Antidepressant & anxiolytic activities of N-(pyridin-3-yl) quinoxalin-2-carboxamide: A novel serotonin type 3 receptor antagonist in behavioural animal models.

BACKGROUND & OBJECTIVES: Alteration in the serotonin leads to the psychological illness, such as depression, anxiety, schizophrenia, eating disorders, obsessive-compulsive disorder, panic disorders and migraines. The objective of the current study was to investigate the antidepressant and anxiolytic activities of N-(pyridin-3-yl) quinoxalin-2-carboxamide (QCF-21), a novel 5-HT3receptor antagonist in preclinical models of depression and anxiety. METHODS: Antidepressant activity was evaluated in preliminary tests such as forced swim and tail suspension tests (FST & TST). Anti-anxiety effect of QCF-21 was investigated by employing elevated plus maze (EPM), light/dark and hole board tests. Olfactory bulbectomy (OBX) in rats was used as chronic model of depression. Mechanistic test of QCF-21 was evaluated by reserpine-induced hypothermia and 5-hydroxytryptophan (5-HTP)-induced head-twitch response. RESULTS: The dose-response study revealed an initial antidepressant-like effect of QCF-21(0.25-1 mg/kg, i.p.) in the FST and TST and anxiolytic-like effect in EPM, light and dark and hole board tests. QCF-21 potentiated the 5-HTP-induced head-twitches response in mice and reversed reserpine-induced hypothermia in rats. QCF-21 significantly reversed the behavioural anomalies post-OBX in rats. INTERPRETATION & CONCLUSIONS: The present findings indicate the potential antidepressant-like and anxiolytic-like effects of QCF-21 at low doses in rodent behavioural models of depression and anxiety. Further studies need to be done to understand the underlying mechanism.

Comparative Study of Clinical Staging of Oral Submucous Fibrosis with Qualitative Analysis of Collagen Fibers Under Polarized Microscopy.

BACKGROUND & OBJECTIVES: Oral submucous fibrosis (OSMF) is a condition where excessive deposition of dense collagen fibers occurred in the connective tissue of oral mucosa. An alteration of collagen necessitates an in depth understanding of collagen in oral tissues as no breakthrough studies have been reported. T herefore the aim was to correlate the clinical, functional and histopathological staging and to analyze the polarization colors and thickness of the collagen fibers in different stages of OSMF using picrosirius red stain under polarizing microscopy so as to assess the severity of disease. METHODS: The study was conducted in the department of Oral Pathology and Microbiology at Padm. Dr. D. Y Patil Dental and Hospital, Navi Mumbai, India (2012-13). A sample size was of a total 40 subjects, of which 30 patients had OSMF, and 10 were in control group. Clinical, functional and histopathological staging were done depending upon definite criteria. Collagen fibers were analyzed for polarizing colors and thickness. Further clinical, functional and histopathological stages as well as qualitative parameters of collagen fibers were compared. RESULTS: The correlation between clinical and functional staging was not significant ( P >0.05) whereas the comparison of the functional staging with histopathological staging was more reliable ( P <0.01) as an indication to the severity of the disease rather than clinical staging. One-way ANOVA analysis showed highly significant correlation between functional staging and polarization colors and thickness of collagen fibers ( P <0.001). CONCLUSION: The qualitative change in the collagen fibers of OSMF patients using polarized microscopy would help to assess its role in diagnostic evaluation, to determine the prognosis of the disease as well as to provide useful predictive treatment modalities to them.

Intraosseous malignant peripheral nerve sheath tumor of maxilla: A case report with review of the literature.

Malignant peripheral nerve sheath tumor (MPNST), the principle malignancy of peripheral nerve origin, though rare in the general population, occurs with excessive frequency among patients with neurofibromatosis. This tumor always arises in soft-tissues, usually found in the lower extremities and only 10-12% of all lesions occur in the head and neck region, which makes it a rare entity. The primary intraosseous MPNST is rare and has been reported most frequently in the mandible. This article discusses a case report of MPNST of the left maxilla without a history of benign nerve tissue tumor and the diagnostic difficulties associated with MPNST.

Primary intraosseous squamous cell carcinoma arising from an odontogenic keratocyst: a case report and literature review.

Primary intraosseous squamous cell carcinoma (PIOSCC) derived from an odontogenic keratocyst (OKC) is a rare malignant neoplasm of the jaws, which is locally aggressive with quite poor prognosis. The incidence of carcinomas arising in odontogenic cysts was reported to be approximately 1-2/1000. The number of well-documented cases of PIOSCC ex OKC is extremely small; hence, no sufficient incidence data are available in the literature. Overall, the survival rate of an individual, which is a period of two years, is very poor, and this can be attributed to the delayed diagnosis. But knowledge of the histopathological and immunohistological features of PIOSCC allows accurate and early diagnosis of the lesion so that an early and appropriate treatment can be instituted for better prognosis. The following report describes an extremely rare case of PIOSCC of the mandible derived from an OKC in a 20-year-old female patient.