that leads to impaired secretion of immunoglobulins. Additionally, several abnormalities of T cells have been reported in some patients (26).It has recently been shown that patients with CVID with loss of immunoglobulin M (IgM) memory B cells are susceptible to earlier onset of recurrent infections and more severe complications (5) than those with mild to moderate clinical manifestations. A number of other i...

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Salmonella enterica subsp. Typhi (S. Typhi) Vi antigen capsular polysaccharide (Vi-CPS) is a licensed vaccine against typhoid fever. As there is no animal model for S. Typhi fever to evaluate the protective efficacy of the Vi-CPS vaccine, a serum bactericidal assay (SBA) is the recommended 'gold standard' to evaluate its potency. Vi-CPS was extracted from S. Typhi Ty6S (CSBPI-B191) using a modified Gotschlich method. Purified Vi-CPS (50 mg) was injected intramuscularly into three groups of five rabbits; group 2 received an additional booster dose of 50 mg Vi-CPS on day 15 and group 3 received two additional boosters on days 15 and 30. The sera obtained from each group were tested by SBA on days 0, 15, 30 and 45. The anti-Vi-CPS titres for groups 1, 2 and 3 on days 15, 30 and 45 were 4, 16 and 16; 4, 32 and 32; and 16, 64 and 64, respectively. Thus, Vi-CPS was shown to be a potent immunogen, as even one dose could induce an efficient bactericidal effect against S. Typhi. Although Vi-CPS is a reliable vaccine, sometimes depolymerization during purification can affect its potency, which can be resolved through a potency test. As the passive haemagglutination test recommended by the World Health Organization does not indicate vaccine potency, we recommend using an SBA to evaluate the bactericidal ability of Vi-CPS.

Introduction: This study involved 300 Pseudomonas aeruginosa strains isolated from patients admitted in four Tehran hospitals. Using standard O-specific typing sera, they were all grouped into 16 strains out of 17 known P. aeruginosa. The strains were lyophilized and each was given a code according to the Collection of Standard Bacteria, Pasteur Institute of Iran (CSBPI) for further investigations. Methodology: Among all clinical samples, CSBPI: 16-190 was the most prevalent P. aeruginosa serotype which showed a high agglutination titer (4+, 320) against homologous O-specific typing sera. This serotype was selected for extraction of P. aeruginosa major outer membrane vesicles (OMP-F). OMP-F vesicles were extracted and purified according to the Deoxycholate Ultracentrifuge Differentiation Technique. Purity and molecular weight of OMP-F were determined by SDS-PAGE and the ability of OMP-F vesicles to induce high titers of antibody in rabbit, which was shown as a sharp antibody-antigen precipitation line in the agarose gel immune-diffusion technique. Results: Passive immunization of mice with anti-rabbit OMP-F antisera induced a high level of protection when the mice were postchallenged with 2×LD50 of live P. aeruginosa CSBPI: . Furthermore, active immunization of mice with 50 µg of OMP-F could protect mice against 2×LD50 of live homologous (100% protection) and 15 heterologous native Iranian P. aeruginosa serotypes with 50-100% level of protection. Conclusions: These investigations indicate that purified OMP-F of CSBPI: 16-190 can be regarded as a safe protective immunogen in vaccinothrapy against all P. aeruginosaimmunotype isolated in Iran.