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1.
J Eur Acad Dermatol Venereol ; 34(10): 2436-2444, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32170979

RESUMO

BACKGROUND: Intralesional 5-fluorouracil (5-FU) in combination with triamcinolone acetonide (TAC) has been recommended as a promising alternative for keloids not responding to silicone-based products, cryotherapy or intralesional corticosteroids alone. Although numerous studies support the efficacy of this regime, there is a lack of objective data. OBJECTIVES: In this study, we evaluate the therapeutic effect of four courses of intralesional 5-FU in combination with TAC (3 : 1) utilizing 3D analysis (PRIMOS®pico ), ultrasound and scar scales such as the Patient and Observer Scar Assessment Scales (POSAS) and the Dermatology Life Quality Index (DLQI). METHODS: Twenty-five patients with keloids were treated using 5-FU and TAC every 4 weeks. Objective assessments were performed and the scar scales administered at baseline, as well as during consecutive visits at 1- and 12-month follow-up (FU). Routine laboratory tests were performed at baseline and at 1-month FU. RESULTS: 3D PRIMOS and ultrasound measurements revealed highly significant and stable reductions in height (baseline mean score: 4.0 ± 1.7 mm, 1-month FU mean score: 1.5 ± 0.8 mm, 12-month FU mean score: 1.8 ± 0.9 mm, P = <0.0001), volume (baseline mean score: 1,105 ± 911.5 mm3 , 1-month FU mean score: 416.1 ± 218.1 mm3 , 12-month FU mean sore: 431.2 ± 253.6 mm3 , P = <0.0001, respectively) and penetration depth of keloids (relative reduction between baseline and 12-month FU of 74.4%, P = <0.0001). The POSAS and DLQI scales confirmed significant objective and subjective improvements in scar appearance in all categories. The life quality associated with keloid appearance improved from a 'moderate effect' to a 'small effect' throughout the course of the study. CONCLUSIONS: Results of this study confirm the efficacy and safety of the combination of 5-FU and TAC in keloids. Treatments were well tolerated and demonstrated stable results at 12-month FU.


Assuntos
Queloide , Fluoruracila/uso terapêutico , Humanos , Injeções Intralesionais , Queloide/tratamento farmacológico , Queloide/patologia , Resultado do Tratamento , Triancinolona Acetonida/uso terapêutico
2.
J Eur Acad Dermatol Venereol ; 30(4): 677-82, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25758344

RESUMO

BACKGROUND: Anhidrotic ectodermal dysplasia (AED) is an inherited syndrome, which originates mainly from genetic alteration of the ectodysplasin A (EDA) gene. It regularly affects the adnexa of the skin which results in a characteristic phenotype of the patients including hypo- or anhidrosis leading to severe disturbances in the regulation of body temperature. OBJECTIVES: To prevent the development of the symptoms in early childhood promising therapeutic approaches are currently under clinical investigation. In this context, timely diagnosis of this genetic syndrome is crucial. The purpose of our study was the investigation of modern non-invasive imaging methods such as optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) in the immediate diagnosis of AED. METHODS: We examined a 3-year-old boy with the suspicion for an AED syndrome and his family members with RCM and OCT to document presence and characteristic features of sweat glands in comparison to non-affected individuals. RESULTS: The patient and the affected brother showed significantly reduced sweat glands in the imaging compared to the controls. The genetic analysis revealed a mutation of the EDA gene for hemizygosity previously associated with AED and the mother was revealed as the conductor of the genetic alteration. CONCLUSIONS: With the help of non-invasive imaging, we were able to detect sweat gland dysplasia in the affected family members without performing a biopsy which led us to the diagnosis of an AED. The application of modern dermatological imaging techniques might serve as valuable supplementary tools in the immediate, non-invasive diagnosis of genetic syndromes especially in newborns when early therapeutic approaches are planned.


Assuntos
Displasia Ectodérmica/complicações , Família , Microscopia Confocal/métodos , Doenças das Glândulas Sudoríparas/diagnóstico , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Pré-Escolar , Displasia Ectodérmica/genética , Feminino , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
3.
J Eur Acad Dermatol Venereol ; 29(11): 2112-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25866177

RESUMO

BACKGROUND: Measuring quality of life through questionnaires is a common method to evaluate the impact of different afflictions on the patient's well-being, especially in the field of dermatology where appearance changing afflictions are common. OBJECTIVES: A variety of questionnaires has been used to distinguish different skin conditions like psoriasis, atopic dermatitis and scars. Using the Dermatology Life Quality Index (DLQI), we investigated different scar types regarding their impact on quality of life. METHODS: We assessed the quality of life in 130 patients presenting to our outpatient scar clinic for the first time using the DLQI. Scars were analysed according to their clinical appearance (physiological scars, keloids, hypertrophic scars, atrophic scars, self-harm scars). Physiological scars were established as a baseline for further comparison between groups. RESULTS: Patients in the physiological scar group scored a mean DLQI score of 2.07 ± 3.56, patients in the keloid-, hypertrophic scar-, atrophic scar- and self-harm scar group scored values of 6.06 ± 4.00, 2.53 ± 2.48, 7.26 ± 6.72 and 12.00 ± 3.85 respectively. When compared to the baseline group the difference in the overall score for keloids was +3.99 (P < 0.001), hypertrophic scars scored +0.45 (ns), atrophic scars +5.19 (P < 0.01) and self-harm scars +9.93 (P < 0.001). CONCLUSION: Using the DLQI, we could demonstrate that different subsets of pathological scars do affect patients in a different magnitude. The DLQI provides a promising adjunct for quantifying the quality of life in patients suffering from keloids, atrophic- and self-harm scars and may constitute an interesting additional tool for monitoring the progress of scar treatments.


Assuntos
Cicatriz/psicologia , Qualidade de Vida/psicologia , Pele/patologia , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Atrofia/patologia , Cicatriz/etiologia , Cicatriz/patologia , Cicatriz Hipertrófica/psicologia , Feminino , Humanos , Queloide/psicologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Comportamento Autodestrutivo/complicações , Adulto Jovem
5.
J Neurol ; 248(10): 866-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11697523

RESUMO

In an open label study, we administered riluzole (50 mg twice a day) to nine patients with genetically confirmed Huntington's disease (HD) (clinical stages 1-3; mean age 46.4 (SD 9.3) years; mean disease duration 8 (SD 3.3) years). The study was designed to evaluate (1) safety and tolerability of riluzole and (2) effects of riluzole on motor impairment, functional disability, cognitive impairment, and behavioral abnormalities using the Unified HD Rating Scale. Patients were evaluated at baseline and after three and twelve months of riluzole therapy. Laboratory tests (hematology and liver enzymes) were repeated monthly. All adverse experiences, reported spontaneously or observed directly by the investigator, were recorded. Riluzole was well tolerated. No increase of serum liver enzymes was seen throughout the study in all but one patient showing a mild elevation. At three months, mean total motor scale (TMS), mean TMS chorea subscore, and mean total functional capacity scale were significantly improved compared with baseline. At twelve months, however, this beneficial effect on motor status and overall function was not sustained. In contrast, severity and frequency of behavioral dysfunction as well as psychomotor speed assessed by the symbol digit modalities test were improved compared with baseline. Our data suggest that there are transient antichoreatic effects and more sustained effects of riluzole on psychomotor speed and behavior in patients with HD. A double-blind, placebo-controlled trial appears highly warranted to establish definitely the symptomatic versus neuroprotective actions of riluzole in HD.


Assuntos
Doença de Huntington/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Riluzol/uso terapêutico , Administração Oral , Adulto , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Doença de Huntington/psicologia , Masculino , Pessoa de Meia-Idade , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/efeitos adversos , Desempenho Psicomotor/fisiologia , Riluzol/administração & dosagem , Riluzol/efeitos adversos
6.
Neurology ; 53(4): 801-6, 1999 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-10489044

RESUMO

OBJECTIVE: To review the direct DNA testing for Huntington's disease (HD) in Germany, Switzerland, and Austria from 1993 to 1997, and to analyze the population with regard to age structure, gender, and family history. METHODS: Twelve laboratories (nine in Germany, two in Austria, and one in Switzerland) recorded data pertaining to repeat number, gender, age at molecular diagnosis, and family history of probands. The molecular test was categorized as either diagnostic (for symptomatic individuals), presymptomatic (for individuals at risk), and prenatal (for pregnancies at risk). RESULTS: A total of 3,090 HD patients, 992 individuals at risk, and 24 fetuses were investigated using DNA analysis. The clinical diagnosis was confirmed in 65.6% of patients. A total of 38.5% of individuals at risk inherited an expanded CAG repeat. The female-to-male ratio showed a distinct predominance of women both in the diagnostic and presymptomatic groups. Of the fetuses tested, six were carriers of an expanded CAG repeat. Two pregnancies were interrupted; one pregnancy was not. No information about the parents' decision was obtained for the remaining three pregnancies. CONCLUSIONS: Approximately 20% of the estimated 10,000 HD patients living in Germany, Switzerland, and Austria have been identified by DNA analysis (total population, approximately 100 million; incidence of HD, 1:10,000). Assuming a ratio of HD patients to individuals at risk of 1:3, approximately 30,000 individuals are, in principle, eligible for a presymptomatic test. Less than 3 to 4% of individuals at risk have requested a presymptomatic test. This shows that the assumed enormous request of predictive testing has not occurred. More surprisingly, prenatal diagnoses were found to be rare.


Assuntos
DNA/análise , Doença de Huntington/genética , Adulto , Idoso , Alelos , Áustria , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Suíça , Sequências de Repetição em Tandem
7.
Neurology ; 52(4): 849-51, 1999 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-10078738

RESUMO

The authors found a strong geographic cluster of spinocerebellar ataxia type 6 (SCA6) families in the Northrhine-Westfalia area, suggesting a founder effect in the German SCA6 population. Genotyping with DNA markers linked to the CACNL1A4 gene on chromosome 19p13 revealed a common haplotype and shared allelic characteristics in the majority of German families. The observed founder effect may be related to the relative meiotic stability of CAG repeats in this type of autosomal dominant cerebellar ataxia.


Assuntos
Efeito Fundador , Degenerações Espinocerebelares/genética , Alelos , Cromossomos Humanos Par 19/genética , Alemanha , Haplótipos , Humanos
8.
Hum Genet ; 100(3-4): 431-40, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9272168

RESUMO

Repeated chromosomal analysis of peripheral blood lymphocytes and skin fibroblasts from a woman referred for amenorrhoea, streak gonads, hyperthyroidism, adiposity and elevated alpha-fetoprotein levels but no other manifestations of known chromosomal breakage syndromes demonstrated an increased spontaneous chromosomal breakage rate (ISCBR). Chromatid and chromosomal breaks were more numerous than sporadic rearrangements and dicentric chromosomes. Exposure of the cells to mitomycin C, diepoxybutane, X-rays or UV irradiation induced an increase in chromosomal and chromatid abnormalities over that in controls. A micronucleus assay demonstrated an increase in the incidence of formation of micronuclei and the population doubling time of the fibroblasts of the proposita was delayed. Chromosomal analysis was performed on lymphocytes of the parents and of five sibs of the proposita. Two brothers had chromosomal abnormalities identical to those of the patient and elevated alpha-fetoprotein levels, however, without any clinical abnormalities. The parents were affected by only a moderate ISCBR whereas two brothers and one sister were chromosomally normal. The clinical, chromosomal and biochemical findings in this family represent a novel chromosomal instability syndrome.


Assuntos
Quebra Cromossômica , Infertilidade Feminina/genética , Adulto , Idoso , Células Cultivadas , Feminino , Humanos , Linfócitos/citologia , Masculino , Micronúcleos com Defeito Cromossômico , Pessoa de Meia-Idade , Linhagem , Síndrome , Fatores de Tempo
9.
Hum Genet ; 99(6): 710-9, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9187662

RESUMO

The molecular defect of the hereditary disease Fanconi anemia (FA) remains unknown. The two theoretical possibilities are (1) an impaired DNA crosslink-repair system or (2) a disturbed oxygen metabolism either by overproduction of reactive oxygen intermediates (ROI) or by diminished detoxification of ROI. In order to gain further insight into the molecular mechanism of this disease, we have determined the repair capacity of FA cells challenged by crosslinking agents and have analyzed diverse biological systems that are involved in oxygen metabolism. We have tested normal and FA cells for oxygen consumption and for the activity of the antioxidant phospholipid-hydroperoxide-glutathione-peroxidase (PHGPx). FA cells show a reduced oxygen consumption and an increased PHGPx activity. Since spontaneous and induced chromosomal instability is a main cellular feature of FA, we have analyzed the redox state of cells and the effect of cytochrome P-450 (Cyt P-450) inhibitors and inducers on chromosomal breaks and micronuclei production. Our results indicate that Cyt P-450 enzymes, especially Cyt P-450 1A2, play a crucial role in radical metabolism in FA cells. Furthermore, we have determined NF-kappa B activity in untransformed cells and in SV40-transformed cells by gel shift experiments. NF-kappa B is a multiunit transcription factor that is known to be induced by ROI and that activates the expression of various genes involved in cellular responses to stress. NF-kappa B is constitutively induced in SV40-transformed FA cells probably as a consequence of an increased ROI level. Our results suggest that enzymatic defects in oxygen metabolism mediate the FA phenotype via impaired reactivity with ROI. Cyt P-450 1A2 appears to be a good candidate for the defective enzyme, even though no differences have been measured in the activity of this enzyme in FA and control fibroblasts in pilot experiments.


Assuntos
Anemia de Fanconi/metabolismo , Oxigênio/metabolismo , Linhagem Celular , Sistema Enzimático do Citocromo P-450/metabolismo , Reparo do DNA , Resistência a Múltiplos Medicamentos/genética , Anemia de Fanconi/genética , Anemia de Fanconi/patologia , Fibroblastos/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , NF-kappa B/metabolismo , Oxirredução , Consumo de Oxigênio/genética , Fenótipo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Espécies Reativas de Oxigênio/metabolismo
10.
Eur J Hum Genet ; 5(6): 364-70, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9450180

RESUMO

Affected and unaffected members of a Caucasian family with Werner syndrome were analyzed for mutations in the recently described Werner syndrome (WRN) gene and for their relevance to phenotypic expression of chromosomal instability and x-ray hypersensitivity. Two distinct molecular alterations were documented in the family. Analysis of the genomic DNA revealed a single-base exchange from A to T at an intron-exon boundary in the otherwise strongly conserved 5' donor splice site. Consequently, exon 30 is spliced together with the intron. The ensuing structure could be confirmed by the presence and calculated size of the resulting RNA fragments. The patients, all compound heterozygotes, had a 1-bp deletion in the first third of the coding sequence in the other allele. The genotypes of the family members for these mutations were determined and consequences for the cellular phenotype of the otherwise unaffected heterozygotes are documented.


Assuntos
DNA Helicases/genética , Síndrome de Werner/genética , Adulto , Senilidade Prematura/genética , Áustria , Aberrações Cromossômicas , Quebra Cromossômica/genética , Análise Mutacional de DNA , Exodesoxirribonucleases , Feminino , Fibroblastos , Genótipo , Humanos , Linfócitos , Masculino , Testes para Micronúcleos , Linhagem , Fenótipo , Splicing de RNA , RNA Mensageiro/análise , RecQ Helicases , Helicase da Síndrome de Werner , População Branca , Raios X
11.
Mech Ageing Dev ; 88(1-2): 1-15, 1996 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-8803918

RESUMO

Werner syndrome is an inherited disease with symptoms of presenescence. The primary defect site either on the protein or at the DNA level is not known, nor is it possible to identify a heterozygous phenotype. On the basis of cellular peculiarities expressed in the homozygotes-lifespan reduction of cells in culture, length of population doubling time and chromosomal instability-we searched for a 'Werner-like' phenotype in otherwise phenotypically unaffected siblings. We established primary fibroblasts from eight members of a Tyrolean family, two of whom had been diagnosed as typical Werner syndrome, as well as from unrelated healthy young and old volunteers. Determination of the lifespan of each strain and studies on population doubling time and chromosomal instability revealed similar cellular characteristics in all family members, albeit to a lesser extent with the siblings than with the homozygotes when compared to age-matched controls. These features, also apparent in cultivated fibroblasts from old but healthy controls, appear to be indicative of Werner syndrome when expressed in young or middle aged persons. The possible identification of otherwise clinically healthy gene carriers of Werner syndrome is of utmost importance for genetic counselling and medical surveillance for this disorder.


Assuntos
Síndrome de Werner/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Divisão Celular , Células Cultivadas , Aberrações Cromossômicas , Transtornos Cromossômicos , Feminino , Fibroblastos/fisiologia , Fibroblastos/ultraestrutura , Humanos , Ácido Hialurônico/urina , Longevidade , Masculino , Micronúcleos com Defeito Cromossômico/ultraestrutura , Pessoa de Meia-Idade , Linhagem , Fenótipo , Fatores de Tempo , Síndrome de Werner/patologia , Síndrome de Werner/fisiopatologia
12.
Arzneimittelforschung ; 45(3): 342-4, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7741797

RESUMO

Autolysates of Lactobacillus gasseri were tested for their ability to improve repair capacity in cultured human fibroblasts. In the course of this research on molecular mechanisms of hereditary DNA repair deficiencies and presenility syndromes, a significant and reproducible effect on repair capacity in these cells by an autolysate of the gram-positive bacterium Lactobacillus gasseri was found.


Assuntos
Reparo do DNA , Lactobacillus/metabolismo , Adolescente , Adulto , Autólise , Núcleo Celular/química , Núcleo Celular/efeitos da radiação , Células Cultivadas , Síndrome de Cockayne/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Masculino , Raios Ultravioleta
13.
Electrophoresis ; 15(7): 941-52, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7813400

RESUMO

Aldoses, ketoses and uronic acids were derivatized successfully within 15 min at a temperature of 90 degrees C by reductive amination with 4-aminobenzonitrile. Subsequently, the derivatives were separated as their borate complexes by capillary zone electrophoresis, using 175 mM borate buffer, pH 10.5, as carrier. The electrophoretic mobilities were determined by the complex stability, which was found to depend on the number of hydroxyl groups on any given carbohydrate derivative, the presence of substituents, and most strongly on the configuration of the vicinal hydroxyl groups at C-3 and C-4 in aldoses and uronic acids, and with regard to ketoses on those at C-4 and C-5. Time of analysis could be reduced considerably by the use of micellar electrokinetic chromatography, which separated 4-aminobenzonitrile sugar derivatives on the basis of their differential partitioning into an electroendosmotically driven aqueous phase and into sodium dodecyl sulfate micelles. Optimum resolution was achieved with a Tris-phosphate buffer, pH 7.5, containing 100 mM of sodium dodecyl sulfate. The method made it possible to resolve several carbohydrates which had not been resolved successfully by means of capillary zone electrophoresis, such as glucose and fructose. Moreover, separation selectivity could be adjusted by varying the capillary temperature. Finally, on-column UV monitoring at 285 nm allowed the detection of glucose with a lower mass detection limit of 1 fmol and a concentration sensitivity of 0.3 microM.


Assuntos
Carboidratos/química , Cromatografia/métodos , Eletroforese/métodos , Nitrilas/química , Boratos/química , Isótopos de Carbono , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Micelas , Oxirredução , Prótons , Sensibilidade e Especificidade , Solubilidade , Temperatura , Água/química
14.
Mutat Res ; 316(1): 37-48, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7507567

RESUMO

Cellular aging appears to be related to and perhaps caused by diminished DNA repair. To elucidate direct correlations between DNA repair capacity and senescence various parameters of cellular aging and DNA repair were studied simultaneously. Of special interest are features of DNA repair and senescence in cultured diploid fibroblasts derived either from healthy young or elderly probands as well as from patients suffering from premature senescence syndromes (Werner syndrome, Cockayne syndrome, ataxia telangiectasia and Down syndrome). Here we demonstrate the striking parallelism between reduced maximal lifespan, elevated levels of spontaneous chromosomal breaks, higher incidence of formation of micronuclei, a significant prolongation of cell cycle duration and a diminished reactivation of in vitro injured plasmid after transfection in cells from old individuals and from patients with premature senescence syndromes, suggesting a causal relationship between senescence and DNA damage.


Assuntos
Senescência Celular/genética , Síndrome de Cockayne/genética , Reparo do DNA/fisiologia , Síndrome de Werner/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ataxia Telangiectasia/genética , Ataxia Telangiectasia/fisiopatologia , Ciclo Celular , Sobrevivência Celular , Criança , Pré-Escolar , Cloranfenicol O-Acetiltransferase/genética , Aberrações Cromossômicas , Síndrome de Cockayne/fisiopatologia , Dano ao DNA/genética , Reparo do DNA/genética , Síndrome de Down/genética , Síndrome de Down/fisiopatologia , Feminino , Fibroblastos/fisiologia , Humanos , Lactente , Linfócitos/fisiologia , Masculino , Micronúcleos com Defeito Cromossômico , Pessoa de Meia-Idade , Transfecção , Síndrome de Werner/fisiopatologia
15.
Eur J Biochem ; 198(2): 399-404, 1991 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-1828229

RESUMO

Using cDNA clones H-19 and H-46, we have shown previously that three different mRNA species (4.3 kb, 1.8 kb and 1.4 kb) for complement factor H are expressed constitutively in human liver. Here we report data suggesting that the expression of these different factor-H mRNA species is regulated by tissue-specific control mechanisms. Total RNA and poly(A)-enriched RNA from various human tissues (heart, lung, temporal cortex, kidney, spleen, bone marrow and muscle) various cell lines (HepG2, HepG3, HepG4, Hep3B, H-4, Jurkat, Molt4, H-9, KHos24Os, A-431, U937, Mono Mac 6 and Raji) and from primary cultures of peripheral blood monocytes, fibroblasts and human umbilical vein endothelial cells (HUVEC) were investigated for the expression of factor-H mRNA. In RNA preparations from extrahepatic tissue, factor-H mRNA was only detected in biopsies from the lung. Using 20 micrograms total RNA isolated from all 13 cell lines it was not possible to detect any factor-H mRNA, while mRNA for factor H was expressed in monocytes, HUVEC and fibroblasts. When expressed in extrahepatic tissues, only the 4.3-kb and the 1.8-kb mRNA species were detected, while the 1.4-kb mRNA is expressed abundantly in liver. Interferon-gamma did not induce the expression of factor-H mRNA in any of the cell lines tested. On the other hand, tumour necrosis factor-alpha induced the expression of the 4.3-kb mRNA species in U937 cells. In HUVEC and fibroblasts the relative quantities of the 4.3-kb and the 1.8-kb mRNA species and the regulatory effects of interferon-gamma, interleukin-1, dexamethasone and retinoic acid on their expression showed significant tissue specificity.


Assuntos
Proteínas Inativadoras do Complemento C3b/genética , RNA Mensageiro/genética , Northern Blotting , Linhagem Celular , Fator H do Complemento , Sondas de DNA , Dexametasona/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Expressão Gênica/efeitos dos fármacos , Humanos , Interferon gama/farmacologia , Interleucina-1/farmacologia , Monócitos/fisiologia , Especificidade de Órgãos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/isolamento & purificação , Proteínas Recombinantes/farmacologia , Tretinoína/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
16.
Hum Genet ; 83(4): 339-46, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2478446

RESUMO

We present clinical and biochemical data from three patients with severe Cockayne syndrome (CS) of very early onset. Unlike in classic CS, signs became evident in the first weeks of life and led to unusually early death. Fibroblasts from two of the patients showed a complete defect of the repair of UV-induced thymine dimer lesions. They were unable to remove thymine dimer lesions from their DNA, had a severe reduction of the RNA synthesis rates after UV irradiation, and showed no reactivation of an UV-inactivated indicator gene and no DNA recondensation after UV irradiation. DNA repair investigated in these two fibroblast cell strains resembled that of xeroderma pigmentosum cells of complementation group A. In contrast, fibroblasts from the third patient showed the same in vitro repair characteristics as classic CS cells.


Assuntos
Síndrome de Cockayne/genética , Reparo do DNA , Nanismo/genética , Dímeros de Pirimidina , Sobrevivência Celular , Células Cultivadas , Centrifugação , Cloranfenicol O-Acetiltransferase/genética , Cromatina , Ciclobutanos/metabolismo , Reparo do DNA/efeitos da radiação , Feminino , Fibroblastos/citologia , Expressão Gênica , Humanos , Lactente , Recém-Nascido , Masculino , RNA/biossíntese , Transfecção , Raios Ultravioleta
17.
Eur J Cell Biol ; 48(1): 79-87, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2526018

RESUMO

Trisomy 21 (Down's syndrome, DS) is the most frequent chromosomal aberration. Triplication of a small region of chromosome 21, the fragment 21q22 is sufficient to cause the DS phenotype including immunodeficiency, premature aging, neurodegenerations, mental retardation and an increased risk of leukemia. Chromosomal aberrations caused by X-ray irradiation were observed in DS lymphocytes and DS fibroblasts, but the correlation to cell death or repair deficiency was not clear. We approached this problem and report here on a profound X-ray repair deficiency of DS cells. With a colorimetric viability assay we observed an UV sensitivity of DS fibroblasts at doses beyond 14 Jm-2 but no significant X-ray sensitivity. By the nucleoid sedimentation technique, a deficient restoration of nucleoids in DS cells after X-ray irradiation was demonstrated. The same features apply for cells, which contain an overexpressed Cu/Zn-superoxide dismutase (SOD-1) gene. Radiation sensitivity of DS cells and SOD-1 overexpressing cells resemble those of ataxia telangiectasia (AT) fibroblasts. Additionally, DS and AT cells exert lack of inhibition of DNA synthesis after X-ray irradiation.


Assuntos
Síndrome de Down/patologia , Fibroblastos/efeitos da radiação , Superóxido Dismutase/genética , Linhagem Celular , Células Cultivadas , Cobre/metabolismo , Síndrome de Down/etiologia , Síndrome de Down/genética , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Superóxido Dismutase/metabolismo , Superóxido Dismutase/efeitos da radiação , Transfecção/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Raios X/efeitos adversos , Zinco/metabolismo
18.
Eur J Cell Biol ; 41(2): 352-5, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3758088

RESUMO

Fibroblasts from patients with Cockayne Syndrome (CS) are hypersensitive to UV light. DNA repair was analyzed in these cells by sedimentation behaviour of DNA nucleoids in sucrose gradients and compared to normal control cells. The initiation of repair, the incision of the DNA strand next to the UV lesion appeared to be normal. The rejoining of DNA stretches, however, is retarded in CS cells. DNA repair synthesis of UV damages was measured by autoradiography of [14C]thymidine incorporation into resting cells. Up to 4 h the DNA repair synthesis was comparable with normal cells. From 4 to 7 h the incorporation of radioactive precursors declined in CS cells. Besides a defective DNA polymerase this could be due to accelerated excorporation of radioactive nucleotides as a consequence of delayed ligation. In ligation the enzyme itself could be affected as well as its activation by ADP-ribosylation. Nicotine adenine dinucleotide (NAD+) is needed for the ADP ribosylation process. The cellular NAD+ content, however, was found to be the same in normal and in CS fibroblasts. Increase of the extracellular NAD+ supply accelerated the rejoining of UV damaged DNA in CS cells.


Assuntos
Síndrome de Cockayne/genética , Reparo do DNA , Nanismo/genética , Linhagem Celular , Síndrome de Cockayne/metabolismo , DNA/efeitos da radiação , Replicação do DNA/efeitos da radiação , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Pele/metabolismo , Raios Ultravioleta
19.
Eur J Biochem ; 140(1): 183-9, 1984 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-6368231

RESUMO

alpha Factor specifically inhibits the synthesis of N-glycosylated proteins in Saccharomyces cerevisiae mating type a cells but not in alpha cells or in a/alpha diploids. a Factor has the same effect of alpha cells. The synthesis of O-glycosylated proteins is not inhibited. Although the mating pheromones act like a 'physiological tunicamycin', the mechanism of inhibition is different: not the glycosylation of proteins as such but rather the synthesis of those proteins destined to be N-glycosylated is inhibited. Thus none of a number of glycosylating enzymes tested in vitro is reduced in activity in alpha-factor-treated cells. The synthesis of the glycoprotein carboxypeptidase Y, on the other hand, is strongly inhibited by tunicamycin as well as by alpha factor; but only in the former case did carbohydrate-free protein accumulate in the cells. alpha Factor causes maximal inhibition of glycoprotein formation after as little as 30 min, long before all cells in the population are arrested in G1; moreover, release from this inhibition precedes the increase in budding index (resumption of cell division). It is postulated, therefore, that N-glycosylated proteins are required for the G1/S-phase transition in the yeast cell cycle. This is supported by previous reports that first cycle arrest in G1 occurs when (a) tunicamycin is added to growing cultures, and (b) a temperature-sensitive N-glycosylation mutant is shifted to its restrictive temperature.


Assuntos
Proteínas Fúngicas/biossíntese , Glicoproteínas/biossíntese , Peptídeos/fisiologia , Feromônios/fisiologia , Saccharomyces cerevisiae/metabolismo , Animais , Carboxipeptidases/metabolismo , Catepsina A , Fenômenos Químicos , Precipitação Química , Química , Hexosiltransferases/metabolismo , Imunoquímica , Fator de Acasalamento , Proteínas de Saccharomyces cerevisiae
20.
Philos Trans R Soc Lond B Biol Sci ; 300(1099): 185-94, 1982 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-6131458

RESUMO

The pathways for protein N- and O-glycosylation in yeast cells are summarized. Evidence is presented that the terminal glucosyl residues of the dolichyl-PP-oligosaccharide intermediate are responsible for decreasing the Km for the peptide to be N-glycosylated. A liposomal model system is introduced that allows the study of a dolichyl phosphate (Dol-P) dependent transmembrane transport of mannosyl residues. The results obtained so far suggest that the mannosylation of Dol-P and the transmembrane translocation of Dol-P-Man are catalysed by the enzyme more or less simultaneously. However, only about 8-10% of the enzyme molecules incorporated into the liposomes seem to carry out the 'coupled' reaction. The glycosylation of carboxypeptidase Y is not required for this protein to reach the vacuole, its target organelle. In the presence of low concentrations of tunicamycin, however, yeast cells do stop growth. This does not seem to be due to the inhibition of secretion of glycoproteins like external invertase. It is postulated that protein glycosylation is crucial for a cell cycle event during the G1 phase.


Assuntos
Fosfatos de Dolicol/fisiologia , Proteínas Fúngicas/biossíntese , Glicoproteínas/biossíntese , Fosfatos de Poli-Isoprenil/fisiologia , Asparagina , Transporte Biológico , Retículo Endoplasmático/fisiologia , Lipossomos , Manose/metabolismo , Oligossacarídeos/biossíntese , Serina , Treonina
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