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Plant mediated synthesis of metal nanoparticles (MNPs) has been considered as a reliable green technique for mitigating the involvement of toxic chemicals and which is widely used for desired applications. In the present study, a simple and environment friendly approach for the synthesis of silver nanoparticles (AgNPs) using the aqueous extract of Cynodon dactylon was proposed. The phytochemicals present in C. dactylon acted as the reducing as well as the capping agents during the nanoparticle synthesis. The aqueous extract of C. dactylon added to AgNO3 solution showed a colour change from brown to black at room temperature which confirmed the formation of AgNPs. UV-Vis spectral analysis revealed the surface plasmon resonance band of synthesised AgNPs at around 380 nm, while FT-IR spectroscopy confirmed the role of biomolecules present in the plant extract in the reduction and efficient stabilisation of AgNPs. The X-ray diffraction (XRD) patterns confirmed distinctive peaks corresponding to the crystalline planes of cubic silver. Shape and surface morphology of green AgNPs were examined by SEM. Biosynthesized AgNPs were predominantly cubical and spherical with an average particle size of 30.5 nm approximately as observed through SEM and DLS analysis respectively. The EDS analysis displayed intense signals of silver element. The stability of AgNPs was confirmed by zeta potential analysis. A negative zeta potential value of -17.1 mV indicated the stability and good dispersion of AgNPs. Antimicrobial and anti-inflammatory potentials of green synthesised AgNPs were analysed through in vitro techniques. The cytotoxic effect of green AgNPs on normal fibroblast cells (L929) was studied to analyse its effect on normal cells.
RESUMO
BACKGROUND: Argyrophilic nucleolar organizer regions (AgNORs) is demonstrated to be useful in diagnostic pathology, mainly to distinguish benign lesions from their malignant counterparts. We aimed to correlate AgNORs pleomorphism with the severity of lesion in oral submucous fibrosis (OSMF) and oral squamous cell carcinoma (OSCC) using a retrospective study on 45 archival tissues. MATERIALS AND METHODS: Silver nitrate staining was performed on archival tissues consisting of 20 OSMF and 20 OSCC. Five biopsies from normal oral mucosa acted as a control. One hundred cells per slide were observed for AgNORs dots, which were classified as typical (spherical) and atypical (large, kidney-shaped and clustered). RESULTS: A positive and significant correlation was found between increased atypical shapes and increasing grades of OSMF and OSCC. CONCLUSIONS: AgNORs pleomorphism can be a reliable criterion to assess disease severity and progression in OSMF and OSCC.
RESUMO
BACKGROUND: Vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) have been implicated in the pathogenesis of cysts. Both these factors seem to be interrelated to each other. The importance of the MMPs in the induction of the angiogenic process has recently been described. MMPs, which are produced by microvascular endothelial cells, break down the extracellular matrix. This is one of the earliest and sustained events in the process of new capillary formation. Thus, we studied the expression of VEGF and MMP-9 in Keratocystic odontogenic tumors (KCOTs), dentigerous cysts (DCs) and radicular cysts (RCs). MATERIALS AND METHODS: Ten cases each of KCOTs, DCs and RCs and were included in the study and immunohistochemistry was performed using anti-VEGF and anti-MMP-9 antibody using standard protocol. RESULT: When the data of positive cells in the epithelium of KCOTs was compared with DCs and RCs, it showed highly significant results (P<0.05). Furthermore, the expression of VEGF and MMP-9 in the stroma of KCOTs showed a significant result when compared to DCs and RCs. The expression of VEGF in inflammatory cells was more in RCs when compared to DCs. Also, the expression of MMP-9 was more in RCs and DCs as compared to KCOTs. CONCLUSION: Higher expression of VEGF and MMP-9 in KCOTs could be responsible for the aggressive behavior of this cyst that is currently considered a cystic tumor rather than a developmental cyst.
