This paper overviews recent results on immersion control of optical properties of various tissues and blood. OCT and polarization measurements were taken as advanced examples. It was demonstrated that reflection, transmission and state of polarization of the scattered light by a tissue or blood are effectively controlled by changes of refractive index of the background (blood plasma or tissue interstitial space).

A hand-held polarized light camera yields an image whose contrast is based on photons scattered from the superficial subsurface region of tissues. The general approach toward polarized light imaging is presented, discussing the Stokes Vector description of polarized light and the Mueller Matrix description of the scattering process. The simple approach of the hand-held camera is presented with a first clinical image of melanoma

The influence of low-intensity laser radiation on the transport of human blood within skin capillaries is investigated in vivo on cardiac ischemia patients. For the sample as a whole the mean blood perfusion increased by thirty percent after exposure, for 10 minutes, to light from a Helium Neon laser at an irradiance level of 225 W/m². In some individual patients the blood perfusion more than doubled. A two-dimensional theoretical model is developed that suggests that modest heating of the blood is induced by the incident radiation and could be responsible for the observed increase.

An analytical approach is proposed to treat heat transfer through two-component biological tissues composing of bloodless base and blood vessels under irradiation by a pulse light beam of finite dimensions and arbitrary duration. The approach is based on the optical and thermal tissue model accounting for individual optical characteristics of the above components, heat exchange between them, and convection losses at the interface with any external medium. Under reasonable assumptions, the Green function of the equation set for bloodless tissue and blood is expressed as a product of the corresponding Green function for an infinitely wide beam by a simple radial function determined by the radial shape of the irradiating light. So for any temporal structure of the external radiation, temperature rise of the composite tissue is a single convolution-like integral from analytical functions. This enables us to study explicitly some limiting cases of the heating and cooling. The effects of critical parameters of the problem and asymptotic temperature regimes gain a physically vivid and transparent form. Sample examples of these effects are considered and discussed in the paper.

Immunoadjuvants have been used to stimulate host immune responses. However, immunoadjuvants alone have not been very successful in treating metastatic tumors. Following the principle of combined therapy in AIDS treatment and in combination chemotherapy, immunoadjuvants have been used in conjunction with other treatment modalities. The current study is an attempt to use both selective photothermal and selective photochemical interactions to accompany a new immunoadjuvant in the treatment of metastatic tumors. The immunoadjuvant, glycated chitosan (GC), has been shown in the previous studies to be effective in inducing immune responses when combined with the treatment of laser irradiation after the intratumoral injection of indocyanine green solution. When glycated chitosan was used with photodynamic therapy (PDT), the treatment effect was significantly increased. Specifically, when glycated chitosan was injected peritumorally after Photofrin-based PDT treatment of EMT6 mammary sarcoma in mice, the tumor-free rate of the treated mice was increased from 38% to 75% using 1.5% GC solution. In mTHPC-based PDT treatment of Line-1 lung adenocarcinoma in mice, the tumor-free rates of treated mice reached 38% while PDT alone did not result in any tumor free mouse. The combination of the immunoadjuvant and selective photophysical interaction may become an effective method to treat tumors with an induced anti-tumor immunity.

This paper introduces the optical imaging approaches at three levels in cognitive neuroscience in the Key Laboratory of Biomedical Photonics of Ministry of Education of China. In molecular and cellular level, the advances in microscopy, molecular optical marker, and sample preparations have made possible studies that characterize the form and function of neurons in unprecedented detail. The development of two-photon excitation has enabled fluorescent imaging of small structures in the midst of highly scattering media with little photodamage. The combination of MPE and multi-electrode array provides a powerful approach for neuronal networks imaging. Intrinsic signal imaging (ISI) and laser speckle imaging (LSI) are effective approaches for intrinsic signal imaging at a given cortical site. No alternative imaging technique for the visualization of functional organization in the living brain provides a comparable spatial resolution. It is this level of resolution that reveals where processing is performed - a necessary step for the understanding of the neural code at the population level. Completely noninvasive optical imaging through the intact human skull, such as functional near infrared imaging may provide an imaging tool offering both the spatial and the temporal resolutions required to expand our knowledge of the principles underlying the remarkable performance of the human cerebral cortex.

We investigate the validity of the Boltzmann equation by directly comparing its solution with the ensemble averaged Maxwell solution for a system of randomly arranged plane parallel dielectric layers. We show how the calculation of the usual Boltzmann scattering coefficient from microscopic parameters can be improved to permit a better agreement with the exact Maxwell data.

Photodynamic therapy (PDT) mediated with vascular acting photosensitizer pd-bacteriopheophorbide (Tookad), is investigated as an alternative modality for the total ablation of prostate cancer. In vivo normal canine prostate is used as the animal model. Interstitial PDT was performed by irradiating the surgically exposed prostates with a diode laser (763 nm, 150 mW/cm) to activate the i.v. infused photosensitizer drug. The effects of two-session PDT were evaluated. The prostate and its adjacent tissues were harvested and subjected to histopathological examination. At one-week, post second-session PDT, the animals recovered well with little or no urethral complications. Prostatic urethra and prostate adjacent tissues (bladder and underlying colon) were well preserved. Two-session PDT or one single session PDT induced a similar extent of damage. PDT induced prostate lesions were characterized by marked hemorrhagic necrosis. Maximum lesion size of over 3 cm in dimension could be achieved with a single 1-cm interstitial treatment, suggesting the therapy is very effective in ablating prostatic tissue. Pharmacokinetic studies show that the photosensitizer is cleared rapidly from the circulation. In conclusion, the novel photosensitizer Tookad mediated PDT may provide an effective alternative to treat prostate cancer.

We used single photon emission computed tomography (SPECT) in brain perfusion imaging to study the changes of regional cerebral blood flow (rCBF) and cerebral function in brain infarction patients treated with intravascular laser irradiation of blood (ILIB). 17 of 35 patients with brain infarction were admitted to be treated by ILIB on the base of standard drug therapy, and SPECT brain perfusion imaging was performed before and after ILIB therapy with self-comparison. The results were analyzed in quantity with brain blood flow function change rate (BFCR%) model. Effect of ILIB during the therapy process in the other 18 patients were also observed. In the 18 patients, SPECT indicated an improvement of rCBF (both in focus and in total brain) and cerebral function after a 30 min-ILIB therapy. And the 17 patients showed an enhancement of total brain rCBF and cerebral function after ILIB therapy in comparison with that before, especially for the focus side of the brain. The enhancement for focus itself was extremely obvious with a higher significant difference (P<0.0001). The mirror regions had no significant change (P>0.05). BFCR% of foci was prominently higher than that of mirror regions (P<0.0001). In conclusion, the ILIB therapy can improve rCBF and cerebral function and activate brain cells of patients with brain infarction. The results denote new evidence of ILIB therapy for those patients with cerebral ischemia.

Optical pumping is to use light photons to polarize the atomic electron spins first and then the nuclear spins of noble gases get polarized through the spin exchange between atomic electron spins and nuclear spins. Using optical pumping nuclear spins of noble gases such as ³He and ¹²⁹Xe can be polarized to 50% or higher, hundred thousand times higher than the proton polarization in conventional MRI. It has been found in this theoretical work that the conventional spin relaxation equations are not valid for the hyperpolarized spins. We find that hyperpolarization and spin coupling result in the multipole spin orders. These multipole spin orders cross-relax each other. New longitudinal relaxation equations for the dipole-dipole coupled hyperpolarized spins at room temperature have been derived. These new equations predict that the longitudinal magnetization relaxation of hyperpolarized spins is, in general, bi-exponential decay instead of single exponential decay. The potential applications of the findings in quantifying the paramagnetic source in lung and other tissue and in modeling hyperpolarized spin relaxation in bio-compatible media are pointed out as well.

High performance capillary electrophoresis(HPCE) has been widely applied to the field of chemistry and life science for its advantages of high separation efficiency, short analysis times and low sample volume requirements. But how to improve the detection capability of capillary electrophoresis was ever a key problem. Multi-photon excitation (MPE) fluorescence detection could solve this problem, however this method needed expensive femtosecond mod-locked laser, which restricted the improvement of capillary electrophoresis. In this paper, we implemented a set of MPE-CE system based on a continuous wave (CW), successfully exploited the CW multi-photon excitation to achieve detection of capillary electrophoresis. In our current MPE-CE system we used Ti:sapphire laser to prove MPE-CE could work in CW mode. From this point, we would substitute the laser with laser diode (LD) in future. This is really a new but also practical idea in MPE-CE system based on CW.

The membrane receptor mediated signal transduction mechanism (STM) on photobiomodulation was suggested by Liu et al, and verified by successful applications. In this paper, it was used to study photobiomodulation on fibroblasts. As the frequency of the absorption light of membrane receptors is greater than the light from UVA to IR, the membrane absorption of the light is non-resonant, and its transition rate is extraordinarily small, but can be amplified by the coherent state of the identical and independent membrane receptors. The activation coherent states of receptors will activate signal transduction pathway, which was called collective phototransduction. It was shown that collective phototransduction mediated STM was one of the possible mechanisms of photobiomodulation on fibroblasts.

The numerical phase function calculated with Mie theory is discussed in this paper. 1) The comparison between Mie phase function and Henyey-Greenstein phase function is made. Results show that Mie phase function is of great advantage, specially, in the simulation of polarized light transport in turbid medium. 2) The equivalent phase function of phantom consisting of micro-spheres of different sizes is presented. With this discussion, the differences between numerical phase function, Henyey-Greenstein phase function, and experimental measured phase function are discussed.

Laser acupuncture as an alternative, noninvasive, painless and cost-effective therapy is widely used for acute and chronic pain, nausea, circulatory functions, and mood-related behavioral disorders. It was suggested one of the pathways mediated laser acupuncture was from laser biomodulation on acupuncture point cells to autonomic nervous subsystems through meridian. As laser irradiation used for acupuncture is red or infra red, we put forward the following model: at dose 1(10^0-3 J/m²), the irradiation activates parasympathetic nervous subsystem (PSN); at dose 2(10^3-5 J/m²), the irradiation activates sympathetic nervous subsystem (SN); at dose 3(10^5-6 J/m²), the irradiation activates PSN; and at dose 4(10^6-7 J/m²), the irradiation activates SN. This model was verified by its successful applications.

Exercise-induced fatigue has long been an important field in sports medicine. The electron leak of mitochondrial respiratory chain during the ATP synthesis integrated with proton leak and O^-.2 can decrease the efficiency of ATP synthesis in mitochondria. And the exercise-induced fatigue occur followed by the decrease of performance. If the dysfunction of mitochondria can be avoided, the fatigue during the exercise may be delayed and the performance may be enhanced. Indeed there are some kind of materials can partially prevent the decrease of ATP synthesis efficiency in mitochondria. But the side effects and safety of these materials is still needed to be studied. Low intensity laser can improve the mitochondria function. It is reasonable to consider that low intensity laser therapy may become the new and more effective way to delay or elimination the fatigue induced by dysfunction of mitochondria. Because the effect of laser irradiation may not be controlled exactly when study in vivo, we use electrical stimulation of C2C12 muscle cells in culture to define the effect of low intensity laser on the dysfunction of mitochondria, and to define the optimal laser intensity to prevent the decrease of ATP synthesis efficiency. Our study use the C2C12 muscle cells in culture to define some of the mechanisms involved in the contractile-induced changes of mitochondrial function firstly in sports medicine and may suggest a useful study way to other researchers. We also give a new way to delay or eliminating the fatigue induced by dysfunction of mitochondria without side effect.

Cortical spreading depression (CSD) is an important disease model for migraine and cerebral ischemia. We investigated the spatio-temporal characteristics of the intrinsic optical signals (IOS) at 570 nm and the cerebral blood vessel responses during CSD simultaneously by optical reflectance imaging in vivo. The CSD were induced by pinprick in 10 α-chloralose/urethane anesthetized Sprague-Dawley rats. A four-phasic IOS response was observed at pial arteries and parenchymal sites in all experimental animals and an initial slight pial arteries dilation (21.5%±13.6%) and constriction (-4.2%±3.5%) precedes the dramatic dilation (69.2%±26.1%) of pial arterioles was recorded. Our experimental results show a high correlation (r = 0.89±0.025) between the IOS response and the diameter changes of the cerebral blood vessels during CSD in rats.

Liu TCY et al have suggested the membrane receptor mediated signal transduction mechanism (STM) on photobiomodulation, which was verified by successful applications. In this paper, STM is extended to virus, and called electron excitation. As the frequency of the absorption light of envelope glycoproteins is greater than the one of light from UVA (320-400 nm) to IR, the envelope glycoprotein absorption of the light is non-resonant, and its transition rate is extraordinarily small, but can be amplified by the coherent state of the identical and independent envelope glcyoproteins. We apply VSTM to discuss the possibility that light from UVA to IR is used to inactivate the coronavirus of severe acute respiratory syndrome.

We report our experimental results of in vivo observing x-ray attenuation of intra-tumor injection of indocyanine green (ICG). An eight- to nine-week-old male BALB/c mouse weighting between 15 and 20 g is used in the experiments, which has been implanted with myeloma cell line (SP2/0) two week before. The system used to monitor the intratumor diffusion of ICG is a digital x-ray imaging system. It works at 33kVp, 0.3mAs, 4 seconds and 1.5×magnification. The objective of this research is to study the x-ray attenuation at different area, which represented by gray-scale value. Compare to the ROI in the tissue without ICG and ROI of black background in the image, there is an obvious change before and after injecting ICG in the tumor, which is the area ICG can diffuse to. It shows the feasibility of using digital x-ray imaging system to dynamically, effectively and noninterventionly monitor the diffusion of the ICG.

This paper introduces the algorithm and the basic theory of Independent Component Analysis (ICA), and discusses how to choose the proper ICA model of the data by the characteristics of the underlying signals to be estimated. The Spatial ICA (SICA) is applied to model and analysis of the data in the experiment when the signals and noises are spatially dependent. The data acquired from the intrinsic optical signals which are caused by electricity stimulation to sciatic nerve of rat are analyzed by SICA. In the result, the active-related component of the signals and its time course can be separate, and the signals of heartbeat and respiration also can be separated.

Much research showed that there is phtotobiomodulation on cell apoptosis. The membrane receptor mediated signal transduction mechanism (STM) on photobiomodulation was suggested by Liu et al, and verified by successful applications. In this paper, it was used to study photobiomodulation on cell apoptosis. As the frequency of the absorption light of membrane receptors is greater than the visible light, the membrane absorption of the light is non-resonant, and its transition rate is extraordinarily small, but can be amplified by the coherent state of the identical and independent membrane receptors. The activation coherent states of receptors will activate signal transduction pathway, which was called collective phototransduction. It was shown that collective phototransduction mediated STM was one of the possible mechanisms of photobiomodulation on cell apoptosis.

In this paper, an algorithm for the semiautomatic segmentation of medical image series is proposed by combining the live wire algorithm and the active contour model. Firstly the accurate segmented results of one or more slices in a medical image series are obtained by the livewire algorithm and the watershed transform. Based on the segmentation of previous slices, the computer will segment the nearby slice using the modified active contour model automatically. To make full use of the correlative information between contiguous slices, we introduce a gray-scale model to the boundary points of the active contour model to record the local region characters of the desired object in the segmented slice and scale model. Moreover we introduce the active region concept of the snake to improve the segmentation accuracy. Experiment shows that our algorithm can obtain the boundary of the desired object from a series of medical images quickly and reliably with only little user intervention.

Accurate measurement of tissue optical properties is a key problem in study on optical distribution in tissue. Especially in near infrared range, it is still a hard problem because of affection of strong absorption of water. In this paper, P3 approximation for high absorption was applied theoretically, then device with high precision was designed experimentally for non-scattering transmission measurement and fluence rate measurement. SNR and measuring accuracy were improved by using dual-beam. With added absorber technique at both 632.8nm and 1064nm, optical parameters of 2% intralipid at 1064nm and 1% intralipid at 632.8nm wavelength were obtained. The radial distribution of light through application of Monte Carlo simulation agreed well with the experimental result, which indicated that the experiment system were accurate with root mean square (RMS) less than 8%, and that CuSO₄ as added absorber at 1064nm and NIR was feasible. Optical parameters of turbid media can be measured in NIR.

A method for rapid, non-invasive 2D fluorescence localization of breast cancer using low frequency phased array near-infrared technique is presented in this article. In our study, we have developed a dual-channel fluorescence detection system to locate breast cancer. This system consists two pair of in-phase and out-of-phase light emitting diodes (LEDs) as the light sources and Photomultiplier Tube (PMT) as the detector. Two null planes generated by cancellation of diffusion photon density waves (DPDW) will indicate the 2D position of breast cancer with exogenous contrast agents. The fluorescent contrast agent used in this study is Indocyanine Green (ICG) and the minimum amount of ICG detected by our system is 0.5 μM. With the 2 cm separation of sources and detector, the maximum depth our system can detect is 10 mm. The whole system is in compact size and portable. Phantom experiments show that the system can provide real time detection and localization of small hidden absorbing-fluorescent objects inside the highly scattering medium with high accuracy of ±3 mm. The potential application is that it is low-cost and can be used for breast cancer localization as operation aid and self-examination.

Back Propagation (BP) and Radial Base Function (RBF) neural network methods have been used to design optical fiber temperature sensor probe which is used in medical treatment. Data trained for neural network are gained from experiment and interpolation. New kind of fiber optic temperature sensor with the best sensitivity was designed and made by the method. The selected design scheme is proved to be feasible in the experiment. This method has the characteristics of accuracy, credibility and knowledge-aid design, which are identified by the experiment. This way can save the device cost of design and decrease period of design, which has a good prospect of investigation and application.

We introduce short-time Fourier transform into Fourier transform profilometry(FTP) to extract zero frequency component included in deformed fringe pattern. This method can be used to eliminate zero component by only one deformed fringe pattern instead of two. First we extract zero component of deformed fringe image using short-time Fourier transform and normalize it, then calculate the normalized Fourier spectra of deformed fringe image, finally subtract the zero component from Fourier spectra Fourier spectra of deformed fringe image. We give the theory analysis. Experimental results verify that this method can eliminate zero component and extend the measuring range of Fourier transform profilometry to nearly three times of that of the traditional FTP using a frame deformed fringe image. So it is an efficient method to extend measuring range and keep measuring speed, and the setup is very simple because of no phase shifting device needed.

Optical non-contact 3-D shape measurement provides a novel and useful tool for analysis of facial shape and movement in presurgical and postsurgical regular check. In this article we present a system, which allows a precise 3-D visualization of the patient's facial before and after craniofacial surgery. We discussed, in this paper, the real time 3-D image capture, processing and the 3-D phase unwrapping method to recover complex shape deformation when the movement of the mouth. The result of real-time measurement for facial shape and movement will be helpful for the more ideal effect in plastic surgery.

Photodynamic therapy (PDT) can induce apoptosis in many cancer cells in vitro and in tumors in vivo. Cells become more oxidation with PDT, and maintain differentiation and proliferation, go apoptosis and necrosis with the increase of reactive oxygen species (ROS) concentration. ROS can induce apoptosis through mitochondria by inhibiting respiration chain or oxidative phosphorylation or damaging mitochondrial membrane. ROS can initiate apoptosis through endoplamic reticulum(ER) by opening Ca²⁺ channel or starting unfold protein response (UPR). ROS can also induce apoptosis through Golgi by producing ganglioside GD3 by use of ceramide, which induces apoptosis by activating caspase-3, JNK and p38 MAPK. It can also induce apoptosis by activating Bip (mitochondria-dependant) or preocaspase-12 (mitochondria- independent) or inhibiting protein synthesizing. There are so complicated cross-talking among different signal pathways or organnells that we think PDT-induced apoptosis is mediated by multiplex pathways and excessive levels in a refined network.

A digital x-ray imaging system for small animal studies is introduced. The detector of the system consists of a scintillating screen fiber-optically coupled to two 1024×1024 CCD image arrays. The optical coupling provides about 2 demagnification to math the pixel size at the scintillating screen to the CCD element size. Therefore, the effective pixel size of the detector is 48 μm with the CCD imaging array gives 24 μm pixel spacing. The focal-spot size of the x-ray tube is 20 μm. The x-ray source uses a tungsten target with a 0.25mm-thick beryllium window. The tube current of this system is 0.3mA fixed, and the tube potential from 10 to 35kVp adjustable. The exposure time can be adjusted from 0.1 to 999s. The system can offer the magnification of 1×, 1.5×, 2×, 3×, 4×, and 5×, respectively. The physical characteristics in terms of spatial resolution, noise, and SNR of a CCD based digital x-ray imaging system for small animal studies have been investigated. They are evaluated by measuring modulation transfer function (MTF), noise power spectrum (NPS) and noise equivalent quantum (NEQ). The MTF,NPS and NEQ of three different areas of the CCD detector show high consistency of the three different areas of the CCD detector. The MTF of digital x-ray imaging system different magnifications show the trend of resolution increase as the magnification increasing. NPS and NEQ at different exposure dose are presented as well, which show the trend of noise and the number of Poisson-distributed quanta giving the same signal-to-noise ratio as the exposure dose increasing. Moreover, preliminary tests have been carried out on several samples in order to evaluate the performance of the digital x-ray imaging system. A conclusion can be made that the digital x-ray imaging system can be used to carry out high-resolution analysis in vitro, or in vivo of biomedical samples by proper application.

A thorough analysis of the ultraviolet absorption spectra and light induced fluorescence (LIF) spectral characteristics of ethanol solutions is carried out and discussed in theory and in experiment. The results indicate that ethanol solution can absorb UV-light with the wavelength less than 250nm, and can emit very strong fluorescence when excited by these ultraviolet lights. While the wavelengths of excited lights increase, the fluorescent spectral peaks are apparently red-shifted accordingly. As the ethanol solution concentration increases, the fluorescent spectral peaks are also red-shifted. Furthermore, the physical mechanism of absorption and fluorescence emission of ethanol molecule induced by UV light is analyzed based on the theory of molecule orbital structure. The red-shifted reasons of spectral peaks as the excited light wavelength and the solution concentrations changing are also explained. Investigation on the intrinsic fluorescence spectrum of ethanol solution and its characteristics will contribute to the study of the fluorescence spectra when ethanol serves as solute and hydrolysis catalyst.

Based on the incorporation of the structure and the distance of an amplitude grating, we put forward an equation to calculate the Fresnel diffractive field of the grating with an arbitrary opening ratio at any fractional Talbot distance. Because the transmissive function of a phase grating can be regarded as a linear combination of that of amplitude gratings, from above equation for calculating the Fresnel diffractive field of an amplitude grating, we present an analytical equation to calculate the Fresnel diffractive field of an arbitrary multiple phase grating. Using the analytical equation, we can conveniently study the fractional Talbot effect and its application of the arbitrary multiple phase grating. We give a new approach to analyze the Fresnel diffraction of a grating.

Surface Lambertian source is useful in the course studying the light transmission in biology organization. To simulate the source is necessary start point for researching light transmission characters in tissues. A new method for simulation Lambertian source will be introduced in the paper. Physical model and mathematical model were discussed. The physical model is base, which could be used for simulation other Lambertian objects. The mathematical model should be build in terms of simulated object, which is different from physical model. In order to assure the Lambertian characters of surface light source, the size of source and operation distance were studied by simulation. The simulation data show that this method could give satisfied results.

Fourier transform profilometry (FTP) based on fringe projection has high speed and high procession advantages, so it is widely used in industrial inspection, solid modeling, biomedicine, machine vision and so on. In this paper, we present a novel method, in which we project a bi-color fringe pattern that is consisted of two interlaced RGB base color fringe patterns with π phase difference onto the object using digital light projector and the deformed color pattern is captured by color digital camera. Then the deformed color fringe pattern is decoded into two individual fringe patterns with π phase difference using image-separating technique. After modifying their averages and contrast, we subtract one of the two fringe patterns from the other to eliminate zero spectra. Compared with π phase-shifting technique, the obvious advantage of this method is that only one fringe pattern is needed to remove the zero spectra and raise the measurable slope of height variation nearly three times while no phase shifting device needed. Computer simulation and experiments verify our method.

Three-dimension (3-D) digitization of tooth is becoming an important diagnostic tool of dentistry for the quantitative medicine investigations. In this paper, an optical measurement instrument for tooth data acquisition based on the principle of structured illumination was developed. The instrument consists of a structured illumination optics, a stepping motor driven phase shifting device, a commercial CCD camera system with frame grabber interface and a control personal computer. Because there is no possibility of watching the system directly in the mouth, the measurements were still restricted to plaster casts of the tooth. With a new calibration gauge, both the phase-height mapping and 3D coordinates calibration could be done simultaneously through only one measurement. Additionally, to recover complex shape distribution of the tooth, a phase unwrapping procedure is proposed. The effectiveness of the proposed method is demonstrated by experimental results.

Aim: This experiment studied the light absorption laws of the blood components between 240-800nm. Methods: The absorbance and transmittance of the blood components were measured by applying a model UV-365 double beam scanning spectrophotometer with an integral sphere, between 240-800nm. Results: The results show: 1) The absorbance and transmittance laws resemble each other in blood of the Groups A,B,AB and O. 2) Between 600-800nm, the absorbances of the whole blood, erythrocyte, leukocyte, plasma and serum are less than 5%, while the transmittances of them are more than 95%. 3) To erythrocyte and lymphocyte, typical absorption peaks appear at 416.57±1.90, 542.71±1.80, 578.57±1.81nm. Conclusion: These results provide some useful parameters for the optical properties of blood and the clinical applications.

Intrinsic optical signals imaging (IOSI) and laser speckle imaging (LSI) are both novel techniques for functional neuroimaging in vivo. Combining them to study cortical spreading depression (CSD) which is an important disease model for migraine and other neurological disorders. CSD were induced by pinprick in Sprague-Dawley rats. Intrinsic optical signals (IOS) at 540 nm showed CSD evolution happened in one hemisphere cortex at speeds of 3.7^±0.4 mm/min, and the vasodilation closely correlated a four-phasic response. By LSI, we observed a transient and significant increase cerebral blood flow (CBF). In this paper, optical imaging would be showed as a powerful tool for describing the hemodynamic character during CSD in rat.

Light-emitting diode (LED) technology has provided medicine with a new tool capable of delivering light deep into tissues of the body, at wavelengths which are biologically optimal for cancer treatment, wound healing and other clinical applications. In this paper, a simple review on the clinical use in therapeutic applications as well as in laboratory work of LEDs is given in view of low intensity laser irradiation effects in biomedicine.

In the previous study, we have proved that Pyro-2DG could be trapped and accumulated in the tumor. The fluorescent signal of Pyro-2DG has high correlation with the redox ratio. To further study the extrinsic probe Pyro-2DG, the characteristic of Pyro-2DG uptake by the liver tissue of rats and the distribution of Pyro-2DG in various tissues were detected using the Cryo-Imager. The result indicated that Pyro-2DG uptake by the liver resulted in the metabolic state shift towards an increased concentration of oxidized electron carriers and it completely recovered after 24hrs. Pyro-2DG with infusion injection could avoid the oxidized damage of the normal tissue induced by Pyro-2DG uptake. The distribution of Pyro-2DG in various normal tissues indicated that Pyro-2DG could be as a tumor special near infrared ray (NIR) probe besides the hepatic tumor and lymph system tumor.

In this paper, a new method for image encryption based on chaotic system is proposed. An unpredictable chaotic sequence is generated by Logistic-map, and its characteristics of pseudo-random and sensitiveness to the initial condition helps to construct transformation matrix for image encryption. And two images are used together to encrypt each other in the proposed method for the sake of higher security. An example is used to demonstrate the effectiveness of the proposed method.

We investigated the interaction of a Nd: YAG laser with a sheet metal specimen as a model tissue film in the surrounding of water and air, respectively. By observation of scanning electronic microscopes (SEMs), the morphologies of laser-drilling holes in two mediums are quite different, which closely relates with their different interaction mechanisms. Furthermore, by means of optical beam deflection technique, it is obtained the transient force loading on a metal plate in water and air respectively during pulsed laser radiation. The experimental results are shown that in air the sample is only affected the laser-induced plasma ablation, while in water it is impacted not only ablation, but also two liquid-jet impulses due to bubbles collapse in the vicinity of a boundary. Both the amplitude and duration of three forces underwater are much larger than those in air. In addition, the first liquid-jet impact is obviously larger than laser ablation in water. So the mechanical action, especially the high-pressure liquid-jet impact loading on the sample’s surface in effect outweighs the well-known thermal effect or laser ablation in the pulsed laser medical surgery.

Angiogenesis is an important factor for further tumor growth and thus could be an attractive therapeutic target. Optical imaging can provide a non-invasive way to measure the permeability of tumor blood vessels and assess the tumor vasculature. We have developed a dual-channel near-infrared fluorescence system for simultaneous measurement of the pharmacokinetics of tumorous and normal tissues with exogenous contrast agents. This frequency-domain system consists of the light source (780 nm laser diode), fiber optics, interference filter (830 nm) and the detector (PMT). The fluorescent contrast agent used in this study is Indocyanine Green (ICG), and the normal dosage is 100 μl at a concentration of 5 μM. In vivo animal study is performed on the K1735 melanoma-bearing mouse. The fluorescence signals both tumorous and normal tissues after the bolus injection of ICG through the tail vein are continuously recorded as a function of time. The data is fitted by a double-exponential model to reveal the wash-in and wash-out parameters of different tissues. We observed an elongated wash-out from the tumor compared with normal tissue (leg). The effect of radiation therapy on the tumor vasculature is also discussed.

The lanthanide trivalence ion and its chelates are used for marking substance in time-resolved fluorescence immunoassay(TRFIA), marking the protein, hormone, antibody, nucleic acid probe or biologic alive cell, to measure the concentration of the analysis substance inside the reaction system with time-resolved fluorometry after the reaction system occurred, and attain the quantitative analysis's purpose. TRFIA has been therefore become a kind of new and more sensitive measure method after radioisotope marking, enzymatic marking, chemiluminescence, electrochemiluminescence, it primarily is decided by the special physics and chemistry characteristic of lanthanide trivalence ion and its chelates. In this paper, the result of spectroscopic evaluation of europium trivalence ion and its chelate, and the principle of time-resolved technology and fluorescence-enhanced technology is reported. At the same time, the experiment shows that excitation wavelength chosen between 336 and 337nm benefits the excitation and the energy transfer of chelate diketone of europium trivalence ion.

In this paper, a novel and highly sensitive detection method of singlet oxygen (¹O₂) and superoxide anion (O₂^-) is reported. The principle of the method is similar to that for a measurement of ATP using luciferin and luciferase. A chemiluminescence analytic reagent, 3,7-dihydro-6-{4-[2-(4’-(5-fluoreseinyl)thioureido)ethyl]phenyl}-2-methylimidazo{1,2-a}pyrazin-3-one sodium salt (FCLA), can sensitively react with ¹O₂ and O₂^- and emit photons that can be detected with a single photon counting system. The chemiluminence is significantly enhanced, approximately 20 times, when human serum albumin (HAS) is used in company with the FCLA. In order to further confirm the chemiluminance is due to the reactive oxygen species (ROS), we investigated the relationship between the intensity of the chemiluminence and the concentration of dissolved molecular oxygen, the direct transform source for ¹O₂ and O₂^- in the solution. We found that the intensity of the chemiluminence signal decreased linearly to zero, as nitrogen bursting reduced the concentration of the dissolved oxygen. The results indicate that, the FCLA-HAS combination provides a highly sensitive chemiluminence method for detecting reactive oxygen species, ¹O₂ and O₂^-.

A fiber-optic biosensor is developed based on the principle of evanescent wave while light propagates in optical fiber. The biosensor uses a red laser diode at 636.85 nm for exciting Cy5 fluorescent dye. Sensitivity limit of 0.01 nnmol/l is obtained from the detection of serial Cy5 solutions with various concentrations. In log-to-log plot, excellent linear response characteristic is seen in the Cy5 concentrations ranging from 0.01 nmlo/l to 100 nmol/l. And a good result of signal-to-noise ratio of 4.61 is obtained when the biosensor is used to measure Legionella pneumophila solution of 0.01 μmol/l. All the results are comparable with those that are obtained by a commercial biochip scanner GeneTAC 1000.

An in vitro study was performed to evaluate the laser biostimulatory effect on cartilage using the low-power He-Ne laser. The chondrocytes, isolated from the cartilage of the medial condyle of the femur of the rabbit, were cultivated, incubated and subject to biostimulatory treatment with the laser. The chondrocytes were placed in 96 Petri dishes at the concentration of 0.25×10⁵ cells/ml and divided into 12 groups (3 dishes every group): the first group was used as the control group, other 11 groups (1-11)were treated with the laser. Control cultures received the same treatment with the laser device off. All the groups were evaluated with a MTT test at the end of the laser treatment and then after 5 days. The cultured chondrocytes showed no damage under a fluorescence microscope and immunostaining was operated to confirm the chondrocytic phenotype. The MTT assay results indicated a positive biostimulatory effect of low-power He-Ne laser on cell proliferation. Thereinto, group 5 and 10 provided the best results in terms of cell viability when compared to the other treated groups and the control group. The increase was maintained for 5 days following the end of the laser treatment. The distinct results obtained with the use of the Low-power He-Ne Laser in the biostimulation of the chondrocytes, no damage and no side-effect, permits us to consider the use of the device clinically.

Three-dimensional (3D) information is often required in scientific research. This work describes the set-up of a micro-computed tomography (micro-CT) system based on a digital radiography (DR) system. 3D information of specimen is carried out by the application of tomographic reconstruction algorithms. The DR system has a high spatial resolution, which can provide images of high qualities. The specimen under investigation is arranged on a 3-degrees system (x-y translation and z rotation). The rotation is controlled by a step motor, which can reach up to 0.028 degrees per step. The specimen can be easily moved along the source-detector axis so that different magnifications of details of interest can be obtained. Modulation Transfer function (MTF) of the system has been tested in order to determine its performance. At last, a preliminary experiment has been carried out on biomedical specimen using the micro-CT system.

Autofluorescence spectra from whole blood of laboratory rat are measured in this paper. The excitation lights are light emitting diode (LED), Ar⁺ laser, and He-Ne laser with the wavelength located at 457nm, 457.9nm, and 632.8nm respectively. The three spectral profiles are found to be substantially different, each displaying its own characteristic fluorescence bands. Ar⁺ laser-induced spectrum has very rich and sharp peaks. The LED-induced one has the strongest and widest fluorescence bands. And the intensity of the spectrum induced by He-Ne laser is much lower than the former two. Comparisons of those three fluorescence spectra indicate that Ar⁺ laser induced spectrum can show partly fine structure of blood cells. Based on the theoretical analysis, it is presented that the absorption of the fluorophores in blood cells to the wavelength of exciting light has definite selectivity, which depend on energy level structure and state of the fluorophores.

Optical projection tomography (OPT) microscopy is a new technique to produce high-resolution 3D images of both fluorescent and nonfluorescent biological specimens. It can be used to rapidly map the tissue distribution of RNA and protein expression in intact embryos or organ systems. In optical projection tomography, the specimen is rotated through 360 degrees around a single axis while held in position for imaging. Light passing through specimens is focused onto a digital camera by lenses. After the images of all angles are taken. Sections of specimen are independently reconstructed using the filtered back projection algorithm. This paper presents general guidelines for designing and constructing an OPT microscopy. These guidelines are based on the difficulties encountered during the process of building the system and cover theoretical concepts, optical imaging system and reconstruction algorithm required to build the system. In addition, some suggestions are presented to improve future designs.

Photoacoustic has attracted high attention in recent years, because this imaging technique can combine the advantages of ultrasound and light to improve the image resolution and diagnostic depth of tissues. In this paper, An innovative method of recording photoacoustic (PA) waves in situ is proposed. A focused probe ultrasonic beam passes through a specimen and tags the position of the interested PA signal. The probe-beam interacts nonlinearly with PA wave, which take out more information interaction area. The PA signal in situ is obtained by demodulating the probe-beam. The technique can produce PA signal with high signal-to-noise ratio maging. The filter-back-project algorithm is used for reconstruction. And the PA tomography of a phantom with diameter of 3.5cm is obtained.

Based on the theory of the thermotherapy and recent development, the optical methods are introduced to investigate thermally induced changes in tissue. The typical results show that the scattering coefficient changes with damage integral of tissue, which provides a new method for measurement of damage parameters. By establishing the relationship between the absorption coefficient and dehydration of tissue, it is possible to deduce the dynamics of thermal properties. Optical imaging on thermally induced blood perfusion will help to know the dependence relation of blood and damage integral. It is very important for study dosimetry of thermotherapy based on monitoring of thermotherapy with optical techniques.

Human skin gradually lose its tension and becomes very dry as time flies by. Use of cosmetics is effective to prevent skin aging. Recently, there are many choices of products of cosmetics. To show their effects, It is desirable to develop a way to evaluate quantificationally skin surface condition. In this paper, An automatic skin evaluating method is proposed. The skin surface has the pattern called grid-texture. This pattern is composed of the valleys that spread vertically, horizontally, and obliquely and the hills separated by them. Changes of the grid are closely linked to the skin surface condition. They can serve as a good indicator for the skin condition. By measuring the skin grid using digital image processing technologies, we can evaluate skin surface about its aging, health, and alimentary status. In this method, the skin grid is first detected to form a closed net. Then, some skin parameters such as Roughness, tension, scale and gloss can be calculated from the statistical measurements of the net. Through analyzing these parameters, the condition of the skin can be monitored.

The action curves of free photoelectrons and shallow-trapped electrons in silver halide microcrystals are obtained by microwave absorption phase-sensitivity detection technique. Through comparing the relationship between electronic amounts and exciting intensity, the theory of Gurney-Mott optical absorption is verified. The electronic decay properties in different silver halide microcrystals are analyzed and the effects of electronic behavior on the sensitization properties in silver halide microcrystals are discussed.

The changes of microconfiguration and dynamic changes of monoamines, 5-hydroxytryptamine (5-HT), norepinephrine (NE) and dopamine(DA), in the rat endbrain after exhaustive swimming were observed in order to provide objective reference for evaluation of exercise central fatigue. Thirty-six male SD rates were divided randomly into 4 groups: group control (G₁); group immediate after exhaustive swimming (G₂); group 24 hours after exhaustive swimming (G₃) and group 48 hours after exhaustive swimming (G₄), 9 in each group. After adaptive swimming for 4 days, rats in G₂, G₃ and G₄ took loaded swimming in ratio of 5 g for every 100g body weight (5%) till exhaustion. After decapitation, the endbrains of the rats in each group were taken for ordinary electron microscopic observation of change of microcofiguration and measurement of contents of 5-HT, NE and DA by fluorometric photometer. The ultrastructure of the endbrain cortex in G₂ had apparent changes. In G₃, improvement of ultrastructure of microcirculation in endbrain were observed; In G₄, structure of microcirculation almost recovered to normal level. The level of 5-HT and NE in the endbrain of exhaustive swimming rat increased significantly, up to the highest in G₃ (24h). It was therefore demonstrated that the configuration change of microcirculation and change of 5-HT and NE contents in rat endbrain after exhaustive exercise were synchronous and that the recovery of the configuration change of microcirculation was faster than change of 5-HT and NE contents, the ultrastructure change of microcirculation being reversible. These results indicate that the improvement of microcirculation in endbrain can help promote recovery of sporting central fatigue.

This article describes the work of ALA-PDT to the HL60 cells, which includes parameters of ALA density, Culture time, light dose and optimal wavelength of irradiation, and summarizes the optimize project of experiment using ALA-PD to the HL60 leukaemic cells.

A simple method was found to solve the shortage in the cell size measurement of flow cytometry (FCM). The real-time result can be give out by measure the laser intensity absorbed by the dyed cells. Cooperation with FCM, the distribution of cell size can be got.

The optical biopsy system for nasopharyngeal carcinoma based on the technique of laser-induced exogenous fluorescence has been successful developed. Ar⁺ laser was selected as the excitation light source based on the measurement of the Emission-Excitation Matrix of Hematoporphyrin Monomethyl Ether. Tissue-simulating optical phantoms diluted with different concentration of HMME were used to simulated nasopharyngeal carcinoma lesions in the performance test for the drug-fluorescence optical biopsy system, especially for the comparison of fluorescence image contrast between the excitation wavelength of 488nm and 514.5nm, respectively. Experimental results show that the fluorescence image contrast of simulated nasopharyngeal carcinoma lesions excited by the light at the wavelength of 488nm is about three fold higher than that at 514.5nm, and the sensitivity and resolution of the fluorescence and reflection twilight image can satisfy the needs for clinical diagnosis and localization.

Background: There is little information about the diagnostic value of DNA heterogeneity for breast carcinoma. In this study, DNA content heterogeneity in breast carcinoma, breast benign lesion and breast normal tissue was analyzed to evaluate its diagnostic value for breast carcinomas. Methods: Surgical fresh specimen was minced into cell suspension, which was fixed with 70% ethanol and stained with DAPI. The stained cells were measured by FCM. Results: 1. DNA content analysis showed that all normal tissues and benign lesions are homogeneous. There was only one G0/G1 peak in DNA histogram although 15.32% of benign breast lesion showed slight shift of G0/G1 peak. 78.72% breast carcinomas had aneuploidy stemlines. 70.21% of breast carcinomas were heterogeneous, which included more than two stemlines. DNA content heterogeneity in FNA from 20 cases of breast carcinomas was also detectable. It suggested that DNA content heterogeneity was specific for breast carcinomas. As a diagnostic marker, its specificity, sensitivity and accuracy were 100%, 70.21% and 84.15%, respectively. Conclusion: Measurement of DNA heterogeneity by FCM could provide more diagnostic information for breast carcinomas.

In order to investigating the effect of wavelength on laser blood therapy, we test the fluorescent spectra of human blood. The wavelengths of exciting lights are 530 nm and 632.8 nm respectively. The result indicates that the light of 530 nm induces much stronger fluorescence, and the emitting spectra induced by 632.8 nm is rather different from the spectra induced by the light of 530 nm. This result suggests that the processes of interaction between laser and blood vary with the wavelength of the radiating lights, so the biological effects of the light to blood can differ with wavelength. These facts might have some meanings to the further research for explaining mechanisms of the laser blood therapy.

Optical parameters of tissue have been measured for some biologic tissues ranging from visible wavelengths to near-infrared wavelengths through various measuring techniques up to now. Great differences exist in those measuring results due to difference in experimental methods and theories applied since obtaining of these parameters requires both several experiments and theoretical models for inversion. In this paper we measured optical parameters of tissue phantom through application of measurements of spatially-resolved diffuse-reflectance and transmission rate.

In this paper, spatial distributions of light emitting from slice chicken muscle tissue and sub-skin fatty tissue are measured on experiment. Experimental results indicate that muscle tissue have better diffraction ability, therefore, muscle tissue can't be treated as a kind of highly scattering medium simply and the traditional radiative transfer theory is not suitable for describing its light transporting properties. In order to calculate light transporting in muscle tissues, traditional radiative transfer theory is modified and diffraction effects are considered in the model. The muscle tissue is regarded as a synthesis of scattering, diffraction and absorption. According to the modified theoretical model, numerical calculations are executed for chicken muscle tissues and the results are well matched with experimental measurements. Moreover, based on the modified model, the inversions of the diffractions parameters such as the wavelength of the refractive index fluctuation are also discussed simply.

Biological tissue is a complex medium; only the anisotropy constant g is not enough to describe the scattering property in many situations. Here, the new introducing parameter γ was studied in detail. Our research shown that it is necessary to select appropriate phase function for the applied technology of medical diagnosis and the measurement of optical parameters, because parameter γ more dependents on phase function than parameter g₁, and γ can provide the macrostructure information of tissue as an optical parameter independent of g.

Based on the theory of photon path distribution in semi-infinite homogenous medium, the effect of points with different depth on the detected signal is analyzed, from which a new method of evaluating the spatial reflectance is presented. Furthermore, an approximate theoretical expression of the spatial reflectance in two-layered medium is developed, which agrees with the Monte Carlo simulation results very well.

P₃ approximation of Boltzmann transport equation describes the radiance close to source with accuracy superior to diffuse approximation, which considers the high-order moments of phase function. Here, through studying the influence of two different phase functions on P₃ approximation, we find that the difference of diffuse reflectance in the P₃ approximation is distinct in about 0.45mm close to source for tissue phase function and Henyey-Greenstein (HG) phase function; tissue phase function can more character the microstructure of biological tissue than HG phase function. The research shows light for improving the accuracy of describing the radiance close to source, and of determining the optical properties of small volume tissue.

An optical fiber bioprobe is introduced as a biosensor to monitor the interaction of antigens and antibodies in immunoreactions. The detection is based on the theory of multiple-reflection principles in white-light interferometry. Incident light is partially reflected at the two interface of the biolayer, because of the interference resulted in the interface spectrum. The change of optical thickness can be calculated by testing the reflected spectrum phase shifting. The setup allows the consequent observation of changes in optical pathlength on a fractional nanometer scale with subsecond repetition times. The system has high sensitivity, high precision, cost effective and working on a high reliability. The testing process is nondestructive for the biolayer. The bioprobe is easy integrated as a BIAcore. The system and the experimental results on the reaction of rabbit-IgG with anti-rabbit-IgG are described in this paper.

Optical imaging method was applied into observing the temporal-spatial characteristic of rat primary somatosensory cortex during graded electrical stimulation of the sciatic nerve (5hz,duration of 2s,0.5ms puls,1x,10x and 20x muscle twitch threshold). We found that the temporal and spatial properties of hindlimb somatosensory cortex were modulated by graded intensity electrical stimulation of the sciatic nerve. The magnitude and time course were larger and longer with the intensity raising. And the spatial extent was wider at 20x stimulus than the other two kinds of stimulus. Therefore, our optical imaging was based on 570nm, which only reflect the changes of blood volume. Then our future study will reveal more information of pain modulation in primary somatosensory cortex.

Sports injuries healing has long been an important field in sports medicine. The stimulatory effects of Low intensity laser (LIL) irradiation have been investigated in several medical fields, such as cultured cell response, wound healing, hormonal or neural stimulation, pain relief and others. The aim of this study was to evaluate whether LIL irradiation can accelerate sports injuries healing. Some experimental and clinical studies have shown the laser stimulation effects on soft tissues and cartilage, however, controversy still exists regarding the role of LIL when used as a therapeutic device. Summarizing the data of cell studies and animal experiments and clinic trials by using the biological information model of photobiomodulation, we conclude that LIL irradiation is a valuable treatment for superficial and localized sports injuries and that the injuries healing effects of the therapy depend on the dosage of LIL irradiation.

High-resolution optical mapping based on voltage-sensitive dyes is a relatively new technology that is used to “image” electrical activity in a wide range, from the level of cellular to the whole heart. By using optical recording it is possible to overcome several limitations of other conventional mapping techniques and to depict complex propagation patterns of cardiac transmembrane potentials while it has been proven to be very useful for illuminating basic electrophysiological development. Strategies for maximizing signal-to-noise ratios and removing motion artifacts are the research emphases. Currently, two types of devices dominate in this field, Charge Coupled Devices (CCD) and Photo Diode Arrays (PDA), and some algorithms correcting motion artifacts are used in data processing. In this article, we have attempted to conduct and present a comprehensive review and a perspective of this rapidly developing novel field.

In this paper, a mathematical expression of reflectance point-spread-function, that is defined as the spatial distribution of light diffuse-reflected from biological tissues irradiated by pencil light, is derived from the diffusion approximation (DA) theory. Through calculating partial derivative of the reflectance point-spread function with respect to effective scattering coefficient, we proposed a quantitative criterion for the applicability of diffuse approximation. Moreover, by the introduction of the reflectance point-spread-function, we can use convolution method to calculate the spatial resolved reflectance from dense and thick tissues irradiated by photon beams with finite diameter. We called this method DA based convolution method. Numerical calculations show that the DA based convolution method has much higher computing efficiency compared with the Monte Carlo method.

Low-energy laser have been applied to the therapeutic test in clinics, as the intravascular laser irradiation on blood (ILIB), and it have obtained some therapeutic effects. We researched the action of the low-energy laser to the α-helix protein in theory. The result indicates that the secondary structure of the α-helix protein is possible changed by laser.

In this paper, C-C bond of fibrinogen is considered as a inharmonic oscillator system. It analyses on the interaction of laser on C-C bond of fibrinogen. It point that intra-vascular laser irradiation can reduce the fibrinogen clot in blood and improve blood flow. It is explained by quantum mechanics and simulated by Matlab. It is fit with the clinical effect.

AIM: To investigate the effects of photodynamic therapy on cytokinetics, DNA content and surviving cell fraction of colonic adenocarcinoma cells. METHODS: On the basis of cell culture, after adding verapamil, the effect on the cell cycle, DNA content and surviving cell fraction in photodynamic therapy were studied using fluorescence spectrophotometer, flow cytometer and MTT assay et al. The results were analyzed with SPLM statistical software. RESULTS: After adding PSD(PSD-007,derived from hematoporphy derivative), these intracellular PSD levels of 4.8 and 16 hours exposure increased significantly as compared with that of the adjacent former at the same group respectively, but no significant difference of PSD levels were seen between 16 hours and 24 hours in the same group. The intracellular PSD contents of group PSD and group PSD+Ver had a strong and inverse relationship with surviving cell fractions respectively after photodynamic therapy. The cellular cycle and DNA content were not affected by verapamil alone (0.02 g/ml), but S and G₁ phase cells were decreased, G₂+M phase cells and DNA contents were increased significantly in group PSD+Ver as compared with that of group PSD. CONCLUSION: Verapamil can increase the intracellular photosensitizer content and strengthen the killing power, which affects the cycle and DNA content of colonic adenocarcinoma cells in photodynamic therapy.

In hyperthermia, blood flow plays a major role in determining the effectiveness of hyperthermia used alone or combined with radiation therapy or chemotherapy. The acidity, the nutritional supply, partial pressure of oxygen and distribution of drugs are closely related to blood flow. To facilitate these issues we put forward a simple optical method to measure dynamical change of blood volume combining laser speckle measurement and CCD microscopic imaging technique. In this study, we selected seven different temperatures (40°C, 42°C, 43°C, 44°C, 45°C, 47°C, 49°C), and monitored variations of blood velocity and diameter of microvessels (15~50μm) on BALB/c mouse’s mesentery and through tumor during 30 minutes at each temperature. The results showed that the critical temperatures of normal and tumor microvessel were 43°C and 42°C. Tumor is more thermal sensitive than normal tissue. And the capacity of tumor blood flow to increase upon heating appears to be rather limited. The increase of blood volume was not more than 2.0-fold.

Using the method of quantum of mechanics, the functional mechanism of treatment of ILIB is analyzed. It is believed that the C-C bond in the structure of cholesterol of the red cell will be divided, the rate of cholesterol of red cell / phosphorus fat of film will be reduced, and the fluidity and the capacity of red cell's distortion will be improved, so as to improve the micro-circulation and oxygenic supply for organization. The clinic data of ILIB treatment for 25 cases of brain block support the above opinion.

Three-dimensional (3-D) automatic measurement of an object is widely used in many fields. In Biology and Medicine society, it can be applicable for surgery, orthopedics, viscera disease analysis and diagnosis etc. Here a new fast method to measure the 3D surface of human heart is proposed which can provide doctors a lot of information, such as the size of heart profile, the sizes of the left or right heart ventricle, and the curvature center and radius of heart ventricle, to fully analyze and diagnose pathobiology of human heart. The new fast method is optically and noncontacted and based upon the Phase Measurement Profilometry (PMP), which has higher measuring precision. A human heart specimen experiment has verified our method.

In this paper, a statistical processing method is performed to process the photon images with the small number of photons. The image intensifier is a necessary tool to get a readable image for the ultraweak luminescence, such as the spontaneous light of sample. The photon image is often interfered by the noise caused by the system and the background. And some signal photons were submerged by the noise. For the sake of getting the useful information from the original image, the collected photon images are summed up to increase the number of the samples. According to the distribution regulations of the signal and the noise, a threshold value T is set up to judge if the photon is the signal or not. The noise photons can be reduced and S/N of the photon image is improved. Compared with the pure accumulation of the images and the integrating processing method, the statistical processing method is more effective to process the limited frames of the images with the small number of photons.

The intensity-dependence of photobleaching rate with two-photon excitation (TPE) at biological imaging level has been found to be high-order (>3) relationship. This paper studied experimentally the dependence for rhodamine B (RhB) at two different concentrations under unsaturated absorption conditions. The log-log plot of photobleaching rate versus incident power at concentration of 10^-2M increased with a slope of ~3.7, but that at concentration of 10^-4M increased with a slope of ~2.7.

The technology of micro-electrode arrays is getting more and more important in the research of brain neural networks and its dynamics because of the ability to stimulate and record more neurons’ activities simultaneously. When the signals of many neurons with several noises in a local region are picked up with a microelectrode, a neurophysiologist may wish to sort these signals by assigning particular spikes to putative neurons with some degree of reliability. Spike sorting is a key step in whole data process and is a general problem in neural electrophysiology. Many algorithms for spike sorting have been brought forward based on the features of the spike waveforms from different neurons. In this article, I have accomplished spike sorting through analyzing the amplitude, shape and principal components of the spikes.

Developmental dyslexia is a kind of prevalent psychologic disease. Some functional imaging technologies, such as FMRI and PET, have been used to study the brain activities of dyslexics. NIRS is a kind of novel technology which is more and more widely being used for study of the cognitive psychology. However, there aren’t reports about the dyslexic research using NIRS to be found until now. This paper introduces a NIRS system of four measuring channels. Brain activities of dyslexic subjects and normal subjects during reading task were studied with the NIRS system. Two groups of subjects, the group of dyslexia and the group of normal, were appointed to perform two reading tasks. At the same time, their cortical activities were measured with the NIRS system. This experimental result indicates that the brain activities of the dyslexic group were significantly higher than the control group in BA 48 and that NIRS can be used for the study of human brain activity.

Acetic acid and ethanol solutions can emit fluorescence when induced by 253.7nm UV-light. In this paper, fluorescence spectral characteristics of acetic acid and ethanol solutions are analyzed and studied in theory and in experiment. The results indicate that both acetic acid and ethanol can emit two fluorescence spectral bands, one is from 330nm to 493nm and the other is from 534nm to 665nm. The emitting fluorescence intensity is very sensitive to the solutions concentrations, and fluorescence quenching occurs in some solutions of the two samples. Furthermore, the physical mechanism of fluorescence emission of acetic acid and ethanol molecules is analyzed based on the theory of molecule orbital structure, and the quenching mechanism are studied by the dynamic process. Investigation on the native fluorescence spectrum of the two solvent and their characteristics will contribute to the study of the fluorescence spectra when they serve as solute, hydrolysis catalyst and food additive.

The technique of fluorescence spectroscopy is applied to study thioredoxin reductast (TrxR) in the cells of human brain. Experimental results show that, by the ultraviolet light irradiation (λ_max=253.7nm), TrxR is able to emit two striking spectral bands of 287nm to 484nm and 560nm to 720nm. The spectral profile also consists of some narrow spike-like bands atop these two broad bands. With the concentration of TrxR decreases, the narrow spike-like bands disappear little by little. Furthermore, physical and biochemical mechanisms of fluorescence production for ultraviolet light-induced TrxR spectra and its characteristics are analyzed. The new spectroscopic information suggested in this paper may represent an effort of better understanding of the structure and conformation changes of TrxR.

For studying prefrontal cortical function in short-term memory two tasks were designed. In task one, a plus expression appears on screen for 300 milliseconds every other 2 seconds and the subject is required to give it’s answer but not to remember it. In task two, an Arabic numeral presents on screen as the same frequency as in task one. While a number is present, the subject need adding it to the sum he got last time. As subjects, 26 children participated in the work. Blood volume changes(BVCs) of right prefrontal cortex(PC) under two cognitive tasks were examined using functional near infrared imaging(fNIRI), a noninvasive technique for localizing regional BVCs which correlate with neural activities. The BVCs caused by short-term memory for numbers were retrieved from BVCs by task one and task two. Results revealed that short-term memory is related to PC and the near-infrared spectroscopy(NIRS) can be used to study prefrontal cortical function in short-term memory.

The optical intrinsic signal imaging is an indirect mapping of neuronal activity. The change in light intensity due to neuronal activity are often very small, no more than 0.1-6% of the total intensity of the reflected light in optimal cases, and the noise, which arise from either the biological noise associated with the respiration, circulation and irrelevant physiological activity or the instrumentation noise such as digitization noise, illumination noise, movement artifacts, etc. are usually large. In previous studies, a couple of analysis methods such as Standard Difference, Principal Component Analysis (PCA), Independent Component Analysis (ICA), Truncated Differences were used to suppress these large background noises and extract the small signal of interest from the noisy raw data. The performance of these methods for improving the determination of spatial pattern and time course of the response signal were examined and compared in this paper. The evaluations were employed to both simulated data and experimental optical intrinsic signal imaging data from rat somatosensory cortex during the electrical stimulation at contralateral sciatic nerve.

To research the change characteristics of blood oxygenation content in skeletal muscle, the change regularity between blood oxygenation content and exercise intensity as well as HbO₂ and blood lactate acid while taking incremental exercises, we took an in vivo, real-time and continuous measurement on the blood oxygenation content of eight sportsmen when they did incremental exercises of five degrees on a power bicycle using a portable tissue oximeter which is based on the principle of near-infrared spectroscopy(NIRS), simultaneously, we detected the blood lactate acid of subjects after each degree of incremental physical load instantly using a blood lactate analysis equipment. The results showed that the content of HbO₂ descended regularly while that of Hb ascended; blood volume decreased; and the density of lactate increased as the intensity of exercises was heightened. The statistics analyses showed that the relationship between HbO₂ and blood lactate is rather close (correlation coefficient r=-0.918). With this discovery, a theoretical basis in measuring the relative change of blood oxygenation content non-invasively was evidenced, and a novel technology for assessing the physical situation of sportsman, grasping sports density and evaluating the training effect could be imported.

A novel surface restoral system based on passive stereo vision principle and active raster projection is introduced in this paper. The key techniques of image pre-processing methods in this system are described in detail. Especially, the Local Weighted Image Smoothness (LWIS) and the Selective Image Enhancement (SIE) techniques proposed here are discussed to help the three dimensional data acquisition from the grid stereo images in the surface restoral system. The experiment results prove the efficiency of these image processing methods.

As a ubiquitous intracellular signal, calcium is responsible for controlling numerous cellular processes, such as neuronal signal transmission. In this paper we show that calcium imaging of cultured neuronal network from hippocampus of newborn rats, revealed synchronized calcium wave in intracellular Ca²⁺ concentration and induced calcium oscillation by stimulating embedded-microelectrode on glass substrate.

Near infrared spectroscopy (NIRS) has been developed as a non-invasive method to assess O₂ delivery, O₂ consumption and blood flow, in diverse local muscle groups at rest and during exercise. The aim of this study was to investigate local O₂ consumption in exercising muscle by use of near-infrared spectroscopy (NIRS). Ten elite athletes of different sport items were tested in rest and during step incremental load exercise. Local variations of quadriceps muscles were investigated with our wireless NIRS blood oxygen monitor system. The results show that the changes of blood oxygen relate on the sport items, type of muscle, kinetic capacity et al. These results indicate that NIRS is a potential useful tool to detect local muscle oxygenation and blood flow profiles; therefore it might be easily applied for evaluating the effect of athletes training.

Laser speckle imaging (LSI) through a thinned skull over the somatosensory cortex was utilized to map the spatiotemporal characteristics of local cerebral flood flow (CBF) in anesthetized rats during sciatic nerve stimulation. Region-of-interest selection and Temporal clustering analysis (TCA) method was illustrated on the dataset from high-resolution optical imaging to detect the timing and location of CBF activation. Contralateral hindlimb sensory cortical microflow was activated to increase promptly in less than 1 s after the onset of 2 s electrical stimulation then evolved in different discrete regions. Individual arteries, veins and capillaries in different diameters were activated with the time going. This pattern is similar but slightly elaborated to the results obtained from laser Doppler flowmetry (LDF), functional magnetic resonance imaging (fMRI). We presented this combination to characterize the behaviors of CBF response to neuronal activity, which might possibly lead to a better understanding of neurovascular coupling and fMRI signals.

Learning is crucial for brain functioning, especially for hippocampus. To understand the basis of physiological information processing of hippocampus, we developed the networks of purified-cultured rat hippocampus neurons on a planar 60-microelectrode array MEA. We describe how these networks are prepared, their structure, and the forms of spontaneous activity they exhibit. We stimulate the network at a low frequency until a desired predefined response is observed 50- 10 msec after a stimulus, at which point the stimulus is stopped for 5 min. Repeated cycles of this procedure ultimately lead to the desired response being directly elicited by the stimulus. These results demonstrate that there is learning in networks composed of purified-cultured hippocampus neurons.

A novel Monte Carlo (MC) technique for photon migration through 3D media with the spatially varying optical properties is presented. The employed MC technique combines the statistical weighting variance reduction and real photon paths tracing schemes. The overview of the results of applications of the developed MC technique in optical/near-infrared reflectance spectroscopy, confocal microscopy, fluorescence spectroscopy, OCT, Doppler flowmetry and Diffusing Wave Spectroscopy (DWS) are presented. In frame of the model skin represents as a complex inhomogeneous multi-layered medium, where the spatial distribution of blood and chromophores are variable within the depth. Taking into account variability of cells structure we represent the interfaces of skin layers as a quasi-random periodic wavy surfaces. The rough boundaries between the layers of different refractive indices play a significant role in the distribution of photons within the medium. The absorption properties of skin tissues in visible and NIR spectral region are estimated by taking into account the anatomical structure of skin as determined from histology, including the spatial distribution of blood vessels, water and melanin content. Model takes into account spatial distribution of fluorophores following the collagen fibers packing, whereas in epidermis and stratum corneum the distribution of fluorophores assumed to be homogeneous. Reasonable estimations for skin blood oxygen saturation and haematocrit are also included. The model is validated against analytic solution of the photon diffusion equation for semi-infinite homogeneous highly scattering medium. The results demonstrate that matching of the refractive index of the medium significantly improves the contrast and spatial resolution of the spatial photon sensitivity profile. It is also demonstrated that when model supplied with reasonable physical and structural parameters of biological tissues the results of skin reflectance spectra simulation agrees reasonably well with the results of in vivo skin spectra measurements.