المؤلفون: Madsen, Steen J, Christie, Catherine, Huynh, Khoi, Peng, Qian, Uzal, Francisco A, Krasieva, Tatiana B, Hirschberg, Henry

المصدر: Journal of Biomedical Optics. 23(2)

مصطلحات موضوعية: Biomedical and Clinical Sciences, Oncology and Carcinogenesis, Immunology, Vaccine Related, Rare Diseases, Cancer, Orphan Drug, Brain Disorders, Immunization, Brain Cancer, Neurosciences, Prevention, Animals, Brain Neoplasms, Cancer Vaccines, Cell Line, Tumor, Glioma, Histocytochemistry, Immunotherapy, Macrophages, Male, Photochemotherapy, Rats, glioma, immunogenic apoptotic cells, photodynamic therapy-macrophage vaccine, macrophages, photodynamic therapy, allogeneic cells, Optical Physics, Biomedical Engineering, Opthalmology and Optometry, Optics, Ophthalmology and optometry, Biomedical engineering, Atomic, molecular and optical physics

الوصف: Immunotherapy of brain tumors involves the stimulation of an antitumor immune response. This type of therapy can be targeted specifically to tumor cells thus sparing surrounding normal brain. Due to the presence of the blood-brain barrier, the brain is relatively isolated from the systemic circulation and, as such, the initiation of significant immune responses is more limited than other types of cancers. The purpose of this study was to show that the efficacy of tumor primed antigen presenting macrophage (MaF98) vaccines can be increased by: (1) photodynamic therapy (PDT) of the priming tumor cells and (2) intracranial injection of allogeneic glioma cells directly into the tumor site. Experiments were conducted in an in vivo brain tumor development model using Fischer rats and F98 (syngeneic) and BT4C (allogeneic) glioma cells. The results showed that immunization with Ma (acting as antigen-presenting cells), primed with PDT-treated tumor cells (MaF98), significantly slowed but did not prevent the growth of F98-induced tumors in the brain. Complete suppression of tumor development was obtained via MaF98 inoculation combined with direct intracranial injection of allogeneic glioma cells. No deleterious effects were noted in any of the animals during the 14-day observation period.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/8hg5v5bxTest

المؤلفون: Tang, Shuo, Liu, Jian, Krasieva, Tatiana B, Chen, Zhongping, Tromberg, Bruce J

المصدر: Journal of Biomedical Optics. 14(3)

مصطلحات موضوعية: Atomic, Molecular and Optical Physics, Physical Sciences, Acoustics, Animals, Fiber Optic Technology, Humans, Lasers, Microscopy, Fluorescence, Multiphoton, Rats, Skin, Tail, Tendons, multiphoton microscopy, two-photon excited fluorescence, second-harmonic generation, femtosecond fiber lasers, Optical Physics, Biomedical Engineering, Opthalmology and Optometry, Optics, Ophthalmology and optometry, Biomedical engineering, Atomic, molecular and optical physics

الوصف: We implement a fiber-delivered compact femtosecond fiber laser at 1,030-nm wavelength in multiphoton imaging. The laser pulse duration is 150 fs, the average power is 200 mW, and the repetition rate is 40 MHz. The laser measures 200 x 160 x 45 mm in size and its output is delivered through a photonic bandgap fiber. Intrinsic second-harmonic generation signal is excited from rat tail tendon and human skin samples. Two-photon excited fluorescence signal is obtained from human skin tissues stained with exogenous fluorophore. Our results show that femtosecond fiber lasers at 1030-nm wavelength have significant potential in developing compact, all-fiber-based, portable multiphoton systems and endoscopes.

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الوصول الحر: https://escholarship.org/uc/item/7697r8cdTest
https://escholarship.org/content/qt7697r8cd/qt7697r8cd.pdfTest

المؤلفون: Lyubovitsky, Julia G, Krasieva, Tatiana B, Xu, Xiaoman, Andersen, Bogi, Tromberg, Bruce J

المصدر: Journal of Biomedical Optics. 12(4)

مصطلحات موضوعية: Biomedical and Clinical Sciences, Ophthalmology and Optometry, Underpinning research, 1.1 Normal biological development and functioning, Skin, Animals, Hair Follicle, Image Enhancement, Mice, Mice, Transgenic, Microscopy, Fluorescence, Multiphoton, Tomography, Optical, Transcription Factors, hair follicle, dermis, microscopy, two-photon, collagen, extracellular matrix, Optical Physics, Biomedical Engineering, Opthalmology and Optometry, Optics, Ophthalmology and optometry, Biomedical engineering, Atomic, molecular and optical physics

الوصف: We report multiphoton in situ optical sectioning of hair follicles in mice and a preliminary investigation of the pathological hair follicles in a transgenic mouse model. Using this imaging technology, we rapidly obtain detailed three-dimensional (3-D) reconstructions of individual hair follicles. No staining or mechanical sectioning is involved, since multiphoton microscopy coregisters two-photon excited fluorescence (TPF) from cells and second harmonic generation (SHG) signals from the extracellular matrix (ECM). These signals are ideally suited for estimating molecularly encoded hair follicular 3-D geometries, including sizes of the follicular orifices and their angles relative to the skin surface. In the normal hair follicles, spectral separation of SHG signals generated by the ECM of the hair follicle from that of intrinsic cellular fluorescence revealed intricate spatial interaction of the cellular components with the surrounding connective tissue. In the pathological hair follicles, these were clearly modified. In particular, in the transgenic mice, we observed lack of cellular fluorescence and significantly shallower angles of follicular orifices with respect to the skin surface. The combination of TPF with SHG is sensitive to structural changes in cells and extracellular matrix brought on by normal hair follicle physiology and specific gene alterations.

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الوصول الحر: https://escholarship.org/uc/item/7dt1825wTest

المؤلفون: Tang, Shuo, Krasieva, Tatiana B, Chen, Zhongping, Tempea, Gabriel, Tromberg, Bruce J

المصدر: Journal of Biomedical Optics. 11(2)

مصطلحات موضوعية: Atomic, Molecular and Optical Physics, Physical Sciences, Algorithms, Equipment Design, Equipment Failure Analysis, Humans, Image Enhancement, In Vitro Techniques, Microscopy, Fluorescence, Multiphoton, Nonlinear Dynamics, Reproducibility of Results, Sensitivity and Specificity, Signal Processing, Computer-Assisted, Skin, multiphoton microscopy, two-photon excited fluorescence, second harmonic generation, ultrashort pulse, femtosecond laser, Optical Physics, Biomedical Engineering, Opthalmology and Optometry, Optics, Ophthalmology and optometry, Biomedical engineering, Atomic, molecular and optical physics

الوصف: We have developed a multiphoton microscopy (MPM) system using a 12-fs Ti:sapphire laser with adjustable dispersion precompensation in order to examine the impact of pulse duration on nonlinear optical signals. The efficiencies of two-photon-excited fluorescence (TPEF) and second harmonic generation (SHG) were studied for various pulse durations, measured at the sample, ranging from approximately 400 fs to sub-20 fs. Both TPEF and SHG increased proportionally to the inverse of the pulse duration for the entire tested range. Because of improved signal-to-noise ratio, sub-20-fs pulses were used to enhance MPM imaging depth by approximately 160%, compared to 120-fs pulses, in human skin.

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الوصول الحر: https://escholarship.org/uc/item/5fv8p7tfTest

المؤلفون: Kimura, Yuichi, Wilder-Smith, Petra BB, Krasieva, Tatiana B, Arrastia-Jitosho, Anna-Marie A, Liaw, Lih-Huei L, Matsumoto, Koukichi

المصدر: Journal of Biomedical Optics. 2(3)

مصطلحات موضوعية: Biomedical and Clinical Sciences, Engineering, Biomedical Engineering, Physical Sciences, Ophthalmology and Optometry, Atomic, Molecular and Optical Physics, Optical Physics, Opthalmology and Optometry, Optics, Ophthalmology and optometry, Biomedical engineering, Atomic, molecular and optical physics

الوصف: Dentin was visualized using a new fluorescence technique and confocal laser scanning microscopy. Thirty extracted human teeth showing no clinical signs of caries were investigated. All teeth were horizontally sectioned to approximately 200 μm thickness and sections were subjected to different pretreatment conditions as follows: vacuum only, ultrasonication only, sodium hypochlorite only, sodium hypochlorite and vacuum, sodium hypochlorite and ultrasonication, and a combination of sodium hypochlorite, vacuum, and ultrasonication. Some samples were left untreated to serve as control. Following pretreatment, rhodamine 123 fluorescent dye was used for staining at concentrations ranging from 10-3 to 10-7M for 1 to 24 h at pH 6.0, 6.5, or 7.4. Optical staining occurred at pH 7.4 and concentrations ≥ 10-5 M over 3 h or longer. Surface images obtained using confocal laser scanning microscopy were similar to those observed by scanning electron microscopy without the need for sample-altering conventional scanning electron microscope preparation techniques. Subsurface imaging to a depth of approximately 60 μm was achieved using confocal laser microscope techniques. This fluorescence technique offers a useful new alternative for visualization and quantification of dentin. © 1997 Society of Photo-Optical Instrumentation Engineers.

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الوصول الحر: https://escholarship.org/uc/item/4sm556cmTest

المؤلفون: Koenig, Karsten, Krasieva, Tatiana B, Bauer, Eckhard, Fiedler, Ursula, Berns, Michael W, Tromberg, Bruce J, Greulich, Karl-Otto

المصدر: Journal of Biomedical Optics. 1(2)

مصطلحات موضوعية: Biomedical and Clinical Sciences, Space Sciences, Physical Sciences, Optical Physics, Biomedical Engineering, Opthalmology and Optometry, Optics, Ophthalmology and optometry, Biomedical engineering, Atomic, molecular and optical physics

الوصف: Cell damage by low-power 365-nm radiation of a 50-W high-pressure mercury microscopy lamp was studied. Exposure of Chinese hamster ovary (CHO) cells to ultraviolet-A (UVA) radiation >10 kJ/m2 resulted in significant modifications of nicotinamide adenine dinucleotide (NADH) attributed autofluorescence and inhibition of cell division. Single-cell gel electrophoresis (comet assay) revealed UVA-induced single-strand DNA breaks. According to these results, UVA excitation radiation in fluorescence microscopy may damage cells. This has to be considered in vital cell microscopy, e.g., in calcium measurements.

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الوصول الحر: https://escholarship.org/uc/item/8n35r01dTest