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.