Clinical outcome of a novel photodynamic therapy technique using acridine orange for synovial sarcomas

Synovial sarcoma (SS) is one of common malignant soft-tissue tumors and is encountered most commonly in children and young adults. It frequently involves or invades major neurovascular structures and bones, and its local recurrence rate after simple resection has been reported to be as high as up to 80%. Because major nerves and vessels, as well as an adequate amount of bone, must be preserved to restore excellent limb function in cases of SS, a surgical technique entailing a low risk of local recurrence is needed. Based on the findings of recent experimental studies conducted by us using a mouse osteosarcoma model, we developed a novel therapeutic technique for SS, consisting of reduction surgery followed by photodynamic therapy using acridine orange (AO-PDT), with or without X-ray irradiation at 5 Gy. A preliminary study revealed that low-dose X-rays also excite AO like photons. After an initial study on cell cultures, this novel technique was applied to six cases of SS. A follow-up of the subjects to determine the clinical outcome revealed that none of the cases treated by AO-PDT, including the four cases treated by additional 5 Gy irradiation and the two cases not receiving any radiation, showed any evidence of recurrence or local/systemic complications during the follow-up period of 19-51 months after the surgery. Therefore, we believe that AO-PDT with 5 Gy irradiation may be an excellent novel therapeutic modality with reduction surgery to salvage excellent limb function in SS involving major nerves and vessels or bones.     

Synthesis and photochemical properties of stilbenophanes tethered by silyl chains. Control of (2pi + 2pi) photocycloaddition, cis-trans photoisomerization, and photocyclization

[structures: see text] Novel macrocyclic and medium-size stilbenophanes tethered by silyl chains were synthesized, and their photochemical and photophysical properties were examined. Direct photoirradiation of macrocyclic stilbenophanes gave intramolecular photocycloadducts stereoselectively, and the efficiency increased with decreasing distance between the two stilbene units. The triplet-sensitized photoreaction of stilbenophanes caused cis-trans photoisomerization. Photoreactions of cis-fixed stilbenophanes under an oxygen atmosphere selectively gave phenanthrenophanes. Fluorescence quantum yields increased with the introduction of silyl substituents, and hence those of silyl-tethered stilbenophanes were larger than that of unsubstituted trans-stilbene. Intramolecular excimer emission was observed when the distances between two stilbene units in the stilbenophanes were sufficiently small.     

Optical waveguide spectrometer based on thin-film glass plates

Commercially available thin-film glass plates have been successfully used for optical waveguide spectroscopy of chemical and biological films adsorbed upon the plates' surfaces. A 50-mum -thick glass plate was placed in contact with two parallel strips of silicone rubber supported on a slide glass. The plate area between the rubber strips served as the waveguiding region, eliminating the negative effect of the substrate on absorbance sensitivity. We coupled white light into the waveguide by focusing the light from a xenon lamp onto one end of a glass fiber and then inserting the other end into a glycerol drop overlaid upon the plate's surface. With a CCD detector, light at wavelengths as short as 360 nm was found to transmit out of the plate's end face. The propagation loss of the waveguide was measured to be 相似文献   

Unusually long-lived light-induced metastable state in a thermochromic copper(II) complex

We report the first observation of a color change from red to purple for a thermochromic complex, [Cu(dieten)2](BF4)2 (dieten = N,N-diethylethylenediamine), which is induced by illuminating with UV light.     

UCS1025A and B,new antitumor antibiotics from the fungus Acremonium species

[structure: see text] UCS1025A and B, novel pentacyclic polyketides with an unprecedented furopyrrolizidine skeleton, were isolated from the fungus Acremonium sp. KY4917. The structures and stereochemistry were elucidated by a combination of two-dimensional NMR and X-ray crystallographic analysis. UCS1025A showed unique chemical equilibria involving three tautomeric isomers and exhibited antimicrobial activity and antiproliferative activity against human tumor cell lines.     

Study of the mechanical interaction between an electromagnetic field and a nanoscopic thin film near electronic resonance

The mechanical interaction between an electromagnetic field and a nanoscopic thin film near electronic resonance is theoretically studied by calculation of Maxwell's stress tensor. As a result of numerical demonstrations for both propagating and evanescent incident waves, the following effects that are specific to this condition have been clarified: (1) The force exerted on a nanoscopic thin film is greatly enhanced near the resonance frequency to the same order of magnitude as for a film with macroscopic thickness. (2) The peak position of the gradient force in its spectrum is highly sensitive to the change in nanoscopic thickness that is due to the polaritonic effect. (3) In a total-reflection region a large enhancement of the repulsive force between the two thin films occurs when the films act as an optical cavity.     

Oxidative decarboxylation of α-keto carboxylic acids by carbonyl oxides

Photosensitized oxygenation of α-keto carboxylic acids in the presence of diazo compounds afforded the corresponding carboxylic acids and carbon dioxide in high yields; oxidative decarboxylation by carbonyl oxides occurred.     

Mode-selective dynamic light scattering spectroscopy: application to the isotropic phase of liquid crystals

We have developed a new method of "mode-selective" dynamic light scattering spectroscopy. This method allows us to study dynamic modes usually hidden behind large fluctuations of a critical mode. Here we apply this method to measurements of three dynamic modes of the isotropic phase of liquid crystals near the isotropic-nematic transition. In conventional methods detecting thermally excited modes, the thermal diffusion and sound modes are usually overwhelmed by the orientational relaxation mode since the intensity of the last mode diverges toward the isotropic-nematic critical point. Thanks to the phase-coherent detection ability of our method, we have successfully observed the thermal diffusion and sound modes without the interference of incoherent critical orientational fluctuations.