Low energy X-ray dosimeter based on LYSO:Ce fluorescent powder.

Cerium-doped lutetium yttrium orthosilicate (LYSO:Ce) powder has been synthesized by the co-precipitation method. The influence of the Ce3+ doping concentration on the lattice structure and luminescence characteristics of LYSO:Ce powder was investigated by X-ray diffraction (XRD) and photoluminescence (PL). The XRD measurement indicates that the lattice structure of LYSO:Ce powder was not changed by doping ions.

Extended state observer-based fixed-time trajectory tracking control of autonomous surface vessels with uncertainties and output constraints.

A fixed-time trajectory tracking control of autonomous surface vessels (ASVs) subject to unmeasured speed is studied in this work. By using the homogeneity-based Lyapunov method, the unknown system states, including the unmeasured speed and lumped disturbances, are estimated by using a novel extended state observer (ESO) within fixed time. Subsequently, using the estimated states, the task of fixed-time tracking is completed with the aid of a newly proposed output-constrained power integrator method, which makes the vessel position and heading strictly within the predefined output constraints, and the tracking errors can be reduced to a range of zero under the continuous control action.

Cdc25A-inhibitory properties and antineoplastic activity of bisperoxovanadium analogues.

Bisperoxovanadium (bpV) compounds are irreversible protein tyrosine phosphatase (PTP) inhibitors with a spectrum of activity distinct from that of vanadium salts. We studied the efficacy of a panel of bpVs as antineoplastic agents in vitro and in vivo with a view to investigating phosphatases as potential antineoplastic targets. The Cdc25A dual-specificity phosphatase is an oncoprotein required for progression through G(1)-S.

Regulation of multiple tumor microenvironment markers by overexpression of single or paired combinations of ErbB receptors.

The progression of primary tumors to an invasive phenotype requires dynamic changes in multiple cellular and local tumor microenvironment markers. In this study, we report a genomic approach to assess gene transcriptional changes upon overexpression of ErbB receptors, in vitro and in vivo, focusing on markers involved in the regulation of the tumor microenvironment. ErbB receptors (ErbB-1/epidermal growth factor receptor, ErbB-2, ErbB-3, and ErbB-4) were stably overexpressed in a polyclonal cell population as single or paired combinations using murine and human breast cell models.

Differential regulation of tumor angiogenesis by distinct ErbB homo- and heterodimers.

Interactions between cancer cells and their microenvironment are critical for the development and progression of solid tumors. This study is the first to examine the role of all members of the ErbB tyrosine kinase receptors (epidermal growth factor receptor [EGFR], ErbB-2, ErbB-3, or ErbB-4), expressed singly or as paired receptor combinations, in the regulation of angiogenesis both in vitro and in vivo. Comparison of all receptor combinations reveals that EGFR/ErbB-2 and ErbB-2/ErbB-3 heterodimers are the most potent inducers of vascular endothelial growth factor (VEGF) mRNA expression compared with EGFR/ErbB-3, EGFR/ErbB-4, ErbB-2/ErbB-4, and ErbB-3/ErbB-4.

Retroviral delivery of connexin genes to human breast tumor cells inhibits in vivo tumor growth by a mechanism that is independent of significant gap junctional intercellular communication.

The mechanism by which gap junction proteins, connexins, act as potent tumor suppressors remains poorly understood. In this study human breast tumor cells were found to exhibit diverse gap junction phenotypes including (a) undetectable Cx43 and no intercellular communication (HBL100); (b) low levels of Cx43 and sparse intercellular communication (MDA-MB-231); and (c) significant levels of Cx43 and moderate intercellular communication (Hs578T). Although retroviral delivery of Cx43 and Cx26 cDNAs to MDA-MB-231 cells did not achieve an expected substantial rescue of intercellular communication, overexpression of connexin genes did result in a dramatic suppression of tumor growth when connexin-expressing MDA-MB-231 cells were implanted into the mammary fat pad of nude mice.

Antiangiogenic and antimetastatic properties of Neovastat (AE-941), an orally active extract derived from cartilage tissue.

A novel naturally occurring antiangiogenic agent isolated from cartilage, referred to as Neovastat (AE-941), was examined for its efficacy against tumor neovascularization and progression. Exposure to Neovastat results in ex ovo antiangiogenic properties in the chorioallantoid membrane of chicken embryo (71% decrease in the angiogenic index as compared to the basic fibroblast growth factor (bFGF) treated control embryos, P < 0.0001).