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Showing 7 results for Pcr
A Study of helicobacter pylori presence in patients with gastrointestinal disorder
Sh. Jafari , N.  ebrahimi-E- Daryani , S. Zeinali, M.  motalleb Nejad ,
Volume 14, Issue 2 (8-2001)
Abstract
Helicobacter pylori infection causes gastric and duodenal ulcer. However recurrence of infection after eradication would suggest the existence of other reinfecting sources in the gastrointestinal tract (Gl). The aim of this study was to assess the existence ofhelicobacter pylori in dental plaques of patients harboring Helicobacter pylori in their GI tract. Antral biopsies were taken from 40 patients with Gl problems and cultured. Samples were also taken from dental plaques of patients with positive Helicobacter pylori culture under microaerophilic conditions and evaluated by polymerase chain reaction (PCR) reamplification. The mean age of patients was 40 years 24 (60%) male and 16 (40%) female. The results obtained from dental plaque cultures, which analysed by PCR were all negative, however 7 (17.5%) cases were found positive by PCR reamplification. The results showed that Helicobacter pylori could exist in dental plaque and PCR reamplification could be used for its detection as a more sensitive technique. More research should be conducted to examine any relation between the existence of Helicobacter pylori in dental plaques and recurrent GI disorders.
Investigation of p53 codon72 polymorphism in oral squamous cell carcinoma (SCC) specimens and normal population by PCR
P. Deyhimi, M. Nikbakht Dastjerdi, F. Morsali, Sh. Kazemi,
Volume 21, Issue 1 (10-2008)
Abstract

Background and Aim: A single nucleotide polymorphism at codon 72 of the p53 gene alters the p53 protein structure and affects its activity. This polymorphism depends on geographic regions and race. Also its association with some cancers has been reported. The aim of this study was to investigate this polymorphism in well differentiated oral SCC and normal population in the city of Isfahan.

Materials and Methods: In this case-control study, 20 paraffin blocks of non metastatic and well differentiated oral SCC were selected from the archive of oral pathology department of dental school between 2001 and 2005. 20 whole blood samples from normal people were considered as control group. After DNA extraction, p53 codon 72 polymorphism was determined by polymerase chain reaction (PCR) technique using specific primers of Arg and Pro and agarose gel electrophoresis. Data were analyzed by Fisher's exact test with p<0.05 as the level of significance.

Results: The prevalence of Arg/Arg , Arg/Pro and Pro/Pro genotypes in case group were 45%,45% and 10% respectively compared to 45%,50% and 5% in controls. There was no statistical significant difference in p53 codon 72 genotypes distribution between case and control groups.

Conclusion: Based on the results of this study, p53 polymorphism could not be considered as a genetic predisposing factor for oral SCC development in Isfahan.


Prevalence of periodontopathogenic bacteria in patients suffering from periodontitis using culture and PCR methods
Amir Aliramezani, Mohammad Hosein Salari, Mohammad Reza Pourmand, Zeinab Kadkhoda, Abbas Foroushani, Farzaneh Aminharati, Sedigheh Ghourchian, Zahra Pakbaz, Saeed Eshraghi,
Volume 25, Issue 3 (7-2012)
Abstract

Background and Aims: Periodontitis is one of the most common oral diseases with the various incidence rates in different populations. A number of bacteria are considered as the major etiologic agents of periodontitis. The aim of the present study was to determine the prevalence of periodontopathogen bacteria in patients using both PCR and culture techniques.
Materials and Methods: In this study, one-hundred patients (including 62 females and 38 males with an average age of 49±11.5 years) with adult periodontitis referred to periodontics department of School of Dentistry/Tehran University of Medical Sciences were investigated. The samples were taken and sent immediately to the laboratory for culture and molecular evaluation. The PCR was performed using specific primers and the statistical analysis of data was performed using SPSS statistic software and McNemar test.
Results: The results demonstrated that the total detection rate in culture method was 64%. The rate of Aggregatibacter actinomycetemcomitans (Aa) was 28% which was significantly higher than that of Porphyromonas gingivalis (Pg) (6%) and Prevotella intermedia (Pi) (3%). 27% of cases showed mixed bacterial growth. 65% of patients were positive using molecular method. The rate of Aa (30%) was significantly higher than that of Pg (7%) and Pi (5%). The mixed PCR positive rate containing of Aa, Pg and Pi was (23%).
Conclusion: In this study, it was found that most of the bacteria isolated using culture and molecular methods were Aa, Pg and Pi, respectively. Although the detection frequencies of both techniques were similar, the specificity, sensitivity and bacterial detection speed of the PCR technique is obviously higher. Therefore, the use of molecular techniques is strongly recommended. However, both techniques seem to be suitable for microbiological diagnostics.


Apoptosis of gingival connective tissue cells in diabetic individuals with chronic periodontitis
Farin Kiani Yazdy, Masoud Golshah, Mahboobeh Razmkhah, Abbas Ghadery,
Volume 26, Issue 2 (5-2013)
Abstract

Background and Aims: Apoptosis or programmed cell death plays an important role in the pathogenesis of many diseases. Previous studies suggest that apoptosis is involved in the pathogenesis of periodontal disease, on the other hand it is also suggested that diabetes mellitus enhances apoptosis of connective tissue cells. Thus, we measured expression of proteins which are relevant to apoptosis in the gingival tissue of diabetic patients with chronic periodontitis in comparison to non diabetic individuals.

Materials and Methods: 25 patients with diabetes and chronic periodontitis and 16 non diabetic controls were included in this study. 4 weeks after scaling and root planning and oral hygiene instructions, periodontal surgery was done and gingival tissues obtained during surgery, were sent to lab to investigate expression of Fas, P53, Bcl-2 and Survivin using real-time PCR technique. Data were analyzed using Mann-Whitney and Chi-squared.

Results: Pro-apoptotic proteins (Fas, P53) were significantly (P<0.05) higher in gingival tissues of diabetics (9.5×10-6, 2.4×10-6, respectively) in comparison to non diabetics (9.4×10-7, 5.6×10-7), whereas the difference in expression of anti-apoptotic proteins (Bcl-2, Survivin) between 2 groups was not significant (9.7×10-8, 3.5×10-7 in comparison to 1.4×10-7, 3.1×10-7, respectively)( P =0.91, P =0.29 respectively).

Conclusion: Apoptosis was increased in gingival connective tissue of diabetic patients with chronic periodontitis in comparison to non diabetic ones. Therefore , intervention in expression or function of pro-apoptotic proteins (Fas, P53) could be a new goal in the treatment of periodontal disease of diabetic patients.


Molecular study of Candida albicans isolated from periodontal infections and effect of Sargasum alga extract on biofilm als gene expression using Real-Time-PCR
Pooneh Mahmoudi, Kiumarss Amini, Parviz Amini,
Volume 32, Issue 1 (7-2019)
Abstract
Background and Aims: Candida is an opportunistic pathogen that causes illness in people with a defective or weakened condition. Infectious diseases (periodontal diseases) are inflammatory and malignant inflammation of the dental-gum complex, in which the growth of biofilms caused by Candida glabrata, Parapseilosis and Tropikalis is less than Candida albicans. Brown algae Sargasum is more compatible with human medicines due to having a natural origin than chemical drugs and has less side effects. The aim of the present study was to investigate the molecular characteristics of Candida species isolated from periodontal infections and the effect of Sargassum glaucescens extract on biofilm gene expression using Real-Time-PCR.
Materials and Methods: Oral samples of periodontal infection were collected from the referred patients. To isolate the candidate species, the specimens were cultured on a Sabouraud dextrose agar containing chloramphenicol (SDAc). The extracted DNA was extracted from colonies grown from Kit and Glass pearl. Grown chickens were identified by specific primers by PCR-RFLP method. In order to detect the expression of als genes in Candida isolates, RNA extraction was performed using Phenol-Chloroform and Pearl glass, and the CLSI-M27-A2 method was used to evaluate the effect of Sargasum glaucescens extract of algae.
Results: The results showed that the expression of als gene in periodontal infection is higher than other genes. Another role is als in the formation of Candida albicans biofilm. The minimum inhibitory concentration of fungal growth was 256 μg/ml by algae extract. Sargasum glaucescens reduced the expression of als gene expression by about 62% in the sample.
Conclusion: Sargasum glaucescens algae possesses specific pharmacological properties and antimicrobial and antimicrobial effects. The results of the study using Real Time PCR showed that expression of als gene in isolated studied with Sargasum algae extract was lower than untreated isolates. Thus, this indicated the positive role of treatment by sargasum glaucescens extract in reducing the expression of biofilm gene in isolates.

Effect of methanolic extract of Zingiber officinale on expression of virulence genes of streptococcus mutans utilizing Real Time PCR
Seyedreza Khosravani, Leila Azimi, Saeed Moghadamzarandi, Narges Panahandeh,
Volume 38, Issue 0 (4-2025)
Abstract
Background and Aims: To prevent dental caries, investigations have focused on finding new antibacterial and anti-biofilm agents without the drawbacks of the currently used synthetic agents. This study aimed to assess the effect of methanolic extract of Zingiber officinale (Z. officinale) on expression of virulence genes of Streptococcus mutans (S. mutans) using real-time polymerase chain reaction (PCR).
Materials and Methods: In this in vitro study, which was conducted in the year 1402, at the Microbiology Department of the Faculty of Medicine and the Faculty of Dentistry at Shahid Beheshti University of Medical Sciences, the methanolic extract of Z. officinale was obtained by the maceration technique. 10 clinical isolates of S. mutans were obtained from the patients with dental infection. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract against S. mutans were determined by the microtiter plate technique. The effect of extract on the expression of relA, comDE, brpA, gtfC, and spaP virulence genes by the clinical isolates was evaluated by the real-time polymerase chain reaction (PCR) technique. Data were analyzed by the Wilcoxon and Mann-Whitney tests (alpha=0.05).
Results: The mean MIC and MBC of the methanolic extract of Z. officinale against S. mutans were 32±11.8 and 64±26.12 mg/mL, respectively. The extract caused down-regulation of relA, comDE, brpA, and gtfC by 50%, 40%, 70%, and 70%, respectively. It also caused 4 times reduction in expression of spaP gene.
Conclusion: The methanolic extract of Z. officinale caused significant down-regulation of gtfC, brpA, relA, comDE, and spaP genes, indicating its optimal efficacy to control the virulence of S. mutans.

Detection of SARS-CoV-2 RNA in aerosols of clinical and non-clinical areas of a dental clinic during the post-pandemic period
Mogtaba Bayani, Hadiseh Mohammadi, Behzad Khonsarinejad, Dr. Seyed Hamed Mirhoseini,
Volume 39, Issue 0 (3-2026)
Abstract
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Background and Aims: The SARS-CoV-2 virus, capable of airborne transmission through aerosols, poses a significant challenge in clinical settings such as dental clinics. The use of high-speed instruments, including handpieces and ultrasonic scalers, generates considerable aerosols that, if contaminated, may facilitate infection transmission. This study aimed to detect the presence of the  SARS-CoV-2 virus in the clinical and non-clinical areas of a dental clinic.

Materials and Methods: In this cross-sectional study, 20 air samples were collected from various sections of the Dental School of Arak University of Medical Sciences. Sampling was performed using a pump equipped with a filter for two hours at a flow rate of 5 L/min and a height of 1.5 m above the floor. The samples were transported under a cold chain, the viral RNA was extracted, and then were analyzed using a specific RT-PCR kit.

Results: Out of 20 collected air samples, 3 samples (15%) tested positive for SARS-CoV-2 RNA. Two from clinical departments (restorative and fixed prosthodontics) and one from a non-clinical area
(pre-clinic).

Conclusion: The findings of this study indicated that SARS-CoV-2 RNA was detectable in some air samples from both clinical and non-clinical areas of the dental clinic. These results highlight the importance of strict adherence to infection control protocols across all sections of dental clinics to minimize the risk of airborne transmission.


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