Adequacy of Direct Digital Radiography (DDR) Compared to Conventional Radiography in Detection of Mechanically Created Bone Lesions.

Background and Aim: Early diagnosis of bone pathologic lesions is of paramount importance in enabling the clinician to provide immediate and appropriate dental treatment. Conventional radiographs have always been used as the primary and fundamental means of diagnosis, treatment and follow up of endodontic lesions. In recent years, digital imaging has gained high popularity for diagnostic purposes. The aim of this study was to assess the accuracy of digital radiographic imaging compared to conventional radiography in detecting mechanically created jaw bone lesions. Materials and Methods : This experimental study was conducted on the lower jaw of a cow cadaver. Mechanical lesions with different depths (0.5, 1, 1.5, 2, 2.5, 3, 4,5mm)were drilled into the jaw with a surgical bur (021). A digital radiograph followed by a conventional image with E-speed film were obtained and the images were evaluated by five examiners. Wilcoxon Signed-Ranks test was used for statistical analysis. Results: According to the results of this study, examiners were more successful in detecting lesions with DDR than with conventional radiography.The mean value and standard deviation of detection score were 1/25 ± 0/98 for conventional and 1/85 ± 0/53 for digital methods. This difference was statistically significant. (P< 0.001) Conclusion : The adequacy of digital radiography in detection of bone lesions is much higher than conventional radiography. Digital images are recommended for diagnostic purposes

Myocilin Mutations Are Not a Major Cause of Primary Congenital Glaucoma in Iranian Patients

Purpose: To assess the frequency of mutations in the Myocilin (MYOC) gene in Iranian patients affected with primary congenital glaucoma (PCG). Methods: The individuals evaluated herein are among a larger cohort of 100 patients who had previously been screened for CYP1B1 mutations. Eighty subjects carried mutations in CYP1B1, but the remaining 20 patients who did not, underwent screening for MYOC mutations for the purpose of the study. MYOC exons in the DNA were polymerase chain reaction (PCR) amplified and sequenced. Sequencing was performed using PCR primers, the ABI big dye chemistry and an ABI3730XL instrument. Sequences were analyzed by comparing them to reference MYOC sequences using the Sequencher software. Results: Four MYOC sequence variations were observed among the patients, but none of them were considered to be associated with disease status. Three of these variations were single nucleotide polymorphisms already reported not to be disease causing, the fourth variation created a synonymous codon and did not affect any amino acid change. Conclusion: In this cohort, MYOC mutations were not observed in any Iranian subject with PCG. It is possible that in a larger sample, a few subjects carrying disease causing MYOC mutations could have been observed. But our results show that the contribution of MYOC to PCG status in Iran is small if any

Screening of common CYP1B1 mutations in Iranian POAG patients using a microarray-based PrASE protocol

Purpose: The gene coding cytochrome P4501B1 (CYP1B1) has been shown to be a major cause of primary congenital glaucoma in the Iranian population. More recently it was shown to also be important in juvenile-onset open angle glaucoma (JOAG). We aimed to further investigate the role of CYP1B1 in a larger cohort of primary open angle glaucoma (POAG) patients which included late-onset patients. We also aimed to set up a microarray based protocol for mutation screening with an intent of using the protocol in a future population level screening program. Methods: Sixty three POAG patients, nine affected family members, and thirty three previously genotyped primary congenital glaucoma (PCG) patients were included in the study. Clinical examination included slit lamp biomicroscopy, IOP measurement, gonioscopic evaluation, fundus examination, and measurement of perimetry. G61E, R368H, R390H, and R469W were screened by a protocol that included multiplexed allele specific amplification in the presence of a protease (PrASE), use of sequence tagged primers, and hybridization to generic arrays on microarray slides. The entire coding sequences of CYP1B1 and myocilin (MYOC) genes were sequenced in all individuals assessed by the microarray assay to carry a mutation. Intragenic single nucleotide polymorphism (SNP) haplotpes were determined for mutated alleles. Results: Genotypes assessed by the array-based PrASE methodology were in 100 concordance with sequencing results. Seven mutation carrying POAG patients (11.1) were identified, and their distribution was quite skewed between the juvenile-onset individuals (5/21) as compared to late-onset cases (2/42). Four of the seven mutation carrying Iranian patients harbored two mutated alleles. CYP1B1 mutated alleles in Iranian PCG and POAG patients shared common haplotypes. MYOC mutations were not observed in any of the patients. Conclusions: The PrASE approach allowed reliable simultaneous genotyping of many individuals. It can be an appropriate tool for screening common mutations in large sample sizes. The results suggest that CYP1B1 is implicated in POAG among Iranians, notably in the juvenile-onset form. Contrary to POAG patients studied in other populations, many mutation harboring Iranian patients carry two mutated alleles. We propose an explanation for this observation. © 2008 Molecular Vision

Glaucoma in Iran and contributions of studies in Iran to the understanding of the etiology of glaucoma

Epidemiologic and genetic/molecular research on glaucoma in Iran started within the past decade. A population-based study on the epidemiology of glaucoma in Yazd, a city in central Iran, revealed that 4.4% of studied individuals were affected with glaucoma: 1.6% with high tension primary open angle glaucoma (POAG), 1.6% with normal tension POAG, and 0.4% each with primary angle closure glaucoma (PACG) and pseudoexfoliation glaucoma (PEXG), and other types of secondary glaucoma. Two notable observations were the relatively high frequency of normal tension glaucoma cases (1.6%) and the large fraction of glaucoma affected individuals (nearly 90%) who were unaware of their condition. The first and most subsequent genetic studies on glaucoma in Iran were focused on primary congenital glaucoma (PCG) showing that cytochrome P450 1B1 (CYP1B1) is the cause of PCG in the majority of Iranian patients, many different CYP1B1 mutations are present among Iranian patients but only four mutations constitute the vast majority, and the origins of most mutations in the Iranians are identical by descent (IBD) with the same mutations in other populations. Furthermore, most of the PCG patients are from the northern and northwestern provinces of Iran. A statistically significant male predominance of PCG was observed only among patients without CYP1B1 mutations. Clinical investigations on family members of PCG patients revealed that CYP1B1 mutations exhibit variable expressivity, but almost complete penetrance. A great number of individuals harboring CYP1B1 mutations become affected with juvenile onset POAG. Screening of JOAG patients showed that an approximately equal fraction of the patients harbor CYP1B1 and (myocilin) MYOC mutations; MYOC is a well-known adult onset glaucoma causing gene. Presence of CYP1B1 mutations in JOAG patients suggests that in some cases, the two conditions may share a common etiology. Further genetic analysis of Iranian PCG patients led to identification of Latent-transforming growth factor beta-binding protein 2 (LTBP2) as a causative gene for both PCG and several diseases which are often accompanied by glaucomatous presentations, such as Weill-Marchesani syndrome 3 (WMS3). The findings on LTBP2 have contributed to recognize the importance of the extracellular matrix in pathways leading to glaucoma

A possible role for LTBP2 in the etiology of primary angle closure glaucoma

Purpose: To assess the association of LTBP2 mutations with primary angle closure glaucoma (PACG). Methods: We studied 54 unrelated patients with PACG and one individual with pseudoexfoliation accompanied with angle closure glaucoma; these consisted of 28 female and 27 male subjects aged 27 to 82 (mean, 63) years. The 36 exons and flanking intronic sequences of LTBP2 in all patients were amplified by PCR and sequenced by the Sanger protocol. The sequences were compared to LTBP2 reference sequences. A total of 100 to 400 controls aged at least 60 years old were screened for various variations. Results: Out of 24 observed sequence variations, ten were in amino acid coding regions; of these four created synonymous codons while six caused amino acid changes. Based on allele frequencies, biochemical parameters, absence in control individuals, evolutionary conservation of affected amino acids, and bioinformatic predictions on the effects on protein function, it was concluded that only two mutations causing p. Gln1417Arg and p. Gly1660Trp may contribute to PACG. The p. Gly1660Trp mutation was observed in a patient with both PACG and PEX syndrome. P. Gln1417Arg had previously been reported only in a subject with POAG. Conclusion: LTBP2 may contribute to PACG. This finding emphasizes that there may be an overlap in the etiology of various forms of glaucoma and the overlaps likely contribute to common features in various forms of glaucoma

The predicting model of math anxiety: The role of classroom goal structure, self-regulation and math self-efficacy

AbstractThe purpose of the present study was to examine a predicting model of high school students’ math anxiety based on classroom goal structure, self-regulation and math self-efficacy. For this reason 436 first grade male high school students were selected through multiple cluster sampling. They completed a questionnaire consisting of perceived classroom goal structure (Midgley et al. 2000), Math anxiety (Bai et al. 2009) and researcher-made math self-efficacy scale. Data was analyzed using path analysis technique. Results indicated that mastery and performance-approach structures negatively influence math anxiety, directly and indirectly. All goal structures have a positive effect on self-regulation and performance-approach structure affects math selfefficacy positively, performance-avoidance structure affects it negatively, however. Math self-efficacy affects math anxiety directly and negatively, while negative effect of self-regulation is indirect through math self-efficacy. The mediating role of selfregulation and math self-efficacy in relationship between classroom goal structure and math anxiety was confirmed

An environmentally safe approach for the facile synthesis of anti-mutagenic fluorescent quantum dots: Property investigation and the development of novel antimicrobial applications

Quantum dots as nanocrystals of semiconductor materials are synthesized with different methods. The green synthesis of fluorescent quantum dots using natural stabilizing agents has attracted much attention. This research aims to study the ability of Teucrium polium L. extract to green synthesize fluorescent silver quantum dots (AgQDs). The green synthesis of AgQDs was proved using UV–Visible spectrophotometer, Fourier Transform Infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), Photoluminescence (PL) analysis, and Dynamic Light Scattering (DLS). According to the findings, the shape of fluorescent AgQDs was spherical, and the maximum abundance of particle size distribution was between 3 and 5 nm. Thereupon, antimicrobial, anti-mutagenicity, anticancer, and antioxidant activities were evaluated to distinguish the biological features of AgQDs. Gram-positive bacteria (S. epidermidis, MIC: 31.25 μg/ml) and fungi (C. albicans, MIC: 31.25 μg/ml) were the most susceptible to AgQDs. Moreover, the AgQDs solution had higher antimicrobial activity than AgNO3. The Ames test demonstrated that AgQDs have considerable anti-mutagenic activities (% mutagenicity inhibition greater than 40) and are not mutagenic. The anticancer activity of AgQDs was distinguished using MTT and brine shrimp lethality (BSL) assays. The analysis indicated that AgQDs had a strong potential for cytotoxicity (BSL: LC50 = 2.4 μg/ml, MTT: IC50 = 0.8 μg/ml). Further, AgQDs were used for bioimaging human ovarian OVCAR3 cells, and their biocompatibility was remarkable. In the DPPH assay, AgQDs displayed high antioxidant activity (89.9% inhibition). Using AgQDs to coat materials to develop antibacterial agents revealed significant activity against C. albicans and S. epidermidis strains. Our results indicate that T. polium is a promising source for synthesizing AgQDs. Due to the potent bioactivities of AgQDs, they can be used in medicine and industry