SKIN 6131 Flashcards

1
Q

protects the body against external insults in order to maintain
internal homeostasis

A

skin

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2
Q

Skin is _______ of our body mass

A

10%

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3
Q

Skin is the most accessible organ in the body (t or f)

A

T

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4
Q

It participates directly in ________, _________, ________, ________, and _________

A

thermal, electrolyte, hormonal,
metabolic, and immune regulation

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5
Q
  • Thick stratum
    corneum—good physical
    barrier
  • Common site of contact with
    chemicals
  • Occlusion with protective
    clothing

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Palm/soles

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6
Q
  • Moist, occluded areas
  • Chemical trapping
  • Enhanced percutaneous
    absorption

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Intertriginous areas

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7
Q

example of Intertriginous areas

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

axillae, groin, neck, finger webs, umbilicus, genitalia

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8
Q
  • Exposed frequently
  • Surface lipid interacts with
    hydrophobic substances
  • Chemicals frequently
    transferred rom hands

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Face

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9
Q
  • Poor barrier function—thin
    epidermis
  • Sensitive to irritants

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Eyelids

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10
Q
  • Chemical trapping
  • Occlusion

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Postauricular region

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11
Q
  • Chemical trapping
  • Hair follicles susceptible to
    metabolic damage

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Scalp

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12
Q
  • Increased sensitivity to
    irritants
  • Impaired barrier function

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Atopic dermatitis

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13
Q
  • Impaired barrier function

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Psoriasis

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14
Q
  • Predisposition to skin
    disorders
  • Variation in sensitivity to
    irritants
  • Susceptibility to contact
    sensitization

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Genetic Factors

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15
Q
  • Vasodilation—improved
    percutaneous absorption
  • Increased
    sweating—trapping

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Temperature

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16
Q
  • Increased
    sweating—trapping

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Humidity

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17
Q
  • Variation in relative humidity
  • Chapping and wind-related
    skin changes

(FACTORS INFLUENCING CUTANEOUS RESPONSES)

A

Season

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18
Q

Two major components of the skin that are separated by a basement membrane

A

epidermis and underlying dermis

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19
Q

Thickness of dermis

A

approximately 90% of the skin (has largely a supportive function)

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20
Q

span the epidermis and are embedded in the dermis

A

epidermal appendages

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21
Q

examples of epidermal appendages

A
  • Hair follicles
  • Sebaceous glands
  • Eccrine glands
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22
Q

Layer that separates the dermis from underlying tissues

A

adipocytes

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23
Q

Accumulation of fat has a cushioning action

A

adipocytes

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24
Q

Somehow regulates our body temperature

A

adipocytes

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25
Q

Supply the bulbs of the hair follicles and the secretory cells of the eccrine (sweat) glands.

A

Capillaries

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26
Q

The ducts from these glands carry a dilute salt solution (that is sweat) to the surface of the skin, where its evaporation provides cooling sensation.

A

capillaries

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27
Q

Stratified squamous epithelium consisting primarily of keratinocytes

A

Interfollicular epidermis

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28
Q

Interfollicular epidermis is a stratified squamous epithelium consisting primarily of __________

A

keratinocytes

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29
Q

stimulated by ultraviolet light in the epidermis to produce melanin granules which are extruded and taken up by the surrounding keratinocytes and become pigmented

A

melanocytes

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30
Q

Widely distributed in the dermis, with occasional concentrations beneath the basal lamina and in the
papillae of hair follicles

A

Melanocytes

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31
Q

Dendritic, antigen-presenting cells usually involved in the immune response of skin to foreign agents,
particularly to xenobiotics

A

Langerhans cells (LCs)

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32
Q

Keratinocytes of the ___________ make up the germinative compartment

A

basal layer

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33
Q
  • Cells become flattened and increase in volume nearly 40-fold.
  • Lipid granules fuse with the plasma membrane, replacing the aqueous environment in the intercellular space with their contents.
A

Granular Layer

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34
Q
  • Plasma membranes of these cells become permeable and cell organelles are degraded, while a
    protein envelope is synthesized immediately beneath the plasma membrane.
A

Granular layer

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35
Q

Begins as keratinocytes leaving the basal layer, producing the outermost layer of the skin, the stratum corneum.

A

Terminal Differentiation

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36
Q
  • Mature cells
  • No longer viable
  • ~80% keratin in content
  • They are gradually shed from the surface and replaced from beneath
A

Corneocytes

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37
Q

process typically takes 2 weeks or basal cells to reach the stratum corneum and another 2 weeks to
be shed from the surface

A

Terminal Differentiation

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38
Q

When a basal cell divides, one of the progeny detaches from the basal lamina and migrates outward. Usually moves towards the skin surface

A

Terminal differentiation

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39
Q

The primary barrier to percutaneous absorption

A

Stratum corneum

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40
Q

the stratum corneum is formed during the process of ___________

A

terminal differentiation

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41
Q

the stratum corneum has _________ properties which prevents water loss from underlying tissues by evaporation

A

Hydrophobic

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42
Q

The SC is ordinarily hydrated which contains around ____ water or the moisture residing in corneocyte protein

A

20%

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43
Q

The lipids, a major component being ________, have a high content of long-chain ceramides removal of which seriously compromises barrier function as measured by TEWL

A

sphingolipids

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44
Q

Two intrinsic factors which contributes to the absorption rate of a given compound

A
  • Hydrophobicity
  • Rate of Diffusion through this barrier
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45
Q
  • Affects its ability to partition into
    epidermal lipid, and its rate of diffusion through this barrier
  • Usually computed using the
    octanol/water partitioning ratio
A

Hydrophobicity

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46
Q

↑ Kow = ____________

A

hydrophobic

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47
Q

Partitioning of an agent into the skin is greatly affected by its solubility in or adhesion to the medium in which it is applied (including soil) (t or f)

A

T

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48
Q

hydrophobic compounds, once in the SC, may diffuse rapidly into less hydrophobic regions below (t or f)

A

F; very slowly

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49
Q

Hydrophobic substances with low MW permeate the skin better than those with high MW or those that are hydrophilic. (t or f)

A

T

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50
Q

A list in order of decreasing permeability under steady-state
conditions gives the following hierarchy

A

foot sole > palm > scrotum > forehead > abdomen

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51
Q

Absorption through the epidermal appendages is generally
neglected because the combined appendageal surface area is
a small fraction of the total available area for the absorption (t or f)

A

T

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52
Q

Advantages of transdermal drug delivery

A
  • Provides a steady infusion or extended periods (typically 1 to 7 days) thereby avoiding large variations in plasma concentration
  • Preventing exposure to the acidic pH of the stomach
  • Avoid biotransformation in the
    gastrointestinal tract or from first-pass removal by the liver
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53
Q

For risk assessment and pharmaceutical design, the
most useful subject or experimentation is ___________

(Measurement of Penetration)

A

human skin

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54
Q

human skin is always used for clinical trials (t or f)

(Measurement of Penetration)

A

T

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55
Q

Human skin can also be used for pre-clinical trials (t or f)

(Measurement of Penetration)

A

F

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56
Q

For in vitro work, _______________ can be employed in special diffusion chambers, though care is needed to preserve the viability of the living layer of epidermis.

(Measurement of Penetration)

A

excised split-thickness skin

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57
Q

A simpler setup commonly employed uses ____________ skin with the lower dermis removed.

(Measurement of Penetration)

A

cadaver

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58
Q

No life. Lacks biotransformation
capability but retains the barrier function of the SC

(Measurement of Penetration)

A

Cadaver skin

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59
Q

To simplify determination of penetration kinetics, __________ may be employed and the _____________ monitored to measure penetration.
Pig skin may be used

(Measurement of Penetration)

A

skin flaps; capillary blood
flow

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60
Q

The major sites of biotransformation or metabolism of the skin
is the _________ and __________ of the skin.

A

epidermis; pilosebaceous units

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61
Q

Enzymes participating in the biotransformation that are expressed in the skin

A
  • CYP450
  • epoxied hydrolase
  • UDP glucuronosyltransferase
  • Quinone reductase
  • Glutathione transferase
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62
Q

Other metabolic enzyme activities detected in human epidermal cells include:

A
  • Sulfatases
  • β-glucuronidase
  • N-acetyltransferases
  • Esterases
  • Reductases
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63
Q

The intercellular region of the stratum corneum has catabolic
activities…..

A
  • proteases
  • lipases
  • glycosidases
  • phosphatase
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64
Q
  • Common skin disorder
  • Accounts or over 90% of reported causes (of all occupational skin
    disease)
  • involve in inflammatory processes and can have indistinguishable clinical characteristics of erythema
    (redness), induration (thickening and firmness), scaling (flaking), and vesiculation (blistering) on areas directly contacting the chemical agent.
A

Contact dermatitis

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65
Q

two types of contact dermatitis

A
  • irritant
  • allergic
    both may co-exist
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66
Q
  • Arises from the direct contact of agents on the skin at a higher concentration or longer exposure
  • Certain chemicals at sufficient concentration produce an acute irritation, sometimes called a second-degree chemical burn.
A

Irritant dermatitis

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67
Q
  • It can be produced by strong acids, alkalis, and powerful oxidizing or reducing agents can substantially disrupt the cornified layer, producing cytotoxicity directly
A

Irritant dermatitis

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68
Q

Contact with a variety of plants can also have irritant effects resulting in the production of proinflammatory cytokines like

A

IL1a, IL1B, and TNFa from keratinocytes

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69
Q

the back is more sensitive than the forearm (t or f)

A

T

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70
Q

____________ are the most sensitive to irritants and exhibit a propensity to produce specific IgE antibodies to allergens and typically suffer from hay fever

A

Atopic individuals

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71
Q
  • Extremely corrosive and reactive chemicals may produce immediate coagulative necrosis that results in substantial tissue damage
A

Chemical burns

72
Q

Manifestations of chemical burns

A

Ulceration and Sloughing

73
Q

Chemical burns are sometimes referred to as ___________

A

Third degree burns

74
Q

____________ can act as a chemical reservoir resulting in either continued cutaneous damage or percutaneous
absorption and systemic injury after exposure

A

Necrotic tissue

75
Q
  • Potent skin corrosive
  • Contact with compressed
    gas can cause frostbite

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Ammonia

76
Q
  • Severe chemical burns
  • Extremely exothermic
    reaction—dissolving in water
    can cause heat burns

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Calcium Oxide (CaO)

77
Q
  • Liquid and concentrated
    vapors cause cell death and
    ulceration

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Chlorine

78
Q
  • Solutions and vapors may
    burn
  • Compressed gas can cause
    frostbite

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Ethylene oxide

79
Q

Severe burning with scar
formation

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Hydrogen chloride (HCl)

80
Q
  • Severe, painful, slowly healing
    burns from high concentration
  • Lower concentration causes
    delayed cutaneous injury
  • Systemic absorption can
    lead to electrolyte
    abnormalities and death
  • Calcium-containing topical
    medications and quaternary
    ammonium compounds are
    used to limit damage

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Hydrogen flouride (HF)

81
Q

High concentration causes
severe burns and blistering

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Hydrogen peroxide

82
Q

Liquid exposure produces
blistering, deep burns

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Methyl bromide

83
Q

Moist skin facilitates the
formation of nitric acid
causing severe yellow-colored burns

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Nitrogen oxides

84
Q

White phosphorus continues
to burn on skin in the presence of air

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Phosphorus

85
Q
  • Extremely corrosive even in
    low concentrations
  • Systemic absorption through
    burn sites may result in
    > Cardiac arrhythmias, Renal
    disease, and Death

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Phenol

86
Q

High concentration causes
deep burns, readily denatures
keratin

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Sodium hydroxide

87
Q
  • Severe burns with contact
  • Skin contact rarely may result
    in respiratory sensitization

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Toluene diisocyanate

88
Q

is a delayed (T-cell mediated) hypersensitive reaction

(SELECTED CHEMICALS CAUSING SKIN BURN)

A

Allergic contact dermatitis

89
Q

Unlike contact irritants where the response is generally
proportional to applied dose and time, contact allergens can
elicit action even at small doses (t or f)

A

T

90
Q

To induce sensitization, ______________ must penetrate the skin and become attached to carrier proteins

(ALLERGIC CONTACT DERMATITIS)

A

chemical haptens

91
Q

complete antigens are processed by ____________ and presented to ___________ in regional lymph nodes

A

Langerhans cells; type 1 -helper cells

92
Q

Subsequent exposure to the same antigen results in an amplified immune response characterized by ____________ and ____________

A

dermal infiltration; spongiosis

93
Q

Topical medications/hygiene
products

(COMMON CONTACT ALLERGENS)

A
  • Antibiotics
  • Therapeutics
  • Preservatives
  • Others
94
Q
  • Bacitracin
  • Neomycin
  • Polymyxin
  • Aminoglycosides
  • Sulfonamides

(COMMON CONTACT ALLERGENS)

A

Under antibiotics

95
Q
  • Benzocaine
  • Idoxuridine
  • α-Tocopherol (vitamin E)
  • Corticosteroids

(COMMON CONTACT ALLERGENS)

A

Under therapeutics

96
Q
  • Benzalkonium
    chloride
  • Formaldehyde
  • Formaldehyde releasers
  • Quaternium-15
  • Imidazolidinyl urea
  • Diazolidinyl urea
  • DMDM hydantoin
  • Methylchloroisothiaolinone

(COMMON CONTACT ALLERGENS)

A

Under Preservatives/personal care products

97
Q
  • Cinnamic aldehyde
  • Ethylenediamine
  • Lanolin
  • p-Phenylenediamine
  • Propylene glycol
  • Benzophenones
  • Fragrances
  • Thioglycolates

(COMMON CONTACT ALLERGENS)

A

Under Other topical medications and hygiene products

98
Q
  • Abietic acid
  • Balsam of Peru
  • Rosin (colophony)
  • Pentadecylcatechols
  • Sesquiterpene lactone
  • Tuliposide A

(COMMON CONTACT ALLERGENS)

A

Under Plants and trees

99
Q
  • Chloramine
  • Chlorhexidine
  • Chloroxylenol
  • Dichlorophene
  • Dodecylaminoethyl glycine HCl
  • Glutaraldehyde
  • Hexachlorophene
  • Thimerosal (Merthiolate)
  • Mercurials
  • Triphenylmethane dyes

(COMMON CONTACT ALLERGENS)

A

Under Antiseptics

100
Q
  • Diphenylguanidine
  • Hydroquinone
  • Mercaptobenzothiazole
  • p-Phenylenediamine
  • Resorcinol monobenzoate
  • Benzothiazole sulfenamides
  • Dithiocarbamates
  • Thiurams

(COMMON CONTACT ALLERGENS)

A

Under Rubber products

101
Q
  • Formaldehyde
  • Glutaraldehyde
  • Potassium dichromate

(COMMON CONTACT ALLERGENS)

A

Under Leather

102
Q
  • Abietic acid
  • Formaldehyde
  • Nigrosine
  • Rosin (colophony)
  • Triphenyl phosphate
  • Dyes

(COMMON CONTACT ALLERGENS)

A

Under Paper products

103
Q
  • Bisphenol A
  • Epichlorohydrin
  • Formaldehyde
  • Acrylic monomers
  • Cyanoacrylates
  • Epoxy resins
  • p-(t-Butyl)
    formaldehyde resin
  • Toluene sulfonamide resins
  • Urea-formaldehyde resins

(COMMON CONTACT ALLERGENS)

A

Under Glues and bonding agents

104
Q
  • Chromium
  • Cobalt
  • Mercury
  • Nickel

(COMMON CONTACT ALLERGENS)

A

Under Metals

105
Q

Chemical: Abietic acid

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Pine resin (colophony)

106
Q

Chemical: Balsam of Peru

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Pine resin, cinnamates,
benzoates

107
Q

Chemical: Bisphenol A

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Diethylstilbestrol, hydroquinone monobenzyl ether

108
Q

Chemical: Canaga oil

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Benzyl salicylate

109
Q

Chemical: Chlorocresol

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Chloroxylenol

110
Q

Chemical: Diazolidinyl urea

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Imidazolidinyl urea, ormaldehyde

111
Q

Chemical: Ethylenediamine di-HCl

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Aminophylline, piperazine

112
Q

Chemical: Formaldehyde

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Arylsulfonamide resin,
chloroallylhexaminium chloride

113
Q

Chemical: Hydroquinone

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Resorcinol

114
Q

Chemical: Methyl hydroxybenzoate

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Parabens, hydroquinone monobenzyl ether

115
Q

Chemical: p-Aminobenzoic acid

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: p-Aminosalicylic acid, sulfonamide

116
Q

Chemical: Phenylenediamine

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Parabens, p aminobenzoic acid

117
Q

Chemical: Propyl hydroxybenzoate

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Hydroquinone monobenzyl ether

118
Q

Chemical: Phenol

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Resorcinol, cresols, hydroquinone

119
Q

Chemical: Tetramethylthiuram disulfide

(COMMON CROSS-REACTING CHEMICALS)

A

Cross-reactor: Tetraethylthiuram mono- and disulfide

120
Q

is one in which invading substances that cannot be readily removed are consequently isolated.

A

Granulomatous reactions

121
Q
  • Silica
  • Talc (Seen in powders)
  • Paraffin or mineral oil
  • Beryllium
  • Gadolinium
  • Metallic mercury and zirconium compounds
  • tattoo dyes (containing cobalt, chromium, mercury, lead, iron, cadmium, and manganese compounds)
A

substances that may produce granuloma

122
Q

UV and visible spectra of solar radiation reaching the earth
extend from

A

290 to 700 nm

123
Q

wavelength of UV-C

A

< 290 nm

124
Q

wavelength of UVB

A

290-320 nm

125
Q

The protective skin pigment melanin, synthesized in melanocytes, absorbs a broad range of radiation from

A

UV-B

126
Q

Other chromophores in the skin include amino acids, primarily
_________ and to a lesser extent ________, and their breakdown products (e.g., urocanic acid), which absorb light in the UV-B range.

A

tryptophan; tyrosine

127
Q

Biologically, the most significant chromophore in the skin is
________ since damage from radiation can have lasting effects on
the genetic information in target cells.

A

DNA

128
Q

Most evident acute feature of UV radiation exposure is ___________.

A

erythema (redness or sunburn)

129
Q

Pigmentary changes
- Freckling and hypomelanotic areas
- Wrinkling
- Telangiectasias (fine superficial blood vessels)
- Actinic keratoses (precancerous lesions)
- Malignant skin lesions such as basal and squamous cell carcinomas and malignant melanomas

A

Chronic exposure to radiation

130
Q
  • From exogenous chemicals may be
    produced by systemic or topical administration or exposure.
A

Phototoxicity

131
Q

Phototoxic reactions may be produced either by systemic or topical exposures (t or f)

A

T

132
Q

the skin may appear red and blister within minutes to hours after ultraviolet light exposure, particularly
UV-A (320 to 400 nm)

(PHOTOTOXICITY)

A

Acute exposure

133
Q

responses may result in hyperpigmentation and thickening of the affected areas

(PHOTOTOXICITY)

A

Chronic reactions

134
Q

is the most commonly responsible for phototoxicity (wavelength)

A

UV-A (320 to 400 nm)

135
Q

may occasionally be involved (wavelength)

A

UV-B (290 to 320 nm)

136
Q
  • 8-Methoxypsoralen
  • 5-Methoxypsoralen
  • Trimethoxypsoralen

(SELECTED PHOTOTOXIC CHEMICALS)

A

Furocoumarins

137
Q
  • Anthracene
  • Fluoranthene
  • Acridine
  • Phenanthrene

(SELECTED PHOTOTOXIC CHEMICALS)

A

Polycyclic aromatic hydrocarbons

138
Q
  • Tetracyclines
  • Sulfonamides
  • Sulfonylureas
  • Nalidixic acid
  • Thiazides
  • Phenothiazines
  • Nonsteroidal anti-inflammatory drugs

(SELECTED PHOTOTOXIC CHEMICALS)

A

Drugs

139
Q
  • Disperse blue 35
  • Eosin
  • Acridine orange

(SELECTED PHOTOTOXIC CHEMICALS)

A

Dyes

140
Q
  • Hematoporphyrin

(SELECTED PHOTOTOXIC CHEMICALS)

A

Porphyrin derivatives

141
Q

is a type IV delayed hypersensitivity reaction, leading typically to eczema

A

Photoallergy

142
Q

Photoallergy requires prior sensitization to the chemical. (t or f)

A

T

143
Q

________ is necessary to convert a potential photosensitizing
chemical into a hapten that elicits an allergic response

A

UV light

144
Q

Pleomorphic disease with a multifactorial etiology

A

Acne

145
Q
  • The influence of sebum, hormones, bacteria, genetics, and
    environmental factors is well known.
  • Additionally papules, pustules, cysts, and scars may complicate the process.
A

Acne

146
Q
  • One of the most disfiguring forms of acne in humans
  • Caused by exposure to polyhalogenated aromatic
    hydrocarbons
A

Chloracne

147
Q

Chloracne is a common disease; however, its recalcitrant nature and
preventability make it an important occupational and environmental illness. (t or f)

A

F; Relatively rare

148
Q

Pigmentary disturbances can be classified into….

A

hyperpigmentation or hypopigmentation

149
Q
  • results from increased melanin production or deposition of endogenous or exogenous pigment in the upper dermis.
  • can arise from deposition of
    metals and drugs in dermal tissue
A

Hyperpigmentation

150
Q

is a loss of pigmentation from melanin loss, melanocyte damage, or vascular abnormalities.

A

Hypopigmentation

151
Q

Denote complete loss of melanin from the skin, imparting a porcelain-white appearance

A

Leukoderma (vitiligo) and depigmentation

152
Q

May develop for those allergens to which IgE antibodies have been elicited by previous or ongoing exposure, subsequent contact can lead to development of __________ (hives), typically in minutes, through an immediate type I hypersensitivity
reaction

A

urticaria

153
Q

are raised wheals that usually itch or sting and may appear reddish.

A

uticaria

154
Q

are major causes of acute urticaria

A

food allergies and pharmaceuticals

155
Q
  • Rare, life-threatening disease
  • Represents one of the most life-threatening dermatologic diseases that is caused by drugs and chemicals.
  • Involves detachment of ≥ 30% of the epidermal surface from the dermis, commonly accompanied by severe erosions of mucous membranes
A

Toxic Epidermal Necrosis (Ten)

156
Q

TEN commonly resembles an upper respiratory tract infection in the in the second month (fever, cough, sore throat, and malaise) (t or f)

A

F; first several days

157
Q

Mucous membrane involvement can result in ……

(TOXIC EPIDERMAL NECROSIS (TEN))

A

gastrointestinal hemorrhage, respiratory failure, ocular abnormalities, and genitourinary complications

158
Q

Nearly 200 drugs have been reported to cause this syndrome
with major contributors being:

A
  • anticonvulsants,
  • nonsteroidal anti-inflammatories
  • antibacterial
  • sulfonamides,
  • allopurinol,
  • nevirapine.
159
Q

Radiation from ________ wavelengths to _________ wavelengths has been shown to cause skin cancer

A

ionizing; ultraviolet

160
Q

Shortly after the discovery of radioactive elements at the turn
of the twentieth century, it was observed that X-rays could
cause:

A
  • severe burns
  • squamous cell carcinoma
  • basal cell carcinomas
161
Q

X-ray-induced nonmelanoma skin cancers (NMSC) continued
to be observed throughout the twentieth century, as X-rays
were used therapeutically until the mid-twentieth century or a
variety of skin diseases such as

A

acne, atopic dermatitis, psoriasis,
and tinea

162
Q

Although NMSC from X-rays are now uncommon, __________ or ________ still is seen as sequelae of radiodermatitis, which sometimes develops after X-ray treatment of internal malignancies.

A

dermal atrophy or sclerosis

163
Q

Most skin cancers in the US are now ___________

A

UV-induced

164
Q

Most common UV-induced skin cancers are:

A

NMSC and cutaneous malignant melanoma

165
Q

The _____ tumor suppressor gene has been targeted in nearly all squamous cell carcinomas

A

p53

166
Q

Substances rich in polycyclic aromatic hydrocarbons _______________ are skin carcinogens in humans and
animals.

A

coal tar, creosote, pitch, and soot

167
Q

Oxidative biotransformation of polycyclic aromatic compounds produces ___________ that can form DNA adducts

A

electrophilic epoxides

168
Q

_______ produced by rearrangement of the epoxides, can be oxidized further to ________, yielding active oxygen species, and they are also toxic electrophiles.

A

Phenols; quinones

169
Q

has been developed as an important target for carcinogenicity testing.

A

Mouse skin

170
Q

Advantage of the mouse skin carcinogenesis model

A

Ability to separate the neoplastic process into stages of initiation, promotion, and progression
depending on experimental design.

171
Q

Abundant element in the earth’s crust that is encountered
routinely in small doses in the air, water, and food.

A

arsenic

172
Q

High exposures from smelting operations and from well water
derived from rock strata with a high arsenic content are associated with:

A
  • arsenical keratoses (premalignant lesions),
  • black-foot disease (a circulatory disorder reflecting endothelial cell damage),
  • squamous cell carcinoma of the
    skin and several other organs (bladder, lung, and liver)
173
Q

(+ 3 oxidation state) avidly binds vicinal thiols and is
thought to inhibit DNA repair

A

Arsenite

174
Q

(+ 5 oxidation state) can replace phosphate in macromolecules such as DNA, but the resulting esters are
unstable.

A

Arsenate

175
Q

________ also alters DNA methylation, suppresses keratinocyte
differentiation markers, and enhances growth factor secretion
in the epidermis.

A

Arsenic

176
Q

_____________ has been considered the most likely detoxification
method, because the observed mono- and dimethyl arsenate
isolated in urine from exposed humans and animals are indeed
much less toxic.

A

Methylation