Bacillus velezensis (strains A6 & P42) as a potential biocontrol agent against Klebsiella variicola, a new causal agent of soft rot disease in carrot.

Bacterial soft rot is one of the most devastating diseases and a major constraint encountered during carrot farming. Biological agents are the best eco-friendly alternatives to agrochemicals to manage soft rot disease to ensure environmental sustainability. In this study, about eight isolates of bacterial pathogen causing soft rot in carrots were collected from Karnataka, India. Based on the 16S rRNA sequencing the pathogen isolates causing soft rot of carrot were identified as Klebsiella variicola. The morphological characteristics of K. variicola was investigated under scanning electron microscopy. The pathogenicity assay showed that all eight isolates were pathogenic to the carrot. An in vitro and in planta assay of two novel strains of Bacillus velezensis (A6 and P42) against K. variicola indicated that both strains had strong antagonistic activity against all the pathogen strains. Furthermore, the volatile bioactive compounds produced by A6 and P42 strains were analyzed in GC-MS, which revealed the presence of 10 and 6 bioactive compounds in their culture filtrate, respectively, with antibacterial and antifungal properties. The present study suggests that both A6 and P42 strains of B. velezensis were antagonistic to K. variicola and can be used as biocontrol agents to manage soft rot diseases of carrot under field conditions.

Cd34 and Mast Cell Analysis in Normal Oral Mucosa and Different Grades of Oral Squamous Cell Carcinoma: A Comparative Study.

BACKGROUND: Oral Squamous Cell Carcinoma (OSCC) remains a serious health problem worldwide. Prognosis of OSCC is poor and long term survival rate still remains below 50%. Angiogenesis or neovascularisation plays an important role in tumour progression and metastasis. Mast cells have been implicated in promoting tumour angiogenesis, especially of digestive tract, little is known in OSCC. AIM & OBJECTIVE: To study the correlation between blood vessel density (BVD) and mast cell density (MCD) in different grades of OSCC. METHODS: Thirty eight paraffin blocks of different grades of OSCC were retrieved from the department and sections were stained with CD34 followed by counterstaining with toluidine blue. The slides were then analysed using Leica Software (Version 4.5). RESULTS: Mean BVD and MCD were found to be increased in OSCC as compared to normal mucosa. Increase in BVD with co-current increase in MCD was also observed in different grades of OSCC. CONCLUSION: From our study, it was concluded that, mast cells play a major role in promoting tumour angiogenesis. But, as the grade of the tumour increases, other angiogenic factors may play a more significant role than mast cells in tumour progression.

Keratoameloblastoma a rare entity: a case report.

Ameloblastoma is the second most common odontogenic tumour of oral cavity; which has several different histological variants such as follicular, plexiform, acanthomatous, granular cell, desmoplastic, basal cell, clear cell, hemangiomatous, mucous cell differentiation and keratoameloblastoma. It is common in posterior mandible and has high male predilection in the ratio of 3:1. This report presents a case of keratoameloblastoma in 65-year-old female patient in the anterior mandible region with literature review on clinical features, histopathological findings, radiological appearance and treatment options.