A study on genetic and mutans streptococcal transmissibility of dental caries.

Background: Dental caries is characterized by an interplay between environmental and genetic factors. Aim: The aim of this study was to analyse the transmissibilities of high caries risk chromosomal loci at 5q 12.1-13.3 and low caries risk chromosomal loci at 13q31.1 and Streptococcus mutans (S. mutans) in family units. Materials: This prospective cohort study was performed on 56 families grouped into four: (a) Group I: 18 families of children with caries affected primary teeth; (b) Group II: 21 families of children with caries in permanent teeth; (c) Group III: 6 families of children with no caries in primary teeth and (d) Group IV: 12 families of children with no caries in permanent teeth. Blood, saliva and plaque samples were collected from consenting study participants. Isolated DNAs were subjected to polymerase chain reactions using suitable primers. Data collected was analysed with ANOVA and Chi-squared test. Results: Wide expression of chromosome loci 5q12.1-13.3 was obtained in both blood and saliva samples. For chromosome loci 13q31.1, no expression was found in saliva samples, hence indicating its local absence. For the GtfB expression, transmissibility was common for a single band expressing S. mutans. Conclusion: This study reflects upon newer findings in the field of genetic research on dental caries.

Diffused mixed B-cell non-Hodgkin lymphoma of mandible.

Lymphomas are the third-most common cancer of the oral cavity after squamous cell carcinomas and salivary gland tumors. It is characterized by proliferation of lymphoid cells and their precursor. Diffuse B-cell non-Hodgkin lymphoma is the most common histological type of lymphoma in the head-and-neck region and most commonly affects older men in their seventh decade of life.

Saliva as a forensic tool.

Forensic science is a branch that deals with a wide plethora of areas such as anthropology, migration studies and criminology. Various biological samples have been utilized to assist a scientist towards getting answers to the myriad of questions in the field. Saliva is an easily available source from victim as well as aggressors, parent-child and siblings. Various tests have been devised to aid in identifying salivary sample constituents. This paper deals with the wide utility of saliva as a forensic tool.

Hybrid ameloblastoma: a mystified histopathological entity.

Ameloblastoma a benign neoplasm of the maxillofacial region has been divided into various histopathological types by WHO. A more complex and confusing type includes hybrid type, which as the name suggest include more than two variants mostly histopathological. Various authors have reported cases of this type but the exact histopathological features are still unclear and each case that is being reported add to the literature, which further strengthens its histopathological feature. Also, this is a lesion whose clinical and radiographical features are similar to all the variants and a definitive diagnosis is achieved by histopathology only. Here, we present a case of hybrid ameloblastoma with striking and unique histopathological features.

Chondrosarcoma of maxilla.

Chondrosarcoma is a rare malignant cartilaginous tumor of the head and neck region. It is a slow-growing tumor and is mostly detected in the anterior maxilla and the base of the skull. We report a case of "Grade II Chondrosarcoma" of the posterior right side of the palate invading maxillary sinus and perforating the floor of the orbit.

Telomeres in health and disease.

Telomeres are repetitive ribonucleoprotein complexes present at ends of chromosomes. To synthesize this manuscript, a thorough literature search was done using PubMed, MEDLINE and Cochrane review for English-language literature and data available from the period of 2005-2016 were analyzed for manuscript writing. Telomeres help in maintaining the cellular health, inbuilt cellular mechanisms, metabolism and normal cell cycle. Telomerase is a specialized enzyme that possesses catalytic subunits - reverse transcriptase, Terc and dyskerin. Mutations affecting telomere or any component of telomerase enzyme result in disorders such as dyskeratosis congenita, aplastic anemia, myelodysplastic syndromes and leukemias. Thus, it is important to understand the telomere biology so as to deal with normal physiologic processes such as apoptosis, aging and senescence and tumor development.

Transmission of mutans streptococci in mother-child pairs.

BACKGROUND & OBJECTIVES: Dental caries is an infectious, transmissible disease. Maternal transfer of mutans streptococci (MS) has been a subject of research. The aim of this study was to evaluate the transmission of MS from mother to children through genetic analysis. METHODS: Thirty mother-child pairs were included and divided into three groups according to the age of the children. Saliva samples were collected and MS colonies from each mother-child pair were isolated. After inoculation and incubation, MS colonies were submitted to amplification technique by polymerase chain reaction (PCR) for identification and arbitrarily primed PCRs (AP-PCRs) to determine various MS genotypes. RESULTS: From birth to six months of age, 30 per cent of children exhibited MS colonization, and by the age of 30 months, 100 per cent harboured the bacteria (P < 0.001). Factors associated with MS colonization were eruption of teeth (P < 0.001), feeding habits with mean colony count being significantly lower in breast-fed as compared to bottle-fed children (P < 0.001) and a significant association between mean MS count of child and mother's practice of sharing spoon with child (P < 0.001). The AP-PCR fingerprinting profile analysis showed 17 MS groups (clusters) containing identical or highly related isolates in mother-child pairs with a high level of similarity (77.27 %). INTERPRETATION & CONCLUSIONS: The presence of matching MS genotypes suggested vertical transmission from mothers to children. Feeding habits, gum cleaning and number of erupted teeth in children had significant effect on MS colonization. There is a need to develop strategies to present MS colonization in children.

Artefacts in histopathology.

Histopathology is the science of slide analysis for the diagnostic and research purposes. However, sometimes the presence of certain artefacts in a microscopic section can result in misinterpretations leading to diagnostic pitfalls that can result in increased patient morbidity. This article reviews the common artefacts encountered during slide examination alongside the remedial measures which can be undertaken to differentiate between an artefact and tissue constituent.

Mechanisms of resistance against cancer therapeutic drugs.

Cancer is the manifestation of multiple dysregulated cellular pathways. Treatment protocols engaged in treating these diseases involve mainly the cell cycle regulating genes/proteins, DNA synthesis and repair, protein synthetic machinery, apoptotic and proliferation activity and cytoskeletal framework. Some of the traditional therapeutic strategies have over the years developed resistance making cure difficult to achieve. This paper analyzes the mechanisms employed by various cancers that render them resistant against therapeutic drugs.

Reliability of sexual dimorphism in blood.

BACKGROUND: Demonstration of sex chromatin forms an important aspect of human genetics. It also establishes the interrelationship between sex chromatin and an inactive X-chromosome. The term "sex chromatin" in blood refers to the "Drumsticks of polymorphonuclear leukocytes" or "Davidson's bodies". OBJECTIVE: This correlative study evaluates the presence of these drumsticks quantitatively and also highlights the concept of blood chimaerism in humans. METHOD: Leishman-stained peripheral blood smears from 60 individuals (30 males and 30 females) were obtained and studied under bright-field microscope (40X) for presence of Drumstick appendages. RESULTS AND CONCLUSION: On comparing mean numbers of Davidson's bodies in females and males, an extremely significant correlation (P < 0.0001) was seen. Hence, it could be surmised that the presence of appendages in neutrophils (Drumstick bodies) can be useful in gender differentiation.

Dimensional analysis of various rugae patterns in north Indian population subset.

INTRODUCTION: Rugae patterns are significant markers for analyzing anteroposterior changes in adolescence, and forensic investigations. AIM: The purpose of this study was to ascertain the gender-wise predisposition of rugae patterns and to analyze anteroposterior alterations along with any developmental changes in palatal depth. MATERIALS AND METHODS: One hundred pre-treatment study cast models were obtained from the archives of the Department of Orthodontics, M.M. CDSR, Mullana. Parameters employed were: Division of medial palatal region into "a": Distance between incisive papilla length and anterior limit of the anteriormost rugae; "b": Distance between incisive papilla and most posterior rugae limits; measurement of Lateral rugae dimensions and palatal depth. STATISTICAL ANALYSIS: Mean ± S.D. values were obtained and 'P' values calculated. RESULTS: Comparison of "a" and "b" showed a significant difference in the P values between the age-groups 12-13 years and >14 years. Rugae patterns with separate origins showed a predisposition for female gender. CONCLUSION: A significant change in the anteroposterior medial rugae dimensions was seen in adolescent age groups alongside no variation in palate depth. Hence, it can be concluded that differential growth potential is present in the premaxilla and can cause shift in medial palatal dimensions without altering the rugae patterns and palatal depth.

Quantitative role of mast cells in odontogenic cystic enlargement

Aim: Mast cells have been hypothesized to play a significant role in pathogenesis of odontogenic cysts. The aim of this study was to evaluate mast cell distribution in cystic lining and the capsule to formulate a mechanism of cystic expansion. Methods: Ten formalin-fixed paraffin embedded tissue blocks each of OKC, dentigerous and radicular cysts were selected. Toluidine blue staining (1% in 1% NaCl solution) was done in 5µm thick sections and counting performed in 10 areas using an ocular grid. Areas counted were divided into 4 zones: intraepithelial, subepithelial, intermediate and deep zones (Group I, II, III and IV respectively). Statistical analysis: Mean ±S.D. was calculated in each group followed by paired ‘T’ test. Results: Mast cells had greatest concentration in subepithelial zone. ‘T’ test showed no significant differences between group I and II zones in OKC but a highly significant difference between groups I and II in dentigerous cyst. Radicular cysts showed a significant difference between groups II and III. Conclusion: Mast cell degranulation releases numerous hydrolytic enzymes that facilitate breakdown of capsular matrix increasing the hydrostatic pressure due to raised osmolality. Influx of tissue fluids results in their enlargement coupled with resorption at the bone-cyst interface.