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hBMSCs are multipotent cells that are useful for tissue regeneration to treat degenerative diseases and others for their differentiation ability into chondrocytes, osteoblasts, adipocytes, hepatocytes and neuronal cells. In this study, biodegradable elastic hydrogels consisting of hydrophilic poly(ethylene glycol) (PEG) and hydrophobic poly(ε-caprolactone) (PCL) scaffolds were evaluated for tissue engineering because of its biocompatibility and the ability to control the release of bioactive peptides. The primary cultured cells from human bone marrow are confirmed as hBMSC by immunohistochemical analysis. Mesenchymal stem cell markers (collagen type I, fibronectin, CD54, integrin1ß, and Hu protein) were shown to be positive, while hematopoietic stem cell markers (CD14 and CD45) were shown to be negative. Three different hydrogel scaffolds with different block compositions (PEG:PCL=6:14 and 14:6 by weight) were fabricated using the salt leaching method. The hBMSCs were expanded, seeded on the scaffolds, and cultured up to 8 days under static conditions in Iscove's Modified Dulbecco's Media (IMDM). The growth of MSCs cultured on the hydrogel with PEG/PCL= 6/14 was faster than that of the others. In addition, the morphology of MSCs seemed to be normal and no cytotoxicity was found. The coating of the vascular endothelial growth factor (VEGF) containing scaffold with Matrigel slowed down the release of VEGF in vitro and promoted the angiogenesis when transplanted into BALB/c nude mice. These results suggest that hBMSCs can be supported by a biode gradable hydrogel scaffold for effective cell growth, and enhance the angiogenesis by Matrigel coating.

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Carrier depletion and transport in a single ZnO nanowire Schottky device have been investigated at 5 K, using cathodoluminescence measurements. An exciton diffusion length of 200 nm has been determined along the nanowire axis. The depletion width is found to increase linearly with the reverse bias. The origin of this unusual dependence in semiconductor material is discussed in terms of charge location and dimensional effects on the screening of the junction electric field.

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Nonpolar InGaN/GaN multiple quantum wells (MQWs) grown on the {11-00} sidewalls of c-axis GaN wires have been grown by organometallic vapor phase epitaxy on c-sapphire substrates. The structural properties of single wires are studied in detail by scanning transmission electron microscopy and in a more original way by secondary ion mass spectroscopy to quantify defects, thickness (1-8 nm) and In-composition in the wells (∼16%). The core-shell MQW light emission characteristics (390-420 nm at 5 K) were investigated by cathodo- and photoluminescence demonstrating the absence of the quantum Stark effect as expected due to the nonpolar orientation. Finally, these radial nonpolar quantum wells were used in room-temperature single-wire electroluminescent devices emitting at 392 nm by exploiting sidewall emission.

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In this article, we demonstrate the fabrication and detection of cancer protein biochips consisting of micro- and nanoarrays whereby pegylated quantum dots (QDs) conjugated to antibodies (Abs) of prostate specific antigens (PSA) were used for the detection of clinical biomarkers such as PSA. BSA which acts as an efficient blocking layer in microarrays, tends to show an interaction with QDs. In view of this fact, we investigated two series of samples which were fabricated in the presence and absence of BSA blocking layer. Variation in the incubation time required for the antigen-antibody interaction to take place, different proteins as controls and the effect of bare QDs on these microarrays, were the three main parameters which were studied in these two series. Samples fabricated in the absence of BSA blocking layer exhibited an extremely high specificity in the detection of cancer proteins and were also marked by negligible nonspecific binding effects of QDs, in stark contrast to the samples fabricated using BSA as a blocking layer. Fabrication of nanoarrays of QD-conjugated PSA Abs having a spot size of nearly 900 nm has also been demonstrated. Thus, we show the potential offered by QDs in in vitro analysis of cancer biomarker imaging.

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The efficacy of a novel transdermal patch containing tropisetron, a 5-hydroxytryptamine 3 (5-HT(3)) receptor antagonist, against emesis induced by anticancer agents were evaluated, in comparison with the effect of traditional tropisetron injection, in rats. The antiemetic effects were assessed via the inhibitory activity on the anticancer agent-induced kaolin-consuming behavior, a pica model representing vomiting in emesis-resistant rodents. The tropisetron patch (10mg/patch, 3.5cm(2)) was attached on the shaved back area of rats. Eight h later, each anticancer agent, cisplatin (10mg/kg, i.v.), cyclophosphamide (200mg/kg, i.p.) or doxorubicin (8mg/kg, i.v.), was administered, and thereafter, daily kaolin consumption was measured for 3 days. In comparison, the effect of daily injection of tropisetron (2mg/kg, i.v.), given 10min, 24 and 48h after the anticancer agent administration, was also evaluated. Kaolin intake greatly increased to 21, 17 and 10 folds of control ingestion on the first day after administration with the anticancer agents, cisplatin, cyclophosphamide and doxorubicin, respectively, and then gradually decreased to near control level on day 3. Such anticancer agent-induced increases in the kaolin consumption were remarkably attenuated by the attachment of tropisetron patch, resulting in the reduction to half levels, which is comparable to the efficacy of daily tropisetron injection. In particular, the blood concentration of tropisetron following patch attachment reached a maximum level of 30-40ng/ml in 12h and exhibited a plateau until detachment of the patch, in contrast to a rapid elimination with a half-life of 2.21h after injection of the drug. Taken together, it is suggested that the novel tropisetron patch could be a promising regimen for the relief of emesis, based on the long-term antiemetic effects on the diverse anticancer agents and the convenience to use the transdermal delivery system for the cancer patients who have difficulty in taking drugs due to surgical operation or gastrointestinal dysfunction.