Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 107
Filtrar
1.
Clin Exp Dermatol ; 37(4): 425-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22299671

RESUMEN

An increased level of circulating nuclear antigens caused by apoptosis is thought to be responsible for the production of autoantibodies in lupus erythematosus (LE). The presentation of these antigens to immunologically competent cells may trigger systemic autoimmunity. The influence of a functional single-nucleotide polymorphism at position -670 in the promoter of the apoptosis gene FAS on susceptibility to autoimmune diseases including systemic LE has been a controversial subject. Although it has not yet been possible to assign any particular allele or genotype to the control of FAS expression, this polymorphism has been described to be associated with several autoimmune diseases including LE. When we compared the FAS -670 A/G genotypes of 107 German patients with LE and those of 96 healthy controls, we found a trend for association between LE and the homozygous A genotype in the patient group. This finding suggests that apoptosis may contribute to development of autoimmune reactions and that FAS function might be relevant for LE.


Asunto(s)
Predisposición Genética a la Enfermedad , Lupus Eritematoso Sistémico/genética , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/genética , Receptor fas/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad
2.
J Exp Med ; 173(1): 209-19, 1991 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-1670638

RESUMEN

Since a dysregulated synthesis of tumor necrosis factor alpha (TNF-alpha) may be involved in the pathogenesis of autoimmune diseases, it was of interest to precisely locate the recently reported NcoI restriction fragment length polymorphism (RFLP) of the TNF-alpha region. However, by mapping of 56.8 kb of overlapping cosmid clones and direct sequencing, we could localize the polymorphic NcoI restriction site within the first intron of the TNF-beta gene and not in the TNF-alpha gene. To study whether regulatory mechanisms are affected by this polymorphism, we analyzed the TNF-alpha/TNF-beta production of phytohemagglutinin-stimulated peripheral blood mononuclear cells of individuals homozygous for the TNF-beta NcoI RFLP by ELISA and concomitant Northern blot analysis. On days 2-4 after stimulation with mitogen, the TNFB*1 allele corresponding to a 5.3-kb NcoI fragment presented with a significantly higher TNF-beta response. A mRNA analysis demonstrated that higher protein levels of TNF-beta correlate also with increased amounts of TNF-beta transcripts. No allelic association was found in respect to TNF-alpha production. To further investigate a possible allelic influence on transcription, we determined the DNA sequence of 2 kb of the 5' portion of our cloned TNFB*2 allele and compared it with the available TNF-beta sequences. By computer-aided recognition motif search of DNA binding factors, we report putative binding sites conserved between mouse and man in the 5' flanking region as well as in intron 1 of the TNF-beta gene, found also in other cytokine promoter sequences. In addition, by polymerase chain reaction amplification and sequencing of 740 bp of the 5' part of TNF-beta of individuals typed homozygously for the NcoI RFLP, we could show that amino acid position 26 is conserved as asparagine in the TNFB*1 and as threonine in the TNFB*2 sequence. A previously reported, EcoRI RFLP in the 3' untranslated region of TNF-beta does not segregate with either of the two alleles. Thus, four TNFB alleles can be defined at the DNA level.


Asunto(s)
Linfotoxina-alfa/genética , Alelos , Secuencia de Aminoácidos , Secuencia de Bases , Desoxirribonucleasa EcoRI , Desoxirribonucleasas de Localización Especificada Tipo II , Regulación de la Expresión Génica/genética , Humanos , Intrones/genética , Activación de Linfocitos/efectos de los fármacos , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Linfotoxina-alfa/biosíntesis , Datos de Secuencia Molecular , Fitohemaglutininas/farmacología , Polimorfismo de Longitud del Fragmento de Restricción , Regiones Promotoras Genéticas/genética , Mapeo Restrictivo , Factor de Necrosis Tumoral alfa/genética
3.
Br J Dermatol ; 162(1): 64-73, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19712116

RESUMEN

Background Lupus erythematosus tumidus (LET) is a rare disease which was first described in 1909 but has not always been considered as a separate entity of cutaneous lupus erythematosus (CLE) in the international literature. Objectives To compare characteristic features of different subtypes of CLE and to analyse whether LET can be distinguished as a separate entity in the classification system of the disease. Methods The study involved 44 patients with CLE, including 24 patients with LET, 12 with discoid lupus erythematosus (DLE) and eight with subacute CLE (SCLE), from two centres in Germany. A core set questionnaire and an SPSS database were designed to enable a consistent statistical analysis. Results Location of skin lesions did not differ significantly between the CLE subtypes; however, the activity score was significantly lower in LET than in DLE (P < 0.01), and the damage score was significantly lower in LET than in SCLE (P < 0.01) and DLE (P < 0.01). Photosensitivity and antinuclear antibodies were confirmed to be different in LET compared with SCLE and DLE but without statistical significance. Moreover, histological analysis of skin biopsy specimens showed that abundant mucin deposition is significantly more present in LET compared with SCLE (P < 0.01) and DLE (P < 0.01) while prominent interface dermatitis and alteration of hair follicles were absent in LET. Conclusions Several significant differences were found between LET and other subtypes of CLE with regard to clinical, histological and laboratory parameters. These data strongly indicate that LET should be defined as a separate entity in the classification of CLE.


Asunto(s)
Lupus Eritematoso Cutáneo/clasificación , Adulto , Edad de Inicio , Anciano , Anticuerpos Antinucleares/análisis , Femenino , Alemania , Humanos , Lupus Eritematoso Cutáneo/inmunología , Lupus Eritematoso Cutáneo/patología , Lupus Eritematoso Discoide/clasificación , Lupus Eritematoso Discoide/inmunología , Lupus Eritematoso Discoide/patología , Masculino , Persona de Mediana Edad , Mucinas/análisis , Trastornos por Fotosensibilidad/etiología , Adulto Joven
4.
Tissue Antigens ; 74(4): 354-6, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19775376

RESUMEN

In this paper, we characterize the novel human leucocyte antigen (HLA)-DPB1*2402 allele that we found in a patient suffering from acne vulgaris. In comparison to the closest related allele DPB1*0401, HLA-DPB1*2402 has a single nucleotide exchange at position 115 (202), T replaces G. In consequence, codon 39 (68) TAC encodes for tyrosine in the novel allele instead of aspartic acid 39 (68) GAC in DPB1*0401.


Asunto(s)
Acné Vulgar/genética , Antígenos HLA-DP/genética , Análisis de Secuencia de ADN , Acné Vulgar/sangre , Alelos , Secuencia de Bases , Antígenos HLA-DP/sangre , Cadenas beta de HLA-DP , Prueba de Histocompatibilidad , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Homología de Secuencia de Ácido Nucleico
5.
Clin Exp Dermatol ; 34(8): 898-903, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19456767

RESUMEN

BACKGROUND: Autoimmune bullous disorders of the pemphigus group are characterized by autoantibodies targeting desmoglein (Dsg)1, Dsg3 and Dsg4 and occasionally, desmocollin (Dsc)1, Dsc2 and Dsc3. Both Dsg and Dsc are components of desmosomal adhesion complexes. AIM: To investigate the presence of IgG and IgA autoantibodies against Dsc1, Dsc2 and Dsc3 in a cohort of patients with bullous disorders. METHODS: IgG and IgA autoantibodies against Dsc1, Dsc2 and Dsc3 were investigated by ELISA and immunoblotting analysis in a cohort of European patients with pemphigus vulgaris (PV; n = 74), IgA pemphigus (n = 3), paraneoplastic pemphigus (PNP; n = 3) and two cases of atypical pemphigus (n = 2). RESULTS: Of the two cases with atypical pemphigus, one showed IgA reactivity against Dsc1 and Dsc3 and weak reactivity against Dsc2, and the other showed both IgG and IgA reactivity against Dsc1. One patient with IgA pemphigus had IgA autoantibodies against Dsc1, Dsc2 and Dsg1, and one patient with PNP had IgG reactivity against with Dsc3. In contrast, all the PV sera showed IgG reactivity against Dsg3 but not against Dsc1-3. Thus, IgG and IgA reactivity against Dsc was restricted to cases of PNP, IgA pemphigus and atypical pemphigus. CONCLUSIONS: These findings support the concept that desmocollins are not important autoantigens in PV.


Asunto(s)
Desmocolinas/inmunología , Inmunoglobulina A/análisis , Inmunoglobulina G/análisis , Pénfigo/inmunología , Autoanticuerpos/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Población Blanca
6.
Skin Res Technol ; 15(4): 476-81, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19832961

RESUMEN

BACKGROUND: New techniques for diagnostics and therapy in dermatology are becoming increasingly non-invasive, among which confocal laser-scanning microscopy (CLSM) is the most prevalent. It allows visualization of cellular structures of the skin up to a depth of 300 microm in vivo. Until now, most studies have been conducted on pathologically altered skin, mostly oncologic lesions. We now present a detailed analysis of capillaries located in the upper dermal papillae. METHODS: Multiple measurements were performed on the dorsal and ventral surface of the right forearm of 30 healthy volunteers (22-88 years) under standard conditions (room temperature, body position, time of day). Images were obtained with the Vivascope 1500 (Lucid) under standard settings and analyzed using the freeware ImageJ with a customwritten macro plugin. The following parameters of the capillaries in vivo were measured: area, perimeter, circularity and maximum diameter. RESULTS: Statistical analysis showed that all four parameters were constant within a narrow range, regardless of the body site, sex and age. In this physiological study, we can clearly demonstrate that by confocal laser-scanning capillaroscopy (CLSC), it is possible to visualize and measure skin capillaries at the extremities in a reproducible manner. CONCLUSION: This new approach offers a considerable advantage compared with nailfold capillaroscopy, which can only be performed at the proximal nail segment, and over histological analysis, which can be hampered by fixation artifacts resulting in altered size and shape of the vessels to be analyzed. CLSC could allow for precise analysis of in vivo skin vasculature in systemic and proliferative diseases of the skin.


Asunto(s)
Dermis/irrigación sanguínea , Angioscopía Microscópica/métodos , Microscopía Confocal/métodos , Psoriasis/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Dermis/patología , Femenino , Antebrazo , Humanos , Masculino , Angioscopía Microscópica/normas , Microscopía Confocal/normas , Persona de Mediana Edad , Psoriasis/patología , Reproducibilidad de los Resultados , Caracteres Sexuales , Adulto Joven
7.
Arch Dermatol Res ; 299(3): 163-4, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17457599

RESUMEN

Bullous pemphigoid (BP) is mediated by autoantibodies directed against molecules of the basement membrane zone. The biological function of antibodies involves binding to Fc-receptors expressed on human leucocytes. Recent studies suggested that a functional single-nucleotide-polymorphism of the Fcgamma-receptor IIIa (FcgammaRIIIa = CD16) at nucleotide 559 might predispose to the development of antibody-associated autoimmune disorders. This allelic difference affects the level of receptor affinity by predicting either a phenylalanine (F 158, low-affinity) or valine (V 158, high-affinity). We investigated if inherited frequencies of the high- and low-affinity FcgammaRIIIa polymorphism differed between patients with BP and healthy subjects. Genomic DNA from peripheral white blood cells was analyzed regarding FcgammaRIIIa polymorphism at nucleotide 559 by an established polymerase chain reaction. Sixty-seven Caucasian patients with BP and 88 healthy controls were included into the study. There was no significant difference in the distribution of the homozygous high-affinity FcgammaRIIIa-allotype (V/V) between BP-patients (14.9%) and healthy control subjects (20.5%). In contrast, 58.2% of the BP-patients were homozygous for the low-affinity FcgammaRIIIa-allotype (F/F), compared to 28.4% of the healthy controls (P = 0.001, OR 3.51). The frequencies of the polymorphism in the control group were in range of formerly published frequencies for healthy Caucasian subjects. Thus, the FcgammaRIIIa (158 F/V) polymorphism may modulate the susceptibility to acquire BP.


Asunto(s)
Penfigoide Ampolloso/genética , Polimorfismo de Nucleótido Simple/genética , Receptores de IgG/genética , Estudios de Casos y Controles , ADN/genética , Predisposición Genética a la Enfermedad , Homocigoto , Humanos
8.
Cancer Res ; 55(11): 2373-9, 1995 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-7757989

RESUMEN

Inducibility and regulation of the pleiotropic cytokine interleukin 6 (IL-6) upon photodynamic therapy (PDT) was studied in the epithelial cell line HeLa. Photofrin-mediated photosensitization resulted in a rapid and dose-dependent induction of IL-6 mRNA production. Maximal levels were reached after 4 h and had decreased to baseline levels after 24 h. This photochemical induction of IL-6 transcription was followed by a strong secretion of IL-6 protein. In comparison to stimulation by 12-O-tetradecanoylphorbol-13-acetate, the kinetics of IL-6 mRNA and protein synthesis after PDT were delayed, although the maximal amounts of secreted IL-6 protein were comparable. As compared to UV irradiation, on the other hand, PDT-induced IL-6 protein levels were 2- to 10-fold higher and were detectable 4 h earlier. Several potentially relevant regulatory DNA elements of the IL-6 promoter were analyzed by gel retardation assays for PDT-induced protein binding. Interestingly, increased AP-1 DNA binding was detected only at the distal AP-1-specific motif and not at the proximal site, differing in 1 bp. Binding of c-Fos-containing AP-1 heterodimers to the specific motif was up-regulated 30 min after PDT, reaching maximal activity at 4 h. This PDT-induced AP-1 activation was independent from protein kinase C activity. Photosensitization did not induce increased binding at the well-characterized NF-kappa B element, nor at the multiple cytokine- and second messenger-responsive element of the IL-6 promoter. By analyzing the molecular mechanisms of IL-6 up-regulation upon PDT, we provide evidence for regulatory differences compared to UV light, ionizing irradiation, or stimulation by phorbol ester. Furthermore, this study suggests that the "proinflammatory" cytokine IL-6 might be involved in the inflammatory reaction and subsequent immunological antitumor responses.


Asunto(s)
ADN de Neoplasias/efectos de los fármacos , ADN de Neoplasias/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Fotorradiación con Hematoporfirina , Interleucina-6/biosíntesis , Interleucina-6/genética , FN-kappa B/efectos de los fármacos , FN-kappa B/metabolismo , Factor de Transcripción AP-1/efectos de los fármacos , Factor de Transcripción AP-1/metabolismo , Secuencia de Bases , Sitios de Unión , ADN de Neoplasias/efectos de la radiación , Expresión Génica/efectos de los fármacos , Expresión Génica/efectos de la radiación , Células HeLa , Derivado de la Hematoporfirina/farmacología , Humanos , Interleucina-6/metabolismo , Datos de Secuencia Molecular , FN-kappa B/efectos de la radiación , ARN Mensajero/genética , Factor de Transcripción AP-1/efectos de la radiación , Rayos Ultravioleta
9.
Leukemia ; 14(4): 706-11, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10764158

RESUMEN

We have studied the frequency of p53 mutations in genomic DNA extracted from peripheral blood or the spleen of 61 patients with hairy cell leukemia using PCR-SSCP and automated cycle sequencing. We identified exon 5-8 mutations in 17 cases, corresponding to a frequency of 28%. In four cases, mutations were localized in exon 5; one patient with atypical HCL had a mutation in exon 6 at the 3' boundary; five cases showed mutations in exon 7, while exon 8 was found to be mutated in seven cases. The mutations found could be divided into three major categories: structural (n=9), inactivating (n= 6), and neutral (n= 2) mutations. None of the three transitions found occurred at CpG dinucleotides. The rate of p53 mutations found in this large cohort of HCL patients is unexpectedly high as in other non-Hodgkin lymphomas p53 mutations predict for poor treatment outcome. The character of the mutations we have found is entirely different from that described in other hematologic malignancies.


Asunto(s)
Genes p53 , Leucemia de Células Pilosas/genética , Mutación , Adulto , Anciano , Sustitución de Aminoácidos , Ciclo Celular , Codón , Estudios de Cohortes , Islas de CpG , Análisis Mutacional de ADN , ADN de Neoplasias/sangre , ADN de Neoplasias/genética , Femenino , Humanos , Leucemia de Células Pilosas/mortalidad , Leucemia de Células Pilosas/patología , Linfoma no Hodgkin/genética , Linfoma no Hodgkin/mortalidad , Masculino , Persona de Mediana Edad , Mutación Puntual , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Pronóstico , Eliminación de Secuencia , Bazo/química
10.
Arch Intern Med ; 141(13): 1797-1801, 1981 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7316626

RESUMEN

Cholestatic jaundice developed in four patients after the administration of prajmalium bitartrate. The clinical, histologic, ultrastructural, and immunologic findings were determined. In all patients, the clinical and morphologic features indicated idiosyncrasy. Two antibodies distributed in a granular pattern along the bile canaliculi were detected by immunofluorescence in all patients. In one patient, autoimmune markers were found in the serum, and in two instances, the migration-inhibition factor assay against the offending drug was found to be positive. The data support the concept that immunologic processes may participate in the production of the cholestatic syndrome.


Asunto(s)
Ajmalina/análogos & derivados , Colestasis/inducido químicamente , Prajmalina/efectos adversos , Anciano , Anticuerpos/análisis , Reacciones Antígeno-Anticuerpo , Colestasis/inmunología , Colestasis/patología , Proteínas del Sistema Complemento/análisis , Femenino , Humanos , Inmunoglobulinas/análisis , Hígado/inmunología , Hígado/patología , Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Prajmalina/inmunología
11.
Immunobiology ; 182(1): 79-87, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1983003

RESUMEN

The ICAM-1 glycoprotein, one of the major cellular adhesion molecules, exhibits a diverse and highly regulated tissue distribution. To better understand the regulatory mechanisms underlying its particular expression pattern, we have cloned the ICAM-1 gene from human leukocyte libraries. By hybridization with various DNA probes derived from different regions of the ICAM-1 cDNA, several clones were identified and isolated. Clone HWB 3R1, containing a 15kb DNA insert, was selected for further characterization. The HWB 3R1 clone hybridized with probes corresponding to the 3' as well as the 5' region of the ICAM-1 cDNA and gave rise to ICAM-1 expression after transfection into the ICAM-1 deficient MJP17 melanoma cell line. The identity of the expressed ICAM-1 was verified by reaction with five different monoclonal antibodies specific for ICAM-1. Sequence analysis of about 1.2kb of DNA around the ATG start codon revealed putative binding sites for various transcription factors situated in the 5' untranslated region as well as within the first intron. These include SP-1, AP-1 and NF-kB binding sites as well as interferon and retinoic acid responsive elements.


Asunto(s)
Moléculas de Adhesión Celular/genética , Secuencias Reguladoras de Ácidos Nucleicos , Secuencia de Aminoácidos , Anticuerpos Monoclonales , Secuencia de Bases , Sitios de Unión , Southern Blotting , Clonación Molecular , Secuencia de Consenso/genética , Sondas de ADN , Regulación de la Expresión Génica , Humanos , Molécula 1 de Adhesión Intercelular , Intrones , Datos de Secuencia Molecular , Regiones Promotoras Genéticas/genética , Factores de Transcripción/metabolismo , Transfección , Células Tumorales Cultivadas
12.
Radiat Res ; 148(6): 531-42, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9399698

RESUMEN

Eosinophilia is often observed in patients with parasitic infections and atopic diseases like allergic asthma and atopic dermatitis. Additionally, it is a typical feature of the inflammatory reaction after therapeutic and accidental exposure to ionizing radiation. This uniquely specific phenomenon regulated by the cytokine interleukin 5 (IL-5) suggests specific control for IL5 gene expression. In this study, we generated promoter-CAT constructs containing different human IL-5 promoter regions spanning from positions -507 to +43. Transfection experiments in Jurkat T cells revealed that the promoter sequence from -57 to +43 was required for constitutive and inducible IL-5 promoter activity. Low baseline CAT activity could be enhanced by treatment with phenylmercuric acetate (PMA) or the combination of PMA and calcium ionophore. The promoter region between positions -97 and +43 showed responsiveness to low-dose X rays. Electrophoretic mobility shift assays demonstrated that the region from -117 to -97 was responsive to irradiation. Transcription factors specifically bound to this sequence showed a dose-dependent response to single doses of X rays between 1 and 8 Gy. Competition analysis indicated that the protein-DNA complexes at this region were related to the nuclear factor of activated T cells (NF-AT). Further confirmation was obtained by the addition of specific antibodies into protein-DNA reactions. For the first time, we have demonstrated that specific DNA binding of NF-ATp at the promoter region from -117 to -97 is involved in transcriptional regulation of the human IL5 gene in response to ionizing radiation.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Interleucina-5/genética , Proteínas Nucleares , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de la radiación , ADN/metabolismo , Humanos , Células Jurkat , Factores de Transcripción NFATC , Regiones Promotoras Genéticas , Acetato de Tetradecanoilforbol/farmacología
13.
Rheum Dis Clin North Am ; 18(1): 177-86, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1348586

RESUMEN

HLA antigens have been shown to be associated with several immunoinflammatory diseases. The mechanisms by which these antigens confer susceptibility to disease continue to be of major interest. Rapid progress has been made in the elucidation of the structure and function of class I and II MHC molecules, and several genes located within the HLA complex have been identified which are potentially involved in immunologic processes. Because of the HLA localization of the TNF-alpha and -beta genes and the biologic activities of the gene products, recent investigation has focused on a possible role of polymorphic TNF genes in the pathogenesis of HLA-associated diseases. Allelic variations have only been detected in the TNF-beta gene. No evidence has been found so far that a particular TNF-beta allele contributes significantly in the susceptibility to the diseases studied. Although it has been postulated that the TNF beta*2 allele contributes to susceptibility to IDDM in HLA-DR3, 4 heterozygous individuals, a larger group of HLA-typed patients and controls is needed to provide more conclusive evidence for this hypothesis. The increasing number of genes of unknown function encoded by the class III region leaves the possibility that the observed HLA associations in some diseases may be related to the presence of these genes. In AS, the lack of association with the TNF-beta alleles furthermore supports the function of the HLA-B27 molecule in the disease and underlines the improbability that HLA-B27 is merely a marker for a closely linked susceptibility gene.


Asunto(s)
Polimorfismo Genético , Enfermedades Reumáticas/genética , Factor de Necrosis Tumoral alfa/genética , Citocinas/biosíntesis , Antígenos HLA/genética , Humanos , Polimorfismo de Longitud del Fragmento de Restricción , Factores de Riesgo , Espondilitis Anquilosante/genética
14.
Am J Trop Med Hyg ; 35(6): 1110-6, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3789266

RESUMEN

Methylbenzethonium chloride (MBCl) decreased the growth of Leishmania major promastigotes and amastigotes in vitro. This decrease occurred during 4 days of exposure to the drug at concentrations of 0.1 to 2.5 micrograms ml-1. MBCl at 2 micrograms ml-1 killed almost 100% of the free living promastigotes and 87% of amastigotes within 4 days of treatment. Electron microscopy studies showed marked swelling of mitochondria in treated parasites. A possible additional effect on the parasite surface membrane is discussed.


Asunto(s)
Bencetonio/farmacología , Leishmania tropica/efectos de los fármacos , Compuestos de Amonio Cuaternario/farmacología , Bencetonio/análogos & derivados , Relación Dosis-Respuesta a Droga , Leishmania tropica/ultraestructura , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica , Mitocondrias/efectos de los fármacos , Mitocondrias/ultraestructura , Dilatación Mitocondrial/efectos de los fármacos
15.
Arch Dermatol ; 133(6): 767-71, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9197833

RESUMEN

OBJECTIVES: To update information on endogenous retroviral sequences and discuss their role in systemic autoimmune disease. DATA SOURCES: Articles retrieved after MEDLINE search and personal communications and cooperation with the Institute of Virology. DATA SYNTHESIS: There are 2 modes of pathogenetic mechanisms through which endogenous retroviral sequences could cause systemic autoimmune disease: expression of endogenous retroviral gene products sharing antigenic determinants with cellular proteins; and activation or destruction of cellular genes as a consequence of insertional mutagenesis. Both mechanisms have been demonstrated in vitro and in vivo in animal models. CONCLUSION: Investigations on endogenous retroviral sequences in humans may offer new insights into the pathogenesis of autoimmune disease.


Asunto(s)
Enfermedades Autoinmunes/virología , Retroviridae/genética , Genes Virales/genética , Humanos
16.
J Dent Res ; 82(4): 262-6, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12651928

RESUMEN

The integrity of fiber-reinforced composite (FRC) prostheses is dependent, in part, on flexural rigidity. The object of this study was to determine if the flexure behavior of uniform FRC beams with restrained or simply supported ends and various length/depth (L/d) aspect ratios could be more accurately modeled by correcting for shear. Experimental results were compared with three analytical models. All models were accurate at high L/d ratios, but the shear-corrected model was accurate to the lowest, more clinically relevant, L/d values. In this range, more than 40% of the beam deflection was due to shear.


Asunto(s)
Resinas Compuestas , Análisis del Estrés Dental , Dentadura Parcial Fija , Diseño de Dentadura , Elasticidad , Ensayo de Materiales , Docilidad , Resistencia al Corte
17.
Oncol Res ; 10(2): 69-74, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9666514

RESUMEN

Hypoxia leads to a cellular stress reaction and can induce transcription of immediate early genes, such as c-fos. We have generated a differential cDNA cloning strategy to isolate further hypoxia-induced genes. We report on the identification and characterization of a novel transcript (cDNA clone pSH16), which is inducible 12-fold in HeLa cells after 50 min of exposure to hypoxia. Sequence analysis revealed a hybrid transcript with high homology to the mammalian growth-related protein p23 mRNA fused to mitochondrial 16S rRNA. Complete homology was found for the coding region, whereas the 3'-untranslated part of the hypoxia-induced p23 sequence was elongated and carried an ATTTA box and a second consensus poly(A) signal in addition. The functional integrity of the pSH16 mRNA was verified by cell-free translation. Hypoxia induced the expression of both fusion partners, p23 and 16S rRNA, separately. In contrast to the hypoxia-induced expression in HeLa cells, we found constitutive high-level expression in breast and cervix tissue. No further upregulation of p23 transcripts was detectable in primary tumors of the breast and cervix. These data provide first evidence for a hypoxia-induced upregulation of the mammalian growth-related protein p23, which might be relevant for understanding of the physiology of hypoxic conditions in tumors.


Asunto(s)
Biomarcadores de Tumor , Hipoxia de la Célula/genética , ADN Complementario/química , Sustancias de Crecimiento/química , Proteínas de Neoplasias/química , Secuencia de Aminoácidos , Secuencia de Bases , ADN Complementario/aislamiento & purificación , Regulación de la Expresión Génica , Células HeLa , Humanos , Datos de Secuencia Molecular , ARN/química , ARN Mitocondrial , ARN Ribosómico 16S/química , Alineación de Secuencia , Proteína Tumoral Controlada Traslacionalmente 1
18.
Eur J Surg Oncol ; 14(1): 83-6, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2831104

RESUMEN

We describe a case of a malignant fibrous histiocytoma (MFH) arising in a scar. Previous reports have described this tumor associated with radiation, bone infarcts, foreign body reaction and in previous surgery sites. The present case emphasizes the correlation between chronic reparative reactions with external irritation and the appearance of this tumor.


Asunto(s)
Cicatriz/complicaciones , Histiocitoma Fibroso Benigno/etiología , Anciano , Ingle , Humanos , Masculino
19.
Gen Hosp Psychiatry ; 14(1): 56-60, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1730402

RESUMEN

A case is presented in which a patient who required treatment with electroconvulsive therapy had a history of being treated with pseudocholinesterase-inhibitor eye drops (echothiophate iodide) for glaucoma. As treatment with this antiglaucoma agent contraindicated the use of succinylcholine for a minimum of 10-14 days, the short-acting nondepolarizing agent atracurium was employed instead. The anesthetic management of this patient is described as a guide for clinicians facing similar clinical situations.


Asunto(s)
Atracurio/uso terapéutico , Trastorno Depresivo/terapia , Yoduro de Ecotiofato , Terapia Electroconvulsiva , Glaucoma/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Atracurio/farmacología , Butirilcolinesterasa/sangre , Contraindicaciones , Trastorno Depresivo/complicaciones , Yoduro de Ecotiofato/farmacología , Femenino , Glaucoma/sangre , Glaucoma/complicaciones , Humanos , Succinilcolina/farmacología
20.
Int J Radiat Biol ; 72(1): 33-43, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9246192

RESUMEN

The cutaneous radiation syndrome after therapeutic or accidental exposure of human skin to ionizing radiation (IR) is accompanied by inflammatory processes which are controlled partly by proinflammatory cytokines. Besides tumour necrosis factor (TNF)-alpha and interleukin (IL)1, the pluripotent cytokine IL-6 belongs to the key mediators of inflammation. So far, there are no reports about the regulation of IL-6 by IR in epidermal cells. As an in vitro model to study the effects of IR on IL-6 gene expression, we treated the human epithelial HeLa cell line with different single X-ray doses between 1 and 20 Gy. Twenty-four hours after irradiation the IL-6 secretion was dose-dependently enhanced as measured by ELISA. At the transcriptional level, a slight increase of IL-6 transcripts was already detectable 1 h after irradiation, with maximum levels at 2 h, and a decline to baseline levels between 8 and 24 h. Addition of the transcriptional inhibitor actinomycin D inhibited the inducibility of IL-6 mRNA by TPA and IR. As the IL-6 promoter contains multiple binding sites for activated glucocorticoid receptors within the 5' regulatory region, the potential modulation of IL-6 expression by the corticosteroids hydrocortisone, dexamethasone and mometasone furoate was included in our study to modify the radiation-induced stress response. All corticosteroids applied could efficiently downregulate TPA- or radiation-induced IL-6 expression on both gene expression and protein levels. Mometasone furoate, followed by dexamethasone, was found to be most effective at low concentrations (1 nM), whereas hydrocortisone had to be applied at about 100-fold higher concentrations to achieve comparable inhibition. This experimental model is aimed at understanding the molecular circuits following IR, and thus to provide a basis for the treatment of radiation effects in skin.


Asunto(s)
Corticoesteroides/farmacología , Interleucina-6/biosíntesis , Carcinógenos/farmacología , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/efectos de la radiación , Epitelio/efectos de los fármacos , Epitelio/metabolismo , Epitelio/efectos de la radiación , Células HeLa/metabolismo , Células HeLa/efectos de la radiación , Humanos , ARN Mensajero/biosíntesis , ARN Mensajero/metabolismo , ARN Mensajero/efectos de la radiación , Acetato de Tetradecanoilforbol/farmacología , Transcripción Genética/efectos de los fármacos , Transcripción Genética/efectos de la radiación , Regulación hacia Arriba/efectos de la radiación , Rayos X
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda