Showing 6 results for Rt-Pcr
Shahab Falahi, Mehrdad Ravashad, Azra Kenarkoohi,
Volume 14, Issue 4 (9-2011)
Abstract
Background: Polymerase chain reaction is the most common technique in the field of molecular biology that use for amplification of a specific nucleic acid sequence. Degenerate primers have ability to amplify related but distinct sequences. The aim of current study was to use, two sets of degenerate primers in combination with Hemi Nested PCR for detection V3-Loop sequence of envelope gene from wide spectrum of Human Immunodeficiency Virus (HIV) subtypes.
Material and Methods: In this experimental study we designed and optimized, a degenerate primer pair in combination with Hemi Nested PCR, to detect HIV-1 V3 loop from Envelop gene that has wide variations among genotypes. The developed assay was used to check, 40 HIV infected, 10 negative controls as well as 5 samples from each HCV, HBV, HGV, and TTV were analyzed using developed method.
Results: after optimization, 35 out of 40 positive controls were positive using our test. None of the negative human and viral control samples showed specific band. Also, in positive samples, non-specific bands were not detected.
Conclusion: In this study moreover than standard PCR, we used two degenerate primers that could detect specific region of genome. In fact, first round of PCR product act as a template for second round inner primers and can produce smaller sequence with high sensitivity due to degeneracy. Based on the current investigation, the developed assay had advantages including product confirmation and hence more sensitivity.
Mahdi Paryan, Mahdieh Mondanizadeh, Samira Mohammadi-Yeganeh , Behzad Khansarinejad,
Volume 14, Issue 5 (11-2011)
Abstract
Background: HIV-1 and HCV are two of the most important blood-borne infectious agents. Hence, reliable, precise, and sensitive detection of these viruses in infected patients and donated blood units is highly important. Noticing the limitations of serological assays in detection of these infectious agents, this study was to use fast and sensitive molecular assays like real-time PCR.
Materials and Methods: In this trial, a home-brewed SYBR green-based multiplex real time PCR, on the basis of melting curve analysis, was developed for the single or simultaneous detection of HCV and HIV-1 infections in plasma samples. Data were analyzed using SPSS software version 16.
Results: The results obtained from different reactions on several clinical samples showed that the analytical sensitivities of the developed assay for HIV-1 and HCV were 200 and 100 copies/ml, respectively. It was also shown that the primers designed for each virus had no interaction with each other and other interfering agents.
Conclusion: Noticing the good level of sensitivity and specificity, easy handling, relatively low cost, and rapid analysis of samples, this method can be a useful and rapid approach for simple and effective detection of HCV and HIV-1 in plasma samples.
Mohammad Reza Arabestani, Mojtaba Rajabpour, Rasoul Yousefi Mashouf, Mohammad Yusef Alikhani, Seyed Masoud Mousavi,
Volume 17, Issue 11 (2-2015)
Abstract
Background: Pseudomonas aeruginosa is one of the most common nosocomial pathogens with high mortality rates. OprD is the major resistance mechanism to carbapeneme antibiotics. The aim of this study was to determine the expression of the genes encoding these efflux pumps using qRT-PCR.
Materials and Methods: This study examined 100 strains of Pseudomonas aeruginosa isolated from patients admitted to various hospitals in the Hamedan. Conventional phenotypic tests were used for identifying the 100 collected samples, then 31 samples were selected based on type of collected specimen and antibiotic susceptibility test i.e. antibiotic disk diffusion method performed for aminoglycoside, quinolone and carbapenem antibiotics. Furthermore, MIC method was performed for imipenem. Finally, RNA was extracted and converted to cDNA for determining the efflux pump genes expression using qRT-PCR.
Results: Among 8 selected antibiotics, the greatest resistance was for levofloxacin (61.2%, n=19) and the lowest one for imipenem (9.6%, n=3). The results of MIC were to imipenem 12 samples (38.7%) resistant, 13 samples (41.93%) intermediate, and 6 samples (19.35%) sensitive. The OprD gene was present in all strains but different expression has been observed. The strains with over expression of OprD gene showed high sensitivity towards carbapenems family antibiotics especially imipenem.
Conclusion: Identifying of bacterial resistance mechanisms is very complicated and extensive due to different mechanisms involved for similar antibiotics. OprD is main cause of attachment to the carbapenems family antibiotics. The more expression of OprD shows the more antibiotic sensitivity.
Sara Karimi Moghadam, Roohollah Dorostkar, Saeed Hesami Takallou,
Volume 20, Issue 11 (2-2018)
Abstract
Abstract
Background: Breast cancer is the most common cancer in Iran and breast cancer is the fifth leading cause of death among women. Diagnosis of breast cancer in early stages could increase the lifetime of more than 90% of patients. Human endogenous retroviruses are as heterochromatic parts of the genome, lack any expression. But in several categories of human cancers, including breast cancer, there is a significant increase in the level of HERV-Kenv mRNA.
Materials and Methods: In this case-control study, blood samples were collected from 40 breast cancer patients admitted in Baqiyatallah Hospital and 20 healthy individuals to study the increased expression of HERV-Kenv mRNA using specific primers and were tested by RT-PCR.
Results: Investigations on the patient and control groups showed that increased expression of mRNA was positive in 60% of patients with breast cancer and negative in all healthy subjects.
Conclusion: The results of this study showed that expression of mRNA HERV Kenv in breast cancer was increased. Since enhancement of mRNA HERV-Kenv in the blood of breast cancer patients occurs in of disease, these retroelements could be used as a diagnostic biomarker
Mina Ghasemi, Zeinab Khazaei Koohpar, Mojtaba Falahati,
Volume 21, Issue 3 (6-2018)
Abstract
Background and Aim: Prolonged ischemia in organs with high metabolic rates such as brain and heart is associated with deleterious effects. Therefore, nutritive distribution through angiogenesis after ischemia is necessary for repairing damaged region of tissue. In this study, the effects of iron oxide nanoparticles and magnetic field on angiogenesis after ischemia reperfusion (IR) in rat model have been investigated.
Materials and Methods: In this experimental study, fifty male rats aged between 6 -7 weeks at the 220-250gr weight were purchased from Tehran University. Animals were categorized in 5 groups including sham (ischemia reperfusion model), control, iron oxide nanoparticles-treated, magnetic field-exposed, and combination therapy with iron oxide nanoparticles and magnetic field-exposed groups. Angiogenesis was evaluated in hippocampus of 5 groups after 4 days by H&E staining method. The expression of Vegfa gene was studied in 5 groups by Q-RT- PCR.
Findings: Iron oxide nanoparticles as well as the magnetic field induced angiogenesis during 4 days in animals after IR (p<0.05), but their combination therapy did not show any significant difference compared to sham group during 4 days. Upregulation of Vegfa gene was observed in iron oxide nanoparticles treated group and the magnetic field exposed group significantly (p<0.05) relative to ischemia reperfusion (IR) model. But overexpression of Vegfa gene in combination therapy group was not significant relative to ischemia reperfusion (IR) group.
Conclusion: It seems that iron oxide nanoparticles and magnetic field can separately be two effective methods for angiogenesis after ischemia reperfusion (IR).
Mehrdad Nasrollahzadeh Sabet, Mohammad Foad Heidari, Mohammad Khanalipour, Saadat Allah Ghaffari, Milad Jafari Ashiani, Sajjad Biglari, Emran Esmaeilzadeh,
Volume 23, Issue 5 (11-2020)
Abstract
Background and Aim: Since late 2019, with the emergence of a new type of coronavirus that causes a new respiratory disease called COVID-19, there have been many concerns about the spread of this disease and how to deal with it. Due to the ability of the virus to be transmitted rapidly, diagnosing the infected individuals in the early stages for isolating them is critical. This study aims to evaluate the reliability of Computed Tomography (CT) scan in diagnosing COVID-19.
Methods & Materials: Participants were 212 patients admitted to hospital with confirmed diagnosis of COVID-19. Demographic information, medical history, symptoms, and the chest CT scan results were collected and analyzed. Finally, the power of CT scans in the diagnosis of this disease was compared with the Real-Time Polymerase Chain Reaction (RT-PCR) molecular test.
Ethical Considerations: This study received ethical approval from the ethics committee of AJA University of Medical Sciences (Code: IR.AJAUMS.REC.1399.091).
Results: The sensitivity of CT scan in the diagnosis of COVID-19 was relatively high, but its false-positive results were also high.
Conclusion: CT scan is a relatively sensitive method for diagnosing COVID-19, but caution should be made due to its high false-positive results which can lead to increased financial burden on the health system.
