ABSTRACT
OBJECTIVE: Nucleolar organizer regions are loops of DNA containing ribosomal RNA genes and presumably are associated with ribosomal RNA activity, protein synthesis, and cell proliferation. Argyrophilic nucleolar organizer region (AgNOR) count has been suggested as an objective method in differentiating dysplastic lesions from non-dysplastic lesions. MATERIALS AND METHODS: This descriptive study was done on archival paraffin blocks (n = 60), consisting of 10 normal human oral epithelium, 22 cases of non-dysplastic leukoplakia (NDLK), and 28 cases of dysplastic leukoplakia (DLK). The AgNORs were counted with the aid of a manual using conventional light microscopy and photographs of the same were taken and analyzed using Image Pro Express 6.0 (Media Cybernetic Inc., USA) for windows. RESULTS: The mean AgNOR count per nucleus was found to be higher in patients with DLK as compared to NDLK and controls using both manual counting and image analysis method and on comparing both the techniques, image analysis provide a more accurate reflection of AgNOR counts than manual counting. CONCLUSION: To conclude, reliability of computerized image technique of AgNOR count is the most appropriate marker to differentiate between dysplastic and NDLK. Computer-assisted image analysis system was found to be an effective tool in achieving high reproducibility as compare to manual.
Subject(s)
Antigens, Nuclear/biosynthesis , Leukoplakia, Oral/genetics , Molecular Imaging , Mouth Neoplasms/genetics , Antigens, Nuclear/genetics , Cell Proliferation/genetics , Epithelium/pathology , Female , Humans , Image Processing, Computer-Assisted , Leukoplakia, Oral/diagnosis , Leukoplakia, Oral/pathology , Male , Mouth Neoplasms/diagnosis , Mouth Neoplasms/pathologyABSTRACT
Advances in biotechnology have brought gene therapy to the forefront of medical research. The concept of transferring genes to tissues for clinical applications has been discussed nearly half a century, but the ability to manipulate genetic material via recombinant DNA technology has brought this goal to reality. The feasibility of gene transfer was first demonstrated using tumour viruses. This led to development of viral and nonviral methods for the genetic modification of somatic cells. Applications of gene therapy to dental and oral problems illustrate the potential impact of this technology on dentistry. Preclinical trial results regarding the same have been very promising. In this review we will discuss methods, vectors involved, clinical implication in dentistry and scientific issues associated with gene therapy.
Subject(s)
Dentistry , Genetic Therapy , Genetic Engineering , HumansABSTRACT
BACKGROUND: Oral cancer is one of the most debilitating and disfiguring of all malignancies; it is one of the most frequently occurring cancers in the body. The high incidence of oral cancer in India has been attributed to widespread tobacco usage among the population either in chewable or smoked form. AIM: In the current study, we retrospectively analyzed 191 cases (2007-2009) of potentially malignant oral lesions, which had been biopsied in our hospital, in order to assess their relationship with tobacco usage. MATERIALS AND METHODS: Based on the histopathology, these lesions were classified as high-risk lesions (HRL), low-risk lesions, and questionable risk lesions. The data obtained were then analyzed to find out the correlation between the occurrence of risk level with various demographic parameters such as age and gender as well as with type, frequency, and duration of tobacco habit. RESULTS: Out of 191 cases, 122 patients reported with tobacco habit (chewers, smokers, and both) and frequency (<5 and >5 packets/day) were seen in 109 cases and duration (<5 and >5 years) seen in 99 cases. These parameters were correlated with histopathological diagnosis and results showed that both the groups came under the high-risk category. Further analysis of decategorized group (age and gender) was also done. CONCLUSION: Analysis showed that overall histopathologically diagnosed HRLs were seen more in males and smokers compared to female and chewers, respectively.
ABSTRACT
BACKGROUND: Silver stainable nucleolar organizer regions (AgNORs) are replicatory markers which may have a place in objectively characterizing dysplasia. MATERIALS AND METHODS: A study of various morphometric parameters related to AgNORs was performed in basal and parabasal layers of normal human oral epithelium, nondysplastic leukoplakia, and dysplastic leukoplakia employing photomicrographs of silver stained paraffin embedded sections using image analysis, to assess the usefulness of these parameters in distinguishing dysplastic leukoplakia from nondysplastic oral leukoplakia. RESULTS: Out of various mean AgNOR related parameters, AgNOR count, area, perimeter, and proportion were found to be higher in dysplastic leukoplakia as compared to nondysplastic leukoplakia. On statistical analysis, AgNOR count showed statistically significant differentiation between dysplastic and nondysplastic leukoplakia. While other parameters can distinguish normal oral epithelium from dysplastic and nondysplastic leukoplakia. CONCLUSION: To conclude, the AgNOR count is the most appropriate marker to differentiate between dysplastic and nondysplastic leukoplakia.
