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1.
Int J Surg Case Rep ; 34: 56-59, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28359047

RESUMEN

BACKGROUND: The purpose of this case report is to highlight for the first time the way Medical Infrared Thermography can be a helpful tool to assist the surgeon in the surgical treatment of Hidradenitis Suppurativa inflammatory disease. METHODS: A 36-year-old man with a 7-year history of Hidradenitis Suppurativa presented inflammatory nodules in the left axilla area corresponding to Hurley stage II. Choice is made to surgically treat this patient using a wide excision protocol combined with a postoperative second intention healing. For the study purpose, an IR FLIR SC620 camera (FLIR Systems, Wilsonville, OR), having a high resolution pixel detector of 640×480 pixels for greater accuracy and higher resolution, has been used. RESULTS: For the first time in the literature, this case report on HS disease supports the idea that real-time medical infrared thermography may be helpful in establishing the true extent of disease preoperatively in the surgical room and in a similar manner, that this technique allows the surgeon to ensure all diseased lesions are removed during surgery. CONCLUSIONS: At least, medical infrared thermography seems to be a powerful tool to control the final wide surgical wound, in order to minimize recurrence risk of such a disease.

2.
J Dent Res ; 85(8): 745-50, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16861293

RESUMEN

Elastin peptides were previously reported to increase MMP expression in several cell types. We found binding of these peptides to their receptors led to enhanced MMP-3 and MMP-1 expression, but not activation, in human gingival fibroblasts cultured on plastic dishes. We hypothesized that these peptides, in a more physiological environment, might additionally trigger an MMP-3/MMP-1 activation cascade, leading to matrix lysis, as occurs in periodontitis. To test this hypothesis, we used contracted and attached lattices as gingival lamina propria equivalents. In such 3D models, supplementation of elastin peptides and plasminogen triggered an MMP-3/MMP-1 activation cascade and significant down-regulation of TIMPs production, further leading to intense collagen degradation. We propose that elastolysis, as occurs in periodontitis, potentiates collagenolysis, thus promoting disease progression.


Asunto(s)
Elastina/metabolismo , Colágenos Fibrilares/metabolismo , Encía/metabolismo , Metaloproteinasa 3 de la Matriz/metabolismo , Adulto , Western Blotting , Técnicas de Cultivo de Célula , Células Cultivadas , Activación Enzimática , Fibroblastos/metabolismo , Encía/citología , Humanos , Metaloproteinasa 1 de la Matriz/metabolismo , Persona de Mediana Edad , Modelos Biológicos , Oligopéptidos/metabolismo , Plasminógeno/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Inhibidores Tisulares de Metaloproteinasas/antagonistas & inhibidores
3.
Exp Cell Res ; 270(1): 110-8, 2001 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11597133

RESUMEN

During melanoma progression, migrating cells must cross human dermis, a type I collagen-rich tissue. We have show that MMP-1 and MMP-2 act in a cumulative manner in the in vitro invasion of a three-dimensional type I collagen matrix by melanoma cells. Two melanoma cell lines (M1Dor and M3Da) previously reported to secrete proMMP-2 in a direct relationship with their tumorigenic potential into nude mice were used (F. Capon et al., 1999, Clin. Exp. Metastasis 17, 463-469). The highly tumorigenic cell line (M3Da) displayed a five-fold faster migration rate in type I collagen matrix, compared to its lower tumorigenic counterpart (M1Dor). In parallel, activation of proMMP-2 was evidenced in M3Da- but not M1Dor-populated collagen lattices. Such enzyme activation was associated with a significant decrease in TIMP-2 and TIMP-1 production. Agents known to interfere with proMMP-2 activation, i.e., excess TIMP-2, furin convertase inhibitor, and alphavbeta3 blocking antibody, reduced by 30-40% the type I collagen invasive capacity of M3Da cells. By comparison, batimastat, a wide-spectrum MMP inhibitor, exhibited a more pronounced inhibitory effect (>70%). It suggested that other collagenases than MMP-2 could participate in type I collagen invasion. Collagenase-3 (MMP-13) was produced at low levels by melanoma cells whatever the cell culture conditions. In contrast, M3Da and M1Dor cells secreted collagenase-1 (MMP-1) following 48 h of culture on plastic dishes. Growing melanoma cells in type I collagen gel did not modify enzyme production, but induced proMMP-1 activation in M3Da but not M1Dor cell-populated lattices. Blocking the plasmin-mediated proMMP-1 activation by aprotinin inhibited type I collagen gel invasion by 30%. Since the combination of aprotinin and furin convertase inhibitor reduced collagen invasiveness by melanoma cells to a level comparable to that attained with batimastat, we conclude that both MMP-2 and MMP-1 are involved in such tissue invasion.


Asunto(s)
Movimiento Celular/fisiología , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Melanoma/fisiopatología , Animales , Colágeno , Humanos , Metaloproteinasas de la Matriz Asociadas a la Membrana , Metaloendopeptidasas/biosíntesis , Ratones , Ratones Desnudos , Invasividad Neoplásica , Inhibidor Tisular de Metaloproteinasa-2/biosíntesis , Células Tumorales Cultivadas
4.
Mol Cell Biol Res Commun ; 3(3): 173-80, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10860866

RESUMEN

To assess the contribution of the plasmin/matrix metalloproteinase cascade in lattices retraction, human gingival fibroblast-populated collagen lattices were supplemented with plasminogen. The rate of lattice retraction was enhanced by addition of plasminogen. This effect was concomitant to plasmin generation, prostromelysin-1 and procollagenase activation. Plasminogen-mediated initiation of that proteolytic cascade was accompanied by conspicuous changes in cell morphology and collagen fibers organization. At day 1 of culture fibroblasts shifted from a rounded (control) to an elongated (in presence of plgn) shape. At the latest stage of retraction, intense vacuolization around fibroblasts was noticed in plgn-supplemented lattices which paralleled the increased collagen degradation. Plgn-enhancing influence on the initial phase of lattice retraction could be totally annihilated by either aprotinin or Batimastat. Those data emphasize the crucial importance of the plasmin-MMP proteolytic cascade in granulation tissue retraction in a healing wound.


Asunto(s)
Colágeno/metabolismo , Fibrinolisina/metabolismo , Encía/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Células Cultivadas , Activación Enzimática , Fibroblastos/enzimología , Fibroblastos/metabolismo , Fibroblastos/ultraestructura , Encía/enzimología , Encía/ultraestructura , Humanos , Microscopía Electrónica de Rastreo
5.
J Dent Res ; 77(9): 1717-29, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9759669

RESUMEN

Cell shape variations and substratum re-organization during contraction of floating collagen and fibrin lattices seeded with human gingival fibroblasts were determined by computerized image analysis of light and scanning electron microscopic images. Data were compared with those obtained with lattices populated with human dermal fibroblasts. The extent of collagen lattice contraction was similar with both cell types, resulting in a two-fold decrease in the area fractions occupied by collagen fibers. Fibroblasts exhibited a rounded shape (form factors equal to 0.8 and 0.7 for gingival and dermal cells, respectively) at day 1 of culture; they possessed a more elongated appearance (with form factors equal to 0.3 and 0.15 for gingival and dermal cells, respectively) at day 7. Continuous (gingival) and discontinuous (dermal) layers of cells were evidenced at the cortex of lattices. Contractions were associated with a significant reduction of the diameters of collagen fibers. Re-organization of substratum, as analyzed by the "Rose of Directions" technique, was evidenced only at the vicinity of filopodia where fibers ran parallel to these protrusions. Several lysed matrix cavities were observed when fibrin lattices were populated with gingival but not dermal fibroblasts at day 5 of culture. Although cells in fibrin lattices exhibited morphometric parameters comparable with those in collagen lattices, no fibroblast layers could be demonstrated at gel peripheries. Fibrin matrices consisted of an isotropic network of entangled fibrin filaments from the start of culture, and only a slight reduction of the diameters of fibrin fibers could be evidenced in dermal fibroblast-populated lattices. Fibrinolysis at the vicinity of gingival fibroblasts led to an entire re-organization of substratum toward the formation of larger fibers. The differential behavior of gingival vs. dermal fibroblasts inside fibrin but not collagen matrices could therefore partly explain the increased rate of remodeling of gingiva as compared with dermis.


Asunto(s)
Colágeno/ultraestructura , Matriz Extracelular/ultraestructura , Fibrina/ultraestructura , Encía/ultraestructura , Piel/ultraestructura , Adulto , Células Cultivadas , Fibroblastos/ultraestructura , Humanos , Procesamiento de Imagen Asistido por Computador , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Valores de Referencia
6.
Int J Biochem Cell Biol ; 29(1): 181-9, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9076953

RESUMEN

We previously demonstrated that human gingival fibroblasts (HGF), but not their dermal counterparts, when seeded in retracting fibrin lattices induced intense fibrinolysis that was observed at the earliest stages of contraction and led to complete matrix degradation by day 7 of culture. Our aim was to examine the influence of mechanical forces in such fibrinolytic processes. HGF were seeded in retracting (R) e.g. free floating or non retracting (NR) e.g. anchored fibrin lattices (FL). Cultures were analysed from day 1-12 by phase contrast microscopy and scanning electron microscopy (s.e.m.). Levels of fibrin degradation products (FDP) and tissue plasminogen activator (tPA) accumulating in culture media were quantified by ELISA. Urokinase (uPA) and gelatinase A (MMP2) were identified by zymographic techniques. At the s.e.m. level, vacuolization around some HGF was noticed at the earliest stages of culture for RFL and complete degradation of lattices occurred at day 7. Formation of lysed matrix cavity was far less intense in NRFL even after 12 days of culture. FDP amounts at day 4 of culture were equal to 79 +/- 14 and 8.5 +/- 0.6 micrograms/10(5) cells for RFL and NRFL, respectively; tPA levels were equal to 5.8 +/- 0.6 (RFL) and 2.1 +/- 0.3 ng/10(5) cells (NRFL) and differences were still evident at day 7. The kinetics of tPA production were identical in either retracting fibrin or collagen lattices. On the contrary, uPA and proMMP2 productions were similar in RFL and NRFL. Isometric forces, but not the matrix support, were responsible for accelerated tPA production and fibrinolysis in HGF populated lattices.


Asunto(s)
Fibrinólisis/fisiología , Fibroblastos/metabolismo , Encía/citología , Encía/metabolismo , Fenómenos Biomecánicos , Proteínas de la Matriz Extracelular/metabolismo , Fibrina , Fibroblastos/fisiología , Humanos , Técnicas In Vitro , Cinética , Microscopía Electrónica de Rastreo , Activador de Tejido Plasminógeno/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
7.
J Cell Physiol ; 168(1): 188-98, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8647915

RESUMEN

Remodeling of the extracellular matrix by fibroblasts is an important step in the process of wound healing and tissue repair. We compared the behavior of fibroblasts from two different tissues, dermis and gingiva, in three-dimensional lattices made of two different extracellular matrix macromolecules, collagen and fibrin. Cells were grown in monolayer cultures from normal skin or gingiva and seeded in three-dimensional lattices made of either collagen of fibrin. Photonic and scanning electron microscopy did not reveal any morphological differences between the two types of fibroblasts in both sets of lattices. Both types of fibroblasts retracted collagen lattices similarly and caused only a slight degradation of the collagen substratum. By contrast, when seeded in fibrin lattices, gingival fibroblasts completely digested their substratum in less than 8 days, whereas only a slight fibrin degradation was observed with dermal fibroblasts. The ability of gingival but not dermal fibroblasts to express high levels of tissue plasminogen activators (tPA) when cultured in fibrin lattices was assessed on an immunological basis. Also, deprivation of plasminogen-contaminating fibrinogen preparations or use of tPA inhibitors markedly inhibited both fibrinolysis and retraction rates of fibrin lattices by gingival fibroblasts. Casein-zymography confirmed the intense proteolytic activity induced by fibrin in gingival fibroblasts. It was inhibited by aprotinin and phenyl methylsulfonyl fluoride (PMSF), two non-specific inhibitors of serine proteinases, and by epsilon-amino-caproic acid (epsilon ACA), an inhibitor of plasminogen activators. Monolayer cultures exhibited only trace amounts of caseinolytic activity. Our results demonstrate that the expression of proteinases by fibroblasts is dependent not only on their tissue origin but also on the surrounding extracellular matrix. The intense fibrinolytic activity of gingival fibroblasts in fibrin lattices may explain partially the high rate of healing clinically observed in gingiva.


Asunto(s)
Endopeptidasas/metabolismo , Matriz Extracelular/fisiología , Fibroblastos/enzimología , Adulto , Células Cultivadas , Fibrina/metabolismo , Encía/citología , Humanos , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Plasminógeno/metabolismo , Piel/citología , Activador de Tejido Plasminógeno/metabolismo
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