Unveiling the Biocontrol Potential of Rhizoplane Bacillus Species against Sugarcane Fusarium Wilt through Biochemical and Molecular Analysis.

BACKGROUND: Biocontrol is regarded as a viable alternate technique for managing sugarcane wilt disease caused by Fusarium sacchari. Many fungal antagonists against F. sacchari, have been reported, but the potential of bacterial antagonists was explored to a limited extent, so the present study evaluated the antagonistic potential of rhizoplane Bacillus species and their mode of action. RESULTS: A total of twenty Bacillus isolates from the rhizoplane of commercially grown sugarcane varieties were isolated. The potential isolate SRB2 had shown inhibition of 52.30, 33.33, & 44.44% and SRB20 of 35.00, 33.15, & 36.85% in direct, indirect, and remote confrontation respectively against F. sacchari. The effective strains were identified as Bacillus inaquosorum strain SRB2 and B. vallismortis strain SRB20, by PCR amplification of 16S-23S intergenic region. The biochemical studies on various direct and indirect biocontrol mechanisms revealed the production of IAA, Protease, Cellulase, Siderophores, and P solubilization. The molecular analysis revealed the presence of antimicrobial peptides biosynthetic genes like fenD (Fengycin), bmyB (Bacyllomicin) ituC (Iturin) and spaS (Subtilin) which provided a competitive edge to these isolates compared to other Bacillus strains. Under greenhouse experiments, the sett bacterization with SRB2, significantly (P < 0.001) reduced the seedling mortality by > 70% followed by SRB20 in F. sacchari inoculated pots. CONCLUSION: The study revealed that the isolates B. inaquosorum SRB2 and B. vallismortis SRB20 can be used as potential bioagents against sugarcane Fusarium wilt.

Glandular odontogenic cyst: Review of literature and report of two cases.

Glandular odontogenic cyst (GOC) is a rare developmental odontogenic cyst from the cell rests of Serres. GOC is locally aggressive with a tendency toward recurrence. The most common site of occurrence is the anterior mandible with an asymptomatic presentation. Radiographically, it presents as unilocular or multilocular radiolucency. It bears histopathological resemblance to low-grade mucoepidermoid carcinoma. We report two cases of GOC occurring in a 16-year-old and a 33-year-old male patient with a review of the clinical presentation, histopathological features, and diagnostic aspects of GOC reported so far in literature.

Diagnostic Utility of Gram Stain for Oral Smears - A Review.

For rapid and successful treatment of infectious diseases, detection of the presence of microorganisms is essential. Traditional culture-based approaches are limiting and time consuming for microbial identification. The most popular staining technique for identifying Gram-positive and Gram-negative microorganisms in various tissues is called Gram staining. This method is utilized in both clinical practice and research. Gram staining of the oral smears is the preliminary step in the identification of any pathological shift in normal oral microbiota. This review discusses the principle of gram stain emphasizing its significance in diagnostic utility for oral smears.

Comparative Evaluation of Buccal Exfoliated Cells in Individuals with Diabetes Mellitus and Healthy Controls: A Cytomorphometric Analysis.

Background: Diabetes mellitus is the third most frequent cause of mortality and morbidity worldwide. Patients with diabetes exhibit a variety of oral symptoms, and hence the early detection of this condition can be addressed by a dentist. Aim: The current study aimed to study the cytomorphometric alterations of buccal exfoliated cells in individuals with type II diabetes mellitus. Methodology: The study included thirty diabetics and thirty healthy controls. The smears were obtained from the buccal mucosa and stained with Papanicolaou stain and hematoxylin and eosin stain. The presence of inflammatory cells, microbial carriage, nuclear enlargement, and perinuclear halo and binucleation were examined on the slides. Cellular and nuclear parameters were quantitatively measured using Image J software. Statistical analysis was done using SPSS software, and the Student's t-test was employed. Results: No inflammatory cells or microbes were observed in Group I individuals; however, the perinuclear halo was observed in 16.6% and binucleated cells in 3.3% of the controls. Inflammatory cells, consisting mainly of neutrophils and lymphocytes were seen in 40%, microbial carriage in 26.6%, perinuclear halo in 73.3%, and binucleated cells in 36.6% of the diabetic patients. The mean nuclear diameter, area, and nuclear-cytoplasmic ratio were significantly high in diabetic patients when compared to healthy controls. Conclusion: Oral exfoliated mucosal cells of patients with diabetes mellitus exhibit distinct cytomorphometric alterations such as increased nuclear diameter, nuclear area, and nuclear-cytoplasmic ratio.

Radiologic-Pathologic correlation of Pindborg tumor of maxilla with extension to maxillary sinus, nasal cavity, and infraorbital margin: A case report.

Calcifying epithelial odontogenic tumor is a benign epithelial odontogenic tumor thought to originate from the stratum intermedium. Clear cell type, Langerhans cell/non-calcified type, and cystic/microcystic are the three recently recognized histological subtypes of CEOT in the 5th edition of the World Health Organization Classification of Head and Neck Tumors. Almost 350-400 cases of CEOT have been reported in literature, accounting for less than 1% of the reported cases of odontogenic tumors. We are reporting a case of Pindborg tumor of the maxilla with extension to the maxillary sinus, nasal cavity, and infraorbital margin, with an emphasis on radiographic and histopathologic presentation.

CD44 Expression in Oral Lichen Planus and Related Lesions-An Immunohistochemical Study.

Background: Cluster of differentiation 44 (CD44) is a cell surface adhesion protein involved in the progression and metastasis of oral squamous cell carcinoma. The current study aims to evaluate the expression of CD44 in oral lichen planus and related lesions and thereby assess the relative risk of malignant transformation of these lesions. Materials and Methods: Formalin-fixed paraffin-embedded tissue blocks of 10 oral lichen planus (Group 1), 10 oral lichenoid lesions (Group 2), 8 with oral lichen planus with dysplasia (Group 3), and 5 with lichenoid dysplasia (Group 4) were included in the study. Immunostaining was done for the tissue sections using CD44 mouse monoclonal antibody. Staining density, staining intensity, and immunoreactive scores of CD44 were evaluated in all four groups. Statistical analysis was done by Statistical Package for the Social Sciences® software and the Kruskal-Wallis test was used. Results: CD44 staining pattern of lichenoid dysplasia and lichen planus with dysplasia changed from membranous to cytoplasmic. The membranous CD44 immunoreactivity was mild with a score of 2.25 for Group 3 and 1.6 for Group 4 whereas moderate for other groups with a P-value of 0.009. The cytoplasmic immunoreactivity was significantly high in Group 3 (5.3 ± 2.6) followed by Group 4 (3.2 ± 1.2), Group 2 (1 ± 1.8), and Group 1 (0.7 ± 1.3) with a P-value of 0.001. Conclusion: The CD44 membranous immunoreactivity scores were low while the cytoplasmic immunoreactivity was high in oral lichen planus with dysplasia and oral lichenoid dysplasia when compared to oral lichen planus and oral lichenoid lesions. CD44 immunostaining pattern can help in assessing the malignant transformation of oral lichen planus or lichenoid lesions.

Paradental cyst with hyaline ring granuloma masquerading as pericoronitis.

Paradental cyst is an odontogenic cyst associated with pericoronitis in partly erupted mandibular third molars. It is an inflammatory cyst common among the mandibular molars. The cyst is most commonly seen on the distal or distobuccal aspect of the third molars. The angle of tooth and food impaction has been postulated to be responsible for the development of the cyst in third molars. The source of the epithelium has been reported as reduced enamel epithelium. The paradental cyst is frequently misdiagnosed as a radicular cyst or dentigerous cyst. We report a case of paradental cyst in a patient with partially erupted mandibular third molar with food impaction and resulting hyaline ring granuloma.

Clinicopathological characteristics of oral squamous cell carcinoma arising from oral submucous fibrosis: A systematic review.

Introduction: Oral submucous fibrosis (OSMF) is considered to be a potentially malignant oral disorder with high risk of malignant transformation. Oral squamous cell carcinoma (OSCC) arising from OSMF has peculiar clinical and histopathological features. Aim: To assess the clinicopathological features of OSCC arising in the background of OSMF in an attempt to identify the patients with OSMF who are at increased risk of developing OSCC. Methodology: A systematic review was performed based on PRISMA guidelines to include articles published until May 2021 in English, relating the clinicohistopathological characteristics of OSCC arising from OSMF (OSMF-OSCC) or OSMF associated with OSCC (OSCC-OSMF). All the eligible articles were analyzed and relevant data were extracted. Results: Seventeen articles were included for systematic review after following strict inclusion and exclusion criteria. The malignant transformation rate of OSMF-OSCC ranged from 1.9 to 9.13 and the prevalence of OSCC-OSMF ranged from 2.8 to 66. The mean age of the patients ranged from 36.6 years to 47.2 years and buccal mucosa was the common site to be affected. Majority of the OSCC-OSMF was well-to-moderately differentiated and majority of them did not metastasize to the lymph nodes. Conclusion: OSCC associated with OSMF presents at a younger age with early tumor stage, better differentiation, and better prognosis when compared to OSCC not associated with OSMF. However, more multicentric prospective studies with large sample size are required to determine the true biologic behavior of OSCC arising in the background of OSMF to establish less aggressive treatment strategies considering them as a separate entity.

Intraoral neurofibroma: A case report with emphasis on immunohistochemical markers.

ABSTRACT: A neurofibroma is a benign peripheral nerve sheath tumor. They occur in combination with neurofibromatosis or as a solitary mass. Intraoral neurofibromas pose diagnostic difficulties, suggesting the appropriate use of diagnostic markers and clinical knowledge. Here, we report a case of intraoral neurofibroma in a 57-year-old female who reported with the complaint of painless growth in the lower left back tooth region for the past three years. Based on the clinical features, provisional diagnosis of traumatic fibroma was made. However, histopathology proved it to be a benign spindle cell lesion; upon further investigation by immunohistochemistry, it was diagnosed to be a case of neurofibroma.

Phyto-intruders in oral tissues: A polarized light microscopic study.

OBJECTIVES: Foreign body reactions are common in the oral cavity due to its proximity to the external environment. Rarely, foreign body of plant origin may be encountered in the histopathological sections making the diagnosis problematic. The aim of the present study was to analyze the histological features of various products of plant origin emphasizing on the pathogenesis of tissue reaction occurring in response to their implantation. METHODS: This observational study included various plant products or phytoproducts commonly consumed in South Indian diet such as rice, curry leaves, coriander leaves, spinach leaves, coconut, green chilli, onion, French beans, urad dal, lentil beans, mustard seed, ginger, and garlic. Formalin-fixed specimens were routinely processed and stained with hematoxylin and eosin. The slides were viewed under light microscope and polarized microscope and evaluated by two oral pathologists. RESULTS: Each of the phytoproducts had distinctive histological appearance and exhibited positive birefringence. Phytoproducts such as rice, curry leaves, French bean, onion, and green chilli resembled pathological structures such as calcifications, ghost cells, clear cells, atypical adipocytes, and fungal hyphae, respectively. CONCLUSIONS: Plant products appear as puzzling structures in histological section posing difficulties to the pathologist. Recognition of these structures as foreign body based on their histological appearance is inevitable and their identification may avoid unnecessary delay in treatment planning. The current study serves as an atlas for the histology of extraneous material study and also as a reference for the pathologists whenever mystifying structures are encountered.

Quantification of inflammatory, angiogenic, and fibrous components of reactive oral lesions with an insight into the pathogenesis.

Background: Reactive oral lesions pose diagnostic difficulties as they mimic each other clinically. A definitive diagnosis is made based on the histopathological presentation of this group of lesion. Stromal microenvironment is the key to the sequence of the stages of these lesions. Stringent quantification of each component of the stroma is important to understand the pathogenesis. The aim is to evaluate inflammation, angiogenesis, and fibrosis in the reactive group of lesions through quantitative analysis. Materials and Methods: Blocks of irritation fibroma, inflammatory fibrous hyperplasia, pyogenic granuloma, and normal mucosa were retrieved from the archives and Hematoxylin and Eosin (H&E) and Masson Trichrome staining were done. The severity of inflammation, epithelial thickness, collagen proportionate area, integrated density of collagen, Mean Vascular Area (MVA), Mean Vascular Perimeter (MVP), and Mean blood vessel percentage area (MBVPA) were analysed quantitatively using Image J software version 1.8. The pattern of rete ridges at the epithelium-connective tissue interface was analysed qualitatively. Results: Inflammatory fibrous hyperplasia presented with severe inflammation (60%). Mean Vascular Percentage Area (MVPA) and Mean Vascular Perimeter (MVP) were increased in pyogenic granuloma. The mean collagen proportionate area and the integrated density of collagen were found to be more in irritation fibroma (64.47%, 2519638.01 ± 810471.58 µm2). The epithelial thickness was highest in inflammatory fibrous hyperplasia (62.71 ± 18.86 µm). Conclusion: Reactive oral lesions are histologically distinct, yet they exhibit considerable overlap depending on the stage of the lesion. A morphometric quantitative exploration of the individual pathogenic components may aid in specific diagnosis.

Decoding the link associated with areca nut chewing and cardiovascular disease using hsCRP as a biomarker.

Background: Chewing of areca nut is associated with various oral and systemic ill effects. The deleterious oral effects of areca nut have been widely documented to range from reactive lesions, periodontal health compromise to oral pre-cancer and cancerous states and have been described widely in the literature. The reported systemic effects of areca nut chewing are relatively less documented but reported in literature. Areca nut chewing may predispose to cardiovascular disease due to a systemic inflammatory response from the elevated levels of circulating inflammatory mediators. High-sensitivity C-reactive protein (hsCRP) is a systemic inflammatory biomarker to assess the risk of cardiovascular disease. Materials and Methods: This cross-sectional, observational study was conducted among areca nut chewers (n = 50) and non-chewers (n = 50). Areca nut chewers were considered as chewers/cases. Blood samples were collected from the participants and hsCRP levels were studied. The data were analysed using SPSS software, version 21 for statistical significance. Chi-square test was used to compare categorical variables. Mann-Whitney U test was done to analyse continuous variables. The level of statistical significance was set at P value < 0.05. Results: hsCRP mean was higher among the chewers (2.3 ± 3.7) compared to non-chewers (0.9 ± 1.3). The difference in hsCRP levels between the study group was statistically significant (P = 0.002). Conclusion: This study demonstrates the link between areca nut and cardiovascular disease using hsCRP as biomarker.

Evaluation of stress among dental undergraduates and postgraduates using salivary cortisol as a biomarker.

Background: Stress is a non-specific response of the body to any demand. Professional education has a certain level of stress inherent in it. Dental students have been reported in the literature to experience more stress than medical students. Objective: To evaluate the stress levels of dental students: first-year undergraduates, house surgeons, and final-year postgraduates, using salivary cortisol as a stress biomarker. Materials and Methods: Dental students above 18 years of age and without any systemic illness were included in the study. Those students with a drug history of corticosteroids, anti-depressants, and oral contraceptives were excluded from the study. Female participants experiencing pre-menstrual symptoms, pregnancy, and familial stressor issues were excluded from the study. First-year undergraduates, house surgeons, and final-year postgraduates were enrolled in the study. Unstimulated whole saliva was collected in the morning and evening between 9:00 and 10:00 am and between 3:00 and 4:00 pm. Salivary cortisol levels were assessed by chemiluminescence immuno-assay (CLIA). Results: Paired sample t-test was used to compare the diurnal variation among morning and afternoon samples within the groups. The salivary cortisol levels were found to be significant within the groups. One-way ANOVA was used to compare the salivary cortisol levels between the groups. The salivary cortisol levels within the groups were not statistically significant. Conclusion: Salivary cortisol is a non-invasive biomarker of stress. Postgraduates had higher salivary cortisol levels than other study groups.

Secretory carcinoma of salivary gland - A systematic review of pediatric case reports and case series.

AIM: Mammary analog secretory carcinoma (MASC) is a new pathological entity of salivary gland origin recognized as Secretory Carcinoma (SC) in the WHO 2017 classification. Pediatric cases of MASC were reviewed systematically from 2010 to 2019. MATERIALS AND METHODS: Databases were searched from 2010 to 2019 for pediatric case reports and case series, excluding retrospective studies. A total of 12 manuscripts were reviewed for clinical, histological and immunohistochemical findings. RESULTS: A total of 13 pediatric cases (11 case reports and 1 case series of 2 cases) of MASC in pediatric patients were found. The youngest reported age was 5 years. The common site was parotid gland usually presenting as a slowly growing firm, painless mass. CONCLUSION: MASC should be considered in the differential diagnosis of salivary gland tumors in pediatric population, especially from parotid gland. Extended research on such recent entities with more inputs from new cases reported in literature may outstretch the possibilities of therapeutic fusion inhibition in future.

New Insights for Consummate Diagnosis and Management of Oral Submucous Fibrosis Using Reactive and Reparative Fibrotic Parameter Derived Algorithm.

OBJECTIVE: Reproducibility of qualitative changes in histopathological diagnosis involving narrow variation is often challenging. This study aims to characterize the histological fibrotic events in detail so as to derive an in-depth multiparametric algorithm with individually quantified histological parameters for effective monitoring of the. disease process in oral submucous fibrosis and for potential therapeutic targets for early intervention. METHODS: Formalin fixed paraffin embedded (FFPE) blocks of oral submucous fibrosis (OSMF), were taken and sections were stained with Hematoxylin & Eosin stain and Masson Trichrome stain. Photomicrographs were assessed for various morphometric parameters with Image J software version 1.8. Linear Regression was used to model the relationship using Inflammatory Cell Count, Extent of Inflammation collagen stained area, Epithelial thickness integrated density of collagen, MVPA, Area, Perimeter, were taken as variables. RESULT: Inflammatory cell count and the extent of inflammation also decreased with increasing grades of OSMF. Collagen proportionate area, integrated collagen density and epithelial thickness were compared among different grades of OSMF. Grade IV OSMF had greatest mean collagen proportionate area , highest integrated collagen density and lowest epithelial thickness when compared to other grades of OSMF. Linear regression model revealed smaller variation between Grade I to Grade II. Whereas Grade II to Grade IV exhibited larger variation suggestive of increased growth rate and all the coefficients were found to lie within 95% confidence limits. CONCLUSION: Diagnostic algorithm with multiparametric regression model were derived and combinatorial therapeutic approaches have been suggested for more effective management of oral submucous fibrosis.

COVID-19: Implications on dental profession and precautionary guidelines.

The current global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated coronavirus disease (COVID-19), has grasped the attention of entire international community and has caused widespread public health concerns. All the efforts taken globally to curtail the novel COVID-19; the outbreak is still on a rise owing to the community spread pattern of this infection. COVID-19 is a zoonotic infection that, like other coronavirus infections, is believed to have been originated in bats and pangolins, and later transmitted to humans. Once in the human body, this coronavirus (SARS-CoV-2) is abundantly present in nasopharyngeal and salivary secretions of affected patients and its spread is predominantly thought to be respiratory droplet in nature. Dental professionals may soon encounter patients with suspected or confirmed SARS-CoV-2 infection and will have to act carefully not only to provide care but at the same time prevent spread of infection. Thus, the aim of this article is to provide a brief overview of the epidemiology, symptoms and routes of spread of the novel COVID-19 infection. In addition to this, specific recommendations for dental practice are prescribed for patient screening, infection control strategies, and patient management protocol.

Use of rat jejunum for assay of acetylcholine.

Experiments were carried out to determine the advantage in using isolated rat jejunum in the assay of acetylcholine (ACh) in preference to other tissues. Rat jejunum was found to be sensitive to ACh 0.01 micrograms, 5-hydroxytryptamine (5HT) 0.2 to 0.5 microgram and least sensitive to histamine. (Ach greater than 5HT greater than histamine).

Microbial flora in gut of Culex quinquefasciatus breeding in cess pits.

The number and types of microorganisms in the gut of Culex quinquefasciatus larvae varied considerably from one site of collection to another. Larval gut, in general, contained enormous number of bacteria, a few fungi and negligible number of actinomycetes which belonged to 15 bacterial, 6 fungal and 4 actinomycete genera, respectively. Bacillus sp., Staphylococcus sp. and Pseudomonas sp. among bacteria, Aspergillus among fungi and Streptomyces sp. among actinomycetes were frequently encountered. Escherichia, Proteus, Aspergillus and Streptomyces were the most abundant genera. Isolates of Bacillus, Pseudomonas, Shigella and Staphylococcus caused 100% mortality during the early instar of larval development. None of the fungal isolates effected 100% mortality while Nocardiopsis sp. among actinomycetes gave 100% mortality. One of the Escherichia isolate suppressed the adult emergence completely while 27 others, belonging to most of the genera found, suppressed significantly. Isolates of Aspergillus, Alternaria and Streptomyces inhibited the emergence of adults completely.