Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0849640 (skin damage)
 1,516 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In adults, intense staphylococcal skin colonization and hyperactivity of polymorphonuclear leukocyte (PMN) oxidative metabolism are characteristic features of atopic dermatitis. Precise data on childhood atopic dermatitis are lacking. In a prospective study we analysed the PMN chemiluminescence activity with special reference to staphylococcal stimuli in 19 children (mean age 6.2 years) with mild to moderate atopic dermatitis. Staphylococcus aureus was isolated from 17/19 (90%) of children with atopic dermatitis and 13/45 (29%) of healthy age-matched controls (p less than 0.001). The mean (SEM) chemiluminescence activity of unstimulated atopic dermatitis-PMN was 0.34 (0.009) (controls: 0.092 (0.003) x 10(6) cpm/10(6) PMN/min (p less than 0.02). Staphylococcal antigens (S. aureus, S. epidermidis, S. haemolyticus) induced a 1.9-3.1-fold higher peak chemiluminescence response in children with atopic dermatitis than in controls (p less than 0.05). The time interval until peak chemiluminescence activity was considerably shorter for all stimuli in atopic dermatitis. We conclude that PMN of children with atopic dermatitis are "primed", showing enhanced release of reactive oxygen metabolites even in the "resting" state, and are easily stimulated by staphylococcal antigens present on the skin of patients with atopic dermatitis from early childhood on. We speculate that PMN hyperreactivity may contribute to chronic skin damage in atopic dermatitis.
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PMID:Enhanced basal and stimulated PMN chemiluminescence activity in children with atopic dermatitis: stimulatory role of colonizing staphylococci? 139 70

Six fibroblast strains sensitive to long wavelength ultraviolet radiation (UVA) and one control strain were used to see if cooperation between the different cell strains could modify the abnormally high yield of single-strand DNA breaks (SSB) in the sensitive strains caused by UVA irradiation in complete Dulbecco's MEM. The sensitive strains were established from individuals showing proneness to different types of light-induced skin damage (actinic reticuloid, familial actinic keratoses with internal malignancies, and unusual frequency of basal cell carcinomata). When sensitive and normal cells were cocultivated, the UVA-induced SSB decreased in the sensitive cells and increased in the normal ones by amounts proportional to the ratio of the two types of cells in the mixtures. Furthermore the regression of SSB, in the sensitive cells, on the proportion of normal cells in the mixture extrapolated to normal levels of SSB when the proportion of normal cells increased to one. Cocultivation of different sensitive cells did not reduce the UVA-induced SSB to levels below those of the less sensitive cell strains. From these results we conclude that substances, present in limiting amounts, even in normal cells, can be transferred from cell to cell, presumably by metabolic cooperation, and modify the yield of SSB caused by UVA radiation. The abnormal yields of SSB in the sensitive cells appear to be entirely attributable to deficits in the substances responsible for the intercellular cooperation. We suggest that such substances are small molecular weight scavengers of active oxygen species.
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PMID:Cooperation between human cells sensitive to UVA radiations: a clue to the mechanism of cellular hypersensitivity associated with different clinical conditions. 205 75

When dehydration, infection, and mechanical trauma are prevented, procedures (such as cooling and/or oral antithromboxane) designed to diminish ischemia in experimental zone-of-stasis burns have been associated with no or only minor improvement in wound healing. To test the hypothesis that ongoing skin damage occurring postburn (PB) may in part be due to release of oxygen-derived free radicals during the 16-hour through 4-day PB period of reperfusion in such burns, beginning immediately and for a period of 5 days PB, equal numbers of guinea pigs received: allopurinol 150 mg/kg PO q 6 h vs. placebo, dimethylsulfoxide (DMSO) 75% applied topically q 12 h vs. placebo, or yeast-derived superoxide dismutase coupled with polyethylene glycol (PEG-SOD, Pharmacia) 10,000 U (Fridovich) given IV q 8 h producing a concentration of 16 U/cc of plasma 8 hr after injection vs. placebo. Gross and histologic examination of wounds by a 'blinded' investigator at 1 week and 3 weeks PB revealed no difference between treatment and control groups when rates of re-epithelialization and frequencies of hair-follicle retention were compared. Using the dosages, routes, and model described, treatment of a zone-of-stasis burn with PO allopurinol (a xanthine oxidase inhibitor), topical DMSO (a scavenger of the hydroxyl radical), or IV PEG-SOD (a scavenger of the superoxide radical) during the first 5 days PB was associated with no increase in the rate of re-epithelialization or frequency of hair follicle retention at 1 and 3 weeks PB when compared with controls.
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PMID:Oxygen-derived free radical inhibition in the healing of experimental zone-of-stasis burns. 302 94

The potential usefulness of i.v. injection of perfluorochemicals and breathing carbogen (95% O2 and 5% CO2) to improve the radiation-induced control of tumors was investigated. When C3H mice, bearing RIF-1 tumors in the legs, were given i.v. injections of Fluosol-DA (20%) at 12 ml/kg, and allowed to breathe carbogen for 1 h before and during a single dose of X-irradiation, the curability of tumors increased by a dose modification factor of 1.47 +/- 0.03 (SE). Such a treatment also increased the radiation-induced skin damage by a factor of 1.15 +/- 0.12, resulting in a therapeutic gain of 1.28 +/- 0.04. Measurement of intratumor pO2 by oxygen microelectrodes demonstrated small increases in pO2 when the animals breathed carbogen, and marked increases in pO2 when Fluosol-DA (20%) was injected into the animals and the animals breathed carbogen. It was concluded that i.v. injection of Fluosol-DA (20%) followed by carbogen breathing significantly improved the oxygen supply to hypoxic cells in the RIF-1 tumors and thus increased the control of tumors by radiation.
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PMID:Increase in pO2 and radiosensitivity of tumors by Fluosol-DA (20%) and carbogen. 309 9

A spray on, copolymer acrylic dressing (Op-Site) was used to limit the skin damage caused by a transcutaneous oxygen electrode and its adhesive ring. Two identical electrodes were applied to the abdominal skin of 10 preterm infants, one on untreated skin, the other after application of Op-Site. It was found that Op-Site prevented the epidermal damage (as measured by transepidermal water loss) that occurs when the adhesive ring is removed from untreated skin. It did not interfere with transcutaneous oxygen measurements; absolute values and response times were unchanged. Op-Site is therefore useful in preventing the skin trauma that occurs when transcutaneous oxygen monitoring is being performed in preterm infants below 30 weeks' gestation in the first week of life. Care must be taken, however, to prevent a build up of Op-Site--it should be applied as a single layer, allowed to dry, and removed after use.
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PMID:Reduction of skin damage from transcutaneous oxygen electrodes using a spray on dressing. 376 17

Data obtained from transcutaneously measured PO2 (tcPO2) were taken as an indication for a decreased oxygen supply to the skin in patients with chronic venous insufficiency III. Direct (invasive) measurements in LDS have not yet been performed. We therefore measured the intracutaneous PO2 (icPO2) in healthy skin and LDS (8 healthy volunteers and 18 patients with CVI III) with needle probes (250 microns tip diameter). The icPO2 values were compared with data of tcPO2 (37 degrees C and 44 degrees C electrode temperature). In healthy skin the mean icPO2 was about 50 mmHg and no steep PO2 gradients were found. In LDS (ulcer edge) mean PO2 values were lower than in healthy skin, however, no hypoxia or anoxia was observed. At the same site most tcPO2 (44 degrees C) values were between 0 and 5 mmHg. The mean icPO2 values from ulcer edges of different patients ranged from 6 mmHg to 42 mmHg (mean 22 mmHg). In LDS very different PO2 profiles were seen. There was no correlation between tcPO2 and icPO2 data. Our present results may suggest that skin damage in patients with CVI is not necessary associated with hypoxia.
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PMID:Differences between intracutaneous and transcutaneous skin oxygen tension in chronic venous insufficiency. 759 57

The major side effect of photodynamic therapy (PDT) using Photofrin is enhanced skin sensitivity for sunlight, which persists for 3-8 weeks after injection. Formation of singlet oxygen and radicals is believed to be involved in the basic mechanism of inducing skin damage. Reducing this side effect would make PDT more widely acceptable, particularly for palliative use. Hairless dorsal skin patches of mice, injected with 10 mg kg-1 photofrin intraperitoneally (i.p.) 24 h before illumination, were used to evaluate the effect of increasing light doses. The light was obtained from a halogen lamp and transmitted via a fiber optic to illuminate a field of 2.5 cm2. After establishing a dose-response relationship for single or fractionated light dose illumination of the skin, drugs known to scavenge radicals, quench singlet oxygen or interfere with histamine release were tested for their protective effect. N-acetyl-cysteine (NAC), a radical scavenger, administered i.p. (1000 and 2000 mg kg-1) 1 h before illumination produced a significant decrease in skin damage at light doses > 50 J cm-2 (protection factor of 1.3-1.8). When NAC was administered in a dose of 500 mg kg-1, no protection was observed. Fractionated illumination experiments in combination with multiple injections of NAC (1000 mg kg-1) also failed to show any protection. The addition of Ranitidine, a histamine blocking agent (25-100 mg kg-1), given prior to illumination, resulted in a limited protection at higher light doses. From this study we conclude that NAC could be of value in amelioration of the photosensitivity in patients treated with PDT.
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PMID:Partial protection of photodynamic-induced skin reactions in mice by N-acetylcysteine: a preclinical study. 802 87

Two young researchers were found lying beside 3 Dewar flasks for liquid nitrogen in a cold experimental room of a university. They were sent to a hospital but died 1.5 h after cardiopulmonary resuscitation. One of the cadavers had dark red discoloration of the skin on the left arm at autopsy. By the histological investigation of the discolored region karyopyknosis and vacuolation of the keratinocytes were noticeably observed in the epidermis. In addition, hyperemia and edematous changes were seen. Hemoglobin (Hb) was not immunodetected in the skin tissue except intravascular erythrocytes. Therefore, these histological findings of the discolored skin can indicate that the skin damage was produced by cold due to liquid nitrogen before death. The cause of death was asphyxia due to oxygen deficiency. There were few autopsy findings which showed the participation of liquid nitrogen in the accident. But, the histological findings of the discolored region demonstrate that liquid nitrogen was involved in this accident.
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PMID:On an accident by liquid nitrogen--histological changes of skin in cold. 859 37

Oxygen-centred free radicals play an important role in the pathogenesis of acute and chronic UV-induced skin damage as well as in skin aging. In this double-blind randomized study the efficacy of topically applied melatonin (N-acetyl-5-methoxytryptamine), a potent free radical scavenger, in the suppression of UV-induced erythema was assessed. A group of 20 healthy volunteers were irradiated with 0.099 J/cm2 UVB on four 5-cm2 areas on the lower back and topically treated with various concentrations of melatonin (0.05, 0.1, 0.5%) in a nanocolloid gel as carrier or with carrier alone. The UV-induced erythema was examined 8 and 24 h after irradiation by visual scoring and chromametry. A distinct dose response relationship was observed between the topical dose of melatonin and the degree of UV-induced erythema. Significant differences (P < 0.05) were found in redness (chromameter a-value and visual scoring) 8 h after irradiation between the areas treated with melatonin at 0.5% and those treated with melatonin at 0.05% or with the carrier. These results might open a new approach in the prevention and control of free radical-influenced skin diseases.
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PMID:Suppression of UV-induced erythema by topical treatment with melatonin (N-acetyl-5-methoxytryptamine). A dose response study. 887 46

Glutathione S-transferases (GSTs) play a primary role in cellular defense against electrophilic chemical species and radical oxygen species. Because free radical attack is one mechanism of UV irradiation-caused skin damage, we investigated whether genetic variation at the GST loci GST T1 and GST M1 influences individual UVB sensitivity. In a double-blind clinical trial, 50 healthy volunteers were evaluated for minimal erythema dose of UVB irradiation, MED (J/cm2), skin types were assigned, and internal standard-controlled polymerase chain reaction (PCR) was used to identify their GST T1 and GST M1 genotypes. The five homozygous carriers of the GST T1 deletion (GST T1*0/0) presented with the most intensive inflammatory reactions after irradiation; they were significantly overrepresented among the highly UVB-sensitive subgroups (p = 0.006). Lack of GST M1 (GST M1*0/0, n = 27) tended to be more frequent only in UVB-sensitive subjects, and the proportion of the active GST M1 allelic variants *A and *B was similar in all UVB sensitivity subgroups. Three subjects with deficiencies in GST T1 and GST M1 had the most intense inflammatory responses. No effect of gender or genetic variations at the MC1R gene locus was established. Thus, heritable GST T1 deficiency may be a genetic determinant of individual skin sensitivity toward UV irradiation.
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PMID:Deficiency of glutathione S-transferases T1 and M1 as heritable factors of increased cutaneous UV sensitivity. 900 40


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