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.
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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