PHLT 304 Exam 2/Quiz 2 Material Questions With Verified Answers

Circadian Rhythms are: - Answer -Physical, mental, behavioral changes that occur over each 24 hour period -Cyclical -Governed primarily by light/dark Biological Clocks: - Answer -Control these cyclic responses -Composed of proteins in almost all tissues Suprachiasmatic nucleus (SNS) - Answer -Overall master clock -Composed of ~ 20,000 nerve cells -Located in the brain & receives direct input from eyes -SCN controls production of melatonin (hormone that makes you drowsy) Disruptions of Circadian Rhythms: - Answer Jet Lag, Shift Work Irregular Circadian Rhythms linked to certain chronic health conditions: - Answer Obesity, diabetes, depression Circadian Rhythms - Answer -At night DNA and other repair systems are highest -Histamine levels are lowest at night -Immune System lower at night Effects of sleep loss - Answer -Changes in mood, memory, cognition -Increased risk of obesity: decreases leptin, making you hungry and want carbs, changes in growth hormone (fat to muscle ratio) -Linked to increased risk of Type 2 diabetes -Cardiovascular issues: Hypertension/high blood pressure -Depression HRQoL - Answer Health-related quality of life T2 DM - Answer Type 2 diabetes mellitus CVDs - Answer Cardiovascular diseases Sleep Loss - Answer -Increased accident and injury: 98,000 deaths in medical errors, >80 hours/week = 50% more likely to make a significant error, fatigue 70% more likely to be injured on job -Car Accidents: 20% of car accidents, loss of work or function at work -High economic costs: $63 bn in employer costs, $100 bn for sleep disorders Sleep Hygiene - Answer -Go to bed t the same time ever day, including weekends -Create a routine -Don't look at eDevices right before sleep What color light is most disruptive to sleep? - Answer Blue light Effect of light color - Answer -Blue wavelengths during day: boost mood, attention, reaction time -Blue wavelengths at night: powerful suppressor of melatonin -Red light: weakest suppressor of melatonin (best for night lights) -Exposure to bright light during day boosts alertness, mood and helps with sleep at night Sleep Disorders - Answer -Affect > 40 million Americans -60% of people do not get asked by doctors about sleep -20% of people actually discuss sleep with doctor Insomnia - Answer -Sleeplessness (trouble going to sleep or staying awake) -Chronic = sleeplessness at least 3 nights per week for a month -This is comorbid with depression and anxiety -Many possible relationships (chronic pain or illness, injury, stress, psychological issues, bad sleep hygiene) Functions of the Immune System - Answer -Protect from pathogens -Differentiate between self and non-self -Homeostasis Immune System: Organs - Answer -Lymph nodes, vessels, spleen, skin, various white blood cells, respiratory system, stomach & intestines Two systems of Immunity - Answer -Innate Immunity -Adaptive Immunity: Humoral (Antibody-mediated immunity), Cell-mediated immunity Innate Immune System includes: - Answer -Anatomic barriers (e.g., skin), Physiologic barriers (e.g., stomach acid), Phagocytic cells that engulf and destroy organisms, Inflammation: produces antibacterial activity & stimulates phagocytosis, Natural killer cells: cytotoxic action against tumor cells and some virus-infected cells Innate Immune System Is: - Answer -Present from birth, first line of defense against infection, rapid, & non-specific Adaptive Immune System: - Answer -Also called "acquired" or "specific" immunity, Slower than innate immunity, Involves development of immunologic memory (Immunologic memory is crucial to the success of a vaccine), Specific to a particular foreign agent, Antigen: molecule on foreign body that provokes immune response Two types of adaptive immunity that often work together: - Answer 1. Humoral (Antibody-Mediated) Immunity -Primary defense against extracellular organisms -When B lymphocytes (B cells) encounter an organism, they recognize parts of the antigens on the surface -Binding of antigen to B lymphocyte triggers the cell to transform into a plasma cell -Plasma cells make antibodies that are specific for the antigen that initiated their production -Plasma cell can make up to 2000 antibody molecules per second 2. Cell-Mediated Immunity -Primarily involves T lymphocytes (T cells) -These are derived from bone marrow & undergo differentiation in thymus ~Types of T cells: -Cytotoxic T cells (Tc or CD8 cells): destroy infected host cells, cancer cells, & transplanted cells -Helper T cells (CD4 cells): enable Tc and B cells by secreting cytokines -Suppressor T cells: blocks the actions of some other types of lymphocytes, to keep the immune system from becoming over-active Cytokine - Answer proteins that regulate the intensity and duration of immune response and mediate cell-to-cell communication Antibody functions: - Answer -Antibodies: proteins secreted into plasma to help eliminate foreign organisms ~Antibody functions: -Neutralize bacterial toxins -Neutralize viruses -Attach to bacteria promoting phagocytosis -Activate components involved in inflammatory response -There are multiple classes of antibodies produced by plasma cells (IgM, IgG, etc.) -If immune cells encounter the same organism in the future: memory cells that were formed the first time stimulate a much faster immune response Active Immunity - Answer -After exposure to a foreign organism, immune cells produce antibodies and memory cells -May occur following infection with organism -May also occur following vaccination -Memory cells are formedlong- term protection Passive Immunity - Answer -Involves the transfer of pre-formed antibodies to an individual -Ex: transfer of maternal antibodies to fetus in utero -Ex: injection of an individual with preformed antibodies -Done when an immunoglobulin product is available for that organism -No memory cells formed -short term protection until antibodies consumed/catabolized Inflammation - Answer -Body's response to injury, infection, and endogenous ailments -Part of your innate immunity -Non-specific -Rapid early response -Vascular response -Think blood flow Purpose of Inflammation - Answer -Neutralize or destroy foreign particles in body -Limit damage to tissues -Prevent spread of infection or damage to other tissues How Inflammation Happens - Answer -When activated, blood vessels dilate and blood flow increases -This brings clotting factors, histamines, neutrophils, and phagocytes to the area -Neutrophils attack and kill foreign invaders -Phagocytes engulf invaders and debris -Clotting factors help close the wound, making a matrix upon which scabs and skin may develop Symptoms - Answer -Warmth -Redness -Throbbing pain -Localized swelling -Loss of function (with severe swelling) -All caused by increased blood flow Complications of Acute Inflammation - Answer -Abscesses -Compartmentalized infection leading to necrosis (tissue death) -Causes ongoing tissue damage -May lead to sepsis - infection widespread through blood -Must be lanced (don't do this at home) Complications: Sepsis - Answer Sepsis -Extreme response to an infection that triggers a chain reaction throughout the body -typically caused by blood-borne infections that induce a wave of systemic inflammation -This acute inflammatory response can have severe effects, leading to tissue damage, organ failure and death -Every year in the US, > 500,000 people acquire sepsis and 40% of them die -Important cause of death in the US Chronic Inflammation: Causes and Cosequences - Answer Intestinal dysbiosis: perturbations in the composition of the gut microbiome relative to the composition of the gut microbiome in healthy individuals Stress triggers the sympathetic nervous system - Answer -Fight or flight -Governed by the neurotransmitter - adrenaline Some Stress is Good - Answer -Stress is good for helping you respond quickly to danger -Stress can motivate you in tests, interviews -Too much stress is not good Chronic Stress - Answer Leads to loss of sleep, tiredness, trouble concentrating, and a distracted immune system Neurodegenerative diseases: - Answer -Incurable debilitating conditions caused by progressive degeneration of nerve cells (loss of function and finally death) -Ataxias: movement problems -Dementias: impaired mental functioning ~Alzheimer's disease (most common form of dementia) ~Other dementias (there are many) Neurodegenerative disease examples - Answer • Alzheimer's disease • Vascular dementia • Lewybodydementia • Parkinson's disease (PD) • Amyotrophic Lateral Sclerosis (ALS) • Huntington'sdisease • HIV-related cognitive impairment • Multiple Sclerosis (MS) • Creutzfeldt-Jakobdisease Alzheimer's Disease - Answer •6th leading cause of death in the US •Social & financial costs: nearly everyone in the final stages of Alzheimer's needs constant care Alzheimer's Disease: Modifiable risk factors - Answer • Depression • Diabetes • Head trauma (severe or repeated) • Hearing loss • Alcoholism • Hypertension • Cardiovascular disease • Low levels of formal education • Obesity• Smoking• Social isolation RISK FACTORS WE CAN'T CHANGE: • Age • Gender (higher risk of Alzheimer's for women) • Genetics Primary Prevention of Alzheimer's - Answer • Stay active (physically and socially) • Keep fit • Healthy balanced diet • Engage the brain Secondary Prevention of Alzheimer's - Answer • Diagnosis • Check for underlying treatable conditions (all dementia), EX: Vitamin B12 deficiency • Awareness • Patient and caregiver support