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1.
EClinicalMedicine ; 64: 102244, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37781156

RESUMO

Background: For cancer patients to effectively engage in decision making, they require comprehensive and understandable information regarding treatment options and their associated outcomes. We developed an online prediction tool and supporting communication skills training to assist healthcare providers (HCPs) in this complex task. This study aims to assess the impact of this combined intervention (prediction tool and training) on the communication practices of HCPs when discussing treatment options. Methods: We conducted a multicenter intervention trial using a pragmatic stepped wedge design (NCT04232735). Standardized Patient Assessments (simulated consultations) using cases of esophageal and gastric cancer patients, were performed before and after the combined intervention (March 2020 to July 2022). Audio recordings were analyzed using an observational coding scale, rating all utterances of treatment outcome information on the primary outcome-precision of provided outcome information-and on secondary outcomes-such as: personalization, tailoring and use of visualizations. Pre vs. post measurements were compared in order to assess the effect of the intervention. Findings: 31 HCPs of 11 different centers in the Netherlands participated. The tool and training significantly affected the precision of the overall communicated treatment outcome information (p = 0.001, median difference 6.93, IQR (-0.32 to 12.44)). In the curative setting, survival information was significantly more precise after the intervention (p = 0.029). In the palliative setting, information about side effects was more precise (p < 0.001). Interpretation: A prediction tool and communication skills training for HCPs improves the precision of treatment information on outcomes in simulated consultations. The next step is to examine the effect of such interventions on communication in clinical practice and on patient-reported outcomes. Funding: Financial support for this study was provided entirely by a grant from the Dutch Cancer Society (UVA 2014-7000).

2.
ACS Catal ; 12(22): 13838-13852, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36439035

RESUMO

A set of doped iron oxides (chromium, aluminum, gallium, indium, manganese, zinc, niobium) were prepared by a one-step coprecipitation/calcination approach evaluated for their WGS activity under industrially relevant conditions and characterized in detail. The WGS activity after ageing the doped catalyst for 4 days at 25 bar follows the order chromium ≈ aluminum > gallium > indium > manganese > zinc > niobium for copper-codoped catalysts. The activated catalysts predominantly consist of magnetite, irrespective of the dopant. Mössbauer spectra of aged catalysts showed that aluminum and zinc occupy both tetrahedral and octahedral sites of magnetite, while chromium, gallium, indium, manganese, and niobium preferentially substitute octahedral iron. The incorporation of trivalent metal ions of similar size to octahedral Fe3+ (i.e., chromium, aluminum, gallium) results in moderate to high CO conversion, irrespective of incorporation in tetrahedral or octahedral sites. The substitution of Fe2+ with Mn2+ results in an increased Fe3+/Fe2+ ratio. Incorporation of Zn2+ in tetrahedral sites (replacing Fe3+ ions) leads to a complex structure where the charge balance is compensated from the octahedral sites. Separate dopant metal oxide phases were observed in indium- and niobium-doped catalysts. XPS shows that copper is present as a separate phase in activated copper-codoped catalysts. Aluminum is identified as the most promising promoter for substituting chromium in commercial high-temperature WGS catalysts on the basis of their similar high CO conversion although incorporation of these dopants into the magnetite structure differed substantially.

3.
Qual Life Res ; 29(7): 1747-1766, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32333238

RESUMO

PURPOSE: Cancer patients are increasingly involved in decision-making processes. Hence, clinicians need to inform patients about the risks and benefits of different treatment options in order for patients to make well informed decisions. The aim of this review is to determine the effects of methods of communicating prognostic information about (1) disease progression (survival, progression, recurrence and remission), (2) side effects and complications and (3) health-related quality of life (HRQL) on cognitive, affective and behavioral outcomes in cancer patients. METHODS: A literature search was performed to select articles that were published up to  November 2019 and that examined verbal and/or visual risk communication interventions in an oncological clinical setting. RESULTS: The search yielded 14,875 studies; 28 studies were ultimately included. For disease progression information, we found that framing affects treatment choice. Furthermore, limiting the amount of progression information in a graphical display could benefit patients' understanding of risks and benefits. For prognostic information about side effects and complications, precise and defined risk information was better understood than information presented in words. When displaying HRQL data, no consensus was found on which graph type to use. CONCLUSION: Great heterogeneity in the results and methodology and in the compared communication formats precluded us from drawing any further conclusions. Practical implications for clinicians are to consider the effects that different types of framing might have on the patient and to not rely exclusively on words to describe risks, but rather include at least some form of numbers or visualization.


Assuntos
Comunicação , Tomada de Decisões/fisiologia , Neoplasias/terapia , Qualidade de Vida/psicologia , Medição de Risco/métodos , Progressão da Doença , Humanos
4.
J Invest Dermatol ; 117(6): 1369-81, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11886497

RESUMO

During cutaneous wound repair the epidermis avoids the fibrin-rich clot; rather it migrates down the collagen-rich dermal wound margin and over fibronectin-rich granulation tissue. The mechanism(s) underlying keratinocyte movement in this precise pathway has not been previously addressed. Here we demonstrate that cultured human keratinocytes do not express functional fibrinogen/fibrin receptors, specifically alpha v beta 3. Biologic modifiers known to induce integrin expression or activation did not induce adhesion to fibrin, fibrinogen, or its fragments. Epidermal explant outgrowth and single epidermal cell migration failed to occur on either fibrin or fibrinogen. Surprisingly, fibrin and fibrinogen mixed at physiologic molar ratios with fibronectin abrogated keratinocyte attachment to fibronectin. Keratinocytes transduced with the beta 3 integrin subunit cDNA, expressed alpha v beta 3 on their surface and attached to and spread on fibrinogen and fibrin. beta-gal cDNA-transduced keratinocytes did not demonstrate this activity. Furthermore, beta 3 cDNA-transduced keratinocyte adhesion to fibrin was inhibited by LM609 monoclonal antibody to alpha v beta 3 in a concentration-dependent fashion. From these data, we conclude that normal human keratinocytes cannot interact with fibrinogen and its derivatives due to the lack of alpha v beta 3. Thus, fibrinogen and fibrin are authentic anti-adhesive for keratinocytes. This may be a fundamental reason why the migrating epidermis dissects the fibrin eschar from wounds.


Assuntos
Fibrina/farmacologia , Fibrinogênio/farmacologia , Queratinócitos/citologia , Queratinócitos/fisiologia , Cicatrização/fisiologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Bucladesina/farmacologia , Carcinógenos/farmacologia , Cátions Bivalentes/farmacologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/fisiologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Centrifugação , DNA Complementar , Células Epidérmicas , Fator de Crescimento Epidérmico/farmacologia , Epiderme/lesões , Proteínas da Matriz Extracelular/metabolismo , Fibrina/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/farmacologia , Fibrinogênio/metabolismo , Expressão Gênica/fisiologia , Humanos , Integrina beta3 , Glicoproteínas da Membrana de Plaquetas/genética , Glicoproteínas da Membrana de Plaquetas/metabolismo , Receptores de Vitronectina/genética , Receptores de Vitronectina/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Transfecção , Fator de Crescimento Transformador beta/farmacologia , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária , Cicatrização/efeitos dos fármacos
7.
J Invest Dermatol ; 114(4): 647-53, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10733668

RESUMO

We examined the role of the serine proteinase plasmin in regulating fibroblast-mediated tissue remodeling during wound healing. As an in vitro model system, collagen lattices were seeded with human dermal fibroblasts, and various concentrations of plasmin were added to the medium of the contracting lattices. Within 16 h, fibroblast-populated collagen lattices treated with plasmin rapidly contracted from approximately 20 mm to less than 2 mm in diameter. Measurements of collagen lattices with radiolabeled collagen indicated that, when these lattices included either fibroblasts or conditioned medium derived from fibroblast-populated collagen lattices, exogenous plasmin induced collagen degradation and rapid lattice contraction. Western blot analyses of conditioned medium demonstrated that fibroblasts in collagen lattices secreted the latent matrix metalloproteinase, MMP-1, which was subsequently cleaved by plasmin. Additionally, rapidlattice contraction and collagen degradation were blocked when collagen lattices were treated simultaneously with plasmin and aprotinin or a tissue inhibitor of metalloproteinases, TIMP-1. These results provide strong evidence that plasmin regulates rapid contraction of collagen lattices by activating fibroblast-secreted MMP-1 that triggers collagen degradation. The findings from this study suggest that fibroblast-populated collagen lattices can be used as an in vitro model system to investigate the mechanisms by which plasmin and cell-secreted plasminogen activators control MMP-1 mediated extracellular lattice degradation and remodeling during wound healing.


Assuntos
Colágeno/metabolismo , Fibrinolisina/fisiologia , Fibroblastos/fisiologia , Aprotinina/farmacologia , Linhagem Celular , Fibroblastos/metabolismo , Humanos , Recém-Nascido , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Modelos Biológicos , Inibidores de Proteases/farmacologia , Inibidores de Serina Proteinase/farmacologia , Inibidor Tecidual de Metaloproteinase-1/farmacologia , Cicatrização
8.
Clin Cancer Res ; 5(5): 1041-56, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10353737

RESUMO

The generation of vascular stroma is essential for solid tumor growth and involves stimulatory and inhibiting factors as well as stromal components that regulate functions such as cellular adhesion, migration, and gene expression. In an effort to obtain a more integrated understanding of vascular stroma formation in breast carcinoma, we examined expression of the angiogenic factor vascular permeability factor (VPF)/vascular endothelial growth factor (VEGF); the VPF/VEGF receptors flt-1 and KDR; thrombospondin-1, which has been reported to inhibit angiogenesis; and the stromal components collagen type I, total fibronectin, ED-A+ fibronectin, versican, and decorin by mRNA in situ hybridization on frozen sections of 113 blocks of breast tissue from 68 patients including 28 sections of breast tissue without malignancy, 18 with in situ carcinomas, 56 with invasive carcinomas, and 8 with metastatic carcinomas. A characteristic expression profile emerged that was remarkably similar in invasive carcinoma, carcinoma in situ, and metastatic carcinoma, with the following characteristics: strong tumor cell expression of VPF/VEGF; strong endothelial cell expression of VPF/VEGF receptors; strong expression of thrombospondin-1 by stromal cells and occasionally by tumor cells; and strong stromal cell expression of collagen type I, total fibronectin, ED-A+ fibronectin, versican, and decorin. The formation of vascular stroma preceded invasion, raising the possibility that tumor cells invade not into normal breast stroma but rather into a richly vascular stroma that they have induced. Similarly, tumor cells at sites of metastasis appear to induce the vascular stroma in which they grow. We conclude that a distinct pattern of mRNA expression characterizes the generation of vascular stroma in breast cancer and that the formation of vascular stroma may play a role not only in growth of the primary tumor but also in invasion and metastasis.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Carcinoma in Situ/irrigação sanguínea , Carcinoma/irrigação sanguínea , Neovascularização Patológica , Adenocarcinoma Mucinoso/irrigação sanguínea , Adenocarcinoma Mucinoso/química , Adenocarcinoma Mucinoso/patologia , Biomarcadores , Biópsia , Mama/irrigação sanguínea , Mama/química , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Carcinoma/química , Carcinoma/patologia , Carcinoma in Situ/química , Carcinoma Ductal de Mama/irrigação sanguínea , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/irrigação sanguínea , Carcinoma Intraductal não Infiltrante/química , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Lobular/irrigação sanguínea , Carcinoma Lobular/química , Carcinoma Lobular/patologia , Proteoglicanas de Sulfatos de Condroitina/análise , Colágeno/análise , Decorina , Fatores de Crescimento Endotelial/análise , Endotélio Vascular/química , Células Epiteliais/química , Proteínas da Matriz Extracelular , Feminino , Doença da Mama Fibrocística/metabolismo , Doença da Mama Fibrocística/patologia , Fibronectinas/análise , Secções Congeladas , Humanos , Hibridização In Situ , Lectinas Tipo C , Metástase Linfática , Linfocinas/análise , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Neoplasias/análise , Isoformas de Proteínas/análise , Proteoglicanas/análise , Proteínas Proto-Oncogênicas/análise , RNA Mensageiro/análise , RNA Neoplásico/análise , Receptores Proteína Tirosina Quinases/análise , Receptores de Fatores de Crescimento/análise , Receptores de Fatores de Crescimento do Endotélio Vascular , Células Estromais/patologia
9.
J Biol Chem ; 274(25): 17876-84, 1999 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-10364233

RESUMO

Alternative splicing of the fibronectin gene transcript gives rise to a group of adhesive glycoproteins showing restricted spatial and temporal expression during embryonic development, tumor growth, and tissue repair. Alternative splicing occurs in three segments termed EIIIB, EIIIA, and V. The EIIIA (or ED-A) segment of fibronectin is expressed prominently but transiently in healing wounds coincident with fibroblast expression of an activation marker, smooth muscle cell alpha-actin. A monoclonal antibody (IST-9) to the EIIIA segment blocks transforming growth factor-beta-mediated smooth muscle cell alpha-actin expression by fibroblasts in culture. A second monoclonal antibody (DH1) blocks chondrocyte condensation in chicken embryos. We find that IST-9 and DH1 react with human, rat, and chicken but not with mouse or frog EIIIA, suggesting that His44 may be important for antibody binding. A series of deletion mutants of rat EIIIA, constructed as glutathione S-transferase fusion proteins, do not react with either IST-9, DH1, or a third monoclonal antibody (3E2). Mutations of pairs of amino acids to alanine have little effect, except for either (Val34Thr35) or (Tyr36Ser37), which are located in a beta strand upstream from His44. For these double mutants, the binding to all three monoclonal antibodies is markedly reduced. By contrast, single mutants at Thr35, Tyr36, or Ser37 retain full activity, suggesting that the epitope for these antibodies is determined in part by conformation. Alanine-scanning mutagenesis of rat EIIIA demonstrates the importance of Ile43 and His44 for binding. Mutation of frog EIIIA (normally Val43Lys44) to rat (Ile43His44) is sufficient to restore fully IST-9 binding and much of the activity of DH1 and 3E2. Our findings demonstrate that the function-blocking antibodies, IST-9 and DH1, bind to the Ile43 and His44 residues in a conformationally dependent fashion, implicating the loop region encompassing both residues as critical for mediating EIIIA function.


Assuntos
Anticorpos Monoclonais/imunologia , Fibronectinas/química , Fibronectinas/imunologia , Processamento Alternativo , Sequência de Aminoácidos , Animais , Reações Antígeno-Anticorpo/genética , Mapeamento de Epitopos , Fibronectinas/genética , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Ligação Proteica , Conformação Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes/imunologia , Deleção de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
10.
Transplantation ; 65(5): 699-706, 1998 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9521206

RESUMO

BACKGROUND: Allograft rejection is associated with infiltration of inflammatory cells and local deposition of fibronectin (FN). This study was carried out to examine the hypothesis that peptides known to specifically block adhesive interactions between the connecting segment-1 (CS1)-binding domain of FN and alpha4beta1 integrin on circulating cells may interfere with the immune cascade, which would lead to acute rejection in transplant recipients. METHODS AND RESULTS: Cardiac allografts from Lewis x Brown Norway F1 hybrids were rejected in 7+/-1 days in Lewis rats. Treatment with bioactive CS1 peptides (4 mg/kg/day i.v. for 7 days) abrogated acute rejection and prolonged cardiac allograft survival to 13+/-1 days (P<0.001). This effect correlated with decreased expression of total fibronectin and cell adhesion molecules, such as alpha4beta1, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, as well as reduced infiltration by CD4+ and CD8+ T cells at the graft site. Treatment with CS1 peptides decreased alloantigen activation, as evidenced by decreased intragraft infiltration by CD25+ cells, and diminished expression of mRNA coding for Th1 (interleukin [IL]-2, interferon-gamma)- and Th2 (IL-4, IL-5, IL-6)-type cytokines. CS1-mediated immunosuppressive effects could be reversed and acute rejection recreated after adjunctive treatment of rats with recombinant IL-2. CONCLUSION: Our data are consistent with the model in which in vivo interaction between the alpha4beta1 integrin receptor and the cell-associated CS1 motif of FN is critical for rejection cascade. The novel therapeutic approach of selectively blocking the alpha4beta1-FN activation pathway with CS1 peptides prevents acute allograft rejection by inhibiting expansion of antigen-specific T cells and inducing a transient state of cytokine-responsive anergy in the residual T-cell population.


Assuntos
Fibronectinas/metabolismo , Rejeição de Enxerto , Transplante de Coração/imunologia , Integrinas/metabolismo , Receptores de Retorno de Linfócitos/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Ligação Competitiva , Complexo CD3/genética , Moléculas de Adesão Celular/metabolismo , Citocinas/genética , Citocinas/metabolismo , Fibronectinas/química , Imunidade Celular , Integrina alfa4beta1 , Masculino , Dados de Sequência Molecular , Peptídeos/administração & dosagem , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Ratos Sprague-Dawley
12.
Clin Lab Med ; 17(2): 299-314, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9243075

RESUMO

The foregoing discussion has presented a summary of many of the optical microscopic methods in use by researchers and clinicians. Along with emerging technologies, such as laser tweezers and scissors, which are outside the scope of this review, the methodologies discussed here ensure that the optical microscope will remain a central tool for biomedical research.


Assuntos
Diagnóstico por Imagem , Microscopia , Humanos , Hibridização in Situ Fluorescente , Processamento de Sinais Assistido por Computador
13.
Am J Pathol ; 150(5): 1701-9, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9137094

RESUMO

P- and E-selectins are adhesion molecules expressed on activated endothelium and platelets at sites of vascular injury and inflammation. The selectins are important for leukocyte recruitment. Because little is known about the role of selectins in wound healing, we studied cutaneous wound repair of full-thickness excisional skin wounds in mice lacking P-selectin, E-selectin, or both of these selectins. The absence of either selectin alone had no notable effect on healing, and the only deficit observed was a delay in early neutrophil extravasation in the P-selectin-deficient mice. Mice deficient in both P- and E-selectins had markedly reduced recruitment of inflammatory cells and impaired closure of the wounds. Wound sections, studied up to 3 days after wounding, showed significant impairment of neutrophil influx. Macrophage numbers were also reduced in the double mutants at 3 and 7 days after wounding as compared with wild-type mice. Additionally, a wider epithelial gap in the wounds of the P- and E-selectin-double-deficient mice 3 days after wounding indicated delayed keratinocyte migration. These results demonstrate an important combined role for P- and E-selectins in processes leading to wound healing.


Assuntos
Endotélio Vascular/fisiologia , Selectinas/fisiologia , Cicatrização/fisiologia , Animais , Movimento Celular/genética , Feminino , Tecido de Granulação/patologia , Queratinócitos/fisiologia , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/fisiologia , Selectinas/genética , Pele/patologia , Cicatrização/genética
14.
Am J Pathol ; 150(5): 1757-72, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9137099

RESUMO

Allograft rejection is associated with infiltration of inflammatory cells and deposition of extracellular matrix proteins. The extent to which diversity in the extracellular matrix regulates inflammatory cell function in transplants remains unclear. One group of extracellular matrix proteins, termed fibronectins (FNs), exhibits inherent diversity as a consequence of alternative splicing in three segments: EIIIA, EIIIB, or V. Although the EIIIA segment has documented functions in mesenchymal cell differentiation, neither this segment nor the EIIIB segment have been tested for effects specific to leukocyte functions. By contrast, the V region can include the CS-1 segment to which leukocytes may adhere through alpha 4 beta 1 integrins. In this study, we demonstrate that EIIIA+, EIIIB+, and V+ FN variants are synthesized, primarily by macrophages in distinct temporal and spatial patterns in two rat cardiac transplant models: either with antigenic challenge, allografts, or without challenge, isografts. The ratio of EIIIA inclusion into FN increases by day 1 in allografts and isografts and remains high until allografts are rejected (approximately 7 days) but falls to normal levels in tolerated isografts (day 6). EIIIB+ FN ratios in allografts peak later than do EIIIA+ FNs (day 4). EIIIB+ FN ratios remain relatively low in isografts. Interestingly, EIIIA+ and EIIIB+ FNs are deposited prominently in the myocardium of rejecting allografts in close association with infiltrating leukocytes, and FN expression and deposition are prominent at sites of infarction. By contrast, these FNs are largely restricted to the epicardium and to a lesser degree in the immediately adjacent myocardium in isografts. CS-1+ FNs increase in allografts and isografts at 3 hours after transplantation but are particularly prominent in allografts 1 to 3 days before rejection. Our data suggest that FN splicing variants have a differential role in the effector functions of leukocytes in allografts and isografts and provide a foundation for testing their function on leukocytes and a rationale for FN-based therapeutics to modulate allograft rejection in transplant recipients.


Assuntos
Processamento Alternativo , Fibronectinas/genética , Transplante de Coração/patologia , Animais , Northern Blotting , Movimento Celular , Fibronectinas/química , Fibronectinas/metabolismo , Técnica Direta de Fluorescência para Anticorpo , Transplante de Coração/imunologia , Hibridização In Situ , Masculino , Miocárdio/química , Miocárdio/metabolismo , Miocárdio/patologia , Sondas RNA , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Ribonucleases , Coloração e Rotulagem , Transplante Homólogo , Transplante Isogênico
16.
J Urol ; 157(1): 306-10, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8976286

RESUMO

PURPOSE: The extracellular matrix that is present at sites of tissue repair in most instances undergoes an orderly transition from a fibrin containing matrix to collagen-rich scar. However, in some conditions, such as Peyronie's disease, fibrin persists. Evidence from a number of experimental systems indicates that extracellular matrix proteins and their receptors serve an important function in regulating cell behaviors. Thus, the presence of the fibrin matrix is likely to have important implications in the course of either normal or pathogenic wound healing as occurs in Peyronie's disease. Potential mechanisms by which the fibrin rich provisional matrix appears in healing wounds are presented. MATERIALS AND METHODS: Methodologies, such as in situ hybridization, immunolocalization and labeled tracer techniques, were used in our study. RESULTS: We found by these approaches that the 2 general mechanisms that contribute to the generation of the wound extracellular matrix are leakage of plasma proteins, such as plasma fibronectin and fibrinogen, and the synthesis of variants of fibronectin by wound cells. CONCLUSIONS: Developing an understanding of the mechanisms that regulate the appearance of these matrix proteins may provide new avenues for therapy in conditions such as Peyronie's disease in which the temporal pattern of the provisional matrix deposition is abnormal.


Assuntos
Fibrina/fisiologia , Fibronectinas/fisiologia , Induração Peniana/etiologia , Cicatrização/fisiologia , Animais , Fatores de Crescimento Endotelial/fisiologia , Matriz Extracelular , Linfocinas/fisiologia , Masculino , Roedores , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
17.
J Invest Dermatol ; 105(1): 44-50, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7615975

RESUMO

Expression of vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) is markedly increased in the epidermis of lesional psoriatic skin and in healing skin wounds. In this study, we characterized the effects of several cytokines and growth factors on the expression and secretion of VPF/VEGF mRNA and protein by cultured human epidermal keratinocytes, as well as the effect of VPF/VEGF on the growth of cultured human dermal microvascular endothelial cells. Transforming growth factor-alpha, epidermal growth factor, and phorbol myristate acetate markedly stimulated VPF/VEGF mRNA expression by cultured keratinocytes; as in psoriatic skin, the three most common VPF/VEGF isoforms (encoding proteins of 121, 165, and 189 amino acids) were upregulated to an equal extent. Transforming growth factor (TGF)-alpha, epidermal growth factor, and phorbol myristate acetate also enhanced the secretion of VPF/VEGF by keratinocytes; in contrast, a number of other cytokines including interleukin (IL)-1, IL-6, IL-8, tumor necrosis factor-alpha, interferon-gamma, and transforming growth factor-beta did not induce VPF/VEGF secretion. The VPF/VEGF secreted by keratinocytes was biologically active in that, like recombinant human VPF/VEGF, it potently stimulated dermal endothelial cell proliferation. Scatchard analysis revealed two high-affinity VPF/VEGF binding sites on dermal endothelial cells with dissociation constants of 51 pM and 2.9 pM. These results suggest that the avascular epidermis has the capacity to regulate dermal angiogenesis and microvascular permeability by a paracrine mechanism involving the secretion of VPF/VEGF. Similar mechanisms may be anticipated in a variety of inflammatory and neoplastic skin diseases characterized by microvascular hyperpermeability, edema, and angiogenesis.


Assuntos
Fatores de Crescimento Endotelial/biossíntese , Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/efeitos dos fármacos , Linfocinas/biossíntese , Linfocinas/farmacologia , Mitógenos/farmacologia , Sítios de Ligação , Células Cultivadas , Meios de Cultivo Condicionados , Fator de Crescimento Epidérmico/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Queratinócitos/metabolismo , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador alfa/farmacologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
18.
Int Arch Allergy Immunol ; 107(1-3): 233-5, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7542074

RESUMO

Vascular permeability factor (VPF), also known as vascular endothelial growth factor (VEGF), is a multifunctional cytokine that is overexpressed in many transplantable animal and autochtonous human cancers, in healing wounds, and in chronic inflammatory disorders such as psoriasis and rheumatoid arthritis. All of these entities are characterized by angiogenesis, altered extracellular matrix, and variable degrees of hypoxia. In addition, two VPF/VEGF receptors, flt-1 and kdr, are overexpressed by endothelial cells that line the microvessels that supply these tumors/inflammatory reactions. On the basis of these and other data, we have proposed a model of angiogenesis in which VPF/VEGF plays a central role: this model is applicable to tumors and also to the angiogenesis that occurs in non-neoplastic processes.


Assuntos
Fatores de Crescimento Endotelial/farmacologia , Inflamação/fisiopatologia , Linfocinas/farmacologia , Modelos Biológicos , Neoplasias/fisiopatologia , Neovascularização Patológica/fisiopatologia , Animais , Matriz Extracelular/metabolismo , Humanos , Proteínas de Neoplasias/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Receptores de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Cicatrização/fisiologia
20.
J Immunol ; 154(6): 2801-7, 1995 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-7876550

RESUMO

Delayed hypersensitivity (DH) is a T cell-mediated form of immune response characterized by a predominantly perivascular, mononuclear cell infiltrate. The venules in DH reactions are hyperpermeable to plasma proteins, leading to extravasation of plasma fibrinogen and its extravascular clotting to form a fibrin gel that promotes induration and angiogenesis. The mechanisms responsible for microvascular hyperpermeability in DH are unknown. Recently, a cytokine named vascular permeability factor (VPF, also known as vascular endothelial growth factor or VEGF) has been implicated in the chronic vascular hyperpermeability and angiogenesis of solid and ascites tumors, healing wounds, rheumatoid arthritis, and psoriasis. These findings suggested that VPF/VEGF might also have a role in the pathogenesis of DH. Two model systems were studied: allergic contact dermatitis to poison ivy in human volunteers and classical tuberculin hypersensitivity in rats. In both, in situ hybridization revealed that the mRNAs encoding VPF/VEGF were strikingly overexpressed in keratinocytes of the epidermis; scattered mononuclear cells infiltrating the dermis also overexpressed VPF/VEGF mRNA, to a greater extent in rat tuberculin than in human contact reactions. In contact reactions, mRNAs for two VPF/VEGF vascular endothelial cell receptors, flt-1 and KDR, were also strikingly overexpressed. Abundant fibrin deposition in both models confirmed that dermal microvessels were indeed hyperpermeable to plasma fibrinogen. These results implicate VPF/VEGF as a potentially important mediator in the pathogenesis of cell-mediated immunity and provide further evidence that products of epithelial cells may regulate the inflammatory response.


Assuntos
Dermatite Alérgica de Contato/imunologia , Fatores de Crescimento Endotelial/biossíntese , Linfocinas/biossíntese , Receptores Proteína Tirosina Quinases/biossíntese , Receptores de Fatores de Crescimento/biossíntese , Animais , Catecóis/imunologia , Dermatite Alérgica de Contato/patologia , Feminino , Humanos , Hipersensibilidade Tardia/imunologia , Hipersensibilidade Tardia/patologia , Imuno-Histoquímica , Hibridização In Situ , RNA Mensageiro/biossíntese , Ratos , Receptores de Fatores de Crescimento do Endotélio Vascular , Tuberculina/imunologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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