Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 186
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Med Mol Morphol ; 52(2): 99-105, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30276677

RESUMO

Basal cell carcinoma (BCC) is a malignant skin tumor originating from cells of the epidermal basal layer and adnexal epithelium, especially in sun-exposed areas. Unlike squamous cell carcinoma (SCC), BCC has a propensity to grow only locally possibly due to differences in the surrounding microenvironment including the basement membrane (BM) and stroma. To investigate the components constituting the BM and surrounding connective tissue in BCC and SCC, we analyzed the expression of BM proteins, nidogen 1 (NID1) and type IV collagen (COL4). We compared the immunohistochemical expressions of NID1 and COL4 among tumor specimens from BCC, SCC and its precancerous condition, actinic keratosis (AK), (n = 5 each condition). The expressions of NID1 and COL4 were both decreased around the tumor nest of SCC. In contrast, the expressions of both NID1 and COL4 around the nest of BCC were much higher than in the peri-lesional normal skin not only at the BM, but also in the surrounding stromal tissue. Our findings imply that the surrounding stromal cells of BCC, but not SCC or AK, excessively produce NID1 and COL4, which may be involved in preventing BCC cells from destroying the BM and invading the dermis.


Assuntos
Carcinoma Basocelular/metabolismo , Carcinoma de Células Escamosas/metabolismo , Ceratose Actínica/metabolismo , Glicoproteínas de Membrana/biossíntese , Neoplasias Cutâneas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Membrana Basal/metabolismo , Colágeno Tipo IV/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
2.
Br J Dermatol ; 177(1): 253-257, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27603812

RESUMO

A certain relationship between XPA gene mutations and the severity of symptoms has been observed in patients with xeroderma pigmentosum group A (XP-A). Patients with mutations within the DNA-binding domain usually exhibit severe symptoms, whereas splicing mutations in the same domain sometimes cause very mild symptoms. This inconsistency can be explained by a small amount of functional XPA protein produced from normally spliced transcripts. We herein report the case of an adult Japanese patient with XP-A with unusually mild symptoms. We identified a homozygous c.529G>A mutation in exon 4 of the XPA gene, which resulted in aberrant splicing with a 29-bp deletion in exon 4 causing a frameshift. Intact mRNA was observable, but a Western blot analysis failed to detect any normal XPA protein. We therefore evaluated the DNA repair capacity in normal cells in which the XPA expression was artificially diminished. The repair capacity was still present in cells with trace levels of the XPA protein. The repair capacity of the cells derived from our patient with mild symptoms was poor by comparison, but still significant compared with that of the cells derived from a patient with XP-A with severe symptoms. These results provide strong evidence that a trace level of XPA protein can still exert a relatively strong repair capacity, resulting in only a mild phenotype.


Assuntos
Mutação/genética , Splicing de RNA/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , Xeroderma Pigmentoso/genética , Feminino , Homozigoto , Humanos , Pessoa de Meia-Idade
3.
Clin Exp Dermatol ; 42(5): 523-526, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28543586

RESUMO

Phototherapy is a useful noninvasive therapy, but it can induce cutaneous malignant tumours, including squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). We report on a 79-year-old man who had long-standing mycosis fungoides for 40 years, which had been treated with psoralen ultraviolet A therapy for 37 years at a dose of approximately 5000 J/cm2 . Approximately 6 years before presentation, numerous types of cutaneous malignancies, including actinic keratosis, BCC and SCC, had begun to develop all over the patient's body. We hypothesized that he was experiencing a pathogenesis similar to patients with xeroderma pigmentosum (XP), and we therefore assessed his DNA repair capacity. Based on these investigations, the patient was eventually diagnosed as non-XP, even though we detected that his DNA repair capacity was slightly lower than that of normal controls, which may have led to the skin cancers. We speculate that multiple skin malignancies can be induced by long-term phototherapy in patients with slightly impaired DNA repair capacity.


Assuntos
Distúrbios no Reparo do DNA/diagnóstico , Micose Fungoide/radioterapia , Neoplasias Induzidas por Radiação , Neoplasias Cutâneas/patologia , Terapia Ultravioleta/efeitos adversos , Idoso , Carcinoma Basocelular/etiologia , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/etiologia , Distúrbios no Reparo do DNA/complicações , Humanos , Masculino , Melanoma/etiologia , Melanoma/patologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/radioterapia
4.
Skin Res Technol ; 23(1): 97-103, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27500370

RESUMO

BACKGROUND/PURPOSE: Irritancy levels of surfactants on human skin have not been clarified completely. The relationships between skin damage and changes of skin properties caused by various surfactants were investigated using non-invasive measurements. METHODS: Aqueous solutions of seven kinds of anionic, non-ionic, and amphoteric surfactants were exposed to the inside of forearm skin of 20 human subjects in two separate studies using the cup method. Hydration of the stratum corneum (SC), transepidermal water loss (TEWL), pH, skin surface roughness, and contents of the SC were measured before and after one exposure and after five and nine consecutive exposures to various surfactants. The discontinuation ratio of subjects for testing in each surfactant was determined by skin irritation symptoms and was defined as the degree of skin damage. RESULTS: Significant changes were observed only in hydration, TEWL, and natural moisturizing factors (NMF) content in the SC following surfactant exposure. A significant correlation was observed between the discontinuation ratio of each surfactant and the changes of hydration, TEWL, and NMF. Especially, the change of SC hydration showed an excellent correlation with the discontinuation ratio both for single (r = 0.942, P < 0.001) and for chronic exposures (r = 0.934, P < 0.001). CONCLUSION: Our results indicate that the change of hydration of the SC is equivalent to the skin damage caused by surfactants, and therefore is the most suitable indicator to evaluate the irritation of surfactants on the skin.


Assuntos
Água Corporal/efeitos dos fármacos , Toxidermias/metabolismo , Pele/efeitos dos fármacos , Pele/metabolismo , Tensoativos/efeitos adversos , Perda Insensível de Água/efeitos dos fármacos , Adulto , Água Corporal/metabolismo , Toxidermias/etiologia , Toxidermias/patologia , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Pele/patologia , Absorção Cutânea/efeitos dos fármacos , Propriedades de Superfície , Adulto Jovem
5.
J Dent Res ; 86(10): 974-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17890674

RESUMO

Destruction of cementum and alveolar bone is the main causative event for the exfoliation of teeth as a consequence of periodontitis. Prostaglandin E(2) (PGE(2)) and PGE receptor subtypes (EPs) play an important role in modulating osteoblast-mediated osteoclastogenesis; however, no information is available on the role of PGE(2) and EPs in regulating cementoblast-mediated cementoclastogenesis. We hypothesized that the PGE(2)-EPs pathway also regulates cementoblasts' ability to activate cementoclasts. For these studies, OCCM-30 cells (a mouse cementoblast cell line) were exposed to PGE(2) and specific EP agonists. PGE(2) (100 ng/mL) and EP4 agonist (1 microM) up-regulated RANKL and IL-6 mRNA levels, while they down-regulated OPG mRNA expression. The EP4 antagonist (1 microM) eliminated these effects of PGE(2). PGE(2) treatment of co-cultures of OCCM-30 cells with bone marrow cells induced TRAP-positive cells via the EP4 pathway. These findings suggest that PGE(2) promotes cementoblast-mediated cementoclastogenesis by regulating the expression of RANKL and OPG via the EP4 pathway.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Cemento Dentário/metabolismo , Dinoprostona/fisiologia , Osteoclastos/fisiologia , Receptores de Prostaglandina E/metabolismo , Animais , Células da Medula Óssea , Linhagem Celular Transformada , Técnicas de Cocultura , Cemento Dentário/fisiopatologia , Interleucina-6/biossíntese , Camundongos , Osteoprotegerina/biossíntese , Ligante RANK/biossíntese , Receptores de Prostaglandina E Subtipo EP4 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
6.
J Natl Cancer Inst ; 78(1): 19-28, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3025503

RESUMO

Expression of blood group ABH, Lewis, and sialylated-Lea antigens in human hepatocellular carcinomas and the adjacent nontumorous liver tissues was investigated with the use of seven monoclonal antibodies against these carbohydrate determinants. Chromatogram antibody-binding assay and solid-phase enzyme immunoassay of the upper-phase neutral glycolipids revealed the tumor-associated expression of blood group A-active glycolipids incompatible with blood-type status of the patients, a blood group A-active glycolipid with mobility on thin-layer chromatography between the known 6- and 8-sugar blood group A-active glycolipids in human erythrocytes, blood group H-active glycolipids, and blocked synthesis of Lea-active glycolipids with or without concomitant accumulation of Leb-active glycolipids. Immunohistochemical analysis of the fixed tissues with the use of an avidin-biotin-peroxidase complex method revealed blood group antigens in biliary epithelial cells but not in parenchymal liver cells. However, hepatocellular carcinoma cells in some cases expressed H and Leb antigens. Although only type 1 chain H antigen was detected in biliary epithelial cells, both type 1 and type 2 chain H antigens were found in hepatocellular carcinoma cells.


Assuntos
Sistema ABO de Grupos Sanguíneos/análise , Antígenos de Neoplasias/análise , Carcinoma Hepatocelular/imunologia , Antígenos do Grupo Sanguíneo de Lewis/análise , Neoplasias Hepáticas/imunologia , Anticorpos Monoclonais , Anticorpos Antineoplásicos , Ductos Biliares/imunologia , Cromatografia em Camada Fina , Epitélio/imunologia , Humanos , Fígado/imunologia
7.
Cancer Res ; 51(9): 2425-9, 1991 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1826632

RESUMO

O6-Alkylguanine-DNA alkyltransferase (AGT) activity was assayed in the extracts of 47 cell strains originating from mouse skin tumors induced by UV irradiation. They were also examined for the sensitivity to 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride by colony formation. The AGT activity (fmol/mg protein) of the tumor cell strains varied widely and the mean +/- SE was 72.5 +/- 9.37, while the AGT activity of the nontumor cell strains was 134 +/- 17. Among 47 strains, 6 strains showed extremely low or no AGT activity, about 5 fmol/mg protein or less, and were hypersensitive to 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride. Long-term culture of the tumor cells did not change the AGT activity except in some strains which might have had coexisting normal cells in the population in early passages. All strains showed similar UV sensitivity regardless of AGT activity. This is the first report which demonstrates that about 13% of newly induced tumor cell strains are deficient in AGT activity similar to Mer-/Mex- phenotype that was found in approximately 20% of the established human tumor cell strains.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Escherichia coli , Proteínas de Neoplasias/metabolismo , Neoplasias Induzidas por Radiação/enzimologia , Neoplasias Cutâneas/enzimologia , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Camundongos , Camundongos Pelados , Neoplasias Induzidas por Radiação/tratamento farmacológico , Nimustina/farmacologia , O(6)-Metilguanina-DNA Metiltransferase , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/etiologia , Organismos Livres de Patógenos Específicos , Fatores de Tempo , Fatores de Transcrição , Células Tumorais Cultivadas/enzimologia
8.
Cancer Res ; 51(23 Pt 1): 6219-23, 1991 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1834328

RESUMO

A shuttle vector plasmid, pYZ289, was constructed from the pZ189 plasmid and polyoma virus DNA. The plasmid contains a supF gene as a marker of mutation and can replicate in both Escherichia coli and mouse cells. The pYZ289 plasmids treated with N-methyl-N-nitrosourea were passed through mouse cells originating from skin tumors, which are either proficient (HL18) or deficient (HL8) in O6-methylguanine-DNA methyltransferase activity, and mutations in the supF gene were analyzed. In the repair-deficient HL8 cells, N-methyl-N-nitrosourea-treated pYZ289 showed lower plasmid survival and higher mutation frequency than in the repair-proficient HL18 cells. DNA sequence analysis in the mutated supF gene revealed that most mutations occurred in G:C base pairs (86% for HL8, 76% for HL18), and the frequency of G:C----A:T transition was higher in HL8 cells (69%) than in HL18 cells (31%). G:C----T:A transversions occurred more frequently in HL18 cells (31%) than in HL8 cells (12%). Mutations occurred frequently at the base pair positions of 123 and 159 of supF gene in HL18 cells and at 169 in HL8 cells. Analysis of the bases neighboring the mutations appeared to be related to the mutability of the base pairs with the sequence of 5'-purine-G-G-3' being the most frequently mutated. These results show that the new pYZ289 plasmid is useful for the analysis of mutations and that a deficiency in O6-methylguanine-DNA methyltransferase enhances the N-methyl-N-nitrosourea-induced mutation with significant specificity.


Assuntos
Metilnitrosoureia/toxicidade , Metiltransferases/deficiência , Mutação/genética , Plasmídeos/genética , Transfecção , Animais , Sequência de Bases , Linhagem Celular Transformada , Relação Dose-Resposta a Droga , Genes Virais/genética , Camundongos , Camundongos Pelados , Dados de Sequência Molecular , O(6)-Metilguanina-DNA Metiltransferase , Organismos Livres de Patógenos Específicos
9.
Cancer Res ; 57(20): 4637-41, 1997 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9377580

RESUMO

Members of cutaneous melanoma (CM) families with dysplastic nevi (DN) are at high risk of developing CM. Using a shuttle vector plasmid, pSP189, cell lines from three patients with CM plus DN were previously found to have elevated post-UV plasmid mutability. To investigate familial occurrence of this cellular phenotype, we examined post-UV plasmid mutability in 31 lymphoblastoid cell lines from 6 familial CM kindreds. In comparison to 16 normal control lines, we found an abnormally elevated post-UV plasmid mutability in cell lines from 13 of 13 patients with CM plus DN (P = 1.5 x 10(-8)) and from 5 of 8 patients with DN only (P = 0.001). Elevated spontaneous plasmid mutation frequency (MF) was also present in cell lines from six of the CM plus DN patients (P = 0.002) and three of the DN-only patients (P = 0.028). However, cell lines from two patients with CM without DN had normal post-UV plasmid MF. Although not specific for CM patients, of 27 cell lines with elevated post-UV plasmid MF, only 8 were from donors who did not have CM + DN or DN (19 of 24 versus 8 of 28; P = 0.0003). This study indicates that post-UV plasmid hypermutability is a laboratory marker for members of melanoma-prone families and suggests that patients with familial CM have a defective mechanism for handling UV-induced DNA damage.


Assuntos
Síndrome do Nevo Displásico/genética , Melanoma/genética , Mutagênese , Plasmídeos/efeitos da radiação , Neoplasias Cutâneas/genética , Raios Ultravioleta , Fatores Etários , Linhagem Celular Transformada , Reparo do DNA , Família , Vetores Genéticos , Herpesvirus Humano 4 , Humanos , Linfócitos , Testes de Mutagenicidade , Células Tumorais Cultivadas , Xeroderma Pigmentoso/genética
10.
Int J Cosmet Sci ; 27(5): 283-90, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18492210

RESUMO

Lower eyelid sags as well as wrinkles represent age-related morphological changes of the skin surface. However, a quantitative method to evaluate lower eyelid sagging has not been previously established. We designed a new quantitative evaluation method that uses non-invasive skin scanning, which is based on the difference between the superficial dimension of the sagging surface of the lower eyelid and the dimension of its projection area. In 97 females, 2-D and the 3-D images were taken. By 3-D image analysis, the difference between the superficial dimension of the sagging surface of the lower eyelid and the dimension of its virtual projection area was assessed, and was defined as the sag parameter. This parameter was significantly correlated with the sag score (a photographic scale to assess the degree of sagging) and with aging. The accuracy of the sag parameter was confirmed in a clinical test using a sag treatment lotion and a placebo lotion. The sag score decreased in skin treated with the sag treatment lotion, but the change was not significantly different from that of the placebo treated skin. On the contrary, the sag parameter was significantly reduced (P < 0.05) after topical application of the sag treatment lotion compared with the placebo-treated skin. These results indicate that the sag parameter as proposed herein is useful in clinical studies to evaluate slight changes in lower eyelid sagging.

11.
Eur J Clin Nutr ; 69(6): 693-6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25669318

RESUMO

BACKGROUND/OBJECTIVES: Xeroderma pigmentosum (XP) is a rare autosomal recessive disease characterized by defective repair of ultraviolet (UV) irradiation-induced DNA damage and high risk of skin cancer. Thus, these patients require strict photoprotection. Considering the importance of UV-mediated cutaneous vitamin D production, such rigorous photoprotection would cause vitamin D deficiency. Then, we have studied the vitamin D status in patients with XP-A, a group requiring the most strict photoprotection. SUBJECTS/METHODS: Twenty-one patients with XP-A (aged 6-25) were evaluated for their vitamin D intake, serum levels of 25-hydroxy-vitamin D (25OHD) and parathyroid hormone (PTH). Vitamin D intake was assessed by a 2-day food weighing method. RESULTS: Median dietary intake of vitamin D was 4.1 µg/day, and the median concentrations of serum 25OHD and PTH were 7.7 and 49.9 pg/ml, respectively. In 76% of the patients, serum 25OHD level was lower than 10 ng/ml, indicating vitamin D deficiency. Vitamin D intake and serum 25OHD level were significantly lower in patients under enteral nutrition (EN) than those with oral intake (OI). Multivariate analyses revealed that EN was a significant predictor of decreased serum 25OHD level (ß coefficient=-0.59, P=0.03). CONCLUSIONS: Vitamin D deficiency is highly prevalent in XP-A patients, and supplementation should be considered to avoid unfavorable skeletal consequences in these patients. In addition, determination of dietary vitamin D requirement has been a difficult work issue in the decision of dietary reference intakes (DRIs) because of its cutaneous production. Data from XP patients would yield useful information for the determination of DRIs for vitamin D.


Assuntos
Estilo de Vida , Estado Nutricional , Cooperação do Paciente , Neoplasias Cutâneas/prevenção & controle , Protetores Solares/uso terapêutico , Deficiência de Vitamina D/etiologia , Xeroderma Pigmentoso/terapia , 25-Hidroxivitamina D 2/sangue , Adolescente , Adulto , Calcifediol/sangue , Criança , Terapia Combinada/efeitos adversos , Estudos Transversais , Feminino , Hospitais Universitários , Humanos , Japão/epidemiologia , Masculino , Ambulatório Hospitalar , Hormônio Paratireóideo/sangue , Prevalência , Risco , Neoplasias Cutâneas/etiologia , Protetores Solares/efeitos adversos , Deficiência de Vitamina D/epidemiologia , Xeroderma Pigmentoso/sangue , Xeroderma Pigmentoso/fisiopatologia , Adulto Jovem
12.
J Invest Dermatol ; 103(1): 7-12, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8027583

RESUMO

The diagnosis of the melanoma-prone disorder dysplastic nevus syndrome (DNS) is based currently on a combination of clinical and histopathologic examinations of patients. To develop a potential laboratory test for DNS, we utilized the observation that an ultraviolet light (UV)-treated mutagenesis plasmid shuttle vector has an abnormally increased frequency of mutations after transfection into lymphoblastoid cells from a patient with familial DNS. pSP189 (containing the bacterial suppressor tRNA gene supF as a marker for mutations and a gene for ampicillin resistance for selection) was treated with UV and transfected into familial DNS, xeroderma pigmentosum complementation group A (XP-A), and normal lymphoblastoid cells by electroporation or diethylaminoethyl (DEAE) dextran. Untreated plasmid pZ189K (containing a gene for kanamycin resistance) was co-transfected as an internal standard to reduce the variability of plasmid survival measurements. After 2 d, plasmids were extracted, used to transform an indicator strain of Escherichia coli, and assayed on plates containing ampicillin or kanamycin. Counting light blue or white colonies (containing mutated supF in the plasmid) and blue colonies (with wild type supF) permitted measurement of the plasmid survival and mutation frequency. Transfection by electroporation or DEAE dextran resulted in abnormally reduced survival of UV-treated plasmid after passage through the XP-A but normal survival in the three DNS lines. Transfection of UV-treated plasmid by DEAE dextran yielded a greater hypermutability with the familial DNS lines than by electroporation. These results suggest that pSP189 UV hypermutability with normal UV survival using DEAE dextran transfection may form the basis of a potential laboratory assay for familial DNS.


Assuntos
Síndrome do Nevo Displásico/diagnóstico , Síndrome do Nevo Displásico/genética , Mutação , Testes Diagnósticos de Rotina , Genes Supressores , Vetores Genéticos , Humanos , Plasmídeos , RNA de Transferência/genética , Raios Ultravioleta
13.
J Invest Dermatol ; 117(3): 671-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11564175

RESUMO

We previously reported that wrinkle formation in the skin following long-term ultraviolet B irradiation is accompanied by decreases in skin elasticity and the curling of elastic fibers in the dermis. We further showed that wrinkles could be repaired by treatment with retinoic acid and that this was concomitant with the recovery of skin elasticity ascribed to the repair of damaged elastic fibers. Those studies suggested that decreasing the tortuosity of dermal elastic fibers is an important factor involved in inhibiting or repairing wrinkle formation. Therefore, it is of particular interest to determine whether the inhibition of elastase activity in vivo would prevent the damage of dermal elastic fibers and might abolish wrinkle formation associated with the loss of skin elasticity. Because the major elastase in the skin under noninflammatory conditions is skin fibroblast elastase, we used a specific inhibitor of that enzyme to assess its biologic role in wrinkle formation. The hind limb skins of Sprague-Dawley rats were irradiated with ultraviolet B at a suberythemal dose three times a week for 6 wk. During that period, 0.1-10.0 mM N-phenetylphosphonyl-leucyl-tryptophane, an inhibitor of skin fibroblast elastase, was applied topically five times a week. N-phenetylphosphonyl-leucyl-tryptophane application at concentrations of 0.1-1.0 mM abolished wrinkle formation in a concentration-dependent manner, with a peak for inhibition at 1.0 mM. This inhibition was accompanied by a continued low tortuosity of dermal elastic fibers and a maintenance of skin elasticity. Measurement of elastase activity after 6 wk of ultraviolet B irradiation demonstrated that whereas phosphoramidon-sensitive elastase activity was significantly enhanced in the ultraviolet B-exposed skin, there was no significant increase in that activity in the ultraviolet B-exposed, N-phenetylphosphonyl-leucyl-tryptophane-treated skin. These findings suggest that skin fibroblast elastase plays an essential part in the degeneration and/or tortuosity of elastic fibers induced by cumulative ultraviolet B irradiation.


Assuntos
Inibidores Enzimáticos/farmacologia , Elastase Pancreática/antagonistas & inibidores , Animais , Dipeptídeos/farmacologia , Relação Dose-Resposta a Droga , Fibroblastos/enzimologia , Fibroblastos/patologia , Fibroblastos/efeitos da radiação , Masculino , Ratos , Ratos Sprague-Dawley , Pele/enzimologia , Pele/patologia , Pele/efeitos da radiação , Raios Ultravioleta
14.
J Invest Dermatol ; 101(1): 69-72, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8101209

RESUMO

This study was performed to elucidate whether xeroderma pigmentosum complementation group A (XPA) carrier has DNA repair abnormality against sun-exposure and ultraviolet (UV)-mimetic chemical carcinogen 4-nitroquinoline 1-oxide (4NQO). Here we report three sporadic cases of XP that were defined as group A by genetic complementation test as well as polymerase chain reaction (PCR) analysis to detect the point mutation in the responsible gene for XPA. DNA repair analyses in the skin fibroblasts revealed that the cells from the patients were much more sensitive to UV and 4NQO and had extremely low UV-induced unscheduled DNA synthesis (UDS) than control cells, whereas the cells from the carriers (heterozygotes of XP) had sensitivity to UV and 4NQO and levels of UV-induced UDS similar to normal cells. These results indicate that the obligate heterozygotes, despite having a mutated allele in XPA complementing gene demonstrated by PCR, have no DNA repair abnormality after UV irradiation and UV-mimetic 4NQO treatment. Our observations imply that XPA heterozygotes do not have higher risk of skin cancers than normal subjects based on their DNA repair abnormality.


Assuntos
Reparo do DNA , Xeroderma Pigmentoso/genética , 4-Nitroquinolina-1-Óxido/farmacologia , Sequência de Bases , Pré-Escolar , DNA/biossíntese , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/efeitos da radiação , Heterozigoto , Humanos , Lactente , Masculino , Sondas Moleculares/genética , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , Raios Ultravioleta , Xeroderma Pigmentoso/classificação , Xeroderma Pigmentoso/patologia
15.
J Invest Dermatol ; 113(2): 202-8, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10469304

RESUMO

8-Methoxypsoralen plus ultraviolet A light is suggested to shift T lymphocytes from Th2 to Th1 cells. To clarify this issue, we examined the effects of 8-methoxypsoralen/ultraviolet A on the expression/production of cytokines in peripheral blood mononuclear cells from normal subjects and a Sézary syndrome patient. 8-Methoxypsoralen/ultraviolet A augmented the expression of mRNAs for interferon-gamma and interleukin-2 and reduced those for interleukin-4 and interleukin-10. It seems that this enhancement of Th1 cytokines is caused by increment of cytokine production by Th1 cells but not by conversion of Th2 cells to produce Th1 cytokines. The number of interferon-gamma-secreting lymphocytes was markedly increased in 8-methoxypsoralen/ultraviolet A-treated peripheral blood mononuclear cells 20 h after treatment, whereas that of Th2 cytokine-producing cells was decreased. Accordingly, the amount of interferon-gamma was elevated in culture supernatants from 8-methoxypsoralen-phototreated peripheral blood mononuclear cells, whereas interleukin-4 was significantly reduced. This enhanced production of interferon-gamma, however, was found only until 3 d after 8-methoxypsoralen phototreatment and was declined by 5 d after treatment. Finally, 8-methoxypsoralen/ultraviolet A treatment of T cells regulated their ability to induce keratinocyte CD54 expression. Our results show that 8-methoxypsoralen/ultraviolet A has a transient but biologically active Th1-skewing action in human T cells, suggesting that 8-methoxypsoralen/ultraviolet A exerts a beneficial therapeutic effect on Th2-mediated or Th2-malignant diseases.


Assuntos
Citocinas/metabolismo , Linfócitos T/efeitos dos fármacos , Células Th1/metabolismo , Citocinas/genética , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Interferon gama/sangue , Interleucina-4/sangue , Queratinócitos/metabolismo , Leucócitos Mononucleares/citologia , Metoxaleno/uso terapêutico , Pessoa de Meia-Idade , Terapia PUVA , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Células Th2/fisiologia
16.
J Invest Dermatol ; 103(5 Suppl): 96S-101S, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7963692

RESUMO

Xeroderma pigmentosum, Cockayne syndrome, the xeroderma pigmentosum-Cockayne syndrome complex, and trichothiodystrophy cells have defects in DNA repair and are associated with clinical and cellular hypersensitivity to ultraviolet radiation (UV). Familial dysplastic nevus syndrome cells have UV hypermutability. Although xeroderma pigmentosum and dysplastic nevus syndrome have markedly increased cancer risk. Cockayne syndrome and trichothiodystrophy do not. At the molecular level, these disorders are associated with several different genetic defects as evidenced by the existence of multiple overlapping complementation groups. Recent progress has been made in identifying the chromosomal location and cloning the defective genes in these disorders. Using plasmid shuttle vectors we have shown abnormal repair and mutagenesis of DNA damaged by 254-nm (UVC) or 295-nm (UVB) radiation or the chemical carcinogen aflatoxin in cells from patients with xeroderma pigmentosum. Although xeroderma pigmentosum cells are defective in repair of all photoproducts, Cockayne syndrome cells appear to be defective in repair of cyclobutane dimers and have normal repair of nondimer photoproducts. DNS cells have post UV plasmid hypermutability. These diseases may serve as models for examining molecular mechanisms of carcinogenesis in humans.


Assuntos
Reparo do DNA , Ligação Genética , Neoplasias/genética , Xeroderma Pigmentoso/genética , Síndrome de Cockayne/genética , Síndrome do Nevo Displásico/genética , Cabelo/anormalidades , Humanos
17.
J Invest Dermatol ; 107(4): 647-53, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8823375

RESUMO

Xeroderma pigmentosum (XP)/Cockayne syndrome (CS) complex is a combination of clinical features of two rare genetic disorders in one individual. A sun-sensitive boy (XP20BE) who had severe symptoms of CS, with dwarfism, microcephaly, retinal degeneration, and mental impairment, had XP-type pigmentation and died at 6 y with marked cachexia (weight 14.5 lb) without skin cancers. We evaluated his cultured cells for characteristic CS or XP DNA-repair abnormalities. The level of ultraviolet (UV)-induced unscheduled DNA synthesis was less than 5% of normal, characteristic of the excision-repair defect of XP. Cell fusion studies indicated that his cells were in XP complementation group G. His cells were hypersensitive to killing by UV, and their post-UV recovery of RNA synthesis was abnormally low, features of both CS and XP. Post-UV survival of plasmid pSP189 in his cells was markedly reduced, and post-UV plasmid mutation frequency was higher than with normal cells, as in both CS and XP. Sequence analysis of the mutated plasmid marker gene showed normal frequency of plasmids with multiple base substitutions, as in CS, and an abnormally increased frequency of G:C-->A:T mutations, a feature of XP. Transfection of UV-treated pRSVcat with or without photoreactivation revealed that his cells, like XP cells, could not repair either cyclobutane pyrimidine dimers or non-dimer photoproducts. These results indicate that the DNA-repair features of the XP20BE (XP-G/CS) cells are phenotypically more like XP cells than CS cells, whereas clinically the CS phenotype is more prominent than XP.


Assuntos
Síndrome de Cockayne/complicações , Síndrome de Cockayne/genética , Reparo do DNA , Mutagênese , Raios Ultravioleta/efeitos adversos , Xeroderma Pigmentoso/complicações , Xeroderma Pigmentoso/genética , Sobrevivência Celular/efeitos da radiação , Criança , Síndrome de Cockayne/patologia , DNA/efeitos da radiação , Fibroblastos/efeitos da radiação , Teste de Complementação Genética , Humanos , Masculino , Plasmídeos/genética , RNA/biossíntese , Xeroderma Pigmentoso/patologia
18.
Semin Oncol ; 24(2 Suppl 6): S6-71-S6-80, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9151920

RESUMO

Combination therapy consisting of Lipiodol (Laboratoire Guerbet, Villepinte, France) containing styrene maleic acid neocarzinostatin and transcatheter arterial embolization (L-TAE) has been an important conservative therapy for hepatocellular carcinoma (HCC). We examined the clinical and pathologic characteristics of 14 HCC cases that achieved total tumor necrosis in response to L-TAE. The HCCs of all cases were resected 45 +/- 17 days after L-TAE and were confirmed to be totally necrotic. Ultrasonography showed a mean tumor size of 2.5 +/- 1.0 cm, often with a halo formation around the tumor. Angiographically, neovascularity and clear tumor stains were observed in all cases. Computed tomography portography showed nodular perfusion defects in all the cases examined. There were portal invasions in two cases. On Lipiodol-computed tomography, Lipiodol was densely and homogeneously retained within the whole tumor. The number of tumors was single in all diagnostic images. Macroscopic view of HCCs were single nodular type in nine cases and single nodular type with extra growth in four cases. Clear capsular formation was seen in each HCC nodule. Soft x-rays were taken to observe the exact distribution of Lipiodol in the operative specimens. Microscopic intrahepatic metastases were found histologically in four cases. Histologic examination showed the trabecular pattern with broad blood spaces in which Lipiodol was positive with Sudan III staining. Necrosis was seen not only in the main tumor, but also in the capsular invasions and microscopic metastases with Lipiodol deposition. The characteristics of the cases with total tumor necrosis were as follows. Deposition of Lipiodol throughout the tumor was essential, and clinically the cases showed a single HCC tumor with a diameter of more than 5 cm and arterial hypervascularity. The pathologic findings included expansive growth with capsular formation and trabecular-type HCC with abundant blood spaces. These findings are important for evaluating the radical efficacy of L-TAE.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas/terapia , Anidridos Maleicos/administração & dosagem , Poliestirenos/administração & dosagem , Zinostatina/análogos & derivados , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Terapia Combinada , Feminino , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Necrose , Tomografia Computadorizada por Raios X , Zinostatina/administração & dosagem
19.
Cancer Lett ; 184(2): 207-14, 2002 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-12127693

RESUMO

A method for rapid fractionation of normal and leukemic T-cells (Jurkat, RPMI-8402, MOLT-4), using lectin-affinity column chromatography, is described. CNBr-activated Sepharose 6MB was used as a non-mobile phase. The gel was covalently conjugated with Dolichos biflorus agglutinin (DBA) over 24 h. The normal cells were eluted by phosphate buffered saline (Ca(2+) and Mg(2+) free), while the leukemic T-cells, interacting with DBA, were removed by N-acetyl-D-galactosamine or by low-concentrated acetic acid as a mobile phase. The cell fractions were detected spectrophotometrically at 600 nm. The rate of cell elution decreased in the order: normal>leukemic T-cells. The viability and the type of separated T-cell fractions were characterized by flow cytometry, using adequate fluorescent antibodies. The interactions between leukemic T-cells and DBA-saturated Sepharose beads were examined by fluorescent microscopy, using fluorescent isothiocyanate-DBA as a fluorescent marker.


Assuntos
Linfócitos T/imunologia , Células Tumorais Cultivadas/patologia , Antígenos CD/análise , Adesão Celular , Separação Celular/métodos , Cromatografia de Afinidade , Citometria de Fluxo , Humanos , Receptores de Hialuronatos/análise , Células Jurkat , Lectinas , Microscopia de Fluorescência , Valores de Referência , Linfócitos T/citologia , Linfócitos T/patologia , Antígenos Thy-1/análise , Células Tumorais Cultivadas/imunologia
20.
Am J Med Genet ; 101(2): 153-7, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11391659

RESUMO

We report a Japanese woman with de novo 6p monosomy and 10q trisomy [46,XX,der(6)t(6;10)(p25.1;q25.2)] whose clinical manifestations resemble those of xeroderma pigmentosum (XP) and Cockayne syndrome (CS), known as premature aging syndromes. She had a history of easy sunburning and presented a number of freckles and hypopigmented spots on her face as those of XP. Magnetic resonance imaging and computed tomography scanning demonstrated intracranial abnormalities like those seen in CS. DNA repair studies using the patient's fibroblasts demonstrated hypersensitive responses to ultraviolet (UV). XP, CS, and UV-sensitive syndromes with photosensitivity disturbances have been known as DNA repair abnormalities. However, an association of 6p monosomy with these diseases has not been reported so far. Molecular analysis of the patient we described may contribute to the identification of novel DNA-repair-related gene(s) and/or to the senile mechanism.


Assuntos
Transtornos de Fotossensibilidade/patologia , Translocação Genética , Adulto , Sobrevivência Celular/efeitos da radiação , Bandeamento Cromossômico , Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 6/genética , Reparo do DNA , Relação Dose-Resposta à Radiação , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos da radiação , Humanos , Cariotipagem , Transtornos de Fotossensibilidade/etiologia , Pele/citologia , Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA