Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PATHOBIOLOGY BMS106 > path terms > Flashcards

path terms Flashcards

1
Q

pathogenesis

A

the pathological mechanism that results in clinically evident disease e.g. the way in which the interaction between M. tuberculosis and the host immune system produces the caveating granulomatous lesion of TB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

non sense mutation

A

a single nucleotide change in which theDNA base pair change leads to a stop codon being present and a premature chain termination occurs during translation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

missense mututtion

A

point mutation where a single nucleotide change results in a codon that codes for a different amino acid e.g. in sickle cell anaemia the mutation change A to T and thus glutamic acid to valine (in a beta chain polypeptide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

null mutation

A

completely inactivates the function of the gene and the encoded product

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

frameshift mutation

A

may be a single nucleotide addition or deletion- altering the frame read by the ribosome to translate mRNA sequence downstream of mutation so ribosomes can still synthesise a poylpeptide chain (with a triplet code) i.e. a protein is still made
BUT
the protein will have an altered or abnormal function
due to the part encoded by the gene beyond the mutation having the wrong sequence of amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

examples of Mendelian inheritance

A

huntingdon’s chorea (disease)
Haemophilia
Brachydactyly (shortening of fingers and toes)
Alkaptonuria (black urine/bone disease)- can’t process phenalylaline and tyrosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

cancer is caused by

A

dominant, gain of function mutations in proto- oncogenes

or recessive loss of function mutation in tumour suppressor genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

proto gene function

A

to regulate cell proliferation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Duchenne Muscular dystrophy gene

A

the DMD gene is encoded on the x chromosome.
so females are either unaffected (not carrying any mutant allele) or a carrier (possessing a mutant allele but not affected)
Males, if they inherit a mutant allele in their X chromosome they will be affected due to their NOT possessing a normal coy of the gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

single gene disorders

A

are due to abnormal structure and are inherited in mendelian fashion

whereas abnormalities of chromosome number are not inherited normally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

imprinting

A

silences genes and occurs to some genes during gametogenesis so that either only the father’s or other’s allele will be expressed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

common disorders of imprinting

A

pradar-willi syndrome
angelman’s syndrome
beckwith-wiedemann syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

pyknosis

A

clumping of the nuclear chromatin (due to decrease in PH in cell from anaerobic metabolism)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

characteristics of HIV

A

HIV are retrovirurses that are characterised by being enveloped and containing 2 copies of a single-stranded RNA genome. The mature virus also contains enzymes such as reverse transcriptase, integrase and a protease. The virus also posses in it’s envelope proteins (gp120 and gp41) that enable the virus to bind to CD4 and its co-receptor CCR5 and effect entry into T-helper cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Hypertrophy

A

increase in cell size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Hyperplasia

A

Increase in cell number (in tissues that can divide or have abundant Stem cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Metaplasia

A

Change in cell differentiation (replacement of one mature cell type with another mature cell type).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Dysplasia:

A

Change in cell differentiation (replacement of one mature cell type with another LESS mature cell type) – tends to be disordered.
presence of abnormal cell type in a tissue - precancerous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

examples of tumour suppressor genes

A 
Rb
p53
WT-1
ptc
BRCA-1
Apc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

neutrophils

A

most abundant WBC
pus made of these
self destruct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

macrophages

A

derived from monocyte WBC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Natural killer cells

A

can kill own cells if become infected with virus or become cancerous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

MHC

A

major histocompatibility complex I
normal healthy cells have this protein on it’s surface
infected cells can’t produce these

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

MHC

A

major histocompatibility complex I
normal healthy cells have this protein on it’s surface
infected cells can’t produce these

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

HIV

A

enveloped virus
2 copies of single stranded RNA genome
binds to chemokine receptors present on macrophages and T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

forms of genetic medallion inheritance

A

autosomal recessive
autosomal dominant
X linked

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

examples of autosomal recessive diseases

A

cystic fibrosis, alkaponuria, sickle cell anaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

examples of autosomal dominant diseases

A

hunting tons disease, brachydactyly, aniridia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

examples of x linked diseases

A

duchenne muscular dystrophy, haemophilia, x lnked mental retardation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

sickle cell anaemia

A

missense mutuation glu-val

single point mutation in the codon for aa 6 in the B global subunit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

aniridia

A

loss of iris

deletion of single point mutation in one cope of PAx6 gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

indentification

A

genes can be identified purely on the basis of their choromosomal position without prior knowledge of the functions of their proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

obligate pathogens

A

can only survive on host (usually specific to host species)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

facultative pathogens

A

present in environment (reservoirs) waiting for host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

opportunisitic pathogens

A

normally benign but cause disease in compromised host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

cancers can be linked to inflammation

A

1) directly- due to organisms that modify and mutate DNA
2) indirectly- through mechanisms that provoke the release of reactive oxygen species by inflammatory cells, causing DNA damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

HIV

A

infects and destroys the CD4+ cells that are at the heart of the immune system
CD4+ help T lymphocytes recognise microbial antigens presetned to them by antigen presenting cells
they also stimulate effector cells: the CD8+ and T-cytotoxic lymphocytes and B cells to produce antibodies.
both CD8+ and T cytotoxic lymphocytes and the antibodies are specifically targeted to attack the same antigen recognised by the CD4+ cell.
Also the generation of memory cytotoxic T cells and B cells is also stimulated by the CD4+ cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

CD4+

A

vulnerable to infection by HIV
CD4 is a glycoprotein receptor found on the Th cells (T helper), dendritic cells, macrophages and monocytes of the central nervous system)
however the virus must bind to co-receptor e.g. CCR5 to gain entry to the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

origin of HIV

A

from a mutated simian virus (SIV) found in certain monkeys and chimps
present in humans in 1950s or even earlier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

earliest confirmed HIV

A

1959- from patient blood in congos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

slim disease

A

attributed to HIV lymphadenopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

HIV link

A

lin between herpes simplex virus (type II) and an increased infection with the virus later shown to be HIV
HSV induced-ulceration deprives the mucosa of its protective epithelia barrier increasing the risk of transmission of HIV
also HSV stimulates the proliferation of CD4+ which increased HIV viral synthesis by the infected CD4+ cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

link between homosexuality and HIV

A

reflects the reduced barrier to infection offered by the glandular surface epithelium in the rectum, which is only one cell think, compared to the stratified squamous epithelium lining of the vagina and ectocervix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

transmission of HIV

A 
sexually,
infected blood (from shared needles)
breast milk
NOT
saliva swear or tears
HIV does not normally cross the placenta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

when is the risk of transmission of HIV through placenta increased

A

increased risk in patients whose recently acquitted hiv
or have high blood viral levels
or if there is a intrauterine infection
or mother is malnourished
or if mother has: malaria, STD, UTI or respiratory e.g. TB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

how non developed viruses get into cells

A

taken up by receptor mediated endocytosis

or injected into the host cell by phages

47
Q

HIV getting into cells

A

hiv’s gp120 surface antigen binds to CD4 recpor on the T helper cells and some macrophages, and also needs to bind to co-receptor cell CCR5 (attached to a G protein within the cell) the purpose of CCR5 it to recognise chemokine and is central to several inflammatory responses
after binding it meld and fuses its envelope with the hosts phospholipid bilayer and uncoats its viral RNA which enters the cytosol

the viral protein and genome are released and activate the transcription of new viral particles

HIV (retrovirus) can ‘reverse transcribe’ its RNA into DNA which enters the host cell nucleus and is then replicated forming new viral particles which bud out of the cell

48
Q

after initial infection of HIV

A

it might be silent or produce flu like symptoms for 2 weeks, may be ineffective for several years
during which time lymph node enlargement may occur at sites

49
Q

action of HIV

A

gradually causes death of T cells
(by T cell’s own PRR) which assemble into an inflammasome, activating capsizes and causing death of cell host T cell

may take many 8 years before the count of circulating cD4 T cells in blood falls below critical level of 500/uL

50
Q

without CD4+ cells (t helper)

A

there is no generation of memory T and Bcells so no memory of past infection, so body relies on innate immune system

51
Q

which cells have CD4+

A

T helper cells, monocytes, dendritic cells, macrophages

52
Q

after the infection of HIV happens

A

a person has AIDS
characterised by either:
CD4 count under 200/uL
or development of AIDS defining illnesses e.g. oppotunitic infections, which take advantage of deficient immune response e.g pneumonia (p. jirovecii or cytomegalovirus (CMV), oesophageal candidiasis, small bowel cryptosporidiosis or atypical mycobacteriosis (Mycobactierm avid-intracellulare), or cryptococcal meningitis (cryptococcus neoformans).

53
Q

AIDs defining malignancies

A

intracerebral lymphoma and Kaposi;s sarcoma (both secondary to infection with HHV8)

54
Q

natural immunity to HIV/AIDs

A

those with delta (triangle)32 mutations in their CCR5 receptor genes
seen in around 16% of people in northern europe

this mutation prevents the HIV p120 protein antigen from binding to mutated CCR5 receptor on the host cell surface

55
Q

HIV can be useful

A

a modififed and non pathogenic form of HIV can be used for gene therapy of X linked Wiskott- Aldrich syndrome
(WAS gene)
bone marrow stem cells can be transfected with working genes using modified HIV

56
Q

symptoms of AIDS

A 
lip warts
shingles
PCP
thrush
Kaposi's sarcoma
57
Q

3 classes of anti-retroviral drugs preventing formation of HIV DNA

A

integrase inhibitors prevent HIV DNA integrating into host DNA

Nucleoside reverse transcriptase inhibitors (NRTIs)

Protease inhibitors prevent

new viruses being formed

on-nucleoside reverse transcriptase inhibitors (NNRTIs)

58
Q

CD$ receptors are essential for immune response

A

macrophages engulfs pathogen
presents antigens on surface
Class II MHC molecule helps CD4 bind to Th cell (activated by interleukin 1)
interleukin 2 and other cytokines activate Th cells, B cells and Tc (cytotoxic)

Tc : cell mediated immunity (attack on infected cells)
B cell: humoral immunity (secretion of antibodies by plasma cells)

59
Q

where is there greatest frequency of CCR5 delta 32 mutated allele

A

european populations

60
Q

active immunity

A

protecting produced by a person’s own immune system
takes days/weeks to develop is usually permananet
can be natural or acquired

61
Q

passive immunity

A

protection transferred from one human or animal to another, by the transfer of an antibody (igG)
immediate but short term protection (Weeks or months)
can be natural (transplacental) or acquired

62
Q

active immunisation

A

(the more similar the vaccine is to the natural disease the better the immune response to the vaccine)

1) live pathogens -attenuated (i.e. weakened virulence)
2) killed micro-organisms
3) microbial extracts
4) vaccine conjugates( A conjugate vaccine is created by covalently attaching a poor antigen to a strong antigen thereby eliciting a stronger immunological response to the poor antigen. Most commonly, the poor antigen is a polysaccharide that is attached to strong protein antigen).
5) toxoids (chemically modified (with formaldehyde) toxin from pathogen but is no longer toxic but still antigenic)

63
Q

why was eradicating small pos successful

A

no animal reservoir
subclinical cases rare
infectivity does not precede overt symptoms
one Variola serotype (the virus comes in one variety)
effective vaccine
lifelong immunity
major commitment by governments

64
Q

problems with developing vaccines

A

different viruses may cause similar disease

alternation to virus e.g. antigenic drift (accumulation of mutations) or antigenic shift (recombination)

immune system cannot detect viral antigens

HIV and inflenza virus are particularly difficult due to their rapidly changing properties

65
Q

primary and secondary immune response and Booster effect

A

primary response:
first encounter with an antigen
relatively slow for B cells to produce antibodies (initially IgM)

subsequent response is more rapid because of memory B cells

66
Q

live attenuated vaccines

A 
polio (oral: sabin)
measles
mumps 
rubella
TB
67
Q

inactivated vaccines

A 
polio (subctaneous: salk)
pertussis
typhoid
hep A
influenza
68
Q

toxoid vaccines

A

tetanus

diphtheria

69
Q

components of organisms (fragment) vaccines

A 
haemophilus influenzae type b (hib)
heb B (surface protein recombinant)
pneumococci
70
Q

important pathogens which don’t have vaccines

A 
rhinoviruses (colds)
HIV/AIDs *
cytomegalovirus
epstein barr virus
hep C
gonorrhoea
syphilis
leprosy
tachoma
malraia *
all parasitic and protozoal infections
71
Q

calor

A

heat

72
Q

rubor

A

redness

73
Q

tumor

A

swelling

74
Q

dolor

A

pain

75
Q

cyanosis

A

blue coloured deoxyhaemoglobin

76
Q

atherosclerosis

A

plaques form in arteries

77
Q

vascular occlusion

A

blocking of arteries

depends on:
type of tissue involved
how quickly the occlusion develops
whether there is collateral circulation

78
Q

thrombosis

A

blocking of arteries caused by blood clot

79
Q

embolism

A

fragments of clot break away and travel to elsewhere

80
Q

burst blood vessels

A

haemorrhage

81
Q

blood vessels bulging before bursting

A

aneursym

82
Q

infarct

A

localised areas of schematic tissue necrosis generally caused by an impaired bloody supply

83
Q

haemotoma

A

extravasuclar accumulation of clotted blood

84
Q

petechaie purpura, ecchymoses

A

small haemorrhages

85
Q

hyperaemia

A

an increased volume of intravascular blood in an affected tissue which may result from increased flow (active hyperaemia) or reduced drainage (passive hyperaemia =congestion)

86
Q

infarction

A

‘stuffed’

87
Q

collaterals

A

venous system has more collaterals than arterial

88
Q

where are arterial colaterals

A

gut, the circle of Willis and to some extent the heart

89
Q

arterial thrombosis

A

middle aged and elderly
circulatory problems due to atherosclerosis
smokers, diabetes

90
Q

venous thrombosis

A

at any age
generally immobile e.g. after operation
calf muscle pain
swelling of foot and ankle

91
Q

virchow’s triad

A

alteration to the consituents of blood
damage to the endothelial layer of blood vessels
changes in the normal flow of blood

92
Q

Alterations to blood constituents:

A

Blood becomes hypercoagulable
Increased cells, platelets and plasma proteins
Decreased fluid

93
Q

damage to endothelial layer of vessels

A

Exposes the highly thrombogenic sub epithelial tissue
Balance between release of thrombogenic and anti-thrombogenic stimuli is shifted
Occurs due to physical, chemical or inflammatory disturbances

94
Q

changes to flow

A 
Turbulence:
Alteration to the normal lamellar flow pattern
Can damage endothelium
More important for arterial thrombosis
Stasis:
Speed of flow is reduced
Results in changes of thrombogenic and anti-thrombogenic stimuli
More important in venous thrombosis
95
Q

role of thrombosis 3 phases

A

1) adhesion of platelets to vessel wall
2) activation of platelets leading to change in shape and secretion of granules
3) aggregation of platelets and amplification of processes

96
Q

adhesion

A

when endothelium is damages and collagen is exposed
gpIa binds to collagen
gpIb binds to von Wille brand’s factor (vWF)
gpIIb/ IIIa which binds to fibrinogen and vWF

97
Q

thrombosis need for calcium

A

required for coagulation pathway

98
Q

thrombosis need for ADP

A

induces platelet activation
which change shape and synthesise thromboxane (TxA2) a prostaglandin

prostacyclin produced by epithelial cells and thromboxane produced by platelets interact with endothelium and other platelets to influence clot formation in opposing ways

99
Q

most common cause of defective platelet function

A

is aspirin therapy
due to inhibition of cyclooxyrgenase resulting in impaired thromboxane synthesis

after a single dose of aspirin the defect lasts 7-10 days (the life of a platelet)

aspiriin also inhibits PGI2 prodution in endothelial cells and

100
Q

pulmonary embolism

A

from venous emboli that pass through the right side of the heart into the pulmonary artery

101
Q

systemic embolism

A

from arterial system to a variety of organs

102
Q

arteriosclerosis

A

disease of the media
leading to increased wall thickness
decreased elasticity
hypertension

103
Q

atherosclerosis

A 
disease of the intimate
damage to endothelium 
narrowing of vessel
obstruction
thrombosis
104
Q

fibrous cap content (of plaque)

A

smooth muscle cells, collagen, elastin and proteoglycans

105
Q

cellular layer (of plaque)

A

macrophages, t lymphocytes and smooth muscle cells

106
Q

necrotic core

A

lipid, cellular debris, cholesterol clefts, foam cells

107
Q

difference between arterial and venous thrombosis

A 
arterial:
risk from atheroma
due to turbulent blood flow damage to endothelium 
sudden onset
infarction arterial embolism 
entire plaque embolisms 
(plaque forms against blood flow..)
venous
risk from immobility
due to stasis and hyper coagulability 
slow onset
pulmonary embolism
fragments of plaque embolism
(plaque forms towards blood flow...)
108
Q

coronary heart disease

A

due to narrowing of coronary arteries
angina is caused by pain from this narrowing
complete blocakge= myocardial infarction (heart attack)

109
Q

stability of plaque

A

activated macrophages secrete matrix metalloproteinases MMP which degrade collagen and decrease the structural stability of the plaque
also secreted are cytokines and interferon which may initiate smooth muscle apoptosis and damage endothelial cells

110
Q

unstable plaque characteristics

A 
eccentric architectures
lipid rich
macrophage rich
inflammation
endothelial damage
111
Q

desmoplasia

A

gives tumour hard texture due to proliferation of fibroblasts which produce collagenous connective tissue

112
Q

carcinomas

A

epithelia

113
Q

sarcomas

A

connective tissue

114
Q

lymphomas

A

lymphoid tissue

PATHOBIOLOGY BMS106 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions