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1.
Cochrane Database Syst Rev ; (1): CD003816, 2005 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-15674916

RESUMO

BACKGROUND: Human insulin was introduced for the routine treatment of diabetes mellitus in the early 1980s without adequate comparison of efficacy to animal insulin preparations. First reports of altered hypoglycaemia awareness after transfer to human insulin made physicians and especially patients uncertain about potential adverse effects of human insulin. OBJECTIVES: To assess the effects of different insulin species by evaluating their efficacy (in particular glycaemic control) and adverse effects profile (mainly hypoglycaemia). SEARCH STRATEGY: A highly sensitive search for randomised controlled trials combined with key terms for identifying studies on human versus animal insulin was performed using The Cochrane Library, MEDLINE and EMBASE. We also searched reference lists and databases of ongoing trials. Date of latest search: July 2004. SELECTION CRITERIA: We included randomised controlled clinical trials with diabetic patients of all ages that compared human to animal (for the most part purified porcine) insulin. Trial duration had to be at least one month in order to achieve reliable results on the main outcome parameter glycated haemoglobin. DATA COLLECTION AND ANALYSIS: Trial selection as well as evaluation of study quality was performed by two independent reviewers. The quality of reporting of each trial was assessed according to a modification of the quality criteria as specified by Schulz and by Jadad. MAIN RESULTS: Altogether 2156 participants took part in the 45 randomised controlled studies that were discovered through extensive search efforts. Though many studies had a randomised, double-blind design, most studies were of poor methodological quality. Purified porcine and semi-synthetic insulin were most often investigated. No significant differences in metabolic control or hypoglycaemic episodes between various insulin species could be elucidated. Insulin dose and insulin antibodies did not show relevant dissimilarities. AUTHORS' CONCLUSIONS: A comparison of the effects of human and animal insulin as well as of the adverse reaction profile did not show clinically relevant differences. Many patient-oriented outcomes like health-related quality of life or diabetes complications and mortality were never investigated in high-quality randomised clinical trials. The story of the introduction of human insulin might be repeated by contemporary launching campaigns to introduce pharmaceutical and technological innovations that are not backed up by sufficient proof of their advantages and safety.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Animais , Humanos , Hipoglicemiantes/efeitos adversos , Insulina/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Especificidade da Espécie
2.
Cochrane Database Syst Rev ; (3): CD003816, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12917989

RESUMO

BACKGROUND: Human insulin was introduced for the routine treatment of diabetes mellitus in the early 1980s without adequate comparison of efficacy to animal insulin preparations. First reports of altered hypoglycaemia awareness after transfer to human insulin made physicians and especially patients uncertain about potential adverse effects of human insulin. OBJECTIVES: To assess the effects of different insulin species by evaluating their efficacy (in particular glycaemic control) and adverse effects profile (mainly hypoglycaemia). SEARCH STRATEGY: A highly sensitive search for randomised controlled trials combined with key terms for identifying studies on human versus animal insulin was performed using the Cochrane Library (issue 2, 2002), Medline (1966 to May, 2002) and Embase (1974 to February, 2002). We also searched reference lists and databases of ongoing trials. Date of latest search: May 2002. SELECTION CRITERIA: We included randomised controlled clinical trials with diabetic patients of all ages that compared human to animal (for the most part purified porcine) insulin. Trial duration had to be at least one month in order to achieve reliable results on the main outcome parameter glycated haemoglobin. DATA COLLECTION AND ANALYSIS: Trial selection as well as evaluation of study quality was performed by two independent reviewers. The quality of reporting of each trial was assessed according to a modification of the quality criteria as specified by Schulz and by Jadad. MAIN RESULTS: Altogether 2156 participants took part in the 45 randomised controlled studies that were discovered through extensive search efforts. Though many studies had a randomised, double-blind design, most studies were of poor methodological quality. Purified porcine and semi-synthetic insulin were most often investigated. No significant differences in metabolic control or hypoglycaemic episodes between various insulin species could be elucidated. Insulin dose and insulin antibodies did not show relevant dissimilarities. REVIEWER'S CONCLUSIONS: A comparison of the effects of human and animal insulin as well as of the adverse reaction profile did not show clinically relevant differences. Many patient-oriented outcomes like health-related quality of life or diabetes complications and mortality were never investigated in high-quality randomised clinical trials. The story of the introduction of human insulin might be repeated by contemporary launching campaigns to introduce pharmaceutical and technological innovations that are not backed up by sufficient proof of their advantages and safety.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Animais , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Especificidade da Espécie
3.
Cochrane Database Syst Rev ; (3): CD003816, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12137720

RESUMO

BACKGROUND: Human insulin was introduced for the routine treatment of diabetes mellitus in the early 1980s without adequate comparison of efficacy to animal insulin preparations. First reports of altered hypoglycaemia awareness after transfer to human insulin made physicians and especially patients uncertain about potential adverse effects of human insulin. OBJECTIVES: To assess the effects of different insulin species by evaluating their efficacy (in particular glycaemic control) and adverse effects profile (mainly hypoglycaemia). SEARCH STRATEGY: A highly sensitive search for randomised controlled trials combined with key terms for identifying studies on human versus animal insulin was performed using the Cochrane Library (issue 2, 2002), Medline (1966 to May, 2002) and Embase (1974 to February, 2002). We also searched reference lists and databases of ongoing trials. Date of latest search: May 2002. SELECTION CRITERIA: We included randomised controlled clinical trials with diabetic patients of all ages that compared human to animal (for the most part purified porcine) insulin. Trial duration had to be at least one month in order to achieve reliable results on the main outcome parameter glycated haemoglobin. DATA COLLECTION AND ANALYSIS: Trial selection as well as evaluation of study quality was performed by two independent reviewers. The quality of reporting of each trial was assessed according to a modification of the quality criteria as specified by Schulz and by Jadad. MAIN RESULTS: Altogether 2156 participants took part in the 45 randomised controlled studies that were discovered through extensive search efforts. Though many studies were of a randomised, double-blind design, most studies were of poor methodological quality. Purified porcine and semi-synthetic insulin were most often investigated. No significant differences in metabolic control or hypoglycaemic episodes between various insulin species could be elucidated. Insulin dose and insulin antibodies did not show relevant dissimilarities. REVIEWER'S CONCLUSIONS: A comparison of the effects of human and animal insulin as well as of the adverse reaction profile did not show clinically relevant differences. Many patient-oriented outcomes like health-related quality of life or diabetes complications and mortality were never investigated in high-quality randomised clinical trials. The story of the introduction of human might be repeated by contemporary launching campaigns to introduce pharmaceutical and technological innovations that are not backed up by sufficient proof of their advantages and safety.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Animais , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Especificidade da Espécie
4.
AJR Am J Roentgenol ; 177(2): 421-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11461874

RESUMO

OBJECTIVE: Patients with glycogen storage disease type IB have neutropenia and neutrophil dysfunction that predispose them to frequent infections, for which they are given granulocyte colony--stimulating factor. Because neutropenia is a consequence of defects in myeloid maturation, the bone marrow aspirations show hypercellularity due to myeloid hyperplasia. This study evaluated MR imaging of bone marrow in glycogen storage disease type IB with and without granulocyte colony-stimulating factor. CONCLUSION: As confirmed by the histologic results in bone marrow aspirations, abnormal findings on MR images of bone marrow in patients with glycogen storage disease type IB indicate an increased myelopoietic activity, which is augmented by treatment with granulocyte colony-stimulating factor.


Assuntos
Medula Óssea/patologia , Doença de Depósito de Glicogênio Tipo I/patologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Feminino , Doença de Depósito de Glicogênio Tipo I/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Leucopoese , Masculino , Neutrófilos , Fatores de Tempo
5.
Z Arztl Fortbild Qualitatssich ; 95(2): 95-104, 2001 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-11268884

RESUMO

The proportion of evidence-based health care gives rise to controversy. Estimates range from 4%-20%. Studies trying to ascertain the proportion of evidence-based healthcare show wide variations in the results depending on design, setting, subject, main outcome measures, methodology and definition of evidence from 11-82%. The results should not be generalized to community health care and should not be misused in public discussions.


Assuntos
Atenção à Saúde/normas , Medicina Baseada em Evidências , Pesquisa/tendências , Humanos , Garantia da Qualidade dos Cuidados de Saúde
6.
Rofo ; 173(2): 121-5, 2001 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-11253083

RESUMO

PURPOSE: Recurrent infections in patients with glycogen storage disease (GSD) type Ib resulting from an associated neutropenia are frequently treated with granulocyte colony-stimulating factors (G-CSF). The aim of this study was to evaluate the changes occurring in bone marrow by magnetic resonance imaging (MRI) in these patients. MATERIAL AND METHODS: The distal femoral and tibial bones of six patients with GSD Ib were evaluated by MRI. Four of these patients were treated with G-CSF for at least 3.9 to a maximum of 8.2 years (mean 5.8 years). The imaging sequences encompassed spin-echo as well as short-time inversion recovery sequences. 4 of the 6 patients had bone marrow aspirations. RESULTS: The patients who had undergone therapy with G-CSF showed a marked increase in signal strength in STIR sequences which encompassed the entire medullar cavity. In T1-weighted images these areas were hypointense. Biopsies obtained from these patients showed a bone marrow hypercellularity. The patients without G-CSF therapy showed the same signal intensity changes but with a more discrete and localized pattern in the metaphyseal cavities. CONCLUSION: In subjects with GSD Ib, an increased myelopoetic activity of the bone marrow which is intensified under long-term treatment with G-CSF can be demonstrated by MRI.


Assuntos
Medula Óssea/patologia , Doença de Depósito de Glicogênio Tipo I/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Imageamento por Ressonância Magnética , Adolescente , Adulto , Medula Óssea/efeitos dos fármacos , Feminino , Fêmur , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Humanos , Masculino , Proteínas Recombinantes , Tíbia , Fatores de Tempo
7.
Biol Cell ; 89(2): 123-31, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9351192

RESUMO

The imino sugar N-butyldeoxynojirimycin inhibits the N-linked oligosaccharide processing enzymes alpha-glucosidases I and II, and the ceramide specific glucosyltransferase which catalyses the first step in glucosphingolipid biosynthesis. We have studied the effects of this compound on the ultrastructure of HL-60 cells to identify novel activities of this compound. Treatment of HL-60 cells with this imino sugar results in several morphological changes within the cell, none of which result in cytotoxicity. The plasma membrane stains heavily with potassium ferrocyanide within 30 min following addition of the compound to the medium, and there is then a time dependent involvement of all other intracellular membranes. Secretory granules become enlarged and lose their dense core morphology and appear either empty and vacuolated or have low density contents. However, the most striking effect of NB-DNJ treatment is on the Golgi apparatus. The Golgi exhibits a time-dependent change from typical Golgi morphology to a structure almost completely devoid of cisternae and consisting predominantly of vesicles. All the observed changes are fully reversible on withdrawal of the compound.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Grânulos Citoplasmáticos/efeitos dos fármacos , Complexo de Golgi/efeitos dos fármacos , 1-Desoxinojirimicina/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Inibidores Enzimáticos/farmacologia , Glucosiltransferases/antagonistas & inibidores , Inibidores de Glicosídeo Hidrolases , Complexo de Golgi/ultraestrutura , Células HL-60 , Humanos , Cinética , Microscopia Eletrônica
8.
Science ; 276(5311): 428-31, 1997 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-9103204

RESUMO

The glycosphingolipid (GSL) lysosomal storage diseases result from the inheritance of defects in the genes encoding the enzymes required for catabolism of GSLs within lysosomes. A strategy for the treatment of these diseases, based on an inhibitor of GSL biosynthesis N-butyldeoxynojirimycin, was evaluated in a mouse model of Tay-Sachs disease. When Tay-Sachs mice were treated with N-butyldeoxynojirimycin, the accumulation of GM2 in the brain was prevented, with the number of storage neurons and the quantity of ganglioside stored per cell markedly reduced. Thus, limiting the biosynthesis of the substrate (GM2) for the defective enzyme (beta-hexosaminidase A) prevents GSL accumulation and the neuropathology associated with its lysosomal storage.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Encéfalo/metabolismo , Inibidores Enzimáticos/uso terapêutico , Gangliosídeo G(M2)/metabolismo , Lisossomos/metabolismo , Doença de Tay-Sachs/tratamento farmacológico , 1-Desoxinojirimicina/farmacocinética , 1-Desoxinojirimicina/uso terapêutico , Animais , Barreira Hematoencefálica , Modelos Animais de Doenças , Gangliosídeo G(M2)/biossíntese , Camundongos , Microscopia Eletrônica , Neurônios/metabolismo , Neurônios/ultraestrutura , Doença de Tay-Sachs/metabolismo
9.
J Virol ; 71(2): 988-95, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8995617

RESUMO

Null mutants and attenuated mutants of herpes simplex virus (HSV) have been shown to induce immunity against challenge from wild-type virus. Null viruses with a defect in late gene products would be expected to express more viral genes than viruses with defects in essential early gene products and thus induce a better immune response. Herpesviruses encode a late gene product (serine protease) that is autocatalytic and cleaves the capsid assembly protein during viral replication. To determine whether a virus with a mutation in this gene could induce immunity, we constructed a recombinant virus containing the gusA reporter gene in the protease domain of the HSV type 1 UL26 open reading frame (ORF). Consistent with previous results (M. Gao, L. Matusick-Kumar, W. Hurlburt, S. F. DiTusa, W. W. Newcomb, J. C. Brown, P. J. McCann, I. Deckman, and R. J. Colonno, J. Virol. 68:3702-3712, 1994), recombinant virus could be isolated only from helper cell lines expressing the product of the UL26 ORF. Mice inoculated with the recombinant virus were unaffected by doses of virus that were lethal to mice infected with wild-type virus. Mice which were previously inoculated with the recombinant virus were also protected by a subsequent challenge with wild-type virus in a dose-dependent manner. These results indicate that recombinant viruses lacking the protease gene are avirulent but render protection from subsequent challenge.


Assuntos
DNA Recombinante/imunologia , DNA Viral/genética , Infecções por Herpesviridae/imunologia , Serina Endopeptidases/genética , Simplexvirus/genética , Animais , Sequência de Bases , DNA Recombinante/administração & dosagem , Feminino , Deleção de Genes , Infecções por Herpesviridae/prevenção & controle , Camundongos , Dados de Sequência Molecular , Simplexvirus/imunologia
10.
J Biol Chem ; 269(43): 27108-14, 1994 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-7929454

RESUMO

We have previously reported that the imino sugar N-butyldeoxynojirimycin (NB-DNJ) inhibits glycolipid biosynthesis, in addition to its known activity as an inhibitor of the N-linked oligosaccharide processing enzyme alpha-glucosidase I. In an attempt to dissociate these two activities and identify an inhibitor which was more selective for the glycolipid biosynthetic pathway, several imino sugars have been N-alkylated and tested for inhibitory activity. The galactose analogue N-butyldeoxygalactonojirimycin (NB-DGJ) was found to be a potent inhibitor of glycolipid biosynthesis but in contrast to NB-DNJ had no effect on the maturation of N-linked oligosaccharides or on lysosomal glucocerebrosidase. The effect of increasing N-alkyl chain length on glycolipid inhibition was investigated. Nonalkylated DGJ, the N-methyl and N-ethyl derivatives, were noninhibitory. However, N-propylation resulted in partial inhibition while the N-butyl and N-hexyl derivatives resulted in maximal inhibition. Increasing alkyl chain length also resulted in increased potency of glucosyltransferase inhibition. In an in vitro Gaucher's disease model NB-DGJ was as effective as NB-DNJ in preventing glycolipid storage and may represent a more selective potential therapeutic agent than NB-DNJ for the management of this and other glycosphingolipidoses.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Glicolipídeos/biossíntese , Oligossacarídeos/biossíntese , 1-Desoxinojirimicina/farmacologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Doença de Gaucher/metabolismo , Glucosilceramidase/efeitos dos fármacos , Glucosiltransferases/antagonistas & inibidores , Humanos , Camundongos , Relação Estrutura-Atividade , alfa-Glucosidases/efeitos dos fármacos
11.
J Biol Chem ; 269(11): 8362-5, 1994 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-8132559

RESUMO

The imino sugar deoxynojirimycin and its alkylated derivatives are inhibitors of the N-linked oligosaccharide processing enzymes alpha-glucosidase I and II. These compounds are glucose analogues and have the potential to inhibit both glucosidases and glucosyltransferases. However, to date there has been no report of deoxynojirimycin or similar analogues inhibiting a mammalian glucosyltransferase. We have investigated the effects of deoxynojirimycin and its alkylated derivatives on the biosynthesis of glycolipids in HL-60 cells. We have found that the N-butyl and N-hexyl derivatives of deoxynojirimycin, but not deoxynojirimycin itself, are novel inhibitors of the glucosyltransferase-catalyzed biosynthesis of glucosylceramide. This results in the inhibition of biosynthesis of all glucosylceramide-based glycosphingolipids. We have investigated the ability of one of these compounds, N-butyldeoxynojirimycin, to offset glucosylceramide accumulation in an in vitro Gaucher's disease model. This compound prevents lysosomal glycolipid storage and offers a novel therapeutic approach for the management of this and other glycolipid storage disorders.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Glicolipídeos/biossíntese , Inibidores de Glicosídeo Hidrolases , 1-Desoxinojirimicina/farmacologia , Animais , Linhagem Celular , Doença de Gaucher , Glucosiltransferases/antagonistas & inibidores , Glicolipídeos/antagonistas & inibidores , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/ultraestrutura , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/ultraestrutura , Camundongos , Modelos Biológicos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
12.
Laryngoscope ; 103(5): 548-58, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8387129

RESUMO

Previous reports suggest that exogenous nerve growth factor (NGF) enhanced nerve regeneration in rabbit facial nerves. Rabbit facial nerve regeneration in 10-mm Silastic tubes prefilled with NGF was compared to cytochrome C (Cyt. C), bridging an 8-mm nerve gap. Three weeks following implantation, NGF-treated regenerates exhibited a more mature fascicular organization and more extensive neovascularization than cytochrome-C-treated controls. Morphometric analysis at the midtube of 3- and 5-week regenerates revealed no significant difference in the mean number of myelinated or unmyelinated axons between NGF- and cytochrome-C-treated implants. However, when the number of myelinated fibers in 5-week regenerates were compared to their respective preoperative controls, NGF-treated regenerates had recovered a significantly greater percentage of myelinated axons than cytochrome-C--treated implants (46% vs. 18%, respectively). In addition, NGF-containing chambers reinnervated a higher percentage of myelinated axons in the distal transected neural stumps (49% vs. 34%). Behavioral and electrophysiologic studies demonstrated spontaneous and induced activities in the target muscles when approximately one third of the myelinated axons were recovered in the midchamber (1280 axons). Horseradish peroxidase (HRP) studies demonstrated retrograde axonal transport to the midchamber and proximal transected neural stump. PC12 bioassay demonstrated persistent NGF activity in the intrachamber fluids at 3 (5:1 dilution) and 5 (2:1 dilution) weeks of entubation. Electrophysiologic tests demonstrated a slow conduction velocity of a propagated electrical impulse (43.5 m/s-1 vs. 67 m/s-1) and shallow wide compound action potential. In wider defects (15-mm chambers) and longer entubation periods (7 weeks), no regeneration or NGF activity was seen. Therefore, exogenous NGF provides an early but limited neurotrophic effect on the regeneration of the rabbit buccal division of the facial nerve and a limited behavioral and physiological improvement in the target muscles.


Assuntos
Nervo Facial/fisiologia , Fatores de Crescimento Neural/farmacologia , Regeneração Nervosa , Animais , Grupo dos Citocromos c/farmacologia , Nervo Facial/ultraestrutura , Feminino , Coelhos , Elastômeros de Silicone , Cloreto de Sódio
13.
Exp Neurol ; 119(2): 176-91, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8432358

RESUMO

The rat sciatic nerve does not possess a high potential for regeneration through silastic tubes when the interstump nerve gap is greater than 10 mm. In this study, the effect of NGF treatment on regeneration of the rat sciatic nerve in 10- and 15-mm silastic chambers was compared. In addition, regeneration in 15-mm silastic chambers was compared to regeneration in 15-mm semipermeable chambers. Sections of tubing were implanted and filled with NGF or a control solution of cytochrome C (Cyt. C). Tube implants were removed at various postoperative times and regeneration was assessed histologically and behaviorally. NGF treatment promoted regeneration success rate. It enhanced the initial outgrowth of nonneuronal cells and neuronal fibers into the chamber producing more cellular, organized regenerates. At 2 weeks, in 10-mm chambers, NGF-treated regenerates had fourfold more unmyelinated fibers than controls. At 3 weeks, NGF-treated regenerates possessed threefold more myelinated fibers than controls. After 4 weeks all regenerates had similar numbers of myelinated nerves at the chamber's midpoint. This initial "head start" was sustained peripherally as indicated by the earlier return of sensory function (response to a noxious temperature stimulus) in NGF-treated animals. Finally, regeneration success rate in 15-mm semipermeable tubes is greater than that in 15-mm silastic chambers (NGF and Cyt. C). However, regenerates in silastic chambers possessed twofold more myelinated fibers than regenerates in semipermeable chambers. The positive effects of NGF on neural regeneration and recovery of sensory function provide support for the potential use of NGF in treating peripheral nerve injuries.


Assuntos
Junções Intercelulares/fisiologia , Atividade Motora/fisiologia , Fatores de Crescimento Neural/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Nervo Isquiático/fisiologia , Sensação/fisiologia , Animais , Disponibilidade Biológica , Cultura em Câmaras de Difusão , Masculino , Atividade Motora/efeitos dos fármacos , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/fisiologia , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Fatores de Crescimento Neural/farmacocinética , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/citologia , Fatores de Tempo
14.
Arch Dermatol ; 125(2): 263-8, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2913963

RESUMO

Patients with xeroderma pigmentosum (XP) have more than a 1000-fold increased risk of cutaneous melanoma. To determine if the XP DNA repair defect is present in cutaneous pigmentary cells, nevus cells and melanocytes from four large, pigmented nevi were cultured from a 12-year-old girl with XP. Cultured melanocytes showed dendritic morphologic features, contained mature melanosomes, and reacted with monoclonal antibody to tyrosinase. Nevus cells were spindle shaped and expressed nevus cell-associated antigens. Melanocytes, nevus cells, and dermal fibroblasts from the patient with XP all had a similar reduction in DNA repair: unscheduled DNA synthesis was 30% to 50% of that in normal fibroblasts following a 30 J/m2 ultraviolet dose. After a 6 J/m2 ultraviolet dose, the proliferative ability of XP nevus cells and fibroblasts was reduced to 10% of that of normal fibroblasts. This study indicates that cultured melanocytes and nevus cells express the characteristic XP DNA repair defect.


Assuntos
Reparo do DNA , Melanócitos/ultraestrutura , Nevo/genética , Xeroderma Pigmentoso/genética , Sobrevivência Celular , Criança , Feminino , Fibroblastos/ultraestrutura , Humanos , Microscopia Eletrônica/métodos , Nevo/ultraestrutura , Células Tumorais Cultivadas
15.
J Invest Dermatol ; 86(4): 363-70, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2943821

RESUMO

Ultraviolet radiation of murine skin in vivo or epidermal cells (EC) in vitro dramatically inhibits the antigen-presenting capacity of EC in vitro and results in the inhibition of immune responses to antigen challenge. In humans, UV exposure in vivo markedly inhibits alloantigen presentation by EC in the EC-lymphocyte reaction (ELR) when EC are harvested immediately after the administration of 4 times the minimal erythema dose (4 MED), whereas EC harvested 72 h after 4 MED (UV-EC) exhibit enhanced allostimulatory capacity in the ELR. This enhanced ELR reactivity is due to the appearance, in the epidermis, of bone marrow-derived OKT6- DR+ cells which are distinct from Langerhans cells (LC) in their lack of surface OKT6 and in their ultrastructural morphology. This report focuses on the phenotype and function of T6- Dr+ UV-EC and on their relationship to known human antigen presenting cell (APC) subsets. Approximately 60% of T6- Dr+ UV-EC bore the monocyte marker defined by monoclonal antibody OKM5, but lacked determinants recognized by OKM1, Leu M1, Leu M3, Leu M4, Leu M5, and Mac1. All T6- Dr+ UV-EC bore the class II MHC antigen HLA-DQ (DC/DS), which is associated with a specialized subset of antigen-presenting monocytes capable of stimulation in the autologous mixed leukocyte reaction (AMLR). Panning of OKM5+ UV-EC resulted in a population of cells which was markedly enriched in melanophages and which exhibited potent alloantigen-presenting capacity in the ELR. Since OKM5+ T6- Dr+ UV-EC were similar to the specialized APC minor subset of OKM1- OKM5+ blood monocytes both in phenotype and in apparent phagocytic function, we examined other APC functions of UV-EC to assess the extent of this analogy. Relative to control EC (containing only LC as APC), UV-EC (containing functionally inactivated LC but many T6- Dr+ APC) induced significantly greater degrees of T-cell proliferation in the presence of either tetanus toxoid antigen or the mitogen concanavalin A. UV-EC, as well as panning-purified OKM5+ UV-EC, were also able to induce autologous T-cell proliferation in the absence of added antigen (autologous ELR), in contrast to control EC which were poor stimulators of an autologous ELR. Thus, although human EC 72 h after UV exposure are numerically and functionally depleted of LC, at least 2 additional subsets of T6- Dr+ APC appear in the epidermis.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Células Apresentadoras de Antígenos/efeitos da radiação , Antígenos de Superfície/análise , Melanócitos/efeitos da radiação , Monócitos/efeitos da radiação , Células Apresentadoras de Antígenos/classificação , Células Apresentadoras de Antígenos/imunologia , Antígenos de Diferenciação de Linfócitos T , Epiderme/imunologia , Antígenos HLA-DR , Antígenos de Histocompatibilidade Classe II , Humanos , Ativação Linfocitária/efeitos da radiação , Teste de Cultura Mista de Linfócitos , Melanócitos/classificação , Melanócitos/imunologia , Monócitos/classificação , Monócitos/imunologia , Fenótipo , Linfócitos T/imunologia , Raios Ultravioleta
16.
Am J Dermatopathol ; 7(2): 171-9, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3896008

RESUMO

Basic principles of production of monoclonal antibodies are discussed in this paper. In order to illustrate the usefulness of such production, studies of a new monoclonal antibody designated KF-2 which defines a unique cell-surface antigen found exclusively in the stratum spinosum of man and lower primates are recounted.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Superfície/imunologia , Epiderme/imunologia , Acantólise/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Antígenos de Superfície/análise , Sítios de Ligação de Anticorpos , Ligação Competitiva , Humanos , Técnicas Imunoenzimáticas , Microscopia Eletrônica , Primatas , Especificidade da Espécie
17.
J Invest Dermatol ; 84(2): 108-13, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2578528

RESUMO

In order to gain insight into the metabolism of keratin intermediate filaments (KIF) as well as the ability of KIF degradation products to interact with the immune system, we performed enzymatic degradation of purified KIF and examined their interaction with anti-KIF autoantibodies and their ability to act as immunogens. Aliquots of KIF aggregates were exposed to 3 different enzymes, that is, alpha-chymotrypsin, plasmin, and trypsin, in dose- and time-dependent experiments. The effect of the digestion was monitored sequentially by polyacrylamide gel electrophoresis and simultaneously by transmission electron microscopy. Furthermore, the KIF degradation proteins were then examined for their ability to bind anti-KIF autoantibodies by immunoblot and for their immunogenicity. In addition, preincubation of KIF with anti-KIF autoantibodies prior to the digestion procedure was performed to investigate a possible protective effect of this treatment against proteolytic degradation. The experiments demonstrated that: (1) KIF are degraded by serine proteinases, (2) with prolonged incubation time intact KIF are progressively replaced by more granular-amorphous material in transmission electron microscopy, (3) anti-KIF autoantibodies bind to KIF degradation proteins, (4) preincubation of KIF with anti-KIF autoantibodies does not exert any major protective effect for KIF against proteolytic degradation, and (5) the enzymatic degradation products of KIF can function as effective immunogens causing the formation of high-titer anti-KIF antibodies.


Assuntos
Proteínas de Filamentos Intermediários/imunologia , Queratinas/metabolismo , Autoanticorpos/imunologia , Quimotripsina/metabolismo , Eletroforese em Gel de Poliacrilamida , Endopeptidases/metabolismo , Fibrinolisina/metabolismo , Humanos , Técnicas Imunológicas , Proteínas de Filamentos Intermediários/metabolismo , Microscopia Eletrônica , Serina Endopeptidases , Tripsina/metabolismo
18.
J Immunol ; 134(1): 129-37, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3964811

RESUMO

The effects of ultraviolet radiation (UV) on the immune parameters of human epidermis were studied. We determined the effects of both in vitro and in vivo UV on human epidermal cell surface markers and on epidermal immune function in the allogeneic epidermal cell-lymphocyte reaction (ELR). Epidermal cells obtained immediately after in vitro and in vivo UV exposure exhibited a dose-dependent decrease in alloantigen-presenting function in the ELR. This was not the result of a decrease in the number of T6+ Dr+ Langerhans cells but was due to their being less efficient at alloantigen presentation than equivalent numbers of Langerhans cells from unirradiated skin. The reduced stimulation in the ELR immediately after UV was not reversible by the addition of exogenous IL 1 or indomethacin and thus appeared to be due to a direct effect of UV on the alloantigen-presenting function of Langerhans cells. In contrast to this suppression of the epidermal immune function when epidermal cells were obtained immediately after UV, epidermal cells harvested 24 hr or later after in vivo UV exhibited a dose-dependent enhancement of allostimulatory capacity in the ELR that peaked 3 days after UV. The time course of the enhancement of allostimulation in the ELR after in vivo UV coincided with a decrease in the percentage of Langerhans cells and the appearance within the epidermis of T6- Dr+ cells, which are derived from the bone marrow, as evidenced by their expression of the bone marrow derivation markers HLe 1 and T200. Removal of Dr+ cells but not of T6+ cells from epidermal cell suspensions harvested 3 days after in vivo UV abrogated allostimulation in the ELR, demonstrating that the T6- Dr+ cells were responsible for the observed UV-induced enhancement of alloantigen presentation. Taken together, the results indicate that the timing and dosage of UV exposure are critical factors determining whether suppression or enhancement of epidermal immune function follows UV.


Assuntos
Antígenos de Superfície/efeitos da radiação , Isoantígenos/efeitos da radiação , Células de Langerhans/efeitos da radiação , Pele/efeitos da radiação , Raios Ultravioleta , Amputação Cirúrgica , Células Cultivadas , Relação Dose-Resposta à Radiação , Humanos , Recém-Nascido , Células de Langerhans/imunologia , Células de Langerhans/ultraestrutura , Masculino , Microscopia Eletrônica , Monócitos/imunologia , Pele/imunologia , Pele/ultraestrutura
19.
J Invest Dermatol ; 82(1): 39-43, 1984 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6361169

RESUMO

We have studied various tissues from 10 patients with cicatricial pemphigoid using direct and indirect immunofluorescence, mechanical suction blister induction, and immunoelectron microscopy. In 8 of the 10 patients, direct immunofluorescence of buccal mucosa showed a linear deposition of immunoreactants, IgG and C3 being those most commonly detected. Direct immunofluorescence of skin was positive in only 4 patients. Only 1 patient had a detectable circulating anti-basement membrane zone antibody. Substitution of normal human oral mucosa for adult skin as the tissue substrate for indirect immunofluorescence did not prove useful in the detection of circulating autoantibodies. Immunoelectron microscopy was performed in the skin or mucosa (buccal or ocular) of 6 patients, revealing lamina lucida localization of in vivo-bound immunoreactants. Indirect immunofluorescence studies on mechanically induced suction blisters in skin of 2 patients with in vivo-bound IgG suggest that the lamina lucida antigen involved in cicatricial pemphigoid may be distinct from the bullous pemphigoid antigen.


Assuntos
Complemento C3/análise , Imunoglobulinas/análise , Penfigoide Mucomembranoso Benigno/imunologia , Dermatopatias Vesiculobolhosas/imunologia , Adulto , Idoso , Bochecha , Túnica Conjuntiva/imunologia , Feminino , Imunofluorescência , Histocitoquímica , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina G/análise , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Mucosa Bucal/imunologia , Pele/imunologia
20.
J Invest Dermatol ; 80(5): 392-5, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6341473

RESUMO

The basement membrane zone (BMZ) of human skin is a complex structure which contains several well-defined components including bullous pemphigoid antigen, laminin, type IV collagen, and proteoglycan. Characterization of additional basement membrane (BM) constituents has been limited by their relative inaccessibility, insolubility, and low tissue concentration. We have produced a murine monoclonal antibody that has enabled us to define a unique constituent of the BMZ of human stratified squamous epithelia. The monoclonal antibody (KF-1) was raised by standard techniques using suction blister-derived trypsinized human epidermal cells as the antigen. Indirect immunofluorescence and immunoperoxidase staining of human and rhesus monkey tissues with KF-1 produced linear BMZ staining of stratified squamous epithelia. Glandular and vascular BMs were not stained. Immunoelectron microscopic studies of normal human skin and esophagus showed specific binding of KF-1 to the lamina densa of the BMZ, a localization identical to that of type IV collagen. However, unlike type IV collagen, which is not species specific and is found in all BMs, the antigen defined by KF-1 is collagenase-resistant and is specific for primate stratified squamous epithelia. These findings confirm the existence of regional variation in BM composition, and demonstrate for the first time that the lamina densa of stratified squamous epithelial BMs contains a constituent other than type IV collagen.


Assuntos
Anticorpos Monoclonais/imunologia , Membrana Basal/imunologia , Pele/imunologia , Animais , Galinhas , Colágeno/imunologia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Cobaias , Humanos , Técnicas Imunoenzimáticas , Macaca mulatta , Camundongos/imunologia , Camundongos Endogâmicos BALB C/imunologia , Ratos
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