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Context: Hematoxylin-eosin (H&E) stain has stood the test of time as the standard stain for histologic examination of human tissues. Haematoxylin is a natural dye, on the contrary, its counterstain eosin is a synthetic dye which belongs to the xanthene group. Synthetic dyes are hazardous to human and animal health. With the increasing awareness of a green earth, it is advisable to use environment-friendly and biodegradable materials. Therefore, an attempt was made to develop as biofriendly substitute in the form of food colour as a counterstain for haematoxylin. Aim: To assess the staining ability of food colouring agents in routine staining and to compare its staining efficacy with Eosin. Settings and Design: Two food colours were obtained and stain was prepared by using 70% ethyl alcohol as counterstain for haematoxylin. Different tissue structures such as epithelium, keratin, collagen fibers, muscles, salivary glands, adipocytes, blood vessels, RBCs were observed and evaluated. Methods and Material: Group A -10 slides stained with green food colour, Group B - 10 slides stained with tomato red food colour and Group C - 10 slides stained with conventional H and E. The stained sections were assessed and graded for nuclear staining, cytoplasmic staining, clarity, uniformity and crispness of staining. Statistical Analysis Used: The non-parametric Kruskal-Wallis and Mann-Whitney U tests were performed for statistical analysis. Results: There was no statistically significant difference between the three study groups with respect to all the parameters except crispness of staining. The crispness of Tomato Red and H and E was better compared to green food colour. Conclusions: Food colouring agents can be used as a safe, biofriendly and inexpensive substitute to eosin in conventional soft tissue staining.
RESUMO
OBJECTIVES: Platelet-rich fibrin (PRF) procuring protocols have been suggested, differing in speed and time duration. Since different derivation protocols may alter PRF characteristics, the present study was conducted to evaluate the variations in the fibrin network pattern, platelet count, and antimicrobial efficacy of PRF procured using variable centrifugation speeds and time durations in different age groups. MATERIALS AND METHODS: Sixty healthy subjects participated in the study and were equally divided into three age groups (20-34 years, 35-49 years, 50-65 years). From each age group, total of 6 PRF membranes were fabricated from 10 ml tubes. Three PRF membranes were obtained at 1400, 2800, and 3500 rpm for 8 min while other 3 membranes were obtained after 15 min of centrifugation respectively. The relative centrifugal force (RCF) values were within the spectrum of 228-1425 g. PRF membranes were then subjected to platelet count estimation, antimicrobial activity against oral bacteria, and changes in fibrin network pattern with respect to different age groups and different centrifugation protocols. RESULTS: Highest platelet concentration, antimicrobial activity, and dense fibrin network were obtained in 20-34 years age group. Intragroup analysis within each group revealed highest platelet count and antimicrobial activity in PRF membranes, obtained at 1400 rpm for 8 min. Denser fibrin network pattern was demonstrated by PRF membranes procured at 3500 rpm for 15 min. CONCLUSIONS: PRF properties, i.e., platelet count, antimicrobial efficacy, and fibrin network, are influenced by technical aspects of PRF preparation (RCF value, centrifugation speed, and time) and patient age. CLINICAL RELEVANCE: Based on the finding of present study, it can be implied that lower centrifugation speed and time can increase the platelet concentration and antimicrobial activity of the PRF membrane. Contrarily, lowering the speed and time leads to lesser density fibrin network pattern. Centrifugation protocols thus need to be adapted accordingly.
