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1.
Dermatology ; 207(1): 10-4, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12835541

RESUMO

BACKGROUND: Our surroundings are full of non-ionizing electromagnetic radiation (EMR) of different frequency and power. The non-ionizing EMRs emitted by television, computer and cellular phone (CF) sets have been increasing over the past few years. OBJECTIVE: The aim of our study was to assess the effects of non-ionizing EMRs (frequency 3 x 10(8) to 3 x 10(11) Hz), emitted by CFs, on cutaneous blood flow in healthy volunteers. METHODS: Thirty healthy volunteers (14 male and 16 female; age: 18-53 years) entered the study. Measurements of cutaneous blood flow were taken under standard conditions (temperature and humidity), using a laser Doppler He-Ne flowmeter that was applied to the ear skin by an optical fibre probe. Microflow values were recorded without CF contact with the skin (T0), with the CF turned off but in contact with the ear skin (T1), with CF contact and turned on (T2), with CF contact, turned on and receiving (T3). The microflow values were also recorded backwards: with CF contact and set turned on (T4), with CF contact and turned off (T5), without CF contact (T6). RESULTS: The mean value of basal microflow (T0), expressed as perfusion units (PU), was 51.26+/-11.93 PU. During the T1 phase, the microflow increase was 61.38%; in T2 it was 131.74%, in T3 157.67%, in T4 139.21% and in T5 122.90%; in T6, the microflow value was 57.58+/-10 PU (similar to the basal microflow). Statistically significant cutaneous microflow values (p<0.050) were observed comparing the T1 to T5 values with basal microflow (T0). Furthermore, in comparison with T1 values (CF turned off in contact with the ear skin), the T2, T3 and T4 data were statistically significant (T2 vs. T1: t=7.763 with p<0.050; T3 vs. T1: t=9.834 with p<0.050; T4 vs. T1: t=8.885 with p<0.050).


Assuntos
Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Microcirculação/efeitos da radiação , Neoplasias Cutâneas/etiologia , Pele/irrigação sanguínea , Adolescente , Adulto , Velocidade do Fluxo Sanguíneo , Estudos de Coortes , Orelha Externa , Feminino , Seguimentos , Humanos , Fluxometria por Laser-Doppler , Masculino , Pessoa de Meia-Idade , Probabilidade , Estudos Prospectivos , Fluxo Sanguíneo Regional , Medição de Risco
2.
Dermatology ; 203(4): 329-32, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11752823

RESUMO

BACKGROUND: Port-wine stains (PWSs) are characterized by an increased number of ectatic vessels. The treatment of choice is the use of some lasers such as pulsed dye lasers. However, some lesions are nonresponsive to laser treatment. Perhaps the vessels' depth and diameter and the thickness of the vessel wall are important factors influencing the effectiveness of the laser treatment. METHODS: To investigate whether epiluminescence microscopy (ELM) could be useful in determining the effectiveness of laser treatment of PWSs, we studied a group of patients with PWSs using both ELM and histological analysis. RESULTS: A correlation existed between a gray-whitish veil seen by ELM and the vessel depth judged by histology: when the veil was absent, the vessels were always found to be located only in the upper third of the dermis. CONCLUSION: We think that the gray-whitish veil is a distinctive dermoscopic feature that is able to differentiate between superficial vessels (absence of veil) and deeper vessels (presence of veil).


Assuntos
Microscopia/métodos , Mancha Vinho do Porto/patologia , Adolescente , Adulto , Diagnóstico Diferencial , Diagnóstico por Imagem/normas , Humanos , Pessoa de Meia-Idade
3.
Lasers Med Sci ; 16(3): 171-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11482814

RESUMO

Various types of lasers, such as the Q-switched ruby laser and the Alexandrite laser, cause selective damage to cutaneous pigmented cells and are currently used in the therapy of pigmented lesions. The aim of this study was to evaluate the effects of a diode laser at a wavelength of 810 nm on pigmented guinea-pig skin. The diode laser was supplied by OcuLight Iris Medical Instruments, Inc. and was used to deliver 0.15, 0.2, 0.3, 0.4, 0.5, 1 and 1.5 J/cm2 laser beams in micropulses of 100 micros. The study was carried out on albino and black-spotted guinea pigs (GP). After irradiation, punch biopsies were taken and analysed by light and electron microscopy. Albino animals developed just a few signs of cutaneous injury. This mostly consisted of spongiotic disarray, after the highest doses were administered (>1 J/cm2). In the black skin of spotted GPs alterations appeared at 0.15 J/cm2 and included melanosome damage and, at doses higher than 0.3 J/cm2, also melanocyte damage. These observations demonstrate that the diode laser at 810 nm selectively affects pigmented structures and that the cellular targets of diode laser radiation are the melanosomes. The diode laser specificity for melanin may provide a biological basis for the treatment of pigmented superficial cutaneous lesions.


Assuntos
Lasers/efeitos adversos , Melanócitos/efeitos da radiação , Pigmentação da Pele/efeitos da radiação , Pele/efeitos da radiação , Animais , Feminino , Cobaias , Microscopia Eletrônica , Pele/citologia , Pele/lesões , Pele/ultraestrutura
6.
Dermatology ; 197(2): 115-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9732157

RESUMO

BACKGROUND: Smoking is known to be a primary cause of chronic harmful effects on the vascular system. It also induces some acute effects on the coronary circulation and on the ophthalmic artery. OBJECTIVE: The aim of our study was to assess the effect of smoking a single cigarette on cutaneous blood flow in habitual smokers as well as in nonsmokers. METHODS: A laser Doppler flowmeter was used to perform measurements of cutaneous microcirculation. Flowmetric data were recorded (i) before smoking, (ii) inhaling from an unlighted cigarette, (iii) during cigarette smoking, (iv) 2 and (v) 5 min after smoking. RESULTS: We could show that smoking a single cigarette acts on the cutaneous microcirculation reducing blood flow in both groups of subjects (38.1% reduction in smokers and 28.1% reduction in nonsmokers; p <0.01). Interestingly, the recovery phase is faster in nonsmoker subjects than in smoker ones; in fact, the recovery is complete 2 and 5 min after cigarette smoking in nonsmokers and in smokers, respectively. CONCLUSION: Smoking a single cigarette decreases the cutaneous blood flow in habitual smoker as well as in nonsmoker subjects. Moreover, the slower recovery phase of smokers suggests that their microcirculation become inured to smoke.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Microcirculação/fisiopatologia , Pele/irrigação sanguínea , Fumar/fisiopatologia , Adulto , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Interpretação Estatística de Dados , Feminino , Estimulantes Ganglionares/efeitos adversos , Humanos , Exposição por Inalação/efeitos adversos , Masculino , Microcirculação/efeitos dos fármacos , Nicotina/efeitos adversos , Plantas Tóxicas , Pele/efeitos dos fármacos , Fumar/efeitos adversos , Fatores de Tempo , Nicotiana/efeitos adversos
7.
Br J Dermatol ; 138(4): 655-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9640374

RESUMO

Steroid sulphatase deficiency is a feature of recessive X-linked ichthyosis (RXLI) that causes the accumulation of sulphated steroids (SS) in various organs and cells. In a previous study, we detected elevated cholesterol sulphate (CS) and dehydroepiandrosterone sulphate (DHEAS) serum levels in a group of 15 RXLI patients selected in a narrow age range. In the present study both CS and DHEAS serum levels were qualitatively and quantitatively determined using gas-chromatographic analysis in a group of 33 RXLI patients ranging in age from 3 to 70 years. The levels of CS and DHEAS were significantly increased in all patients. Variations in SS were related both to patients' ages and clinical course of the disease; Serum SS levels start to increase in early infancy, peak at puberty, remain elevated in adults and decrease slightly in the elderly.


Assuntos
Ésteres do Colesterol/sangue , Sulfato de Desidroepiandrosterona/sangue , Ictiose Ligada ao Cromossomo X/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Cromatografia Gasosa , Humanos , Masculino , Pessoa de Meia-Idade
8.
Melanoma Res ; 8(1): 53-8, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9508377

RESUMO

It is now generally agreed that solar exposure is a major external factor in the causation of cutaneous melanoma in light skinned populations with red hair and a marked susceptibility to the acute effects of ultraviolet (UV) radiation. In the present study, we investigated the existence of a possible relationship between hair melanin composition and minimal erythema dose (MED), as an indicator of UV sensitivity, in a group of 15 healthy red-haired subjects aged 20-46 years. In spite of comparable skin and hair colour, marked variations were observed in the MED values as well as in the hair melanin composition. Phaeomelanin levels varied in the range 0.026-0.53% w/w and were generally comparable to or higher than eumelanin levels (0.042-0.17% w/w). No significant relationship was found between MED values and phaeomelanin, eumelanin or total melanin (eumelanin plus phaeomelanin) content. Notably, however, a gross positive correlation was found between the eumelanin/phaeomelanin ratio and the MED values. These results would suggest that a high UV sensitivity is associated with high phaeomelanin and low eumelanin levels, and point to the eumelanin/phaeomelanin ratio as a novel chemical parameter that could be used for predicting individuals at high risk for skin cancer and melanoma.


Assuntos
Melaninas , Melanoma/diagnóstico , Transtornos de Fotossensibilidade/diagnóstico , Neoplasias Cutâneas/diagnóstico , Raios Ultravioleta/efeitos adversos , Adulto , Biomarcadores , Feminino , Cabelo/química , Cor de Cabelo , Humanos , Masculino , Melaninas/análise , Melanoma/etiologia , Pessoa de Meia-Idade , Transtornos de Fotossensibilidade/etiologia , Projetos Piloto , Fatores de Risco , Pele/efeitos da radiação , Neoplasias Cutâneas/etiologia
9.
Dermatology ; 195(4): 317-20, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9529548

RESUMO

BACKGROUND: Individual UVB photosensitivity is usually investigated by determining the minimal erythemal dose (MED). Nevertheless, factors such as room light intensity and subjective experience of the observer can influence the erythema perception and, therefore, the MED assessment. OBJECTIVE: To evaluate the relationship between the clinical and the chromometric and microflowmetric analyses of the UVB-induced erythema in 2 healthy volunteers. METHODS: A bank of 6 fluorescent mercury vapor tubes (Philips TL 12/20 W) was utilized as a source of UVB light. Three skin areas (4 cm2), from the dorsal region of each subject, were irradiated with 3 different UVB doses corresponding to: (1) MED; (2) 0.7 MED, and (3) 1.3 MED. RESULTS: (1) both microflowmetric and chromometric parameters reached a maximum peak 10-12 h after irradiation and maintained high values also 30 h after irradiation; (2) both microflowmetric and chromometric values were directly related to the UVB doses; (3) in some cases the microflowmetric values started to increase when the chromatic changes were still undetectable. CONCLUSION: These preliminary data confirm that the visual determination of MED performed 24 h after irradiation is a correct procedure. Nevertheless, the microflowmetric may precede the chromatic changes suggesting that vasodilatation follows irradiation without a latent period.


Assuntos
Eritema/patologia , Fluxometria por Laser-Doppler , Espectrofotometria , Raios Ultravioleta/efeitos adversos , Adulto , Colorimetria , Eritema/etiologia , Estudos de Avaliação como Assunto , Humanos , Luz , Variações Dependentes do Observador , Doses de Radiação , Pele/irrigação sanguínea , Pele/patologia , Pele/efeitos da radiação , Pigmentação da Pele/efeitos da radiação , Fatores de Tempo , Vasodilatação/efeitos da radiação
10.
Photodermatol Photoimmunol Photomed ; 12(5): 200-3, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9112278

RESUMO

The in vitro sensitivity of human hematopoietic progenitors to PUVA, 8-MOP and UVA alone was investigated. 8-MOP alone at final concentrations of 150, 200, 600 and 1,000 ng/ml did not modify colony growth of circulating and bone marrow erythroid (BFU-E), myeloid (CFU-GM) and immature (CFU-GEMM) hematopoietic progenitors obtained from normal controls. The exposure of the same progenitors to increasing doses of UVA, up to 12 J/cm2, progressively decreased hematopoietic colony growth (with estimated 50% inhibition occurring at about 5 J/cm2). In vitro PUVA treatment (8-MOP 200 ng/ml followed by UVA 5 J/cm2) caused 90% growth inhibition of circulating and bone marrow hematopoietic progenitors. In addition, the treatment completely inhibited the formation of spontaneous erythroid colonies, obtained from 5 polycythemic patients, that are considered to be a marker of this neoplastic disease. PUVA cytotoxicity was assessed by the colorimetric MTT assay. The percentage of cell death after PUVA exposure was 29 +/- 10% for both peripheral and bone marrow mononuclear cells. Our findings indicate that 8-MOP alone is not toxic to hematopoietic progenitors whereas UVA treatment determines in vitro a dose-dependent inhibition of the clonogenic capacity of normal hematopoietic cells. PUVA treatment enhances this effect, causing a quite complete inhibition of hematopoietic progenitors colony formation from normal donors and spontaneous BFU-E colony formation from polycythemic patients.


Assuntos
Células-Tronco Hematopoéticas/fisiologia , Terapia PUVA , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Células Precursoras Eritroides/metabolismo , Eritropoetina/metabolismo , Hematopoese/efeitos dos fármacos , Hematopoese/efeitos da radiação , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Policitemia/fisiopatologia
11.
Photodermatol Photoimmunol Photomed ; 10(3): 102-5, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7947188

RESUMO

Ultraviolet B and psoralen plus UVA treatment induce antigenic and enzymatic changes in Langerhans cells (LC). The aim of this study was to investigate the visible (VIS) effect on mice LC surface markers. As visible source, a slide projector equipped with a 150-W tungsten lamp, emitting between 400 and 740 nm (maximum at 580 nm) was used. Mice (BALB/c and C3H) were divided into groups, each irradiated with visible single fixed doses (ranging from 10 to 1000 J/cm2). The mice backs were shaved before irradiation. Skin biopsies obtained immediately after irradiation were processed for immunofluorescence and electron microscopy. Immunofluorescent studies showed: 1) a complete depletion of LC membrane markers at a dose of 700 J/cm2; 2) no effect at visible doses ranging between 0 and 75 J/cm2; 3) a dose-dependent effect with doses between 100 and 700 J/cm2. Electron microscopy revealed no cellular damage of LC at the visible doses administered.


Assuntos
Membrana Celular/efeitos da radiação , Membrana Celular/ultraestrutura , Antígenos de Histocompatibilidade Classe II/efeitos da radiação , Antígenos de Histocompatibilidade Classe II/ultraestrutura , Células de Langerhans/efeitos da radiação , Células de Langerhans/ultraestrutura , Animais , Antígenos de Superfície/efeitos da radiação , Antígenos de Superfície/ultraestrutura , Relação Dose-Resposta à Radiação , Feminino , Imunofluorescência , Luz , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Microscopia Eletrônica , Doses de Radiação , Pele/citologia , Pele/efeitos da radiação
12.
J Dermatol Surg Oncol ; 20(2): 151-2, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8113510

RESUMO

OBJECTIVE: We propose a simple cryo-technique for the treatment of cutaneous soft fibromas. METHODS: This method, useful for fibromas larger than 4-5 mm in diameter, allows the freezing of the only soft fibroma without affecting the surrounding skin. RESULTS: The technique shows the following advantages: it is simple to perform, it avoids local anesthesia, and it can be used in pacemaker holders. CONCLUSION: The cosmetic results are very good.


Assuntos
Criocirurgia , Lipoma/cirurgia , Neoplasias Cutâneas/cirurgia , Criocirurgia/instrumentação , Criocirurgia/métodos , Humanos , Nitrogênio/administração & dosagem
13.
Artigo em Inglês | MEDLINE | ID: mdl-1390123

RESUMO

We investigated possible alterations induced by psoralen and ultraviolet A radiation (PUVA) on platelet function both in vitro and in vivo. In vitro, using conventional aggregometry and adenosine diphosphate (ADP), collagen, ristocetin and arachidonic acid as aggregating agents, platelet aggregation was determined on platelet-rich plasma (PRP) from normal subjects at basal conditions and following the addition of increasing concentrations of 8-methoxypsoralen (8-MOP) with and without exposure to ultraviolet A (UVA) light (5 J/cm2) and compared with UVA light exposure alone. At basal conditions and following exposure to UVA light alone, no changes in the normal platelet aggregation patterns were observed. Exposure to UVA light of PRP containing 8-MOP also demonstrated no abnormality in the platelet aggregation patterns at 8-MOP concentrations of 200 ng/ml. However, abnormal platelet aggregation as a response to ADP and collagen was observed at higher concentrations of 8-MOP, which was augmented upon exposure to UVA light. In vivo, platelet aggregometry was performed on PRP from 4 patients submitted to PUVA treatment at basal conditions, 2.5 h after oral ingestion of 8-MOP (0.6-0.8 mg/kg) and after 4 PUVA sessions. No patient showed modification of the platelet aggregation profile after either 8-MOP ingestion or PUVA treatment. Our study shows that 8-MOP at high concentrations in vitro impairs platelet aggregation by ADP and collagen augmented by UVA light exposure, but PUVA therapy causes no detectable abnormality in platelet function in vivo.


Assuntos
Metoxaleno/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos da radiação , Raios Ultravioleta , Difosfato de Adenosina/farmacologia , Humanos , Técnicas In Vitro , Terapia PUVA , Psoríase/sangue , Psoríase/tratamento farmacológico
14.
Acta Derm Venereol ; 72(1): 68-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1350153

RESUMO

We investigated the effect of treatment with peptide T on severe psoriasis in 5 patients. Within 2 months, peptide T led to complete remission of all lesions in 1 patient and to good improvement in 3 others. In 1 patient, no effect was observed.


Assuntos
Peptídeo T/uso terapêutico , Psoríase/tratamento farmacológico , Adulto , Relação CD4-CD8/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Índice de Gravidade de Doença
15.
Recenti Prog Med ; 82(12): 677-8, 1991 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-1815306

RESUMO

Literature reports that patients affected by X-linked ichthyosis (XLI) have a reduction of sweat glands and a decrease of sweat production. The sweat physiology of 28 patients, 14 with XLI, 7 with lamellar ichthyosis, 7 with dominant ichthyosis and 28 control subjects were examined with sweat test, performed by pilocarpine iontophoresis. In the same patients we have performed skin biopsy to evaluate quantitative and qualitative reduction of sweat glands.


Assuntos
Ictiose Ligada ao Cromossomo X/fisiopatologia , Sudorese , Adolescente , Adulto , Biópsia , Criança , Pré-Escolar , Feminino , Humanos , Eritrodermia Ictiosiforme Congênita/fisiopatologia , Ictiose Vulgar/fisiopatologia , Iontoforese , Masculino , Pilocarpina , Glândulas Sudoríparas/patologia
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