In recent years, there has been an increasing interest in usage of portable lightweight and accurate instrument such as refracto meter in dairy industry. This paper attempts to show that each one of mentioned instruments in various cut-points what will be their performance. Randomly, 80 cattle (primiparous and multiparous) selected and lactation number, calving ease score, volume of colostrum at first-milking were recorded and somatic cell count (SCC), total solid (TS), specific gravity, Brix% reading and immunologlobolin G concentration of colostrum sample measured. Thirtytwo percent of colostrum samples in the current study had IgG concentration of lower than 50 g/L. The results showed an acceptable correlation (R2=0.679) between Brix% reading and IgG concentration measured by enzyme linked immunoabsorbant assay (ELISA), also interaction of hydrometer method and digital Brix refracto meter (%) had a strong and positive (R2=0.711) correlation. Performance of digital Brix refracto meter for identifying low quality colostrum elevated at cut-point 24%, so that the sensivity and specificity of instrument in mentioned cut-point were 85.5% and 96%, respectively. The current results confirmed digital Brix refracto meter is accurate and have a good correlation with IgG concentration of colostrum, and diagnostic characteristics test of device could be better if used of fixed colostrum volume for measurement, but in the colostrum samples with high SCC adequacy of this portable on-farm device falls down.

Introduction: Immunoglobulin G is the most abundant immunoglobulin in human blood, comprising approximately 75% of serum antibodies. Human IgG is a glycoprotein and can be an antigen for other mammals. Antibody-sensitized red blood cells (RBCs) and complement components can react with anti-human globulins resulting in their agglutination. This study aimed to prepare an antiserum against human IgG for deploying in Coombs Wright and cross-match for rare blood groups. Methods: After isolation of serum from healthy blood donors, serum proteins were precipitated using ammonium sulfate. Consequently, tangential flow filtration and ion-exchange chromatography were applied to purify IgG. SDS-PAGE and Bradford protein content assay was conducted to evaluate the quality and the concentration of the purified IgG. Rabbits were weekly injected with different amounts of the protein four times. Then, sera were obtained from the immunized mice, and total IgG was purified. Finally, the Coombs Wright test was performed on samples from brucellosis patients to validate purified IgG antibody quality. Results: Electrophoresis and Bradford assay results showed that the purified protein had considerable high purity and quantity. Protein bands of reducing and the non-reducing SDS-PAGE showed high purity of the protein along with a protein yield of 2. 2 mg/L. Coombs Wright tests using the rabbit anti-human serum had a comparable result with available commercial anti-human immunoglobulin. Conclusion: The results indicated that our method for the purification of IgG was suitable for anti-human globulin preparation. This antibody can also be used in clinical diagnostic tests such as Coombs Wright, cross-match, and blood types evaluation with weak Rh or Du antigens.

Background and Objectives: The cytotoxin-associated gene (cag) pathogenicity island is reported to be a major virulence factor of Helicobacter pylori infection. It is previously reported that the cagA-positive strains are more virulent, so it can be postulated that the cagA-positive gastritis will be more severe and the serum immunoglobulin G (IgG) and A (IgA) anti-CagA antibody titer will be higher. The aim of this study was to compare the relationship between IgG and IgA anti-CagA antibody and the cagA gene expression in patients with dyspepsia. Serum samples obtained from 130 dyspeptic patients with positive H. pylori in histological and Geimsa staining were tested for serum IgG and IgA anti-CagA antibody using the enzyme-linked immunosorbent Assay. The expression of the cagA gene was determined using PCR on the biopsy samples, taken via endoscopy. Results: In our material, the sensitivity of IgG anti-CagA antibody in identifying patients with a proven infection with the cagA-positive strains was 97. 67%, and the negative likelihood ratios was 0. 06. There was not significant correlation between serum IgA anti-CagA and the expression of the cagA gene among the dyspeptic patients. Conclusion: The IgG antibody titer was significantly higher in our patients with the cagA-positive H. pylori strain. However, in daily practice, the level of the IgG antibody titer cannot predict whether or not an individual carries a cagA-positive H. pylori strain, because there is a major overlap in the IgG antibody titer between the cagA-positive and cagA-negative patients.

2Background: Brucellosis is one of the most common infectious diseases transmitted from animal to human. Different methods of blood culture, serology, PCR and ELISA are used to diagnose brucellosis. The aim of this study was to compare the diagnostic value of ELISA tests with Brucella serological tests in patients with brucellosis. Methods: In this cross-sectional descriptive study that was conducted from the beginning of April 2018 to the end of March 2019, 231 patients referred to the Infectious Diseases Clinic of Sina Hospital in Hamadan with clinical symptoms and possible diagnosis of brucellosis were included in the study. 5 cc of blood was taken from the patients to prepare serum, at the same time as Wright, Combs Wright and 2ME serology tests, IgG and IgM ELISA tests were also performed using the ELISA kit of Pishtaz Teb Company (Made in Iran), which is designed with the cut-off method. Then the test results were analyzed with SPSS software, version 16 (SPSS Inc., Chicago, IL, USA). Results: 231 patients suspected of brucellosis including 147(63. 64%) men and 84(36. 36%) women with an average age of 44. 60±16. 16 years and a minimum of 10 years and a maximum of 80 years were examined. IgG and IgM results were positive with brucellosis in 80. 1% and 30. 30%, respectively. The results of IgG and IgM were positive in 1/80 and 30. 30%, respectively, and they were diagnosed with brucellosis. In comparison with 2ME, Wright and Coombs-Wright serology tests, the sensitivity of IgG was between 83. 80% and 94. 28% and its specificity was between 20 and 33. 34%, the sensitivity of IgM was also between 34. 78 and 40. 0% and its specificity was between 78. 67% and 89. 47% at different cut points. Conclusion: Compared to diagnostic serological tests for brucellosis, IgG is more sensitive and IgM is more specific. If serological tests are not available, ELISA can be used to diagnose brucellosis. But because of their lower diagnostic value, they cannot be replaced

Objective: There are some controversial studies on effects of anti-epileptic drugs (AEDs) on serum IgG subclasses; however, the role of these medications is still unclear. The aim of this study was evaluation the effects of anti-epileptic drugs on serum concentration of IgG and its subclasses.Methods: Serum IgG and IgG subclasses of 61 newly diagnosed epileptic patients were measured at the beginning of monotherapy with carbamazepine, sodium valproate, and phenobarbital, and 6 months later. Measurement of IgG and its subclasses was performed using nephlometry and ELISA techniques, respectively.Findings: Reduction of at least one IgG subclass was found in 6 patients 6 months after treatment with AEDs. Among 27 patients receiving carbamazepine, decrease in at least one serum IgG subclass level was found in 5 patients. Among 20 patients using sodium valproate, only one patient showed decrease in IgG2 subclass. None of the 14 patients using phenobarbital revealed significant decrease in IgG subclasses. No infection was seen in the patients with reduction of subclasses.Conclusion: Although in our study, children with selective IgG subclass deficiency were asymptomatic, assessment of serum immunoglobulin levels could be recommended at starting the administration of AEDs and in serial intervals afterward in epileptic patients.

Background: Concerns on the safety of polio vaccine in some parts of northern Nigeria that led to the suspension of the immunization efforts in those parts of the country, informed our design of this prospective study.Objective: To determine polio-specific Immunoglobulin G antibodies among children (seven months - seven years) in Jos.Methods: Within the months of March and April 2007, One hundred and eighty two blood samples were collected from children in the Emergency Peadiatric Unit of the Jos University Teaching Hospital and tested for the presence of polio-specific IgG antibodies using Poliomyelitis IgG ELISA Test Kit produced and described by DEMEDITEC Diagnostic GmbH Germany.Results: One hundred and seventy eight percent (97.8%) of the tested children had detectable antibodies against poliovirus. The study population had appreciable levels of protection against poliovirus. There was no significant association between the detection of the IgG in children in relation to gender, age, religion, and number of doses. Only educational status of fathers had statistically significant relationship with the detection of the antibodies.Conclusion: This study demonstrated that progress has been made towards the eradication of poliomyelitis in Nigeria. To further strengthen the gains made and weaken the barriers to immunization, there is an increasing need for more funding to increase awareness and intensify the final efforts targeted at ‘kicking polio’ out of Nigeria.