RESUMO
Spray deposition of thin films and coatings is a widely used manufacturing process owing to its low cost, versatility and simple implementation. The objective of the presented experiments was to investigate whether X-ray absorption measurements on solutes carried by aerosols are possible, and what count rates can be achieved depending on solution flow through and the resulting mass density in the interrogation volume. The investigated prototypical spray aerosol was InCl(3) dissolved in water or ethanol dispersed via an ultrasonic nebulizer. InCl(3) spray is essential for the ion layer gas reaction process used for the deposition of In(2)S(3) buffer layers for highly efficient chalcopyrite solar cells. The discussed experiments demonstrate that measurements are possible, but that the achievement of good signal-to-noise ratios requires extended sampling times and concentrated solutions.
RESUMO
Since transglutaminases create covalent gamma-glutamyl-epsilon-lysine cross-links between extracellular matrix proteins they are prime candidates for stabilizing tissue during wound healing. Therefore, we studied the temporo-spatial expression of transglutaminase activity in skin regenerating from cultured epithelial autografts in severely burned children by the specific incorporation of monodansylcadaverine into cryostat sections from skin biopsies obtained between 5 d to 17 mo after grafting. The dansyl label was subsequently immunolocalized in the epidermis, dermal connective tissue, and along the basement membrane. Incubation of cryosections of normal and regenerating skin with purified tissue transglutaminase confirmed the dermo-epidermal junction and the papillary dermis as targets for this enzyme and revealed that in regenerating skin transamidation of the basement membrane zone was completed only 4-5 mo after grafting. Immunoelectron microscopy revealed that three distinct regions on the central portion of anchoring fibrils were positive for monodansylcadaverine in normal skin which were negative during the initial phase of de novo formation of anchoring fibrils in regenerating skin. Biochemically, we identified collagen VII as potential substrate for tissue transglutaminase. Thus, tissue transglutaminase appears to play an important role not only in cross-linking of the papillary dermis but also of the dermo-epidermal junction in particular.
Assuntos
Adesão Celular/fisiologia , Matriz Extracelular/fisiologia , Regeneração , Fenômenos Fisiológicos da Pele , Transglutaminases/fisiologia , Adolescente , Sequência de Aminoácidos , Queimaduras/cirurgia , Criança , Pré-Escolar , Colágeno/metabolismo , Reagentes de Ligações Cruzadas , Epiderme/fisiologia , Matriz Extracelular/ultraestrutura , Feminino , Humanos , Queratinócitos/transplante , Queratinócitos/ultraestrutura , Masculino , Microscopia Imunoeletrônica , Modelos Biológicos , Dados de Sequência Molecular , Pele/ultraestrutura , Transglutaminases/imunologia , Transglutaminases/isolamento & purificação , Cicatrização/fisiologiaRESUMO
Anchoring fibrils are adhesive suprastructures that ensure the connection of the epidermal basement membrane with the dermal extracellular matrix. The fibrils represent polymers of collagen VII, the major structural fibril component, but may also contain other proteins. Remarkable progress has been made in the last few years in understanding the functions of skin basement membrane components including the anchoring fibrils. Novel insights into the biology of the anchoring fibrils have been gained from experimental studies on dystrophic epidermolysis bullosa (DEB), a group of inherited blistering disorders caused by mutations in the gene for collagen VII, COL7A1. Mutation analyses of DEB families have disclosed more than 100 COL7A1 gene defects so far, but the unusual complexity of the mutation constellations and their biological consequences are only beginning to emerge. In analogy to heritable disorders of other collagen genes, predictable phenotypes of COL7A1 mutations causing premature termination codons or dominant negative interference have been observed. However, collagen VII seems to represent a remarkable exception among collagens in that many mutations, including heterozygous glycine substitutions and deletions, lead to minimal phenotypes, or to no phenotype at all. In contrast to fibrillar collagens, structural abnormalities of collagen VII molecules in anchoring fibrils appear to be tolerated to a certain extent. However, the mild DEB phenotypes can be severely modulated by a second aberration in individuals compound heterozygous for two different COL7A1 mutations. Therefore, not only definition of mutation(s) but also cell biological, protein chemical and suprastructural studies of the mutated molecules yield novel insight into the molecular pathomechanisms underlying disease.
Assuntos
Derme/fisiologia , Epiderme/fisiologia , Epidermólise Bolhosa Distrófica/genética , Animais , Autoanticorpos/metabolismo , Colágeno/biossíntese , Colágeno/genética , Colágeno/imunologia , Derme/anatomia & histologia , Derme/patologia , Epiderme/anatomia & histologia , Epiderme/patologia , Epidermólise Bolhosa Distrófica/patologia , Heterogeneidade Genética , Genótipo , Humanos , Ligantes , FenótipoRESUMO
BACKGROUND: Since widespread screenings for hypothyreosis were started in 1981 in Germany, the numbers of mental and physical handicaps due to hypothyroidism are reduced markedly. The aim of this study is to evaluate the actual efficiency of the newborn screenings in Germany using in the federal state "Hessen". METHODS/SUBJECTS: All children born between 1988 and 1992 with suspicions laboratory results in the screening examination were contacted personally and statements concerning the screening itself and the physical and mental development were gathered from their parents, doctors and teachers. RESULTS: 99.1% of all hessian newborns born between 1988 and 1992 were included into the screening for hypothyreosis. The incidence of congenital hypothyreosis in general was 1:3 313. An etiological classification was possible in 77% of the patients which is divided as follows: 40% athyreosis, 24% hypoplasia of the thyroid, 8% dyshormonogenesis, 5% ektopia of the thyroid. In 67% of the cases hormone substitution was initiated during the first 14 days of life. In 23.9% it was started in the third week, in 6.8% in the fourth week and only in 2.3% of the patients treatment was started later on. The physical development of the children with congenital hypothyreosis can be regarded as widely normal. The school achievement was moderately retarded even when treatment was started in the early neonatal period. CONCLUSIONS: The screening for hypothyreosis is well established in Hessen concerning tracking, organisation and analysis. There are short comings concerning the follow ups of children with suspicions findings, which shall be overcome by creating a new position. The long-term-follow-up according to the guidelines of the "Arbeitsgemeinschaft Pädiatrische Endokrinologie" is of central interest. Furthermore compliance is improved by regular personal counselling with the parents.
Assuntos
Hipotireoidismo Congênito/diagnóstico , Deficiências do Desenvolvimento/prevenção & controle , Deficiência Intelectual/prevenção & controle , Triagem Neonatal , Adolescente , Criança , Pré-Escolar , Hipotireoidismo Congênito/tratamento farmacológico , Hipotireoidismo Congênito/epidemiologia , Estudos Transversais , Deficiências do Desenvolvimento/diagnóstico , Seguimentos , Alemanha , Humanos , Incidência , Lactente , Recém-Nascido , Deficiência Intelectual/diagnóstico , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Testes de Função Tireóidea , Glândula Tireoide/anormalidades , Hormônios Tireóideos/uso terapêutico , Tireotropina/sangueRESUMO
In the screening of newborns for congenital hypothyroidism, filter paper cards act as sample carriers for capillary blood specimens, and for reference quantities of the measured hormones. Therefore, the quality of the filter paper is especially important and must be taken into account. Different types of filter paper and different guide marks on the paper surface for spotting blood specimens were investigated. The hormone distribution within the dried blood spot and the time necessary to extract the hormones were examined in relation to the sensitivity and yield of the test kit.
Assuntos
Hipotireoidismo Congênito , Recém-Nascido , Papel/normas , Tireotropina/sangue , Humanos , Hipotireoidismo/sangue , Radioimunoensaio , Kit de Reagentes para DiagnósticoRESUMO
Using the monoclonal antibody GDA-J/F3, a 50-kDa noncollagenous component of human skin basement membrane zone was identified. Immunofluorescence stainings of normal human skin with the GDA-J/F3 antibody showed a linear fluorescence decorating the basement membrane zone. With immunoelectron microscopy, the epitope was localized to the insertion points of the anchoring fibrils into the lamina densa. The antigen is distinct from collagen VII, from the main structural protein of the anchoring fibrils, and from several other structural molecules of the basement membrane zone, because the GDA-J/F3 antibody did not react with purified basement membrane components in vitro. In serum-free cultures, the antigen was synthesized and secreted by normal and transformed human keratinocytes and to a lesser extent by normal human skin fibroblasts. Immunoprecipitation of radiolabeled epithelial cell-conditioned medium with the GDA-J/F3 antibody yielded two polypeptides that migrated on SDS-polyacrylamide gel electrophoresis with apparent molecular masses of 46 and 50 kDa under nonreducing conditions. Using reducing gels, only the 50-kDa polypeptide was observed. The antigen was resistant to digestion with bacterial collagenase but sensitive to trypsin and pepsin. It also bound to heparin and DEAE cellulose at low ionic strength and alkaline pH. These findings indicate that the GDA-J/F3 antigen is a small globular disulphide-bonded protein with a potential to interact with basement membrane proteoglycans. Integration of the GDA-J/F3 antigen into the histoarchitecture of the dermo-epidermal junction is dependent on the presence of collagen VII, because the GDA-J/F3 epitope was missing in several patients with a genetic blistering disorder of the skin, epidermolysis bullosa dystrophica, who lacked collagen VII and anchoring fibrils.
Assuntos
Anticorpos Monoclonais/imunologia , Proteínas de Transporte/análise , Proteínas de Membrana/análise , Pele/imunologia , Espermatozoides/imunologia , Membrana Basal/imunologia , Proteínas de Transporte/imunologia , Moléculas de Adesão Celular/análise , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Colágeno/metabolismo , Endopeptidases/metabolismo , Epitélio/imunologia , Epitopos/análise , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Masculino , Proteínas de Membrana/imunologia , Microscopia Imunoeletrônica , Peso Molecular , CalininaRESUMO
Most patients with epidermolysis bullosa acquisita develop an autoimmune response to the non-collagenous (NC) 1 domain of type VII collagen. We report a 4-year-old girl of white European descent presenting with widespread blistering disease involving the face, hands, genital area and oral mucosa. Histopathology revealed subepidermal blisters, and linear deposits of IgG and C3 were seen along the dermal-epidermal junction on direct immunofluorescence (IF) microscopy of a perilesional skin biopsy. On indirect IF microscopy, circulating autoantibodies exclusively stained the dermal side of 1 mol L-1 NaCl-split skin. The patient's IgG autoantibodies labelled a 290-kDa protein on Western blotting of dermal extracts, and reacted with the NC1, NC2 and triple helical domains of type VII collagen on immunoblotting of recombinant and cell-derived fragments obtained by pepsin and collagenase digestion of the full-length protein. Oral methylprednisolone and dapsone led to clearance of lesions, which healed with mild scarring and milia formation. Treatment was discontinued after 1 year and the patient has now been in remission for more than 3 years.
Assuntos
Doenças Autoimunes/imunologia , Colágeno Tipo VII/imunologia , Epidermólise Bolhosa Adquirida/imunologia , Autoanticorpos/análise , Autoantígenos/imunologia , Doenças Autoimunes/patologia , Pré-Escolar , Epidermólise Bolhosa Adquirida/patologia , Feminino , Humanos , Pele/imunologiaRESUMO
Epidermolysis bullosa acquisita and bullous systemic lupus erythematosus are autoimmune bullous disorders, with tissue-bound and circulating autoantibodies reactive with the noncollagenous NC1 domain of type VII collagen (C-VII). Here, we describe a novel acquired bullous dermatosis with autoantibodies against the triple-helical domain of C-VII. Three patients, all Japanese children, presented with widespread inflammatory tense blisters. Histologically, subepidermal tissue separation was noted with inflammatory infiltrate in the superficial dermis. Direct immunofluorescence staining revealed linear IgG/C3 deposits along the dermal-epidermal junction. Circulating IgG anti-basement membrane zone autoantibodies stained the dermal side of normal skin separated with 1 M NaCl. Direct and indirect immunoelectron microscopy using colloidal gold labeling showed that patient sera reacted with anchoring fibrils. The gold particles were localized both near the lamina densa and on the central banded portion of the fibrils. The sera reacted with C-VII in immunoblots. Epitope analyses with natural and recombinant fragments of C-VII disclosed that the sera did not recognize the NC1 domain of C-VII, but the central triple-helical domain of this anchoring fibril protein. Thus, the present probands show a hitherto unrecognized variant of epidermolysis bullosa acquisita, with autoantibodies against epitopes in the collagenous domain of C-VII.