Download - Cellular injury & adaptation
Cellular injury & adaptation.
ByDr Abiodun Mark Akanmode. CELL. A basic cell is bounded by a cell
membrane.
Within the cell is a nucleus containing chromatin, often condensed
at the periphery, along with larger clumps called chromocenters,
and in some cells a nucleolus into which RNA is concentrated. The
cytoplasm contains the cytosol and a variety of organelles,
including mitochondria that power the cell via production of ATP,
endoplasmic reticulum and ribosomes that synthesize new materials,
a Golgi apparatus, and lysosomes. What is the difference?
Testicular Atrophy. The testis at therighthas undergone atrophy and
is much smaller than the normal testis at theleft. Identify the
organ, what is the pathology here? Cerebral Atrophy. This is
cerebral atrophy in a patient with Alzheimer disease. The entire
size of the brain is reduced, but some parts are more affected than
others. Thegyriare narrowed and the interveningsulciare widened,
most pronounced toward the frontal lobe region. What is the organ?
What is he pathology here? Left ventricular hypertrophy.
This is cardiac hypertrophy involving theleft ventricle. The number
of myocardial fibers does not increase, but their size can increase
in response to an increased workload, leading to the marked
thickening of the left ventricle in this patient with systemic
hypertension. A B Identify the organ? What is the pathology here?
BENIGN PROSTATIC HYPERPLASIA.
This is an example of prostatic hyperplasia. The normal adult male
prostate is about 3 to 4 cm in diameter. The number of prostatic
glands, as well as the stroma, has increased in this enlarged
prostate seen in transverse section, and as a result, the entire
prostate has increased in size. The pattern of increase here is not
uniform, butnodular. This increase is in response to hormonal
action on the cells, but in this case is not a normal physiologic
process, but a pathologic process that could interfere with
emptying of the urinary bladder. Identify the slide? BPH. Here is
one of the nodules of hyperplastic prostate, with manyglands along
with some interveningstroma. The cells making up the glands are
normal in appearance, but there are just too many of them. Identify
the slide? What is the pathology? Columnar Metaplasia (Barrets
esophagus)
Metaplasia of the normal esophagealsquamous mucosahas occurred
here, with the appearance of gastric typecolumnar mucosa. Gerd is a
major risk factor for this pathology. If Barrets esohagus is not
treated the eventual outcome is adenocarcinoma of the esophagus.
Lipofucin accumulation.
Here is the centrilobular portion of liver next to a central vein.
The cells have reduced in size or been lost from hypoxia. The pale
brown-yellow pigment islipochromethat has accumulated as the
atrophic and dying cells undergo autophagocytosis Thymus undergoing
apoptosis. Apoptosis. In this fetal thymus there is involution of
thymic lymphocytes by the mechanism ofapoptosis. In this case, it
is an orderly process and part of normal immune system maturation.
Individual cells fragment and are consumed by phagocytes to give
the appearance of clear spaces filled with cellular debris.
Apoptosis is controlled by many mechanisms. Genes such as BCL-2 are
turned off and Bax genes turned on. Intracellular proteolytic
enzymes called caspases produce much cellular breakdown. What is
the organ here? What is the pathology? liquefactive necrosis.
Grossly, the cerebral infarction at the upper left here
demonstrates liquefactive necrosis. Eventually, the removal of the
dead tissue leaves behind a cavity. Liquefactive necrosis is
typical of organs in which the tissues have a lot of lipid (such as
brain) or when there is an abscess with lots of acute inflammatory
cells whose release of proteolytic enzymes destroys the surrounding
tissues. What is the pathology here? Fat necrosis This is fat
necrosis of the pancreas.
Cellular injury to the pancreatic acini leads to release of
powerful enzymes which damage fat by the production of soaps, and
these appear grossly as the soft,chalky white areasseen here on the
cut surfaces. Identify the organ? What is the pathology here?
Caseous or cheesy necrosis.
This is the gross appearance of caseous necrosis in ahilar lymph
nodeinfected with tuberculosis. The node has a cheesy tan to white
appearance. Caseous necrosis is really just a combination of
coagulative and liquefactive necrosis that is most characteristic
of granulomatous inflammation. Identify the organ here? What is the
pathology? Caseous necrosis in TB. This is more extensive caseous
necrosis, with confluent cheesy tan granulomas in the upper portion
of this lung in a patient with tuberculosis. The tissue destruction
is so extensive that there are areas of cavitation (cystic spaces)
being formed as the necrotic (mainly liquefied) debris drains out
via thebronchi. What is the organ? What accumulation is seen here?
Fatty liver aka hepatic steatosis.
Intracellular accumulations of a variety of materials can occur in
response to cellular injury. Here is fatty metamorphosis (fatty
change) of the liver in which deranged lipoprotein transport from
injury (most often alcoholism) leads to accumulation of lipid in
the cytoplasm of hepatocytes. Identify the organ? What is the
pathology here? Alcoholic cirrhosis. The liver injury with chronic
alcoholism leads to fibrosis and regeneration of the hepatocytes in
nodules. This firm, nodular appearance of the liver as seen here is
called cirrhosis. Muchas gracias al final.