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Background:Accumulative research is in progress to clarify clinical aspects of GBV-C. The possibility of interaction between HCV and GBV-C as well as its consequence on development of liver diseases is the most important clinical aspect which encourages researchers to develop a rapid and cost effective technique for simultaneous detection of both viruses. Methods: In this study, a SYBR Green real time multiplex RT-PCR technique as a new economical and sensitive method was designed and validated for simultaneous detection of HCV/GBV-C in HCV positive plasma samples. SYBR green real time RT-PCR technique optimization was performed separately for each virus. Multiplex PCR was established next. Standard sera with known concentrations of HCV RNA and dual HCV/GBV-C positive control samples along with negative control samples were used to validate the assay. Results and Conclusions:  Fifty six non cirrhotic HCV positive plasma samples [29 of genotype 3a and 27 of genotype 1a] were collected from patients before receiving treatment. 20.6% of genotype 3a and 18.7% of genotype 1a showed HCV/GBV-C co-infection. As a result, 19.6% of 56 samples had HCV/GBV-C co-infection that was compatible with other results from all over the world. SYBR Green real time multiplex RT-PCR technique can be used to detect HCV/GBV-C co-infection in plasma samples. Furthermore, with application of this method more time and cost could be saved in clinical-research settings.

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Objectives: Salmonella typhimurium is important food-borne pathogen responsible for gastroenteritis. In this work a polymerase chain reaction based enzyme linked immunosorbent assay (PCR-ELISA) was developed to identify Salmonella typhimurium. Materials and Methods: The rfb gene which is responsible for biosynthesis of the Salmonella O-antigenic lipopolysaccharide was selected as the target sequence. The selected primers amplified fragment size of 882bp of S. typhimurium. Food samples contaminated with Salmonella typhimurium as well as clinical and standard samples were used in this investigation. The PCR products randomly labeled with Dig-11-dUTP were transformed to a plate coated with streptoavidin and tested with anti digoxigenin. An internal biotin-labeled probe was used to confirm the amplified PCR product. Results: The specificity of the assay toward S.typhimurium samples was confirmed by testing 20 Salmonella and 6 non Salmonella strains. ELISA increased the sensitivity of the conventional PCR method by approximately 1000 fold. Conclusion: The method presented here is a rapid and specific alternative for the traditional time consuming culture methods for the detection of S. typhimurium in food and clinical samples. Due to its high specificity and sensitivity, our method finds its place as an alternative to PCR in large scale screenings, for detection of S. typhimurium.

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Rapid test methods are laboratory instruments that can be used in the point of care and for suspicious cases. In an ideal rapid detection method, the steps for preparing a sample to obtain an analytical result should be as short as possible, and unskilled operators should be able to execute it and understand the result. To accomplish such a process, it is better to perform all the steps including sample preparation, detection procedure and acquisition of an intelligible signal in one device. These assay systems can include microfluidic chips, paper-based sensors, or even single-tube reactions. Corona Pandemic offers many products for the rapid detection of the Covid 19 virus, which diffrent products were commercially developed. Due to the sensitivity of the diagnosis at different stages of the disease, only a small number of technologies could be applied in practice. In this review article, these products are categorized and reviewed based on technological properties. Also, these technologies have been compared in terms of important components such as sensitivity, accuracy, cost and speed of the process in the diagnosis and management and control of COVID-19 pandemic. Also the application of each technology is explained. Finally, the best technology that can play a major role is introduced.

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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.