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1.
J Eur Acad Dermatol Venereol ; 34(12): 2717-2744, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33205485

RESUMEN

Atopic dermatitis (AD) is a highly pruritic, chronic inflammatory skin disease. The diagnosis is made using evaluated clinical criteria. Disease activity and burden are best measured with a composite score, assessing both objective and subjective symptoms, such as SCORing Atopic Dermatitis (SCORAD). AD management must take into account clinical and pathogenic variabilities, the patient's age and also target flare prevention. Basic therapy includes hydrating and barrier-stabilizing topical treatment universally applied, as well as avoiding specific and unspecific provocation factors. Visible skin lesions are treated with anti-inflammatory topical agents such as corticosteroids and calcineurin inhibitors (tacrolimus and pimecrolimus), which are preferred in sensitive locations. Topical tacrolimus and some mid-potency corticosteroids are proven agents for proactive therapy, which is defined as the long-term intermittent anti-inflammatory therapy of frequently relapsing skin areas. Systemic anti-inflammatory or immunosuppressive treatment is a rapidly changing field requiring monitoring. Oral corticosteroids have a largely unfavourable benefit-risk ratio. The IL-4R-blocker dupilumab is a safe, effective and licensed, but expensive, treatment option with potential ocular side-effects. Other biologicals targeting key pathways in the atopic immune response, as well as different Janus kinase inhibitors, are among emerging treatment options. Dysbalanced microbial colonization and infection may induce disease exacerbation and can justify additional antimicrobial treatment. Systemic antihistamines (H1R-blockers) only have limited effects on AD-related itch and eczema lesions. Adjuvant therapy includes UV irradiation, preferably narrowband UVB or UVA1. Coal tar may be useful for atopic hand and foot eczema. Dietary recommendations should be patient-specific, and elimination diets should only be advised in case of proven food allergy. Allergen-specific immunotherapy to aeroallergens may be useful in selected cases. Psychosomatic counselling is recommended to address stress-induced exacerbations. Efficacy-proven 'Eczema school' educational programmes and therapeutic patient education are recommended for both children and adults.


Asunto(s)
Dermatitis Atópica , Eccema , Adulto , Antiinflamatorios/uso terapéutico , Inhibidores de la Calcineurina/uso terapéutico , Niño , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/tratamiento farmacológico , Humanos , Prurito , Tacrolimus/uso terapéutico
2.
J Eur Acad Dermatol Venereol ; 33(9): 1644-1659, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31231864

RESUMEN

Atopic dermatitis (AD) is a common inflammatory skin disease that affects both children and adults, including a large number of adults of reproductive age. Several guidelines for the treatment of AD exist, yet specific recommendations for the treatment of pregnant or lactating women and for adults planning to have a child are often lacking. This position paper from the European Task force on Atopic Dermatitis (ETFAD) is based on up-to-date scientific literature on treating pregnant and lactating women as wells as adults with AD planning to have a child. It is based on the expert opinions of members of the ETFAD and on existing safety data on the proposed treatments, many of which are derived from patients with other inflammatory diseases or from transplantation medicine. For treating future parents, as well as pregnant and lactating women with AD, the use of topical treatments including moisturizers, topical corticosteroids, tacrolimus, antiseptics such as chlorhexidine, octenidine, potassium permanganate and sodium hypochlorite (bleach) is deemed to be safe. Ultraviolet (UV) therapy may also be used. Systemic treatment should be prescribed only after careful consideration. According to the opinion of the ETFAD, treatment should be restricted to systemic corticosteroids and cyclosporine A, and, in selected cases, azathioprine.


Asunto(s)
Dermatitis Atópica/terapia , Fármacos Dermatológicos/uso terapéutico , Lactancia , Atención Preconceptiva , Terapia Ultravioleta , Adulto , Comités Consultivos , Europa (Continente) , Femenino , Humanos , Masculino , Embarazo
3.
J Eur Acad Dermatol Venereol ; 30(5): 729-47, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27004560

RESUMEN

Atopic dermatitis (AD) is a clinically defined, highly pruritic, chronic inflammatory skin disease of children and adults. The diagnosis is made using evaluated clinical criteria. Disease activity is best measured with a composite score assessing both objective signs and subjective symptoms, such as SCORAD. The management of AD must consider the clinical and pathogenic variabilities of the disease and also target flare prevention. Basic therapy includes hydrating topical treatment, as well as avoidance of specific and unspecific provocation factors. Anti-inflammatory treatment of visible skin lesions is based on topical glucocorticosteroids and the topical calcineurin inhibitors tacrolimus and pimecrolimus. Topical calcineurin inhibitors are preferred in sensitive locations. Tacrolimus and mid-potent steroids are proven for proactive therapy, which is long-term intermittent anti-inflammatory therapy of the frequently relapsing skin areas. Systemic anti-inflammatory or immunosuppressive treatment is indicated for severe refractory cases. Biologicals targeting key mechanisms of the atopic immune response are promising emerging treatment options. Microbial colonization and superinfection may induce disease exacerbation and can justify additional antimicrobial treatment. Systemic antihistamines (H1R-blockers) may diminish pruritus, but do not have sufficient effect on lesions. Adjuvant therapy includes UV irradiation, preferably UVA1 or narrow-band UVB 311 nm. Dietary recommendations should be patient specific and elimination diets should only be advised in case of proven food allergy. Allergen-specific immunotherapy to aeroallergens may be useful in selected cases. Psychosomatic counselling is recommended to address stress-induced exacerbations. 'Eczema school' educational programmes have been proven to be helpful for children and adults.


Asunto(s)
Dermatitis Atópica/terapia , Adulto , Niño , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/radioterapia , Humanos
7.
Mult Scler ; 20(9): 1171-81, 2014 08.
Artículo en Inglés | MEDLINE | ID: mdl-24526664

RESUMEN

BACKGROUND AND OBJECTIVE: Interactions between TIRC7 (a novel seven-transmembrane receptor on activated lymphocytes) and its ligand HLA-DR might be involved in the inflammatory process in multiple sclerosis (MS). METHODS: Methods comprised immunohistochemistry and microscopy on archival MS autopsies, proliferation-, cytokine-, and surface-staining assays using peripheral blood lymphocytes (PBLs) from MS patients and an in vitro model. RESULTS: TIRC7 was expressed in brain-infiltrating lymphocytes and strongly correlated with disease activity in MS. TIRC7 expression was reduced in T cells and induced in B cells in PBLs obtained from MS patients. After ex vivo activation, T cell expression of TIRC7 was restored in patients with active MS disease. The interaction of TIRC7(+) T lymphocytes with cells expressing HLA-DR on their surface led to T cell proliferation and activation whereas an anti-TIRC7 mAb preventing interactions with its ligand inhibited proliferation and Th1 and Th17 cytokine expression in T cells obtained from MS patients and in myelin basic protein-specific T cell clone. CONCLUSION: Our findings suggest that TIRC7 is involved in inflammation in MS and anti-TIRC7 mAb can prevent immune activation via selective inhibition of Th1- and Th17-associated cytokine expression. This targeting approach may become a novel treatment option for MS.


Asunto(s)
Encéfalo/metabolismo , Antígenos HLA-DR/metabolismo , Esclerosis Múltiple/metabolismo , Células TH1/metabolismo , Células Th17/metabolismo , ATPasas de Translocación de Protón Vacuolares/metabolismo , Animales , Antiinflamatorios/farmacología , Anticuerpos Monoclonales/farmacología , Autopsia , Biomarcadores/sangre , Encéfalo/efectos de los fármacos , Encéfalo/inmunología , Encéfalo/patología , Estudios de Casos y Controles , Proliferación Celular , Células Cultivadas , Citocinas/metabolismo , Antígenos HLA-DR/genética , Antígenos HLA-DR/inmunología , Humanos , Mediadores de Inflamación/metabolismo , Activación de Linfocitos , Ratones , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/inmunología , Índice de Severidad de la Enfermedad , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células Th17/efectos de los fármacos , Células Th17/inmunología , Factores de Tiempo , Transfección , ATPasas de Translocación de Protón Vacuolares/antagonistas & inhibidores , ATPasas de Translocación de Protón Vacuolares/inmunología
8.
Allergy ; 66(8): 1114-21, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21414011

RESUMEN

BACKGROUND: Patient-oriented medicine is an emerging concept, encouraged by the World Health Organization, to greater involvement of the patient in the management of chronic diseases. The Patient-Oriented SCORing Atopic Dermatitis (PO-SCORAD) index is a self-assessment score allowing the patient to comprehensively evaluate the actual course of atopic dermatitis (AD), using subjective and objective criteria derived mainly from the SCORAD, a validated AD severity clinical assessment tool. OBJECTIVES: To validate the PO-SCORAD index in a large European population of patients exhibiting all forms of AD severity by assessing its correlation with the SCORAD index. PATIENTS/METHODS: Four hundred and seventy-one patients (185 adults, 286 children) consulting for AD in hospitals from 9 European countries were recruited. The investigators and the patients used the SCORAD and PO-SCORAD scales, respectively, to assess AD severity at inclusion (D0) and 28 ± 7 days later (D28). RESULTS: Patient-Oriented SCORing Atopic Dermatitis and SCORAD scores were significantly correlated at D0 [r = 0.67 (95% CI: 0.62; 0.72), P < 0.0001]. Consistency was confirmed at D28, with a stronger linear correlation between both scales [r = 0.79 (95% CI: 0.75; 0.83), P < 0.0001]. Absolute changes from baseline in SCORAD and PO-SCORAD scores were also significantly correlated [r= 0.71 (95% CI: 0.64; 0.76), P < 0.0001]. Although no specific intervention was investigated, AD improved over the study, with a decrease of PO-SCORAD and SCORAD scores from D0 to D28 by -19.19% and -24.39%, respectively. The consistency of the correlations was similar in the adult and children groups. CONCLUSIONS: This study validated the use of PO-SCORAD to self-assess AD severity and demonstrated its good correlation with SCORAD.


Asunto(s)
Dermatitis Atópica/diagnóstico , Autoevaluación (Psicología) , Índice de Severidad de la Enfermedad , Adolescente , Adulto , Niño , Preescolar , Europa (Continente) , Femenino , Humanos , Masculino , Pacientes , Estudios Prospectivos , Adulto Joven
9.
J Cell Biol ; 135(1): 253-67, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8858178

RESUMEN

Neural cell adhesion molecules of the immunoglobulin/fibronectin type III family on axons have been implicated in promotion of neurite outgrowth, fasciculation, and the mediation of specific cell adhesion. The present study demonstrates that two of these molecules on dorsal root ganglion neurons are associated with distinct protein kinases, axonin-1 with the src-related nonreceptor tyrosine kinase fyn and NgCAM with a casein kinase II-related activity and a serine/ threonine kinase related to S6 kinase. When neurites grew without contacts involving axonin-1 and NgCAM, strong fyn kinase activity was associated with axonin-1, whereas the NgCAM-associated kinase activities were low. Clustering of axonin-1 with NgCAM induced by the formation of cell-cell contacts correlated with a reduction of the axonin-1-associated fyn activity and an increased phosphorylation of NgCAM by the associated casein kinase II-related activity. Thus, axonin-1 and NgCAM trigger distinctive intracellular signals during in vitro differentiation depending on their state of association.


Asunto(s)
Moléculas de Adhesión Celular Neurona-Glia/metabolismo , Moléculas de Adhesión Celular Neuronal/metabolismo , Neuritas/fisiología , Transducción de Señal/fisiología , Animales , Quinasa de la Caseína II , Moléculas de Adhesión Celular Neurona-Glia/química , Moléculas de Adhesión Celular Neuronal/química , Comunicación Celular/fisiología , Diferenciación Celular , Células Cultivadas , Embrión de Pollo , Contactina 2 , Inhibidores Enzimáticos/farmacología , Ganglios Espinales/fisiología , Genisteína , Heparina/farmacología , Isoflavonas/farmacología , Peso Molecular , Oligonucleótidos Antisentido , Fosforilación , Fosfotirosina/análisis , Pruebas de Precipitina , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-fyn , Proteínas Quinasas S6 Ribosómicas
10.
J Cell Biol ; 135(6 Pt 1): 1593-607, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8978825

RESUMEN

The axonal surface glycoproteins neuronglia cell adhesion molecule (NgCAM) and axonin-1 promote cell-cell adhesion, neurite outgrowth and fasciculation, and are involved in growth cone guidance. A direct binding between NgCAM and axonin-1 has been demonstrated using isolated molecules conjugated to the surface of fluorescent microspheres. By expressing NgCAM and axonin-1 in myeloma cells and performing cell aggregation assays, we found that NgCAM and axonin-1 cannot bind when present on the surface of different cells. In contrast, the cocapping of axonin-1 upon antibody-induced capping of NgCAM on the surface of CV-1 cells coexpressing NgCAM and axonin-1 and the selective chemical cross-linking of the two molecules in low density cultures of dorsal root ganglia neurons indicated a specific and direct binding of axonin-1 and Ng-CAM in the plane of the same membrane. Suppression of the axonin-1 translation by antisense oligonucleotides prevented neurite outgrowth in dissociated dorsal root ganglia neurons cultured on an NgCAM substratum, indicating that neurite outgrowth on NgCAM substratum requires axonin-1. Based on these and previous results, which implicated NgCAM as the neuronal receptor involved in neurite outgrowth on NgCAM substratum, we concluded that neurite outgrowth on an NgCAM substratum depends on two essential interactions of growth cone NgCAM: a trans-interaction with substratum NgCAM and a cis-interaction with axonin-1 residing in the same growth cone membrane.


Asunto(s)
Moléculas de Adhesión Celular Neurona-Glia/fisiología , Moléculas de Adhesión Celular Neuronal/fisiología , Neuritas/fisiología , Secuencia de Aminoácidos , Animales , Anticuerpos/inmunología , Secuencia de Bases , Células COS , Moléculas de Adhesión Celular Neurona-Glia/química , Moléculas de Adhesión Celular Neuronal/química , Moléculas de Adhesión Celular Neuronal/inmunología , Agregación Celular , Línea Celular , Membrana Celular/química , Membrana Celular/fisiología , Embrión de Pollo , Contactina 2 , ADN , Dimerización , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Transcripción Genética , Células Tumorales Cultivadas
11.
J Cell Biol ; 143(6): 1673-90, 1998 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-9852159

RESUMEN

Neural cell adhesion molecules composed of immunoglobulin and fibronectin type III-like domains have been implicated in cell adhesion, neurite outgrowth, and fasciculation. Axonin-1 and Ng cell adhesion molecule (NgCAM), two molecules with predominantly axonal expression exhibit homophilic interactions across the extracellular space (axonin- 1/axonin-1 and NgCAM/NgCAM) and a heterophilic interaction (axonin-1-NgCAM) that occurs exclusively in the plane of the same membrane (cis-interaction). Using domain deletion mutants we localized the NgCAM homophilic binding in the Ig domains 1-4 whereas heterophilic binding to axonin-1 was localized in the Ig domains 2-4 and the third FnIII domain. The NgCAM-NgCAM interaction could be established simultaneously with the axonin-1-NgCAM interaction. In contrast, the axonin-1-NgCAM interaction excluded axonin-1/axonin-1 binding. These results and the examination of the coclustering of axonin-1 and NgCAM at cell contacts, suggest that intercellular contact is mediated by a symmetric axonin-12/NgCAM2 tetramer, in which homophilic NgCAM binding across the extracellular space occurs simultaneously with a cis-heterophilic interaction of axonin-1 and NgCAM. The enhanced neurite fasciculation after overexpression of NgCAM by adenoviral vectors indicates that NgCAM is the limiting component for the formation of the axonin-12/NgCAM2 complexes and, thus, neurite fasciculation in DRG neurons.


Asunto(s)
Moléculas de Adhesión Celular Neurona-Glia/química , Moléculas de Adhesión Celular Neurona-Glia/fisiología , Moléculas de Adhesión Celular Neuronal/química , Moléculas de Adhesión Celular Neuronal/fisiología , Ganglios Espinales/fisiología , Neuritas/fisiología , Conformación Proteica , Animales , Animales Recién Nacidos , Sitios de Unión , Moléculas de Adhesión Celular Neurona-Glia/genética , Moléculas de Adhesión Celular Neuronal/genética , Pollos , Contactina 2 , Espacio Extracelular/fisiología , Ratones , Ratones Endogámicos ICR , Modelos Moleculares , Mutagénesis , Neuronas/citología , Neuronas/fisiología , Técnicas de Cultivo de Órganos , Mutación Puntual , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Eliminación de Secuencia , Transfección
12.
J Cell Biol ; 149(4): 951-68, 2000 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10811834

RESUMEN

An interaction of growth cone axonin-1 with the floor-plate NgCAM-related cell adhesion molecule (NrCAM) was shown to play a crucial role in commissural axon guidance across the midline of the spinal cord. We now provide evidence that axonin-1 mediates a guidance signal without promoting axon elongation. In an in vitro assay, commissural axons grew preferentially on stripes coated with a mixture of NrCAM and NgCAM. This preference was abolished in the presence of anti-axonin-1 antibodies without a decrease in neurite length. Consistent with these findings, commissural axons in vivo only fail to extend along the longitudinal axis when both NrCAM and NgCAM interactions, but not when axonin-1 and NrCAM or axonin-1 and NgCAM interactions, are perturbed. Thus, we conclude that axonin-1 is involved in guidance of commissural axons without promoting their growth.


Asunto(s)
Axones/fisiología , Moléculas de Adhesión Celular Neuronal/metabolismo , Moléculas de Adhesión Celular , Inducción Embrionaria , Animales , Sitios de Unión , Adhesión Celular/fisiología , Moléculas de Adhesión Celular Neurona-Glia/metabolismo , Moléculas de Adhesión Celular Neuronal/genética , Células Cultivadas , Embrión de Pollo , Contactina 2 , Conos de Crecimiento/fisiología , Familia de Multigenes , Vías Nerviosas/embriología , Unión Proteica , Proteínas Recombinantes/metabolismo , Médula Espinal/citología , Médula Espinal/embriología , Médula Espinal/cirugía
13.
Curr Biol ; 6(9): 1153-8, 1996 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-8805367

RESUMEN

BACKGROUND: Growth cones at the tips of growing axons move along predetermined pathways to establish synaptic connections between neurons and their distant targets. To establish their orientation, growth cones continuously sample for, and respond to, guidance information provided by cell surfaces and the extracellular matrix. To identify specific guidance cues, growth cones have sensor molecules on their surface, which are expressed differentially during the temporospatial progress of axon outgrowth, at levels that depend on the pattern of neural activity. However, it has not been elucidated whether a change in gene expression can indeed change the molecular composition and, hence, the function of the sensor apparatus of growth cones. RESULTS: We have constructed adenoviral gene transfer vectors of the chicken growth cone sensor molecules axonin-1 and Ng-CAM. Using these vectors, we initiated the expression of axonin-1 and Ng-CAM in rat dorsal root ganglia explants during ongoing neurite outgrowth. Using specific surface immunodetection at varying time points after infection, we found that axonin-1 and Ng-CAM are transported directly to the growth cone and inserted exclusively in the growth cone membrane and not in the axolemma of the axon shaft. Furthermore, we found that axonin-1 and Ng-CAM do not diffuse retrogradely, suggesting that the sensor molecules are integrated into multimolecular complexes in the growth cone. CONCLUSIONS: During axon outgrowth, the pathway sensor apparatus of the growth cone is continuously updated by newly synthesized sensor molecules that originate directly from the transcription/translation machinery. Changes in the expression of sensor molecules may have a direct impact, therefore, on the exploratory function of the growth cone.


Asunto(s)
Axones , Neuritas , Animales , Axones/metabolismo , Moléculas de Adhesión Celular Neurona-Glia/metabolismo , Moléculas de Adhesión Celular Neuronal/metabolismo , Embrión de Pollo , Contactina 2 , Ganglios Espinales/citología , Ganglios Espinales/metabolismo , Inmunohistoquímica , Ratas
14.
J Clin Invest ; 87(5): 1780-6, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1902492

RESUMEN

Escherichia coli heat-labile enterotoxins (LT) are responsible in part for "traveler's diarrhea" and related diarrheal illnesses. The family of LTs comprises two serogroups termed LT-I and LT-II; each serogroup includes two or more antigenic variants. The effects of LTs result from ADP ribosylation of Gs alpha, a stimulatory component of adenylyl cyclase; the mechanism of action is identical to that of cholera toxin (CT). The ADP-ribosyltransferase activity of CT is enhanced by 20-kD guanine nucleotide-binding proteins, known as ADP-ribosylation factors or ARFs. These proteins directly activate the CTA1 catalytic unit and stimulate its ADP ribosylation of Gs alpha, other proteins, and simple guanidino compounds (e.g., agmatine). Because of the similarities between CT and LTs, we investigated the effects of purified bovine brain ARF and a recombinant form of bovine ARF synthesized in Escherichia coli on LT activity. ARF enhanced the LT-I-, LT-IIa-, and LT-IIb-catalyzed ADP ribosylation of agmatine, as well as the auto-ADP ribosylation of the toxin catalytic unit. Stimulation of ADP-ribosylagmatine formation by LTs and CT in the presence of ARF was GTP dependent and enhanced by sodium dodecyl sulfate. With agmatine as substrate, LT-IIa and LT-IIb exhibited less than 1% the activity of CT and LT-Ih. CT and LTs catalyzed ADP-ribosyl-Gs alpha formation in a reaction dependent on ARF, GTP, and dimyristoyl phosphatidylcholine/cholate. With Gs alpha as substrate, the ADP-ribosyltransferase activities of the toxins were similar, although CT and LT-Ih appeared to be slightly more active than LT-IIa and LT-IIb. Thus, LT-IIa and LT-IIb appear to differ somewhat from CT and LT-Ih in substrate specificity. Responsiveness to stimulation by ARF, GTP, and phospholipid/detergent as well as the specificity of ADP-ribosyltransferase activity are functions of LTs from serogroups LT-I and LT-II that are shared with CT.


Asunto(s)
Toxinas Bacterianas/farmacología , Enterotoxinas/farmacología , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Proteínas de Unión al GTP/farmacología , Proteínas de la Membrana/farmacología , Factores de Ribosilacion-ADP , Adenosina Difosfato Ribosa/metabolismo , Toxina del Cólera/farmacología , Guanosina Trifosfato/farmacología , Proteínas Recombinantes/farmacología
15.
Mol Cell Biol ; 11(1): 218-25, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1986222

RESUMEN

Inactivation of the Saccharomyces cerevisiae RAD18 gene confers a mutator phenotype. To determine the specificity of this effect, a collection of 212 spontaneous SUP4-o mutants arising in a rad18 strain was characterized by DNA sequencing. Comparison of the resulting mutational spectrum with that for an isogenic wild-type (RAD18) strain revealed that the rad18 mutator specifically enhanced the frequency of single base pair substitutions. Further analysis indicated that an increase in the frequency of G.C----T.A transversions accounted for the elevated SUP4-o mutation frequency. Thus, rad18 is the first eucaryotic mutator found to generate only a particular base pair substitution. The majority of G.C pairs that were not mutated in the rad18 background were at sites where G.C----T.A events can be detected in SUP4-o, suggesting that DNA sequence context influences the rad18 mutator effect. Transformation of heteroduplex plasmid DNAs into the two strains demonstrated that the rad18 mutator did not reduce the efficiency of correcting G-A or C-T mismatches to G.C pairs or preferentially correct the mismatches to A.T pairs. We propose that the RAD18 gene product might contribute to the fidelity of DNA replication in S. cerevisiae by involvement in a process that serves to limit the formation of G-A and C-T mismatches at template guanine and cytosine sites during DNA synthesis.


Asunto(s)
Reparación del ADN , Mutagénesis , Saccharomyces cerevisiae/genética , Secuencia de Bases , Canavanina/farmacología , ADN de Hongos/genética , Genes Fúngicos , Genes Supresores , Datos de Secuencia Molecular
16.
Mol Cell Biol ; 8(2): 978-81, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3280976

RESUMEN

A collection of 196 spontaneous mutations in the SUP4-o gene of the yeast Saccharomyces cerevisiae was analyzed by DNA sequencing. The classes of mutation identified included all possible types of base-pair substitution, deletions of various lengths, complex alterations involving multiple changes, and insertions of transposable elements. Our findings demonstrate that at least several different mechanisms are responsible for spontaneous mutagenesis in S. cerevisiae.


Asunto(s)
ADN de Hongos/genética , Genes Fúngicos , Mutación , Saccharomyces cerevisiae/genética , Composición de Base , Secuencia de Bases , Datos de Secuencia Molecular , Conformación de Ácido Nucleico
18.
J Neuroimmunol ; 174(1-2): 174-9, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16556466

RESUMEN

In this study, we investigated the affinity, determined by a relative affinity assay, using increasing concentrations of sodium-isothiocyanate to disrupt the antigen antibody binding of neutralizing and non-neutralizing antibodies against interferon-beta (IFNbeta)-1a and -1b in 73 serum samples of MS patients treated with IFNbeta-1a or -1b. Relative affinity values were significantly higher in NAB-positive compared to NAB-negative samples and in samples of IFNbeta-1a-treated patients compared to IFNbeta-1b. A significant positive correlation between relative affinity values and therapy duration indicates affinity maturation as another qualitative factor in IFNbeta neutralization.


Asunto(s)
Anticuerpos/uso terapéutico , Interferón beta/inmunología , Esclerosis Múltiple/terapia , Análisis de Varianza , Anticuerpos/fisiología , Unión Competitiva/inmunología , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Inmunoterapia/métodos , Interferón beta/metabolismo , Esclerosis Múltiple/inmunología , Pruebas de Neutralización/métodos , Factores de Tiempo , Resultado del Tratamiento
19.
Cancer Res ; 49(2): 279-83, 1989 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-2642736

RESUMEN

A collection of 346 mutations arising in the SUP4-o gene of the yeast Saccharomyces cerevisiae following treatment with 1,3-bis(2-chloro-ethyl)-1-nitrosourea (BCNU) or nitrogen mustard was analyzed by DNA sequencing. Both agents induced all possible types of base-pair substitution as well as deletions and double mutations. The base-pair changes consisted primarily of events at G.C pairs and were distributed throughout the gene. However, the distributions differed for the two drugs, and a prominent substitution hotspot was detected for nitrogen mustard. BCNU induced a substantial fraction of deletions the majority of which were recovered at a hotspot encompassing a tract of five G.C pairs. In contrast, nitrogen mustard generated relatively few deletions, but substantially more double mutations were recovered than with treatment with BCNU. Neither agent exhibited a preference for contiguous G.C sites, and more than one quarter of the mutations occurred at G.C sites, flanked by A.T pairs or at A.T pairs indicating that mutagenesis was not restricted to G.C runs. The data indicate that for BCNU and nitrogen mustard, monoadducts may play a role in mutagenesis, and site-specific mutability is influenced by factors in addition to the G.C richness of the sequence involved.


Asunto(s)
Carmustina/farmacología , Genes Fúngicos/efectos de los fármacos , Mecloretamina/farmacología , Saccharomyces cerevisiae/genética , Canavanina/farmacología , Mutación , Saccharomyces cerevisiae/efectos de los fármacos
20.
Cancer Res ; 40(7): 2323-9, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6992984

RESUMEN

Recently, it has been suggested that mitotic recombination is involved in tumor promotion. On this basis, one might expect tumor promoters to be recombinagenic. D7 is a diploid strain of yeast in which both mutation and mitotic recombination can be measured. We have used this strain to assay the known tumor promoters, iodoacetate, anthralin, and 12-O-tetradecanoylphorbol-13-acetate, and the cocarcinogen, catechol, for mutagenicity, recombinagenicity, and the ability to enhance ultraviolet light (UV)-induced genetic events. In the absence of preirradiation with UV, iodoacetate was found to be recombinagenic whereas catechol was mutagenic; however, in both cases, the effects were small. Iodoacetate, anthralin, and catechol potentiated UV-induced mitotic crossing-over, aberrant colony formation, and mutation, while catechol also increased UV-induced gene conversion. We were unable to detect any mutagenic or recombinagenic effect of 12-O-tetradecanoyl-phorbol-13-acetate in either whole cells or spheroplasts. Our results do not indicate any consistent correlation between tumor-promoting activity and the ability of an agent to induce mitotic recombination in yeast. However, the ability to potentiate UV-induced mutation and mitotic recombination may reflect the cocarcinogenic activity of certain promoters.


Asunto(s)
Antracenos/farmacología , Antralina/farmacología , Catecoles/farmacología , Yodoacetatos/farmacología , Mutación/efectos de los fármacos , Recombinación Genética/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Carcinógenos , Cocarcinogénesis , Intercambio Genético , Conversión Génica , Mitosis/efectos de los fármacos , Mutágenos , Ésteres del Forbol/farmacología , Fármacos Sensibilizantes a Radiaciones , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/efectos de la radiación , Rayos Ultravioleta
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