Introduction to pathology Introduction to pathology Medical College Of Inner Mongolia University For Nationalities Medical College Of Inner Mongolia University For Nationalities

Introduction to pathology  The role of pathology in medicine  Pathology is the study of disease by scientific methods.  Pathology is a discipline bridging clinical practice and basic science;  pathologists are doctors who are concerned primarily with the study of disease in all it aspects, that is, causation diagnosis, pathogenesis, mechanisms, natural history, anatomic and biochemical features, progression, and prognosis

 The content and task of pathology The object of pathological study aim at diseases. What is disease? Disease may be identified as an abnormal variation in the morphological, structure and function of any part of body. In other words, a disease is a normal condition of body caused a loss of normal health (dis-ease)

 Each separated name disease is characterized by a distant set of features. including: Etiology: The cause of a disease Pathologenesis: The mechanism causing the disease Pathological and clinical manifestations: The structure and functional features of the disease Complication and sequelae: The second, systematic or remote consequence of a disease Prognosis: The anticipated course of the disease in terms of cure, remission, or fate of the patient Epidemiology: The incidence and population distribution of a disease

 Pathology focuses on four aspects of disease:  Its cause (etiology)  The mechanism of its development (pathogenesis)  The structural alterations induced in cells and tissues (morphology)  The functional consequences of the morphologic changes, as observed clinically.

 Pathology includes two major parts General Pathology: is the study of the basic principles of pathological processes involved in disease (e.g. congenital versus acquired diseases, inflammation, tumor, and degeneration); Systematic pathology: in the study of structure and functional abnormalities of a specific disease of body organs or system, such as respiratory system (lung cancer), digestive system (appendities) and so forth.

Clinical Pathology experimental Pathology autopsy (A) animal experiment biopsy (B) cell culture. cytology (C)  The methods of pathological research

 Clinical pathology Clinical pathology is studying a patient's illness which is based on the patient's history, morphological manifestation and make a diagnosis, and the treatment in clinical.

1. Autopsy Autopsy (necropsy and postmortem examination are synonymous) means to see for oneself. The autopsy rate has declined precipitously throughout the United States. The autopsy continues to have an important role. Determine the cause of death Make the accuracy of clinical diagnosis Education of medical students and clinicians Research into the causes and mechanisms of disease Gathering accurate statistics about disease incidence

Biopsy is often favored because it provides generous amounts of tissue for diagnosis and may itself afford sufficient surgical therapy for some tumors. frozen sections permanent sections 2.Biopsy

Cytology is used for both screening and diagnosing of lesions. This study of disease processes involves cell smears from various orifices (e.g., vagina, mouth, bronchus) of the fine needle aspiration (FNA) of any mass of lymph node. 3. Cytology All future clinicians should recognize that modern pathologists cannot operate in a vacuum, but must coordinate their impressions with the clinical situation.

 Experimental pathology Animal experiment The animal experimental methods are applied to replicate some models of human disease in order to investigate the etiology, pathogenesis, pathological change and the results of the disease. It is an important reference to human disease

2. Cell culture Cell cultures are widely used in research and diagnosis. They are an attractive medium for research because of the ease with which the cellular environment can be modified and the responses to it monitored. Diagnostically, cell cultures are used to prepare chromosome spreads for cytogenetic analysis.

Observation and New Technique of Morphology （一） Gross appearance: size, shape size, shape weight weight color color consistency consistency surface surface edge, section edge, section

（二） Histologic and cytologic observation: most common and basic formalin fixed → HE (hematoxylin and eosin) stained Hemangioma of ventrical wall

（三） Histochemistry and cytochemistry PAS → BM

（四） Immunohistochemistry 1. Ag-Ab specific reaction 2. Applications (1) Location analysis cytokeratin → cell membrane cytokeratin → cell membrane (2) Clinical diagnosis and distinguishing diagnosis of tumor histogenesis diagnosis of tumor histogenesis

Leiomyosarcoma Actin (+)

（五） Ultrastructural observation TEM (transmitting electron microscope) Filtering membrane

SEM (scanning electron microscope) Podocyte

（六） Flow cytometry (FCM) 1. One kind of cells → quantitative 2. DNA ploidy analysis 3. Protein nucleus acid → quantitative analysis analysis 4. Selection of collection of cells

（七） Image analysis (IA) Nuclei: diameter; circumference; area; Nuclei: diameter; circumference; area; volume; morphology volume; morphology （八） Laser scanning confocal microscope (LSCM) microscope (LSCM) aliving cell → observation in situ or aliving cell → observation in situ or development or quantitative development or quantitative

（九） Molecular biology technique 1. Polymerase chain reaction (PCR) 2. DNA sequencing 3. Biochip technique (1) Gene chip (DNA chip) (1) Gene chip (DNA chip) (2) Protein chip (protein microarray) (2) Protein chip (protein microarray) (3) Tissue chip (tissue microarray) (3) Tissue chip (tissue microarray)

Polymerase chain reaction (PCR)

History of pathology Autopsy → Organ pathology (1761) Autopsy → Organ pathology (1761) LM → Cellular pathology (1854) LM → Cellular pathology (1854) Ultrastructural pathology with the application Ultrastructural pathology with the application of EM (20 century 60s) of EM (20 century 60s) Immunopathology, Molecular pathology, Immunopathology, Molecular pathology, Genetic pathology, Quantitative pathology Genetic pathology, Quantitative pathology