Maria Letícia Cintra

Model for human skin reconstructed in vitro composed of associated dermis and epidermis

CONTEXT AND OBJECTIVE The technique of obtaining human skin with dermis and epidermis reconstructed from cells isolated from patients can enable autologous skin grafting on patients with few donor sites. It also enables in vitro trials on chemicals and drugs. The objective of this work was to demonstrate a method for obtaining human skin composed of associated dermis and epidermis, reconstructed in vitro. DESIGN AND SETTING Experimental laboratory study, in the Skin Cell Culture Laboratory of Faculdade de Ciências Médicas, Universidade Estadual de Campinas. METHODS Cells from human fibroblast cultures are injected into bovine collagen type I matrix and kept immersed in specific culturing medium for fibroblasts. This enables human dermis reconstruction in vitro. On this, by culturing human keratinocytes and melanocytes, differentiated epidermis is formed, leading to the creation of human skin composed of associated dermis and epidermis, reconstructed in vitro. RESULTS We showed that human skin composed of associated dermis and epidermis can be successfully reconstructed in vitro. It is histologically formed in the same way as human skin in vivo. Collagen tissue can be identified in the dermis, with cells and extracellular matrix organized in parallel to multilayer epidermis. CONCLUSIONS It is possible to obtain completely differentiated human skin composed of associated dermis and epidermis, reconstructed in vitro, from injection of human fibroblasts into bovine collagen type I matrix and culturing of human keratinocytes and melanocytes on this matrix.

Hypertrophic lupus erythematosus: a clinicopathological study of 14 cases.

Background:  Hypertrophic lupus erythematosus (HLE) is a distinct and rare subset of lupus erythematosus (LE). It is characterized by verrucous lesions, chronic in its course, and resistant to treatment. The purpose of this study was to identify clinical and histological characteristics of HLE.

Skin and oral lesions associated to imatinib mesylate therapy.

IntroductionImatinib mesylate is a tyrosine kinase inhibitor used to treat chronic myeloid leukemia (CML) throughout all the phases of the disease. In most cases, this drug is well tolerated; however, some cases experience side effects.Results and discussionSkin rashes and oral lesions are uncommon and appear to be dose-dependent. The authors report two cases of CML Ph+ in chronic phase patients who presented skin and oral lesions probably induced by imatinib therapy.

Lichen planus and lichenoid drug-induced eruption: a histological and immunohistochemical study

Introduction  Lichenoid drug eruption (LDE) shares similar features with lichen planus (LP), that could reflect the same pathogenesis. In LP, an autoimmune attack is accepted and cytotoxic T‐lymphocytes (CD8+) predominate, especially in late lesions. Apoptosis of keratinocytes may be mediated by CD8+ T and NK cells in two distinct ways: by the release of cytotoxic molecules such as perforin and granzyme B or by the Fas/FasL system. The immunological mechanisms involved in LDE are not yet fully established.

Subcutaneous and cerebral cysticercosis

Cysticercosis is a human infestation, which is considered the most common cause of seizures worldwide. The subcutaneous lesions can help in the diagnosis of neurocysticercosis. We describe a case of a 45-year-old patient with multiple cutaneous nodules first seen 2 years ago that were increasing in number, and normal neurologic and fundoscopic examination. Neurologic symptoms started 3 months before hospital admission as a mild headache and muscular weakness. The imaging examinations showed a massive central nervous system involvement. Physicians must be aware of the importance of subcutaneous nodule examination for the diagnosis of neurocysticercosis.

What do we (not) know about the human bartonelloses

The human bartonelloses are a group of diseases with a rapidly increasing clinical spectrum. Well known manifestations such as Carrions disease, trench fever, cat-scratch disease, and bacillary angiomatosis are examples of Bartonella sp. infection. Along with these diseases, recurrent bacteremia, endocarditis, septicemia, erythema nodosum, erythema multiforme, trombocytopenic purpura and other syndromes have been reported having been caused by bacteria of this genus. The infectious process and the pathogenesis of these microorganisms are poorly understood. The bartonelloses may have a benign and self-limited evolution in a host, or a potentially fatal one. These bacteria can provoke a granulomatous or an angioproliferative histopathologic response. As these diseases are not yet well defined, we have reviewed the four main human bartonelloses and have examined unclear points about these emergent diseases.

Remodeling of the human dermis after application of salicylate silanol

Recently, a controlled double-blind study in patients with photo-aged facial skin demonstrated the beneficial role of oral intake of silanol for skin, hair and nails. The aim of our pilot study was to investigate histologic alterations in human skin after injection of silanol. Seven healthy female caucasian volunteers with a moderate degree of photoaged skin received ten sessions of weekly injections of 0.1% salicylate silanol in the left ventral lateral forearm. The histologic features of punch biopsies of the treated area and the nontreated contralateral arm were compared and the collagen and elastic fibers quantified. Texture analysis was performed on digitalized microscopic images by analyzing the Sarkar fractal dimension or amplitudes (inertia values) after Fast Fourier transformation. The treated area revealed a statistically significant increase of the density of both collagen and elastic fibers. Texture analysis showed more compact and homogenously distributed collagen fibers after silicon injection. Our results suggest that the application of silicon may stimulate the production of collagen and elastic fibers leading to remodeling of the dermal fiber architecture, which may explain the improvement of the skin surface observed in clinical studies.

Cutaneous adverse reaction to 2-chlorodeoxyadenosine with histological flame figures in patients with chronic lymphocytic leukaemia

Introduction  2‐Chlorodeoxyadenosine (cladribine or 2‐CdA) is a purine analogue that has been used successfully in hairy cell leukaemia (HCL). Moreover, it has been increasingly used to treat chronic lymphoproliferative syndromes and paediatric acute myeloid leukaemia. Cutaneous side‐effects associated with this drug have seldom been described in cases of HCL.

Larva migrans: a case report and review

A case of massive Ancylostoma sp. larval infestation is presented in a patient who had received systemic corticosteroid therapy. What attracts attention in this case is the exuberance and rarity of clinical manifestation. Based on the pertinent literature, we discuss the mechanisms of parasital infection, the natural history of the disease and its treatment.

Diagnosis and Follow-Up of Keratoacanthoma-Like Lesions: Clinical-Histologic Study of 43 Cases

Background: Keratoacanthoma (KA) is easily confused with squamous cell carcinoma (SCC) on a clinical or a histopathologic basis. However, KA undergoes spontaneous regression, whereas SCC does not. Objective: Our objective was to study the histopathologic features associated with clinical regression in KA-like lesions to support the therapeutic option. Methods: Forty-three biopsies of KA-like lesions were taken at patient admission. One month later, surgical excision was performed in 18 growing lesions. Regressing lesions were left untreated. Classic histopathologic features and diagnosis were blindly recorded in both biopsies and surgical specimens. Results: On a clinical and a histologic basis, 32 lesions were assessed as KA and 11 as SCC. Features that indicated malignancy were observed in both groups, but the probability of SCC was 31 times higher in tumors with five or more of such features. Several of the histologically atypical lesions were found to regress. Conclusion: SCCs and KAs have more pathologic similarities than differences, especially in the proliferative phase. The combination of the most useful features did not allow the nosologic diagnosis in difficult cases but helped. Differential diagnosis was easier to determine after the 1-month follow up. Complete surgical excision should be indicated in nonregressing and growing lesions.