How can you define diseases?
As a deviation from the normal structure, function or state of wellness in an organ, system or combination of those. Or as a deviation from the individual’s normal state of physical, mental, and social well-being, leading to a loss of homeostasis in the body.
What is homeostasis?
The maintenance of a stable internal environment regardless of the external changes (stimuli).
What needs to be done when significant changes occur and homeostasis can't be maintained?
An intervention; when a disease manifests.
What is pathophysiology?
The study of functional or physiologic changes in the body that result from the disease processes.
Why is a state of health difficult to define?
Because many factors can influence it, and may be different for each person. Ex. genetics, environmental influences.
When defining a "normal" limit for health indications like blood pressure and pulse, what do the values usually represent?
An average or range. They represent what is expected in someone, but aren't absolutes.
What is the difference between signs and symptoms?
Signs - objective
Symptoms - subjective (how you feel...)
Define these terms:
- gross level
- biopsy
- diagnosis
- etiology
- gross level: organ or system level
- biopsy: tissue specimens (excision of very small amounts of living tissue)
- diagnosis: identification of a specific disease through evaluation of signs and symptoms.
- etiology: about the causative (causes) factors of a disease such as congenital defects, genetic disorders, bacteria, environmental choices, etc.
When the cause of a disease is unknown it's ___.
idiopathic
When the disease is a result of an error of a procedure or treatment it's ___.
iatrogenic
Define these terms:
- predisposing factors
- prophylaxis
- prevention
- pathogenesis
- predisposing factors: factors that promote the development/acquisition of a disease and indicates high risk, ex. age, gender, sex, genetics,
- prophylaxis: measure to preserve health and prevent the spread of disease
- prevention: measures to prevent the spread of disease, ex. vaccinations, diet, lifestyle
- pathogenesis: describes the development of the disease or the events leading up to it
Define these terms:
- subclinical
- latent
- prodromal
- manifestations
- signs
- subclinical: disease is present but there are no obvious manifestations in the patient
- latent: a stage wherein no signs are evident, but the disease is present
- prodromal: the time of early development of a disease, but the signs are nonspecific, ex. throat is itchy, nose is a little stuffed, describes a fever about to come
- manifestations: the effects, the signs and symptoms of a disease
- signs: objective indicators of a disease from somebody other than the affected (the physician)
Define these terms:
- symptoms
- lesion
- syndrome
- remissions
- exacerbation
- symptoms: subjective feelings, such as pain or nausea
- lesion: specific local change in the tissue
- syndrome: a collection of signs or symptoms, usually affecting more than one organ
- remissions: a period where the manifestations subside, permanently or temporarily
- exacerbation: worsening of the severity of the disease
Define these terms:
- precipitating factor
- therapy
- sequelae
- convalescence/rehabilitation
- precipitating factor: a condition that triggers an acute episode
- therapy: treatment measures to promote recovery or the slow progress of a disease
- sequelae: unwanted outcomes of a condition, ex. paralysis from a stroke
- convalescence/rehabilitation: period of recovery and return to normal state
Define these terms:
- prognosis
- epidemiology
- epidemic
- communicable diseases
- prognosis: the probability for recovery or other outcomes
- epidemiology: the science of tracking the pattern or occurrence of disease
- epidemic: a high number of cases in an area
- communicable diseases: infections that can be spread from one person to another
What are the two recorded factors used to track the occurrence of a disease?
- Incidence: indicates the number of new cases within a period of time
- Prevalence: refers to the number of new and old or existing cases in a specific population and time period.
Disease can develop when cell structure and function ___ and homeostasis ___ be ___.
Disease can develop when cell structure and function change and homeostasis cannot be maintained.
What is the difference between hypertrophy and hyperplasia?
Hypertrophy - increase in the SIZE of the cells
Hyperplasia - increase in the number of cells
What is atrophy?
A decrease in the size of the cells.
What is metaplasia?
When a mature cell type is replaced with another mature cell type.
What occurs during dysplasia?
Cells vary in size and shape, and the mitotic rate is increased.
What kind of cellular changes are occurring in the picture?
Atrophy
What kind of cellular changes are occurring in the picture?
Metaplasia
When cells self-destruct, where do they disintegrate into?
Vesicles called apoptotic bodies.
What is necrosis?
Cell death; not a programmed event like apoptosis.
What are some causes that may lead to cell death/injury?
- ischemia
- radiation
- bacteria
- parasites
Injury of cells in the body can occur in numerous ways:
- ischemia
- excess heat or cold
- radiation
- mechanical damage (pressure or tearing)
- bacteria
- viruses
- parasites
- imbalance of fluids or electrolytes
How does an oxygen deficit affect the health of cells?
Because it may interfere with energy production in the cell. It leads to the loss of the sodium pump, which increases the sodium in a cell --> swelling (water follows salt into the cell). Anaerobic metabolism will build up in the cell, leading to a decrease in pH and a ^ of lactic acid.
How do infectious diseases affect cell health?
It can damage it by some of its actions. Some can cause pyroptosis (lysis in the cell by the release of enzymes into the tissue --> inflammation).
Describe the changes in a cell that lead to the following:
a. loss of function
b. necrosis
Restricted oxygen flow affects ATP production > eventual loss of function in the cell. After a long period of time the cell will undergo necrosis.