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Definition
◦ It is combination of two Latin words
◦ Pathos meaning disease
◦ Logos meaning study
Pathology is a branch of medicine that deals
with the nature of disease.
the study of the structural, biochemical, and
functional changes in cells, tissues, and
organs that underlie disease
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General pathology
◦ reactions of cells and tissues to abnormal stimuli
◦ reactions of cells and tissues to abnormal stimuli
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Systemic pathology
◦ alterations in specialized organs and tissues that
are responsible for disorders that involve these
organs
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Etiology (cause)
Pathogenesis (mechanisms of its
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Molecular and morphologic changes
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development )
(biochemical and structural alterations
induced in the cells and organs of the body)
Clinical manifestations (functional
consequences of these changes)
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Basic Molecular Biology
Basic Pathology*
Principles and practice of molecular pathology*
Molecular Biology of the Cell
Concepts in molecular biology
Concepts in genetics
Understanding molecular pathogenesis*
Clinical pathology*
Introduction to Bio-Informatics
Applied Comparative Pathology*
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Clinical proteomics and molecular pathology*
Integration of molecular and cellular
pathogenesis*
Molecular pathology of human diseases*
Molecular basis of diseases of pathology of
immunity*
Infection and host response*
Molecular mechanism of cell death*
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Modern Drug Discovery Technologies
Practical Histopathology and Mouse Models of
Human Disease
Microbial pathogenesis*
Modern Methods in Molecular Pathology*
Molecular Pathology of Cancer*
Biological Therapies
Molecular diagnosis of Infection
The human epigenome
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DNA Extraction RNA extraction
Blood group Test
Blood Sugar test
PAGE
Histopathology
ELISA
Immuno Histochemistry
Nature of Injurious
Stimulus
ALTERED PHYSIOLOGICAL STIMULI;
SOME NONLETHAL INJURIOUS
STIMULI
•Increased demand, increased
stimulation (e.g., by growth
factors, hormones)
•Decreased nutrients, decreased
stimulation
•Chronic irritation (physical or
chemical)
REDUCED OXYGEN SUPPLY;
CHEMICAL INJURY; MICROBIAL
INFECTION
Acute and transient
Progressive and severe (including
DNA damage)
Cellular Response
CELLULAR ADAPTATIONS
•Hyperplasia, hypertrophy
•Atrophy
•Metaplasia
CELL INJURY
Acute reversible injury
Cellular swelling fatty change
Irreversible injury ➙ cell death
Necrosis
Apoptosis
Nature of Injurious
Stimulus
Cellular Response
Metabolic Alterations, Genetic OR
Acquired;
CHRONIC INJURY
Intracellular Accumulations;
CALCIFICATION
Cumulative Sublethal Injury over
long life span
CELLULAR AGING
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Hypertrophy refers to an increase in the size of
cells, resulting in an increase in the size of the
organ.
Synthesis of more structural proteins
May be physiological
◦ Breast and uterus
◦ LVH
◦ Skeletal muscle
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Pathological
◦ Uterus under influence of estrogen secreted by ovarian
cancer
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Vascular supply
Diminished oxidative capability of the
mitochondria
Altered protein synthesis and degradation
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Hyperplasia is an increase in the number
of cells in an organor tissue, usually resulting
in increased volume of the organ
or tissue.
◦ Hormonal (breast, uterine muscles)
◦ Tissue loss (kidney, liver)
Mechanism of hyperplaia is by mitotic division
Normal myocyte
Adaptation
Reversible cell injury
Hypertrophied
myocyte
Cell death
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Atrophy is reduced size of an organ or tissue
resulting from a decrease in cell size and
number
Physiological
◦ Decreased workload
◦ Inadequate nutrition
◦ Aging
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Pathological
◦ Loss of innervation
◦ Loss of endocrine stimulation
◦ Diminished blood supply
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Increased degradation or decreased synthesis of
cellular proteins
Hormones (insulin, thyroid hormones,
glucodorticoids and prostaglandins)
Examples of atrophy
 Thymus atrophy
 Gonadal atrophy with age
 Starvation
 Disuse atrophy
 Denervation
 Diminished blood supply
 Pressure
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Metaplasia is a reversible change in which
one differentiated cell type (epithelial or
mesenchymal) is replaced by another cell type
an adaptive substitution of cells that are
sensitive to stress by cell types better able to
withstand the adverse environment
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Chronic irritation
Chronic inflammation
Vit A deficiency
Examples
Epithelial metaplasia
◦ Columnar to squamous metaplasia (trachea,
bronchi) .
◦ Atypical metaplasia.