1、.1Histology Introduction Yu Xiangmin (于向民）Department of Histology and Embryology.2Definition: A science: study normal micro-structure(& its related function of human body. 4 structural levels: Cell: the smallest structural & functional unit. Tissue(: groups of cells (similar in morphology or related
2、 in function)intercellular materials 4 types of fundamental tissue epithelium connective tissue muscular tissue nervous tissue .3 Organs:器官organizations of various kinds of tissues in particular ways & perform a specific function. System:系统formed by several function-related organs which together per
3、form a continuous physiological function. For example: digestive system .4.5Why do we study histology ?vTo complete the knowledge of human bodys structures-from gross to microscopicvBe able to understand how the different tissues function-the basis of physiologyvCan find the diseases only after the
4、normal is known-the basis of pathologyvIt is also a foundation of clinic sciencesfor a good doctor needed in future.6ight microscopy.7l reparationparaffin section preparation Specimen: as fresh as possible Fixation: fixative: formalin solution; purpose: to preserve the structural organization Dehydr
5、ation: replace the water in the tissue by alcohol Clearing: replace the alcohol by xylene Embedding: replace the xylene with melted paraffin Sectioning & mounting.8.9 Freezingcryostattainingothers:.10v Purpose:To make tissue section for observation.v H-E Staining: Hematoxylin:basic dye, bluish color
6、 Eosin:acid dye, pink color Basophilic:components stained with basic dye (H); bluish（nuclear chromatin) Acidophilic:components with an affinity for acidic dye (E); pink (cytoplasm & collagen fiber).11 Neutrophilic:do not stain with both basic and acid dyesArgyrophilia: those with an affinity for sil
7、ver, dark-brown color .12Fluorescent stainingshows the apoptosis in human HL-60 cells.13Electron Microscopy.14.15.16Diagrams of TEM.17 Sowing the 3 dimensional surface Architecture of cells and tissues Resolution: 5nm.18JEOL扫描电子显微镜扫描电子显微镜.19III. Histochemistry & Cytochemistry Reveal the chemical com
8、position in situ (e.g. proteins, a.a., nucleic acid, lipids, enzymes etc.) with chemical, biochemical methods. The product of chemical reaction should be insoluble / colored / electron- scattering, & be seen in LM or EM .20polysaccharide + HIO4 (hydroxyl group) (oxidise)Aldehyde group + Shiffs reage
9、nt (colorless) Purplish red depositorFor instance:vPAS(P(Periodic Acid Schiff) reaction: for manifesting polysaccharide .21PAS reaction in the goblet cell.22IV. Immunocytochemistry Based on antigen binds to specific antibody. Tissue section with Antigen + labelled antibody labelled Ag-Ab complexFluo
10、resceinlabellingenzyme labelling.23.24in situ hybridization (ISH) nucleic acid molecular hybridizationfragment of intracellular ene expression.25Expression of PSA and PSAmRNA in human prostate (histochemistry & ISH).26The method in learning histologyCombination of the 2 dimentional structure with 3 dimentional.27Combination of the theory with practiceCombination of the structure with functionConcern the dynamic change.28Questions for reviewvWhat is the H &E staining?vDescribe basophilic, acidophilic, neutrophilic?vWhat does PAS positive means?
