Search PubMed⌕ Search

Biomedical subjects

P Redondo

Publications and source records attributed to P Redondo.

At least 55 records · Page 3Linked to original sources
PubMed1996

Effects of low concentrations of cis- and trans-urocanic acid on cytokine elaboration by keratinocytes.

The urocanic acid cis isomer (cis-UCA) is a possible cutaneous photoreceptor for the immunomodulatory phenomena that follow ultraviolet B irradiation. Several experiments in animals show an inhibitory action of cis-UCA on cellular immunity. However, the action of cis-UCA on the synthesis of cytokines in keratinocytes remains unknown. Long-term cultures of normal human keratiocytes were prepared in a serum-free medium, and stimulated with 1 microgram/ml of phorbol 12-myristate 13-acetate (TPA) and UCA or UVB-UCA (10-100 micrograms/ml). Synthesis of the following cytokines was measured using ELISA and Northern blot techniques: TNF-alpha, IL-1 alpha, IL-1 beta, IL-6, IL-8 and TGF-beta 1. TPA increased TNF-alpha protein levels in culture supernatants. No changes in Il-1 alpha and IL-1 beta protein levels were detected in basal culture supernatant after TPA stimulus. TPA augmented RNA expression for TNF-alpha, IL-1 alpha, IL-1 beta and TGF-beta 1. UCA isomers did not induce cytokine changes in protein synthesis. Expression of IL-1 alpha and IL-1 beta genes was increased after exposure to 100 micrograms/ml UVB-UCA (70 micrograms/ml cis-UCA). A slight increase in TNF-alpha RNA expression was detected when the dose of UVB-UCA reached 100 micrograms/ml. No effects on cytokine synthesis were found after UCA stimulus. These results suggest that low doses of cis-UCA do not effect cytokine synthesis by keratinocytes.

Breast↗
PubMed1995

Skin cancer in heart transplant recipients.

BACKGROUND: The frequency of skin cancer in organ transplant recipients is high, up to 15%. OBJECTIVE: Our purpose was to determine the incidence of skin cancer in patients who underwent immunosuppression after heart transplantation and to determine the factors important in the appearance of skin cancer. METHODS: We studied the frequency of skin cancer in 92 of 111 patients after they underwent heart transplantation between January 1984 and December 1993. RESULTS: At least one cutaneous neoplasm (squamous cell carcinoma and/or basal cell carcinoma) developed in 14 patients (15.2%). The basal cell carcinoma to squamous cell carcinoma ratio was 1:1.5. The skin cancer appeared an average of 31.5 months after transplantation; the average was 36 months for squamous cell carcinoma and 25.3 months for basal cell carcinoma. Cumulative risk rose from 4.3% at 1 year up to 43.8% at 7 years after transplantation. The overall incidence of both types of skin cancer was 45.3 per 1000 posttransplant person-years, with an incidence of 25.8 for basal cell carcinoma and 29.1 for squamous cell carcinoma. Most skin cancers developed between 2 and 3 years after transplantation. All patients were exposed to a significant amount of ultraviolet radiation and had skin type II or III. We did not find a significant association between skin cancer and haplotype HLA-A3, HLA-A11, HLA-DR, and the number of mismatches for HLA-B. CONCLUSION: We found an increased progressive cumulative incidence of skin cancer in heart transplant recipients for two reasons: (1) immunosuppression and increased exposure to ultraviolet radiation in some patients, and (2) the skin type of certain patients. We emphasize the need for photoprotection in this group of patients and regular skin cancer screening examinations.

Adult↗
PubMed1995

Transfusion-associated acute graft-versus-host disease in a heart transplant recipient.

We report a heart transplant recipient who developed graft-versus-host disease (GVHD) following blood transfusion. We consider that heart transplant recipients should be included in the category of immunosuppressed patients who may develop this disease after being treated with blood products. We also consider that, at the present time, irradiation of blood products is the only useful method of avoiding development of GVHD in these patients.

Female↗
PubMed1995

Multiple pilosebaceous cysts.

We report two patients initially diagnosed as having steatocystoma multiplex (SM). Other cysts showed characteristics of eruptive vellus hair cyst (EVHC). More than 30 and 14 cysts, respectively, were removed with histological hybrid characteristics of SM and EVHC. This suggests that SM and EVCH are two closely related entities, which represent a naevoid malformation in the area where the sebaceous duct and hair follicle meet.

Adult↗
PubMed1995

Small intestinal sulphoxidation of albendazole.

1. The in vitro sulphoxidation of Albendazole (ABZ) by rat intestinal microsomes has been examined. The results revealed intestinal sulphoxidation of ABZ by intestinal microsomes in a NADPH-dependent enzymatic system. The kinetic constants for sulphoxidase activity were Vmax = 46 pmol/min/mg protein and Michaelis constant Km = 6.8 microM. 2. The possible effect of inducers (Arochlor 1254 and ABZ pretreatment) and inhibitors (erythromycin, methimazole, carbon monoxide and fenbendazole), was also studied. In rat pretreated with Arochlor 1254, Vmax was 52 pmol/min/mg protein, whereas oral administration of ABZ increased the intestinal sulphoxidation of the drug, Vmax being 103 pmol/min/mg protein. 3. Erythromycin did not change the enzymatic bioconversion of ABZ, but methimazole and carbon monoxide inhibited the enzyme activity by approximately 60 and 30% respectively. Fenbendazole (a structural analogue of ABZ) was a competitive inhibitor of the sulphoxidation process, characterized by a Ki or 69 microM. 4. These data demonstrate that the intestinal enzymes contributing to the initial sulphoxidation of ABZ may be similar to the hepatic enzymes involved in the biotransformation process by the P450 and FMO systems, a conclusion that needs to be further established.

Albendazole↗
PubMed1993

Graft-versus-host disease after liver transplantation.

We describe a case of graft-versus-host disease that developed in the recipient of an orthotopic liver transplant. A maculopapular eruption developed on postoperative day 25. After the diagnosis of graft-versus-host disease was made aggressive therapy was instituted, which resulted in a complete recovery.

Exanthema↗