Isolation, cloning and molecular analysis of ag85a and tb10.4 genes from Mycobacterium tuberculosis

Background: Novel tuberculosis (TB) vaccines that aim to boost and/or replace Bacillus Calmette-Guerin (BCG) are currently in development. DNA vaccines can stimulate both humoral and cell-mediated immunity in different animal models of TB and is thought to be a promising strategy in the development of new vaccines against TB. The aim of this study was to design and construct a DNA vaccine encoding ag85a and tb10.4 fusion genes of Mycobacterium tuberculosis.Materials and Methods: tb10.4 fragment was amplified by PCR and the product was digested with restrictionenzymes. Next, it was cloned into the pcDNA3.1+ plasmid. The ag85a gene and pcDNA3.1+/tb10.4 plasmid were digested by EcoRI and BamHI restriction enzymes. Constructed vector was sequenced. The molecular analysis was done using bioinformatics software. New chimeric vector containing ag85a-tb10.4 genes were purified. Expression of pcDNA3.1+/tb10.4-ag85a plasmid was confirmed in eukaryotic cells.Results: Fragments of 297 bp for tb10.4 and 1017 bp for ag85a were observed in agarose gel electrophoresis.Alignment of ag85a-tb10.4 genome sequence with reference genes in GenBank showed exact identities that indicate correction of all cloning procedures. Transfection of eukaryotic cells with pcDNA3.1+/tb10.4-ag85a vector and existence of tb10.4-ag85a fusion gene were both confirmed with RT-PCR.Conclusion: In this study, tb10.4 and ag85a genes were isolated from Mycobacterium tuberculosis H37Rv strain and cloned into pcDNA3.1+. Also, the capability of constructed vector in producing fusion ag85a-tb10.4 protein was confirmed with RT-PCR. pcDNA3.1+/tb10.4-ag85a vector can be used for further studies in future

Preferred Learning Styles among Ophthalmology Residents: An Iranian Sample

Purpose: This study was performed to assess the learning styles of a sample of Iranian residents through Kolb’s and VARK questionnaires. Methods: In this descriptive-analytical study, 45 ophthalmology residents of Mashhad University of Medical Sciences were enrolled. Kolb’s and VARK questionnaires were provided, and residents were oriented and guided on how to complete them. Results: Forty-three out of the forty-five ophthalmology residents completed the questionnaire (95.5% response rate). The preferred learning style among ophthalmology residents was assimilative (51.2%), followed by convergent (37.2%), accommodative (7.7%), and divergent (4.7%), based on Kolb’s questionnaire. According to the results of the VARK questionnaire, most ophthalmology residents were auditory learners (34.9%), followed by multimodal learners (30.2%). In addition, there was no significant relation between genders, stage of residency, and Kolb’s and VARK learning styles (P > 0.05 for all). Conclusion: The most preferred learning styles of ophthalmology residents were assimilative and auditory. Considering the dominant learning styles of learners and incorporating various teaching methods are recommended to enhance the learning among residents

High frequency of BRAF V600E mutation in Iranian population ameloblastomas

Ameloblastoma is a common locally invasive but slow-growing neoplasm of the jaws with an odontogenic origin. Association between BRAF V600E mutation and clinicopathologic features and behavior of ameloblastoma remains controversial. This study aimed to evaluate BRAF V600E gene mutation and expression of its related proteins with clinicopathologic parameters in conventional ameloblastoma. 50 Formalin-fixed paraffin-embedded blocks were included in this study. Immunohistochemistry was done using rabbit monoclonal BRAF V600E mutation-specific antibody VE1. Quantitative real-time polymerase chain reaction assay was used for evaluating of BRAF V600E mutation. Expression of BRAF V600E antibody was Positive in 42 out of 50 cases (84%). 46 (92%) out of 50 specimens showed BRAF V600E mutation. There were 13 cases of recurrence (26%). 3 out of 4 cases with negative mutations did not show recurrence. We report the highest frequency (92%) of BRAF V600E mutation in ameloblastomas in the Iranian population. Although there was not a significant association between BRAF V600E?positive immunoexpression and recurrence and clinicopathologic parameters, its high frequency could emphasize its role as a therapeutic marker in the future

Benign Cementoblastoma Involving Deciduous and Permanent Mandibular Molars: A Case Report

Cementoblastomas are rare benign odontogenic tumors. Diagnosis of these lesions must be made by an association of clinical, radiographic, and histopathological findings. Cementoblastomas rarely occur in both primary and permanent dentitions. We describe the sixth case of cementoblastoma in the literature with the involvement of both deciduous and permanent teeth. The aim of this case report is to present the clinicoradiopathologic features of a cementoblastoma in a 4.5-year-old boy with an unusual recurrence. The first clinical and radiographic features appeared on the deciduous mandibular second molar. The second lesion occurred 1 year after treatment at 5.5 years old, involving the permanent mandibular first molar, and a subsequent lesion was seen at age 8 years in the edentulous region of the extracted mandibular first molar. After the last surgery, there was no recurrence of the lesion at 6 months’ follow-up. Follow-ups of patients with cementoblastomas are highly recommended for an early detection of recurrence

Fascin Expression in Ameloblastoma, Odontogenic Keratocyst and Dentigerous Cyst

Objective: The purpose of this study was to assess and compare fascin expression in 4 lesions which differ in aggressiveness: odontogenic keratocyst, dentigerous cyst and two types of ameloblastoma (solid and unicystic), and to find out whether fascin expression is associated with aggressiveness of these lesions or not. Material and Method: Nine solid ameloblastomas , 12 unicystic ameloblastomas, 13 odontogenic keratocyst and 12 dentigerous cyst were assessed in this study. The slides were examined at x400 magnification. Finally the lesions were divided into two groups based on microscopic examination, "low expression" and "high expression". Results: There were no significant differences between the lesions, except that fascin expression was slightly higher in unicystic ameloblastomas in comparison to other groups in intensity and count of the immunostaining cells. Conclusion: The results of this study suggest that local aggressiveness does not result in fascin expression. We suggest more studies with more samples, assessing expression of different proteins be done in the future

Evaluation of squamous cell carcinoma antigen 1 expression in oral squamous cell carcinoma (tumor cells and peritumoral T-lymphocytes) and verrucous carcinoma and comparison with normal oral mucosa

Background: Squamous cell carcinoma antigen (SCCA) is used as a prognostic marker for recurrence of squamous cell carcinoma in various sites, including head and neck. Studies suggest that its high serum levels are correlated to some clinical features, such as nodal metastasis. However, it is still unknown if high SCCA in patients with SCCA tissue expression in tumor cells are related to peripheral T-lymphocytes. Therefore, we did this study to evaluate SCCA expression in squamous cell carcinoma and verrucous carcinoma and to compare it with normal oral mucosa, also investigating the correlation between serum-based and tissue-based antigen levels. Methodology: In this study, the immunohistochemistry (IHC) technique was used to determine the SCCA1 expression pattern in 81 specimens divided into 3 groups, including oral squamous cell carcinoma, verrucous carcinoma, and normal oral mucosa. Serum-based and tissue-based antigen levels of 20 oral squamous cell carcinoma cases were compared by the western blot assay. SCCA expression was also evaluated and compared in both tumor cells and peripheral T-lymphocytes by the immunofluorescence assay. Results: Our results showed that the SCCA levels in SCC specimens were significantly lower than in verrucous carcinoma and normal and hyperplastic oral mucosa specimens. We found no correlation between the IHC expression of SCCA and serum levels. SCCA was well expressed in both tumor cells and peripheral T-lymphocytes. Conclusion: Decreasing SCCA in SCC specimens suggested that SCC tumor cells may affect more than the serum levels of SCCA in some patients. In addition, expression of SCCA in peripheral T-lymphocytes showed that both tumor cells and T-lymphocytes may cause serum SCCA.&nbsp

Human Papillomavirus-Associated Oral Epithelial Dysplasia: A Practical Approach to Make the Diagnosis

Background: High-risk Human Papillomavirus (HPV) genotypes are found in malignant oral epithelial lesions, and HPV infection is proposed as a risk factor for initiating Squamous cell carcinoma (SCC) in the head and neck region. This study suggests a practical approach to detect HPV in HPV-associated oral epithelial dysplasia (HAOED).Methods: Fifty-four oral epithelial dysplasia specimens were examined, comprising twenty-seven cases diagnosed with high-grade dysplasia and twenty-seven cases diagnosed with low-grade dysplasia using a binary grading system. To assess the cases for HPV, the specimens were examined for p16 protein using an immunohistochemical (IHC) study, and then, the Chromatin In Situ Hybridization (CISH) test was performed for all positive cases. Chromatin Immunoprecipitation-Polymerase Chain Reaction (ChIP-PCR) was performed on CISH-positive specimens to assess the outcome. This cross-sectional study was conducted in 2020 at Tehran University of Medical Science. SPSS software version 22.0 was used to perform the Chi square or Fisher’s exact test to examine the relationship between variables (statistically significant level P0.99), and in the nine cases, undergone the ChIP-PCR study, two cases (22.2%) showed positivity for HPV-16, while one case (11.1%) demonstrated positivity for HPV-51.Conclusion: Regarding HAOED, here, we proposed a step-by-step combination approach using different diagnostic methods, including IHC for p16 protein, CISH, and ChIP-PCR based on a complementary algorithm

Possibility of the blood clot, thrombotic thrombocytopenia following injection of COVID-19-vaccine AstraZeneca; a systematic review

Introduction: Recently, it has been reported that the injection of vaccines such as the ChAdOx1 nCoV-19 (AstraZeneca) involves some rare cases of thrombocytopenia and blood clots, although the vaccines created immunity in people. Estimates of this phenomenon are not the same in different countries, probably due to age distribution and number. Objectives: This study attempted to study AstraZeneca’s rare side effects in people injected with this vaccine. Methods: This systematic study was conducted using articles published in 2021 under the title of blood clot and thrombocytopenia by AstraZeneca injection. The references and data were gathered through national and international sites such as Magiran, Google Scholar, PubMed, Web of Science, and Scopus. They were also gathered and examined using report cases and the available data on COVID-19 vaccine immunization in various countries. The keywords used mainly are COVID-19 vaccine, ChAdOx1 nCoV-19 vaccine, blood clots, thrombus, thrombotic, and thrombocytopenia. Eventually, 25 articles were searched and examined, of which 15 related ones were selected after reviewing and re-studying. While investigating the summary and method in those 15, they were filtered more accurately; finally, ten articles were chosen. Inclusion criteria consisted of all related articles and exclusion criteria contained articles that were less related to our research subject after purification or were redundant and not of high quality. Results: This study found that rare blood clot cases and thrombocytopenia were seen despite mild side effects after AstraZeneca injection. After assessing its benefits, adverse effects, and age distribution, the countries using AstraZeneca decided to continue using it. The main difference in reported statistics in these countries is due to the variety in the age and number of people receiving the vaccine. Conclusion: Blood clots and thrombocytopenia are among the rare side effects of the AstraZeneca vaccine. In different countries, the vaccine side effects vary depending on the age and number of participants. Anyway, according to the investigations conducted in this area, the highest records of these side effects are observed in Norway, which is still low. Overall, through studying this study and other similar ones, politicians, managers, and even ordinary people can be informed about the pros and cons of this vaccine

Rhabdomyosarcoma of the maxillary gingiva

Rhabdomyosarcoma is a malignant skeletal muscle neoplasm. The tumor is much more common in children, and the most frequent site is head and neck region. Since this tumor is less frequent than other neoplasms in oral cavity, the clinicians sometimes ignore it, working the patients up. Rhabdomyosarcoma is a high-grade malignancy with poor prognosis. Considering the aggressive behavior and various clinical or histopathologic presentations of the tumor, early diagnosis has a significant impact on the treatment outcome and prognosis of the patients. We highlight the importance of combining the clinical, radiographic, and histopathologic examination to obtain a definitive diagnosis in sarcomas of the head and neck region, especially rhabdomyosarcoma. A case of rhabdomyosarcoma of the maxillary gingiva is presented in a 32-year-old woman in which the primary incisional biopsy was erroneously interpreted as an inflammatory process and consequently, the accurate diagnosis postponed for about 10 months

Effect of Layering Technique on Push-Out Bond Strength of Composite Resin to Intracanal Dentin of Primary Anterior Teeth

Objectives: This in-vitro study aimed to compare the push-out bond strength of composite resin posts packed into the root canal of primary anterior teeth using two different layering techniques. Materials and Methods: Thirty-two primary anterior teeth were randomly divided into two groups. In group 1, after the preparation of post spaces, a posterior composite resin (Filtek P60) was packed in three horizontal layers by a composite condenser instrument with a cylindrical tip using the horizontal layering technique (HLT). In group 2, this was done using a condenser with a conical tip in three funnel-shaped layers according to the funnel-shaped layering technique (FSLT). Next, the specimens were subjected to push-out bond strength testing. Data were analyzed using t-test and the Kaplan-Meier curves. Results: The mean±standard deviation (SD) bond strengths of composite resin posts were 8.46±3.45 MPa and 7.7±2.24 MPa for the HLT and FSLT, respectively; the difference was not statistically significant (P=0.46). Conclusions: The layering technique by which composite resin was packed into the root canal of primary anterior teeth (HLT versus FSLT) had no significant effect on the push-out bond strength of composite resin posts.