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We present fiber-based polarization-sensitive swept-source optical coherence tomography (SS-OCT) based on continuous source polarization modulation. The light source is a frequency swept laser centered at 1.31 microm with a scanning rate of 20 kHz. The incident polarization is modulated by a resonant electro-optic modulator at 33.3 MHz, which is one-third of the data acquisition frequency. The zeroth- and first-order harmonic components of the OCT signals with respect to the polarization modulation frequency have the polarimetric information of the sample. By algebraic and matrix calculations of the signals, this system can measure the depth-resolved Jones matrices of the sample with a single wavelength scan. The phase fluctuations of the starting trigger of wavelength scan and the polarization modulation are cancelled by monitoring the OCT phase of a calibration mirror inserted into the sample arm. We demonstrate the potential of the system by the measurement of chicken breast muscle and the volumetric measurement of an in vivo human anterior eye segment. The phase retardation image shows an additional contrast in the fibrous tissue such as the collagen fiber in the trabecular meshwork and sclera.

Purpose: To evaluate trabeculectomy blebs by using 3-dimensional anterior segment optical coherence tomography (OCT)., Methods: We prospectively examined 4 eyes of 4 patients who developed filtering blebs after trabeculectomy. A 1310-nm high-speed OCT prototype was used to image the 3-dimensional structure of the filtering blebs., Results: The 3-dimensional structure of the filtering blebs was clearly observed in the OCT images. Three types of filtering blebs were observed: diffuse blebs in 2 eyes, an encapsulated bleb in 1 eye, and a nonfunctioning cystic bleb in 1 eye. The volume of each bleb was 9.97, 1.10, 0.76, and 0.88 mm3, respectively. En-face OCT images clearly showed the aqueous outflow channels at the margins of the scleral flaps., Conclusion: Three-dimensional OCT allows objective and noninvasive assessment of filtering blebs after trabeculectomy.

A series of 3'-(substituted phenyl)deschloroepibatidine analogs (5a-j) were synthesized. The alpha4beta2( *) and alpha7 nicotinic acetylcholine receptor (nAChR) binding properties and functional activity in the tail-flick, hot-plate, locomotor, and body temperature tests in mice of 5a-j were compared to those of the nAChR agonist, nicotine (1), epibatidine (4), and deschloroepibatidine (13), the partial agonist, varenicline (3), and the antagonist 2'-fluoro-3'-(substituted phenyl)deschloroepibatidine analogs (7a-j). Unlike epibatidine and deschloroepibatidine, which are potent agonists in the tail-flick test, 5a-k show no or very low antinociceptive activity in the tail-flick or hot-plate test. However, they are potent antagonists in nicotine-induced antinociception in the tail-flick test, but weaker than the corresponding 2'-fluoro-3'-(substituted phenyl)deschloroepibatidines.

Phase retardation of in vivo human retinal nerve fiber layer (RNFL) is quantitatively measured by two methods--polarization-sensitive spectral-domain optical coherence tomography (PS-SD-OCT) and scanning laser polarimetry (SLP). An en face cumulative phase retardation map is calculated from the three-dimensional (3-D) phase retardation volume of healthy and glaucomatous eyes measured by PS-SD-OCT. It is shown that the phase retardation curves around the optic nerve head measured by PS-SD-OCT and SLP have similar values except near the retinal blood vessels. PS-SD-OCT can measure the cumulative phase retardation of RNFL as well as SLP, which will allow the evaluation of RNFL for glaucomatous eyes.

Objective: To describe the 3-dimensional (3-D) imaging of the pathologic changes in the foveal photoreceptor layer in eyes with central serous chorioretinopathy (CSC) using high-speed optical coherence tomography (OCT)., Design: Prospective observational case series., Participants: Twenty-seven eyes of 27 consecutive patients with various stages of CSC., Methods: A prototype high-speed OCT system was fabricated for patient examinations based on Fourier domain OCT. The system had a sensitivity of 98 dB, a tissue axial resolution of 4.3 mum, and an acquisition rate of approximately 18700 axial scans per second. Three-dimensional imaging was performed based on a raster-scan protocol., Main Outcome Measures: Anatomic features of CSC distinguished by 3-D OCT., Results: A line corresponding to backreflection from the external limiting membrane (ELM) was visible in images from eyes with all stages of CSC, including 6 in the acute, 5 in the chronic, and 9 in the recurrent phase of retinal detachment and 11 examined in the quiescent phase (including 4 reexamined after reattachment). Backreflection from the photoreceptor inner and outer segment junction (IS/OS) was missing before but present after reattachment. The ELM line bordered the photoreceptor nuclear and inner segment layers, clearly showing that CSC primarily alters the outer segment (OS) layer. Punctate areas of intense reflectivity were observed more frequently in the OS layer of detached retinas in cases of chronic or recurrent versus acute CSC (P<0.05, chi-square test). Of 11 eyes with reattached macula, 3 eyes with large defects in the subfoveal IS/OS had poor visual acuity (VA), and 8 eyes with small or no defects had good VA (P<0.05 and P<0.001, chi-square test). Decreases in foveal full and outer thickness were associated with VA loss (P<0.05 and P<0.001, Spearman rank correlation test)., Conclusions: Three-dimensional OCT imaging delineates the microstructural changes that occur within the photoreceptor layers and demonstrates the spatial relationship between the laterally spreading or scattering microstructures and the fovea in eyes with CSC. Visualization of the 3-D relationship between the ELM and each photoreceptor layer before and after macular reattachment facilitates understanding of anatomic and vision changes that result from CSC.

Purpose: To demonstrate the improved visualization of pathological foveal structures by a prototytpe Fourier-domain optical coherence tomography instrument (FD-OCT)., Materials and Methods: We constructed a prototype FD-OCT instrument with an axial resultion of 4.3, m in tissues and an acquisition rate of approximately 18,700 axial scans per second. A raster-scan protocol comprising 256 x 256 axial scans was used in a 2.8 x 2.8 mm area to obtain a 3D-OCT data set. Images of the fovea were obtained in patients with central serous chorioretinopathy(5 eyes of 5 patients), macular hole (6 eyes of 5 patients), pigment epithelial detachment (PED : 4 eyes of 4 patients), and epiretinal membrane (4 eyes of 4 patients)., Results: Normal fovea showed two lines corresponding to a strong backreflection from the external limiting membrane (ELM) and the inner and outer segment junctions (IS/OS). With the exception of the eyes with epiretinal membrane, the IS/ OS line that corresponded to the region where the photoreceptor layer shifted inward disappeared in all eyes. The ELM lines were clearly observed in the same region, except for the one eye with the most steeply protruding PED., Conclusions: The use of FD-OCT enables improved visualization of the pathological structural changes in the foveal photoreceptor layer of patients with macular diseases.

Scattering optical coherence angiography (S-OCA) is a noninvasive imaging method that is based on the high-speed standard 800nm band spectral-domain optical coherence tomography (SD-OCT) and the ultra-high-resolution SD-OCT which has the axial resolution of 6.1 mum and 2.9 mum in tissue, respectively. In this paper, we have demonstrated the use of this method for in vivo human retinal imaging. A three-dimensional view of the choroidal vasculature was obtained by segmenting the choroidal vessels; this was done using intensity threshold based binarization at each depth plane relative to the retinal pigment epithelium. A vascular projection image was obtained by integrating the segmented choroidal vasculature. In order to assess the feasibility of the proposed method, we compared these images with those obtained using existing invasive methods such as fluorescein angiography and indocyanine green angiography. Clinically worthful images are obtained from the application of S-OCA to the agerelated macular degeneration and polypoidal choroidal vasculopathy.

Line-field spectral domain optical coherence tomography (LF-SDOCT) has been developed for very high-speed three-dimensional (3D) retinal imaging. By this technique, the A-line rate significantly improved to 823,200 A-lines/s for single frame imaging and 51,500 A-lines/s for continues frame imaging. The frame rate at continues frame imaging is 201 fps. This 3D acquisition speed is more than two fold higher acquisition speed than the standard flying spot SD-OCT. In this paper, the integration time of the camera was optimized for the in vivo retinal measurement and the degradation of the lateral resolution due to the ocular aberrations was suppressed by introducing the pupil stop. Owing to an optimal integration time, the motion artifact can be significantly suppressed. Also a pupil stop was employed in order to enhance the contrast of the OCT image for the effect of ocular aberrations. The in vivo 3D retinal imaging with 256 cross-sectional images (256 A-lines/image) was successfully performed in 1.3 seconds, corresponding to 0.8 volume/s. The maximum on-axis system sensitivity was measured to be 89.4 dB at a depth of 112 mum with an axial resolution of 7.4 mum in tissue. It is shown that LF-SDOCT might have a sensitivity advantage in comparison to the flying spot SD-OCT in the ultra high-speed acquisition mode.

Retinal, choroidal and scleral imaging by using swept-source optical coherence tomography (SS-OCT) with a 1-microm band probe light, and high-contrast and three-dimensional (3D) imaging of the choroidal vasculature are presented. This SS-OCT has a measurement speed of 28,000 A-lines/s, a depth resolution of 10.4 microm in tissue, and a sensitivity of 99.3 dB. Owing to the high penetration of the 1-microm probe light and the high sensitivity of the system, the in vivo sclera of a healthy volunteer can be observed. A software-based algorithm of scattering optical coherence angiography (S-OCA) is developed for the high-contrast and 3D imaging of the choroidal vessels. The S-OCA is used to visualize the 3D choroidal vasculature of the in vivo human macula and the optic nerve head. Comparisons of S-OCA with several other angiography techniques including Doppler OCA, Doppler OCT, fluorescein angiography, and indocyanine green angiography are also presented.

Objective: To demonstrate the advantages of 3-dimensional imaging of macular hole pathology using new-generation high-speed optical coherence tomography (OCT)., Design: Prospective observational case series., Participants: Twenty-one eyes from 20 consecutive patients diagnosed with a macular hole., Methods: A prototype high-speed OCT system was built based on a Fourier-domain OCT (FD OCT) technology for patient examination. The system has achieved sensitivity of approximately 98 decibels, axial resolution of approximately 4.3 mum in tissue, and an acquisition rate of approximately 18,700 axial scans per second. Three-dimensional imaging of macular hole pathology was performed based on a raster scan protocol consisting of 256x256 axial scans. All patients were imaged with 3-dimensional OCT, Stratus OCT, and OCT Ophthalmoscope C7., Main Outcome Measures: Images of macular hole pathologies obtained by 3-dimensional OCT and standard OCT instruments., Results: The 3-dimensional OCT imaging successfully generated realistic 3-dimensional images of the vitreofoveal interface and intraretinal microstructures associated with a macular hole. The 3-dimensional overview of the vitreofoveal interface was helpful in gaining an immediate understanding of the dynamic interactions of the vitreous and fovea. Observations of consecutive en face images in combination with conventional longitudinal images and of cross-sectional images in combination with sectioned volume images enabled identification of intraretinal microstructures and their 3-dimensional extension associated with a macular hole, such as subfoveal structural changes after vitreous traction, connection of the flap to intraretinal structures, the external limiting membrane (ELM) and its disruption, and elevated photoreceptor inner and outer segments delineated by the ELM. The appearance of inner-wall images of a macular hole produced by photoreceptor inner and outer segment backreflection varied throughout macular hole stages., Conclusions: Three-dimensional imaging of macular holes with high-speed OCT based on FD OCT technology offers 3-dimensional overviews that facilitate understanding of the abnormalities in the vitreofoveal interface. It also provides consecutive orthogonal images that allow much more precise and minute observation of 3-dimensionally extending intraretinal structural changes associated with a macular hole than conventional OCT imaging, especially in the photoreceptor inner and outer segments.

Purpose: To describe 3-dimensional optical coherence tomography (OCT) findings in a case of granular corneal dystrophy., Methods: A 1310-nm high-speed swept-source OCT prototype was used to image the 3-dimensional structures of the cornea of a patient with granular corneal dystrophy., Results: Three-dimensional OCT clearly showed multiple highly reflective lesions, corresponding to the deposits in the cornea. Volume of the deposits within the central 1.5 mm of the cornea was 0.11 mm and occupied 2.98% of the corneal volume., Conclusions: Three-dimensional OCT allows objective and noninvasive assessment of granular corneal dystrophy.

A new ursane-type triterpene, named as cheiranthic acid (1), was isolated from the MeOH extract of whole plants of Oenothera cheiranthifolia (Onagraceae) along with an isomeric pair of known oleanane- and ursane-type triterpenes (arjunolic acid and asiatic acid) and three flavonol glucuronide analogues (quercetin 3-O-glucuronide, its n-butyl ester, and myricetin 3-O-glucuronide). Their structures were elucidated based on spectroscopic evidence.

Cystatin C (CysC) is an endogenous cysteine proteases inhibitor produced by mature astrocytes in the adult brain. Previously we isolated CysC as a factor activating the glial fibrillary acidic protein (GFAP) promoter, and showed that CysC is expressed in astrocyte progenitors during development. Here we show that protease inhibitor activity increased daily in conditioned medium, and that this activity was mainly a result of CysC released from primary cultured cells. Human CysC added to the culture medium of primary brain cells increased the number of GFAP-positive and nestin-positive cells. Human CysC also increased the number of neurospheres formed from embryonic brain, and thus it increases the number of neural stem/precursor cells in a manner similar to glycosylated rat CysC. The addition of a neutralizing antibody, on the other hand, greatly decreased the number of GFAP and glutamate aspartate transporter (GLAST)-positive astrocytes. This decrease was reversed by the addition of CysC but not by another cysteine protease inhibitor. Thus, the promotion of astrocyte development by CysC appears to be independent of its protease inhibitor activity. The antibody increased the number of oligodendrocytes and their precursors. Therefore, CysC modifies glial development in addition to its activity against neural stem/precursor cells.

Noninvasive angiography is demonstrated for the in vivo human eye. Three-dimensional flow imaging has been performed with high-speed spectral-domain optical coherence tomography. Sample motion is compensated by two algorithms. Axial motion between adjacent A-lines within one OCT image is compensated by the Doppler shift due to bulk sample motion. Axial displacements between neighboring images are compensated by a correlation-based algorithm. Three-dimensional vasculature of ocular vessels has been visualized. By integrating volume sets of flow images, two-dimensional images of blood vessels are obtained. Retinal and choroidal blood vessel images are simultaneously obtained by separating the volume set into retinal part and choroidal parts. These are corresponding to fluorescein angiogram and indocyanine angiogram.

Fiber-based high-speed polarization-sensitive Fourier domain optical coherence tomography (PS-FD-OCT) is developed at 840 nm wavelength using polarization modulation method. The incident state of polarization is modulated along B-scan. The spectrometer has a polarizing beamsplitter and two line-CCD cameras operated at a line rate of 27.7 kHz. From the 0th and 1st orders of the spatial frequencies along the B-scanning, a depth-resolved Jones matrix can be derived. Since continuous polarization modulation along B-scan causes fringe washout, equivalent discrete polarization modulation is applied to biological measurements. For the demonstration, an in vitro chicken breast muscle, an in vivo finger pad, and an in vivo caries lesion of a human tooth are measured. Three dimensional phase retardation images show the potentials for applying the system to biological and medical studies.

The natural product withaferin A (WFA) is a potent angiogenesis inhibitor and it targets the ubiquitin-proteasome pathway in vascular endothelial cells. We generated a biotinylated affinity analog WFA-LC(2)B for use as a probe to study angiogenesis. WFA-LC(2)B inhibits angiogenic sprouting in vitro and it causes levels of ubiquitinated proteins to increase in tumor necrosis factor-alpha-treated human umbilical vein endothelial cells, confirming the retention of WFA's biological activity. We show that WFA-LC(2)B forms protein adducts in endothelial cells which are competed by free WFA in vivo. This WFA-LC(2)B analog will be useful to isolate the biological target of WFA.

High-speed complex full-range Fourier domain optical coherence tomography (FD-OCT) is demonstrated. In this FD-OCT, the phase modulation of a reference beam (M scan) and transversal scanning (B scan) are simultaneously performed. The Fourier transform method is applied along the direction of the B scan to reconstruct complex spectra, and the complex spectra comprise a full-range OCT image. Because of this simultaneous B-M-mode scan, the FD-OCT requires only a single A scan for each single transversal position to obtain a full-range FD-OCT image. A simple but slow version of the FD-OCT visualizes the cross section of a plastic plate. A modified fast version of this FD-OCT investigates a sweat duct in a finger pad in vivo and visualizes it with an acquisition time of 27 ms.

A set of fully automated algorithms that is specialized for analyzing a three-dimensional optical coherence tomography (OCT) volume of human skin is reported. The algorithm set first determines the skin surface of the OCT volume, and a depth-oriented algorithm provides the mean epidermal thickness, distribution map of the epidermis, and a segmented volume of the epidermis. Subsequently, an en face shadowgram is produced by an algorithm to visualize the infundibula in the skin with high contrast. The population and occupation ratio of the infundibula are provided by a histogram-based thresholding algorithm and a distance mapping algorithm. En face OCT slices at constant depths from the sample surface are extracted, and the histogram-based thresholding algorithm is again applied to these slices, yielding a three-dimensional segmented volume of the infundibula. The dermal attenuation coefficient is also calculated from the OCT volume in order to evaluate the skin texture. The algorithm set examines swept-source OCT volumes of the skins of several volunteers, and the results show the high stability, portability and reproducibility of the algorithm.

Jones matrix imaging of biological samples by a polarization-sensitive Fourier-domain optical coherence tomography has been demonstrated using a two-dimensional CCD camera to obtain two spectra corresponding to the orthogonal polarization components simultaneously. The measurement results of a quarter-wave plate are compared between the two incident polarization sets, H-V linear and R-L circular polarization. Jones matrix imaging of the bovine tendon is demonstrated. Measured Jones matrix images are converted to equivalent Müller matrix images. Local polarization properties are obtained by longitudinal differentiation of Jones matrix components. The layered structure of the bovine tendon and birefringence are revealed.

Using positron emission tomography (PET) with a specific and selective radioligand targeting nicotinic acetylcholine receptor (nAChR) would allow us to better understand various nAChR related CNS disorders. The use of radiolabeled nAChR antagonists would provide a much safer pharmacological profile, avoiding most peripheral side effects that might be generated from radiolabeled nAChR agonists even at the tracer level; thus, PET imaging with nAChR antagonists would facilitate clinical application. A potent and selective nAChR antagonist was labeled and characterized with PET in non-human primates. Its high brain uptake, high signal-to-noise ratio, and high specific binding strongly suggest a great potential to carry out imaging studies in humans. In addition, the use of a C-11 radiotracer would allow us to perform multiple PET studies in the same individual within a short time frame. The presence of an iodine atom in the molecule also allows the possibility to label with radioiodine for SPECT studies.

A numerical deconvolution method to cancel lateral defocus in Fourier domain optical coherence tomography (FD-OCT) is presented. This method uses a depth-dependent lateral point spread function and some approximations to design a deconvolution filter for the cancellation of lateral defocus. Improved lateral resolutions are theoretically estimated; consequently, the effect of lateral superresolution in this method is derived. The superresolution is experimentally confirmed by a razor blade test, and an intuitive physical interpretation of this effect is presented. The razor blade test also confirms that this method enhances the signal-to-noise ratio of OCT. This method is applied to OCT images of medical samples, in vivo human anterior eye segments, and exhibits its potential to cancel the defocusing of practical OCT images. The validity and restrictions involved in each approximation employed to design the deconvolution filter are discussed. A chromatic and a two-dimensional extensions of this method are also described.

We demonstrate 3-D optical coherence tomography using only 1-D mechanical scanning. This system uses the principle of Fourier domain optical coherence tomography for depth resolution, 1-D imaging for lateral vertical resolution, and mechanical scanning by a galvanometer for lateral horizontal resolution. An in vivo human fingerpad is investigated in three dimensions with an image size of 480 points (vertical) x 300 points (horizontal) x 1024 points (depth), which corresponds to 2.1 x 1.4 x 1.3 mm. The acquisition time for a single cross section is 1 ms and that for a single volume is 10 s. The system sensitivity is 75.6 dB at a probe beam power of 1.1 mW.

A two- and three-dimensional swept source optical coherence tomography (SS-OCT) system, which uses a ready-to-ship scanning light source, is demonstrated. The light source has a center wavelength of 1.31 mum, -3 dB wavelength range of 110 nm, scanning rate of 20 KHz, and high linearity in frequency scanning. This paper presents a simple calibration method using a fringe analysis technique for spectral rescaling. This SS-OCT system is capable of realtime display of two-dimensional OCT and can obtain three-dimensional OCT with a measurement time of 2 s. In vivo human anterior eye segments are investigated two- and three-dimensionally. The system sensitivity is experimentally determined to be 114 dB. The three-dimensional OCT volumes reveal the structures of the anterior eye segments, which are difficult to observe in two-dimensional OCT images.

A series of 3'-substituted deschloroepibatidine analogues (3a-g and 4) showed high affinity for alpha4beta2 binding and relatively weak affinity for alpha7 nAChRs. The 3'-ethynyl (3g) and 3'-fluoro (3a) analogues with K(i) values of 0.02 and 0.037 nM, respectively, were the most potent. Even though the alpha4beta2 binding affinity of several of the analogues were equal to that of epibatidine, all of the compounds were weak agonists in the antinociceptive, hypothermia, and spontaneous activity test in mice. In contrast, all of the compounds were functional antagonists of nicotine-induced antinociception. In general, compounds 3a-g and 4 were more potent in the tail-flick assay than the hot-plate test. For example, the 3'-fluoro analogue 3a and the N-methyl-3'-iodo analogue 4 showed AD(50) values of 0.07 and 0.04 microg/kg, respectively, in the tail flick test and only 35 and 0% inhibition at 20 and 10 microg/kg in the hot-plate assay, respectively. These results suggest that these compounds will be highly useful for identifying which specific receptor subtypes are involved in each of nicotine's pharmacological effects. The high affinity of the N-methyl-3'-iodo analogue 4 combined with its weak agonist and potent antagonist activity suggests that carbon-11 and iodine-123 analogues may be useful as PET and SPECT ligands, respectively, for studying nAChRs in vivo.

Line-field Fourier-domain interferometry that is capable of a fast three-dimensional (3-D) shape measurement is proposed. This system is constructed from a combination of a conventional Fourier-domain interferometer and a one-dimensional imaging system. This system directs a line-shaped focus onto a specimen, and a two-dimensional shape can be calculated from a single-shot image of the CCD camera without any mechanical scan. An aspherical mirror and a Japanese coin are presented as a 3-D shape measurement example.

Standard Fourier domain optical coherence tomography (FD-OCT) and line-field Fourier domain optical coherence tomography (LF-FDOCT) are described. The standard FD-OCT has the measurement speed of 36 frames/sec and one frame consisting 500 A-scans. The LF-FDOCT is an improved version of FD-OCT and determines a cross section of a sample without any mechanical scanning. The LF-FDOCT has the measurement speed of 30 frames/sec, which is corresponding to 480 KH/ A-scan. A galvano-meter is introduced into the LF-FDOCT and it enables three-dimensional OCT measurement with only one-dimensional mechanical scanning.

The central nervous system of the mammalian embryo is organized according to the expression of region-specific transcription factors along the anteroposterior and/or the dorsoventral axis. For example, the dorsal ventricular zone (VZ) of the embryonic spinal cord expresses Pax3 and Pax7, the ventral VZ expresses Pax6, and the more ventral VZ expresses Nkx2.2. Properties of neuronal precursors located in the VZ are determined by the characteristic expression patterns of these transcription factors, leading to the generation of distinct classes of neurons. Recent studies demonstrated that radial glial cells produce neurons in addition to glia during central nervous system development. Thus, neuronal precursor diversity may be dependent upon the diversity of radial glial cells. To investigate this hypothesis, we analyzed the expression of radial glial cell markers and transcription factors in the mouse embryonic spinal cord. We show that radial glial cells indeed express domain-specific transcription factor. Moreover, they varied in expression of the astrocyte-specific glutamate transporter. The region where the astrocyte-specific glutamate transporter is strongly expressed in the ventral radial glial cells is closely related to the Pax6-expressing domain, and the weakly expressing region corresponding to the Nkx2.2-expressing domain. Furthermore, dorsal radial fibers expressed ephrin-B1. Thus, different types of radial glial cells exist in different domains defined by the transcription factor expression at E12.5. We also show that this diversity continues to the gliogenic stage of radial glial cells. This raises the idea that astrocytes generated from different domains along the dorsoventral axis in the mouse spinal cord have distinct characteristics., (Copyright (c) 2005 S. Karger AG, Basel.)

A novel optical scheme for a phase shifting method of Fourier domain optical coherence tomography is presented. With this method we avoid a mechanical scan for phase shifting (mechanical M-scan) by using a reference beam with tilted wavefront. The principle of this system is confirmed with a simple mirror object. This method is applied on a biological sample and used to investigate a porcine anterior eye chamber.

We screened for factors upregulating glial fibrillary acidic protein (GFAP) promoter activity by functional cloning with an immature astrocyte cell line (HB108-10) harboring a GFAP-lacZ construct. One cDNA clone that repeatedly upregulated lacZ expression encoded cystatin C (CysC), a cysteine protease inhibitor. TGF-beta induced CysC and GFAP expression in AP-16 cells, an astrocyte progenitor-like cell line expressing GLAST (a glutamate transporter subtype specifically expressed in immature astrocytes). CysC gene expression started earlier than that of GFAP in the mouse forebrain. It started in the ventricular zone at a similar period as (or slightly after) GLAST expression, but before GFAP expression. Although previous data showed that CysC is involved in the maintenance of adult neural stem cells, our data indicate that it is involved in astrocyte differentiation during mouse brain development., (2004 S. Karger AG, Basel)

Drosophila glial cells missing (gcm) is a key gene that determines the fate of stem cells within the nervous system. Two mouse gcm homologs have been identified, but their function in the nervous system remains to be elucidated. To investigate their function, we constructed retroviral vectors harboring Drosophila gcm and two mouse Gcm genes. Expression of these genes appeared to influence fibroblast features. In particular, mouse Gcm1 induced the expression of astrocyte-specific Ca(2+)-binding protein, S100beta, in those cells. Introduction of the mouse Gcm1 gene in cultured cells from embryonic brains resulted in the induction of an astrocyte lineage. This effect was also observed by in utero injection of retrovirus harboring mouse Gcm1 into the embryonic brain. However, cultures from mouse Gcm1-deficient mouse brains did not exhibit significant reductions in the number of astrocytes. Furthermore, in situ hybridization analysis of mouse Gcm1 mRNA revealed distinct patterns of expression in comparison with other well-known glial markers. The mammalian homolog of Drosophila gcm, mouse Gcm1, exhibits the potential to induce gliogenesis, but may function in the generation of a minor subpopulation of glial cells.

Moloney murine leukemia retroviral vectors are more suitable as tools for gene delivery in vivo in comparison to other vectors due to their stable expression and absence of cytotoxicity. However, because of their low titers and poor proliferation rate in the adult nervous system, the application of retroviral vectors to the nervous system has been limited. To overcome this disadvantage, we have attempted to achieve higher viral titers and apply them to the embryonic mouse brain. By utilizing our improved packaging cell line and concentrating the viral supernatant by the low-speed centrifugation method, we have successfully increased the retroviral titer up to 10(12) cfu/ml. This titer is over 10(6)-fold greater than routinely achieved retroviral titers, and is comparable to, or even higher than, those of adenoviral vectors. We investigated the efficacy of gene transfer into the nervous system, which has thus far proven quite recalcitrant to genetic transfer by characteristically low retroviral titers. Using our retroviral preparation, we have demonstrated the highly efficient delivery and long-term expression of a foreign gene into neural cells both in vitro and in vivo. Moreover, we demonstrated that predominant gene delivery into the neurons of one cortical layer can be achieved by choosing an appropriate date of retroviral infection., (Copyright 2003 S. Karger AG, Basel)

A non-axial-scanning confocal microscope employing a monochromatic light source has been developed. The system controls the defocus of an objective into three to .ve optimized states by using a membrane-adaptive mirror, and determines the axial height of an object according to the confocal output value with each defocus. A genetic algorithm is employed to optimize the adaptive mirror shape, with the information entropy of the spectrum of the lateral confocal spot pro.le used as a cost function in the genetic algorithm. Our experimental system successfully determined axial object height within 50 microm range with 0.64 % of error.

We propose a high-speed, parallel system for lens aberration measurement employing a confocal optical setup. This method uses a non-interferometric, conventional confocal axial response to determine the spherical aberration coefficient of a confocal objective. The aberration coefficients are successfully calculated from the intensity axial response by employing a neural network. It is estimated that the system can find out the aberration coefficients of 10,000 microlenses in 20 seconds of measurement and 1 second of calculation time. Our experimental results also demonstrate the practicality of this system.

A high-speed, all optical coherence tomography system was designed and constructed. This tomography system employs spectral interferometry and optical Fourier transformation to reduce the number of mechanical scanning dimensions required for multidimensional profilometry. The system also employs a time gate comprising a beta -barium borate crystal driven by a femtosecond laser pulse to improve measurement time. This system has 43-mum depth resolution and 150-fs temporal resolution and is capable of taking 1000 cross-sectional image frames per second.

We have developed a spectral interferometric optical coherence tomography (OCT) system with polarization sensitivity that is able to measure a two-dimensional tomographic image by means of one-dimensional mechanical scanning. Our system, which has an axial resolution of 32 mum , calculates the distribution of each element of the Müller matrix of a measured object from 16 OCT images. The OCT system successfully reveals the birefringent nature of human skin tissue.

A new signal-processing technique is proposed that involves a phase-resolved correlation method that one can use to determine the phase distribution of low-coherence interferograms. This method improves the sensitivity and resolution of low-coherence interferometers. The depth structure of an aluminum oxide-coated aluminum mirror was determined by use of a low-coherence interferometer with this method. Three signal peaks were successfully extracted from a noisy interferogram.

Hand-arm vibration syndrome (HAVS) is primarily a disorder of the fingers and hands. However, in some cases, vibration-exposed workers are observed to have also episodic blanching of the hands and feet. In latter cases, arteriographies of both the upper and lower extremities are necessary to diagnose the background arterial disorders. In this study, eight HAVS subjects with such disorders were examined by arteriography for differential diagnosis in cases of workers' accident compensation. In three HAVS cases with thromboangiitis obliterans, the arteriographic examination revealed obstructive changes in the palm and forearm as well as three below-knee lesions in the lower extremities. In five HAVS cases with arteriosclerosis obliterans, obstruction kinking or coiling, stenosis and/or tapering-off of the proper digital arteries were observed together with two below-knee lesions and three high lesions in the lower extremities. From the viewpoint of occupational health, palpation of superficial arteries of both the upper and lower extremities should be routinely performed during both pre-placement and periodic medical examinations for workers exposed to vibrating tools for early detection and/or prevention of any worsening of the background disorders.

Halitosis, defined as unpleasant oral odor, is a concern among the general public. Halitosis is generally diagnosed by organoleptic examination and by gas chromatographic analysis of the main source of halitosis, volatile sulfur compounds, such as hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. Gas chromatography requires a large-scale system and a long running time. We investigated the use of a zinc-oxide thin film semiconductor sensor for measuring trace volatile sulfur compounds in mouth air. Mouth air samples collected in teflon bags from 21 volunteers were analyzed by 3 methods: the monitor analysis, gas chromatography, and organoleptic examination by 3 judges. The readings of the monitor were correlated with the values of the total volatile sulfur compounds measured by gas chromatography (r = 0.75, P < 0.01) and also with the organoleptic scores given by the judges (r = 0.76, P < 0.01). The organoleptic scores were correlated with the gas chromatographic values (r = 0.71, P < 0.01). These results suggest that this new monitor with a zinc-oxide thin film semiconductor sensor may be used for the diagnosis of halitosis. Its small size and simplicity of handling may enable its use for routine chair-side study and field surveys of halitosis.

Two hundred and ninety-four vibration-exposed workers were examined for vibration disease (VD) for the worker's accident compensation. Most subjects were male. Their ages ranged from 24 to 68 years. Duration of vibration exposure ranged from 3 to 30 years. After acclimatization at 25 degrees C to 27 degrees C for at least an hour, the nailfold capillaries of the ring (or middle) finger were studied with a light microscope. A cold water immersion test (5 degrees C, 10 min) was then performed. The morphological findings of the nailfold capillaries were classified based on the criteria by Fagrell & Lundberg. A hundred and eighty subjects were diagnosed as VD and 75 as non VD, even without taking the capillaroscopic findings into consideration. The classification of the capillarograms retrospectively investigated were as follows, i.e. in 98 VD subjects 40 cases were stage A, 42 stage B, and 16 cases stage C. In 26 nonVD subjects 13 cases were stage A, 10 stage B, and 3 cases stage C, respectively. When the borderline of VD and nonVD existed between stage A and stages B and C, the sensitivity was 59.2%, specificity was 50.0%, and false positive and negative were 50.0% and 40.8%. Relationship between the capillary stage and recovery (%) of the skin temperature during the cold water immersion test was also studied. The recovery in stage C was not always lower than that in stage A. Among them, arteriography was performed in 57 cases. Despite the use of vasodilator, markedly delayed perfusion of the finger tips was observed in 28 cases. Their capillary stages were A in 12 cases, B in 11 and C in 3. The peripheral microcirculatory state in VD should be carefully evaluated in combination with appropriately selected examinations, including finger nailfold capillaroscopy.

Halitosis, defined as an unpleasant oral odor, has become a health concern among the general public. The objective of this study was to evaluate the diversity of clinical characteristics of halitosis of the patients who visited dental clinics. Sixty-eight patients with primary complaints of halitosis and 19 patients with primary complaints of periodontal diseases but secondary complaints of halitosis were studied by organoleptic examination. The patients with primary complaints were diagnosed as having halitosis in fewer cases than the patients with secondary complaints-25% and 53%, respectively. Patient complaints for halitosis were further categorized, by questionnaire, into three types: Type 1, self-conscious; Type 2, conscious by the indication of others; and Type 3, conscious by presumptions from the attitude of others. Although 80% of the patients of both groups were of Type 1, only 24.1% of the Type 1 patients with primary complaint, in comparison with 50% of the Type 1 patients with secondary complaint, were actually found to have halitosis. The results suggest that the majority of patients with primary complaints of halitosis at the dental clinic did not actually have halitosis, but suffered from an imaginary halitosis due to presumptions based upon others' attitudes. After treatment, these patients were more likely to be dissatisfied than patients who had visited the clinic with halitosis as their secondary complaint.

Among 330 vibration-exposed workers, 24 cases of hypothenar hammer syndrome in 29 hands were diagnosed by arteriography. The right hand was involved in 13, the left hand in six, and both hands in five cases. The mean age was 55 years, mean duration of vibration exposure 19.4 years, and mean duration of episodic Raynaud's phenomenon 6.4 years. The vascular lesions of the ulnar arteries were classified into three major types with subtypes. Type 1: stenosis of the superficial palmar arch around the hook of the hamate. Type 2a: occlusion of the superficial palmar arch around the hook of the hamate. Type 2b: occlusion of both superficial and deep palmar arches around the hook of the hamate. Type 3a: occlusion of the ulnar artery at the proximal part of the wrist. Type 3b: occlusion of the ulnar artery near the wrist with the occlusion of the dorsal carpal branch of the ulnar artery.

A composite thermoluminescent dosimeter (TLD), composed of four, thin TL elements with a high-speed reader, has been developed by employing an optical-heating method. Each TL element, which is 15 mg/cm2 thick with a 3 mm dia., is prepared by applying Li2B4O7:Cu or CaSO4:Tm to a plastic substrate 14 mg/cm2 thick. Each element can be heated to 350 degree C within 0.8 sec. by IR radiation from a tungsten lamp. The characteristics of this TLD system include the following: (1) the detection limit of the Li2B4O7:Cu is 3 mR and the limit for CaSO4:Tm is 0.1 mR; (2) the energy-dependence curves are similar to the dose-equivalent curve, showing slight under-responses by 15% near 70 KeV for Li2B4O7:Cu and over-responses by 50% at high energies for CaSO4:Tm; (3) despite quick heating, the residual dose is as low as 0.1% of the last exposure signal; (4) responses are very stable for more than 1,000 cycles of repeated exposure readings; (5) no false signal could be detected, even in the cases of sweat or soil contamination; (6) the thin Li2B4O7;Cu element can be used for skin dose monitoring; and (7) the processing time of the automatic reader for the composite dosimeter is 3 hr/500 dosimeters. This TLD system can be applied to personnel dosimetry, gate monitoring and environmental monitoring.