Summary of the Activities of the Working Group I on High Energy and Collider Physics

This is a summary of the projects undertaken by the Working Group I on High Energy Collider Physics at the Eighth Workshop on High Energy Physics Phenomenology (WHEPP8) held at the Indian Institute of Technology, Mumbai, January 5-16, 2004. The topics covered are (i) Higgs searches (ii) supersymmetry searches (iii) extra dimensions and (iv) linear collider.Comment: summary of Working Group I at the Eighth Workshop on High Energy Physics Phenomenology (WHEPP8), I.I.T., Mumbai, January 5-16, 200

Azo Anion Radical Complex of Rhodium as a Molecular Memory Switching Device: Isolation, Characterization, and Evaluation of Current–Voltage Characteristics

Two rare examples of azo anion diradical complexes of Rh­(III) are reported. These complexes showed excellent memory switching properties with a large ON/OFF ratio and are suitable for RAM/ROM applications. Their electronic structures have been elucidated using a host of physical methods, including X-ray crystallography, variable-temperature magnetic susceptibility measurement, cyclic voltammetry, electron paramagnetic resonance spectroscopy, and density functional theory. The results indicate a predominant triplet state description of the systems with two ferromagnetically coupled radicals

PEG Linker Length Strongly Affects Tumor Cell Killing by PEGylated Carbonic Anhydrase Inhibitors in Hypoxic Carcinomas Expressing Carbonic Anhydrase IX

Hypoxic tumors overexpress membrane-bound isozymes of carbonic anhydrase (CA) CA IX and CA XII, which play key roles in tumor pH homeostasis under hypoxia. Selective inhibition of these CA isozymes has the potential to generate pH imbalances that can lead to tumor cell death. Since these isozymes are dimeric, we designed a series of bifunctional PEGylated CA inhibitors (CAIs) through the attachment of our preoptimized CAI warhead 1,3,4-thiadiazole-2-sulfonamide to polyethylene glycol (PEG) backbones with lengths ranging from 1 KDa to 20 KDa via a succinyl linker. A detailed structure−thermal properties and structure–biological activity relationship study was conducted via differential scanning calorimetry (DSC) and via viability testing in 2D and 3D (tumor spheroids) cancer cell models, either CA IX positive (HT-29 colon cancer, MDA-MB 231 breast cancer, and SKOV-3 ovarian cancer) or CA IX negative (NCI-H23 lung cancer). We identified PEGylated CAIs DTP1K 28, DTP2K 23, and DTP3.4K 29, bearing short and medium PEG backbones, as the most efficient conjugates under both normoxic and hypoxic conditions, and in the tumor spheroid models. PEGylated CAIs did not affect the cell viability of CA IX-negative NCI-H23 tumor spheroids, thus confirming a CA IX-mediated cell killing for these potential anticancer agents

Azo Anion Radical Complex of Rhodium as a Molecular Memory Switching Device: Isolation, Characterization, and Evaluation of Current–Voltage Characteristics

Two rare examples of azo anion diradical complexes of Rh­(III) are reported. These complexes showed excellent memory switching properties with a large ON/OFF ratio and are suitable for RAM/ROM applications. Their electronic structures have been elucidated using a host of physical methods, including X-ray crystallography, variable-temperature magnetic susceptibility measurement, cyclic voltammetry, electron paramagnetic resonance spectroscopy, and density functional theory. The results indicate a predominant triplet state description of the systems with two ferromagnetically coupled radicals

pH-Sensitive Multiligand Gold Nanoplatform Targeting Carbonic Anhydrase IX Enhances the Delivery of Doxorubicin to Hypoxic Tumor Spheroids and Overcomes the Hypoxia-Induced Chemoresistance

Hypoxia is a common feature of solid tumors contributing to resistance to chemotherapy. Selective delivery of chemotherapeutic drugs to hypoxic tumor niche remains an unsolved issue. For this purpose, we constructed a gold nanoplatform targeting carbonic anhydrase IX (CA IX) epitope, which is overexpressed in hypoxic tumor cells versus in normal tissues. We designed compatible low-molecular weight carbonic anhydrase inhibitor (CAI) ligands and doxorubicin (Dox) ligands and optimized protocols for efficient decoration of gold nanoparticles (Au NPs) to achieve both good targeting ligand density and optimum drug loading, while preserving colloidal stability. The optimized Dox-HZN-DTDP@Au NPs-LA-PEG2000-CAI (THZN) nanoplatform was proved to be very efficient toward killing HT-29 tumor cells, especially under hypoxic conditions, as compared with the nontargeting nanoplatform. This also mediated the effective release of doxorubicin in the lysosomes following internalization, as revealed by confocal microscopy. Furthermore, using tumor spheroids as a representative model for hypoxic solid tumors, our THZN nanoplatform enhanced the selective delivery of doxorubicin up to 2.5 times and minimized chemoresistance, showing better tumor drug penetration as compared to that in free drug treatment. Our technology is the first CA IX-targeting gold nanoplatform for efficient delivery of doxorubicin to hypoxic tumors in a controlled fashion, with the perspective to improve the therapy of solid tumors and minimize chemoresistance

Working group report: High energy and collider physics

This is a summary of the projects undertaken by the working group I on high energy and collider physic