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C-Y Chou

Publications and source records attributed to C-Y Chou.

8 recordsLinked to original sources
PubMed2006

Colloid interaction and pair correlation function of one-dimensional colloid-polymer systems.

The interaction and pair correlation function of weakly charged colloidal particles in quasi-one-dimensional colloid-polymer systems are determined by enhanced video microscopy and digital image analysis. The pair correlation function is found to depend not only on the polymer concentration, but also on the degree of confinement; in particular, it depends on whether the channel width is such that mutual passage of the colloid particles is possible or not. These findings are compared with exact results on short-range order in linear continuous systems.

Journal Article↗
PubMed2006

One-dimensional diffusion of colloids in polymer solutions.

For colloid-polymer systems confined in one-dimensional channels, the diffusion of the colloidal particles is obtained by tracking individual particles using enhanced video microscopy and digital image analysis. For short times, the diffusion is normal, of the Fickian type, with mean-squared displacement varying linearly with time. For long times, however, the mean-squared displacement is found to increase more slowly with time, being proportional to the square root of time, in agreement with the theoretical prediction for diffusion of hard rods in one dimension in which mutual crossing of the particles cannot take place. The crossover from short-time to long-time diffusion is observed and is found to depend on the colloid and polymer concentrations. Unexpectedly, for small polymer-to-colloid size ratios, it is the polymer rather than the colloid concentration which has a leading effect on the colloid diffusion.

Journal Article↗
PubMed2004

Three-dimensional power Doppler imaging of early-stage cervical cancer.

OBJECTIVES: To characterize intratumoral vascularization in early-stage cervical cancer by three-dimensional (3D) power Doppler ultrasound. METHODS: One hundred and forty-one patients with carcinoma of the uterine cervix and 30 normal controls were studied by transvaginal 3D power Doppler ultrasound. The tumor volume of the cervical cancer was determined. The blood flow within the tumor or normal cervix was measured and expressed as the vascularization index (VI), flow index (FI) and vascularization flow index (VFI). RESULTS: Of the 141 patients with cervical cancer, 44 patients had undergone prior cervical conization. Eighty-seven patients had measurable cervical tumors, of whom five had had prior conization. Abundant intratumoral power Doppler signals could be detected, and the VI, FI and VFI were significantly elevated in cervical cancer patients compared with women with a normal cervix and patients in whom no cervical tumor could be detected (P < 0.05, one-way ANOVA). We observed four types of intratumoral vascularity patterns, which did not significantly differ in VI, FI and VFI: localized, peripheral, scattered and single-vessel types. Cervical tumor volume was positively correlated with FI (linear regression, r = 0.373, P = 0.001), but not with VI or VFI. CONCLUSIONS: 3D power Doppler ultrasound provides a useful tool to investigate intratumoral vascularization and volume of cervical cancer.

Adult↗
PubMedDate not supplied

Signet-ring stromal tumor of the ovary: a case report.

Signet-ring stromal tumor of the ovary is a rare disease and only four cases had been reported in the literature. The primary significance is to differentiate this benign disease from the malignant signet-ring adenocarcinoma. We report a case of signet-ring stromal tumor of the ovary in a 76-year-old woman who had suffered from low abdominal pain for one month. She underwent left oophorectomy, and the diagnosis was made based on immunohistochemical and electron microscopic characteristics. She has been well and free from recurrence for one year.

Aged↗
PubMedDate not supplied

Evidence of human papillomavirus infection, enhanced phosphorylation of retinoblastoma protein, and decreased apoptosis in sarcomatoid squamous cell carcinoma of uterine cervix.

Sarcomatoid squamous cell carcinoma (SSCC) of the uterine cervix, characterized by biphasic components of sarcomatoid and squamous neoplastic cells, is a rare entity with uncertain pathogenesis. To date, less than 20 cases have been mentioned. Although the rarity of this diagnosis makes it difficult to draw firm conclusions from limited data, it does seem that SSCC is an aggressive tumor. In this study, we present a 31-year-old patient with abnormal vaginal bleeding. The diagnosis of SSCC was confirmed through pathologic examinations from hysterectomy specimen. Its epithelial origin was demonstrated by immunohistochemical studies. The expression of p53, HER2/neu, and c-kit was not enhanced in this tumor. Importantly, it was human papillomavirus type 16, positive by polymerase chain reaction and in situ hybridization studies. Enhanced immunostaining for phospho-retinoblastoma protein and decreased apoptosis compared with the squamous cell carcinoma counterpart were observed. This report characterizes the first description of molecular features in SSCC that may account for its aggressive behavior.

Adult↗
PubMedDate not supplied

The distribution and differential risks of human papillomavirus genotypes in cervical preinvasive lesions: A Taiwan Cooperative Oncologic Group Study.

To clarify the distribution and relative risk of different human papillomavirus (HPV) genotypes in cervical preinvasive lesions, 1246 women with abnormal Papanicolaou smear including atypical squamous cell of unknown significance (ASCUS), atypical glandular cell of unknown significance (AGUS), low-grade squamous intraepithelial lesion (LSIL), and high-grade squamous intraepithelial lesion (HSIL) were enrolled in a multicenter, cross-sectional study. Colposcopy and HPV tests with hybrid capture 2 and polymerase chain reaction-reverse line blot were performed. The prevalences of HPV in ASCUS/AGUS-negative histology, ASCUS/AGUS, LSIL, HSIL, and invasive cancer were 33.8%, 38.3%, 74.9%, 84.3% and 100%, respectively, with an overall positive rate of 68.8%. The most common HPV types were HPV 16 (18.5%), 52 (16.5%), 58 (13.2%), 33, 51, 53, 18, 39, 59, 66, MM8, and 31. In comparing the relative risk of HPV infection in different disease status, LSIL and HSIL/carcinoma had a 4.64 (95% CI: 2.98-7.24) and 10.53 (95% CI: 6.69-16.58) folds of risk of high-risk HPV infection than the negative group. The same was true in mixed HPV infection, but not in low-risk type infection. Looking into each high-risk HPV type, the relative infection risks for LSIL and HSIL/carcinoma, in comparison with the negative group, were 1.67 (0.63-4.43) and 8.67 (3.46-21.70), 2017 (1.01-4.68) and 3.04 (1.42-6.47), and 1.40 (0.52-3.77) and 5.22 (2.07-13.19) for HPV type 16, 52 and 58, respectively. The study confirmed the high prevalence and risky nature of HPV 52 and 58 in Taiwanese population and conveyed the need to include these HPV types in vaccine development.

Adult↗