Metallic nanostructures can be designed to effectively reflect different colors at deep-subwavelength scales. Such color manipulation is attractive for applications such as subwavelength color printing; however, challenges remain in creating saturated colors with a general and intuitive design rule. Here, we propose a simple design approach based on all-aluminum gap-plasmonic nanoantennas, which is capable of designing colors using knowledge of the optical properties of the individual antennas. We demonstrate that the individual-antenna properties that feature strong light absorption at two distinct frequencies can be encoded into a single subwavelength-pixel, enabling the creation of saturated colors, as well as a dark color in reflection, at the optical diffraction limit. The suitability of the designed color pixels for subwavelength printing applications is demonstrated by showing microscopic letters in color, the incident polarization and angle insensitivity, and color durability. Coupled with the low cost and long-term stability of aluminum, the proposed design strategy could be useful in creating microscale images for security purposes, high-density optical data storage, and nanoscale optical elements.

The poor prognosis for esophageal cancer could be improved if lesions were detected at an early stage. To detect early esophageal cancer, endoscopic screening of the esophagus with the Lugol dye method was performed in patients with head and neck cancers who were asymptomatic but regarded as being at high risk for synchronous or metachronous esophageal cancer. Of 178 patients screened, 9 had esophageal cancer (5.1%). Eight of these patients (89%) were at early stages with no lymph node metastasis. Most of the lesions (9 of 13 lesions) were not detectable by barium studies or ordinary endoscopic study. The epidemiologic statistical analysis of the patients confirmed that they had a significantly high observed and expected number (O/E) ratio (39.7; P less than 0.001). These results demonstrate the value of endoscopic screening of the esophagus with the Lugol dye method in patients with head and neck cancers and imply that endoscopic screening with the Lugol dye method may be useful for detecting early esophageal cancer in individuals at risk for other causes.

E-cadherin (ECD) is one of subclasses of the cadherin family which plays a major role in the maintenance of intercellular adhesion in epithelial tissues. An immunohistochemical study of ECD expression was performed on gastric adenocarcinoma from 103 patients using our monoclonal antibody for human ECD (HECD-1). ECD was strongly expressed in normal gastric epithelium without exception; however, various staining patterns were observed in cancer tissues. The frequency of tumours with preserved ECD expression (Pre-type) and reduced ECD expression (Rd-type) was 42% and 58% respectively. Tumours with a high frequency of Rd-type expression particularly included: undifferentiated tumours (85%, 46/54), Borrmann's type 4 (90%, 9/10), tumours larger than 2.6 cm in diameter (65%, 53/81), tumours invading beyond the subserosa layer (78%, 46/59), and tumours with infiltrative growth (87%, 41/47). Furthermore, the frequency of Rd-type expression in cases with peritoneal dissemination (82%, 9/11) or lymph node metastasis (73%, 43/59) was significantly higher than that in cases without dissemination or metastasis. These results suggest that ECD might play a key role in the genesis of histological differentiation, and that the reduction of ECD expression may affect the mode of invasion and metastasis of human gastric cancer cells.

The expression of human E-cadherin in normal tissues and in benign and malignant tumors of female genital organs was examined immunohistochemically with a monoclonal antibody, HECD-1, specific for human E-cadherin. The normal tissues included the ovary, fallopian tube, uterine endometrium, uterine cervix, and vagina. E-cadherin was detected clearly in the cell-to-cell boundaries of both normal glandular and squamous epithelia obtained from those tissues. The tumor tissues consisted of 9 ovarian, 7 endometrial, and 4 cervical adenocarcinomas, 12 squamous cell carcinomas of the cervix, including 3 cervical intraepithelial neoplasms, and 5 mesenchymal tumors. E-cadherin also was detected in the cell-to-cell borders of all the epithelial tumors tested, with some reactivity in the cytoplasm of malignant cells, whereas mesenchymal tumors showed no expression. It is noteworthy that poorly differentiated areas of both the adenocarcinomas and squamous cell carcinomas showed less expression of E-cadherin. No difference in the expression of E-cadherin between the primary and metastatic lesions was detected in 10 sets of malignant tumors. E-cadherin may be an important factor among a variety of biologic events that occur during the process of metastasis. However, further studies are needed to clarify this.

Conventional color image sensors employing absorptive color filters exhibit low overall light transmission, resulting in limited signal levels per sensor pixel. This issue is becoming critical because the amount of light to detect at each pixel is decreasing as pixel size decreases. Here, we present a design for transparent, pixel-scale color splitters based on dielectric metasurfaces and show the advantages of using them in color image sensors instead of filters. We demonstrate that the image sensor configurations with the color splitters enhance the amount of detected light by a factor of ∼3.57 compared with a conventional color filter scheme, while preserving the resolution and color image quality.