光动力疗法发展近况

光动力疗法发展近况李峻亨（解放军总医院激光科北京１００８５３）ＡｂｓｔｒａｃｔＴｈｅｂａｓｉｃｐｒｉｎｃｉｐｌｅｓ，ｐｈｏｔｏｓｅｎｓｉｔｉｚｅｒｓｉｎｃｌｕｄｉｎｇａｐｐｒｏｖｅｄａｎｄｎｅｗｏｎｅｓｉｎｃｌｉｎｉｃａｌｔｒｉａｌｓｔａｇｅｓ．ｌｉ...     

强激光的生物学效应

强激光的生物学效应陈明哲张永珍（北京医科大学第三医院，北京１０００８３）ＡｂｓｔｒａｃｔＥｆｅｃｔｓｏｆｈｉｇｈ－ｌｅｖｅｌｌａｓｅｒｏｎｂｉｏｌｏｇｉｃａｌｔｉｓｓｕｅｉｎｃｌｕｄｅｔｈｅｒｍａｌｅｆｅｃｔ，ｐｒｅｓｓｕｒｅｅｆ－ｆｅｃｔ，ｅｌｅｃ...     

激光辅助的悬雍软腭成形术治疗阻塞性睡眠呼吸暂停症侯群

激光辅助的悬雍软腭成形术治疗阻塞性睡眠呼吸暂停症侯群Ｍｉｃｋｅｌｓｏｎ－ＳＡ．ｅｔａｌ．Ｌａｒｙｎｇｏｓｃｏｐｅ．１９９６；１０６（１ｐｔｌ）１０～１３激光辅助的悬雍垂软腭成形术（ＬＡＵＰ）可减轻因持续性跨咽部组织的严重振额所致的打鼾。操作可在诊察室...     

一种新的乳癌诊断方法——计算机体层激光乳房摄影术

美国佛罗里达州迈阿密的成像诊断系统公司（ＩｍａｇｉｎｇＤｉａｇｎｏｓｔｉｃｓＳｙｓｔｅｍｓ,Ｉｎｃ．）开发了一种新的激光成像技术——计算机体层激光乳房摄影术（ＣｏｍｐｕｔｅｄＴｏｍｏｇｒａｐｈｙＬａｓｅｒＭａｍｍｏｇｒａｐｈｙ,ＣＴＬＭ）。它可以提供高分辨的乳房摄影,而没有常规乳房成像诊断中的辐射和挤压乳房时的疼痛现象,也不象Ｘ线乳房摄影那样呈单视图影像,而是可以构成乳房组织三维视图的连续的横断层影像。美国食品药品管理局已批准该公司试验研究ＣＴＬＭ检查方案和诊断标准。据公司开发这一技术的理查德·…     

紫翠宝石激光（755nm 100nsec）去除纹身色素在动物模型中的应用

可能除了Ｑ开关红宝石激光和Ｑ开关Ｎｄ：ＹＡＧ激光外，以前所有去除纹身的治疗方法都会导致疤痕的形成。目的 这项研究的目的是考察一种新的激光，应用这种激光可去除纹身而不留疤痕。方法 专业纹身艺术家以黑色、蓝色、绿色和红色染料对一只Ｙｕｃａｔａｎ小型猪进行纹身。然后用单发的紫翠宝石激光（波长７５５ｎｍ，脉宽１００ｎｓｅｃ）治疗这些纹身，并进行临床及组织学评估。以氩离子激光（波长４８８ｎｍ，５１４ｎｍ，连续波长）进行比较治疗，同样，以闪光灯泵浦染料激光（波长５８５ｎｍ，脉宽４５０μｓｅｃ）去除红色纹身进行比较。结果 紫翠宝石激光对去除专业或业余的黑色纹身素非常有效，对去除蓝色和绿色色素中等有效，对去除红色色素的效果最小。结论 紫翠宝石激光作为一种无疤痕去除纹身的方法很有应用前景。     

Studies on heart development in normal and cardiac mutant axolotls,Ambystoma Mexicanum,using cellular and molecular biology

ＴｈｅＭｅｘｉｃａｎａｘｏｌｏｔｌ(Ａｍｂｙｓｔｏｍａｍｅｘｉｃａｎｕｍ)ｐｒｏｖｉｄｅｓａｎｄｅｘｃｅｌｌｅｎｔｍｏｄｅｌｆｏｒｓｔｕｄｙｉｎｇｈｅａｒｔｄｅｖｅｌｏｐｍｅｎｔｓｉｎｃｅｉｔｃａｒｒｉｅｓａｓｉｍｐｌｅｒｅｃｅｓｓｉｖｅｃａｒｄｉａｃｌｅｔｈａｌｍｕｔａｔｉｏｎｔｈａｔｒｅｓｕｌｔｓｉｎａｆａｉｌｕｒｅｏｆｍｕｔａｎｔｅｍｂｒｙｏｎｉｃｍｙｏｃａｒｄｉｕｍｔｏｃｏｎ ｔｒａｃｔ.Ｉｎｃａｒｄｉａｃｍｕｔａｎｔａｘｏｌｏｔｌｓｔｈｅｈｅａｒｔｓｄｏｎｏｔｂｅａｔ,ａｐｐａｒｅｎｔｌｙ…     

浅析激光细胞工程的应用

浅析激光细胞工程的应用周胜军白智鹏刘凤军解放军北京医学高等专科学校医学工程系（北京１０００７１）周胜军：男，２６岁，重庆大学光电精密仪器研究所硕士研究生毕业，解放军北京医学高等专科学校教员，助教。引言激光细胞工程（ｌａｓｅｒｃｅｌｅｎｇｉｎｅｅｒｉｇ...     

The study on the levels of sIL-2R and TNF-αin the aqueous of Rhesus M onkeyseyesim planted w ith F-heparin surface m odified IOLs

Ｐｏｌｙｍｅｔｈｙｌｍｅｔｈａｃｒｙｌａｔｅ（ＰＭＭＡ）ｉｎｔｒａｏｃｕｌａｒｌｅｎｓ（ＩＯＬｓ）ｕｓｅｄｃｏｍｍｏｎｌｙｌｅｄｔｏｓｏｍｅｃｏｍｐｌｉｃａｔｉｏｎｓｉｎｃｌｕｄｉｎｇｉｎｆｌａｍｍａｔｏｒｙｒｅｓｐｏｎｓｅ，ｆｏｒｅｉｇｎｂｏｄｙｒｅａｃｔｉｏｎ，ｃｅｌｌｕｌａｒａｎｄｐｉｇｍｅｎｔａｌｄｅｐｏｓｉｔｉｏｎｏｎｔｈｅＩＯＬｓｕｒｆａｃｅａｎｄｐｏｓｔｅｒｉｏｒｃａｐｓｕｌｅｏｐａｃｉｆｉｃａｔｉｏｎ．Ｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｆａｃｔｏｒｃａｕｓｉｎｇｔｈｅｓｅｃｏｍｐ…     

Interleukin - 3 and granulocyte -macrophage colony -stimulating factor levels of cord blood plasma in term neonates

ＡＩＭ :Ｕｍｂｉｌｉｃａｌｃｏｒｄｂｌｏｏｄｐｌａｓｍａｃｏｎｔａｉｎｈｉｇｈｅｒｈｅｍａｔｏｐｏｉｅｔｉｃｓｔｉｍｕｌａｔｏｒｙａｃｔｉｖｉｔｉｅｓｔｈａｎａｄｕｌｔｐｅｒｉｐｈｅｒａｌｂｌｏｏｄｐｌａｓｍａ .ＩＬ - 3ｉｓｒｅｇａｒｄｅｄａｓｍｕｌｔｉｌｉｎｅａｇｅｈｅｍａｔｏｐｏｉｅｔｉｃｇｒｏｗｔｈｆａｃｔｏｒｔｈａｔａｃｔｓｏｎｐｒｉｍｉｔｉｖｅｐｌｕｒｉｐｏｔｅｎｔｉａｌｓｔｅｍｃｅｌｌｓａｎｄｐｒｏｇｅｎｉｔｏｒｃｅｌｌｓｏｆｅｖｅｒｙｌｉｎｅａｇｅｅｘｃｅｐｔＴａｎｄＢ -ｌｙｍｐｈ…     

Study on preparation and properties ofbiofunctionally gradient coatingsw ith m agnetron cosputtering

ＩＮＴＲＯＤＵＣＴＩＯＮ　　Ｔｈｅｄｉｆｆｅｒｅｎｃｅｓｏｆｓｔｒｕｃｔｕｒｅａｎｄｐｈｙｓｉｃａｌｐｒｏｐｅｒｔｉｅｓｂｅｔｗｅｅｎｔｈｅｃｏａｔｉｎｇａｎｄｔｈｅｓｕｂｓｔｒａｔｅｍａｋｅｔｈｅｂｏｕｎｄａｒｙｚｏｎｅｂｅｃｏｍｅｔｈｅｗｅａｋｅｓｔｚｏｎｅｏｆｔｈｅｗｈｏｌｅｃｏｍｐｏｓｉｔｅｓｙｓｔｅｍ，ｓｔｕｄｙｏｎｉｍｐｒｏｖｉｎｇｔｈｅａｄｈｅｓｉｏｎｏｆｃｏａｔｉｎｇｔｏｓｕｂｓｔｒａｔｅｉｓａｌｗａｙｓａｎａｔｔｒａｃｔｉｖｅａｎｄａｃｔｉｖｅｆｉｅｌｄ〔１～４〕．Ａｎｄｔｈ…     

Calculation of absorbed dose and biological effectiveness from photonuclear reactions in a bremsstrahlung beam of end point 50 MeV.

The absorbed dose due to photonuclear reactions in soft tissue, lung, breast, adipose tissue and cortical bone has been evaluated for a scanned bremsstrahlung beam of end point 50 MeV from a racetrack accelerator. The Monte Carlo code MCNP4B was used to determine the photon source spectrum from the bremsstrahlung target and to simulate the transport of photons through the treatment head and the patient. Photonuclear particle production in tissue was calculated numerically using the energy distributions of photons derived from the Monte Carlo simulations. The transport of photoneutrons in the patient and the photoneutron absorbed dose to tissue were determined using MCNP4B; the absorbed dose due to charged photonuclear particles was calculated numerically assuming total energy absorption in tissue voxels of 1 cm3. The photonuclear absorbed dose to soft tissue, lung, breast and adipose tissue is about (0.11-0.12)+/-0.05% of the maximum photon dose at a depth of 5.5 cm. The absorbed dose to cortical bone is about 45% larger than that to soft tissue. If the contributions from all photoparticles (n, p, 3He and 4He particles and recoils of the residual nuclei) produced in the soft tissue and the accelerator, and from positron radiation and gammas due to induced radioactivity and excited states of the nuclei, are taken into account the total photonuclear absorbed dose delivered to soft tissue is about 0.15+/-0.08% of the maximum photon dose. It has been estimated that the RBE of the photon beam of 50 MV acceleration potential is approximately 2% higher than that of conventional 60Co radiation.     

Influence of uterine cervix shape on photodynamic therapy efficiency

The goal of practical photodynamic therapy (PDT) dosimetry is to optimize the distribution of a light dose delivered to tissue by selecting the irradiation time and geometry to match the geometry and optical properties of the tumor and surrounding tissue. Homogeneous irradiation is among one of the sources of correct PDT dosimetry. The goal of this study is to model and predict the influence of the shape of a treated organ in need of light dose correction. Thus efficiency of light delivery to the tissue volume is defined and calculated with shape factors of the uterine cervix as parameters. Two cases (parallel and divergent beam) of enlightening configuration are investigated. The calculations presented extend PDT dosimetry with the influence of the shape of the uterine cervix on PDT necrosis depth. This allows for photodynamic excitation light dose correction for more reliable treatments.     

Converting absorbed dose to medium to absorbed dose to water for Monte Carlo based photon beam dose calculations

Current clinical experience in radiation therapy is based upon dose computations that report the absorbed dose to water, even though the patient is not made of water but of many different types of tissue. While Monte Carlo dose calculation algorithms have the potential for higher dose accuracy, they usually transport particles in and compute the absorbed dose to the patient media such as soft tissue, lung or bone. Therefore, for dose calculation algorithm comparisons, or to report dose to water or tissue contained within a bone matrix for example, a method to convert dose to the medium to dose to water is required. This conversion has been developed here by applying Bragg-Gray cavity theory. The dose ratio for 6 and 18 MV photon beams was determined by computing the average stopping power ratio for the primary electron spectrum in the transport media. For soft tissue, the difference between dose to medium and dose to water is approximately 1.0%, while for cortical bone the dose difference exceeds 10%. The variation in the dose ratio as a function of depth and position in the field indicates that for photon beams a single correction factor can be used for each particular material throughout the field for a given photon beam energy. The only exception to this would be for the clinically non-relevant dose to air. Pre-computed energy spectra for 60Co to 24 MV are used to compute the dose ratios for these photon beams and to determine an effective energy for evaluation of the dose ratio.     

Determination of the tumor tissue optical properties during and after photodynamic therapy using inverse Monte Carlo method and double integrating sphere between 350 and 1000 nm

Photodynamic therapy (PDT) efficacy depends on the amount of light distribution within the tissue. However, conventional PDT does not consider the laser irradiation dose during PDT. The optical properties of biological tissues (absorption coefficient μ(a), reduced scattering coefficient μ's), anisotropy factor g, refractive index, etc.) help us to recognize light propagation through the tissue. The goal of this paper is to acquire the knowledge of the light propagation within tissue during and after PDT with the optical property of PDT-performed mouse tumor tissue. The optical properties of mouse tumor tissues were evaluated using a double integrating sphere setup and the algorithm based on the inverse Monte Carlo method in the wavelength range from 350 to 1000 nm. During PDT, the μ(a) and μ's were not changed after 1 and 5 min of irradiation. After PDT, the μ's in the wavelength range from 600 to 1000 nm increased with the passage of time. For seven days after PDT, the μ's increased by 1.7 to 2.0 times, which results in the optical penetration depth decreased by 1.4 to 1.8 times. To ensure an effective procedure, the adjustment of laser parameters for the decreasing penetration depth is recommended for the re-irradiation of PDT.     

Absorbed dose in the presence of contrast agents during pediatric cardiac catheterization

Administration of x-ray contrast agents during heart catheterization examination increases the absorbed radiation dose in tissue. To estimate the dose absorbed by the blood of children undergoing diagnostic heart catheterization and angiocardiography, a number of measurements and calculations were conducted. First, entrance and exit exposures to the patient were measured with thermoluminescent dosimeters calibrated for the diagnostic x-ray energy range. Second, a dose enhancement factor was calculated from mass energy absorption coefficients for various concentrations of the contrast media and at selected x-ray energies. Third, the dose enhancement factor was estimated from survival of peripheral blood lymphocytes suspended in varying concentrations of the contrast agent during exposure to graded doses of x-rays. Fourth, a mean absorbed dose to the patient's blood was calculated using (a) the dose enhancement factor determined above, (b) an estimate of the mean exposure in the irradiated body volume calculated from the entrance and exit exposure measurements, (c) an effective iodine concentration in the blood during the exposure time, and (d) a ratio correcting for the distribution and circulation of the blood. For eight pediatric patients monitored, absorbed doses to the blood ranged between 3 and 12 rad. These values were two to three times greater than the expected dose without administration of a contrast agent.     

Correlation of in vivo photosensitizer fluorescence and photodynamic-therapy-induced depth of necrosis in a murine tumor model

We compared light-induced fluorescence (LIF) to nominal injected drug dose for predicting the depth of necrosis response to photodynamic therapy (PDT) in a murine tumor model. Mice were implanted with radiation-induced fibrosarcoma (RIF) and were injected with 0, 5, or 10 mg/kg Photofrin. 630-nm light (30 J/cm(2), 75 mW/cm(2)) was delivered to the tumor after 24 hours. Fluorescence emission (lambda(excitation)=545 nm, lambda( emission)=628 nm) from the tumor was measured. The LIF data had less scatter than injected drug dose, and was found to be at least as good as an injected drug dose for predicting the depth of necrosis after PDT. Our observations provide further evidence that fluorescence spectroscopy can be used to quantify tissue photosensitizer uptake and to predict PDT tissue damage.     

Updated results of a phase I trial of motexafin lutetium-mediated interstitial photodynamic therapy in patients with locally recurrent prostate cancer.

Locally recurrent prostate cancer after treatment with radiation therapy is a clinical problem with few acceptable treatments. One potential treatment, photodynamic therapy (PDT), is a modality that uses laser light, drug photosensitizer, and oxygen to kill tumor cells through direct cellular cytotoxicity and/or through destruction of tumor vasculature. A Phase I trial of interstitial PDT with the photosensitizer Motexafin lutetium was initiated in men with locally recurrent prostate cancer. In this ongoing trial, the primary objective is to determine the maximally tolerated dose of Motexafin lutetium-mediated PDT. Other objectives include evaluation of Motexafin lutetium uptake from prostate tissue using a spectrofluorometric assay and evaluation of optical properties in the human prostate. Fifteen men with biopsy-proven locally recurrent prostate cancer and no evidence of distant metastatic disease have been enrolled and 14 have been treated. Treatment plans were developed using transrectal ultrasound images. The PDT dose was escalated by increasing the Motexafin lutetium dose, increasing the 732 ran light dose, and decreasing the drug-light interval. Motexafin lutetium doses ranged from 0.5 to 2 mg/kg administered IV 24, 6, or 3 hr prior to 732 ran light delivery. The light dose, measured in real time with in situ spherical detectors was 25-100 J/cm2. Light was delivered via optical fibers inserted through a transperineal brachytherapy template in the operating room. Optical property measurements were made before and after light therapy. Prostate biopsies were obtained before and after light delivery for spectrofluorometric measurements of photosensitizer uptake. Fourteen patients have completed protocol treatment on eight dose levels without dose-limiting toxicity. Grade I genitourinary symptoms that are PDT related have been observed. One patient had Grade II urinary urgency that was urinary catheter related. No rectal or other gastrointestinal PDT-related tox-icities have been observed to date. Measurements of Motexafin lutetium demonstrated the presence of photosensitizer in prostate tissue from all patients. Optical property measurements demonstrated substantial heterogeneity in the optical properties of the human prostate gland which supports the use of individualized treatment planning for prostate PDT.     

研究不同光敏剂诱导的光动力疗法对人白血病细胞的杀伤作用

目的 研究并比较3种卟啉类光敏剂——血卟啉衍生物(HpD)、癌光啉(PsD007)和血卟啉 单甲醚(HMME)诱导的光动力疗法(PDT)对白血病细胞K562的杀伤效应.方法 以人白血病细胞K562为研究对象,分为对照组和PDT组,以梯度浓度的光敏剂与K562细胞共同孵育,经不同能量光照后,用噻唑蓝(MTT)法测定PDT对K562细胞的杀伤作用.结果 与对照组相比,PDT对K562细胞有明显杀伤作用,并随着光敏剂浓度的增加和光照能量的增大,效果增强.PsD007-PDT和HMME-PDT的效果都明显优于HpD-PDT(P＜0.05);而当光敏剂质量浓度较大(25 μg/ml)或能量密度较大(7.2 J/cm2)时,PsD007-PDT的作用效果优于HMME-PDT.结论 PDT对人白血病细胞K562具有明显的杀伤作用,其对细胞的抑制率具有显著的剂量效应关系;PDT对K562的杀伤效应与光敏剂种类有关,HpD-PDT的杀伤效果不如PsD007和HMME;在较高能量密度和较大光敏剂浓度的条件下,PsD007-PDT的效果优于HMME-PDT.     

Realtime light dosimetry software tools for interstitial photodynamic therapy of the human prostate

Photodynamic therapy (PDT) for the treatment of prostate cancer has been demonstrated to be a safe treatment option capable of inducing tissue destruction and decreasing prostate specific antigen (PSA) levels. However, prostate-PDT results in large intra- and interpatient variations in treatment response, possibly due to biological variations in tissue composition and short-term response to the therapeutic irradiation. Within our group, an instrument for interstitial PDT on prostate tissue has been developed that combines therapeutic light delivery and monitoring of light transmission via numerous bare-ended optical fibers. Here, we present algorithms that utilize data on the light distribution within the target tissue to provide realtime treatment feedback based on a light dose threshold model for PDT. This realtime dosimetry module is implemented to individualize the light dose and compensate for any treatment-induced variations in light attenuation. More specifically, based on the light transmission signals between treatment fibers, spatially resolved spectroscopy is utilized to assess the effective attenuation coefficient of the tissue. These data constitute input to a block-Cimmino optimization algorithm, employed to calculate individual fiber irradiation times provided the requirement to deliver a predetermined light dose to the target tissue while sparing surrounding sensitive organs. By repeatedly monitoring the light transmission signals during the entire treatment session, optical properties and individual fiber irradiation times are updated in realtime. The functionality of the algorithms is tested on diffuse light distribution data simulated by means of the finite element method (FEM). The feasibility of utilizing spatially resolved spectroscopy within heterogeneous media such as the prostate gland is discussed. Furthermore, we demonstrate the ability of the block-Cimmino algorithm to discriminate between target tissue and organs at risk (OAR). Finally, the realtime dosimetry module is evaluated for treatment scenarios displaying spatially and temporally varying light attenuation levels within the target tissue. We conclude that the realtime dosimetry module makes it possible to deliver a certain light dose to the target tissue despite spatial and temporal variations of the target tissue optical properties at the therapeutic wavelength.     

Electron absorbed fractions of energy and S-values in an adult human skeleton based on µCT images of trabecular bone

When the human body is exposed to ionizing radiation, among the soft tissues at risk are the active marrow (AM) and the bone endosteum (BE) located in tiny, irregular cavities of trabecular bone. Determination of absorbed fractions (AFs) of energy or absorbed dose in the AM and the BE represent one of the major challenges of dosimetry. Recently, at the Department of Nuclear Energy at the Federal University of Pernambuco, a skeletal dosimetry method based on μCT images of trabecular bone introduced into the spongiosa voxels of human phantoms has been developed and applied mainly to external exposure to photons. This study uses the same method to calculate AFs of energy and S-values (absorbed dose per unit activity) for electron-emitting radionuclides known to concentrate in skeletal tissues. The modelling of the skeletal tissue regions follows ICRP110, which defines the BE as a 50 μm thick sub-region of marrow next to the bone surfaces. The paper presents mono-energetic AFs for the AM and the BE for eight different skeletal regions for electron source energies between 1 keV and 10 MeV. The S-values are given for the beta emitters (14)C, (59)Fe, (131)I, (89)Sr, (32)P and (90)Y. Comparisons with results from other investigations showed good agreement provided that differences between methodologies and trabecular bone volume fractions were properly taken into account. Additionally, a comparison was made between specific AFs of energy in the BE calculated for the actual 50 μm endosteum and the previously recommended 10 μm endosteum. The increase in endosteum thickness leads to a decrease of the endosteum absorbed dose by up to 3.7 fold when bone is the source region, while absorbed dose increases by ～20% when the beta emitters are in marrow.