Exam 2 Flashcards
Characteristics of prokaryotes
Lack nuclear membrane
Function metabolically and reproduce
Complex cell wall
Characteristics of eukaryotes
DNA is enclosed in nuclear membrane
Cell membrane is complex
Lack cell walls
Three different shapes of bacteria
Cocci - found
Spirals
Bacilli - rods
Exotoxins
Produced by gram positive bacteria and diffuse through body fluids
Intefere with nerve conduction
Enterotoxins
Stimulate vomitting center and cause GI distress
Endotoxins
Produced in cell wall of gram negative organisms and are released after organism dies
Cause fever and weakness
Virion
When virus is extracellular
Three groups of microorganisms that have similarities to both viruses and bacteria
Chlamydiae
Rickettsiae
Mycoplasma
Rickettsiae
Gram negative bacteria that invade the host
Transmitted by insect vectors
Mycoplasma
Common cause of pneumonia
Lack cell walls so is not affected by many antimicrobial drugs
Characteristics of fungi
Single cells or chains of cells
Grow in warm and moist environment
Long filaments are hyphae
Mass of fungi is mycelium
Pathogenic fungi
Tinea pedis (athlete’s foot)
Candida (thrush)
Histoplasma (lung infection)
Characteristics of protozoa
Eukaryotic
Unicellular, motile, occur in a number of shapes
Pathogens usually parasites
Diseases caused by protozoa
Trichmonoas vaginalis - sexually transmitted infection (distinguished by flagella)
Malaria - causative agent is Plasmodium species which belongs to nonmotile group called sporozoa. Transmitted through blood sucking insects
Amoebas - can cause amoebic dysnentery; motile group that extends cytoplams and moves forward
Characteristics of helminth
Three stage life cycle: egg, larva, adult
Ova or larva ingested in contaminated food or water
Prions
Transmitted by consumption of contaminated tissues such as muscle or the use of donor tissues contaminated with the protein
Induces proteins within the brain to undergo abnormal folding and change shape
Example: Creutzfeldt Jakob
Areas of body that lack resident flora
Lungs, kidneys, bladder
Endemic
consistent occurring in a population
Epidemic
occurs outside the normal geographical range or in higher than expected numbers
Pathogenicity
Capacity of microbes to cause disease
Virulence
Degree of pathogenicity of a specific microbe
Virulence is based on
Invasive qualities
Toxic qualities
Adherence to tissue
Ability to avoid host defense
Disinfectants
Chemical solutions that are known to destroy microorganisms on inanimate objects
Antiseptics
Chemicals applied to living objects (body) that do not cause tissue damage. They reduce the number of organisms but do not destroy all of them
Incubation period
time between entry of the organism into the body and appearance of clinical signs of the disease
Prodromal period
time when the infected person may feel fatigued, lose appetite, or have a headache, “coming down with something”
Acute period
Infectious disease develops fully and clinical manifestations reach peak
Local signs of infection
Inflammation
Pus (purulent if bacteria; serous if virus)
Tissue necrosis
Swollen lymph nodes
Systemic signs of infection
Fever Fatigue Weakness Headache Nausea
Bactericidal
Drugs that destroy organisms
Bacteriostatic
Drugs that decrease the microbe’s rate of reproduction and rely on the host’s defenses to destroy the organisms
Warning signs of cancer (8)
- Unusual bleeding or discharge anywhere in body
- Change in bowel or bladder habits
- Change in wart or mole
- A sore that does not heal
- Unexplained weight loss
- Anemia or low hemoglobin (persistent fatigue)
- Persistent cough and hoarseness
- A solid lump, often painless
Three basic mechanisms of cancer
- Invasion - grows into adjacent tissue
- Metastasis - spread to distant sites by blood or lymph
- Seeding - spread of cells in body fluids or along membranes
Staging of cancer based on
Size of primary tumor
Extent of involvement of lymph nodes
Spread of tumor
Adverse effects of radiation
Bone marrow depression (leukopenia, thrombocytopenia, neutropenia)
Epithelial cell damage
Sterility
Adverse effects of chemotherapy
Hemorrhage (thrombocytopenia) Infections (neutropenia) Septicemia (tumors in GI tract) Pneumonia Skin infections Vomitting Epithelial cell damage Stomatitis
Definition of cancer cure
5 year survival without recurrence after diagnosis
Definition of remission
No clinical signs of cancer
Three families of endogenous opioids
Endorphins, enkephalins, dynorphins
Three types of opioid receptors
Mu, kappa, delta
Strong Opioid angonists
Used to treat severe pain
Have a high affinity for certain receptors and interact primarily with mu receptors
Opioid antagonists
Used to treat opioid overdose and addiction
Do not produce analgensia, but displace opioid agonist from opioid receptor and blocks any further agonist molecule
Effects of opioids on CNS (how they regulate pain)
Decrease ascending pain transmission
Activate descending pathways that reduce pain
How opioids affect synaptic transmission
Decrease neurotransmitter release from the presynaptic terminal and decrease excitable post synaptic neurons within key pain pathways
Opioid affect at pre-synaptic terminal
Activates G proteins that inhibit the opening of calcium channels on the nerve membrane
Opioid affect at the postsynpatic terminal
Opening of potassium channels which causes hyperpolarization and makes it more difficult to excite interior of cell
How opioids affect cAMP
inhibits adnenyl cyclase enzyme so decrease in synthesis of cAMP which regulates neurotransmitter release from pre-synaptic terminal
Clinical uses of opioids
Acute pain following surgery, trauma, MI
Tx of chronic pain in patients with cancer
Adverse effects of opioids
Sedative properties Euphoria Respiratory depression Cardiovascular problems - orthostatic hypotension GI distress - nausea and vomitting Constipation
Drug tolerance
Need to progressively increase the dosage of a drug to achieve a therapeutic effect when the drug is used for prolonged period of time
Physical dependence of drug
onset of withdrawal symptoms when drug is abruptly removed
Properties of NSAIDs
Decrease inflammation
Relieve mild to moderate pain
Decrease elevated body temp (fever)
Decrease blood clotting
Loading dose
A single large dose is given initially to establish analgesia; used to bring levels to therapeutic window
Demand dose
Amount of drug that is self-administered by the patient each time he or she activates the PCA delivery mechanism
Pathogenic effects of bacteria
Release toxic substances
Cause an immune response
Can lead to severe infections or death if patient’s immune system is compromised
3 basic mechanisms of antibacterial drugs
inhibition of bacterial cell wall synthesis and function
Inhibition of bacterial protein synthesis
Inhibition of bacterial DNA/RNA
How inhibition of bacterial cell wall synthesis works
Drugs cause inadequate production of peptidoglycan (present in cell walls)
Punch holes in bacterial cell walls
How bacteria inhibit protein synthesis
Bind to specific ribosomal subunits which blocks protein synthesis or causes ribosome to misread mRNA code
How bacteria inhibit DNA/RNA synthesis
Inhibiting production of folic acid
Block steps in folate pathways
Phases of cell cycle
G0 - resting stage G1 - pre-DNA synthesis phase S - DNA synthesis G2 - post DNA synthesis M - cell division or mitosis
Medications to treat severe pain
Hydromorphone
Morphine
Methadone
Meperidine
Medications to treat moderate pain
Codeine
Hydrocodone
Oxycodone
Adverse reactions of opioids
Severe/fatal respiratroy depression
Side effects of opioids
Sedation Respiratory depression Constipation Euphoria Nausea/vomitting Orthostatic hypotension
MOA of opioids that are strong agonists (treat severe pain)
Have a high affinity for mu opioid receptors (decrease ascending pain transmission and activate descending pathways that reduce pain)
MOA of opioids that are mild to moderate agonists (treat moderate pain)
stimulate opioid receptors but don’t have as high of an affinity
MOA of NSAIDs (besides acetaminophen)
Inhibition of prostaglandin and thromboxane synthesis by inhibiting the COX-1 and COX-2 pathways
Children with Reye’s syndrome should not take
Asprin
Adverse reactions of NSAIDs
Acute bronchospasm
Uticaria (itching)
Severe rhinitis
Cardiovascular shock
Common side effects of NSAIDs
GI distress
Can cause renal/liver problems
NSAID list
Aspirin Acetaminophen Ibuprofen Indocin Narpoxen Toradol Tolmetin
Antibiotics that inhibit cell wall synthesis
Penicillin
Ampicillin
Keflex
Antibiotics that inhibit protein synthesis
Garamycin
Erythromycin
Achromycin
Chloromycetin
Antibiotics that inhibit DNA/RNA synthesis
Cipro
Rifadin
Silvadene
INH
Antivirals that treat herpes infection
Acyclovir
Antivirals that treat influenza
Tamiflu
Symmetrel
Antivirals that treat HIV
Retrovir
Reyataz
Fuzeon
Antivirals that treat DNA/RNA viruses
Virazole
Antivirals that treat Hepatitis A and B
Interferons A
Antivirals that treat MS
Interferons Beta
Antivirals that regulate the immune response
Interferons Gamma
Antifunglas that affect the cell membrane
Monistat, vagistat
Amphocin
Nystatin
Sporanox
Antifunglas that inhibit mitosis
Fulvicin
Alkylating cancer drug
Thioplex
Antimetabolite cancer drug
FUDR
Methotrexate
Antineoplastic cancer drug
Blenoxane
Plant alklaloid cancer drug
Taxol
Sex hormones used for cancer tx
Prednisone Testosterone Estradiol Progestins Antiestrogens