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Abstract Introduction: Application of crude hydatid (HCF) cyst fluid antigen for the diagnosis of cystic hydatid (CH) is a method which along with immediate serological investigation can be helpful and effective in rapid treatment of the disease. However, there is no standard, highly sensitive, and specific serological test for antibody detection in cases of human CE yet. The current study aimed to evaluate the cross- reactivity of human IgG against human crude hydatid fluid antigens compared to B fraction of sheep cystic fluid antigen in order to find the target antigens with the highest IgG class, IgG subclass. Materials & Methods: This is an analytical case-control study using human crude HCF as the source of antigen for performing ELISA and Western blotting. Sample sera used in present work were collected from patients who recently had hydatid surgery in hospitals of Tehran, Hamadan and Ilam cities as human case group together with some human or animal sera with no history of hydatidosis with negative HCF using ELISA and IFAT as control group. Briefly, the required antigen was extracted and prepared from human hydatid fluid cysts. 30 positive samples sera from human sources were used as the case together with 30 healthy sera as control group. Hydatid cyst fluid antigen preparation was carried out according to the procedure described by Mamuti, et al, with slight modifications. ELISA method was carried out as described by Verastegui. Findings: The highest mean OD value in response to human HCF antigen was related to IgG4, while the lowest to IgG3. The sensitivity and specificity of ELISA test used for evaluating the responses of human total IgG to HCF antigen were 100 and 95.8% respectively. Cross-reaction of human IgG class and subclasses responses was found for both antigens with the best reaction against human HCF antigen compared to antigen B using a ratio of mean OD value to each antigen divided by the cut-off point value for the same antigen. Discussion & Conclusion: Human sera showed a considerable cross-reactivity against human HCF antigens and antigen B by ELISA test. The best human IgG subclass response against all antigens was found to be IgG4.

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Introduction: Visceral Larva Migranas (VLM) is a zoonotic disease caused by the migration of Toxocara canis or Toxocara cati larva in human tissues. This study was performed to evaluation of indirect immunofluorescent antibody (IFA) and ELISA in diagnosis of visceral larva migranas followed by a seroepidemiological survey in Tabriz. Materials & Methods: In this cross-sectional study, 558 persons from 2-20 years old selected from Tabriz in 2009-2010. Venous blood samples were collected and transferred to the research laboratory. Toxocara antibodies were detected by ELISA and IFA methods. We used the chi-square test for statistical analysis. Findings: Of 558 samples (235 male and 323 female) 162(29.04%) had anti-Toxocara antibodies and 396(70.96%) were negative. 162 samples were seropositive by ELISA, whereas anti-Toxocara antibodies were detected in 161 samples by IFA method. Discussion & Conclusion: The results of this study showed that, the IFA test have well efficiency for detection of VLM, but requires a laboratory equipped and trained personnels, While the ELISA test, is a simple and easy for the diagnosis and seroepidemiological study of toxocariasis.

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Introduction: Toxoplasmosis is one of the most common infectious diseases in the world and it caused by an intracellular protozoan called Toxoplasma gondii. This parasitic infection is usually asymptomatic in adults, but it become complicated if fetus infection occurred. This study aimed to determine the prevalence and incidence of toxoplasmosis in pregnant women in Babol, northern Iran. Materials and Methods: In this cross-sectional study during the years 2012-2013, 175 pregnant women in the first trimester of their pregnancy participated. Two ml blood was obtained from each participant and serum was separated. Then, anti-Toxoplasma antibodies were measured using ELISA method. Participants' demographic information and the risk factors were collected by questionnaire. Anti-Toxoplasma antibodies were measured in the second and third trimesters of pregnancy for who attended to the study. Results: The mean of age was 27.4 ± 9.5 years. 106 cases (60.6 %) had anti- Toxoplasma gondii antibodies (IgG) and 64 women (36.6 % ) had no specific antibody. The prevalence of infection was different in relation with age and location, but the difference is not statistically significant (p >0.05). Also, a statistically significant difference between prevalence of infection and other risk factors, such as abortion was not demonstrated. No case of acute Toxoplasma infection in the mother or congenital toxoplasmosis was reported. Conclusion: This study showed that over fifty percent of Toxoplasma infection occurs in twenty-five years of age. Furthermore, it showed that 36.6% of the studied population (pregnant women) was seronegative. Therefore, Toxoplasma infection should be screened in pregnant women in the first trimester of pregnancy in order to perform preventative measure of congenital toxoplasmosis.

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 Introduction: Bovine milk is the first and most common cause of food allergy in early childhood with a prevalence rate of about 2-7/5%. The milk coagulum consists of four proteins α_S1, α_S2, β and к-caseins. Cow's milk caseins play a basic role in persistence of cow’s milk allergy (CMA) in children. Proteolytic system of lactic acid bacteria (LAB) has the ability to hydrolyze antigenic epitopes of milk proteins and, as a result, can reduce allergy to caseins.The aim of this study was to isolate the best lactic acid bacteria strain from cow’s milk samples in order to reduce bovine milk caseins allergenicity. 
 
Materials & Methods: In the present study, after isolation of 30 cocci LAB from 20 Iranian cow’s milk samples, the effect of proteolytic activity of these bacteria on milk caseins was investigated by SDS-PAGE and RP-HPLC techniques. Subsequently, among the 15 strains with protease activity, the binding ability of native and hydrolyzed α_S1-casein to IgE sera from cow’s milk allergic patients was determined by competitive ELISA test.
 
Findings: After accomplishing biochemical tests including gram staining and catalase test, molecular identification of the strains was done by 16s rRNA fragment sequencing. The obtained results suggested that Lactococcus lactis was able to hydrolyze casein fractions in both skim milk and sodium caseinate and could reduce allergenicity of bovine milk α_S1-casein.
 
Discussion & Conclusions: Our conclusion demonstrated that the isolated Lactococcus lactis strain from cow’s milk samples can be used as a main or adjunct starter culture in dairy products to reduce immunor-eactivity of cow’s milk caseins.  

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Introduction: So-called biofilm or biomass is interacting cells or microorganisms that accumulate together as a result of various factors on a surface. Biofilm formation increases resistance to unfavorable conditions and biocides. Of the strategies to deal with biofilms is using different plant compounds and nanoparticles. The aim of this study was to determine the effect of silver nanoparticles, lavender extract, and their combined effects in different concentrations on Klebsiella pneumoniae biofilm.
 
Materials & Methods: The anti-biofilm effect and reduced rate of biofilm formation of Klebsiella pneumoniae in separated and combined treatments of stoechas extract (Lavandula stoechas) and silver-nanoparticles at 24, 48 and 72 hours were measured by colorimetric microtiter method. Phenolic content was also measured by Folin-Ciocalteu method.
 
Findings: Phenolic content was about 113.3
mg/g. In the absence of treatments, Klebsiella was able to form strong biofilms. Three-way-analysis of variance of the main and interacting effects of silver nanoparticles, lavender extract and time on biofilm formation was significant. Silver nanoparticle and lavander extract at concentrations of 125 and 0.0625 ug/mL, respectively, and co-treatments at 62.5 and 0.03125 ug/mL concentrations, respectively, significantely reduced biofilm formation.
 
Discussion & Conclusions: By increasing time, biofilm formation reduced due to effects of treatments. Biofilm formation also reduced by increasing concentration of the treatments. The result of this survey showed that silver-nanoparticles and lavender extract have synergistic effects on reduction of biofilm formation.