ChiCTR-IOC-16007882.

A confocal fluorescence spectroscopy system is instrumented to study depth-resolved autofluorescence in biological tissue. The system provides the capability of optical sectioning with the maximal detectiondepth up to 120 m in the examined tissue samples. It was found that the topmost keratinizing epithelial layer produces strong fluorescence similar to collagen. The fluorescence signal from epithelial tissue between the keratinizing layer and stroma can be well resolved. The study results show that depth-resolved fluorescence spectroscopy has the potential to provide more accurate information for the diagnosis of tissue pathology.

No abstract

A portable confocal system with the excitations at 355nm and 457nm was instrumented to investigate the depth-resolved fluorescence of cervical tissue. The study focused on extracting biochemical and morphological information carried in the depth-resolved signals measured from the normal squamous epithelial tissue and squamous intraepithelial lesions. Strong keratin fluorescence with the spectral characteristics similar to collagen were observed from the topmost keratinizing layer of all tissue samples. It was found that NADH and FAD fluorescence measured from the underlying non-keratinizing epithelial layer were strongly correlated to the tissue pathology. This study demonstrates that the depth-resolved fluorescence spectroscopy can potentially provide more accurate diagnostic information for determining tissue pathology.

This study identified the age-specific prevalence and epidemiologic risk profile for infection with different groups and species of human papillomaviruses (HPV). Structured interview and HPV testing were conducted for 2,604 Chinese women self-referred for cervical screening. Independent risk factors for infection were identified by multiple logistic regressions. Overall, a major peak of HPV infection was observed at women aged 26-30 years, and a minor peak at 46-55 years. This pattern was observed for high-risk, low-risk, and alpha-5/7/9 HPVs; but alpha-3/6 HPVs showed peaks of similar magnitudes in young and older women. Independent risk factors for HPV infection (all types combined) included younger age (OR [95% CI] for >55 vs. < or =30 years = 0.22 [0.09-0.55]; 31-45 vs. < or = 30 years = 0.57 [0.33-0.99]), having > or =4 lifetime sexual partners (2.28 [1.06-4.88]), and smoking (2.24 [1.22-4.10]). Young age and smoking were the most consistent independent risk factors observed across different HPV groups. The risk profile for high-risk HPV was similar to alpha-5/7/9. Single-type infection was associated with having more sexual partners, higher education level and oral contraception; whereas multiple-type infection was associated with smoking. In conclusion, a U-shaped age-specific prevalence curve was observed for HPV infection overall, but with a different pattern for different HPV species. Different HPV groups showed variations in their risk profiles. These data are useful for formulating preventative strategy for HPV-related diseases. Catch-up vaccination program in Hong Kong should cover a wider age group as the first peak of infection occurred relatively late.