中药类光敏剂金丝桃素的光谱学特性

本研究系统地研究了金丝桃素(HY)的紫外-可见吸收光谱、光漂白和荧光光谱特性,为HY的临床应用提供一定的参考。实验测量了不同浓度HY-二甲基亚砜溶液的紫外-可见吸收光谱,结果显示HY在可见光范围内存在多个吸收峰,其中,594 nm处的吸收最强,这表明594 nm为HY光动力治疗的首选光源波长;HY的光漂白特性研究表明,HY的初始浓度越高,光漂白所需的时间越长;HY的荧光光谱研究表明,荧光光谱在可见光范围内也存在多峰结构,其中,643 nm处的荧光峰最强且半峰宽最窄,因此,在光动力诊断中,采用643 nm荧光发射能大大提高检测的灵敏度。     

650nm低能量激光照射离体高血脂全血和红细胞对其吸收光谱的影响

目的 研究低能量激光照射离体高血脂全血和红细胞对其吸收光谱的影响.方法 选取30例高血脂患者血样为高血脂组,30例正常血样为正常组,用多功能酶标仪分别对血样的全血和红细胞进行扫描,比较两个样本吸收光谱的异同;选用低能量650 nm激光照射待测血样,用多功能酶标仪对全血和红细胞进行扫描并比较照射前后吸收光谱的变化.结果 高血脂血样的全血和红细胞在416、544、578 nm处的吸收峰值均比正常血样高,因此,可通过光谱吸收峰初步判定血液中血脂异常的情况.650 nm激光照射30例高血脂血样后,红细胞在416、544、578 nm处峰值分别降低,照射前后差异具有统计学意义（P＜0.05）;全血照射后其吸收光谱在416、544、578 nm升高,差异具有统计学意义（P＜0.05）.结论 650 nm低能量激光照射可降低高血脂红细胞对光谱的吸收峰,且有助于改善红细胞膜-浆脂质的平衡,从光谱学角度证明了激光治疗高血脂疾病的可行性.     

抗坏血酸快速测定方法

本文采用酚试剂作为氧化剂测定抗坏血酸,显色后即可比色,呈色稳定,具有快速灵敏的优点,初步测定了血浆,组织及食品中抗坏血酸,得到满意结果。回收率为92.1-10.04％。与2.4-二硝基苯肼法比较相关非常显著。 l、吸收光谱:标准抗坏血酸与酚试剂显色后在岛津uv一365型分光光度计上扫描最大吸收峰在750nm处。 2、标准曲线:抗坏血酸标准在     

目测比色法配制高锰酸钾坐浴溶液在直肠肛管疾病患者术后护理中的应用体会

目的 探讨目测比色法配制高锰酸钾坐浴溶液在直肠肛管疾病患者术后中的应用和护理体会.方法 41例直肠肛管手术后患者应用目测比色法配制的0.02％（1∶5000）高锰酸钾溶液坐浴,观察手术创面及肛周皮肤、黏膜损伤情况.结果 41例直肠肛管术后患者使用由目测比色法配制的1∶5000浓度的高锰酸钾溶液坐浴,达到预期疗效,未发生皮肤溃破、黏膜损伤等不良反应.结论 目测比色法配制高锰酸钾坐浴溶液安全有效,操作便捷,易于推广.     

恒磁场对金属离子钻、铬作用下人单核细胞分泌肿瘤坏死因子和细胞凋亡的影响

目的 探讨恒磁场对金属离子钴、铬作用下人外周血单核细胞分泌肿瘤坏死因子的影响,并探讨其对细胞凋亡的动态变化与Caspase-3活性的影响.方法 将CoCl2粉末与CrCl3粉末溶于无菌注射用水配制成CoCl2溶液和CrCl3溶液,从健康人外周血提取单核细胞,将金属离子Co2+Cr3+分别与人单核细胞在不同的磁场强度(10Gs、100Gs、1000Gs)下共培养.实验分8组:Co2+Cr3+组(对照组)、Co2+、Cr3+分别+不同磁场强度(10Gs、100Gs、1000Gs)组,各组细胞于培养12、24、48小时用ELISA法检测上清液中肿瘤坏死因子(TNF-a)的含量:脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测细胞凋亡情况,比色法测定Caspase-3酶活性.结果 经磁场暴露12h之后,各磁场处理组TNF-a量均低于非磁场处理组(P＜0.05),并呈现强度时间依赖性.在100Gs和1000Gs磁场处理组,细胞凋亡率显著高于对照组(P＜0.05),并随着磁场强度的逐渐增大,Caspase-3酶活性逐渐增强.而10Gs磁场组对细胞凋亡及Caspase-3酶活性的改变无明显影响(P＞0.05).结论 一定强度的恒磁场町拮抗金属离子钴、铬刺激人外周血单核细胞分泌TNF-a并且促进其凋亡,为磁场疗法防治假体周围骨溶解提供了理论依据.     

尿酸的表面增强拉曼光谱检验

本文报道了以Ag纳米粒子作为增强基底的尿酸表面增强拉曼光谱(SERS)。文中测试了尿酸、银胶以及尿酸与银胶混合溶液的吸收光谱,探讨尿酸在银胶上可能的增强机制,并对所获得的尿酸溶液的SERS进行初步谱峰归属。同时还讨论了不同吸附时间、不同离子对尿酸增强效应的影响。本文尿酸在银胶中的检测限达到1mg/L。研究结果显示,尿酸溶液的SERS强度随浓度变化,因此,SERS可为尿酸定量检测提供一种直接、快速的新方法。     

扫描治疗头的蒙特卡罗模型研究

目的:评估质子治疗中扫描治疗头对束流品质的影响。方法:通过扫描治疗头的蒙特卡罗模型研究深度剂量曲线的变化,计算射程移位器对束斑截面的影响以及分析扫描磁场对单质子束的偏转情况。结果:随着能量的增加,质子在水中的射程增加,同时散射也越严重,最终布拉格峰变宽,尾端变胖。相比于直接入射水模,通过治疗头后质子在水中的射程缩短了约0.6 cm,但布拉格峰形基本保持不变;将4 cm厚度聚乙烯射程移位器放置于距离水模表面0、10、20、30、40和50 cm分别进行独立计算,发现与水模距离越远,质子的散射越大,因此治疗过程中射程移位器应尽量靠近患者;当扫描磁铁加载磁场后,束斑将偏离束流中心。设置纵向扫描磁场Bx=0.1 T,横向扫描磁场By=0.3 T,180 MeV质子束在Y方向偏离了2.693 cm,横向扫描磁场使质子在-X方向上偏离了8.427 cm。当束流有偏转的时候,要求射程移位器横截面足够大以满足宽扫描场的需要。结论:扫描治疗头的蒙特卡罗模型将有助于理解质子治疗这一新兴的放疗方法以及熟悉扫描治疗的束流特性,在调试和质量保证中提供参考。     

基于TOPAS计算的磁场下质子辐射剂量分析

目的:分析磁场作用下质子束在模体中的剂量分布,为核磁共振引导的质子放疗提供数据参考。方法:采用蒙特卡罗软件TOPAS计算治疗用质子束在核磁共振横向磁场影响下水体模中的剂量分布。同时采用水-空气-水模型研究磁场下的电子回转效应对不同介质交界处质子剂量分布的影响。结果:在均匀水体模中,当磁场强度在0.5 T以内,质子能量在150 MeV以下时,质子布拉格峰位置沿深度方向偏移在1 mm以内,但与束流入射方向平行的XZ面的高剂量区横向侧移在4 mm左右;当磁场强度达到1.5 T时,150 MeV的质子布拉格峰位置偏移在1 mm以内,但横向侧移达10 mm以上。研究结果还发现在磁场作用下,质子在水与空气交界处的剂量无明显变化。结论:利用蒙特卡罗方法可以准确分析磁场下的质子辐射剂量。横向磁场的存在对质子在深度方向的剂量影响较小,但对横向剂量侧移影响较大,且与能量、磁场强度成正比,而电子回转效应对质子在水与空气交界处的剂量影响近似可以忽略。     

鱿鱼软骨Ⅱ型胶原蛋白提取方法及结构分析

目的从鱿鱼软骨中分离纯化非变性II型胶原蛋白,并对其进行结构表征。方法将鱿鱼软骨冻干后粉碎成200目软骨粉,用4%(w/w)Na OH溶液去除多糖、0.5 M EDTA溶液脱灰对软骨进行前处理,采用胃蛋白酶水解提取,Na Cl盐析用纯水透析后冷冻干燥得到II型胶原蛋白样品。通过氨基酸组成分析、SDS-PAGE电泳、紫外吸收光谱、电镜扫描等对制备的样品鉴定。结果制备的II型胶原蛋白具有3条α1链,分子量112 k Da,在224.5 nm波长处有最大紫外吸收,具有三螺旋结构特征。     

静磁场作用下大鼠牙槽骨中前列腺素E_2变化的研究

目的 :通过对大鼠在静磁场和非磁场作用下其牙槽骨的内源性前列腺素 E2 随时间变化的对比研究 ,了解在静磁场作用下 ,大鼠牙槽骨中前列腺素 E2 含量的时间变化性。方法 :放射免疫法检测 2 0只加静磁场、2 0只加非磁场和 4只空白对照的大鼠牙槽骨中前列腺素 E2 的含量 ,探讨静磁场对大鼠牙槽骨的内源性前列腺素 E2 的变化的影响。结果 :未受力时 ,大鼠的牙槽骨内即存在一定数量的前列腺素 E2 。在静磁场作用下 ,牙槽骨的内源性前列腺素 E2 在 1h内即开始升高 ,在 6 h时达高峰 ,随即开始下降 ,但速度缓慢 ,2 4h时仍高于正常。加非磁场组前列腺素 E2 的变化趋势同加磁场组 ,但前列腺素 E2 开始反应慢 ,峰值却高于加磁场组。且12 ,2 4h时的前列腺素 E2 水平亦高于加静磁场组。结论 :牙槽骨的内源性前列腺素 E2 的变化与静磁场的生物学效应有关     

A new elastic tissue stain

A selective elastic tissue stain is described. It is based on a hydrochloric acid alcoholic resorcin fuchsin solution with addition of potassium permanganate and formalin. After preoxidation with potassium permanganate, the mixture diluted with water stains also the beta cells of the islets of Langerhans, the neurosecretory materials, and the HBsAg.     

Study of conformational transitions of graft copolymers by UV spectrophotometry

UV absorption spectra of solutions of vinyl acetate polymers grafted on ethylene oxidepropylene oxide blockcopolymers in (90:10, v/v) ethanol/water mixture are investigated. The spectra of graft copolymers are clearly different from those of blends of the same composition. Conformational transitions of these copolymers occur in dilute solution at 35 and 60°C; the transitions are evidenced by UV differential spectra either compensated with solvent at the same temperature or with solution at 20°C. The absorbance measured at fixed wavelength as a function of temperature shows a change of slope at the transition points. However, the difference between the energies of solution and solvent as measured from differential spectra does not vary monotonously with temperature. It exhibits two minima corresponding to the transition temperatures. The plot of either this energy difference or the ratio of solvent maximum absorbance over solution maximum absorbance (from differential spectra) versus concentration allows to establish a critical concentration. Below this concentration a solution of grafted copolymers may be looked upon as dilute.     

Consistent Silver Methods for Demonstrating Basement Membranes,Reticulum, and Fungi

Abstract

Modifications of the Jones method for basement membranes and reticulum, the Gomori technique for reticulum, and the methods of Grocott and Churukian for fungi are described. The stock methenamine-silver solution used in the Jones method has been reformulated by reducing the amount of silver nitrate and methenamine. Ethylene glycol has been added to help stabilize the solution. The more dilute sodium borate solution is used in this method to simplify preparation of the working methenamine-silver solution. After the kidney sections are oxidized in 0.5% periodic acid, they are treated with 0.5% thiosemicarbazide. Treatment with thiosemicarbazide accelerates the silver reaction with basement membranes. Gomori's technique for reticulum fibers has been modified to eliminate nonspecific background staining, resulting in better visualization of reticulum. Oxidation with acidified potassium permanganate instead of potassium permanganate is essential for elimination of nonspecific background staining. The Grocott procedure for fungi has been revised to shorten the staining time. This has been accomplished by the use of a hot water bath in place of a gravity convection oven. Churukian's method for fungi has been developed to eliminate the use of Gomori's methenamine-silver, which is used in the Grocott method, because it is not stable when heated. This has been accomplished by using dilute ammoniacal silver, which is more stable than methenamine-silver. Staining results achieved by these modified methods are consistent and reliable for demonstrating basement membranes, reticulum, and fungi. (The J Histotechnol 19:211, 1996)     

Rapid spot tests for detecting the presence of adulterants in urine specimens submitted for drug testing

Several adulterants are used to mask tests for abused drugs in urine. Adulterants such as "Klear" and "Whizzies" contain potassium nitrite, and "Urine Luck" contains pyridinium chlorochromate (PCC). The presence of these adulterants cannot be detected by routine specimen integrity checks (pH, specific gravity, and temperature). We developed rapid spot tests for detecting these adulterants in urine. Addition of 3% hydrogen peroxide in urine adulterated with PCC caused rapid formation of a dark brown color. In contrast, unadulterated urine turned colorless when hydrogen peroxide was added. When urine contaminated with nitrite and 2 to 3 drops of 2N hydrochloric acid were added to 2% aqueous potassium permanganate solution, the dark pink permanganate solution turned colorless immediately with effervescence. Urine contaminated with nitrite liberated iodine from potassium iodide solution in the presence of 2N hydrochloric acid. Urine adulterated with PCC also liberated iodine from potassium iodide in acid medium but did not turn potassium permanganate solution colorless. Urine specimens from volunteers and random urine samples that tested negative for drugs did not cause false-positive results. These rapid spot tests are useful for detecting adulterated urine to avoid false-negative drug tests.     

Study on the Interaction Between Tangerine Peel and Beer by Absorption Spectrum

This paper presents a new method to study the interaction between tangerine peel and beer by absorption spectrum.The author explores the change laws and the differences of the absorbance on some wave band from the absorption spectrums of tangerine peel and the mixture of tangerine peel and beer. The results show that there is an obvious difference around 323 nm though the absorbance values of the two samples are almost similar in the most bands. The absorbance value of the mixture is obviously greater than that of tangerine peel at 276 nm in the spectrums, and there is a shift of the peak position in the absorption spectrum of the mixture, which shows the differences of the absorbance values and the peak positions of the two samples. Through comparing the characteristics of the two samples＇ absorption spectrums, a new method for researching new pharmacological action of tangerine peel is presented in this paper. The result indicates that the technology of spectrum analysis will play an important role in the research and development of Chinese herbal pharmacology and new pharmacology.     

A comparison of melanin bleaching and azure blue counterstaining in the immunohistochemical diagnosis of malignant melanoma.

Distinguishing heavily pigmented melanocytes from melanophages on routine hematoxylin and eosin slides can be difficult. Melanin bleaching with potassium permanganate solution is a traditional means of removing melanin from tissues and can be used before immunohistochemical staining to remove any pigment that might be confused with the brown chromogen diaminobenzidine. Azure B stains melanin granules green-blue, easily contrasts with diaminobenzidine, and may be used as a counterstain on unbleached sections after immunohistochemical staining. To our knowledge, studies comparing melanin bleaching with azure B counterstaining in the immunohistochemical evaluation of malignant melanomas have not been performed. Paraffin sections from 33 heavily pigmented malignant melanomas were bleached with a 3.0-g/L potassium permanganate solution, immunohistochemically stained for S-100 and HMB-45, and counterstained with hematoxylin. Unbleached sections were similarly stained for S-100 and HMB-45 and counterstained with azure B. To establish optimal permanganate concentrations, a variable number of sections were bleached with lower permanganate concentrations ranging from 0.125 to 2.5 g/L. S-100 antigenicity was preserved at all permanganate concentrations, whereas HMB-45 antigenicity was abolished at concentrations of 0.5 g/L and greater. At permanganate concentrations from 0.125 to 0.5 g/L, both antigenicities were preserved; however, melanin was incompletely removed. Complications of bleaching included tissue damage and loss of cytologic detail. Positive immunohistochemical staining was observed in azure B counterstained sections. Azure B stained melanin greenblue and was easily distinguished from the brown diaminobenzidine chromogen, regardless of the antibody tested. Neither tissue damage nor loss of cytologic detail was observed. We conclude that the use of azure B counterstaining is superior to permanganate bleaching in the histologic evaluation of heavily pigmented cutaneous malignant melanomas.     

Magnetic-based microfluidic platform for biomolecular separation

A novel microfluidic platform for manipulation of micro/nano magnetic particles was designed, fabricated and tested for applications dealing with biomolecular separation. Recently, magnetic immunomagnetic cell separation has attracted a noticeable attention due to the high selectivity of such separation methods. Strong magnetic field gradients can be developed along the entire wire, and the miniaturized size of these current-carrying conductors strongly enhances the magnetic field gradient and therefore produces large, tunable and localized magnetic forces that can be applied on magnetic particles and confine them in very small spots. Further increases in the values of the generated magnetic field gradients can be achieved by employing miniaturized ferromagnetic structures (pillars) which can be magnetized by an external magnetic field or by micro-coils on the same chip. In this study, we demonstrate magnetic beads trapping, concentration, transportation and sensing in a liquid sample under continuous flow by employing high magnetic field gradients generated by novel multi-functional magnetic micro-devices. Each individual magnetic micro-device consists of the following components: 1. Cu micro-coils array embedded in the silicon substrate with high aspect ratio conductors for efficient magnetic field generation 2. Magnetic pillar(s) made of the magnetic alloy NiCoP for magnetic field focusing and magnetic field gradient enhancement. Each pillar is magnetized by its corresponding coil 3. Integrated sensing coil for magnetic beads detection 4. Microfluidic chamber containing all the previous components. Magnetic fields of about 0.1 T and field gradients of around 300 T/cm have been achieved, which allowed to develop a magnetic force of 3 x 10(-9) N on a magnetic particle with radius of 1 mum. This force is large enough to trap/move this particle as the required force to affect such particles in a liquid sample is on the order of approximately pN. Trapping rates of up to 80% were achieved. Furthermore, different micro-coil designs were realized which allowed various movement modes and with different step-sizes.These results demonstrate that such devices incorporated within a microfluidic system can provide significantly improved spatial resolution and force magnitude for quick, efficient and highly selective magnetic trapping, separation and transportation, and as such they are an excellent solution for miniaturized mu-total analysis systems.     

Characterization of optical parameters with a human forearm at the region from 1.15 to 1.52 microm using diffuse reflectance measurements

Time- and space-resolved diffuse reflectance measurements were used to identify the optical parameters, the reduced scattering and absorption coefficients, of bulk living tissue in the region from 1.15 to 1.52 microm. Although in this region the detector was limited in its temporal resolution, we applied a peak-time shift analysis successfully to determine these coefficients in a human forearm, and then determined the absorption spectrum by space-resolved diffuse reflectance measurements. The absorption spectrum of a water content of 52% determined by magnetic resonance imaging experiments is in good agreement with the absorption coefficient obtained by optical measurements. Moreover, magnetic resonance imaging measurements suggest that the deviation of the absorption coefficients from the water spectrum in the strong water absorption band is caused by the heterogeneity of water distribution in tissue: the low content of water in the skin. These findings indicate that this optical method is potentially applicable to the non-invasive measurement of water in tissue, especially in a region lower than about 1.3-1.35 microm, which may be useful in monitoring oedema and tissue swelling.     

Three-dimensional modeling of a portable medical device for magnetic separation of particles from biological fluids

A portable separator has been developed to quantitatively separate blood-borne magnetic spheres in potentially high-flow regimes for the human detoxification purpose. In the separator design, an array of biocompatible capillary tubing and magnetizable wires is immersed in an external magnetic field that is generated by two permanent magnets. The wires are magnetized and the high magnetic field gradient from the magnetized wires helps to collect blood-borne magnetic nano/micro-spheres from the blood flow. In this study, a 3D numerical model was created and the effect of tubing-wire configurations on the capture efficiency of the system was analyzed using COMSOL Multiphysics 3.3(R). The results showed that the configuration characterized by bi-directionally alternating wires and tubes was the best design with respect to the four starting configurations. Preliminary in vitro experiments verified the numerical predictions. The results helped us to optimize a prototype portable magnetic separator that is suitable for rapid sequestration of magnetic nano/micro-spheres from the human blood stream while accommodating necessary clinical boundary conditions.     

Use of commercially prepared control sera as quality control materials for spectrophotometric bilirubin determinations in amniotic fluid

The visible absorption spectra of dilutions of commercially prepared chemistry control sera closely mimic those of jaundiced amniotic fluids in cases of fetal rhesus isoimmunization. The authors have assessed the use of these materials for the quality control of net absorbance measurements at 450 nm on amniotic fluids. The authors conclude that they are excellent quality control materials because of their ready availability, low cost, long-term stability, wide range of bilirubin concentrations, and their close resemblance to jaundiced amniotic fluids with respect to light absorption and scattering, sensitivity to light, and pigment extractability into chloroform. Their spectra also contain a maximum at 410 nm, so these materials can also be used as controls for net absorbance measurements at 410 nm, a determination that indicates the extent of heme or meconium pigment interference with net absorbance measurements at 450 nm. These materials both supplement and complement the requisite spectrophotometric performance checks of wavelength calibration and photometric accuracy.