The glycolic acid trichloroacetic acid peel.

BACKGROUND: Chemical peeling has become increasingly popular. Technique is more critical in medium depth peeling than with deeper peels because of variable penetration of the trichloroacetic acid. OBJECTIVE: This article describes a novel use of two caustic agents, glycolic acid and trichloroacetic acid, to effect a predictable approach to medium depth peeling. METHODS: Without other skin preparation, 70% glycolic acid was applied to the entire face and diluted with water after 2 minutes. Then, 35% trichloroacetic acid was applied over the same areas. Biopsies were done on selected patients after 24 hours and 30, 60, and 90 days. RESULTS: Both clinically and histologically the glycolic trichloroacetic acid peel resulted in medium depth injury. Improvement in pigmentary dyschromias and actinic damage was impressive. CONCLUSION: The GA-TCA peel provides a consistent approach to medium depth peeling to add to the armamentarium of the dermatologic surgeon.

Spice allergy evaluated by results of patch tests.

Allergic contact dermatitis caused by spices is well documented; however, commercial patch tests are unavailable. Between October, 1991, and August, 1992, a series of fifty-five patients with suspected contact dermatitis were tested at Ochsner Clinic for sensitivity to a group of spices at concentrations of 10 percent and 25 percent in petrolatum. Concordant patch test results (positive at concentrations of 10 percent and 25 percent) were most common with ginger (seven), nutmeg(five), and oregano (four); the remaining spices produced zero or one positive responses. Patients exhibiting positive reactions at only one concentration were more likely to do so at 25 percent: nutmeg (five), ginger and cayenne (four), curry, cumin, and cinnamon (three), turmeric, coriander, and sage (two), oregano (one), and basil and clove (zero). Solo responses at this level may represent a threshold for detecting true allergy or, as an alternative, a marginal irritant reaction. Those responding to only 10 percent concentrations generally did so weakly. Three patients were deemed to have relevant patch test responses to spices.

Loxoscelism.

Loxoscelism, or envenomation by the brown recluse spider, may result in necrotic lesions and systemic reactions, including hemolytic anemia. Histologically, it resembles a cutaneous Arthus reaction. The reaction mechanism involves interactions between complement, neutrophils, and the clotting system. It is best treated with analgesics, avoidance of early surgical debridement, and oral dapsone.

Location of brown recluse venom attachment sites on human erythrocytes by the firritin-labeled antibody technique.

Brown recluse spider (loxosceles reclusa) venom has been demonstrated by a ferritin-labeled antibody technique to attach to human erythrocyte cell membranes. The number of individual attachment sites per cell is proportional to the concentration of the venom used to sensitize the erythrocytes. Structural changes in the red cell membrane are associated with the venom attachment. These sites may be related to the red cell hemolysis which sometimes occurs in the human as a result of the spider bite.

Immunocytochemical localization of parathyroid hormone in bovine parathyroid glands and human parathyroid adenomas.

Light and electron microscopic localization of parathyroid hormone (PTH) in human and bovine parathyroid tissue has been achieved using an indirect peroxidase labeled antibody method. Granular deposition of the reaction product was found throughout the chief cell cytoplasm. There was no nuclear staining. At the ultrastructural level, parathyroid hormone localized by this method appeared to be largely confined to the secretory granules in the cytoplasm of cells. Mitochondria and nuclei were free of reaction product. Aggregated sacs of granular endoplasmic reticulum were minimally reactive, and Golgi apparatuses did not show reaction product.

Inhibition of human complement components by Loxosceles reclusa venom.

Venom from the brown recluse spider, Loxosceles reclusa, was capable of inactivation human C1-C7 in vitro. This inactivation occurred if venom was added to fresh adult human serum, human cord serum, or functionally pure specific human components. Optimal incubation conditions for the inactivation of each component were determined and were found generally to be in the range of 25 or 37 degrees C for 30-60 min. The alternative complement pathway did not appear to be involved, since C1, C4, and C2 were readily inactivated, and inactivation took place in sera depleted of factor B of the properdin system. Venom-induced inactivation appeared to require few, if any, serum cofactors, because, with the possible exception of C2, functionally pure components, as well as those in sera, were readily inactivated.

Identification and neutralization of biological activities associated with venom from the brown recluse spider, Loxosceles reclusa.

Venom from the brown recluse spider, Loxosceles reclusa, reacted with human erythrocytes to form venom-sensitized erythrocytes. These cells were agglutinated specifically by high dilutions of adsorbed rabbit antivenin or were lysed by normal blood group compatible human sera. The specific rabbit antivenin prevented venom from attaching to erythrocytes, from interacting with serum complement, and from producing dermonecrotic lesions in rabbits. Results of experiments involving heat inactivation and adsorption to erythrocytes provide circumstantial evidence to suggest that the three biological activities of venom could be associated with a single component or few components with similar properties. The component interacting with serum complement is immunologically distinct from a factor in cobra venom which possesses similar biological activities.