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The impact of corruption on carbon emissions is one of the main objectives of empirical studies on environmental economics. Recently, a theoretical discussion was conducted on the significant impact of reducing the level of corruption on environmental quality in developing rather than in developed countries. In this study, an empirical investigation of this claim was conducted using panel data which included 61 countries, between 2003 and 2016. The effects of corruption on carbon emission were considered using a panel threshold model. The threshold variable included human development index (HDI) which divided countries into developing and developed ones endogenously. According to the results, the value of threshold (γ = 0.753) was consistent with the categorization of UNDP countries by HDI. In developing countries, for each unit of increase in the corruption index –which means a decrease in corruption levels– we observe a 0.08 unit decrease in carbon emission while carbon emission is no longer affected by the corruption levels in developed countries and decrease in corruption does not have a significant effect on carbon emission levels.

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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...

Some patients with common variable immunodeficiency (CVID) can generate an antibody response following vaccination with Neisseria meningitidis polysaccharide, but the duration of this protection is unknown. In this study, serum bactericidal antibody (SBA) responses to serogroup C N. meningitidis of 23 patients with CVID and 23 sex-and age-matched controls were measured 1 year after vaccination with the plain A/C meningococcal polysaccharide vaccine. The fold rise in serum bactericidal antibody geometric mean titers of the control group from prevaccination to 1 year postvaccination was significantly higher than that of the patient group (5.41-versus 2.96-fold, P ‫؍‬ 0.009). Of 23 CVID patients, 8 had a poor response to vaccine (<4-fold rise) 3 weeks after vaccination, and low titers remained when measured 1 year later. Of the 15 CVID patients who had a normal response to vaccine (>4-fold rise) 3 weeks after vaccination, 6 cases failed to maintain protective SBA titers, whereas the remaining 9 had protective titers 1 year after vaccination. Only one of the 23 controls, who developed protective SBA titers after 3 weeks, lost the protective titers after 1 year. Among the patients, the presence of bronchiectasis and/or splenomegaly at enrollment was associated with poor SBA response to vaccine at 3 weeks and/or failure to maintain protective levels at 1 year. The results of this study demonstrate that a number of CVID patients can produce protective antibody titers that can persist for 1 year after vaccination, which lends strong support to the inclusion of polysaccharide vaccine in the immunization program for CVID patients.

Brucellosis is a worldwide zoonosis and represents one of the most important public health problems in many countries, especially around the Mediterranean basin, Middle East, India and Central and South America. Currently subunit vaccines are being considered to develop effective vaccines for human which has been evidenced by vaccines currently available against the infections such as meningococcal diseases and influenza .The application of new adjuvants of microbial origins is also underway to design subunit vaccines promoting the immune responses to the antigenic determinant(s) of the vaccine. In order to explore the efficacy of Brucella abortus lipopolysaccharide (LPS) combined with different adjuvants and proteins (as a vaccine candidate) in the induction of immune response as an effective and long-lasting immunity against Brucella, we evaluated the outer membrane vesicle of Neisseria meningitidis serogroup B (GBMOMV) as a subcutaneous adjuvant and a part of a brucellosis candidate vaccine to induce high titres of specific anti-Brucella abortus S99 LPS in animal model (mice). The obtained results were compared with complete and incomplete Freund's adjuvants (CFA and IFA). LPS+GBMOMV was the most immunogenic compound that stimulated following the first injection an increase in IgG titre of about 3.90, 3.18 and 1.58 fold higher than that produced against LPS, LPS+IFA and LPS+CFA, respectively. The highest anti-LPS IgG titre was detected two weeks after the third injection (the day 42) of LPS+GBMOMV. Purified GBMOMV can be considered as a safe subcutaneous adjuvant and a part of a candidate vaccine when combined with lipopolysaccharide of Brucella abortus S99.

Protein antigens have drawn a lot of attention from investigators working on tuberculosis vaccines. These proteins can be used to improve the immunogenicity of the new generation BCG vaccines or even replace them completely. Recombinant technology is used to insure the production of pure mycobacterial antigens in high quantities. Mycolyl transferase 85B (Ag85B) is a potent, mycobacterial antigen that significantly stimulates immune responses. Since Ag85B is an apolar protein, production of the water-soluble antigen is of interest. In this work, we report a systematic optimization strategy concerning cloning systems and purification methods, aiming at increasing the yield of recombinant Ag85B. Our optimized method resulted in a yield of 8 mg of recombinant Ag85B from 1 liter of induced culture (400 μg/ml) by using pET32a(+), Escherichia coli Rosseta-gami™(DE3) pLysS and a Ni-NTA agarose-based procedure and on-column re-solubilization. The purified recombinant Ag85B showed strong immunostimulating properties by inducing high levels of TNF-α, IFN-γ, IL-12, and IgG2a in immunized mice, therefore it can effectively be applied in TB vaccine researches.

Background: Neisseria meningitidis Serogroup A, is a major cause of bacterial meningitidis outbreaks in Africa and the Middle East. While polysaccharide vaccines have been available for many years, these vaccines have many disadvantages including the induction of T-cell independent responses which do not induce memory responses. Objectives: Thus to overcome this problem, in this research outer membrane vesicle (OMV) containing PorA was extracted and evaluated by biological and immunological methods. Materials and Methods: OMVs were extracted with deoxycholate and EDTA, and purification was performed by sequential ultracentrifugation. Physicochemical properties of extracted OMVs were analyzed by electron microscopy and SDS-PAGE. The toxicity of LPS content in its was assayed by LAL test. The Presence of PorA as a major component of OMV was confirmed by western blot. To study antibodies synthesis after immunization with OMV, ELISA method was used. Also serum bactericidal assay (SBA) was performed to determine the serum bactericidal activity against N. meningitidis serogroup A. Results: The results revealed that the content of protein extracted was 0.1 mg/mL. The electron microscopy showed that intactness of the vesicle in these preparation ranged more than 70%. The SDS-PAGE showed that PorA as a major immunological part of outer membrane vesicle was located in 35-40kDa. LAL test showed that the endotoxin activity was around 126EU/mL which is safe for using. The ELISA test revealed that the IgG total titer was elevated after the first injection. SBA indicates that bactericidal antibodies rise after the second dose of booster. Conclusions: The results showed that the extracted OMVs were conformationally stable, and there were no pyrogenic determinants in OMV. Also the results showed that the OMV elicited high level of specific antibodies against N. meningitidis serogroup A. These results indicate that the OMV obtained here, can be used as a meningococcal vaccine after further investigation.