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1.
Photochem Photobiol ; 84(6): 1569-75, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18627519

RESUMO

In the in vitro evaluation of Sun Protection Factor (SPF), the photostability of the ultraviolet (UV) filters can have a major impact, especially for high-SPF formulations, but is generally not taken into consideration. In this study, we present a UV transmission spectrum measurement system utilizing a high-sensitivity UV photomultiplier tube with concomitant evaluation of photostability. We have developed an algorithm to estimate SPF in vitro by converting the amount of UV light transmission through the sunscreen layer into cumulative relative erythema effectiveness to obtain one minimal erythema dose. Thus, the algorithm uses the same endpoint as in vivo SPF methods, but with a photomultiplier tube as the detector instead of skin. The values obtained showed an excellent correlation with in vivo SPF values, even for high-SPF sunscreens exceeding SPF 50. This method should be suitable as an in vitro SPF testing method for regulatory purposes.


Assuntos
Algoritmos , Processos Fotoquímicos/efeitos da radiação , Pele/efeitos da radiação , Luz Solar , Pele/efeitos dos fármacos , Análise Espectral , Protetores Solares/farmacologia
2.
Acta Paediatr ; 97(12): 1686-90, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18671690

RESUMO

AIM: TT virus (TTV) is genetically variable and widespread without apparent pathogenicity; however, its epidemiological features in children were not fully understood, partly because blood sampling is often unacceptable for healthy children. We therefore used saliva specimens to investigate epidemiology of TTV infection in early childhood. METHODS: Saliva samples were collected from 83 1-month-old, 110 4-month-old and 49 42-month-old children. Peripheral blood mononuclear cells (PBMC) and saliva samples were obtained in pairs from 19 healthy adults aged 40 +/- 7 years. TTV DNA was detected and quantified by real-time PCR and classified into five genogroups (G1-G5) by a series of PCRs using genogroup-specific primer pairs. RESULTS: TTV DNA was detected in 6, 34 and 90% of children aged 1, 4 and 42 months, respectively, and in 84% of adults. Comparable levels of TTV DNA were detected in pairs of saliva and PBMC. TTV loads in saliva were much higher in children than in adults. G3 was the most common genogroup in all age groups. The second most prevalent was G4 at 1-4 months of age and G1 thereafter. CONCLUSION: The prevalence of TTV infection reached a plateau at or before 42 months; however, somehow different epidemiologic features were observed among genogroups.


Assuntos
Infecções por Vírus de DNA/virologia , Saliva/virologia , Torque teno virus/isolamento & purificação , Adulto , Fatores Etários , Pré-Escolar , Infecções por Vírus de DNA/sangue , Infecções por Vírus de DNA/epidemiologia , Infecções por Vírus de DNA/genética , Feminino , Variação Genética , Genótipo , Humanos , Lactente , Japão , Masculino , Pessoa de Meia-Idade , Prevalência , Torque teno virus/genética , Carga Viral
3.
Neonatology ; 92(4): 236-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17570943

RESUMO

Several studies have reported that postnatally acquired cytomegalovirus (CMV) infection can cause sepsis-like syndrome in premature infants. We here report a 622-gram birth weight male infant of 23 weeks' gestation who had sepsis-like syndrome and pneumonia. Substantial CMV loads were detected in peripheral blood cells, plasma, and urine when the patient was in crisis, but was decreased in parallel to clinical improvement without using ganciclovir. CMV DNA was not detected from his umbilical cord or Guthrie card, even by highly sensitive real-time PCR. Molecular profiles were indistinguishable between the CMV strain isolated from his urine and that from maternal breast milk, indicating postnatal acquisition of CMV through breast milk. Although he had transient hearing impairment, his neurodevelopmental outcome of 30 months of corrected age was normal. Further accumulation of clinical and virological data in postnatal CMV infection is necessary for evaluating the severity and selecting patients requiring antiviral therapy.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/transmissão , Recém-Nascido Prematuro , Leite Humano/virologia , Antivirais/uso terapêutico , Citomegalovirus/isolamento & purificação , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/tratamento farmacológico , Feminino , Ganciclovir/uso terapêutico , Humanos , Recém-Nascido , Masculino , Gravidez , Índice de Gravidade de Doença
4.
Pigment Cell Res ; 15(5): 348-56, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12213091

RESUMO

Long-term exposure to ultraviolet radiation B (UVB) induced pigmented spots in the dorsal skin of hairless mice of strain (HR-1 X HR/De)F1. To clarify the cellular mechanism for the development of these UVB-induced pigmented spots, we investigated changes in the proliferative activity of epidermal melanoblasts and melanocytes in the dorsal skin at various weeks after UVB irradiation. Epidermal cell suspensions from the dorsal skin of hairless mice were cultured in a serum-free medium supplemented with dibutyryl adenosine 3':5'-cyclic monophosphate (DBcAMP) and basic fibroblast growth factor (bFGF). The suspensions were prepared from dorsal skins of mice exposed to UVB for 4 weeks (the stage of hyperpigmentation). Suspensions were also prepared from mice at 3 (the stage of depigmentation), 8 (the stage of appearance of pigmented spots), 20 (the stage of development of small-sized pigmented spots) and 37 (the stage of development of medium-sized pigmented spots) weeks after the cessation of 8-week UVB exposure. At the stage of hyperpigmentation the proliferative activity of melanoblasts and melanocytes was suppressed. With the development of pigmented spots, the proliferative activity of undifferentiated melanoblasts gradually increased, and then followed the increase in the proliferative activity of differentiated melanocytes. These results suggest that the proliferative activity of epidermal melanoblasts and melanocytes in UVB-irradiated skin increases with the development of pigmented spots.


Assuntos
Diferenciação Celular/efeitos da radiação , Divisão Celular/efeitos da radiação , Epiderme/efeitos da radiação , Melanócitos/efeitos da radiação , Transtornos da Pigmentação/etiologia , Raios Ultravioleta/efeitos adversos , Animais , Contagem de Células , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Células Cultivadas , Meios de Cultura Livres de Soro , Di-Hidroxifenilalanina/metabolismo , Di-Hidroxifenilalanina/farmacologia , Células Epidérmicas , Epiderme/metabolismo , Feminino , Masculino , Melaninas/metabolismo , Melaninas/efeitos da radiação , Melanócitos/citologia , Melanócitos/metabolismo , Camundongos , Camundongos Pelados , Transtornos da Pigmentação/metabolismo , Transtornos da Pigmentação/fisiopatologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Células-Tronco/efeitos da radiação , Regulação para Cima/fisiologia , Regulação para Cima/efeitos da radiação
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