Many living organisms have amazing control over their color, shape, and morphology for camouflage, communication, and even reproduction in response to interplay between environmental stimuli. Such interesting phenomena inspire scientists to develop smart soft actuators/robotics via integrating color‐changing functionality based on polymer films or elastomers. However, there has been no significant progress in synergistic color‐changing and shape‐morphing capabilities of life‐like material systems such as hydrogels. Herein, we reported a new class of bioinspired synergistic fluorescence‐color‐switchable polymeric hydrogel actuators based on supramolecular dynamic metal–ligand coordination. Artificial hydrogel apricot flowers and chameleons have been fabricated for the first time, in which simultaneous color‐changing and shape‐morphing behaviors are controlled by the subtle interplay between acidity/alkalinity, metal ions, and temperature. This work has made color‐changeable soft machines accessible and is expected to hold wide potential applications in biomimetic soft robotics, biological sensors, and camouflage.

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Most colorectal carcinomas (CRCs) arise from adenomas through an archetypal pathogenic pathway, the adenomacarcinoma-metastasis sequence. Aberrant expression of ␤-catenin, p16, E-cadherin and c-myc appears to have played important roles in the development and/or progression of CRC, but their precise distribution pattern and associations in different pathologic loci along CRC's pathogenic pathway have not been thoroughly examined. In this study, a tissue microarray (TMA) containing 85 advanced CRCs in different Dukes stages was constructed. In each of 85 cases, tissue specimens from normal mucosa and primary carcinomas in different layers of the bowel wall were included in the TMA. Tissue specimens from matched adenoma, lymph node metastases and distant metastases were obtained from 22, 21 and 21 cases, respectively. Expression patterns of ␤-catenin, p16, E-cadherin and c-myc were evaluated by immunohistochemistry. The results revealed that nuclear expression of ␤-catenin, p16 and c-myc was quantitatively increased from normal mucosa to premalignant adenoma, primary carcinoma and lymph node metastatic carcinoma; the frequency of nuclear overexpression of ␤-catenin and p16 in lymph node metastases was significantly higher than that in distant metastases (p < 0.05). These results suggest an association between nuclear overexpression of ␤-catenin and/or p16 and CRC lymph node metastasis but not distant metastasis. The results also showed that correlative high nuclear expression of ␤-catenin and c-myc was observed in primary carcinomas involving the serosa and lymph node metastases (p < 0.05) but not in other pathologic regions of CRCs, suggesting that the tumor microenvironment in different pathologic loci of colorectal tumorigenesis and progression may influence cmyc responsiveness to ␤-catenin/Tcf activation. © 2003 Wiley-Liss, Inc. Key words: colorectal carcinoma; heterogeneity; immunohistochemistry; fluorescence in situ hybridizationColorectal carcinoma (CRC) is one of the most common malignancies and a major cause of cancer death in the developed countries. 1 The incidence of CRC varies greatly around the world, with the highest incidence in the Western world and the lowest in India. 2 In urban Shanghai, China, the incidence of CRC increased rapidly and doubled over a 23-year period (1972-1994). 3 It is now widely accepted that most CRCs arise from adenomas through a process described as the adenoma-carcinoma-metastasis sequence. Tumorigenesis and progression of CRC is believed to be influenced by the genetic accumulation of abnormalities of numerous tumor suppressor genes and oncogenes, including nuclear overexpression of ␤-catenin, p16 and c-myc and loss expression of membranous E-cadherin. 4 -8 However, it is well known that the distribution pattern of gene expression detected by immunohistochemistry in tumor tissue, especially in certain histologically and genetically heterogeneous tumors, is often substantially varied. Germane to the present study, previous studies have documented heterogeneous expression ...

Novel-morphological Fe3O4 nanosheets with magnetochromatic property have been prepared by a modified solvothermal method. Such nanosheets could form one-dimension photonic crystal under an external magnetic field. The Fe3O4 nanosheets suspension could strongly diffract visible light and display varied colors with changing the intensity of the magnetic field. The photonic response is rapid, fully reversible and widely tunable in the entire visible spectrum. Excellent magnetic properties of these Fe3O4 nanosheets are exhibited with a high saturation magnetization (82.1 emu/g), low remanence (13.85 emu/g) and low coercive force (75.95 Oe). The amount of the solvent diethylene glycol (DEG) plays a key role in the formation of the sheet-shaped morphology. When the ratio of the DEG reaches 100%, the growing of the crystal plane (111) of Fe3O4 is inhibited and the sheet-like Fe3O4 crystals are formed.