PubMed Health⌕ Search

Biomedical subjects

G Orecchia

Publications and source records attributed to G Orecchia.

At least 19 recordsLinked to original sources
PubMed1992

Vitiligo is associated with a significant increase in HLA-A30, Cw6 and DQw3 and a decrease in C4AQ0 in northern Italian patients.

HLA polymorphisms of class I (HLA-A, B, C) of class II (HLA-DR, DQ) and of class III (C4A, C4B, BF) were investigated in 93 Northern Italian patients affected with vitiligo and in 388 controls. Vitiligo patients had significant increases in HLA-A30 (corrected p, pc = 0.0144), Cw6 (pc = 0.0189), DQw3 (pc less than 0.0003) and a significant decrease in C4AQ0 (pc = 0.003). Nonfamilial vitiligo is marked by increases in HLA-A30 and DQw3. Extensive vitiligo is marked by increases in HLA-A30 and Cw6. These findings suggest that immunogenetic mechanisms may be responsible for vitiligo and that unique HLA phenotypes may influence the expression of vitiligo in this population.

Adolescent↗
PubMed1992

Photochemotherapy with topical khellin and sunlight in vitiligo.

In order to evaluate the efficacy of topical khellin the vitiligo macules of one side only were painted in 41 patients with a 2% solution of khellin in acetone and propylene glycol (90 and 10%, respectively) and exposed to sunlight for a period of 4 months with 3 weekly applications and with exposure times up to 90 min. The macules of the other side were treated in 36 of the 41 patients with acetone and propylene glycol only and sun-exposed with the same schedule, while in the remaining 5 patients they were neither treated with khellin or placebo nor sun-exposed. No significant difference was evidenced between the khellin and placebo-treated sides: no excellent result (repigmentation more than 75% of the affected area) was found, and good results (repigmentation more than 50%) were found in 24.9% of khellin- plus sunlight-treated macules and in 22.3% of placebo- plus sunlight-treated macules.

Administration, Topical↗
PubMed1992

Polymorphisms of HLA class III genes in allergic contact dermatitis.

HLA class III polymorphisms (BF, C4A, C4B) were studied in 55 patients of different age and sex suffering from allergic contact dermatitis, with sensitization to different substances. In the overall group of patients no significant correlation between the disease and HLA markers was found. BF F allele was present in 34% and BS S in 64% of patients suffering from allergic contact dermatitis to nickel only versus 16.45% (relative risk, RR = 2.61) and 80.76% (RR = 0.42), respectively, of the control population. The BF FB subtype frequency was 23.91% versus 7.57% in the control samples (RR = 3.88). We thus hypothesize that this polymorphic serum protein might be involved in the pathogenesis of allergic contact dermatitis to nickel.

Adolescent↗
PubMed1992

Expression, topography, and function of integrin receptors are severely altered in keratinocytes from involved and uninvolved psoriatic skin.

Psoriasis is a hyperproliferative cutaneous disease of unknown etiology and etiopathogenesis. Alteration of keratinocyte adhesiveness to basal lamina has been proposed as the initial disturbance leading to poorly controlled proliferation. Keratinocyte adhesion to basal lamina and lateral interactions among basal epidermal cells are mediated, besides other molecules, by integrin receptors that are segregated to discrete membrane domains. In this paper, the expression and function of integrins in psoriatic keratinocytes were examined, both in vivo and in vitro. We found that: (a) in psoriatic keratinocytes the integrin heterodimers alpha 2 beta 1, alpha 3 beta 1, and alpha 6 beta 4 have lost their polarized distribution on the plasma membrane; (b) the role of these integrins in mediating keratinocyte adhesion in vitro is altered; (c) psoriatic keratinocytes form focal contacts containing both beta 1 and beta 4 integrins. In normal adult keratinocytes the alpha 5 beta 1 fibronectin receptor is poorly expressed and diffusely distributed on the basal keratinocyte plasma membrane and is not organized in defined adhesive structures. In contrast, psoriatic keratinocytes show a clear fibronectin receptor staining in vivo, and organize alpha 5 beta 1 in typical focal contacts in vitro without any obvious increase of its expression and synthesis. These multiple alterations of integrins are also present in uninvolved keratinocytes from psoriatic patients, suggesting a key role for altered integrin-mediated adhesion in the pathogenesis of this disease.

Adult↗
PubMed1992

Autoimmunity in vitiligo: relationship with HLA, Gm and Km polymorphisms.

Eighty-six patients affected by vitiligo were investigated for Gm, and Km polymorphisms, HLA markers and the presence of organ and non organ-specific autoantibodies. Vitiligo patients had an increased frequency of autoantibodies (71%), in particular anti-parietal cells (26.6%), antithyroglobulin (24.4%) and antithyroid microsomal antibodies (43%). One patient was also affected by Hashimoto's thyroiditis, 4 by Graves' disease and two others by nontoxic, multinodular goiter. No correlation was found between chronologic age and sex and the presence of autoantibodies, while an increased frequency of organ-specific autoantibodies was found with longer duration of vitiligo. HLA-A3 and Gm (3; 23; 5, 10, 11, 13, 14) phenotype frequencies were significantly increased in patients without autoantibodies (P less than 0.05). Patients negative for these two phenotypes were significantly more prone to develop autoantibodies than those positive (P = 0.0032). C4AQO allele showed a significantly decreased frequency in the whole group of patients when compared to the controls (P less than 0.05).

Adolescent↗
PubMed1991

Age of onset in vitiligo: relationship with HLA supratypes.

HLA class I (A, B, C), class II (DR, DQ) histoglobulins and HLA class III (C4A, C4B and Bf) complement factors were analysed in 87 patients with vitiligo and in controls. Two HLA supratypes seem to mark different age of onset of vitiligo: HLA-BfS, C4A3, C4B1, DR5 (W11), DQW3 is characteristic of the pediatric form; while HLA-BfS, C4A3, C4B1, DR7, DQW2 marks the adult form of disease. The importance of defining HLA supratype, not single alleles, is discussed.

Adolescent↗
PubMed1991

Prevalence of atopy in vitiligo. A preliminary report.

59 patients suffering from vitiligo were investigated anamnestically and clinically with intradermal (prick tests) and laboratory tests (RAST and total IgE count) for the presence of atopy. Clinical manifestations (allergic rhinitis, asthma) and intense positive prick tests and RAST with an increase in total IgE count were found in 13 patients (22%). This frequency was significantly higher than that found in the normal population in our area (11.9%; p = 0.0212). These patients had a significantly higher incidence of vitiligo in their families (76.9 vs. 29.7% of the non-atopic; p less than 0.025), an earlier onset (14.1 vs. 24 years of the nonatopic) and a rapid worsening of the disease.

Adolescent↗
PubMed1990

Alopecia areata: more on topical sensitizers.

Our experience on treating alopecia areata with topical sensitizers (diphencyprone, squaric acid dibutylester) is reported: staging, prognosis, side effects, follow-up, and psychological attitude of the patients towards this therapy and wigs are the focused aspects. The possible mechanisms of action of these allergens are discussed, reporting the case of a female patient with concomitant appearance of hair regrowth and psoriatic plaques in the same area after SADBE therapy.

Administration, Topical↗
PubMed1990

Clonal structural chromosomal rearrangements in lymphocytes of four patients with Werner's syndrome.

Multiple numerical and structural chromosome abnormalities were found in cultured lymphocytes of four patients with Werner's syndrome. The proportion of metaphases with structural and/or numerical aberrations varied from 30 to 44% and several of them were clonal. These results confirm definitively that Werner's syndrome is a chromosome rearrangement syndrome and that these non-constitutional chromosome changes are not exclusive of cultured fibroblasts but present also in lymphocytes.

Adult↗
PubMed1979

Chronic bullous dermatosis of childhood.

A case of chronic bullous dermatosis of childhood in a 3-year-old boy is described. Immunoflourescence tests were negative and biopsy of the jejunal mucosa showed marked villous atrophy. The dermatosis was brought under control by a combination of diaminodiphenylsulphone and systemic steroids. The relationship with other bullous eruptions of childhood such as dermatitis herpetiformis and bullous pemphigoid is discussed.

Adrenal Cortex Hormones↗