Transcript Document

HISTOLOGY:
THE MICROSCOPIC STUDY OF BIOLOGICAL MATERIAL
PATHOLOGY: THE STUDY OF DISEASE and THE MORPHOLOGIC CHANGES
THAT OCCUR IN
INJURY, DEATH,
REPAIR, ADAPTATION:
ACCUMULATIONS, ATROPHY, HYPERTROPHY,
HYPERPLASIA, METAPLASIA
INFLAMMATION
NEOPLASIA
HISTOLOGY:
THE MICROSCOPIC STUDY OF BIOLOGICAL MATERIAL
Derivatives of the three germ layers:
Endoderm, Mesoderm, Ectoderm
---Epithelium
---Connective Tissue
---Neural
EPITHELIUM:
comprised of cells that cover the exterior surface of the body,
and line both the internal closed cavities of the body,
and those body tubes that communicate with the exterior
--alimentary, respiratory, genitourinary
Can be impervious (epidermis or bladder) , secretory (stomach),
absorptive (intestines), be a transport system(trachea),
or receive sensory stimuli (taste buds of the tongue)
Epithelium is attached to its underlying connective tissue by
basement membrane
SQUAMOUS AND TRANSITIONAL EPITHELIUM
Human skin
Mouse skin
BLADDER
Mouse skin
GLANDULAR EPITHELIUM
Small intestine with villi
Mucin stain showing goblet cells
Colon with NO villi
Mucin stain showing goblet cells
Epithelial cells (continued--mouse tissues)
Liver
Pancreas
Kidney glomerulus/tubules
Lung
CONNECTIVE TISSUES:
---CELLS:
-fibroblasts
-adipose cells
-undifferentiated mesenchymal cells
-cells of the hematopoietic system
Trichrome stain for collagen
---EXTRACELLULAR MATRIX:
-EXTRACELLULAR FIBERS:
-collagen fibers
-reticular fibers
-elastic fibers
Silver stain for supporting reticulin fibers
-GROUND SUBSTANCE :
-proteoglycans
-hyaluronic acids
- TISSUE FLUID
MUSCLE, CARTILAGE AND BONE
TYPES OF MUSCLE: Cardiac, Smooth, Skeletal
Cardiac: striations + central nuclei
Skeletal: striations + eccentric nuclei
Smooth:
central nuclei
Non-epithelial tissues (continued)
Bone/cartilage
Brain-hippocampus and ventricle
Spleen
Cerebellum
HISTOCHEMISTRY
IMMUNOHISTOCHEMISTRY
IN SITU HYBRIDIZATION
USE OF HISTOCHEMISTRY TO DETECT DIFFERENCES IN
BONE AND CARTILAGE FORMATION
USE OF HISTOCHEMISTRY TO DETECT DIFFERENCES
DETECTED ON ROUTINE H&E STAINS
H&E
TRAP stain
for osteoclasts
Use of AlcianBlue/PAS to detect differences in Mucin
content within Brunner’s glands of duodenum
USE OF HISTOCHEMISTRY TO DETECT INFECTIOUS
ORGANISMS
Gram’s stain to detect
bacteria in tissue (oil
immersion x1000)
Silver stain (GMS) to
detect presence of fungal
hyphae in tissue x200
MORE EXAMPLES OF HISTOCHEMISTRY
Luxol Fast Blue for myelin
Fontana-Masson for melanocytes
Folded artefact
Cracked tissue artefact
Knife mark + folded arterfact
HISTOLOGY:
THE MICROSCOPIC STUDY OF BIOLOGICAL MATERIAL
PATHOLOGY: THE STUDY OF DISEASE and THE MORPHOLOGIC CHANGES
THAT OCCUR IN
INJURY, DEATH,
REPAIR, ADAPTATION:
ACCUMULATIONS, ATROPHY, HYPERTROPHY,
HYPERPLASIA, METAPLASIA
INFLAMMATION
NEOPLASIA
CELL INJURY: reversible or
irreversible if prolonged
Due to: oxygen deprivation-ischemic ( no blood flow) ,
mechanical trauma (burns),
chemical agents (acetaminophen) ,
infectious agents, immunologic
reactions, genetic defects,
nutritional imbalances etc.
INTRACELLULAR ACCUMULATIONS:
fatty change of liver cells in alcoholism or
obesity, glycogen deposits in diabetes,
accumulation of pigments like iron after
hemorrhage
METAPLASIA: (one cell type is replaced by another cell type:
cigarette
smoking induced change of bronchial epithlelial cells to squamous,
Barrett’s esophagitis--where the squamous epithelium of the esophagus is
replaced by columnar epithelium)
CELL DEATH:
necrosis (occurs from the progressive degradative action of
enzymes on the lethally injured cells)
apoptosis: -programmed destruction of cells
during embryogenesis
-hormone dependent involution in the adult
- cell deletion in proliferating cell populations,
immune cells, tumors, etc.
HYPERPLASIA:
An increase in the number of cells in an organ or
tissue, which may then have an increased volume.
Physiologic hyperplasia: Proliferation of mammary glandular epithelium
at pregnancy, compensatory hyperplasia of the liver after partial
hepatectomy
HYPERTROPHY: An increase in size of cells and thus an increase in the
size of the organ
eg: physiologic hypertrophy of uterus during pregnancy, hypertrophy of the
cardiac muscle in hypertension or valvular disease, hypertrophy of skeletal
muscles due to heavy exercise
ATROPHY: a shrinkage in the size of the cells due to
-a decreased work load ( when a limb is immobilized in a plaster cast)
-loss of innervation
-diminished blood supply
-loss of endocrine stimulation
-aging
INFLAMMATION AND REPAIR
Is a protective response, where the
goal is to rid the body of the initial
cause of injury and the
consequences
ACUTE: relatively short duration.
There is an alteration of blood
vesels such that there is an
exudation of fluid and plasma
proteins, with an emigration of
leukocytes, predominantly
neutrophils, into the focus of
injury.
CHRONIC: is of longer duration
and is associated with the
accumulation of lymphocytes and
macrophages and allowing the
repair process to occur, using
angiogenesis and/ or fibrosis.
Hematopoietic cells
Erythroid
Megakaryocytes
Leukocytes
Myelo-monocytic
Lymphoid
Monocytes
Mac-1
B cells
Myeloid
Red blood cells
(rbcs)
T cells
B220
CD3
Plasma cells
dendritic cells
Granulocytes
macrophages
Gr-1
Neutrophils Eosinophils Basophils
(polymorphonuclear PMNs)
mast cells
F480
platelets
NK
cells
CD41
NEOPLASIA: new abnormal growth
A neoplasm “ is a abnormal purposeless mass of tissue, the growth
of which exceeds and is uncoordinated with that of normal tissues,
and which persists in the same excessive manner after cessation fo
the stimuli which evoked the change”
Tumor= swelling. Benign tumor -- no infiltration into surrounding
tissue. Malignant tumor = cancer
Cancer is the common term for all malignant tumors. Cancer derives
from the Latin term crab presumably because it “ adheres to any part
that it seizes in an obstinate manner like the crab”
Robbins and
Kumar
textbook of
Pathology
description
of the
process of
malignant
progression
and
metastasis
Benign tumors: fibroadenomas, polyps of the colon, lipomas
CARCINOMAS:
-Malignant tumors of epithelial cells
-well differentiated, moderately differentiated, poorly differentiated
-squamous carcinomas
- adeno-carcinomas
alveolar
papillary
tubular
(anaplastic, undifferentiated, large cell, small cell)
(hepatocellular carcinoma, cholangiocarcinoma)
SARCOMAS: Malignant tumors of supporting tissue
-chondrosarcomas--cartilage
-osteosarcomas--bone
-hemagiosarcomas--blood vessel
-gliomas (astrocytoma, glioblastoma)
-lymphomas
-melanomas
-rhabdomyosarcomas
-leiomyosarcomas
-fibrosarcomas
-seminoma, teratoma, etc.
Teratoma has multiple tissue types
IMMUNOHISTOCHEMISTRY
is an important adjunct to histopathologic evaluation
Epithelium: Keratins
--pan-keratin
and antibodies to keratins of different molecular weights
Supporting connective tissues:
--Vimentin--fibroblasts, blood vessels
--vWF, CD31 (PECAM)-- endothelial cells of blood vessels
Hematopoeitic tissues: CD45, B220, CD3, F480, Mac-1, Gr-1, CD41
Muscle: desmin, smooth muscle actin
Neural: GFAP, NeuN, F480/Mac-1, MBP, NSE, S100
Hormones: specific antibodies--insulin, casein, etc.
Germ cells: alpha-feto protein (teratomas)
Proliferation markers-Ki-67