Laser‐induced autofluorescence spectral ratio reference standard for early discrimination of oral cancer

Abstract

This study investigates the scaling of photobioreactor productivity based on the growth of Nannochloropsis salina incorporating the effects of direct and diffuse light. The scaling and optimization of photobioreactor geometry was analyzed by determining the growth response of a small‐scale system designed to represent a core sample of a large‐scale photobioreactor. The small‐scale test apparatus was operated at a variety of light intensities on a batch time scale to generate a photosynthetic irradiance (PI) growth dataset, ultimately used to inform a PI growth model. The validation of the scalability of the PI growth model to predict productivity in large‐scale systems was done by comparison with experimental growth data collected from two geometrically different large‐scale photobioreactors operated at a variety of light intensities. For direct comparison, the small‐scale and large‐scale experimental systems presented were operated similarly and in such a way to incorporate cultivation relevant time scales, light intensities, mixing, and nutrient loads. Validation of the scalability of the PI growth model enables the critical evaluation of different photobioreactor geometries and design optimization incorporating growth effects from diffuse and direct light. Discussion focuses on the application of the PI growth model to assess the effect of diffuse light growth compared to direct light growth for the evaluation of photobioreactors followed by the use of the model for photobioreactor geometry optimization on the metric of areal productivity. Biotechnol. Bioeng. 2012; 109:363–370. © 2011 Wiley Periodicals, Inc.

Comparative evaluation of the diagnostic performance of autofluorescence and diffuse reflectance in oral cancer detection: a clinical study

“…This peak has been reported as due to emission from endogenous fluorophores like NADH, FAD, collagen, elastin and amino acids, while the 635 and 705 nm peaks are from enhanced occurrence of PpIX in malignant tissues. The additional peak seen at 685 nm in SCC and dysplastic lesions could be due to the accumulation of corproporphyrin III, a constituent of the heme synthesis pathway in malignant tissues [14]. The DR spectra from normal, hyperplastic, dysplastic and SCC lesions showed significant dips around 545 and 575 nm (Figures 2b, 3b and 4b).…”

“…Lesions from the buccal mucosa, palate, ventral tongue and floor of the mouth were included in this study while those on the dorsal/lateral sides of the tongue and the vermilion border of the lip were excluded as bacteria present in these sites emit fluorescence at 635 nm that interferes with the protoporphyrin IX fluorescence [14,15]. Before measurements, all patients and healthy volunteers were asked to rinse their mouth with 0.9% saline solution for two minutes in order to reduce the effect of recently consumed food.…”

Precipitants of 5-Fluorouracil in Trabeculectomy Bleb Management: A Comparative Laboratory Study

“…These new imaging techniques yield promising results in oral cavity, with sensitivity 91.3% and specificity 100%. 32 Narrow band spectrum optical filters used to enhance visualization of mucosal pattern are used in narrow band imaging. 33 Further research is necessary to understand the diagnostic value of these technologies.…”

Diagnostic Aids in Oral Cancer Screening

“…These techniques has been used in oral cavity and a SN=91.3% and SP=100% have been reported (Mallia et al 2008). Narrow band imaging is a novel technique which uses narrow-band spectrum optical filters to enhance the visualization of mucosal and sub-mucosal microvascular patterns.…”