Vesiculation

Ephedrine, which is not a catecholamine, has weak oral activity as a bronchodilator and although it has some direct action at adrenergic receptors, its predominant mode of action is by displacing norepinephrine from storage vesicules. 2"Agonists which are in use or are under investigation are the result of quests for improved selectivity, retention of potency, oral activity, and longer duration of action. 

Primary skin irritation is the immediate result of the contact of a substance with skin. Symptoms appear only in the area of contact and generally correspond to local erythema and sometimes to edema and vesiculation but they commonly disappear in several hours. When there is a specific immunological response to the substance in contact with the skin, the substance is said to be a sensitizer. Subsequent responses to the contact of the skin with small amounts of this substance will probably cover large areas of the body and are not limited to erythema and edema but also to itching, suppuration, and a long persistence of the reaction. 

Croton oil is an extract of the seed of the plant Croton tiglium and has been commercially prepared as Croton resin since 1932. Its activity on the skin is related to free hydroxyl groups, which cause skin vesiculation even in low doses. 

Hauser, H. (1987). Spontaneous vesiculation of uncharged phospholipid dispersions consisting of lecithin and lysolecithin, Chem. 

Hauser, H., and Gaines, N. (1982). Spontaneous vesiculation of phospholipids a simple and quick method of forming unilamellar vesicles, Proc. Natl. Acad. Sci. USA. 79. 1683-1687. 

Much evidence supports a role for these proteins in exocytosis. For instance, injection of recombinant SNAP into the squid giant axon increases vesicular exocytosis. Also, membrane SNAP-25 and syntaxin are both targets for botulinum toxin while the vesicule protein, synaptobrevin, is a target for tetanus and botulinum toxins both these toxins are well known for disrupting transmitter release. 

Eczema An inflammatory skin disease with vesiculation, infiltration, watery discharge, and the development of scales and crusts... 

After administration of mercuric chloride to adult rat kidneys, several changes were found, for example, pars recta of the proximal tubular segment showing fragmentation and disruption of the plasma membrane, basophilic staining, vesiculation and disruption of endoplasmic reticulum and other cytoplasmic membranes, mitochondrial swelling, loss of mitochondrial dense granules and condensation of nuclear chromatin [223-225]. 

Morrissey et al. 1989 NTP 1985 Oishi 1990 Oishi and Hiraga 1980 Poon et al. 1995). However, some ultrastructural alterations in Ley dig cells, including vesiculation of the smooth endoplasmic reticulum, were noted in rats administered di-w-octylphthalate by gavage on 2 consecutive days (Jones et al. 1993). 

Dachary-Prigent, J., Freyssinet, J.M., Pasquet, J.M., Carron, J.C. and Nurden, A.T., 1993, Annexin V as a probe of aminophospholipid exposure and platelet membrane vesiculation a flow cytometry study showing a role for free sulfhydryl groups. Blood, 81 2554-2565... 

Dermal/Ocular Effects. Volunteers including the report s author were exposed topically to liquid from a remote water gauge this liquid contained 1,2-dibromoethane as well as other chemicals (Pfiesser 1938). Follow-up tests were formed with 1,2-dibromoethane. No dermal changes occurred when the liquid or 0.5 cc of 1,2-dibromoethane was applied to uncovered skin. A burning sensation, inflammation and vesiculation occurred when a cloth dressing saturated with the liquid was applied for 1-2 hours. Skin lesions resolved with treatment after 7-13 days. 

Symptoms of exposure Very irritating to eyes, nose and respiratory tract. An irritation concentration of 72.00 mg/m in air was reported by Ruth (1986). Exposure to 3,000 ppm for several min may result in serious blistering of skin, lung edema, and asphyxia leading to death (Patnaik, 1992). Ingestion may cause bronchospasm, difficulty in breathing, chest pain, and pulmonary edema. Contact with liquid ammonia or aqueous solutions may cause vesiculation or frostbite (IMIOSH, 1994). 

Symptoms of exposure Irritation of the respiratory system, eyes dermatitis vesiculation (Patnaik, 1992)... 

Coal Particle Unchanged- -with pore development -no softening, no vesiculation little change in vitrinite reflectance, -softening, some vesiculation but recognisable as coal. 

Cenosphere Mono- Isotropic or Anisotropic -spherical - subspherical in shape, single chamber, no secondary or tertiary vesiculation within the char wall, porosity 70%. 

Solid bertoid Predominantly Isotropic -solid, massive particle with no vesiculation, coal precursor material not recognisable, high reflectance solid, massive particle with no vesiculation. 

The interaction of a chemical (hapten) with epidermal proteins (carrier) can result in a hapten-carrier complex capable of activating skin-associated lymphoid tissue (sensitisation) and dissemination of antigen-specific T l)unphocytes (induction). Subsequent encoimter with the same or cross-reactive chemicals can result in the elicitation of a characteristic inflammatory skin reaction. The clinical condition is referred to as allergic contact dermatitis and is characterised by erythema, oedema, vesiculation and pruritus. Allergic contact sensitisation is, therefore, classed as a cell-mediated immunological response to chemicals that contact and penetrate the skin. 

Histological examination of the liver reveals extensive cen-trilobular necrosis with loss of characteristic architecture of the hepatic cords. TEM examination indicated that both hepatocytes and hepatic endothelial cells were destroyed. The only alterations noted prior to cell rupture were slight mitocondrial swelling and slight cell swelling. Damaged cells had extensive fragmentation and vesiculation of the membrane (34). 

Liquid anhydrous ammonia in contact with the eyes may cause serious injury to the cornea and deeper structures and sometimes blindness on the skin it causes first- and second-degree burns that are often severe and, if extensive, may be fatal. Vapor concentrations of 10,000 ppm are mildly irritating to the moist skin, whereas 3 0,000 ppm or greater causes a stinging sensation and may produce skin burns and vesiculation. With skin and mucous membrane contact, burns are of three types cryogenic (from the liquid ammonia), thermal (from the exothermic dissociation of ammonium hydroxide), and chemical (alkaline). ... 

Direct contact with the liquid may cause erythema and vesiculation prolonged or repeated contact has been associated with the development of a dry, scaly dermatitis or with secondary infections. Some skin absorption can occur with lengthy exposure to solvents containing benzene and may contribute more to toxicity than originally believed, but the dermal route is considered only a minor source of exposure for the general population. ... 

In humans, the liquid on the skin causes severe primary irritation and second-degree burns with vesiculation. Workers exposed daily at 5-10 ppm complained of irritation of the nose, throat, and eyes and, in some instances, headache and flushing of the skin of the face. Concentrations of 10-25 ppm are unpleasant and even intolerable to some subjects for exposure of more than a few minutes duration daily exposures of workers to less than 5 ppm (usually 1-2 ppm) resulted in no symptoms. ... 

Splashes of the liquid in the eye cause immediate and severe irritation dermatitis and vesiculation may result from skin contact with the vapor or the liquid. Although ingestion is unlikely to occur, it may cause coma and convulsions. ... 

High concentrations of vapor cause conjunctival irritation and blepharospasm. Liquid chloroform splashed in the eye causes immediate burning pain and conjunctival irritation the corneal epithelium may be injured, but regeneration is prompt, and the eye returns to normal in 1-3 days. Applied to the skin, chloroform causes burning pain, erythema, and vesiculation. ... 

Two drops of the liquid in the eyes of a rabbit caused slight conjunctival irritation but no corneal injury. The liquid in contact with the skin of a rabbit caused erythema, exfoliation, and vesiculation. ... 

Contact of solutions of ethylene oxide with the skin of human volunteers caused characteristic burns after a latent period of 1-5 hours, effects were edema and erythema and progression to vesiculation, with a tendency to coalescence into blebs, and desquamation. Complete healing without treatment usually occurred within 21 days with, in some cases, residual brown pigmentation. Application of the liquid to the skin caused frostbite three of the eight volunteers were said to have become sensitized to ethylene oxide solutions. The undiluted liquid or solutions may cause severe eye irritation or damage. 

Exposure to levels above 50 ppm for 1 hour can produce acute conjunctivitis with pain, lacrimation, and photophobia in severe form, this can progress to keratoconjunctivitis and vesiculation of the corneal epithelium. Prolonged exposure to 50 ppm also causes rhinitis, pharyngitis, bronchitis, and pneumonitis. 

The dust on dry skin may result in a delayed burning sensation, but, on moist skin, the sensation is almost immediate, producing erythema, which may progress to vesiculation. Prolonged or repeated exposure also may cause dermatitis. 

Contact with the eye by the gas or liquid resulted in transient irritation and conjunctivitis. Minor skin exposure to the liquid produced erythema and edema." Prolonged or repeated contact resulted in deeper burns with delayed vesiculation." It is doubtful that significant cutaneous absorption occurs. Although victims of skin exposure may show symptoms of neurotoxicity, inhalation is considered the likely cause."... 

Phenylhydrazine is a potent skin sensitizer that causes eczematous dermatitis with swelling and vesiculation in a high proportion of individuals who have had repeated skin contact. Based on results with other hydrazines, it is expected that phenylhydrazine could also be absorbed through the skin. ... 

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