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1.
Expert Opin Pharmacother ; 8(9): 1365-71, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17563270

RESUMO

Seborrhoeic dermatitis (SD) is a chronic, inflammatory skin disorder, affecting areas of the head and body where sebaceous glands are most prominent and active. The disorder commonly affects hair-bearing areas of the head, including the scalp. Involvement on the face is usually limited to the hairline, eyebrows, nasolabial folds and ears, and may occur either with or without scalp involvement. Areas of the trunk where SD may occur include the body folds and the presternal area. The aetiology of SD is unknown, although hormones and the Malassezia spp., formerly known as Pityrosporum (naturally occurring yeasts), are thought to be involved in the development of the condition. SD responds to the use of antifungal medications such as ketoconazole, suggesting that the inflammation could be linked to the Malassezia spp. The mechanisms behind the therapeutic effect of ketoconazole for the management of SD form the basis of this review. The broad spectrum activity of Ketoconazole was reported in the early 1980s. Due to its potent effect against Malassezia spp. the development of ketoconazole for the treatment of various skin infections, in which a link was proposed with Malassezia spp., was initiated. Later on, a number of ancillary properties were described for ketoconazole, comprising antibacterial, anti-inflammatory, sebostatic and antiproliferative effects. The incorporation of ketoconazole in an adapted vehicle further promoted its efficacy. Recently, a new anhydrous gel containing 2% ketoconazole (Xolegel) was launched, in which all of the above properties were optimised.


Assuntos
Antifúngicos/uso terapêutico , Dermatite Seborreica/tratamento farmacológico , Cetoconazol/uso terapêutico , Administração Tópica , Antifúngicos/administração & dosagem , Géis , Humanos , Cetoconazol/administração & dosagem
2.
Clin Rheumatol ; 26(5): 836-40, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-16871353

RESUMO

Two elderly female patients with fatal calciphylaxis, despite nearly normal renal functions, occurring during treatment for giant cell arteritis, are described. The possible mechanisms for this association are discussed.


Assuntos
Calciofilaxia/etiologia , Arterite de Células Gigantes/complicações , Idoso , Idoso de 80 Anos ou mais , Evolução Fatal , Feminino , Humanos
3.
Curr Drug Targets ; 6(8): 849-62, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16375669

RESUMO

Dermatomycoses are among the most widespread and common superficial and cutaneous fungal infections in humans. These typically nonfatal conditions are difficult to treat, especially infections of the nail. Dermatomycoses are caused by filamentous fungi such as Trichophyton, Microsporum or Epidermophyton species. These filamentous fungi have a high affinity for keratin, an important component of hair, skin and nails, which are the primary areas of infection by dermatophytes. The antifungal agents currently marketed for dermatomycoses are mainly inhibitors of ergosterol biosynthesis, except for griseofulvin, which interferes with the cytoplasmic and nuclear microtubular system. Three different types of inhibitors of the ergosterol biosynthetic pathway have been proven to be effective in clinic: the azoles (e.g. topical miconazole and topical/oral ketoconazole, itraconazole and fluconazole), the allylamines (e.g. terbinafine) and morpholines (amorolfine). Even today more effective antifungal azoles with less adverse effects and short-term therapy are deemed necessary to treat dermatophytosis. A promising novel triazole compound in this respect is R126638, which showed potent in vitro and in vivo activity.


Assuntos
Antifúngicos/uso terapêutico , Dermatomicoses/tratamento farmacológico , Dermatomicoses/fisiopatologia , Alilamina/farmacologia , Azóis/farmacologia , Dermatomicoses/microbiologia , Dermatomicoses/prevenção & controle , Ergosterol/antagonistas & inibidores , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Morfolinas/farmacologia
4.
Contact Dermatitis ; 53(4): 201-6, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16191015

RESUMO

The purpose of this retrospective study was to test whether the initial pattern of clinical presentation of shoe dermatitis could indicate the causative allergen(s) and to estimate the odds on foot dermatitis in patients with a positive patch test versus those with a negative patch-test result. Between 1990 and 2002, 8543 patients were patch tested with the standard series (and additional allergens, if appropriate). Of them, 1168 (14%) had been referred because of foot dermatitis and 474 of these patients (5.5% of the total group) presented a positive reaction to one or more substances related to shoes. We found that 6 standard allergens in the male group and 8 standard allergens in the female group were statistically significant for the shoe dermatitis group. The data showed a relationship between the distribution pattern of the foot lesions and most of the allergens. These results have clinical applications since the gender of the patients and the localization of the foot eruptions can, indeed, indicate what allergen is involved.


Assuntos
Alérgenos , Dermatoses do Pé/diagnóstico , Sapatos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Dermatoses do Pé/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Estudos Retrospectivos
5.
J Eur Acad Dermatol Venereol ; 19(3): 332-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15857460

RESUMO

BACKGROUND: Although numerous studies have evaluated risk factors associated with cutaneous malignant melanoma (CMM), no such study has been carried out in Belgium. OBJECTIVES: To identify individuals who are at high risk of developing malignant melanoma in Belgium, which could enhance the efficacy of screening interventions and avoid unnecessary skin inspections. STUDY DESIGN/SETTING/SUBJECTS: We prospectively included patients who were diagnosed with invasive malignant melanoma between 1998 and 2001 at the Department of Dermatology in a case-control study. Controls were selected from the outpatient dermatology clinic. Participants were interviewed and clinically examined by a dermatologist. We asked questions concerning most known risk factors associated with malignant melanoma such as phenotypical and skin characteristics, and environmental and lifestyle exposures. To adjust for confounding variables and to estimate odds ratios (ORs) and 95% confidence intervals (CIs), a multivariate model was used. RESULTS: Although sunburn in childhood and substantial occupational solar exposure were modestly, but significantly, associated with malignant melanoma risk, clinical examination yielded several stronger risk factors. In a multivariate model, which adjusted for age, gender and skin phototype, phenotypical characteristics such as skin, hair and eye colour were significantly associated with the development of malignant melanoma. In the multivariate model, people with three or more atypical naevi were at more than 10-fold risk of developing a malignant melanoma (> or = 3 atypical naevi; adjusted OR = 11.40, 95% CI = 4.79-17.53) compared to those without an atypical naevus. The presence of one or more palpable naevi on the upper extremities or having solar lentigines increased the odds of developing malignant melanoma at least twofold. CONCLUSIONS: In Belgium, risk factors associated with malignant melanoma appear to be in accordance with previous studies. To assess peoples' risk profile, clinical skin examination is likely to yield the most important sporadic malignant melanoma risk factors. Therefore, focusing screening campaigns on individuals with predefined findings on skin self-examination may increase its efficacy.


Assuntos
Melanoma/etiologia , Neoplasias Cutâneas/etiologia , Bélgica , Estudos de Casos e Controles , Cor de Olho , Feminino , Cor de Cabelo , Humanos , Masculino , Melanoma/diagnóstico , Pessoa de Meia-Idade , Análise Multivariada , Nevo/complicações , Fenótipo , Estudos Prospectivos , Fatores de Risco , Neoplasias Cutâneas/diagnóstico , Pigmentação da Pele , Queimadura Solar/complicações , Luz Solar/efeitos adversos
6.
Br J Dermatol ; 150(4): 693-700, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15099365

RESUMO

BACKGROUND: Discoid lupus erythematosus (DLE) and systemic lupus erythematosus (SLE) are chronic inflammatory diseases of unknown aetiology; the relationship of DLE with SLE has been a subject of debate for many years. OBJECTIVES; To find evidence for systemic immune activation in DLE by analysis of the immunophenotypic profiles of circulating lymphocytes, and to compare these changes with those in patients with SLE. METHODS: The immunophenotypic profile of peripheral blood lymphocyte subsets from 23 DLE patients without clinical or laboratory evidence of systemic disease, 25 SLE patients and 38 healthy donors was characterized by two-colour immunofluorescence flow cytometry analysis. None of the patients was receiving corticosteroid or immunosuppressive treatment. RESULTS: Patients with DLE had increased numbers of circulating HLA-DR+ CD3+ T cells and HLA-DR+ CD4+ T cells, indicating systemic T-cell activation, and an expansion of CD5+ CD19+ B cells. Decreased numbers of T-cell subsets expressing the differentiation markers CD11b and CD16/56, and of CD16/56+ natural killer cells were also found. In SLE, the changes were similar but more pronounced. In addition, a profound CD4+ T-cell lymphopenia and an increase of HLA-DR+ CD8+ T cells were found only in SLE. CONCLUSIONS: Our data provide evidence for systemic activation of the cellular immune system in patients with purely cutaneous DLE. Similarities in the lymphocyte immunophenotypic profiles in patients with DLE compared with SLE suggest that there are common immunopathological processes in these two conditions.


Assuntos
Lúpus Eritematoso Discoide/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos/sangue , Adolescente , Adulto , Idoso , Antígenos CD/imunologia , Antimaláricos/uso terapêutico , Subpopulações de Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Citometria de Fluxo/métodos , Antígenos HLA-DR/imunologia , Humanos , Lúpus Eritematoso Discoide/tratamento farmacológico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia
7.
J Eur Acad Dermatol Venereol ; 17(3): 340-3, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12702082

RESUMO

We describe two patients in whom chronic radiodermatitis with therapy-resistant ulceration of the right scapular region developed, following percutaneous coronary intervention with fluoroscopic imaging. Contrary to most reported cases in the literature, which involve numerous cardiac catheterization procedures, in both patients described here the total radiation dose was given during two successive procedures, involving difficult and prolonged coronary intervention with stent implantation. In both cases, local treatment of the ulcerative lesions was insufficient, necessitating excision of the radiodermatitis area and replacement with a skin graft, with good therapeutic result. The incidence of radiodermatitis after percutaneous coronary interventions is rising with the increasing number and complexity of these procedures. The main risk factor is a long duration of fluoroscopy using the same incidence. The skin lesions encompass a wide spectrum, ranging from erythema, telangiectasia, atrophy, hyperpigmentation and hypopigmentation to necrosis, chronic ulceration and squamous cell carcinoma. The lesions can appear from 15 days to 10 years after the procedure. To prevent radiation-induced injury, the radiation dose has to be limited and monitored. Also, careful inspection of the skin at the site of exposure is necessary and the radiographic beam has to be restricted to the smallest field size. A good clinical follow-up at regular intervals is important after long and complicated procedures.


Assuntos
Angiografia Coronária/efeitos adversos , Radiodermite/diagnóstico , Radiodermite/etiologia , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Cateterismo Cardíaco/efeitos adversos , Diagnóstico Diferencial , Feminino , Fluoroscopia/efeitos adversos , Humanos , Masculino , Radiodermite/patologia , Radiodermite/cirurgia , Escápula , Transplante de Pele , Stents , Retalhos Cirúrgicos
8.
J Med Virol ; 64(4): 543-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11468742

RESUMO

Immunocompromised patients may have severe forms of infections. Since there is an increasing number of patients maintained under immunosuppressive therapy, we will be confronted with increasing frequency with these infectious problems. Effective treatments will be of great value. The case is described of a renal transplant with a giant orf lesion, which continued growing instead of regressing spontaneously as is observed usually. The treatment options in such patients are limited. It was decided to treat the patient with the antiviral drug cidofovir (HPMPC, Vistide. Topical cidofovir treatment resulted in complete regression of the lesion. This case is discussed in the context of the known literature on orf (ecthyma contagiosum).


Assuntos
Antivirais/uso terapêutico , Citosina/uso terapêutico , Ectima Contagioso/tratamento farmacológico , Dermatoses da Mão/tratamento farmacológico , Hospedeiro Imunocomprometido , Vírus do Orf , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Administração Tópica , Adulto , Cidofovir , Citosina/análogos & derivados , Ectima Contagioso/patologia , Ectima Contagioso/virologia , Feminino , Dermatoses da Mão/patologia , Dermatoses da Mão/virologia , Humanos , Resultado do Tratamento
9.
Clin Infect Dis ; 33(5): 597-602, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11477525

RESUMO

Genital condylomata acuminata are nonmalignant human papillomavirus (HPV)-induced tumors in which HPV types 6 and 11 are most commonly found. Usual treatments for condylomata acuminata are nonspecific and are based on the destruction or removal of infected tissue. These procedures are often painful and are characterized by a high relapse rate. We report here what is to our knowledge the first double-blind, placebo-controlled study of the use of cidofovir, a nucleotide analogue, for the treatment of genital papillomavirus infections. Thirty patients were enrolled in the study; 19 received cidofovir, and 11 received placebo. The median number of warts and the median baseline wart area were comparable for both groups. Nine (47%) of 19 patients in the cidofovir group had a complete response (total healing), compared with 0 of the patients in the placebo group (P=.006). None of the patients in the cidofovir group experienced progression of the disease, compared with 5 (45%) of 11 patients in the placebo group. The side effects recorded for both groups were comparable.


Assuntos
Antivirais/uso terapêutico , Citosina/uso terapêutico , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Papillomaviridae/efeitos dos fármacos , Infecções por Papillomavirus/tratamento farmacológico , Infecções Tumorais por Vírus/tratamento farmacológico , Adulto , Cidofovir , Citosina/análogos & derivados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Fatores de Risco , Resultado do Tratamento
10.
Cancer Res ; 61(12): 4916-22, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11406571

RESUMO

Mutations in the ras gene are key events in the process of carcinogenesis; in particular, point mutations in codon 61 of exon 2 of the N-ras gene occur frequently in malignant melanoma (MM). We searched for point mutations in the N-ras gene in a large series of primary and metastatic MM from 81 different retrospectively selected patients using the very sensitive denaturing gradient gel electrophoresis technique, followed by sequencing. The classical codon 12 and codon 61 mutations were found in 21 and 17% of the cases, respectively. No codon 13 mutation was found. A novel mutation at codon 18 of exon 1, consisting of a substitution of alanine (GCA) by threonine (ACA), was found in 15% of the primary MMs but in none of the metastatic MMs. All of the other cases were free of mutations. Using microdissected cells from distinctive MM growth phases as source of DNA for mutation analysis, this particular N-ras exon 1 mutation at codon 18 was already present in the radial growth phase and preserved throughout the successive growth phases; it was also found in a dysplastic nevi in continuity with a MM, indicating a clonal relationship between both lesions. Our findings also illustrate the clonal relationship between the distinctive growth phases in MM and suggest the codon 18 mutation to occur early in MM development. The MM in patients with this mutation were significantly thinner than those without a codon 18 mutation (P = 0.0257). Statistical analysis, comparing the group of codon 18 patients with the group of patients with the classical mutations and without mutations, revealed a highly significant difference in overall outcome. The cumulative probability of developing metastasis was significantly lower for the group patients with a codon 18 mutation (P = 0.0130). We can thus conclude that this codon 18 mutation identifies a group of patients with better prognosis than patients with melanoma that harbor wild-type sequence or classical activating point mutations in codon 12 or 61. Preliminary nucleotide binding measurements could not detect a difference between wild-type Ras protein and the mutant Ras(A18T) protein. However, for a precise elucidation of the role of the N-Ras(A18T) mutant in melanoma, additional studies aimed to measure the affinity to guanine nucleotide exchange factors and GTPase-activating proteins are needed.


Assuntos
Genes ras/genética , Melanoma/genética , Mutação Puntual , Códon , DNA de Neoplasias/genética , Éxons , Feminino , Guanilil Imidodifosfato/metabolismo , Humanos , Masculino , Melanoma/patologia , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Proteínas ras/genética , Proteínas ras/metabolismo
11.
Virchows Arch ; 438(5): 485-91, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11407477

RESUMO

Endothelins (ETs) exert several functions in human melanocytes, including proliferation, dendrite formation, and melanin synthesis. Among the ET receptors, the non-selective endothelin-B (ETB) receptor is the major receptor in melanocytes and malignant melanoma (MM) cells. In spite of the important role of ETs and their receptors in the growth and differentiation of melanocytes, the distribution and expression levels of ETB receptors in tissue sections of benign and malignant pigment cell lesions is still unknown. We combined immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) to study ETB receptor expression in benign and malignant pigment cell lesions and in normal skin. Immunohistochemistry on paraffin-embedded tissue sections of 159 cases revealed a significant increase in intensity of ETB receptor expression from common nevi over dysplastic nevi and primary MM to metastatic MM. Quantitative PCR using realtime detection on 75 samples confirmed the immunohistochemical results. These data add the ETB receptor to the growing list of tumor progression markers in MM and suggest that ETs play a role in the progression of MM in the skin.


Assuntos
Melanócitos/metabolismo , Melanoma/metabolismo , Nevo Azul/metabolismo , Receptores de Endotelina/biossíntese , Neoplasias Cutâneas/metabolismo , Biomarcadores Tumorais/metabolismo , Primers do DNA/química , Sondas de DNA/química , Progressão da Doença , Humanos , Imuno-Histoquímica , Melanócitos/patologia , Melanoma/genética , Melanoma/secundário , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Nevo Azul/genética , Nevo Azul/patologia , RNA Mensageiro/metabolismo , RNA Neoplásico/análise , Receptor de Endotelina B , Receptores de Endotelina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
12.
Dermatology ; 202(2): 151-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11306845

RESUMO

A 76-year-old woman, with a history of thymoma, presented with a painful extensive stomatitis, painful paronychia, lichenoid papules on the hands and superficial erosions on the neck and the trunk. Histological examination showed lichenoid changes, acantholytic blister formation and apoptotic keratinocytes. Direct immunofluorescence was positive for IgG both in the epidermal intercellular spaces and along the basement membrane zone. Indirect immunofluorescence was similarly positive in a pemphigus vulgaris pattern. There was only a partial response to intravenous corticoids. These findings allowed the diagnosis of paraneoplastic pemphigus. The diagnostic characteristics, histopathology and the differential diagnosis of this disease are discussed.


Assuntos
Síndromes Paraneoplásicas/diagnóstico , Pênfigo/complicações , Timoma/complicações , Neoplasias do Timo/complicações , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Mucosa Bucal/patologia , Síndromes Paraneoplásicas/patologia , Pênfigo/diagnóstico , Pênfigo/patologia , Pele/patologia
13.
Skin Therapy Lett ; 6(5): 1-3, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11242137

RESUMO

Oral contraceptives (OCs) can reduce acne by lowering the production of adrenal and ovarian androgens, by inhibiting 5-alpha-reductase, which in turn, reduces the levels of dihydrotestosterone, and by stimulating sex hormone binding globulin (SHBG), thus reducing the levels of free testosterone. In newer OCs, such as Tricyclen and Diane-35, the progestin component is minimally androgenic and anti-androgenic respectively, thereby enhancing the favorable profile of these products in the treatment of hyperandrogenic disorders, including acne. The efficacy of these agents and their long-term safety profile supports their use in various grades of acne in females: * As adjunctive therapy to topical agents for women with mild non-scarring acne desiring oral contraception * As primary therapy for patients with moderate non-scarring acne in combination with topical therapy and systemic antibiotics * As one of two preferred methods of contraception in patients with scarring and severe inflammatory acne being treated with systemic isotretinoin.


Assuntos
Acne Vulgar/tratamento farmacológico , Anticoncepcionais Orais Hormonais/uso terapêutico , Acetato de Ciproterona/uso terapêutico , Combinação Etinil Estradiol e Norgestrel/uso terapêutico , Etinilestradiol/uso terapêutico , Inibidores de 5-alfa Redutase , Acne Vulgar/etiologia , Acne Vulgar/fisiopatologia , Androgênios/fisiologia , Combinação de Medicamentos , Humanos , Estados Unidos
14.
Eur J Dermatol ; 11(1): 29-34, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11174134

RESUMO

Fluticasone propionate is the first of a new generation of fluorinated corticosteroids that have been synthesized with a view to separating local activity from undesirable side effects. In recent years, contact allergy to the newer topical corticosteroids has received increasing attention. The results of patch testing with fluticasone propionate, even in patients with a known contact allergy to corticosteroids, argue for a low sensitization and cross-sensitization potential.


Assuntos
Androstadienos/efeitos adversos , Anti-Inflamatórios/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Administração Tópica , Adulto , Idoso , Reações Cruzadas , Feminino , Fluticasona , Glucocorticoides , Humanos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro
15.
J Invest Dermatol ; 117(6): 1483-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11886512

RESUMO

Mutations in the ras genes are key events in the process of carcinogenesis; in particular, point mutations in codon 61 of exon 2 of the N-ras gene occur frequently in cutaneous melanoma. To investigate whether these mutations occur in early or late tumor progression phases, we searched for point mutations in the N- and K-ras genes in 69 primary cutaneous melanoma, 35 metastases, and seven nevocellular nevi in association with cutaneous melanoma. Lesions were microdissected in order to procure pure tumor samples from the distinctive growth phases of the cutaneous melanoma; the very sensitive denaturing gradient gel electrophoresis technique was used to visualize the mutations, and was followed by sequencing. Point mutations in the N-ras gene but not in the K-ras gene were detected on denaturing gradient gel electrophoresis. Twenty-three primary (33%) and nine metastatic (26%) melanomas showed bandshifts for N-ras. In the majority of cases, mutations occurring in early growth phases (i.e., the "intraepidermal" radial growth phase), were preserved in later growth phases (i.e., the invasive radial growth phase, vertical growth phase, and metastatic phase), which proves the clonal relationship between the successive growth phases. In three cases, however, the mutations differed between the distinctive growth phases within the same cutaneous melanoma, due to the occurrence of an additional mutation (especially in codon 61) in a later tumor progression phase. Our approach also permitted us to analyze the mutational status of nevi, associated with cutaneous melanoma. Six out of seven associated nevi carried the same sequence (mutated or wild-type) as the primary cutaneous melanoma, whereas in one case the sequence for N-ras differed between the primary melanoma and the associated nevus. In conclusion, this approach allowed us to demonstrate the clonal relationship between subsequent growth phases of melanoma and associated nevi; our results suggest that N-ras exon 1 mutations preferentially occur during early stages of tumor progression and hence may be involved in melanoma initiation, whereas those in N-ras exon 2 are found preferentially during later stages and hence are more probably involved in metastatic spread of cutaneous melanoma.


Assuntos
Genes ras/genética , Melanoma/genética , Mutação Puntual , Neoplasias Cutâneas/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Melanoma/patologia , Nevo/genética , Nevo/patologia , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas
16.
Biochem Biophys Res Commun ; 279(1): 89-94, 2000 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-11112422

RESUMO

To improve our understanding of the cutaneous vitamin D system, we studied vitamin D receptor (VDR) gene regulation in cultured human keratinocytes. Because VDR and its ligand 1 alpha,25-dihydroxyvitamin D(3) have been implicated in epidermal growth control, we investigated VDR expression as related to cellular proliferation by using different cell cycle synchronization protocols. Keratinocytes, deprived of growth factors, were forced into quiescence and a concomitant loss of VDR expression was observed. Mitogenic stimulation of these G(0) cells however quickly upregulated VDR levels several hours ahead the G(1)-S transition point. Growth arrest at the G(1)-S border by mimosine treatment or at the metaphase by nocodazole also downregulated VDR levels but a restoration of VDR expression was again quickly achieved after reentering the cell cycle. These findings indicate that VDR expression in keratinocytes is restricted to actively cycling cells, but not limited to one particular phase of the cell cycle.


Assuntos
Ciclo Celular/genética , Queratinócitos/citologia , Receptores de Calcitriol/genética , Fator de Crescimento Epidérmico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mimosina/farmacologia , Nocodazol/farmacologia
17.
Melanoma Res ; 10(4): 371-80, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10985672

RESUMO

One to two per cent of primary cutaneous melanomas share clinical features with benign melanocytic and non-melanocytic skin lesions, and even at histology recognition of their malignant nature is problematic, mainly due to the lack of an intraepithelial component, their nodular aspect and the monotonous cell population throughout the lesion. These tumours were termed minimal deviation melanomas (MDMs) by Reed et al. and later naevoid melanomas by Schmoeckel et al. The name MDM suggests the concept of a more favourable outcome for these melanomas that do not (yet) show the typical features of fully evolved lesions able to metastasize, although naevoid melanomas seem to behave like 'common' melanomas. In a retrospective analysis of nine cases of MDM collected from our database and followed for a median duration of 112 months, we faced similar clinical and histological pitfalls and observed local recurrence following marginal resection. Wide excision, even of local recurrence, and therapeutic node dissection could nevertheless provide survival comparable at least to that predicted by mathematical models for patients who initially had optimal treatment.


Assuntos
Melanoma/patologia , Nevo de Células Epitelioides e Fusiformes/patologia , Nevo Pigmentado/patologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Melanoma/classificação , Melanoma/terapia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Nevo de Células Epitelioides e Fusiformes/classificação , Nevo de Células Epitelioides e Fusiformes/terapia , Nevo Pigmentado/classificação , Nevo Pigmentado/terapia , Prognóstico , Estudos Retrospectivos , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/terapia , Resultado do Tratamento
19.
Dermatology ; 200(2): 93-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10773693

RESUMO

This review addresses the current concepts about dandruff. The nature, origin and treatments of such skin conditions are scrutinized. The role of Malassezia spp. and other triggering factors is highlighted.


Assuntos
Dermatoses do Couro Cabeludo , Dermatite Seborreica/etiologia , Dermatite Seborreica/terapia , Humanos , Dermatoses do Couro Cabeludo/etiologia , Dermatoses do Couro Cabeludo/terapia
20.
Biochem Biophys Res Commun ; 268(1): 237-41, 2000 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-10652242

RESUMO

Apigenin, a flavonoid with chemopreventive properties, induces cellular growth arrest, with concomitant inhibition of intracellular signaling cascades and decreased proto-oncogene expression. We report that apigenin potently inhibited vitamin D receptor (VDR) mRNA and protein expression in human keratinocytes without changes in VDR mRNA half-life. Concurrently, downregulation of retinoid X receptor alpha, a dramatic loss of c-myc mRNA, and upregulation of p21(WAF1) took place. Furthermore, a nearly complete suppression of vitamin D responsiveness was observed as estimated by induction of 24-hydroxylase mRNA. The apigenin effect on VDR expression was shared by some other (quercetine and fisetine) but not all tested flavonoids. Interestingly, the apigenin-mediated VDR suppression was counteracted by the NFkappaB inhibitors sodium salicylate and caffeic acid phenethyl ester. The presented results propose suppression of nuclear receptor levels as a novel mechanism whereby flavonoids exert their pleiotropic effects. This study may also contribute to the understanding of the regulation of VDR expression in epidermal keratinocytes.


Assuntos
Flavonoides/farmacologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Vitamina D/farmacologia , Apigenina , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , Expressão Gênica/efeitos dos fármacos , Meia-Vida , Humanos , NF-kappa B/metabolismo , Proto-Oncogene Mas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Ácido Retinoico/genética , Receptores X de Retinoides , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética
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