Preferential inactivation of paediatric solid tumour cells by sequential exposure to Merocyanine 540-mediated photodynamic therapy and Edelfosine: implications for the ex vivo purging of autologous haematopoietic stem cell grafts

Paediatric solid tumours exhibit steep dose-response curves to alkylating agents and are therefore considered candidates for high-dose chemotherapy and autologous stem cell support. There is growing evidence that autologous stem cell grafts from patients with solid tumours are frequently contaminated with live tumour cells. The objective of this study was to perform, in a preclinical purging model, an initial assessment of the safety and efficacy of a two-step purging procedure that combined Merocyanine 540-mediated photodynamic therapy (MC540-PDT) with a brief exposure to the alkyl-lysophospholipid, Edelfosine. Human and murine bone marrow cells and Neuro-2a murine neuroblastoma, SK-N-SH human neuroblastoma, SK-ES-1 and U-2 OS human osteosarcoma, G-401 and SK-NEP-1 human Wilms' tumour, and A-204 human rhabdomyosarcoma cells were exposed to a fixed dose of MC540-PDT followed by a brief incubation with graded concentrations of Edelfosine. Survival was subsequently assessed by in vitro clonal assay or, in the case of CD34-positive haematopoietic stem cells, by an immunohistochemical method. Combination purging with MC540-PDT and Edelfosine depleted all tumour cells by >4 log while preserving at least 15% of murine granulocyte/macrophage progenitors (CFU-GM), 34% of human CFU-GM, and 31% of human CD34-positive cells. The data suggest that combination purging with MC540-PDT and Edelfosine may be useful for the ex vivo purging of autologous stem cell grafts from patients with paediatric solid tumours.     

Validity of retinal oxygen saturation analysis: Hyperspectral imaging in visible wavelength with fundus camera and liquid crystal wavelength tunable filter

The purpose of this paper was to investigate the feasibility of a newly developed hyperspectral fundus imaging camera with a liquid crystal tunable filter. The intensities of different wavelengths of light transmitted through an artery, vein, and the area surrounding these vessels and reflected out were measured, and the differential spectral absorptions were analyzed. Measurements were made from 16 normal eyes and from two artificial capillaries. The ratios of absorption (ROA) of arteries to veins from 500 to 580 nm (range 1) and from 600 to 720 nm (range 2) were calculated. For all eyes, the ROA_range1 was larger than ROA_range2. The ROA obtained from the artificial capillary filled with blood saturated with oxygen or nitrogen was similar to that of simulated data of oxy- and deoxyhemoglobin extinction rate. Most ROAs of human eyes were lower than those of the simulated data and the artificial capillaries. Oxygen saturation analysis by hyperspectral fundus imaging of retinal vessels were qualitatively in agreement with thein vitro analysis or simulated values. However, further improvements are necessary to evaluate the oxygen saturation quantitatively in the retinal blood vessels.     

Preparation of poly(p‐oxybenzoyl) crystals using direct polymerization of p‐hydroxybenzoic acid in the presence of boronic anhydrides

Poly(p‐oxybenzoyl) (POB) crystals were prepared by reaction‐induced crystallization during direct polymerization of p‐hydroxybenzoic acid in the presence of boronic anhydrides. Polymerizations were carried out at 300 °C in dibenzyltoluene at a concentration of 1% with three kinds of anhydrides of boronic acid such as 3,4,5‐trifluorophenylboronic acid (TFB), 4‐methoxyphenylboronic acid (MPB) and 4‐biphenylboronic acid (BPB). The POB crystals were formed as precipitates in the solution and the morphology was considerably influenced by both the structure of the boronic anhydride and its concentration (c_B). Needle‐like crystals were firmed in the presence of TFB anhydride (TFBA) at c_Bs of 5 and 10 mol % by the spiral growth of lamellae. Spherical aggregates of slab‐like crystals were formed at c_Bs from 50 to 100 mol %. The polymerization with MPB anhydride and BPB anhydride (BPBA) also yielded the needle‐like crystals at c_Bs of 50 and 5 mol %, respectively. The polymerization with TFBA at lower c_B was favorable to prepare the needle‐like crystal. Molecular weight was also influenced by the structure of the boronic anhydride and c_B. M_n increased generally with c_B and BPBA gave the highest M_n of 14.7 × 10³ at c_B of 100 mol %. The loose packing of the molecules in the crystal caused by the bulkiness of the end‐groups made the polymerization in the crystals more efficiently. Morphology and molecular weight of the POB crystals could be controlled by the chemical structure and the content of boronic anhydride. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.     

Flexible host frameworks with diverse cavities in inclusion crystals of bile acids and their derivatives

We have systematically investigated structures and properties of inclusion crystals of bile acids and their derivatives. These steroidal compounds form diverse host frameworks having zero‐, one‐ and two‐dimensional cavities, causing various inclusion behaviors towards many organic compounds. The diverse host frameworks exhibit the following guest‐dependent flexibility. First, the frameworks mainly depend on the included guests in size and shape. The size‐dependence is quantitatively estimated by the parameter PCcavity, which is the volume ratio of a guest molecule to a host cavity. The resulting values of PCcavity lie in the range of 42–76%. Second, each of the host frameworks has its own range of the values. Some guests can employ two different frameworks with the boundary values, explaining formation of polymorphic crystals. Third, the host frameworks are selected by host–guest interactions through weak hydrogen bonds, such as NH/π and CH/O. The weak hydrogen bonds play an important role for various selective inclusion processes. Fourth, the host frameworks are dynamically exchangeable, resulting in intercalation and polymerization in the cavities. These static and dynamic structures of the frameworks demonstrate great potential of crystalline organic inclusion compounds as functional materials. © 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 9: 124–135; 2009: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.20171     

Modular synthesis of the ClickFerrophos ligand family and their use in rhodium- and ruthenium-catalyzed asymmetric hydrogenation

A series of diphosphine ClickFerrophos ligands (CF), based on a triazoleferrocene backbone, was synthesized in a four-step sequence via click chemistry methodology. In addition to the four previously synthesized ligands CF1, CF4, CF7 and CF10, six novel CF ligands CF2–3 and CF5–8 were prepared. Hydrogenation reactions of alkenes and ketones were significantly improved upon by using CF ligands as rhodium- or ruthenium-complexes in which the % ee values can be optimized by choosing the appropriate CF ligand depending on the substrate.     

Printed circuit rat-race-type directional couplers for larger power-split ratio

Two different types of 5/2-wavelength rat-race-type directional couplers with a remarkably increased power-split ratio for a realizable ring-impedance, in particular which are useful for millimeter-wave circuits suffering from the severe restriction on the usable impedance range, are described. Experimental corroboration is provided in the microwave region (at 8 GHz).