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  Background : Type 1 diabetes mellitus (T1DM) is an autoimmune disease characterized by selective destruction of pancreatic beta cells.   Methods: The study included 80 children, 20 of them have T1DM, 40 children were selected from first degree relatives to the same child and 20 healthy children serve as control. Body mass index (BMI) was calculated, random blood glucose and glycosylated hemoglobin A1c (GHbA1c) were measured. The following biochemical markers were measured in sera of all subjects by ELISA kits: Human insulin ,C-peptide, human islet cell antibody (ICA), insulin auto antibodies (IAA) and antiglutamic acid decarboxylase (anti-GAD) antibodies. Results : This study showed that diabetic children had high level of ICA (65%), IAA (55%), anti-GAD antibodies (50%) and decrease in C-peptide (60%). Whereas the relatives showed high level of anti-GAD antibodies (30%), IAA(25%), ICA(2.5) and decrease in C-peptide (30%). Anti-GAD antibodies were significantly higher among the relatives of the diabetics compared to the healthy controls. Conclusions : The strongest predictors of diabetes were C- peptide and islets cell antibodies, which had odd ratio 4.7 and 3.1, respectively. Autoantibodies could distinguish T1DM patients from healthy control subjects and they may also identify individuals at high risk during progression from pre-diabetes to overt disease.

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Backgrounds: A novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has now spread to all countries of the world, including Iran. Although anti-SARS-CoV-2 antibodies may be identified in patients using immunological methods with sufficient sensitivity and specificity, the conclusive diagnosis of the disease is made using the molecular RT-PCR method. A population-based seroepidemiological survey was conducted to quantify the proportion of the exposed population with SARS-CoV-2 antibodies and evaluate whether the antibodies are a marker of total or partial immunity compared to the population that remains susceptible to the virus.
Material & Methods: This cross-sectional study was conducted to investigate the seroprevalence of COVID-19 in Valiasr, Sajad, and Ghaem hospitals in Tehran, the capital of Iran, from April to the end of October 2020. Clotted and heparinized blood specimens (2mL) were collected from the patients. The serum and plasma were separated and stored at −80 °C until use. Anti-SARS-CoV-2 IgG and IgM antibodies were examined in the serum samples of 1375 in-patients admitted to the hospitals using ELISA kits. The obtained data were analyzed using SPSS software Ver.22.0 by employing statistical tests such as Chi-square and Fisher’s exact tests. A p-value <.05 was considered as significant.
Findings: In total, 1375 participants were enrolled in this study, and SARS‐CoV‐2 antibodies were detected in 291 patients using IgM‐IgG antibody assay. Among the seropositive patients studied, 187 were male (64.3%), and 104 were female (35.7%) (p<.05). The mean age of the patients was 49±8.4 years; the majority of whom (27%) were in the age group of 31-40 years. Also, the lowest frequency of infected cases was related to the age group of 1-10 years (p <.05). The seroprevalence of SARS‐CoV‐2 IgM or IgG antibodies was determined to be 21.2%. Diabetes mellitus was the most common underlying disease among SARS‐CoV‐2 patients [p=.05; Odd Ratio=1.61(0.90-2.91)].
Conclusion: The use of conventional serological assays, such as the enzyme-linked immunoassay (ELISA), for detecting specific IgM and IgG antibodies in SARS‐CoV‐2 patients has a high-throughput advantage while minimizing false-negative results obtained using the RT-PCR method. In this study, the seroprevalence of SARS-CoV-2 antibodies was determined to be 21%. Control of diabetes, among other influential factors, plays an important role in the management and control of COVID-19.

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A survey was carried out in five provinces of Iran (Kerman, Sistan and Baluchestan, Hormozgan, Khorasan and Yazd) for the presence of Alfalfa mosaic virus (AMV) sero-types in alfalfa during 2002 to 2003. The number of samples collected was 250, represent-ing the diversity and geographical distribution of AMV in these areas. Diagnosis was car-ried out using polyclonal (PAbs) and monoclonal (MAbs) antibodies. A total of 110 symp-tomatic leaf samples gave a positive reaction in ELISA with polyclonal antibodies. Twelve out of 20 MAbs reacted with all samples tested and were considered as non-differentiating MAbs. Only the MAbs-12, 13, 15, 21, 22 and 24 gave a clear differential reaction and were used for identifying AMV serotypes. Two MAbs (1 and 2) did not react with AMV posi-tive samples. Serological relatedness among AMV samples was studied by indicating the existence of six serotypes of AMV strains in the surveyed areas.

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Background and Aim: Toxins produced by Clostridium botulinum are among the deadliest compounds known that cause botulism. Currently, the detection of BoNTs in food using bioassays on laboratory mice is a very sensitive method with a detection range of 7 to 20 pg.mL^-1. However, bioassay for mice is time consuming. This method is fast, highly specific, and sensitive to experiments on mice. The aim of this study was to use the modified Sandwich ELISA method to detect BoNT/B toxin.

Materials and Methods: Recombinant 370 amino acid protein was expressed from the carboxyl terminus of the binding moiety of BoNT / B toxin with a molecular weight of 45 kDa as antigen and purified by Ni-NTA affinity chromatography. IgG antibodies were isolated from mouse and rabbit sera byG protein affinity chromatography. The sensitivity and specificity of the method designed to detect recombinant BoNT/B-HcC antigen and botulinum toxin type B were evaluated.

Results: Purified rat and rabbit antibody concentrations were 3 and 4.5 mg / ml serum, respectively. The minimum concentrations of detectable protein were determined by indirect ELISA with purified mouse and rabbit antibodies at 475 and 118 pg. By optimizing the sandwich ELISA method, at least 30 ng of recombinant BoNT/B-HcC antigen and146 pg of highly specific BoNT/B were detected.

Conclusion: sandwich ELISA method can be used for accurate and sensitive identification of Clostridium botulinum toxin type B. It is necessary to evaluate the effectiveness of this method in the future to detect botulinum toxin in environmental and food samples.
 

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Objective: Cholera is an endemic disease in Iran. Early detection, especially in times of disease outbreaks, is of vital importance. The antibody against the lipopolysaccharide (LPS) is an important method for bacterial detection. This study intends to extract and purify the LPS of Vibrio cholerae and evaluate the cholera antibody for detection purposes. Methods: Vibrio cholerae was cultured in tryptone extract medium. LPS was extracted by the hot phenol water method, purified, and dialyzed. We measured the LPS protein and sugar content, purity, and biological activity. Antibodies were produced by injection of the killed bacteria with Freund's complete adjuvant into rabbits and then the LPS was injected three times with Freund's incomplete adjuvant. After the last booster, blood samples were taken. We used ELISA to determine the antibody titers against the Inaba and Ogawa serotypes, the LPS of these serotypes, and several other similar bacteria. Results: The amount of protein in the purified LPS was approximately zero and sugar was 0.5 mg/ml. The LPS had a titer activity of 1024, and consisted of three bands (5.2, 4, and 5.14 KD). Antibodies produced by the rabbits identified the bacterial Inaba and Ogawa serotypes, and the purified LPS. Ogawa and Inaba serotypes cross-react with each other but not with other species of Vibrio and other bacteria. The LPS antibody titer against the Ogawa serotype was 1:32000, whereas for Inaba it was 1:16000. Conclusion: Due to the low cost of production, high sensitivity, and importance of cholera diagnosis in Iran, the antiserum produced in this study can be used as a tool for early screening of cholera and discrimination of O1 strains from non-O1 strains in immunologic tests.

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Coronavirus disease 2019 (COVID-19) is a virally-induced pneumonia caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This is the third disease-causing coronavirus after severe acute respiratory syndrome coronavirus (SARS-CoV) and the middle east respiratory syndrome coronavirus (MERS-CoV) which has been known in the human population in the 21^st century. To this date (20^th of Mehr, 1399), more than thirty-four million people have been infected by this virus and more than a million have lost their lives because of it which further signifies the importance of COVID-19 prevention and treatment. In this review article, we first take a look at the history of the famous coronaviruses and then introduce the genetic and pathophysiology of SARS-CoV-2 in a detailed manner. After discussing the related clinical manifestations, we shed a light on the treatments that have been assessed to this date. In the end, we will briefly discuss the vaccines that are currency being developed and highlight their success rate, so far. It is delightful to assert that out own research team is currently developing an oral and/or respiratory vaccine against SARS-CoV-2 which is composed of spike-surface decorated chitosan nanoparticles.