The use of gold nanorods for photoacoustic molecular imaging with simultaneous multiple targeting is reported. Multiple targeting is done by utilizing the tunable optical absorption property of gold nanorods. This technique allows multiple molecular signatures to be obtained by simply switching laser wavelength. HER2 and EGFR were chosen as the primary target molecules for examining two cancer cells, OECM1 and Cal27. Both in vitro and in vivo mouse model imaging experiments were performed, with contrast enhancement of up to 10 dB and 3.5 dB, respectively. The potential in improving cancer diagnosis is demonstrated.

The Fe(3)O(4) nanoparticles, tailored with maleimidyl 3-succinimidopropionate ligands, were conjugated with paclitaxel molecules that were attached with a poly(ethylene glycol) (PEG) spacer through a phosphodiester moiety at the (C-2')-OH position. The average number of paclitaxel molecules/nanoparticles was determined as 83. These nanoparticles liberated paclitaxel molecules upon exposure to phosphodiesterase.

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A wettability gradient to transport a droplet across superhydrophobic to hydrophilic surfaces is fabricated on combining a structure gradient and a self-assembled-monolayer (SAM) gradient. The combination of these two gradients is realized with a simple but versatile SAM technique, in which the textured silicon wafer strip is placed vertically in a bottle that contains a decyltrichlorosilane solution to form concurrently a saturated SAM below the liquid surface and a wettability gradient above. The platform fabricated in this way has a water-contact angle from 151.2 degrees to 39.7 degrees; the self-transport distance is hence increased significantly to about 9 mm. A theoretical model that approximates the shape of a moving drop to a spheroidal cap is developed to predict the self-transport behavior. Satisfactory agreement is shown for most regions except where the hysteresis effect is unmeasurable and an unsymmetrical deformation occurs. A double-directional gradient surface to alter the direction of movement of a droplet is also realized. The platforms we developed serve not only to transport a fluid over a long distance but also for a broad spectrum of biomedical applications such as protein adsorption, cell adhesion and DNA-based biosensors.

Photoacoustic (PA) imaging has been used mainly for anatomical and functional imaging. Although functionalized nanoparticles also have been developed for PA molecular imaging, only single targeting has been demonstrated. In this study, PA imaging of multiple targets using gold nanorods is demonstrated experimentally using HER2 and CXCR4 as target molecules. The two corresponding monoclonal antibodies were conjugated to two types of gold nanorod with different aspect ratios. Gold nanorods with mean aspect ratios of 5.9 and 3.7 exhibited peak optical absorptions at 1000 and 785 nm, respectively. Appropriate selection of laser irradiation wavelength enhances PA signals by 7-12 dB and allows signals from gold nanorods corresponding to specific bindings to be distinguished. This approach potentially allows the expression levels of different oncogenes of cancer cells to be revealed simultaneously.

Fossil dinosaur embryos are surprisingly rare, being almost entirely restricted to Upper Cretaceous strata that record the late stages of non-avian dinosaur evolution. Notable exceptions are the oldest known embryos from the Early Jurassic South African sauropodomorph Massospondylus and Late Jurassic embryos of a theropod from Portugal. The fact that dinosaur embryos are rare and typically enclosed in eggshells limits their availability for tissue and cellular level investigations of development. Consequently, little is known about growth patterns in dinosaur embryos, even though post-hatching ontogeny has been studied in several taxa. Here we report the discovery of an embryonic dinosaur bone bed from the Lower Jurassic of China, the oldest such occurrence in the fossil record. The embryos are similar in geological age to those of Massospondylus and are also assignable to a sauropodomorph dinosaur, probably Lufengosaurus. The preservation of numerous disarticulated skeletal elements and eggshells in this monotaxic bone bed, representing different stages of incubation and therefore derived from different nests, provides opportunities for new investigations of dinosaur embryology in a clade noted for gigantism. For example, comparisons among embryonic femora of different sizes and developmental stages reveal a consistently rapid rate of growth throughout development, possibly indicating that short incubation times were characteristic of sauropodomorphs. In addition, asymmetric radial growth of the femoral shaft and rapid expansion of the fourth trochanter suggest that embryonic muscle activation played an important role in the pre-hatching ontogeny of these dinosaurs. This discovery also provides the oldest evidence of in situ preservation of complex organic remains in a terrestrial vertebrate.

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Objective. Because thrombospondin 1 (TSP-1) inhibits angiogenesis and activates latent transforming growth factor ␤ (TGF␤), a potent immunosuppressive and antiinflammatory cytokine, we investigated the prophylactic and therapeutic effects of TSP-1 gene transfer in the collagen-induced arthritis (CIA) model in rats.Methods. Adenoviral vectors encoding mouse TSP-1 (AdTSP-1) or ␤-galactosidase (AdLacZ) as the control were administered by intraarticular injection into CIA rats. The treated ankles were assessed clinically, radiographically, and histologically. Furthermore, expression levels of TSP-1, TGF␤, vascular endothelial growth factor (VEGF), and interleukin-1␤ (IL-1␤) were examined in the synovial tissue.Results. Intraarticular administration of AdTSP-1 reduced the severity of CIA as revealed by examination of the clinical, radiographic, and histologic aspects. Rats treated with AdTSP-1, as compared with AdLacZ-treated controls, were found to have fewer blood vessels (mean ؎ SEM 21.0 ؎ 0.6 versus 45.3 ؎ 2.3/mm 2 ; P < 0.001) and lower production of VEGF (17 ؎ 4 versus 45 ؎ 10 pg/mg of total protein; P < 0.05) and IL-1␤ (374 ؎ 41 versus 526 ؎ 39 pg/mg of total protein; P < 0.05), as well as higher levels of TSP-1 and TGF␤ in the synovial tissue.Conclusion. Direct intraarticular administration of adenoviral vectors encoding TSP-1 significantly ameliorated the clinical course of CIA, accompanied by reduction of synovial hypertrophy and fewer blood vessels. These results suggest that TSP-1 gene therapy may have therapeutic potential for the management of rheumatoid arthritis.