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A random rayburst sampling (RRBS) framework was developed to detect the nucleus and cell membrane boundaries in three-dimensional (3-D) space. Raw images were acquired through a full-field optical coherence tomography system with submicron resolution--i.e., 0.8 µm in lateral and 0.9 µm in axial directions. The near-isometric resolution enables 3-D segmentation of a nucleus and cell membrane for determining the volumetric nuclear-to-cytoplasmic (N/C) ratio of a single cell. The RRBS framework was insensitive to the selection of seeds and image pixel noise. The robustness of the RRBS framework was verified through the convergence of the N/C ratio searching algorithm. The relative standard deviation of the N/C ratio between different randomly selected seed sets was only 2%. This technique is useful for various in vitro assays on single-cell analyses. [ABSTRACT FROM AUTHOR]

The scattering properties and refractive indices (RI) of tissue are important parameters in tissue optics. These parameters can be determined from quantitative phase images of thin slices of tissue blocks. However, the changes in RI and structure of cells due to fixation and paraffin embedding might result in inaccuracies in the estimation of the scattering properties of tissue. In this study, three-dimensional RI distributions of cells were measured using digital holographic microtomography to obtain total scattering cross sections (TSCS) of the cells based on the first-order Born approximation. We investigated the slight loss of dry mass and drastic shrinkage of cells due to paraformaldehyde fixation and paraffin embedding removal processes. We propose a method to compensate for the correlated changes in volume and RI of cells. The results demonstrate that the TSCS of live cells can be estimated using restored cells. The percentage deviation of the TSCS between restored cells and live cells was only -8%. Spatially resolved RI and scattering coefficients of unprocessed oral epithelium ranged from 1.35 to 1.39 and from 100 to 450 cm-1, respectively, estimated from paraffinembedded oral epithelial tissue after restoration of RI and volume. [ABSTRACT FROM AUTHOR]

Background Infiltrating macrophage count (IMC) is found to correlate with the progression and prognosis of many human cancers. Methods This study used immunohistochemistry to measure the IMC (macrophages/high-power field [HPF]) in 92 specimens of oral squamous cell carcinoma (OSCC). Results A significantly increased IMC was found in OSCCs with larger tumor size, positive lymph node metastasis, more advanced clinical stages, or recurrence (all ps < .05). Kaplan-Meier survival analysis found that OSCC patients with IMC >196 macrophages/HPF had a significantly shorter disease-free (p = .001, log-rank test) or overall survival (p < .001, log-rank test) than OSCC patients with IMC <196 macrophages/HPF. Multivariate Cox regression analyses showed that IMC >196 macrophages/HPF was an independent predictor for poor disease-free (p = .005) and overall survival of patients with OSCC (p = .015). Conclusions The IMC can predict the progression and prognosis of OSCCs in Taiwan. © 2009 Wiley Periodicals, Inc. Head Neck, 2010 [ABSTRACT FROM AUTHOR]

Tumor-associated macrophages (TAMs) and cyclooxygenase-2 (COX-2) are associated with invasion, angiogenesis, and poor prognosis in many human cancers. However, the role of TAMs in human basal cell carcinoma (BCC) remains elusive. We found that the number of TAMs infiltrating the tumor is correlated with the depth of invasion, microvessel density, and COX-2 expression in human BCC cells. TAMs also aggregate near COX-2 expressing BCC tumor nests. We hypothesize that TAMs might activate COX-2 in BCC cells and subsequently increase their invasion and angiogenesis. TAMs are a kind of M2 macrophage derived from macrophages exposed to Th2 cytokines. M2-polarized macrophages derived from peripheral blood monocytes were cocultured with BCC cells without direct contact. Coculture with the M2 macrophages induced COX-2-dependent invasion and angiogenesis of BCC cells. Human THP-1 cell line cells, after treated with phorbol myristate acetate (PMA), differentiated to macrophages with M2 functional profiles. Coculture with PMA-treated THP-1 macrophages induced COX-2-dependent release of matrix metalloproteinase-9 and subsequent increased invasion of BCC cells. Macrophages also induced COX-2-dependent secretion of basic fibroblast growth factor and vascular endothelial growth factor-A, and increased angiogenesis in BCC cells.Journal of Investigative Dermatology (2009) 129, 1016–1025; doi:10.1038/jid.2008.310; published online 9 October 2008 [ABSTRACT FROM AUTHOR]

Cyclooxygenase-2 (COX-2) is critical for tumor formation, angiogenesis, metastasis, and prognosis. In this study, the role of COX-2 in antiapoptosis, tumorigenesis, and angiogenesis of human basal cell carcinoma (BCC) cells was investigated. Transfection of COX-2 constitutive expression vector into a BCC cell line yielded several overexpressing clones. All transfectants demonstrated remarkable resistance to ultraviolet B-induced apoptosis (confirmed by flow cytometry analysis, morphological change, and DNA fragmentation). Immunoblot analysis revealed marked increases in apoptosis-regulated genes Mcl-1 and Bcl-2. A 10-fold concentrated conditioned medium from COX-2-overexpressing BCC cells exhibited higher angiogenic activity in Matrigel plug and human umbilical vein endothelial cell tube formation assay. Cells exhibited increased levels of vascular endothelial growth factor-A (VEGF-A) mRNA and protein, and secreted VEGF-A and basic fibroblast growth factor (bFGF). COX-2-specific small interfering RNA markedly reduced the secreted species. After 7 weeks of inoculation, the tumor volume of COX-2-overexpressing cells in severe combined immunodeficient mice was significantly greater than that of vector control cells. Immunohistochemical analysis of CD31-positive vessels revealed a two-fold increase in microvessel density in COX-2 tumors, compared to control vector tumors. Our data indicate that Mcl-1 and Bcl-2, as well as VEGF-A and bFGF, are downstream effectors of COX-2-induced antiapoptosis and angiogenesis, respectively.Journal of Investigative Dermatology (2006) 126, 1143–1151. doi:10.1038/sj.jid.5700191; published online 9 March 2006 [ABSTRACT FROM AUTHOR]

Contact dermatitis simulating erythema multiforme can be caused by many allergens. The chemical agent 1,2-ethanedithiol, which serves as a protective group in chemical synthesis, has hitherto only been implicated as an irritant. We report on a 22-year-old female chemistry student who developed widespread erythema multiforme-like lesions after local contact with 1,2-ethanedithiol. Many target lesions were observed bilaterally on her hands, forearms, arms, and on her forehead. One such lesion was histologically compatible with erythema multiforme. The patient had a positive patch test to 1,2-ethanedithiol, whereas none of 30 healthy subjects showed a positive reaction. However, eight of the 30 controls (26.7%) developed irritant reactions to 1,2-ethanedithiol. Cautious handling of the compound is a prudent precaution. [ABSTRACT FROM AUTHOR]