pathophysiogy

• Breakdown or disorder of the human body’s
• functions

Development of disease

• study of all factors that may be involved in development of a
• disease.

• etiologic factors: biologic agents, physical forces, chemical
• agents, nutritional deficits or excesses person’s susceptibility, way in which
• pathogen enters body

• (Greek)
• diseases were caused by four humors: blood from heart, yellow bile from liver,
• black bile from spleen, phlegm from brain. Thought health came from exercise,
• moderate diet and resting when ill.

• the
• process of synthesizing RNA from a DNA template

•Error in genetic material


•Classified according to where they occur

• gladiators. Little dissection after his death for next 1400 years. Thought
• heart warmed the blood

• Italian. Master of dissection. Also
• described how body parts worked

• : English
• described circulation of blood which is pumped by heart. Also described blood
• pressure

• Dutch
• Developed a better microscope set the stage for cellular biology

• :
• English First vaccination. Injected pus from cowpox into arm of boy. This kept
• him from contracting smallpox

• did
• not invent Listerine! Thought that microbes caused infections. Washed wounds
• with carbolic acid

• promoted
• sanitation as a weapon against disease. Worked during the Crimean war in
• 1850’s. Was able to greatly reduce death rate from 40% of wounded to 2%.

• French
• studied fermentation and determined it was caused by microorganisms. Developed
• pasteurization to prevent souring of wine

• :
• German. identified the bacillus which caused anthrax. First microbe to be
• identified as a cause of disease

• German.
• Discovered X rays – could see internal organs without wounds or dissection

• established
• a nursing service for poor rural areas

• German
• discovered certain chemicals would damage microbes but not the human host. Used
• an arsenic compound to treat syphilis

• :
• English discovered penicillin would kill certain bacteria staphylococci. Didn’t
• go into production until the 1940’s (WW2

• isolated
• insulin and used it for treating diabetes

• :
• educate public to reduce fear of disease and bring about early diagnosis. No
• effective medicine until 1945. Before that: good nourishment, fresh air and
• rest.

• :
• first polio vaccine; used killed viruses died in 1995 U of Pittsburgh

• oral
• polio vaccine; used attenuated polio viruses died in 1993. U of Cincy

• developed
• first heart lung machine for use in surgery. Philadelphia

• :
• South Africa. first heart transplant. Washkansky survived the operation and lived for eighteen days. However, he succumbed to pneumonia
• induced by the immunosuppressive drugs he was taking. Next patient in 1968
• lived 19 months. One lived 12 years and one over 23 years.

• Many
• other advances.

The inner folding of mitochondria

• Space
• inside the inner membrane is called the Matrix. This is where many of the reactions of cellular
• respiration occur.

• Produces
• ATP

• is
• continuous with the nuclear envelope

• has
• ribosomes on outer surface
• Also will sequester large amounts of calcium in muscle cells – there it is
• called sarcoplasmic reticulum

• no
• ribosomes. Involved in lipid
• metabolism

Formed by Golgi Complex


Contain various enzymes

• Tay
• Sachs Disease

• occurs
• when cells are subjected to persistent, sub lethal stress

Cells become smaller

disuse



ischemia


denervation




nutrient starvation



poor endocrine stimulation



aging

• in
• a cast, paralysis, bed rest disuse
• atrophy. Mostly with muscle cells.
• Atrophy is reversible and when normal use returns, cells will return to
• original size.

• : inadequate blood
• supply. Especially
• dangerous for heart and brain

• usually
• affects brain cells and endocrine-dependent organs: gonads. Also heart

• poor
• intake, poor absorption or poor distribution to tissues

• most tissues depend on growth stimulating hormonal
• signals

Hypothalamus and pituitary stimulate many tissues

• Ex: breasts and reproductive organs in post menopausal
• women

• loss of
• nervous stimulation; paralysis – leads to disuse

•Cells get larger

• When
• part of organ or tissue is removed or becomes inactive ex kidney removal. Other
• one will become larger.

Increase in # of cells


Increased cell division

• One type of
• mature cell is replaced

• by another
• type
• example:
• Epithelium or mesenchymal tissue

Reversible

Deranged cell growth

• Once stress is removed, recover
• •Two main events:

•Hydropic Swelling


•Substance Accumulation

• :
• Na-K pumps malfunction and Na accumulates within the cell.

• This
• pulls water into cell (osmosis) and the
• cytoplasm is diluted. Mitochondria will become swollen.

• This
• can cause an entire organ to enlarge.

• in
• the cells. The can be harmful because the accumulations are toxic OR because
• they take up space needed for cellular functions.

• Extent
• of injury depends in part on the duration and severity of assault and in part
• on the prior condition of the cells.

• Well nourished and
• somewhat adapted cells may withstand injury better than poorly nourished or unadapted cells

•Excessive amounts of normal substances


•Accumulation of abnormal substances


•Accumulation of non-degradable substances


•Most accumulations are reversible

• these are often produced by the cells. With diabetes,
• neurons may take up too much glucose
• which is changed to SORBITOL – this pulls water into cell. Excess water
• interferes with impulse conduction.

• Pigments may accumulate – some accumulation is normal
• i.e. when we tan our skin accumulate melanin

: Lead, pigments, coal dust, silica dust

• Pigments
• from tattoos, and natural
• sources: bilirubin, lipofuscin (lipid rich age spot
• pigment) hemoglobin, ferritin. Melanin

• will
• get a blue lead line along the edge of the gums

• HYPOXIA
• - lack of oxygen

• -most
• common type of cell injury
• : Ischemia

shortage of O2 in air


obstruction of respiratory system



drop in # of RBC’s or hemoglobin


abnormalities

•Free radicals

• Free
• radicals are atoms or group of atoms that has an unpaired electron in its outer
• orbit. They are very unstable and will enter into chain reactions and form
• unstable bonds in important molecules in the cell. Will also produce more free
• radicals. Get a cascade of reactions which produce more free radicals

• Free radicals can denature proteins and inactivate
• enzymes, damage cell membranes, disrupt chromosomes.

• They are the
• byproducts of normal reactions – especially during hypoxia

They are also formed by exposure to UV light and X rays.

• Toxicity of some drugs and chemicals can be attributed
• to conversion of the chemicals to free radicals.

• Recent research links them to cardiovascular disease,
• diabetes mellitus, hypertension, macular degeneration and chronic heart failure
• among others

vitamin C



vitamin E



beta carotene, etc


also by enzymes

• inactivate
• free radicals. Vitamins C and E, beta carotene, albumin are some of the
• antioxidants.

• Some
• enzymes in the body will break them down and some will spontaneously decay.

• Formaldehyde
• Carbon tetrachloride

• an
• important chemical used widely by industry to manufacture building materials
• and numerous household products

• - High exposure can cause liver, kidney, and
• central nervous system damage

• . Coagulative necrosis
• Liquefactive necrosis
• Caseous necrosis
• Fat necrosis
• Gangrenous necrosis

• usually
• results from severe hypoxic injury with blockage of major arties. Common in
• lower leg and feet. Large mass of tissue is undergoing necrosis.

• Cellular
• destruction is caused when lipases (enzymes which break down lipids) break down
• triglycerides releasing fatty acids.

• Calcium, magnesium
• and sodium ions combine with fatty acids, making soaps

• commonly
• occurs as a result of a tuberculous pulmonary infection

• necrosis
• commonly results from ischemic injury to cells in the brain. Dead brain tissue
• is readily affected by liquefactive necrosis because
• brain cells have a lot of digestive enzymes and lipids and there is little
• connective tissue

• 1.occurs primary in the
• kidneys, heart and adrenal glands. Usually caused by severe ischemia or
• hypoxia.

• Coagulation occurs
• when proteins are in the cell are denatured

fallen apart.Normal replacement of worn out cells