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A Poiares-Baptista

Publications and source records attributed to A Poiares-Baptista.

13 recordsLinked to original sources
PubMed1992

Tiaprofenic acid-induced photohemolysis in vitro is inhibited by nimesulide.

The effect of nimesulide on red blood cell (RBC) lysis photosensitized by tiaprofenic acid was investigated. The tiaprofenic acid-induced photohemolysis rate was enhanced by exposure to oxygen but lysis was also observed under anaerobic conditions. Photohemolysis was decreased by reduced glutathione (GSH) and reduced even more by butylated hydroxyanisole (BHA); sodium azide, superoxide dismutase and mannitol did not show a significant effect. Nimesulide did not cause any RBC lysis and inhibited this action of tiaprofenic acid by 20-30%, depending on the concentration of nimesulide and the intensity of ultraviolet A light. The protective effect of GSH, but not of BHA, was increased by nimesulide. Our findings suggest that free radicals are generated in this in vitro model of phototoxicity and are involved in the photoaggression to the red blood cell membrane, this effect being partially inhibited by nimesulide.

Anaerobiosis↗
PubMed1990

Mechanism of action of doxepin in the treatment of chronic urticaria.

The present study examined 15 patients previously resistant to conventional antihistamines, in which doxepin at doses in the range of 50-75 mg/day was shown to be effective in treatment of chronic urticaria and without significant adverse side effects. However, some controversy remains about its mechanism of action in this particular disease. The aim of the present study was to examine the muscarinic, H1 and H2 blocking activity of doxepin. The following methods were used: a) gastric acid hypersecretion induced by histamine and carbachol in the pylorus-ligated rat preparation; b) contractile dose-response curves to histamine and carbachol in the guinea pig ileum; c) dimaprit-stimulated guinea pig atrium in vitro. pA2 values were determined for atropine, mepyramine, cimetidine and doxepin. As regards histamine, doxepin (50 mg/kg, po) increased gastric pH and decreased secretion volume, gastric acid concentration and total acid output; with carbachol, doxepin weakly antagonized those values. In the ileum, doxepin competitively antagonized carbachol (pA2 = 7.08) and histamine (pA2 = 9.72); pA2 values for atropine and mepyramine against carbachol and histamine were 9.11 and 8.82, respectively. In the atria, the dose-response curve to dimaprit was also competitively displaced by cimetidine (pA2 = 6.69) and doxepin (pA2 = 6.00). Doxepin displayed a very high affinity for H1 histamine receptor, being 8-fold more potent than mepyramine. Doxepin showed significant H2 blocking activity which was 5 times less potent than that of cimetidine. Doxepin competitively antagonized carbachol in the guinea pig ileum, and was 107 times less potent than atropine. The combined H1, H2 and muscarinic blocking activities of doxepin may contribute towards explaining its clinical efficacy in the treatment of chronic urticaria.

Adult↗
PubMed1988

Adrenergic urticaria.

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Diabetes Mellitus, Type 1↗
PubMed1988

Juvenile hyaline fibromatosis. A histologic and histochemical study.

Histochemical and routine light microscopic studies were performed in nodular skin lesions excised from one patient with juvenile hyaline fibromatosis. The lesions had different times of evolution. Recent lesions showed a high density of fibroblastlike cells embedded in an amorphous matrix of glycoproteins, hyaluronic acid, and small amounts of chondroitin sulfates A and C and of dermatan sulfate. The progressive enlargement of the lesions was due to an increase in the amount of intercellular matrix produced by the cells that progressively displayed a pattern of peripheral stratification. In the older lesions, the matrix was mainly composed by chondroitin sulfates A and C. We suggest that juvenile hyaline fibromatosis represents a disease of the connective tissue with progressive abnormal differentiation to chondroid tissue.

Alcian Blue↗
PubMed1987

Papular tuberculids post-BCG vaccination.

A 3-month-old child with a grossly symmetrical monomorphic papular acral-located skin eruption, a voluminous lymphadenopathy post-BCG vaccination, and hepatomegaly was seen. The diagnoses of Gianotti-Crosti's syndrome and generalized tuberculous infection have been discarded. The appearance of these lesions 48 hours after a tuberculin patch test, their tuberculoid structure, and the absence of any systemic involvement favored the diagnosis of papular tuberculids, a rarely reported complication of BCG vaccination.

BCG Vaccine↗
PubMed1987

Piroxicam-induced photosensitivity.

During the last 3 years, 9 patients with a photosensitive eruption related to piroxicam therapy were seen. In all but one, it occurred within 4 days of first exposure to the drug. 7 patients required systemic corticosteroids, and 2 hospitalization. Clinical, histological and provocation studies were not conclusive in classifying the eruption as photoallergic or phototoxic. Experimental studies including photohaemolysis, Bacillus subtilis culture and nuclear magnetic resonance showed: (i) in irradiated piroxicam solutions, there was more haemolysis; (ii) in irradiated Petri dishes, piroxicam solutions showed greater inhibition of growth of B. subtilis; (iii) Piroxicam's NMR spectrum is not modified after irradiation. The results provide evidence of piroxicam phototoxic potential.

Adult↗
PubMedDate not supplied

[Cutaneous infection with the cytomegalovirus virus in AIDS patients].

Cutaneous cytomegalovirus (CMV) infection has been observed in a variety of nonspecific skin lesions. Because of this fact, its diagnosis is rare and frequently accidental. The presence of the virus has also been observed in apparently normal skin, from both a clinical and histological point of view. In this context, skin biopsy and immunohistochemistry are often the first means of diagnosis of systemic CMV infection. In 180 skin biopsies carried out on HIV patients in the Infectious and Parasitic Diseases Unit, typical histopathological findings of CMV infection in a nonspecific skin lesion were observed in only one patient. Although the patient showed no extracutaneous manifestations at this time, she died soon after this diagnosis. Because of this fact, we review the literature and discuss the difficulties and implications of the diagnosis of cutaneous CMV infection in AIDS patients.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Verrucous herpes zoster in AIDS patients].

The authors describe a case of disseminated Herpes-Zoster (VZV) in an HIV 1 positive patient with AIDS. Hyperkeratotic characteristics, acyclovir resistance and sensitivity to foscarnet of cutaneous lesions are the most important features of this example. From the casuistics of the department, the authors describe two similar cases and review the medical literature with emphasis on etiopathogenic, diagnostic and therapeutic factors of lesions caused by DNA Virus in immunocompromised hosts.

AIDS-Related Opportunistic Infections↗