In Vitro Chemosensitivity Using the Histoculture Drug Response Assay in Human Epithelial Ovarian Cancer

The choice of chemotherapeutic drugs to treat patients with epithelial ovarian cancer has not depended on individual patient characteristics. We have investigated the correlation between in vitro chemosensitivity, as determined by the histoculture drug response assay (HDRA), and clinical responses in epithelial ovarian cancer. Fresh tissue samples were obtained from 79 patients with epithelial ovarian cancer. The sensitivity of these samples to 11 chemotherapeutic agents was tested using the HDRA method according to established methods, and we analyzed the results retrospectively. HDRA showed that they were more chemosensitive to carboplatin, topotecan and belotecan, with inhibition rates of 49.2%, 44.7%, and 39.7%, respectively, than to cisplatin, the traditional drug of choice in epithelial ovarian cancer. Among the 37 patients with FIGO stage Ⅲ/Ⅳ serous adenocarcinoma who were receiving carboplatin combined with paclitaxel, those with carboplatin-sensitive samples on HDRA had a significantly longer median disease-free interval than patients with carboplatin- resistant samples (23.2 vs. 13.8 months, p＜0.05), but median overall survival did not differ significantly (60.4 vs. 37.3 months, p＝0.621). In conclusion, this study indicates that HDRA could provide useful information for designing individual treatment strategies in patients with epithelial ovarian cancer

A Fuzzy-Based Multimedia Content Retrieval Method Using Mood Tags and Their Synonyms in Social Networks

The preferences of Web information purchasers are rapidly evolving. Cost-effectiveness is now becoming less regarded than cost-satisfaction, which emphasizes the purchaser’s psychological satisfaction. One method to improve a user’s cost-satisfaction in multimedia content retrieval is to utilize the mood inherent in multimedia items. An example of applications using this method is SNS (Social Network Services), which is based on folksonomy, but its applications encounter problems due to synonyms. In order to solve the problem of synonyms in our previous study, the mood of multimedia content is represented with arousal and valence (AV) in Thayer’s two-dimensional model as its internal tag. Although some problems of synonyms could now be solved, the retrieval performance of the previous study was less than that of a keyword-based method. In this paper, a new method that can solve the synonym problem is proposed, while simultaneously maintaining the same performance as the keyword-based approach. In the proposed method, a mood of multimedia content is represented with a fuzzy set of 12 moods of the Thayer model. For the analysis, the proposed method is compared with two methods, one based on AV value and the other based on keyword. The analysis results demonstrate that the proposed method is superior to the two methods

Temperature-dependent evolutions of excitonic superfluid plasma frequency in a srong excitonic insulator candidate, Ta2_2NiSe5_5

We investigate an interesting anisotropic van der Waals material, Ta$_{2}$NiSe$_{5}$, using optical spectroscopy. Ta$_{2}$NiSe$_{5}$ has been known as one of the few excitonic insulators proposed over 50 years ago. Ta$_{2}$NiSe$_{5}$ has quasi-one dimensional chains along the $a$-axis. We have obtained anisotropic optical properties of a single crystal Ta$_{2}$NiSe$_{5}$ along the $a$- and $c$-axes. The measured $a$- and $c$-axis optical conductivities exhibit large anisotropic electronic and phononic properties. With regard to the $a$-axis optical conductivity, a sharp peak near 3050 cm$^{-1}$ at 9 K, with a well-defined optical gap ($\Delta^{EI} \simeq$ 1800 cm$^{-1}$) and a strong temperature-dependence, is observed. With an increase in temperature, this peak broadens and the optical energy gap closes around $\sim$325 K($T_c^{EI}$). The spectral weight redistribution with respect to the frequency and temperature indicates that the normalized optical energy gap ($\Delta^{EI}(T)/\Delta^{EI}(0)$) is $1-(T/T_c^{EI})^2$. The temperature-dependent superfluid plasma frequency of the excitonic condensation in Ta$_{2}$NiSe$_{5}$ has been determined from measured optical data. Our findings may be useful for future research on excitonic insulators.Comment: 17 pages, 5 figure

Immobilized Polydiacetylene Lipid Vesicles on Polydimethylsiloxane Micropillars as a Surfactin-Based Label-Free Bacterial Sensor Platform

Accurate detection and sensing of bacteria are becoming increasingly important not only in microbiology but in a variety of fields including medicine, food, public health, and environmental science. However, even new rapid methods are not convenient enough. Here, we describe a simple and efficient label-free bacterial detection system using the polydiacetylene (PDA) liposomes immobilized on the 3D polydimethylsiloxane (PDMS) micropillars. Our system utilizes the colorimetric response of amine functionalized PDA vesicles to surfactin, a bacterial cyclic lipopeptide commonly released by Gram-positive Bacillus species as an antibiotic. To improve the sensitivity of PDA vesicles to surfactin by increasing the number and surface area of immobilized vesicles, the PDA vesicles were immobilized on the micropillar structure to give a hierarchical 3D PDA vesicle structure. For the fabrication of the 3D micropillar structure, polydimethylsiloxane (PDMS) was used to overcome the limitations imposed by silicon-based fabrication. In contrast to the 2D-PDA-PDMS system, which could only hardly detect the presence of 500 μM surfactin, the 3D-PDA-PDMS system could efficiently detect the presence of 5 μM surfactin and the initial presence of 4 × 101 cells/ml of Bacillus subtilis NCIB3610, which actively produces surfactin. Furthermore, bacterial strains that are known to produce no surfactin, such as Staphylococcus aureus Newman, Escherichia coli DH5α, and Pseudomonas aeruginosa PA14 were not detected by our system suggesting that the 3D-PDA-PDMS system is highly specific to surfactin but not to other chemicals produced by bacteria. Taken together, our results suggest that the 3D-PDA-PDMS system can sensitively and selectively be used for the high throughput detection and screening of biotechnologically important surfactin-producing bacterial strains