Background Fluorescence spectroscopy is an evolving technology that can rapidly differentiate between benign and malignant tissues. These
differences are thought to be due to endogenous fluorophores, including nicotinamide adenine dinucleotide, flavin adenine
dinucleotide, and tryptophan, and absorbers such as β-carotene and hemoglobin. We hypothesized that a statistically significant
difference would be demonstrated between benign and malignant breast tissues on the basis of their unique fluorescence and
reflectance properties.
Methods Optical measurements were performed on 56 samples of tumor or benign breast tissue. Autofluorescence spectra were measured
at excitation wavelengths ranging from 300 to 460 nm, and diffuse reflectance was measured between 300 and 600 nm. Principal
component analysis to dimensionally reduce the spectral data and a Wilcoxon ranked sum test were used to determine which wavelengths
showed statistically significant differences. A support vector machine algorithm compared classification results with the
histological diagnosis (gold standard).
Results Several excitation wavelengths and diffuse reflectance spectra showed significant differences between tumor and benign tissues.
By using the support vector machine algorithm to incorporate relevant spectral differences, a sensitivity of 70.0% and specifcity
of 91.7% were achieved.
Conclusions A statistically significant difference was demonstrated in the diffuse reflectance and fluorescence emission spectra of benign
and malignant breast tissue. These differences could be exploited in the development of adjuncts to diagnostic and surgical
procedures. 相似文献
Two Schistosomajaponicum vaccine candidate antigens Sj 31 and Sj 32, which have shown particular promise to induce protective immunity in mice, were used to immunize goats by using a DNA priming-protein boosting strategy in present work. DNA vaccine formulations of the two antigens （VRSj31 and VRSj32） were produced and injected intramuscularly twice at a 2-week interval and then recombinant proteins （rSj31 and rSj32） together with Freund Complete Adjuvant （FCA） were used to boost the goats. The experiment was repeated in different batche cercariae. A strong anamnestic antibody response was induced after boost. A significant reduction of liver egg counts and miracidial hatching was showed in both experiments. Significant protections against challenge infection were elicited with 31.6% of percentage reduction for worm recovery in the second experiment and 20.9% in the first experiment, respectively. 相似文献
Summary: A novel copolymer containing perylene bisimide and porphyrin units was synthesized through a Wittig‐type coupling reaction and characterized. An electrochemical experiment showed its electronic properties. Optoelectronic measurements showed a steady and rapid cathodic photocurrent response of the polymer film. The features of copolymer colloids were also studied by UV‐Vis spectrometry and TEM. A large quantity of nanoparticles were observed with TEM, with a mean diameter of 200 nm. The size effect leads the absorption wavelength of the nanoparticles to be red‐shifted, which is consistent with the results of UV‐Vis spectrometry.
