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Quantitative image analysis and parameter extraction using a specific implementation of polarization-sensitive optical coherence tomography (OCT) provides differential diagnosis of mucosal pathologies in in-vivo human bladders. We introduce a cross-polarization (CP) OCT image metric called Integral Depolarization Factor (IDF) to enable automatic diagnosis of bladder conditions (assessment the functional state of collagen fibers). IDF-based diagnostic accuracy of identification of the severe fibrosis of normal bladder mucosa is 79%; recurrence of carcinoma on the post-operative scar is 97%; and differentiation between neoplasia and acute inflammation is 75%. The promising potential of CP OCT combined with image analysis in human urology is thus demonstrated in vivo.

In our opinion, Cook detachable coils are safe and effective especially in the treatment of persistent ductus arteriosus with a diameter < or = 2.5 mm. Due to the low costs these coils appear to be superior to other devices in this subgroup of patients.

We combined cross-polarization optical coherence tomography (CP OCT) and non-linear microscopy based on second harmonic generation (SHG) and two-photon-excited fluorescence (2PEF) to assess collagen and elastin fibers and other vascular structures in the development of atherosclerosis, including identification of vulnerable plaques, which remains an important clinical problem and imaging application. CP OCT's ability to visualize tissue birefringence and cross-scattering adds new information about the microstructure and composition of the plaque. However its interpretation can be ambiguous, because backscattering contrast may have a similar appearance to the birefringence related fringes. Our results represent a step towards minimally invasive characterization and monitoring of different stages of atherosclerosis, including vulnerable plaques. CP OCT image of intimal thickening in the human coronary artery. The dark stripe in the cross-polarization channel (arrow) is a polarization fringe related to the phase retardation between two eigen polarization states. It is histologically located in the area of the lipid pool, however this stripe is a polarization artifact, rather than direct visualization of the lipid pool.

The purpose of this study was to evaluate photobleaching of the genetically encoded photosensitizer KillerRed in tumor spheroids upon pulsed and continuous wave (CW) laser irradiation and to analyze the mechanisms of cancer cell death after the treatment. We observed the light-dose dependent mechanism of KillerRed photobleaching over a wide range of fluence rates. Loss of fluorescence was limited to 80% at light doses of 150 J/cm(2) and more. Based on the bleaching curves, six PDT regimes were applied for irradiation using CW and pulsed regimes at a power density of 160 mW/cm(2) and light doses of 140 J/cm(2) , 170 J/cm(2) and 200 J/cm(2). Irradiation of KillerRed-expressing spheroids in the pulsed mode (pulse duration 15 ns, pulse repetition rate 10 Hz) induced predominantly apoptotic cell death, while in the case of CW mode the cancer cells underwent necrosis. In general, these results improve our understanding of photobleaching mechanisms in GFP-like proteins and show the importance of appropriate selection of treatment mode for PDT with KillerRed. Representative fluorescence image of two KillerRed-expressing spheroids before and immediately after CW irradiation.

The development of tumor therapies based on the activation of antitumor immunity requires tumor models that are highly immunogenic. The immunologic response to fluorescent proteins, green fluorescent protein (GFP), or enhanced GFP (EGFP) was demonstrated in different cancer models. However, for live animal imaging, red and far-red fluorescent proteins are preferable, but their immunogenicity has not been studied. We assessed the immunogenicity of the red fluorescent protein, KillerRed (KR), in CT26 murine colon carcinoma. We showed a slower growth and a lower tumor incidence of KR-expressing tumors in comparison with nonexpressing ones. We found that KR-expressing lung metastases and rechallenged tumors were not formed in mice that had been surgically cured of KR-expressing primary tumors. The effect of low-dose cyclophosphamide (CY) treatment was also tested, as this is known to activate antitumor immune responses. The low-dose CY therapy of CT26-KR tumors resulted in inhibition of tumor growth and improved mouse survival. In summary, we have established a highly immunogenic tumor model that could be valuable for investigations of the mechanisms of antitumor immunity and the development of new therapeutic approaches.

Low-intensity noncoherent luminescent radiation stimulates reparative processes in soft tissue wounds of rats. The stimulation is dependent on the frequency of fight pulsation and the luminescence spectrum.Key Words: luminescent radiation; laser radiation; phototherapy, soft tissue wounds Special fiber-optic sources of luminescent fight with a relatively broad spectral range (50-100 nm) have recently been developed [6]. In contrast to monochromatic laser radiation, these sources provide monochromatized radiation or, taking into account the mechanism of its creation and its specific features, luminescent monochromatized noncoherent radiation (LMNR) [7]. LMNR is not subject to the restrictions imposed on the premises and work regime of personnel operating laser phototherapeutic apparatus [8]. In light of the findings confmnmg the absence of a specific influence of lasers on biological objects [7,10], the replacement of laser fight in phototherapeutic procedures [2-4,9] by noncoherent broad-band radiation seems expedient. MATERIALS AND METHODSThe sources of low-intensity noncoherent radiation were based on two-layer optical fibers with a transparent shell of methylmethacrylate and butylmethacrylate copolymer with a polystyrene core containing the photoluminescent additives phenalemine-439 and phenalemine-160), and on optical fibers made from fluorine-substituted methylmethacrylate with a methylmethacrylate core with rhodamine 6g-chloride. These additives enabled us to obtain three Medical Institute, Nizhnii Novgorod. (Presented by B. A. Korolev, Member of the Russian Academy ol Medical Sciences) different LMNR: red (600-680 nm, spectral maximum 635 urn), orange (600-680 nan, spectral maximum 605 nm), and green (500-580 nm, spectral maximum 540 nm).Experiments were performed on rats of the same fitter after a 10-day quarantine period during which the animals were kept in individual cages under the same conditions. Rats with signs of spontaneous pathology were not included in the study. Wounds were produced with a scalpel on the back (5-era cuts limited by the fascia were made along the body axis) under local Novocain (0.25%) anesthesia. The wound was closed immediately with three silk sutures placed at a distance of 1 cm from each other. The operation field was pretreated with 5% iodine [1].The reparative processes were controlled by determining scar fu'mness after complete epithelization by the method of wound tensiometry [2]. In addition, visual and histological studies of the scars were performed on days 3, 5, 7, and 10 of wound modeling.The treatment sessions with LMNR were started the day after the operation. An optical polymer fiber 0.8 mm in diameter was used. The distance between the distal end of the fiber and the tissue was 1-2 mm; exposure time was 15 rnin. The power density was 20 mW/cm :. The procedure was performed every day during a 5-day period. The ardmals were euthanized on days 5 and 7 by ether overdose. Tissue samples with scars

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