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1.
Animal ; 15(6): 100238, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34030032

RESUMO

The objective of this study was to describe the population structure and inbreeding level of the population of Polish Red Cattle (PRC). The structure of the breed was analysed in the context of the existing genetic resources conservation programme. The level of genetic diversity and the effective population size were also determined. The analyses were carried out based on pedigree records of 9 170 animals. Data and pedigree information were collected during the time period of 1950-2014. Records were collected by the National Research Institute of Animal Production in Balice, Poland. The population structure was analysed using the CFC programme. All the animals were grouped into five classes according to their inbreeding coefficient: the first class included non-inbred animals; and the next classes included inbred animals 0% < F ≤ 5%, 5% < F ≤ 10%, 10% < F ≤ 20%, 20% < F ≤ 30% or F > 30%. The average inbreeding in PRC population was 4% and there were 2 182 (23.8%) inbred animals. The study also included the determination of ancestral paths for the PRC population. The longest ancestral path (LAP) consisted of 12 generations (three animals) while only 229 animals (2.53%) had an LAP comprising at least 10 generations. Therefore, a need exists, particularly in PRC as a small local breed, to manage selection and mating decisions to control future coancestry and inbreeding, which would lead to better handling of the effective population size. The study results showed the possibility of disrupting the balance of the structure of a small population like PRC. Hence, endangered populations need to be monitored on a continuous basis.


Assuntos
Variação Genética , Endogamia , Animais , Bovinos , Linhagem , Polônia , Densidade Demográfica
2.
Antimicrob Agents Chemother ; 45(7): 2060-3, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11408223

RESUMO

The purpose of this investigation was to determine the serum pharmacokinetics, tissue distribution, and renal toxicity of amphotericin B (AmpB) following administration of a single intravenous dose (1 mg/kg of body weight) of Fungizone (FZ) and a heat-treated form of FZ (HFZ) to New Zealand White female rabbits. FZ solutions were heated at 70 degrees C for 20 min to produce HFZ. Blood samples were obtained before drug administration and serially thereafter. After collection of the 48-h blood sample, each rabbit was humanely sacrificed and the right kidney, spleen, lungs, liver, and heart were harvested for AmpB analysis. Serum creatinine levels were measured before and 10 h after drug administration. AmpB concentrations in the serum and tissues were analyzed using high-performance liquid chromatography. FZ administration to rabbits resulted in a greater-than-50% increase in serum creatinine concentrations compared to baseline. However, HFZ administration resulted in no difference in serum creatinine concentrations compared to baseline. The AmpB area under the concentration-time curve (AUC) after HFZ administration was significantly lower than the AmpB AUC in rabbits administered FZ. However, AmpB systemic total body clearance was significantly greater in rabbits administered HFZ than in rabbits administered FZ without any differences in volume of distribution at steady state. Kidney tissue AmpB concentrations, although not significantly different, were greater in rabbits administered FZ than in rabbits administered HFZ. Likewise, lung and spleen AmpB concentrations, although not significantly different, were greater in rabbits administered FZ than in rabbits administered HFZ. However, liver AmpB concentrations were significantly lower in rabbits administered FZ than in rabbits administered HFZ. No significant differences in heart AmpB concentration between rabbits administered FZ and those given HFZ were found. These findings suggest that the pharmacokinetics, tissue distribution, and renal toxicity of AmpB are modified following administration of HFZ. HFZ could be an improved low-cost AmpB drug delivery system that has a potentially higher therapeutic index than FZ.


Assuntos
Anfotericina B/sangue , Antifúngicos/sangue , Rim/efeitos dos fármacos , Anfotericina B/efeitos adversos , Anfotericina B/farmacocinética , Animais , Antifúngicos/efeitos adversos , Antifúngicos/farmacocinética , Área Sob a Curva , Feminino , Injeções Intravenosas , Rim/metabolismo , Coelhos , Distribuição Tecidual
4.
7.
Photochem Photobiol ; 65(1): 91-5, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9066288

RESUMO

Psoralens are a class of pharmaceutical agents commonly used to treat several cutaneous disorders. When irradiated with a mode-locked titanium: sapphire (Ti:sapphire) laser tuned to 730 nm, an aqueous solution of 4'-hydroxymethyl-4,5',8-trimethylpsoralen (HMT) emits blue light. The emission spectrum is centered at 452 nm and is identical to that obtained by one-photon excitation with UVA excitation, and its magnitude depends quadratically on the intensity of laser excitation. These results suggest that two-photon excitation occurs to a potentially photochemically active state. To estimate the two-photon absorption cross section, it was first necessary to measure the emission quantum yield of HMT using 365 nm excitation at room temperature that resulted in a value of 0.045 +/- 0.007. The two-photon absorption cross section of HMT at 730 nm is therefore estimated to be 20 x 10(-50) cm4 s (20 Göppert-Mayer). The excited-state photophysics and photochemistry of psoralens suggest potential applications to cutaneous phototherapy in diseases such as psoriasis and dystrophic epidermolysis bullosa.


Assuntos
Trioxsaleno/análogos & derivados , Óxido de Alumínio , Lasers , Rodaminas , Espectrofotometria Atômica , Trioxsaleno/química
9.
J Invest Dermatol ; 105(5): 648-52, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7594636

RESUMO

Herlitz junctional epidermolysis bullosa is an autosomal recessive disorder characterized by generalized blistering at the lamina lucida of the cutaneous basement membrane. The monoclonal antibody GB3 has been used as a diagnostic probe because of its lack of reactivity in patient skin. The antigen recognized by GB3 has been identified as laminin-5, a glycoprotein consisting of three subunits (alpha 3, beta 3 and gamma 2). To identify the laminin-5 protein chain that contains the epitope recognized by GB3 and to determine if chain assembly is required for antibody recognition, we expressed a gamma 2 protein constructed from a full-length gamma 2 cDNA. Radioimmunoprecipitation of the culture medium from 293 cells revealed that both GB3 and anti-gamma 2 polyclonal antibodies were capable of directly precipitating recombinant gamma 2 without coprecipitation of other proteins. In immunodepletion experiments, each antibody removed most of the protein that was reactive with the other antibody. The epitope recognized by GB3 is present only when the complex is in the native conformation because GB3 reacted only with the non-reduced laminin-5, but not the reduced laminin-5 in immunoblots. Moreover, because GB3 reacted with laminin-5 of SCC25 cells (gamma 2 in the heterotrimer) but not recombinant gamma 2 in 293 cells (gamma 2 alone) during indirect immunofluorescence staining, this epitope may be dependent upon a less stable conformation of gamma 2. We conclude that GB3 recognizes the gamma 2 chain of laminin-5 and that the epitope is entirely contained in the native form of the gamma 2 chain.


Assuntos
Moléculas de Adesão Celular/química , Epidermólise Bolhosa/imunologia , Cadeias gama de Imunoglobulina/imunologia , Anticorpos Monoclonais , Moléculas de Adesão Celular/genética , Sondas de DNA/análise , Epidermólise Bolhosa/diagnóstico , Epitopos/imunologia , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Immunoblotting , Cadeias gama de Imunoglobulina/química , Imuno-Histoquímica , Pele/química , Calinina
10.
J Biol Chem ; 270(40): 23496-503, 1995 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-7559513

RESUMO

Laminin-5 is a heterotrimer composed of alpha 3, beta 3, and gamma 2 chains, produced by keratinocytes and the human squamous cell carcinoma line (SCC-25), and is one of the candidate proteins for the genetic lesion in junctional epidermolysis bullosa. Two-dimensional SDS-polyacrylamide gel electrophoresis (first dimension, nonreducing conditions; second dimension, reducing conditions) revealed that the immunoprecipitated laminin-5 from a SCC-25 cell fraction consisted of alpha 3, beta 3, and gamma 2 monomers, a beta 3 gamma 2 heterodimer, and an alpha 3 beta 3 gamma 2 heterotrimer. The presence of the beta 3 gamma 2 heterodimer, but not heterodimers containing an alpha 3 chain and any of the other chains, was suggestive of assembly of laminin-5 proceeding from a beta 3 gamma 2 heterodimer to an alpha 3 beta 3 gamma 2 heterotrimer. We showed, by cotransfection experiments using full-length recombinant beta 3 and gamma 2 chains in a human cell line devoid of endogenous laminin-5, that stable heterodimers can be formed in the absence of alpha 3 chain expression. In the SCC-25 cell fraction, the alpha 3 monomer pool was the smallest of the monomers. Pulse-chase experiments using the cell fraction also indicated that the heterotrimer was assembled after a 10-min pulse and was nearly absent after a 24-h chase. These results are consistent with the synthesis of alpha 3 being limiting for heterotrimer assembly, with rapid association of the alpha 3 chain with beta 3 gamma 2 heterodimers to form complete heterotrimers. Treatment with tunicamycin reduced the size of each of the laminin-5 subunits, indicating that all chains are glycosylated, but that N-linked glycosylation is not necessary for chain assembly and secretion.


Assuntos
Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Epidermólise Bolhosa Juncional/genética , Epidermólise Bolhosa Juncional/metabolismo , Glicosilação , Humanos , Queratinócitos/metabolismo , Cinética , Modelos Biológicos , Peso Molecular , Conformação Proteica , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células Tumorais Cultivadas , Tunicamicina/farmacologia , Calinina
11.
FASEB J ; 9(13): 1371-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7557028

RESUMO

Type I collagenase plays an important role in both tumor metastasis and the remodeling of connective tissue in normal human skin, during wound healing, for example, and may participate in the pathophysiology of some dermatological diseases such as skin cancer and a chronic blistering disease, recessive dystrophic epidermolysis bullosa. In an effort specifically to inhibit collagenase expression, we have designed phosphorothioate antisense oligonucleotides, linked at the 5' ends with photoreactive 4'-(hydroxyethoxymethyl)-4,5',8-trimethyl-psoralen (HMT), and directed them against the 5' end of the collagenase mRNA. Two antisense-HMT molecules targeting a region overlapping the initiation codon were compared. Only one contained the HMT moiety targeting a 5'TpA on its complementary sense strand, and we observed greater than 50-fold improvement on the cross-linking of this antisense oligonucleotide to its target sequence after ultraviolet A (UVA) irradiation. Likewise, sequence complementary to the 5'TpA target was also required to demonstrate specific inhibition of in vitro translation of collagenase mRNA. Tissue culture experiments, conducted by incubation of collagenase-specific antisense-HMT oligonucleotides with fibroblasts in monolayer or in 3-dimensional dermal equivalents, showed lowered collagenase levels 24 h after UVA irradiation as compared to controls. Initial screening of antisense oligomers for specific hybridization and photo-cross-linking is a useful step in the design of antisense oligonucleotides, and allowed us to design an HMT-linked antisense phosphorothioate oligonucleotide that specifically inhibits the expression of fibroblastic collagenase.


Assuntos
Colagenases/genética , Reagentes de Ligações Cruzadas/administração & dosagem , Furocumarinas/administração & dosagem , Oligonucleotídeos Antissenso/química , Sequência de Bases , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Humanos , Metaloproteinase 1 da Matriz , Dados de Sequência Molecular , Oligonucleotídeos Antissenso/administração & dosagem , Fotoquímica , Biossíntese de Proteínas/efeitos dos fármacos , Raios Ultravioleta
12.
Br J Dermatol ; 132(5): 725-9, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7772477

RESUMO

We have previously identified a novel 105-kDa lower lamina lucida protein detected by the autoantibodies from a group of patients who developed a unique immune-mediated subepidermal bullous dermatosis. We sought to determine if this novel basement membrane zone (BMZ) protein is normally expressed in the skin of patients with various subsets of epidermolysis bullosa (EB). Indirect immunofluorescence microscopy performed on non-lesional skin sections from patients with three major EB subsets revealed absence or significantly reduced expression of this novel BMZ protein in 20 out of 23 skin sections from patients with generalized dominant and recessive dystrophic EB. However, immunoblot analyses with the autoantibodies on Western-blotted proteins revealed that a comigrating 105-kDa protein is present in both cytosol extracts (n = 6) and conditioned media (n = 3) of cultured dermal fibroblasts derived from patients with dystrophic EB, as well as those cultured from two healthy individuals. Although the reason for such disparate findings is not known, the defective in vivo expression of this novel 105-kDa protein in dystrophic EB is presumably not due to a failure of fibroblasts to synthesize or secrete the protein. It is possible, however, that the 105-kDa protein may be unable to incorporate into the BMZ because it is produced in a dysfunctional form, or its BMZ binding site is missing. It is also possible that other structural alterations in skin BMZ, which occur in dystrophic EB, result in masking of the antigenic binding by the autoantibody when intact BMZ is probed.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Epidermólise Bolhosa Distrófica/metabolismo , Proteínas de Membrana/biossíntese , Adulto , Autoanticorpos , Membrana Basal/metabolismo , Western Blotting , Linhagem Celular , Fibroblastos/metabolismo , Humanos , Proteínas de Membrana/química , Microscopia de Fluorescência , Peso Molecular
13.
Arthritis Rheum ; 38(3): 351-60, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7880189

RESUMO

OBJECTIVE: To develop guidelines for therapeutic trials designed to improve the overall course of systemic sclerosis (SSc), that is, to reduce the development of significant organ damage or death. METHODS: A committee developed general guidelines for patient inclusion and exclusion criteria, randomization, blinding of patients and physicians, controls, duration of the trial, investigator training, responses, samples size, study dropouts, statistical analyses, data management, and safety monitoring. Delphi and nominal group techniques were used. RESULTS: Briefly, patients with diffuse cutaneous SSc of less than 24 months' duration should be included because they are at greatest risk for the development of severe organ damage and death. Patients should be excluded if they have other connective tissue diseases, SSc-like illnesses related to exposures or ingestions, severe existing internal organ damage, an unacceptable risk of side effects, or concurrent therapies that might independently influence the outcome. Randomized, double-blind, placebo-controlled trials are preferred. The treatment and followup period must be long enough to permit observation of any disease modification, which is likely to require 18-36 months, unless an extraordinarily effective therapy is identified. Responses selected should be quantitative, consistently and accurately reflect activity of SSc in major target organs (not solely the skin), be sensitive to change, and be standardized, with limited variability. An example of a set of responses is given. Surrogate responses are desirable, but none have been validated as correlating with organ damage. CONCLUSION: Guidelines have been established for trials of disease-modifying interventions in SSc. These guidelines will need to be altered as additional information becomes available. Any given protocol will be individualized based on the nature of the intervention and objectives of the study. Nonetheless, each study team should develop a protocol that meets the spirit of these guidelines.


Assuntos
Ensaios Clínicos como Assunto/métodos , Projetos de Pesquisa , Escleroderma Sistêmico/tratamento farmacológico , Protocolos Clínicos , Ensaios Clínicos como Assunto/normas , Ensaios Clínicos Fase I como Assunto/métodos , Ensaios Clínicos Fase II como Assunto/métodos , Interpretação Estatística de Dados , Relação Dose-Resposta a Droga , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Projetos de Pesquisa/normas , Escleroderma Sistêmico/mortalidade , Análise de Sobrevida , Resultado do Tratamento
14.
J Invest Dermatol ; 102(6): 951-7, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7516399

RESUMO

Type I human skin collagenase (HSC-1) was localized in developing embryonic and fetal skin ranging from 6 to 20 weeks estimated gestational age using an antigen-specific, affinity-purified, polyclonal antiserum to HSC-1 and an avidin-biotin alkaline phosphatase procedure. Double immunolabeling with monoclonal antibodies for Factor VIII-related antigen, type IV collagen, and the 68-kilodalton neurofilament subunit was performed using a direct peroxidase procedure. By 8 weeks estimated gestational age, HSC-1 localized to the periderm, the basal cell epidermal keratinocytes, dermal fibroblasts, and surrounding extracellular matrix. At 12 weeks estimated gestational age, HSC-1 immunolabeling showed a continued association with the epidermis and dermis. Dermal and subcutaneous blood vessels and the surrounding extracellular matrix were positive for HSC-1 labeling. HSC-1 staining was also found around developing nerves and in association with dermal fibroblasts. In the developing hair follicle, HSC-1 was present in keratinocytes of the pre-germ, germ, hair peg, and bulbous hair peg. HSC-1 immunoreactivity was also found in association with the hair canal, the bulge, and the dermal papillae, but was absent from the fetal sebaceous gland. These data demonstrate the association of HSC-1 with the development of interfollicular epidermis, the dermal collagenous matrix, the process of angiogenesis, the development of nerves, and hair follicle morphogenesis.


Assuntos
Colagenases/análise , Feto/enzimologia , Pele/embriologia , Pele/enzimologia , Anticorpos Monoclonais , Western Blotting , Células Cultivadas , Colágeno/análise , Colágeno/imunologia , Colagenases/fisiologia , Desenvolvimento Embrionário e Fetal , Matriz Extracelular/enzimologia , Feto/citologia , Fibroblastos/citologia , Fibroblastos/enzimologia , Cabelo/embriologia , Humanos , Imuno-Histoquímica , Queratinócitos/citologia , Queratinócitos/enzimologia , Morfogênese , Neovascularização Patológica , Sistema Nervoso/embriologia , Proteínas de Neurofilamentos/análise , Proteínas de Neurofilamentos/imunologia , Pele/citologia , Fator de von Willebrand/análise , Fator de von Willebrand/imunologia
15.
Genomics ; 21(1): 160-8, 1994 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8088783

RESUMO

Epidermolysis bullosa (EB) is a group of heritable mechano-bullous skin diseases classified into three major categories on the basis of the level of tissue separation within the dermal-epidermal basement membrane zone. The most severe, dystrophic (scarring) forms of EB demonstrate blister formation below the cutaneous basement membrane at the level of the anchoring fibrils. Ultrastructural observations of altered anchoring fibrils and genetic linkage to the gene encoding type VII collagen (COL7A1), the major component of anchoring fibrils, have implicated COL7A1 as the candidate gene in the dystrophic forms of EB. We have recently cloned the entire cDNA and gene for human COL7A1, which has been mapped to 3p21. In this study, we describe mutations in four COL7A1 alleles in three patients with severe, mutilating recessive dystrophic EB (Hallopeau-Siemens type, HS-RDEB). Each of these mutations resulted in a premature termination codon (PTC) in the amino-terminal portion of COL7A1. One of the patients was a compound heterozygote for two different mutations. The heterozygous carriers showed an approximately 50% reduction in anchoring fibrils, yet were clinically unaffected. Premature termination codons in both alleles of COL7A1 may thus be a major underlying cause of the severe, recessive dystrophic forms of EB.


Assuntos
Códon , Colágeno/genética , Epidermólise Bolhosa Distrófica/genética , Regiões Terminadoras Genéticas , Adulto , Alelos , Sequência de Bases , Análise Mutacional de DNA , Epidermólise Bolhosa Distrófica/patologia , Feminino , Genes Recessivos , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase , Transcrição Gênica
16.
Exp Cell Res ; 211(2): 212-8, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8143767

RESUMO

Recessive dystrophic epidermolysis bullosa (RDEB) is a mutilating disease of the skin characterized by recurrent blistering and erosions that result from compromised integrity of the basement membrane zone. In this study, fibroblasts derived from the skin of RDEB patients were characterized for expression of the major metalloproteinases, particularly interstitial collagenase. Consistent with previous reports on increased collagenase protein levels in fibroblasts from some RDEB patients, we found that steady-state levels of collagenase mRNA were significantly increased in fibroblast strains derived from three of five RDEB patients compared to fibroblasts obtained from normal donors. Stromelysin mRNA was elevated in the same three fibroblast strains, whereas expression of neither the 72- nor the 92-kDa type IV collagenases was different from that of controls. Tissue inhibitor of metalloproteinases was expressed in RDEB fibroblasts at levels similar to those observed in normal fibroblasts. To investigate the mechanism behind the steady-state elevation in collagenase and stromelysin expression, AP-1 expression and activation were studied. Although levels of Jun expression were not different from those seen in normal fibroblasts, AP-1 activity, as assessed by ability to bind to a TPA response element-containing oligonucleotide, was endogenously elevated in RDEB fibroblasts compared to normal fibroblasts. Transfection studies using a plasmid construct containing the collagenase promoter linked to a CAT reporter gene demonstrated that RDEB fibroblasts were able to support active transcription of the promoter compared to normal fibroblasts. These studies support the hypothesis that RDEB fibroblasts contain chronically activated AP-1, and perhaps other transactivating factors, that contribute to the cellular phenotype of collagenase and stromelysin overexpression.


Assuntos
Colagenases/genética , Epidermólise Bolhosa Distrófica/genética , Epidermólise Bolhosa Distrófica/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-jun/metabolismo , Células Cultivadas , Colagenases/metabolismo , Epidermólise Bolhosa Distrófica/etiologia , Regulação da Expressão Gênica , Genes Recessivos , Humanos , Metaloproteinase 3 da Matriz , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima
17.
Nucleic Acids Res ; 22(7): 1305-12, 1994 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-8165146

RESUMO

C-Jun is a cellular transcription factor that can control gene expression in response to treatment of cells with phorbol esters, growth factors, and expression of some oncogenes. The ability of c-Jun to catalyze the transcription of certain genes is controlled, in part, by changes in the phosphorylation state of specific amino acids in c-Jun. One of the major sites that is phosphorylated during signal response is Ser73. Here we show that substitution of a negatively charged aspartic acid residue at 73 constitutively increased transcriptional activity of c-Jun. The Asp73 substitution also enhanced its availability to bind to DNA in a whole cell extract without altering its intrinsic DNA binding activity since the intrinsic activity was unaltered for the c-Jun mutant proteins expressed in a bacterial system. The negatively charged Asp substitution may mimic the negative charge of a phosphorylated serine at 73. The substitution of an uncharged alanine at 73 resulted in lowered activities. The N-terminal end of c-Jun containing these substitutions was fused to the DNA-binding region of the bovine papilloma virus E2 protein, and was able to confer the same activation properties to the fusion protein at the heterologous E2 DNA-binding site. Ser73 lies in a region of c-Jun previously proposed to bind an uncharacterized inhibitor, perhaps related to a protein of approximately 17.5 kD that coprecipitates along with our c-Jun or the JunE2 fusion products.


Assuntos
Regulação da Expressão Gênica , Proteínas Proto-Oncogênicas c-jun/metabolismo , Sequência de Aminoácidos , Ácido Aspártico/metabolismo , Sequência de Bases , Linhagem Celular , DNA , Eletroquímica , Células HeLa , Humanos , Dados de Sequência Molecular , Mutação , Proteínas Proto-Oncogênicas c-jun/química , Serina/metabolismo , Transcrição Gênica
18.
Arch Dermatol Res ; 287(1): 107-14, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7726628

RESUMO

Cell-matrix interactions have an important impact on regulating connective tissue degradation during physiological and pathological processes, e.g., development, wound healing and tissue remodeling and tumor invasion and metastasis. Connective tissue breakdown is initiated by a specific class of enzymes, the matrix metalloproteinases, which include the type I collagenases, the type IV collagenases/gelatinases and the stromelysins and which vary with respect to their substrate specificities. The activity of the metalloproteinases is regulated by de novo synthesis of the proenzymes, the activation of the zymogens and by the presence of the inhibitors, TIMPs. This tight control is required in order to guarantee normal functioning of connective tissue.


Assuntos
Tecido Conjuntivo/metabolismo , Matriz Extracelular/enzimologia , Metaloendopeptidases/biossíntese , Dermatopatias/metabolismo , Animais , Colágeno/biossíntese , Tecido Conjuntivo/patologia , Matriz Extracelular/fisiologia , Humanos , Dermatopatias/patologia
19.
J Invest Dermatol ; 101(3): 280-5, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8370965

RESUMO

The reproductive hormone, relaxin, inhibits collagen synthesis in vitro by normal human dermal fibroblast. In the present study, recombinant human relaxin is shown to modulate collagen accumulation and organization by mesenchymal cells in vivo in two rodent models of fibrosis: 1) fibrotic infiltration of polyvinyl alcohol sponge implants in rats, and 2) capsule formation around implanted osmotic pumps in mice. In the sponge, relaxin inhibits collagen accumulation, a measured by hydroxyproline content, in a dose-responsive manner by up to 25-29% in animals receiving 30 ng/ml relaxin, a finding supported by a decrease in collagen-specific trichrome staining in sections of sponges from relaxin-treated animals. In mice, the capsules surrounding relaxin-containing pumps are thinner and less dense than are capsules from control pumps. Ultrastructurally, control capsules are composed of densely packed parallel arrays of collagen fibrils, whereas fibrils more frequently are not packed in parallel arrays and are less abundant in treated capsules.


Assuntos
Colágeno/biossíntese , Relaxina/farmacologia , Animais , Modelos Animais de Doenças , Feminino , Fibrose/metabolismo , Esponja de Gelatina Absorvível/química , Humanos , Hidroxiprolina/análise , Camundongos , Camundongos Endogâmicos BALB C , Álcool de Polivinil , Ratos , Ratos Sprague-Dawley , Relaxina/sangue
20.
J Dermatol Sci ; 5(2): 97-103, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8357788

RESUMO

A variety of methods were used to fracture the dermal-epidermal junction (DEJ) of human skin. These included warm and hot phosphate buffered saline, trypsin, cold 1 M salt, potassium bromide and proteolytic digestion with dispase. The localization and sensitivity of basement membrane components (bullous pemphigoid antigen, BM 600/nicein, epiligrin, kalinin, laminin, collagens IV and VII (EBA antigen) and linkin) were determined after the DEJ was fractured by each method. We found that the basement membrane zone proteins, BM 600/nicein, epiligrin and kalinin remained with the dermal side of the DEJ fractured through the lamina lucida by cold salt, phosphate buffered saline and potassium bromide. BM 600/nicein, epiligrin and kalinin were not detected after treatment with trypsin. In contrast, laminin, another glycoprotein in the lamina lucida, was insensitive to all of the procedures, but co-localized to the dermal side of DEJ-fractured skin. We also found that separation of the DEJ with brief exposure of skin to 56 degrees C provided a useful substrate for testing the autoantibodies in the sera of patients with epidermolysis bullosa acquisita (EBA). Heat-separated skin can be prepared in a significantly shorter period of time than salt-separated skin.


Assuntos
Anticorpos/análise , Proteínas de Transporte , Moléculas de Adesão Celular/análise , Proteínas do Citoesqueleto , Proteínas do Tecido Nervoso , Colágenos não Fibrilares , Pele/química , Anticorpos/imunologia , Autoantígenos/análise , Autoantígenos/imunologia , Membrana Basal/química , Moléculas de Adesão Celular/imunologia , Colágeno/análise , Colágeno/imunologia , Distonina , Imunofluorescência , Humanos , Laminina/análise , Laminina/imunologia , Calinina , Colágeno Tipo XVII
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