Exam 4 Flashcards
(131 cards)
1
Q
Define Pathology.
A
Study of disease
2
Q
Define Pathogen.
A
Disease causing agent
3
Q
Define Etiology.
A
Cause of disease
4
Q
Define Pathogenesis.
A
Manner in which the disease develops
5
Q
Define Infection
A
Invasion of body by pathogens
6
Q
Define Disease.
A
Infection causes a change in state of health (abnormal state)
7
Q
When does normal microbiota initially develop?
A
Formed at birth
8
Q
Where and how are normal microbiota initially introduced into the body?
A
As the baby leaves the birth canal, as the baby eats and breathes
9
Q
Define Normal Microbiota.
A
Microbes that colonize the body without causing disease
10
Q
Where does normal microbiota get nutrients?
A
Secretory products of cells, body fluids, dead cells, food in gastrointestinal tract
11
Q
Name 3 physical and chemical factors that affect normal microbiota.
A
pH
temperature
oxygen
12
Q
List 5 factors that alter the number and types of normal microbiota from one person to another.
A
a. age
b. Diet (nutrients)
c. Living conditions
d. occupation
e. Personal hygiene
13
Q
Define Symbiosis.
A
Relationship between normal microbiota and host
14
Q
Define Commensalism and give 1 example.
A
One organism benefits and the other is unaffectedEx. Corynebacterium inhabits the eye and lives on dead cells
15
Q
Define Mutualism and give 1 example.
A
Both organisms benefit
Ex. E.coli in large intestine synthesize vitamin K
16
Q
Define Parasitism and give 1 example.
A
One organism benefits and the other is harmed
Ex. any virus
17
Q
Define Opportunistic pathogen and give 1 example.
A
Pathogen that can cause disease if conditions change
Ex. E.coli can become harmful if it is in bladder, lungs, spinal cord
18
Q
List Koch’s Postulates
A
a. The same pathogen must be present in every case of the disease.
b. The pathogen must be isolated from the diseased host and grown in pure culture.
c. The pathogen from the pure culture must cause disease when it is inoculated into a healthy, susceptible laboratory animal.
d. The pathogen must be isolated from the inoculated animal and must be shown to be the original microbe.Classifying Infectious Diseases
19
Q
Define Symptoms.
A
Changes in body function
2 Examples:
Pain and malaise
20
Q
Define Signs.
A
Can be observed and measure
4 Examples:
Lesions, swelling, fever, paralysis
21
Q
Define Communicable disease.
A
Disease that spreads quickly from one host directly or indirectly
5 Examples:
Chickenpox, measles, genital herpes, typhoid fever, tuberculosis
22
Q
Define Contagious disease.
A
Easily spread from one person to another
2 Examples:
Chickenpox and measles
23
Q
Define Noncommunicable disease.
A
Not spread from one person to another
1 Example:
Tetanus
24
Q
Define Endemic disease.
A
Disease constantly present
1 Example:
Common cold
25
Define Epidemic disease.
Many people in a given area acquire a disease in a short period of time
1 Example:
influenza
26
Define Pandemic disease.
Epidemic that is worldwide
2 Examples:
Influenza, AIDS
27
Define Acute disease.
Develops rapidly but lasts a short period of time
1 Example:
influenza
28
Define Chronic disease
Develops slowly but is recurrent or lasts a long time
3 Examples:
Mononucleosis, tuberculosis, hepatitis B
29
Define Latent disease.
Microbe remains inactive but later becomes active to produce symptoms
1 Example:
Shingles—varicella zoster (virus)
30
Define Local Infection.
Invading microbes are limited to a small area
2 Examples:
Boils and abscesses
31
Define Systemic infection.
Microbes spread throughout the body
Example:
Measles
32
List 4 predisposing factors that would make the body more susceptible to
disease.
a. gender
b. Genetic background
c. Inadequate nutrients
d. age
33
Define reservoir of infection.
Source that provides a pathogen with adequate conditions for survival and multiplication
34
List 3 reservoirs of infection.
a. human
b. animal
b. nonliving soil and water
35
Define carriers.
Person that harbors pathogen (without showing signs of illness) and can transmit them to other
36
List 3 diseases that human carriers spread.
a. AIDS
b. gonorrhea
c. typhoid fever
37
List 2 diseases transmitted by animals.
a. rabies
| b. lyme disease
38
List the two major nonliving reservoirs of infection.
a. soil
| b. water
39
Name 2 microbes that from nonliving reservoirs that can cause infections.
a. Clostridium tetani
| b. Clostridium botulinum
40
Define Contact Transmission.
Spread of agent of disease by direct, indirect, droplet
41
Give 3 examples of direct contact (person to person) transmission.
Touch, kissing, sexual intercourse
42
Give 3 examples of illnesses causes by direct contact transmission.
Common cold, hepatitis A, STD, measles
43
Define Indirect contact transmission.
Nonliving objects
44
Define Fomite.
Nonliving objects
3 Examples of fomites:
Needles,tissues, bedding
45
Give 3 examples of illnesses caused by fomites.
HIV (needles), tetanus, hepatitis B
46
Define Droplet transmission.
Mucus droplets travel less than one meter
3 Examples:
Cough, sneeze, laugh
47
Give 3 examples of diseases spread by droplet transmission.
Influeza, pneumonia, whooping cough
48
Define Vehicle of transmission.
Transmitted by food, water, air, blood, drugs, body fluids
49
Define Vectors.
Animals that carry pathogens
50
Define Nosocomial Infection.
Hospital-acquired infection
51
Nosocomial infections are the result of 3 factors:
a. Microbes in hospital environment
b. Compromised status of host
c. Chain of transmission in the hospital
52
According to the CDC, handwashing is the single most important
means of preventing the spread of infection.
53
CDC reports that on average, health care workers wash their hands before interacting with patients
40% of the time.
54
Define Epidemiology
Science that studies when and where disease occur and how they are transmitted
55
17. List the 4 mechanisms of which bacteria become resistant to chemotherapeutic agents.
a. destruction or inactivation of drug
b. prevention of penetration of target site
c. alternation of drug target site
d. rapid ejection
56
List reasons why antibiotics are no longer effective (human causes).
Misuse, dose regimen too short, poverty, overprescribed
57
Ciproflaxin (nalidixic acid)
- inhibits DNA synthesis
| - used to treat Anthrax, UTI’s, pneumonia
58
Linezolid (Zyvox)
- developed in 2001
- 1st new class of antibiotics in 25 years
- inhibit protein synthesis (50S subunit of ribosome)
- treats gram positive bacteria
- used to combat MRSA
59
Sulfoamides
- also called sulfa drugs
- inhibits the synthesis of metabolites
- first synthetic drugs created
- used to treat UTI
60
Erythromycin
- inhibits protein synthesis
- treats gram positive bacteria
- used to treat pneumonia, strepto and staphylo cocci infections
61
Rifampin
- inhibits nucleic acid synthesis
| - used to treat tuberculosis and leprosy
62
Tetracycline
- produced by Streptomyces
- inhibits protein synthesis
- used to treat gram positive and negative bacteria and can penetrate body tissues
- used to treat urinary tract infections (UTI), pneumonia, and chlamydial infections
63
Bacitracin
- derived from Bacillus
- inhibits cell wall synthesis
- used to treat gram positives such as staphylococci and streptococci
- applied topically
64
Cephalosporin
- usually given orally
- inhibits cell wall synthesis
- used to treat gram negative bacteria
65
Semisynthetic penicillin
- chemically modified the mold Penicillium
- broad spectrum of activity
- inhibits cell wall synthesis
- used to treat gram negative and gram positive
- Examples: amoxicillin and ampicillin
66
Natural penicillin
extracted from the mold Penicillium
- narrow spectrum of activity
- inhibits cell wall synthesis
- used to treat staphylococci and streptococci
- shouldn’t be taken with acidic foods because they will decrease its effectiveness
- susceptible to penicillinases
67
Define antimicrobial drugs.
Class of chemotherapeutic agents used to treat infectious disease
68
Define broad-spectrum of activity.
Affect gram positive and gram negative bacteria
69
Define spectrum of activity.
Range microbes that antibiotics affect
70
Why is it difficult to treat viral infections?
The virus is in our cells and we don’t want to harm our cells
71
Why is it difficult to treat fungal or protozoan infections?
They are eukaryotic cells and so are humans
72
Name 3 ways eukaryotic and prokaryotic cells differ.
a. cell wall
b. ribosome
c. metabolic reactions
73
Which is easier to develop drugs against prokaryotic or eukaryotic cells and WHY?
Prokaryotic because we are eukaryotic and we don’t want to damage our cells
74
Which type of bacteria (2) produces most antibiotics, which molds produce most antibiotics?
Streptomyces and Bacillus
Penicillium and Cephalosporium
Spectrum of Antimicrobial Activity
75
Are all antibiotics that are discovered used in treating disease, explain?
No, toxic to humans
76
Where was the organism first isolated from a moldy cantaloupe bought?
Peoria, IL
77
Define antibiotic.
Substance produced by microbes that inhibit growth of another microbe
78
What bacterium was first noticed to be inhibited by Penicillium notatum?
Staphylococcus aureus
79
What is Penicillium notatum?
Mold
80
Who discovered Penicillium notatum?
Alexander Fleming
81
Who coined the term “chemotherapy”?
Paul Ehrlich
82
How do antimicrobial drugs kill microbes?
Interfere with growth
83
Penicillin
- 50 chemically related antibiotics
- different based on the chemical side chains
- produced naturally or semisynthetically
- inhibit cell wall synthesis
84
what is pathogenicity?
ability to cause disease
| depends on ability to invade, multiply, and evade host defenses
85
what is virulence?
degree of pathogenicity
86
pathogen?
disease causing agent
87
host?
where pathogen lives
88
infeciton
growth of the microbes on a host
89
why do micbrobes want in?
animals provide favorable environment
- rich in organic food
- maintain Temp and pH
90
what are portals of entry?
where pathogens enter
| ex. mucous membrane
91
types of mucous membrane for POE?
resp. tract
gastrointestinal tract
urogential tract
92
what is things to know about resp. tract POE?
enter by inhalation
most common POE
Ex. common cold, pneumonia, strep throat, TB, influenza, measles, and chicken pox
93
what are things to know about the gastro intestial tract POE?
enter by food or water, contaminated objects
| Ex. Hepititis A, typhoid fever, and food poisoning
94
what are thing to know about the urogential tract POE?
transmitted sexually
| Ex. HIV, Genital warts, herpes, and gonorrhea
95
what is the skin POE?
prime target for pathogen cant be penetrated unless its injured
96
what is the parental route POE?
when microbes enter injured skin or mucous membrane
| Ex. injection, bites,cuts, surgery, and burns
97
what is the perfered POE?
pathogens has to enter body in a certain way in order to cause disease
Ex.Clostridium tetni must enter though punctured skin to cause tetanus
98
what is the number of invading microbes?
more microbes present the greater the chance disses happens
LD50
ID50
99
what is LD50
lethal dose ( dose required to kill 50% of test animals)
100
whaat is ID50
infectious dose (dose required to produce infection in 50% of test animals)
101
what is adhesion?
once pathogens are inside host they attach to tissue
102
how is adhesion accomplished?
ligands or adhesion(fimbrae) which bind to receptors on the host's cell
103
if adhesion or receptors are altered
then infection can be prevented
104
What are examples of adherence
S. mutans (cause cavities) attaches to surface of teeth by glycocalyx
105
what are the pentration of Host defense- capsules
glycocaylx around cell wall prevent phagocytosis
| Ex. Streptococcus pneumonia and Bacillus anthraets
106
what are the cell wall componets of penetration of host defense?
m protien
| mycolic acid
107
what are M proteins
heat and acidic resistance protein prevents phagocytosis
| Ex. Streptococcus pyogens (strep throat)
108
what is mycolic acid
waxy lipid in cell wall prevents phagocytosis
| Ex. myobacterium tuberculosis (TB)
109
what are the enzymes in part of pentration of host defenses?
```
leukocidin
collagenase
coagulase
hyalurondinase
hemolysin
```
110
what is leukocidin?
destorys leukocytes
111
what is collagenase
destroys collagen
112
what is coagulase?
coagulates fibrinogens
| Ex. staphylococcus aureus (staph infection)
113
what is hyaluronidase?
digest hyaluronic acid (host cell together)
| Ex. streptococcus pyogenes (Flesh Eating)
114
what is hemolysin
the lyse RBC
115
what are the types of hemolysin?
alpha, beta, and gama
116
what is alpha hemolysin?
partial breakdown of hemoglobin adn produces green color around colonies
Ex. S.Mitis and S. salivarius (normal microbiota)
117
what is beta hemolysin?
complete breakdown of hemoglobin and produce clear zone around colonies
Ex. S.pyogenes (strep throat and scarlet fever)
118
what are gama hemolysin?
no breakdown of hemoglobin
| Ex. S. epidermis (normal microbiota)
119
what are the four ways damage to cell wall can occur?
1. use host nutrients
2. direct damage (lyse host cell)
3. toxin (poisouns substance)
4. induce hypersensitivity
120
what is toxigenicity?
ability to produce toxin
121
what is toxemia?
presence of toxin in blood
122
what is some toxin info?
can be transported by blood or lymph
can inhibit protein synthesis, destroy blood cells, damage blood vessels, and disrupt NS function
40&% of all toxin cause damgae to cell membrane of hos
123
what symptoms do toxin cause?
fever. shock, diarrhea, and cardiovascular problem
124
what ate the two types of toxins?
Endotoxin and Exterotoxins
125
whar are exotoxins
toxins relase directly inot the blood system
made of proteins
mainly gram positive
produce specific disease symptoms
126
what are the types of extotoxin?
neurotoixin
enterotoxin
cytotoxin
127
what is neurotoxin
attack nerve cells
| Ex. E. clostridium tetani (uncontrolled muscle contrations0
128
what is enterotoxin?
affects gastrointestinal tract
| Ex. E. Stapholococcus aureus ( food poisoning)
129
what is cytotoxin?
lyse host cell
| Ex. E. closridium perfringens (gas gangrene)
130
what are endotoxin?
toxin produced as part of cell wall and released when cell is damaged
gram negative
in LPS layer
antibiotic can worsen it
131
what do all endotoxin produce as symptoms?
chills, fever, weakness, aches, possible shock
| but in varying degrees
