A cost-effective autofluorescence detecting system has been developed by our research group to diagnose and localize the early gastrointestinal cancer, which is occult to the traditional means of detection, for example, biopsy. At the early stage, we utilize autofluorescence spectrum detected by OMA (Optical Multichannel Analyzer) to discriminate cancerous tissue. Although this method can effectively distinguish tumors from normal tissues, it is not suitable to be applied in clinic use due to the high cost of the- most-often used OMA-autofluorescence detector. Then we designed a novel Double PMTs (Photomultiply Tube) system, which consists of two parallel-working A/Ds with lower frequency of acquisition, to replace the OMA system, and the results of clinic experiments prove that it can effectively determine gastrointestinal cancers.

In this paper, we present a general approach to obtain the x-ray projections in cone-beam tomography in order to get rid of random factors in the measurement so as to support proceeding three dimensional (3D) reconstruction. First, the phantom is discretized into cubic volume through inverse transformation, then a generalized projection procedure is proposed to the digitized result without concerning what the phantom exactly be. In the second step line integrals are calculated to obtain the projection of each x-ray through accumulation of tri-linear interpolation. Considering projection angles, a rotation matrix is proposed to the x- ray source and the detector plane so we can get projections in arbitrary angles. In this approach the algorithm is easy to be extended and irregular objects can also be processed. The algorithm is implemented in Visual C++ and experiments with different models show satisfactory experimental results.

The laser acupuncture stimulation has been applied extensively to replace the acupuncture needles. But the laser is transmitted to the acupoint through the skin, so the curative effect of the laser irradiation on an acupoint from cuticle is limited. We have developed the deep laser acupuncture stimulator of modulation and multibeam. The laser beam (such as He-Ne, LD, etc.) is turned into the modulated waveform. The modulated laser beam can simulate the customary acupuncture way such as twirling and rotating, etc. The laser beam is split into 3-8 beams by the means of optical shunt. After that they enter into laser acupuncture pins separately through the optical fiber joiners. The laser beam and pins can give simultaneously the stimulation in the depths of 3-8 acupoints. It has been proved by the clinical practice that the deep laser acupuncture has the notable efficiency for the apoplexy and sequelae of apoplexy, sciatica, rheumatoid arthritis, etc.

The potential application of near-infrared spectroscopic imaging technologies in the field of medical diagnosis for observing the sweat distribution on the skin was considered, which is based on the absorption characteristics of water to light energy at the wavelength of 1.94 micrometers . This is an approach on applications of optical sensing technologies and visual technologies of information processing in the sweat distribution detection. Recently we developed such an optical sensing system to investigate the feasibility of measuring sweat distribution on the skin. We gave a direct function expression related to the water or sweat content and the gray level of the image. We demonstrate the configuration of our system and give an experimental evaluation of the light absorption coefficient of water. Using this system we actually measured the sweat distribution on the face in order to evaluate the effectiveness of this sensing technology applied in the field of medical diagnosis. Several measured results are presented and discussed.

In recent studies, near-infrared spectroscopy (NIRS) has been considered as a potentially ideal noninvasive technique for the postoperative monitoring of plastic surgery. In this study, free flaps were raised on rhesus monkeys' forearms and oxygen delivery to these flaps was monitored following vascular occlusions and inhalation of pure oxygen. Optical fibers were adopted in the probe of the oximeter so that the detection could be performed in reflectance mode. The distance between emitter and detector can be adjusted easily to achieve the best efficacy. Different and repeatable patterns of changes were measured following vascular occlusions (arterial occlusion, venous occlusion and total occlusion) on flaps. It is clear that the near-infrared spectroscopy is capable of postoperatively monitoring vascular problems in flaps. NIRS showed high sensitivity to detect the dynamic changes in flaps induced by inhalation of pure oxygen in this study. The experimental results indicated that it was potential to assess tissue viability utilizing the dynamic changes induced by a noninvasive stimulation. It may be a new assessing method that is rapid, little influenced by other factors and brings less discomfort to patients.

The fluorescence spectrum and decay characteristics of normal and cancerous cells are measured and compared using a time-correlated single-photon counting system in this paper. Furthermore, the measurements of fluorescence decay characteristics at different locations inside the cells are performed by same method. The results obtained can be used as an important basis for cancer diagnosis.

Radiolabeled bioactive peptides which bind specifically to surface receptors over expressed in tumor cells are considered as alternatives for tumor detection with ECT. In this investigation, ^99mTc-hydrazinonicotinyl - TNF analogs (WH701) was labeled using ethylenediaminediacetic acid (EDDA) as coligand (a number of TNF analogs had been selected and synthesized using random phage-display peptides library in our lab) and Pharmacokinetics and feasibility studies were performed.

Atherosclerotic coronary heart disease (CHD) is one of the commonest diseases that is heavily hazardous to people's health. Wall motion abnormalities of L.V. due to myocardia ischeamia caused by coronary atherosclerosis is a significant feature of CHD. This paper was designed to build up a foundation for automatic detection of L.V. contours according to the features of L.V. cineangiograms, for a further study of L.V. wall motion abnormalities. An algorithm that based on morphology for L.V. contours extracting was developed in this paper. As we know morphology is a kind of technique based upon set theory and it can be used for binary image and gray image processing. The principle and the geometrical meaning of morphological boundary detecting for image were discussed in this paper, and the selection of structuring element was analyzed. Comparison was made between morphological boundary detecting and traditional boundary detecting method, conclusion that morphological boundary detecting method has better compatibility and anti-interference capability was reached.

An auxin/IAA induced in vivo green fluorescent protein (GFP) in a living plant Arabidopsis root has been studied by a scanning near-field microscope in transmission mode. The promising near-field images of the inducible GFPs at sub- surface of a plant cell suggest that they may locate proximity to the cell wall, i.e. both sides of and in the cytoplasm membrane. The clear and faint fluorescent spots with 1-3 micrometers showed that the proteins localized nearer and farther to the cell wall, respectively. All GFP molecules gathered together in a cell, and no individual GFP was observed in the experiment.

Photodynamic therapy (PDT), a cancer treatment using a photosensitizer and visible light has been applied to treatment of blood cancer-leukemia. The effect of PDT may be modulated by the leukemia cell type; the photosensitizer's type, dose, dose rate changes; the incubation time; the light wavelength, dosage, dose rate change; the conjugation of photosensitizers to variety subcellular target: cell membrane, mitochondia, lipoprotein or liposome; the addition of chemotherapeutic agents et al. Many reports in the current literature are confusing and often apparently contradictory. In this article, we have attempted to conduct and present a comprehensive review of this rapidly expanding novel field in a range of photosensitizers. Cell types, photosensitizers, treatment conditions and mechanism of PDT are considered. Nonetheless, there is ample ground for optimism, and such knowledge as we already have should effectively underpin the clinical research that is ongoing.

The aim was to characterize the transport of fluorescein isothiocyanate (FITC)-labeled dextran and insulin with different resoluble compounds for peptides and proteins through buccal mucosa. The penetration rate of insulin molecules through porcine buccal mucosa (a nonkeratinized epithelium, comparable to human buccal mucosa) was investigated by measuring transbuccal fluxes and by analyzing the distribution of the fluorescent probe in the rabbit buccal mucosa epithelium, using confocal laser scanning microscopy for visualizing permeation pathways. The confocal images of the distribution pattern of FITC-dextran and FITC-insulin showed that the paracellular route is the major pathway of FITC-dextran through buccal mucosa epithelium, the intra-cellular route is the major pathway of FITC-insulin through buccal mucosa epithelium. The permeation rate can be increased by co-administration of soybean phosphatidylcholine (SPC).

The photochromic retinal protein bacteriorhodopsin (BR) is found in the cell membrane of Halobacterium salinarium. It is the key protein for photosynthetic growth of H.salinarium. BR shows an exceptional stability towards chemical, thermal, and photochemical degradation. The photochromic properties of Bacteriorhodopsin provide the possibility of application in optical information storage. Photoexcition of the O-state of BR, which has an all-trans confirmation, leads to a state with 9-cis configuration, which is thermally stable. The 9-cis containing photoproduct of the O-state was named P-state. It absorbs at 490 nm and can be photochemically reconverted to the initial state. We propose a system of optical information storage in a BR polymer film, which is a reversible optical data recording material and can be rewritten over 10⁶ times without degradation of the film. A three-wavelength EDRAW (Erase Direct Read After Write) experiment was performed. The photoexcited P(490) state shows a permanent storage property confirmed by our contrast ratio experiments. The result of long-term information storage in BR films more than 1 year is obtained.

Based on the micron precision manipulation and measurement in the optical tweezers, we built an optical-trap system that can make quantitative measurement of displacement with nanometer resolution in millisecond time scale and then we can measure the piconewton force involved in the process. It is an eminent tool for manipulating biological specimens at the macromolecular level. In this paper we describe its technical properties, design, and make some discussion.

Immunotherapy has been used for cancer treatment in the past century. Although different approaches have been attempted, the basic strategy has been targeting specific tumor antigens to induce host immune responses. Laser immunotherapy is a novel approach in treating metastatic tumors. The combination of two major interactions in laser immunotherapy - selective photothermal and photoimmunological interactions - is designed to induce a tumor-specific host immune response. The hypothetical mechanism is as follows. The intratumor injection of laser- absorbing dye and the noninvasive irradiation of a near- infrared laser produce an acute, selective thermal tumor killing, and at the same time, release tumor antigens. The in-situ immunoadjuvant then combines with the liberated tumor antigens to stimulate and direct the host immune system to fight against remaining tumor cells both locally and in remote metastatic sites. In effect, an in-situ vaccination against the tumor was achieved. Such an immune response eventually leads to a systemic, long-term tumor resistance. Our pre-clinical animal studies have demonstrated such a long-term immunity. Specifically, a novel immunoadjuvant, glycated chitosan (GC), was used in laser immunotherapy. Because the use of immunoadjuvant is crucial in cancer immunotherapy, the role of GC was investigated.

A number of studies have demonstrated that perturbed cellular calcium homeostasis has been implicated in apoptosis. Some studies showed that selenium compounds were able to induce cell apoptosis. The main objective of this study is to evaluate effect of Na₂SeO₃ on intracellular Ca²⁺ levels in SW480 human colonic carcinoma cells. When SW480 cells were exposed to 25 to 100 micrometers ol/L Na₂SeO₃, we also found that Na₂SeO₃ was able to induce [Ca²⁺]_i, disruption of mitochondrial membrane potential ((Delta) (psi) m) in SW480 cells by using a confocal laser scanning microscope. Ca²⁺ channel inhibitor CoCl₂ and an intracellular Ca²⁺ chelator BAPTA completely inhibited [Ca²⁺]_i increase. CoCl₂, BAPTA and ruthenium red also inhibited disruption of (Delta) (psi) m. The results suggest that Na₂SeO₃ is able to increase [Ca²⁺]_i mitochondria permeability transition and Ca²⁺ is from extracellular Ca²⁺.

At present, the easiest and most effective strategy of imaging functional architecture is based on the slow intrinsic changes in the optical properties of active brain tissue, permitting visualization of active cortical regions at a spatial resolution better than 50 micrometers . This can be accomplished without some of the problems associated with the use of extrinsic probes. Monitoring the spatio-temporal characteristics of cerebral blood flow (CBF) is crucial for studying the normal and pathological conditions of brain metabolism. Laser dynamic speckle imaging technique achieves this goal without the need for scanning by utilizing the spatial statistics of time-integrated speckle, which was first proposed by Fercher and Briers in the early eighties. Considering similarity of these two experimental systems, we are trying to integrate them into one system in order to acquire much more neurophysiological information simultaneously.

In order to fit the different clinical needs for processing special images from variety of imaging modalities (US, MRI, NM), the PACS viewer should have been developed respectively. In this paper we present a modern object- oriented component object model (COM) technology to develop PACS viewer. The application is split into framework and components based on functionality. They can be developed independently and reused in different systems. According to different usage, we can assemble the application by integrating different pre-built reusable components seamlessly into the framework. Due to the open architecture of application, its functions can be extended. PACS viewer will be custom designed as required using this reusable technology that will optimize cost, final design and speed up the development.

Diffuse Optical Tomography (DOT) is a typical inverse problem that aims to retrieve internal chromophore distributions noninvasively. Algebraic Reconstructions Techniques (ART) are one of the popular image reconstruction techniques used in DOT. We investigate in this report the influence of the order in which data are accessed in ART. Simulations mimicking breast tissues in transmission geometry with contrast agent tumor enhancement were used to evaluate the image quality of the diverse projection access investigated. We show that by selecting proper projection access order, the convergence speed can be significantly improved when ART is used to perform DOT. Moreover, low- contrast detection is improved.

Native fluorescence spectral characteristics of red blood cells were studied in the visible region in this paper. Blood samples were collected from normal small albino rats. Native fluorescence spectra of the erythrocyte were induced using Light Emitting Diode (LED) at yellow wavelength about 570+/- 16 nm ((Delta) (lambda) _0.5approximately equals 32nm). As the rat's erythrocyte content of in physiological water is increasing, the fluorescent primary emission peak is red shifted from 588 nm to above 615 nm. Furthermore, the fluorescence intensity at about 600 nm was found to be maximal while the rat's erythrocyte consistence is 1%. Moreover, it is shown in large numbers of experiments that LED-induced fluorescence spectra of the erythrocyte are similar with the whole blood. It may make sense for low- intensity light therapy.

In laser surgery, it has been observed pulsed 532-nm laser can avoid postoperative purpura, but pulsed 585-nm, 595-nm or 600-nm lasers nonetheless cause purpura when they were used to treat port-wine stains; the XeCl excimer laser (308 nm) can safely and effectively clear psoriasis; both XeCl excimer laser and Ho:YAG laser were used in coronary interventions, but only former was approved by the FDA; open channels after ultraviolet (UV) laser treatment and closed channels with infrared (IR) lasers for transmyocardial laser revascularization; and so on. In this paper, the biological information model of low intensity laser (BIML) is extended to include UVA biomodulation and is used to understand these phenomena. Although the central intensity of the laser beam is so intense that it destroys the tissue, the edge intensity is so low that it can induce biomodulation. Our investigation showed that biomodulation of light on cells might play an important role in the long-term effects of laser surgery.

Color indirect effect (CIE) is referred to as the physiological and psychological effects of color resulting from color vision. In previous papers, we have studied CIE from the viewpoints of the integrated western and Chinese traditional medicine, put forward the color-autonomic- nervous-subsystem model (CAM), and provided its time-theory foundation. In this paper, we applied it to study light effects on melatonin regulation in humans, and suggested that it is CIE that mediates light effects on melatonin suppression.

This paper applied the zero-crossings of laser speckle (ZCLS) method, utilizing the diffraction of a focused Gaussian beam, to obtain the dynamics of lymph flow on the rat mesentery in vivo. Two experiments were designed in this study: one was the intralipid model experiment; and the other was the lymph flow under the influence of isoprenaline. In the former, the temporal dynamics of intralipid flow were acquired indicating the validity of the ZCLS method. In the latter, the speckle interferometry results manifested no significant changes in the average velocities of lymph flow, which was consistent with the result obtained by the conventional physiological method of frame by frame analysis. However, the speckle results also manifested that the lymph flow dynamics changed under the drug's influence, which could not be gained by the conventional physiological methods. These indicated that the speckle interferometry technique was promising to determine lymph-flow diagnostics.

In previous paper, process-specific times (PSTs) are defined by use of molecular reaction dynamics and time quantum theory established by TCY Liu et al., and the change of PSTs representing two weakly nonlinearly coupled bio-processes are shown to be parallel, which is called time parallel principle (TPP). The PST of a physiological process (PP) is called physiological time (PT). After the PTs of two PPs are compared with their Yin-Yang property of traditional Chinese medicine (TCM), the PST model of Yin and Yang (YPTM) was put forward: for two related processes, the process of small PST is Yin, and the other process is Yang. The Yin-Yang parallel principle (YPP) was put forward in terms of YPTM and TPP, which is the fundamental principle of TCM. In this paper, we apply it to study TCM on the effects of low intensity laser on cells, and successfully explained observed phenomena.

Neuroimaging has played an important role in evaluating the Alzheimer's disease (AD) patients, and its uses are growing. Magnetic resonance imaging (MRI) may show the presence of cerebral infarcts and white matter disease. Single photon emission computed tomography (SPECT) and positron emission tomography (PET), which visualize such cerebral functions as glucose metabolism and blood flow, may provide positive evidence to support the diagnosis of AD. Electrical impedance tomography (EIT) is a recently developed technique which enables the internal impedance of an object to be imaged noninvasively.

An experimental study of controlling the optical properties of in vitro and in vivo rabbit dura mater with administration of osmotical agents, 40% glucose solution and glycerol, using video camera and spectrometer was presented. The preliminary results of experimental study of influence of osmotical liquids (glucose solutions, glycerol) on transmittance (in vitro) and reflectance (in vivo) spectra of rabbit dura mater were reported. The significant decreasing of the reflectance and increasing of the transmittance of dura mater under action of osmotical solutions were demonstrated. Experiments showed that administration of osmolytes to dura mater allowed for effective and temporary control of its optical characteristics, which made dura mater more transparent, increased the ability of light penetrating the tissue, and consequently improved the optical imaging depth. It is a significant study, which can improve penetration of optical imaging of cerebral function and acquire more information of the deep brain tissue.

The dynamic bio-speckle, which is formed when the plant seed is irradiated by laser, carries the biology information of the seed. The statistic properties of bio-speckle are related to the physical state of the seed and the illumination conditions, whose varieties will lead to the change of bio-speckle. In this paper, we observe the change of the plant seed's dynamic bio-speckle in various conditions.

Low level He-Ne laser irradiation (e.g., intravascular laser irradiation on blood, ILIB) has been widely used to treat some illness clinically. One of the action processing is by improving immunocompetence of the body, but the mechanism is still not clear. In this paper, we used mouse macrophages as study object for real-time observation of the concentration change of intracellular free calcium (abb. as [Ca²⁺]_i) of macrophages and the distribution of the Ca²⁺ using LSCM (laser scanning confocal microscope) after irradiation with different dose low level He-Ne laser (the actual irradiation power (abb. as P) is 0.16 mw and the facular diameter (abb. as D) is 0.5 cm. We found interesting phenomena through the image of [Ca²⁺]_i of macrophages. The distribution of Ca²⁺ in macrophages has no obvious change when the time of irradiation (abb. as T_i) is 10 min. The [Ca²⁺]_i shows obvious increase and a concentrate phenomena in Ca²⁺ distribution appears when T_i reach 20 min. The change of the distribution of Ca²⁺ become more distinct: [Ca²⁺]_i increase more visibly and the distribution of Ca²⁺ shows a spacial grads when T_i reach 30 min.

In this study, by chemiluminescence method using a Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7- dihydroimidazo[1,2-a]pyrazin-3-one (MCLA), as a selective and sensitive chemiluminescence probe, singlet oxygen (¹O₂) formation was observed in the vit C- LDL-Cu²⁺ reaction system. Another experimental evidence for the generation of ¹O₂ was the quenching effect of sodium azide (NaN₃) on vit C-induced chemiluminescence in the reaction mixture of LDL- Cu²⁺-MCLA. Analysis based on the experimental results indicated the plausible reaction mechanism is that vit C converts Cu²⁺ to its reduced state and vit C becomes vit C radical itself, thereby stimulating the formation of peroxyl radicals, and bimolecular reaction of peroxyl radicals results in ¹O₂ production in the above systems.

Ultraweak Chemiluminescence (UCL) studies of different aging degree of rice (Oryza sativa L.) seeds stored in a high temperature 40 degree(s)C and high relative humidity 90% environment (0 day, 8 days, 15 days, and 22 days) were carried out. We firstly observed that aging degree of rice seeds was positive correlation with ultraweak chemiluminescence during the early imbibition (0-1h). Addition of water to rice seeds stimulates ultraweak chemiluminescence, the intensity of which depends upon aging degree of seeds. The shorter the seed accelerated aging time was, the higher the intensity of the UCL in the early imbibition period, the lower hydrogen peroxide (H₂O₂) concentration of rice seeds, the higher percentage seed germination. The germination and superoxide dismutase (SOD) activity of dry rice seeds was obvious positive correlation with the intensity of UCL. While catalase (CAT) activity of rice seeds was determined. Mechanism of ultraweak chemiluminescence was discussed. It was concluded that the store time of rice seeds could be judged from their UCL characters during the early imbibition period, which might be a way to examine vigor of seeds.

Near-infrared spectroscopy (NIRS) is a focus of attention in the research field of biomedical photonics. The concentration of HbO₂ in human skeletal muscle has been measured noninvasive NIRS using a portable tissue oximeter continuously when the subjects did incremental exercises on a power bicycle. Blood lactate is one of traditional physical research subjects which is applied most widely. We study blood volume in the tissue of sportsmen when they are subjected by the incremental physical load, simultaneously detecting some parameters such as the heart rate, maximal oxygen absorption and the concentration of blood lactate. As the intensity of exercises was heightened, the concentration of blood lactate and blood volume in tissue increased, while the concentration of HbO₂ decreased. Thus the rudimental characteristics of energy consumption and supply during hypoxia and aerobic exercises are investigated. By discovering the relationship between blood lactate in human skeletal muscle and blood oxygenation, a novel approach for measuring blood lactate noninvasively and assessing the sports ability could be provided. Furthermore, it is possible to assess the fatigue state with tissue oximeter to monitor the human sports intensity noninvasively and dynamically.

In-phase and Quadrature Phase Detection System (I&Q System) can be used to detect the clinic-related parameters such as hemoglobin concentration and saturation. We set up an effective multi-wavelength fitting model and method to calibrate the tissue optical properties such as the reduced scattering factor ((mu) _s) and the absorption factor ((mu) _a), which can be calculated from the measured amplitude and phase shift of I&Q system. Then using the calibrated tissue optical parameters, we can get better results for hemoglobin concentration and saturation by our proposed algorithm of fitting multi-wavelength absorption coefficient ((mu) _a) of the medium than those from the previous I&Q system based on the two-wavelength absorption coefficient calculation. Our algorithm is used in the clinical experiments with five wavelengths (680 nm, 750 nm, 780 nm, 810 nm, 830 nm) for the necks' and arms' saturation test between normal persons and tumor-bearing patients.

Diffuse Optical Tomography (DOT) in the Near Infrared Spectral window (NIR) offers new possibilities for medical imaging. And using DOT, Indocyanine green (ICG) is found to be a useful blood pooling contrast agent for optical tumor detection. Here we introduce our efforts on study of breast cancer image reconstruction using ICG as a contrast agent. To improve the signal-to-noise ratio, we developed an effective method to analyze and process the raw data acquired from a CWS (Continuous Wave Spectroscopy) system. Differential absorption images of breast cancers are reconstructed by using ART (Algebraic Reconstruction Technique) which uses the diffusion equation within the Rytov approximation. The experiment device is a combination of sixteen light sources (tungsten bulb) and sixteen light detectors (silicon photodiodes). These sources and detectors are located on a circular holder where the human breasts are placed, each other at equal distance (11 angle apart). It takes a few seconds to acquire data since one source is on, while all the detectors simultaneously detect the photons. So an image includes 16*16 data points. Results from clinical trial in Japan and China show that there is a high concentration of ICG in the location of a cancer, suggesting high blood volume pooling and the usefulness of ICG detecting optically breast cancers.

Electrochemiluminescence (ECL) technique for bimolecular detection offers ultra-high sensitivity and good signal-to- noise ratio. In this work, an ECL reaction and detection system were established. We used a big working electrode and a single photon counter to heighten the detection limit. The results showed that the detection limit of the system is 1/1000 fmol/L free labeled Ru(bpy)₃ ²⁺. The concentration dependence of ECL intensity was not linear in the range of low concentration (fmol/L level) free labeled Ru(bpy)₃ ²⁺. While in pmol/L level, the ECL intensity was linear. Ru(bpy)₃ ²⁺ + TPA (tripropylmine) ECL reaction system was used to indicate P53 protein from human SWO-38 cell line, which was established from grade 1-11 glioma tumor. This method could have potential applications in early-stage tumor diagnosis and environmental inspection.

The characteristics of photoacoustic signals generated in real biological tissues are analyzed in time domain and in frequency domain through experiments. It is found that the frequency ranges of photoacoustic signals generated in fresh porcine fat, muscle, liver and kidney are about 5.0 MHz, 1.5 MHz, 2.0 MHz and 2.0 MHz respectively, and their duration is about 1-4 microsecond(s) . A positive peak is very obvious in the photoacoustic waveform of porcine liver, and a negative peak is sharp in the photoacoustic waveform of porcine fat. The main frequencies of photoacoustic signal are relatively stable, which correspond to the properties of biological tissues. The results obtained here are significant for photoacoustic tomography of biological tissue.

The green fluorescent protein (GFP), from the bioluminescent jellyfish Aequorea victoria, yields a bright green fluorescence when expressed in either eukaryotic or prokaryotic cells and illuminated by blue or UV light. The characteristic properties of GFP make this protein a good candidate for use as a molecular reporter to monitor patterns of protein localization, gene expression, and intracellular protein trafficking in living cells. In this study, the plasmid EGFP encoding GFP was used to transfect SWO cells (a cancer cell line of nerve gelatinous tissue) mediated by liposome: (1) The plasmid EGFP-C1, purchased from Clontech Co., propagated in suitable E. coli strain (JM 109), was extracted by Concert High Purity Plasmid Miniprep (Gibco). (2) SWO was cultured in RPMI 1640 (10% FCS and 25 mM HEPES), 37 degree(s)C, 5% CO₂. Cancer cells were transfected in 6-cm tissue culture dishes by Lipofectin Reagent (Gibco) for 6-12 hr using 2 ug DNA. (3) Then, infected cells were collected in medium containing 800 ug/ml G418, and the resistant clones were harvested and subcloned in fresh culture medium maintaining 800 ug/ml G418. (4) The cells were examined by using Nikon fluorescent microscope (E600) and Bio-Rad confocal microscope (MRC 600). (5) Next step, the cancer cells, stably expressing GFP after in vivo transduction, were implanted by surgical orthotopic implantation (SOI) in nude mice. Tracking of these cancer cells will become more sensitive and rapid than the traditional procedure of histopathological examination or immunohistochemistry. This method demonstrates external, noninvasive, whole-body, real-time fluorescence optical imaging of internally growing tumors and metastases in transplanted animals.

A restoration mathematics model is established for deep layer in multiphoton excitation scanning microscopy by analyzing three-dimensional confocal scanning image attenuation in turbid medium. Furthermore we build the relationship between the attenuation coefficient and scattering coefficient and restore the deep layer images dependent on the relationship. The restored images of pig epidermis in the light of this model are discussed.

Current high-performance computers and advanced image processing capabilities have made the application of three- dimensional visualization objects in biomedical computer tomographic (CT) images facilitate the researches on biomedical engineering greatly. Trying to cooperate with the update technology using Internet, where 3D data are typically stored and processed on powerful servers accessible by using TCP/IP, we should hold the results of the isosurface be applied in medical visualization generally. Furthermore, this project is a future part of PACS system our lab is working on. So in this system we use the 3D file format VRML2.0, which is used through the Web interface for manipulating 3D models. In this program we implemented to generate and modify triangular isosurface meshes by marching cubes algorithm. Then we used OpenGL and MFC techniques to render the isosurface and manipulating voxel data. This software is more adequate visualization of volumetric data. The drawbacks are that 3D image processing on personal computers is rather slow and the set of tools for 3D visualization is limited. However, these limitations have not affected the applicability of this platform for all the tasks needed in elementary experiments in laboratory or data preprocessed.

This paper presents a novel ophthamological optical coherence tomography detecting instrument, which we design, and introduces measuring arm emphatically. For glaucoma which is very common in the Orient, this system can achieve both the eyeground detection and the canthus detection. And it combines the cranny lamp's conventional detection with optical coherence tomography. Considering all the system, this design has a longitudinal resolution of 15 um, and a transverse resolution of 20 um at imaging velocity of 4 frames per second.

Laser speckle system was used to measure thermally induced change in velocity of blood flow inside micrangium of rat's mesentery. Meanwhile, the diameter of blood vessels was measured with pickup camera. Based on these measurements, changes in blood perfusion by heat were deduced. The results indicated that velocity of blood flow depended on temperature when tissue was heated, as well as time.

We discuss how a spectral-domain method in combination with a split-operator technique can be used to calculate exact solutions of the time-dependent Maxwell's equations. We apply this technique to study the propagation of a light pulse through an inhomogeneous medium consisting of multiple random scatterers. We investigate the validity of the Boltzmann equation by directly comparing its solution with the ensemble averaged Maxwell solution.

A frequency domain heterodyne system for recording the amplitude and phase of diffuse photon density wave (DPDW) is described here. We demonstrated experimentally the possibility of tomographic image reconstruction using a pair of out-of-phase sources. Both iterative method (SIRT) and subspace technique (SVD) have been used to address the inverse problem. The image quality with respect to the number of iterations and regularization numbers is discussed. Further investigations including the relationship between several parameters (such as modulation frequency, the source pair separation and the number of source and detectors) and the image quality are also discussed.

An experimental monitoring of tissue modification of in vitro and in vivo rabbit dura mater with administration of osmotical agents, 40% glucose solution and glycerol, using optical coherence tomography was presented. The preliminary results of experimental study of influence of osmotical liquids (glucose solutions, glycerol) of rabbit dura mater were reported. The significant decreasing of the light from surface and increasing of the light from the deep of dura mater under action of osmotical solutions and the increasing of OCT imaging depth were demonstrated. Experiments showed that administration of osmolytes to dura mater allowed for effective and temporary control of its optical characteristics, which made dura mater more transparent, increased the ability of light penetrating the tissue, and consequently improved the optical imaging depth. It is a significant study, which can improve penetration of optical imaging of cerebral function and acquire more information of the deep brain tissue.

Multiphoton excited fluorescence detection is a powerful tool for probing chemistry and structure deep within biological tissue, for performing sensitive measurement on deep-UV (ex 200-300 nm) specimen. We present an approach for rapid analysis of Rhodamine B using multiphoton excited fluorescence detection coupled to capillary electrophoresis separations. In this highly versatile approach, Rhodamine B is excited through the nearly simultaneous absorption of two low-energy photons, fluorescence can be detected efficiently with low background. In these studies, Rhodamine B is fractionated in several minutes, with mass detection limits as low as 10 amol (2nM). This approach is demonstrated to be a powerful tool for analyzing the complex biological samples of minute quantities.

The concept of refractive index matching used to enhance the optical penetration depth of tissue and whole blood is discussed on the basis of in vivo and in vitro studies using the NIR optical spectroscopy and coherence tomography techniques.

Cognitive neuroscience is a science of information processing. Optical techniques are playing more and more important roles in revealing the mechanisms of information processing from different levels of the nervous system. This paper gives an overview of the optical imaging approaches in cognitive neuroscience in our lab. First we introduce optical imaging of neurons with multiphoton excitation laser scanning confocal microscopy, then optical imaging of either cultured neuronal networks or nature neuronal networks with multiphoton microscopic imaging system combined with multi- electrode array, and then several optical imaging systems for intrinsic signal imaging in cortex or brain slices, which include CCD-based optical imaging system, OCT system and laser speckle imaging system. Finally we report our recent results on functional optical imaging of human brain activity.

Green fluorescent protein (GFP) transfected Hela cell was planted in naked mice, to construct an in vivo model for monitoring the therapeutic effect of laser hyperthermia in real time. A cooled CCD fluorescence imaging system was used to record the tumor fluorescence image during the hyperthermia process. Primary experimental results were presented in this paper. To make sure the fluorescent probe GFP does not have strong effect on the biologic function of the host tumor cell (Hela cell), several conventional biological processes were observed in real time. First, neurons, which are much more tender than tumor cells, were transfected with GFP (cameleons). No morphological inhomogenities were observed, and normal functional responses of the neurons were observed when stimulated with histamine. In the second step, the mitosis process of cultured Hela cell was monitored. The features observed during mitosis confirmed that the transfection does not ruin the mitosis process of the tumor cell. At last, naked mice with tumor cell was constructed, which emit fluorescence in the tumor region when excited with faint laser. This presentation provides an in vivo biological model for quick monitoring of the therapeutic results of tumor hyperthermia.

The autofluorescence of 5-Hydroxytryptamine (5-HT) loaded rat mucosal mast cells (RBL-2H3 cells) is imaged with multiphoton excitation laser scanning microscope (MPELSM). 5-HT correlative visible fluorescence (F_co-vis) excited with 740-nm multiphoton excitation is observed in live cells for the first time, and the generating mechanism of 5-HT F_co-vis is studied. The spatial distribution of 5-HT in live cells is imaged at high spatial resolution in our experiment, which provides a new way to study the correlation between 5-HT spatial distribution and content, and the cellular functional state in live tissue or cells.

The continuous light coming from the Argon Gas Ion Laser can be converted to pulse light when an optical chopper is equipped. The sample is excited by the pulse light in the confocal microscopy system. The light intensity of the excitation light and the phosphorescence is simultaneously recorded in terms of gray value by the confocal microscopy system. The phosphorescence lifetime measurement can be realized with time-resolved analysis for the phosphorescence intensity decay. The different decay lifetimes of the Oxy- Phor R2 sample under different oxygen concentration are measured with the reconstructed confocal microscopy system.