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BACKGROUND: To improve urinary tract infection detection, we evaluated the specificity and sensitivity of Loop-mediated isothermal Amplification Method (LAMP) for detection of the Eschericia coli (E. coli) in urine samples, for the first time. METHODS: Primers were designed to target the malB gene of Escherichia coli. LAMP assay was performed on urine specimens collected from patients with urinary tract infection symptoms. RESULTS: As expected, LAMP was more specific and sensitive than direct microscopic tests. LAMP assay showed the best detection limit of DNA copies with 1.02 copies. CONCLUSION: LAMP method offers several advantages in terms of sensitivity, rapidness and simplicity for detection of E. coli infection in urine samples. The LAMP method would be highly suitable for the early detection of the UTIs and also comfort quick diagnosis of UTI in clinical laboratories with limited equipment.
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BACKGROUND: This study investigated the effects of Riboflavin (RB) combined with different doses of UV on Platelet Concentrate (PC) which was infected by three models of virus. Platelet quality after treatment was also assessed. METHODS: Three models of virus used in this study were Vesicular Stomatitis Virus (VSV), Herpes Simplex Virus (HSV), and Polio virus, which were added to PC. After photochemical treatment with RB and UV light, residual viral infectivity was titrated using 50% Tissue Culture Infective Dose (TCID50)/ml. This treatment was done with concentration of 50 µM of RB and different doses of UV light (0.24, 0.48, 0.97, 1.29 J/cm (2)). Platelet quality was assessed by measuring pH, Lactate Dehydrogenase (LDH), MTT assay and cell count after treatments and during 4 days of storage against control groups. RESULTS: Concentration of 50 µM RB with combination of 1.29 J/cm (2) dose of UV resulted in the highest titer reduction of VSV (4 log 10) and HSV (4.26 log10) and lowest titer reduction of Polio virus (2.6 log10). No significant difference was observed between different doses in comparison with control groups. In all treatment groups, the storage stability of platelets in PC was in the acceptable range in comparison with control group. CONCLUSION: This study indicated that RB/UV treatment was a promising pathogen reduction technique in PC and had limited effects on platelet quality. However, further optimization of this method is necessary to deal with blood-borne viruses like non-enveloped viruses.
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BACKGROUND: The HBV-X (HBX) protein is believed to contribute to the development of HCC. However, the molecular mechanisms involved in HBX- mediated hepatocarcinogenesis remain obscure. In this study, the effect of hepatitis B virus X gene and its protein product HBxAg on expression of p53 gene in Hep G2 cell line was investigated. METHODS: Viral DNA extracted from HBV-positive serum and HBX gene region was amplified using polymerase chain reaction (PCR). Then, PCR product was cloned into the pcDNA3 vector. After confirmation of cloning, the recombinant plasmid pcDNA3-X was transfected into HepG2 cell line using lipid-mediated DNA-transfection procedure. SDS-PAGE and western blotting methods were used to identify expression of HBX protein. Relative quantification was used to analyze the p53gene expression using the 2-(ΔΔ Ct) method. RESULTS: Recombinant plasmid pcDNA3-HBX was confirmed by restriction endonucleases digestion and colony-PCR. The results of SDS-PAGE and western blot assays showed that HBX gene could be expressed in Hep G2 cell line. There was no significant difference between the expression levels of p53 compared with GAPDH gene as housekeeping gene (p < 0.05). CONCLUSION: There was no significant difference in the protein levels between the transfected cells with X gene containing HBX130 and HBX131 double mu-tations and p53 gene. It is necessary to do more studies on Hepatitis B virus to understand the role of HBX on the development of liver cancer and its function on p53 tumor suppressor protein.
ABSTRACT
BACKGROUND: Hepatitis delta virus is a unique human pathogen responsible for some 20 million infections globally. This virus is dependent on hepatitis B virus for transmission and propagation. Currently, at least three genotypes of hepatitis delta virus with different geographic distribution and clinical manifestations are described. METHODS: In this study, hepatitis delta virus RNA of 35 patients' sera were analyzed by RT- semi-nested polymerase chain reaction. Based on genomic differences of hepatitis delta antigen coding region of hepatitis delta virus RNA among hepatitis delta virus RNA-positive sera, the polymerase chain reaction products were digested with restriction enzymes and studied by restriction fragment length polymorphism. RESULTS: Out of 35 samples, 13 (38.46%) were positive for hepatitis delta virus RNA by RT- semi-nested polymerase chain reaction. All polymorphisms were shown to be genotype I. Out of 13 hepatitis delta virus RNA-positive (13/35), eight were HBeAg negative. CONCLUSION: Our data indicated that hepatitis delta virus isolates in Tehran are exclusively genotype I.
