Column-like structures following the course of tubules in human dentin

Abstract – Sections, 60–180μm thick, of permanent teeth, intact or with minor fillings, were cut parallel or transversal to the course of the dentinal tubules. Some teeth were dermineralized, embedded in paraffin wax, cut in series, and stained with toluidine blue pH 5.6, hematoxylineosin, or PAS. Altogether, sections of 90 teeth were examined by ordinary and polarized light microscopy and contact microradiography. Alternating light and dark bands, usually 8–30μm wide, extended from the pulpal border along the course of the tubules, gradually increasing in width, fading in the mantle dentin. Cross-sectioned bands appeared as dark and light "discs". This was the background for the term "columns". In the dark columns, usually exhibiting crowding of tubules, the intertubular dentin was dark and radiolucent; in the light columns, light and radiopaque. Dark columns contained a high amount of GAGs, assumed to have exerted an inhibitory effect on their mineralization. The columns probably represent structural elements in the architecture of dentin, possibly offering resistance against mechanical stress. It was suggested that the columns might depict functional differences in the matrix secretion and mineralization capacities of odontoblasts.     

天狼猩红饱和苦味酸染色在大鼠胰腺纤维化评价中的应用

目的 应用苦味酸天狼猩红-偏振光法评价长期高脂饮食导致的胰腺纤维化。 方法 建立18周高脂饮食大鼠模型，HE染色观察胰腺形态变化，苦味酸天狼猩红-偏振光法对胰腺纤维化特点进行评价。 结果 长期高脂饮食可以导致大鼠胰腺纤维化改变，对苦味酸天狼猩红染色结果进行图像分析显示胶原纤维含量较正常组明显增加 (p<0.01)，偏光镜下观察示以I、III胶原为主要成分。结论 苦味酸天狼猩红-偏振光法是评价胰腺纤维化胶原沉积的有效方法。     

Quantitative assessment of myocardial collagen with picrosirius red staining and circularly polarized light

Summary Collagen plays a major role in the structural organization of the heart and therefore direct visualization of collagen fibers is a crucial component of cardiac analysis. Although linearly polarized light has proven an effective tool for the examination of myocardial collagen in histologic sections, the use of circularly polarized light may offer advantages and additional possibilities. We examined the potential enhancement of collagen analysis using circularly polarized light in two ways. We first measured the brightness, and hence indirectly assessed the birefringence, of collagen fibers in scars examined at different times after myocardial infarction. Secondly, we measured collagen content in myocardial tissue and compared results obtained from brightfield analysis of trichrome stained sections with those obtained from circularly polarized light analysis of picrosirius red stained sections. We observed a progressive increase in the maximum brightness of collagen fibers in the scar with time, and a time-dependent shift in the relative distribution of collagen fiber brightness from lower to higher levels. We found consistently lower values of collagen content in trichrome stained versus picrosirius red stained tissue, and concluded that trichrome staining underestimated collagen content. The information provided by these studies could not be obtained by brightfield analysis and could be only partially obtained from linearly polarized light analysis. Thus, analysis using circularly polarized light has the ability to enhance histologic assessment of tissue and can provide additional insights into the composition and structure of myocardial collagen.Presented in part at the 64th Scientific Sessions of the American Heart Association in Anaheim, California, November 1991     

发育性髋关节脱位关节囊(胶原)组织偏光显微镜观察及临床病理意义

目的 观察发育性髋关节脱位(developmental dislocation of the hip,DDH)与正常儿童的髋关节囊的形态学特点,分析Ⅰ型和Ⅲ型胶原含量及二者比例(Ⅰ/Ⅲ)变化规律.方法 2005年6月～2006年8月第一次手术DDH患儿42例,男8例,女34例,排除胶原代谢疾病及其他畸形.对照组选择因其他疾病第一次行髋关节手术及尸检患儿共20例,男7例,女13例,1.5～14岁,平均7.4岁,无DDH病史,排除胶原代谢疾病及其他畸形.根据术前X线片,按Tonnis分类将DDH患儿分为四组,分别与正常对照组对比分析.关节囊取材于手术或尸检切除标本,行苦味酸-天狼猩红染色,分别在普通显微镜和偏振光显微镜下观察并测量Ⅰ型和Ⅲ型胶原含量及计算比例(Ⅰ/Ⅲ).结果 对照组与Tonnis各组分别进行t检验,差异有统计学意义(P=0.000<0.01);病例组间进行方差分析,差异无统计学意义(0.1250.05);但是其值病例组要明显低于对照组(P<0.05).结论 DDH患儿和对照组间关节囊Ⅰ和Ⅲ型胶原含量及比例(Ⅰ/Ⅲ)有较大差别,但是脱位高患儿并不一定会有明显形态学上改变.     

测定极化聚合物膜的二阶非线性光学系数的新方法──偏振红外光谱法

本文报道在一维刚性取向气体模型基础上用偏振红外光谱测出的极化膜的取向度估算其二阶非线性光学系数α值的方法。方法表明,在目前采用的各种极化方法所能达到的极化效率范围内,取向因子可表示为     

Characterizing the Three‐Dimensional Orientation in Polymers using FT‐IR Spectroscopy with Linear Polarized Light

The quantity of absorbance of linear polarized light depends for a given wavelength on the angle between an absorbing transition moment vector and the electric vector of the polarized light. Fraser used this relationship to interpret the infrared dichroism in axially oriented polymers. This model can be extended to calculate the orientation in three dimensions by transforming the Fraser's equation into a P₂‐Legendre polynomial. As a result the orientation in three directions—f_x, f_y, and f_z—can be calculated directly from the individual absorbances measured with an electric vector along the axes of interest, the structural absorbance A₀ of the sample, and the angle of the transition moment vector in reference to the chain axis. Applying the f values into ‘Hermans’ Orientation function', it becomes possible to calculate the average angle of the chain axis with reference to the axes of interest.

     

离子自组装超分子荧光材料及其光致各向异性特性

采用离子自组装的方法,制备了侧链含有肉桂酸光敏基元和二苯乙烯荧光基元的新型超分子复合物PCAMSTIL。通过核磁共振（NMR）和红外光谱（FT-IR）表征了该超分子复合物的结构,并用热重分析(TGA)、紫外可见光谱（UV-Vis）和荧光光谱(FL)研究了其热稳定性和光学性能。将PCAMSTIL旋涂成膜,薄膜经过266 nm偏振脉冲激光辐照后,肉桂酸发生轴向选择的［2+2］加成,薄膜垂直于激光偏振方向的紫外可见吸收明显大于平行方向的吸收,证实薄膜具有取向性。取向薄膜的最大吸收二向色性取向值最大可达0.103,优于一般肉桂酸材料的取向性,肉桂酸分子的取向也引起二苯乙烯荧光分子的协同取向,荧光偏振发射比可达1.73。     

高压氧联合直线偏振光近红外线照射对难治性溃疡的疗效

目的探讨高压氧联合直线偏振光近红外线照射对难治性溃疡的疗效。方法23例患者首先采用直线偏振光近红外线照射8min,每日照射1次,后在高压氧环境下采用直线偏振光近红外线照射创面10次为1个疗程,根据治疗效果行第2个疗程治疗,并评价治疗效果。结果单纯直线偏振光近红外线治疗后,治愈率为47．8％;联合治疗后,治愈率为69．6％;总有效率为91.3％,且无副作用。创面有金葡菌感染的5例患者在照射后,有4例培养转阴。结论高压氧联合近红外直线偏振光照射对难治性溃疡有明显的疗效。     

极化心脏停搏液对成熟心肌细胞保护作用的研究

目的观察Na＋通道阻滞剂河豚毒素（TTX）极化心脏停搏液对离体成熟大鼠心肌细胞[Na＋]i、[Ca2＋]i的影响,探讨其对成熟心肌细胞的保护作用。方法成年Wistar大鼠心脏,用酶解法分离成具有搏动性的单个成熟心室肌细胞悬液,随机分成基础组、STH2组（对照组）和TTX组（实验组）,STH2组和TTX组分别应用St.Thomas II号停搏液和TTX停搏液处理,建立模拟缺血/再灌注损伤的停搏/复搏细胞模型,激光扫描共聚焦显微镜（LSCM）测定各组细胞不同时期的[Na＋]i和[Ca2＋]i。结果 TTX组和STH2组成熟心肌细胞复搏后[Na＋]i、[Ca2＋]i均明显高于基础组（P〈0.01）,但TTX组明显低于STH2组（P〈0.01）。结论极化心脏停搏液较去极化心脏停搏液能减轻成熟心肌细胞Na＋、Ca2＋超载,对成熟心肌细胞有较好的保护作用。     

参麦注射液联合极化液对大鼠复苏后脑组织的影响

目的探讨参麦注射液联合极化液对心肺复苏后脑保护的作用。方法建立成年雄性SD大鼠心脏骤停-心肺复苏模型,随机分为对照组（A组）、复苏组（B组）、极化液组（C组）、参麦组（D组）和联合用药组（E组）,每组8只。复苏后24 h进行神经功能评分,并观察脑组织细胞结构,测定脑组织含水量、丙二醛（MDA）含量、超氧化物歧化酶（SOD）及Na＋-Ka＋-ATP酶活力的变化。结果 B组脑组织含水量、MDA含量较各治疗组显著增高,SOD及Na＋-Ka＋-ATP酶活力减低（P〈0.05）,E组各项指标检测较C组、D组好（P〈0.05）、脑组织超微结构改变轻微。结论参麦注射液联合极化液对心肺复苏后脑组织有一定程度的保护作用。