Week 1: Intro To Pathophys & Genetic Disorders Flashcards
Physiology
Study of the functions of the body
Pathology
Study of structural/functional changes; from pathos (suffering);
Morphology
Fundamental structure/function of cell/tissue
Histology
Study of cells and extra cellular matrix
Lesion
Pathological abnormality in tissue which can be seen and sampled
Pathophysiology
Changes that occur with injury/disease; from cellular to total body function
Disease
an interruption, cessation or disorder of body system(s) or organ structure(s) An atomic alterations are identified Etiology agent(s) are often recognized
Etiology
Describes how a disease process gets set into motion
The “cause” of the disease (as between smoking and lung cancer)
Disorder
An abnormality of function that has not yet been classified as a “disease.”
Pathogens is
Describes how a disease process evolves
The sequence of cellular/tissue/organ events that take place
Clinical Manifestations
Evidence of the disease; related to the primary change or the body’s attempt at compensation
Signs - objective; local vs systemic
Symptoms - subjective; complaints
Syndrome - a compilation of signs and symptoms that are characteristic of a specific disease
Diagnosis
Designation (naming) of the altered health issue
Requires H&P and review of findings
Assessment of the data provides for the differential diagnosis
Clinical Course
Evolution of the disease or disorder Acute, sub-acute, chronic Complication Prognosis Natural history
Epidemiology
Study of disease occurrence (tracking, transmission) in populations
Incidence - the number of new cases in the at risk population during a specific time period
Prevalence - a measure of all the existing disease cases at a point in time
Morbidity
A diseased state (I.e., altered body system or organ structure/function)
Mortality
State of being mortal…causing death
Gene
Basic unit of heredity, codes for a protein
Allele
A variant of a gene sequence - since cells have two copies of each chromosome (one inherited from mother and one from father) a person can be:
Heterozygous at any given gene locus (the two alleles are different)
Homozygous the two alleles are the same
Dominant allele
An allele that is phenotypically expressed when present in either homozygous or heterozygous condition (I.e. the two alleles can be the same or different but express the same phenotype)
Recessive allele
An allele that is phenotypically expressed only when present in the homozygous condition (I.e. the two alleles are the same)
Phenotype
Outwardly apparent physical and biochemical attributes
Genotype
Unique genetic makeup. Result of the 23 maternal and 23 paternal chromosomes uniting at conception
Disease - seven contributing factors
1 - Genetic
2 - Social determinants (poverty, environment, education, employment, social status)
3 - Adverse childhood experiences
4 - Micro-organisms
5 - Trauma due to accidents, violence
6 - Environmental hazards: toxins/exposures
7 - Lifestyle factors and behaviors (diet, physical activity, sexual behavior, smoking, seat belts, bike helmets, sunscreen….)
What are the three most prevalent diseases?
1 - Heart disease
2 - Cancer
3 - Chronic lower respiratory diseases
Describe the relationship between homeostasis and allostasis.
Homeostasis - remaining stable, systems in balance, “set point” (body temp, pH)
Allostasis - Ability to successfully adapt to challenges/stress (nervous, endocrine, paracrine systems) re-establishes “homeostasis” or balance in response to stressors.
Allostatic overload
“Cost” to body’s organs and tissues for an excessive or I effectively regulated allostatic response; effect of “wear and tear” on the body. Part of disease; cortisol, catecholamines, cytokines
How does allostatic overload contribute to disease?
An example is cortisol release in response to stress. The hypothalamus is stimulated to produce corticotropin releasing hormone. CRH stimulates the anterior pituitary to produce ATCH (adrenocorticotropic hormone) which travels through the bloodstream to the adrenal glands which sit on top of the kidneys. When ACTH makes its way to the adrenal glands, it stimulates a specialized region on the outer shell of the adrenal gland, the cortex, to synthesize cortisol. The precursor to cortisol is cholesterol. When cortisol is secreted it induces diverse reactions in the body. Cortisol causes skeletal muscle to break down it’s proteins. It liberates amino acids from skeletal muscle which enter the blood stream and circulate to the liver. They enter into the liver and cause it to produce more glucose from those amino acids or gluconeogenesis (new glucose production from a non-carbohydrate source). It also impairs the ability of glucose to be taken up into the skeletal muscle because there are insulin dependent take up mechanisms. The glut4 transmitter is inhibited by cortisol and glucose can’t be taken up into the muscle and builds up in the plasma. This is a precursor to diabetes and can turn into full blown diabetes. Cortisol also goes to adipocytes and causes the fatty acid chains to start to get cleaved in a process called lipolysis. Those fatty acids also get released into the blood and get metabolized in the liver. Breaking down fat, breaking down proteins and glucose is being formed in the liver from these other precursors which again gets secreted into the blood. It also increases catecholamines which causes vasoconstriction. When cortisol goes up there is an inhibitory feedback loop to the hypothalamus and pituitary to stop producing it. This works only as long as the body is not in allostatic overload.
Structure function inter-relationship
The structure of cells in your body affects its function. (I.e. the skull protects the brain) Function also affects structure - I.e. use it or lose it. (Muscles atrophy when not used, bones de-mineralize) which effects the structure. Pathophysiology is a mismatch between the two. Transcription factors determine the mRNA that get made. MiRNA’s can come and inhibit the ability of mRNA to make proteins.
