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1.
J Eur Acad Dermatol Venereol ; 36(11): 2181-2189, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35796163

RESUMEN

BACKGROUND: Bullous pemphigoid (BP), the by far most frequent autoimmune blistering skin disease (AIBD), is immunopathologically characterized by autoantibodies against the two hemidesmosomal proteins BP180 (collagen type XVII) and BP230 (BPAG1 or dystonin). Several comorbidities and potentially disease-inducing medication have been described in BP, yet a systematic analysis of these clinically relevant findings and autoantibody reactivities has not been performed. OBJECTIVE: To determine associations of autoantibody reactivities with comorbidities and concomitant medication. METHODS: In this prospective multicenter study, 499 patients diagnosed with BP in 16 European referral centers were included. The relation between anti-BP180 NC16A and anti-BP230 IgG ELISA values at the time of diagnosis as well as comorbidities and concomitant medication collected by a standardized form were analysed. RESULTS: An association between higher serum anti-BP180 reactivity and neuropsychiatric but not atopic and metabolic disorders was observed as well as with the use of insulin or antipsychotics but not with dipeptidyl peptidase-4 (DPP4) inhibitors, inhibitors of platelet aggregation and L-thyroxine. The use of DPP4 inhibitors was associated with less anti-BP180 and anti-BP230 reactivity compared with BP patients without these drugs. This finding was even more pronounced when compared with diabetic BP patients without DPP4 inhibitors. Associations between anti-BP180 and anti-BP230 reactivities were also found in patients using insulin and antipsychotics, respectively, compared with patients without this medication, but not for the use of inhibitors of platelet aggregation, and L-thyroxine. CONCLUSION: Taken together, these data imply a relation between autoantibody reactivities at the time of diagnosis and both neuropsychiatric comorbidities as well as distinct concomitant medication suggesting a link between the pathological immune mechanisms and clinical conditions that precede the clinically overt AIBD.


Asunto(s)
Antipsicóticos , Inhibidores de la Dipeptidil-Peptidasa IV , Insulinas , Penfigoide Ampolloso , Enfermedad del Suero , Antipsicóticos/efectos adversos , Autoanticuerpos , Autoantígenos , Vesícula , Dipeptidil Peptidasa 4/uso terapéutico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Distonina , Humanos , Hipoglucemiantes/uso terapéutico , Inmunoglobulina G , Insulinas/uso terapéutico , Colágenos no Fibrilares , Estudios Prospectivos , Tiroxina/uso terapéutico
2.
Br J Dermatol ; 182(6): 1437-1448, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31487386

RESUMEN

BACKGROUND: Impaired growth and anaemia are major extracutaneous complications of epidermolysis bullosa (EB), but data on their development are lacking. OBJECTIVES: To determine the clinical course of growth and anaemia in children with EB and clarify the impact of nutritional compromise, inflammation and genetic factors. METHODS: A retrospective study was conducted of 200 children, 157 with recessive dystrophic EB (RDEB) and 43 with junctional EB (JEB)-generalized intermediate, followed at the main referral centre in Germany. Growth charts were calculated using the modified LMS method and were correlated with parameters of anaemia, nutrition, inflammation and the molecular defect in a linear model. RESULTS: In our cohort of patients with RDEB, weight impairment started at 12-18 months old; by the age of 10 years, 50% showed wasting. The predicted median weight at age 20 years was 35·2 kg for men and 40·1 kg for women. In JEB, growth resembled that of healthy children. Anaemia was present from the second year of life onwards in RDEB and JEB. Low levels of haemoglobin, iron, vitamin D, zinc and albumin, high levels of C-reactive protein, and absence of collagen VII correlated significantly with low weight in RDEB. No correlation was observed in JEB. CONCLUSIONS: The results highlight that nutritional compromise occurs early in children with RDEB and therefore may require interventions as of the first year or two of life. What's already known about this topic? Children with epidermolysis bullosa (EB) suffer from failure to thrive and anaemia as major extracutaneous complications. The course of growth and the development of anaemia in EB are poorly characterized. What does this study add? A molecularly well characterized cohort of 200 children with EB was followed with regard to anthropometrics, anaemia and inflammation. We demonstrate early onset of growth failure and anaemia, most pronounced in the subset of recessive dystrophic EB. Awareness of early growth delay and nutritional deficiencies will improve EB care in daily practice.


Asunto(s)
Anemia , Epidermólisis Ampollosa Distrófica , Epidermólisis Ampollosa , Adulto , Anemia/etiología , Niño , Estudios de Cohortes , Epidermólisis Ampollosa/complicaciones , Femenino , Alemania , Humanos , Lactante , Masculino , Estudios Retrospectivos , Adulto Joven
6.
J Appl Microbiol ; 108(3): 789-799, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19702859

RESUMEN

AIM: To complete our study on tannin degradation via gallic acid by the biotechnologically interesting yeast Arxula adeninivorans as well as to characterize new degradation pathways of hydroxylated aromatic acids. METHODS AND RESULTS: With glucose-grown cells of A. adeninivorans, transformation experiments with hydroxylated derivatives of benzoic acid were carried out. The 12 metabolites were analysed and identified by high performance liquid chromatography and GC/MS. The yeast is able to transform the derivatives by oxidative and nonoxidative decarboxylation as well as by methoxylation. The products of nonoxidative decarboxylation of protocatechuate and gallic acid are substrates for further ring fission. CONCLUSION: Whereas other organisms use only one route of transformation, A. adeninivorans is able to carry out three different pathways (oxidative, nonoxidative decarboxylation and methoxylation) on one hydroxylated aromatic acid. The determination of the KM-values for protocatechuate and gallic acid in crude extracts of cells of A. adeninivorans cultivated with protocatechuate and gallic acid, respectively, suggests that the decarboxylation of protocatechuate and gallic acid may be catalysed by the same enzyme. SIGNIFICANCE AND IMPACT OF THE STUDY: This transformation pathway of protocatechuate and gallic acid via nonoxidative decarboxylation up to ring fission is novel and has not been described so far. This is also the first report of nonoxidative decarboxylation of gallic acid by a eukaryotic micro-organism.


Asunto(s)
Ácido Gálico/metabolismo , Parabenos/metabolismo , Saccharomycetales/metabolismo , Descarboxilación , Hidroxibenzoatos/metabolismo , Oxidación-Reducción , Saccharomycetales/crecimiento & desarrollo , Taninos/metabolismo
8.
Amino Acids ; 37(2): 315-21, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18695937

RESUMEN

Unprotected L-phenylalanine was derivatized by an innovative enzymatic method by means of laccases from Pycnoporus cinnabarinus and Myceliophthora thermophila. During the incubation of L-phenylalanine with para-hydroquinones using laccase as biocatalyst, one or two main products were formed. Dependent on the substitution grade of the hydroquinones mono- and diaminated products were detected. Differences of the used laccases are discussed. The described reactions are of interest for the derivatization of amino acids and a synthesis of pharmacological-active amino acid structures in the field of white biotechnology.


Asunto(s)
Carbono/metabolismo , Proteínas Fúngicas/metabolismo , Hidroquinonas , Lacasa/metabolismo , Nitrógeno/química , Fenilalanina , Carbono/química , Hidroquinonas/química , Hidroquinonas/metabolismo , Estructura Molecular , Fenilalanina/química , Fenilalanina/metabolismo , Pycnoporus/enzimología
9.
Appl Microbiol Biotechnol ; 84(6): 1095-105, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19455326

RESUMEN

A laccase from the aquatic ascomycete Phoma sp. UHH 5-1-03 (DSM 22425) was purified upon hydrophobic interaction and size exclusion chromatography (SEC). Mass spectrometric analysis of the laccase monomer yielded a molecular mass of 75.6 kDa. The enzyme possesses an unusual alkaline isoelectric point above 8.3. The Phoma sp. laccase undergoes pH-dependent dimerisation, with the dimer ( approximately 150 kDa, as assessed by SEC) predominating in a pH range of 5.0 to 8.0. The enzyme oxidises common laccase substrates still at pH 7.0 and 8.0 and is remarkably stable at these pH values. The laccase is active at high concentrations of various organic solvents, all together indicating a considerable biotechnological potential. One laccase gene (lac1) identified at the genomic DNA level and transcribed in laccase-producing cultures was completely sequenced. The deduced molecular mass of the hypothetical protein and the predicted isoelectric point of 8.1 well agree with experimentally determined data. Tryptic peptides of electrophoretically separated laccase bands were analysed by nano-liquid chromatography-tandem mass spectrometry. By using the nucleotide sequence of lac1 as a template, eight different peptides were identified and yielded an overall sequence coverage of about 18%, thus confirming the link between lac1 and the expressed laccase protein.


Asunto(s)
Ascomicetos/enzimología , Lacasa/química , Lacasa/genética , Ascomicetos/genética , Cromatografía en Gel , Clonación Molecular , ADN Bacteriano/análisis , ADN Bacteriano/genética , Estabilidad de Enzimas , Genes Bacterianos , Concentración de Iones de Hidrógeno , Microbiología Industrial , Punto Isoeléctrico , Lacasa/metabolismo , Datos de Secuencia Molecular , Peso Molecular , Multimerización de Proteína , Análisis de Secuencia de ADN , Espectrometría de Masas en Tándem , Microbiología del Agua
10.
J Phys Condens Matter ; 19(7): 076101, 2007 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-22251584

RESUMEN

The susceptibility of aryl-substituted polysilylenes to photodegradation by ultraviolet (UV) radiation is examined on the prototypical materials poly[methyl(phenyl)silylene] (PMPSi) and poly[(biphenyl-4-yl)methylsilylene] (PBMSi). We extend the scope of our last paper (Schauer et al 2004 Polym. Degrad. Stabil. 84 383) with the elucidation of the degradation mechanisms for two different degradation wavelengths: 266 and 355 nm. The main purpose of this paper was to study photoluminescence (PL) after major degradation, predominantly in long-wavelength range 400-600 nm, studying the disorder, dangling bonds (DBs) and weak bonds (WBs) created by the degradation process. We claim that the PL of the 500-600 nm band is related to the existence of WBs on the Si chain and originates in the σ(*)-σ exciton migration at room temperature by diffusion, free electron-hole formation, trapping in WBs and subsequent radiative recombination by tunnelling. Increase of the normalized PL 520-540 nm band after UV degradation can be then evaluated as the increase of the density of states (DOS) of WBs. The efficiency of the WB creation in PMPSi is greater for 266 nm irradiation, supporting the notion of the suppressed exciton transport compared to the less energetical photon of 355 nm, where the WB creation is lowered due to the exciton migration to longer segments and/or already existing defects. For PBMSi the WB creation kinetics for 355 nm degradation is similar to that of PMPSi. The 266 nm degradation results then support the model calculations of DB and WB reconstruction in the more rigid Si skeleton.

11.
Amino Acids ; 31(4): 409-19, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16583315

RESUMEN

We have studied the enzymatic derivatization of amino acids by use of the polyphenol oxidase laccase. Derivatization of L-tryptophan was achieved by enzymatic crosslinking with the laccase substrate 2,5-dihydroxy-N-(2-hydroxyethyl)-benzamide. The main product (yield up to 70%) was identified as the quinoid compound 2-[2-(2-hydroxy-ethylcarbamoyl)-3,6-dioxo-cyclohexa-1,4-dienylamino]-3-(1H-indol-3-yl)- propionic acid and demonstrates that laccase-catalyzed C-N-coupling occurred on the amino group of the aliphatic side chain. These enzyme based reactions provide a simple and fast method for the derivatization of unprotected amino acids.


Asunto(s)
Benzamidas/química , Hidroquinonas/química , Lacasa/metabolismo , Triptófano/análogos & derivados , Hidroquinonas/metabolismo , Lacasa/aislamiento & purificación , Triptófano/química , Triptófano/metabolismo
12.
Chemosphere ; 36(10): 2321-35, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9566302

RESUMEN

By varying selected environmental factors, the degradation and mineralization of biaryl compounds by the bacterium Ralstonia pickettii in soil and compost were investigated. An optimized soil moisture and enhanced bioavailability by using the nonionic surfactant Tween 80 were of great importance for the degradation rates of biaryl compounds like biphenyl and 4-chlorobiphenyl by cells of Ralstonia picketti SBUG 290 inoculated into soil. Additionally, degradation of these compounds by the investigated strain in soil was strongly dependent upon the medium of precultivation. Also the influence of temperature and soil pH-value was tested. In contrast to the used soil, the autochthonous flora of the compost seemed to have a higher physiological activity. All investigated compounds (biphenyl, 4-chlorobiphenyl and dibenzofuran) were degraded quickly in compost. Inoculation with the investigated bacterium did not enhance the degradation rates significantly.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Bacilos y Cocos Aerobios Gramnegativos/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Suelo/análisis , Contaminantes Ocupacionales del Aire/análisis , Biodegradación Ambiental , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Dióxido de Carbono/metabolismo , Cinética , Minerales/química , Contaminantes del Suelo/análisis
13.
J Appl Microbiol ; 98(3): 635-45, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15715866

RESUMEN

AIMS: Biphenyl-degrading bacteria are able to metabolize dibenzofuran via lateral dioxygenation and meta-cleavage of the dihydroxylated dibenzofuran produced. This degradation was considered to be incomplete because accumulation of a yellow-orange ring-cleavage product was observed. In this study, we want to characterize the 1,2-dihydroxydibenzofuran cleaving enzyme which is involved in dibenzofuran degradation in the bacterium Ralstonia sp. SBUG 290. METHODS AND RESULTS: In this strain, complete degradation of dibenzofuran was observed after cultivation on biphenyl. The enzyme shows a wide substrate utilization spectrum, including 1,2-dihydroxydibenzofuran, 2,3-dihydroxybiphenyl, 1,2-dihydroxynaphthalene, 3- and 4-methylcatechol and catechol. MALDI-TOF analysis of the protein revealed a strong homology to the bphC gene products. We therefore cloned a 3.2 kb DNA fragment containing the bphC gene of Ralstonia sp. SBUG 290. The deduced amino acid sequence of bphC is identical to that of the corresponding gene in Pseudomonas sp. KKS102. The bphC gene was expressed in Escherichia coli and the meta-fission activity was detected using either 2,3-dihydroxybiphenyl or 1,2-dihydroxydibenzofuran as substrate. CONCLUSIONS: These results demonstrate that complete degradation of dibenzofuran by biphenyl degraders can occur after initial oxidation steps catalysed by gene products encoded by the bph-operon. The ring fission of 1,2-dihydroxydibenzofuran is catalysed by BphC. Differences found in the metabolism of the ring fission product of dibenzofuran among biphenyl degrading bacteria are assumed to be caused by different substrate specificities of BphD. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows for the first time that the gene products of the bph-operon are involved in the mineralization of dibenzofuran in biphenyl degrading bacteria.


Asunto(s)
Benzofuranos/metabolismo , Dioxigenasas/metabolismo , Genes Bacterianos , Ralstonia/genética , Ralstonia/metabolismo , Microbiología del Suelo , Secuencia de Aminoácidos , Biodegradación Ambiental , Secuencia Conservada , Dioxigenasas/análisis , Dioxigenasas/genética , Escherichia coli , Expresión Génica , Datos de Secuencia Molecular , Mapeo Peptídico , Alineación de Secuencia
14.
Zentralbl Mikrobiol ; 143(3): 195-206, 1988.
Artículo en Alemán | MEDLINE | ID: mdl-3051786

RESUMEN

Oxygen is one of the most important environmental factors for microorganisms. Many metabolic reactions of aerobic or facultative anaerobic bacteria are influenced by varying oxygen concentrations. A lot of enzyme reactions in respiration processes, catabolism, anabolism and gene expression depend upon oxygen. Other enzymes such as nitrogenase or hydrogenases can be inhibited by increasing oxygen levels. Also complex metabolic processes including anaerobic respiration and fermentations are regulated by oxygen. Finally toxic oxygen derivatives have to be eliminated by living cells to overcome damage of cell constituents. In this way also bacteria which are included into the nitrogen cycle in the nature are influenced by oxygen. The different strategies of microorganisms to protect their nitrogenases for oxygen inactivation and the regulation of dissimilative nitrate reduction by oxygen are demonstrated in detail.


Asunto(s)
Bacterias Aerobias/metabolismo , Bacterias Anaerobias/metabolismo , Nitrógeno/metabolismo , Oxígeno/metabolismo , Bacterias Aerobias/enzimología , Bacterias Anaerobias/enzimología , Modelos Biológicos
15.
J Med Philos ; 17(6): 573-87, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1479307

RESUMEN

Using the right to die and the United States Supreme Court case of Cruzan v. Director, Missouri Department of Health as exemplars, this article explores the notion of third-order decisionmaking. If first order decisionmaking is about what should happen, and second-order decisionmaking is about who should decide what should happen, then third-order decisionmaking is about who should decide who decides. This turns out to be an apt characterization of constitutionalism, which is centrally concerned with the allocation of responsibility for making decisions about the allocation of responsibility. Deference to erroneous second-order decisions, as in the Cruzan case itself, may merely be an example of this central feature of constitutionalism.


Asunto(s)
Coma , Técnicas de Apoyo para la Decisión , Tutores Legales , Cuidados para Prolongación de la Vida/legislación & jurisprudencia , Derecho a Morir/legislación & jurisprudencia , Decisiones de la Corte Suprema , Directivas Anticipadas/legislación & jurisprudencia , Ética Médica , Femenino , Humanos , Rol Judicial , Filosofía Médica , Estados Unidos
16.
J Microsc ; 184(Pt 2): 81-7, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8972096

RESUMEN

The processing of yeast cells for scanning electron microscopy by conventional sequential fixation with glutaraldehyde and osmium tetroxide and subsequent dehydration and critical point-drying caused pronounced deformation and visible shrinkage in all basidiomycetous and ascomycetous yeast strains studied. The mean cell diameter decreased to nearly 60 and 70%, respectively. After an additional sequential fixation with 1% tannic acid and 0.5% uranyl acetate the cell shrinkage was significantly reduced, but the most important result was a considerable reduction of wrinkling and deformation of the yeast cells.


Asunto(s)
Levaduras/ultraestructura , Microscopía Electrónica de Rastreo , Fijación del Tejido
17.
J Basic Microbiol ; 25(10): 653-61, 1985.
Artículo en Alemán | MEDLINE | ID: mdl-4093875

RESUMEN

Two fungal strains of the genus Sporothrix, isolated from industrial waste water, were characterized with respect to some morphological and physiological properties. After comparison with other species of the genus Sporothrix, the fungal strains are described as Sporothrix nivea, n. sp. Among 28 carbon sources tested, such as sugars, polysaccharides, alcohols, organic acids, and hydrocarbons, 23 are utilized. The most remarkable property of Sporothrix nivea is the utilization of both n-alkanes and methanol.


Asunto(s)
Alcanos/metabolismo , Hidrocarburos/metabolismo , Metanol/metabolismo , Sporothrix/metabolismo , Alcoholes/metabolismo , Metabolismo de los Hidratos de Carbono , Medios de Cultivo , Polisacáridos/metabolismo , Sporothrix/clasificación , Sporothrix/crecimiento & desarrollo , Sporothrix/aislamiento & purificación
18.
Zentralbl Mikrobiol ; 144(4): 219-30, 1989.
Artículo en Alemán | MEDLINE | ID: mdl-2678822

RESUMEN

Dimorphic fungi can grow as mycelial phase and as yeast phase. The change of growth form is effected by an altered programme in gene expression, which is induced either in certain stages of ontogenesis or by environmental factors. Therefore it is necessary to distinguish ontogenetically conditioned (irreversible) and environment conditioned (reversible) dimorphism. The first is characteristic for dimorphic Ustomycetes, Basidiomycetes and related anamorphs as well as for Taphrinales; the second for the majority of dimorphic Ascomycetes, Endomycetes, and related anamorphs. The integration of dimorphic fungi in the systems of filamentous fungi and of yeasts--which originally have been elaborated rather independently--was difficult in many cases. In recent times, the study of certain ultrastructural and biochemical-physiological characters has much facilitated the taxonomic arrangement of dimorphic fungi and has allowed to demonstrate some phylogenetic relations among filamentous, dimorphic, and yeast fungi. The authors hold the concept that yeasts have evolved from filamentous resp. dimorphic fungi by neotenic simplification.


Asunto(s)
Hongos/crecimiento & desarrollo , Hongos/clasificación , Hongos/citología , Hongos/genética , Expresión Génica , Filogenia , Levaduras/clasificación , Levaduras/citología , Levaduras/genética , Levaduras/crecimiento & desarrollo
19.
Mycoses ; 42 Suppl 1: 12-21, 1999.
Artículo en Alemán | MEDLINE | ID: mdl-10592710

RESUMEN

Candida is a heterogeneous genus which contains about a quarter of all yeast species. It includes not only species of uncertain affiliation but also unrelated strains whose phylogenetic relationships have not been resolved. A great variety of CoQ types are present in the genus, the mol % G + C ranges from 30-63%, and species that were found to sporulate have teleomorphic counterparts in 11 different genera. Candida species are mainly associated with plants, rotting vegetation, with insects which feed on plants or with food. In line with this, 71% of Candida species utilize xylose (wood degradation), 57% of species use cellobiose (cellulose degradation), 29% oxidize aliphatic hydrocarbons (components of plant cuticula), 27% of species degrade starch as a plant storage material, and 7% utilize methanol as a possible metabolite from pectin catabolism. 85% of species require individual vitamins produced mainly in plant materials. 65% of Candida species are not able to grow at temperatures of 37 degrees C. In comparison only relatively few species occur normally in humans and other warm blooded animals. About 16% of type strains and selected strains for comparative purposes (CBS) were isolated from human specimens. Perhaps up to 10% of Candida species may be of medical importance, though this has so far only been clearly demonstrated for less than 5% of currently known species.


Asunto(s)
Candida/clasificación , Composición de Base , Candida/química , Candida/fisiología , Candida/ultraestructura , Ecología , Técnicas de Tipificación Micológica , Plantas/microbiología , Ubiquinona/aislamiento & purificación
20.
Antonie Van Leeuwenhoek ; 54(2): 179-88, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3395111

RESUMEN

77 Ascomycetous, basidiomycetous as well as imperfect yeast strains of 46 different species and 20 genera were tested for growth with the substrates n-octane, n-hexadecane, and phenol. Of 59 yeast strains with ascomycetous cell wall structure 33 grew on hydrocarbons and 32 on phenol. No yeast strain out of 26 which are unable to use n-alkanes as a source of carbon and energy grew on phenol. In comparison with the latter 32 out of 33 n-hexadecane assimilating yeasts were also capable of using phenol. All n-octane utilizing yeasts of this group also assimilate phenol as a carbon source for growth. The correlation of the hydrocarbon assimilation with the phenol assimilation seems to be not so strong in the basidiomycetous yeasts. 7 out of 18 strains from this group grew on n-hexadecane and 13 on phenol. Furthermore, it could be shown that the use of hydrocarbons and phenol (as well as methanol) is strongly correlated with the coenzyme Q structure of the respective yeast strain. The results are discussed with respect to the particular chemical properties of the substrates used and the fact that coenzyme Q structure is considered to be an important marker of evolutionary relationships among yeasts.


Asunto(s)
Basidiomycota/metabolismo , Fenoles/metabolismo , Levaduras/metabolismo , Fenol , Especificidad de la Especie
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