Search

Renal cell carcinoma (RCC) accounts for 85% of all primary renal cancers. The definitive diagnosis of RCC relies exclusively on the subjective pathological interpretation of the surgical specimen. In this study, we aimed to analyze renal tissue using objective Raman spectroscopy (RS). We obtained 15 pairs of RCC (T) and corresponding normal renal parenchymal tissues (N) from our biobank. There are three subtypes of RCC: clear cell RCC (ccRCC), papillary RCC (pRCC), and chromophobe RCC (cRCC). Five pairs of tissue of each subtype were enrolled. Fresh-frozen sliced tissues were used for the RS detection. The Raman spectra between T and N were compared and analyzed using partial least squares (PLS) regression. Data for a total of 55 T and 58 N analyzable RS samples were obtained. The spectra were normalized by dividing the intensity of the characteristic peak at 1003 cm−1 using phenylalanine's Raman peak. After further analysis with PLS, the sensitivity and specificity for discriminating T from N were 95% and 93%, respectively. The RCC subtypes can be discriminated at an accuracy of 72% for ccRCC, 88% for cRCC, and 86% for pRCC. This study demonstrates the feasibility of analyzing renal tissue using RS. RS, with its advantages of easy and objective tissue assessment, may be applied to aid intraoperative decision making and pathological tissue assessment. Copyright © 2014 John Wiley & Sons, Ltd.

In this study, a portable Y-type fibreoptic fluorescence spectroscopy measurement system was used to evaluate the freshness of eight cobias (Rachycentron canadum). The results showed that the ratio of fluorescent intensity, which F480 nm/Fexci+50 nm was belong with the range of collagen type I and type V characteristic spectra, was positive correlated to the frozen time by hours. It was a strong approach to be a potential index for differentiating the fish freshness during delivery process. Besides, the different pattern results of dorsum and abdomen were shown in this study. In further, fibreoptic fluorescence spectroscopy could be a way not only to measure and quantify the freshness of different fish body but also to verify the level of taste.

Recent studies have demonstrated that the autofluorescence technique is a very promising tool for early-stage cancer diagnosis in various tissues. Many researchers have applied the autofluorescence technique through fiber-optic cables to excite tissues and collect the fluorescent emission signal from the tissues for discrimination analysis. In this study, we developed a Monte Carlo–light-induced autofluorescence (MCS LIAF) simulation model to optimize the oblique angle in the excitation optical fiber and the spatial arrangements in the receiving optical fiber. Our aim was to discriminate cervical tissues at different dysplastic stages. The model combined the structure of multi-layered tissues, tissue optical scattering and absorption parameters, tissue fluorophore concentration, the characteristic fluorescent spectrum of fluorophores, and the excitation and receiving arrangement of the optical fibers. The results show that the optimal oblique angle of the excitation optical fiber is between 0° and 45° and that the optimal receiving optical fiber is positioned 200 μm away from the origin. We also observed that changing the excitation angle is very useful in differentiating normal from cervical intraepithelial neoplasia (CIN) I or CIN II tissues. Also, using the fluorescence peak ratio of NADH/collagen can help discriminate CIN III from normal tissues and CIN I/II tissues.

The mechanical properties of trachea can reflect the bio-function and may represent the changes of compliances and stifinesses of airway. Therefore, the difference of airway mechanical properties between the normal people and the patients with airway disease can be observed in clinic. The objective of this paper is to determine the trachea elasticity of normal people by non-invasive ultrasound imaging method in statistic pressure. The measurement was involved 9 normal subjects (age from 23 to 40, 4 males and 5 females) and 2 patients (age from 23 to 40, 2 males). A Threshold Positive Expiratory Pressure device (Threshold PEP, New Jersey, USA) was used to provide positive expiratory pressure therapy. All subjects were asked to breathe through a mouthpiece. Then, 5 different loads of PEP were applied to the range from 0 cmH2O to 20 cmH2O and in a scale of 5 cmH20. A clinical ultrasound system ( Terason 2000 Burlington, MA, USA) with a 7 MHz transducer for measuring the mean diameter of trachea anteroposterior and transverse from thyroid cartilage and suprosternal notch. Finally, the ultrasound imaging was captured and analyzed by calculating the elasticity, Young's Modulus, which was taking the ratio of stress over strain. The Intra-class correlation coefficients were employed to verify the reliablity for the experiment. Our result shows that the elasticity of normal subject tracheal were in the range of 145~981kPa, the abnormal subject were in the range of 69~108kPa, and the Intra-class correlation coefficients were in the range 0.8~0.99. In this study, we demonstrate the use of ultrasound imaging for measuring airway mechanical property and we also observed significant difference of the stress to strain experiments between normal subject and abnormal subject. This paper provides a new approach to measure the elasticity of human tracheal in real time, patient-friendly way.

Raman spectroscopy was applied to distinguish the spectroscopic information between normal cervical tissues (14) and cervical neoplasia (17), including low grade squamous intraepithelial lesions (6) and high grade squamous intraepithelial lesions (11). Standard pathological sections of these cervical tissues were measured from superficial to stroma layers. We have normalized significant Raman peaks, 1250 and 1579-1656 cm -1 by taking a ratio over a stationary Raman at 1004 cm -1 , and successfully discriminated between normal and neoplasm cervical tissues.

Monte Carlo fluorescence model has been developed to estimate the autofluorescent spectra associated with the progression of the Exo-Cervical Intraepithelial Neoplasm (CIN). We used double integrating spheres system and a tunable light source system, 380 to 600 nm, to measure the reflection and transmission spectra of a 50 μm thick tissue, and used Inverse Adding-Doubling (IAD) method to estimate the absorption (μa) and scattering (μs) coefficients. Human cervical tissue samples were sliced vertically (longitudinal) by the frozen section method. The results show that the absorption and scattering coefficients of cervical neoplasia are 2~3 times higher than normal tissues. We applied Monte Carlo method to estimate photon distribution and fluorescence emission in the tissue. By combining the intrinsic fluorescence information (collagen, NADH, and FAD), the anatomical information of the epithelium, CIN, stroma layers, and the fluorescence escape function, the autofluorescence spectra of CIN at different development stages were obtained.We have observed that the progression of the CIN results in gradually decreasing of the autofluorescence intensity of collagen peak intensity. In addition, the existence of the CIN layer formeda barrier that blocks the autofluorescence escaping from the stroma layer due to the strong extinction(scattering and absorption) of the CIN layer. To our knowledge, this is the first study measuring the CIN optical properties in the visible range; it also successfully demonstrates the fluorescence model forestimating autofluorescence spectra of cervical tissue associated with the progression of the CIN tissue;this model is very important in assisting the CIN diagnosis and treatment in clinical medicine.

Monte Carlo modeling was developed for simulating the light induced autofluorescence spectra of colon and cervical tissues at different dysplasia grades.These tissues were frozen sliced into 100 um thickness. The transmittance (Ta) and backscatter spectra (Ra) of these tissues were measured using double integral sphere system. The scattering coefficient, μs, and absorption coefficient, μa, were determined by the inverse adding-doubling (IAD) method from the Ta and Ra. spectra. The fluorescence intensity and spectra of these sliced tissues were measured using spectrometer system with cooled 2D CCD array. We simulated light energy distribution in tissue at 330 nm excitation and then convolution with fluorophores intensity and escape function in each tissue layer. The results of the simulation show: (1)fluorescence spectra change with different tissue characteristics, (2)fluorescence intensity decrease with the development of the dyplasia grades and the mucosa thickness, (3)the relative collagen signal decreases, hemoglobin signal increases, and NADH signal increases along with the dyplasia development. The simulated results matched well in vivo measured results. The approach provides an important means for understanding tissue fluorescence spectra’s changes that are very critical for clinic diagnosis.

We present autofluorescence modeling of different cervix tissue dysplasia for clinical diagnosis. We used double integrating sphere system and inverse adding-doubling (IAD) method to evaluate tissue optical parameters (absorption coefficient, /spl mu//sub a/, scattering coefficient, /spl mu//sub s/) of different cervix dysplasia. We used fluorescence Monte Carlo model included absorption coefficient and scattering coefficient from IAD and integrate sphere, to simulate autofluorescence spectra. The results show the increasing thickness of abnormal tissue on the cervical epithelium accompanied with the decreasing in autofluorescence intensity, in collagen peak (390 nm) and in NADH peak (460 nm), along with the lesion developments.

This paper is deals with the implementation of autofluorescent excitation-emission matrices for the differentiation of cervical tissue. Autofluorescence diagnosis is characterized by the stimulation of endogenous fluorophores, such as, collage, NADH, and FAD in normal and abnormal tissue. !t has minimum invasion and it is in real time. In this research, we developed a small autofluorescence spectra measurement system. It consists of a sensitive PMT with a double gratings spectrometer, a Y type fiber including 18-excitation to 19-emission fibers, and xenon lamp with monochromate as multi-wavelength light source. We utilized this autofluorescence spectra and excitation-emission matrices (EEM) in cervical cancer study and measured normal and abnormal tissues (cervical intraepithelial neoplasia, CIN squamous cell carcinoma: SCC). EEM represented multi-excited wavelengths induced by different range wavelength of the emission. It allows us to get more information about tissues' characteristic. We used partial least squares (PLS) to analyze these data of the spectra and EEM. The result shows that the diagnostic ability by autofluorescence technology can be applied to ClN and using PLS analyzed pathological changes of the cervical tissue has a discriminative property. We also got high sensitivity and specificity to distinguish between normal endo and exo cervix by combining EEM and PLS . In the future, we will build autofluorescence EEM database for clinic diagnosis information.