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ABSTRACT: A beneficial effect of gentamicin supplemented mesh material on tissue integration is known. To further elucidate the interaction of collagen and MMP-2 in chronic foreign body reaction and to determine the significance of the MMP-2-specific regulatory element (RE-1) that is known to mediate 80% of the MMP-2 promoter activity, the spatial and temporal transcriptional regulation of the MMP-2 gene was analyzed at the cellular level.
A PVDF mesh material was surface modified by plasma-induced graft polymerization of acrylic acid (PVDF+PAAc). Three different gentamicin concentrations were bound to the provided active sites of the grafted mesh surfaces (2, 5 and 8 μg/mg). 75 male transgenic MMP-2/LacZ mice harbouring the LacZ reporter gene under control of MMP-2 regulatory sequence -1241/+423, excluding the RE-1 were randomized to five groups. Bilateral of the abdominal midline one of the five different meshes was implanted subcutaneously in each animal. MMP-2 gene transcription (anti-ß-galactosidase staining) and MMP-2 protein expression (anti-MMP-2 staining) were analyzed semiquantitatively by immunohistochemistry 7, 21 and 90 days after mesh implantation. The collagen type I/III ratio was analyzed by cross polarization microscopy to determine the quality of mesh integration.
The perifilamentary ß-galactosidase expression as well as the collagen type I/III ratio increased up to the 90th day for all mesh modifications, whereas no significant changes could be observed for MMP-2 protein expression between days 21 and 90. Both the 5 and 8 μg/mg gentamicin group showed significantly reduced levels of ß-galactosidase expression and MMP-2 positive stained cells when compared to the PVDF group on day 7, 21 and 90 respectively (5 μg/mg: p < 0.05 each; 8 μg/mg: p < 0.05 each). Though the type I/III collagen ratio increased over time for all mesh modifications significant differences to the PVDF mesh were only detected for the 8 μg/mg group at all 3 time points (p < 0.05 each).
Our current data indicate that lack of RE-1 is correlated with increased mesh induced MMP-2-gene expression for coated as well as for non-coated mesh materials. Gentamicin coating reduced MMP-2 transcription and protein expression. For the 8 μg/mg group this effect is associated with an increased type I/III collagen ratio. These findings suggest that gentamicin is beneficial for tissue integration after mesh implantation, which possibly is mediated via RE-1.
BMC Surgery 01/2012; 12:1. · 1.33 Impact Factor
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ABSTRACT: Mesh biocompatibility is basically determined by the foreign body reaction (FBR). In contrast to physiological wound healing and scar formation, the FBR at the host-tissue/biomaterial interface is present for the lifetime of the medical device. The cellular interactions at the mesh/tissue interface proceed over time ending up in a chronic inflammatory process. The time course of the FBR has been studied extensively and consists of three crucial steps that are protein absorption, cell recruitment and, finally, fibrotic encapsulation and extracellular matrix formation. Each of these steps involves a complex cascade of immune modulators including soluble mediators and various cell types. Recent research has focused on the cellular and molecular interactions of the distinct phases of the FBR offering a new basis for therapeutical strategies. The highly dynamic process of the FBR is considerably influenced by the biomaterial composition. Modifications of the type of polymer, the material weight, the filament structure and the pore size are realized and have substantial effects on the in vivo biocompatibility. Moreover, modern mesh technology aims to utilize the available implants as carrier systems for bioactive drugs. Studies in animal models account for the efficiency of these drugs that aim to reduce mesh-related infections or to minimize FBR by influencing inflammation or extracellular matrix remodelling. A thorough understanding of the molecular mechanisms of FBR provides a sophisticated background for the development of new biomaterials at least as carrier systems for bioactive reagents to reduce inflammation and to improve clinical outcome.
Langenbeck s Archives of Surgery 04/2011; 397(2):255-70. · 1.81 Impact Factor
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ABSTRACT: The inflammatory response to peritoneal injury is considered to be of particular importance in adhesion formation. The aim of this study was to investigate the dynamics of inflammatory mediators in peritoneal adhesions.
In 60 male rats, a peritoneal defect was performed using a standardized cecal abrasion model. On days 3, 5, 14, 30, 60, and 90, ten animals were sacrificed. The expression of five integral mediators for the cellular immune response (macrophages, T lymphocytes), inflammation (COX-2), cell differentiation, and proliferation (ß-catenin, c-myc) in visceral and parietal adhesions were analyzed.
A distinct infiltration of macrophages was observed in all animals up to the 90th postoperative day with a peak on day 3 for visceral adhesions (26.3 ± 5.6%) and on day 14 for parietal adhesions (5.1 ± 1.1%). Compared to parietal adhesions, macrophage levels were significantly higher on day 3 (p = 0.001) and 5 (p = 0.002) but significantly lower on days 30, 60, and 90 in visceral adhesions (p = 0.041; p = 0.001; p = 0.017). T lymphocytes were detected over time with the highest levels on day 3 (visceral 4.0 ± 0.7%; parietal 6.7 ± 2.9%). High levels of COX-2 expression could be detected for the whole observation period. Positive expression of both ß-catenin and c-myc was detected in persistent adhesions; however, no expression of c-myc was observed in parietal adhesions.
The inflammatory reaction in adhesions is not limited to the early postoperative phase. Macrophages may be fundamental in triggering adhesions, and the presence of T cells indicates an additional role of the adoptive immune system. Identification of chemokines and chemokine receptors that trigger the cellular immune response might be a potential option to minimize adhesion formation.
Langenbeck s Archives of Surgery 02/2011; 396(3):371-8. · 1.81 Impact Factor
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ABSTRACT: Surgical meshes today represent a group of implants mainly used for hernia repair. Modern hernia surgery is no longer imaginable without the application of these special biomaterials leading to millions of implantations each year worldwide. Because clinical trials are insufficient to evaluate the distinct effects of modified mesh materials in regard to tissue biocompatibility and functionality, a basic understanding of the physicochemical properties of mesh materials, as well as the underlying cause for hernia formation, is essential for a rational selection of the most appropriate device. The most important properties of meshes were found to be the type of filament, tensile strength, and experimental data, which indicate that particularly the mesh's porosity is of outstanding importance.
Seminars in Immunopathology 01/2011; 33(3):235-43. · 6.27 Impact Factor
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ABSTRACT: Reinforcement of the abdominal wall by alloplastic mesh material results in a chronic foreign body reaction which is characterized by a transcriptionally induced overexpression of the matrix metalloproteinases-2 (MMP-2). Mesh modification represents a new approach to normalize the MMP-2 expression and thereby to reduce the foreign body reaction. Because of its proven beneficial effect on tissue integration, the influence of gentamicin-supplemented polyvinylidenfluoride (PVDF) mesh materials on MMP-2 transcription and protein expression was investigated in transgenic reporter mice harboring MMP-2 regulatory sequence-1686/+423.
A PVDF mesh material was surface-modified by plasma-induced graft polymerization of acrylic acid (PVDF + PAAc). Three different gentamicin concentrations were bound to the provided active sites of the grafted mesh surfaces (2, 5, and 8 microg/mg). Seventy-five male transgenic MMP-2/LacZ CD1-tg mice harboring MMP-2 regulatory sequences -1686/+423 were randomized to five groups. Bilateral of the abdominal midline, one of the five different meshes was implanted subcutaneously in each animal. MMP-2 gene transcription and protein expression were analyzed semiquantitatively 7, 21, and 90 days after mesh implantation. The collagen type I/III ratio was analyzed by cross-polarization microscopy to determine the quality of mesh integration.
The perifilamentary MMP-2 protein expression as well as the MMP-2 promoter activity decreased over time, whereas the collagen type I/III ratio increased up to the 90th day for all mesh modifications. The 8-microg/mg mesh material showed significantly reduced levels of MMP-2-positive stained cells when compared with the PVDF group on days 7, 21, and 90 (p = 0.008; p = 0.016; p = 0.016). In accordance, the 8-microg/mg group revealed a significant reduction of beta-galactosidase-positive stained cells at each time point in comparison with the PVDF group (p = 0.008; p = 0.047; p = 0.016). Though the type I/III collagen ratio increased over time for all mesh modifications significant differences to the PVDF mesh could only detected for 8-microg/mg group (p = 0.008; p = 0.032; p = 0.016).
Our results show a dose-dependent effect of gentamicin. The reduced MMP-2 protein expression and transcription after mesh coating with 8 microg/mg gentamicin together with the improved collagen type I/III hint on an advanced tissue integration even in the long-term. Subsequent studies are needed to elucidate interaction of collagen and MMP-2 in chronic foreign body reaction.
Langenbeck s Archives of Surgery 02/2010; 395(4):413-20. · 1.81 Impact Factor
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ABSTRACT: Family history, male gender and age are significant risk factors for inguinal hernia disease. Family history provides evidence for a genetic trait and could explain early recurrence after inguinal hernia repair despite technical advance at least in a subgroup of patients. This study evaluates if age and family history can be identified as risk factors for early recurrence after primary hernia repair.
We performed an observational cohort study for 75 patients having at least two recurrent hernias. The impact of age, gender and family history on the onset of primary hernias, age at first recurrence and recurrence rates was investigated.
44% (33/75) of recurrent hernia patients had a family history and primary as well as recurrent hernias occurred significantly earlier in this group (p = 0.04). The older the patients were at onset the earlier they got a recurrent hernia. Smoking could be identified as on additional risk factor for early onset of hernia disease but not for hernia recurrence.
Our data reveal an increased incidence of family history for recurrent hernia patients when compared with primary hernia patients. Patients with a family history have their primary hernias as well as their recurrence at younger age then patients without a family history. Though recurrent hernia has to be regarded as a disease caused by multiple factors, a family history may be considered as a criterion to identify the risk for recurrence before the primary operation.
BMC Surgery 01/2009; 9:18. · 1.33 Impact Factor
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ABSTRACT: Recurrence is the main reason for early death of cancer patients. Therefore, survival curves are regarded as crucial tools for clinicians to evaluate therapies and to estimate the patients' prognosis. Current models for the development of recurrence are based on the assumption of a residual cancer cell burden after therapy. Accordingly, in assumption of an exponential cell growth of the cancer cells an S-shaped decline of the survival curve is expected with earlier onset in case of advanced cancer and a later manifestation in case of little residual tumour. However, many survival curves do not reflect any S-shaped configuration and thus may question the current concept.
To test, whether the incidence for developing a recurrence may be considered as remaining constant over time, we analysed survival data of 446 patients with gastric cancer, operated from 1975-2001 in the Surgical Department of the RWTH Aachen.
All survival curves, even after sub-grouping according to UICC stage, show a monotonous decline without any apparent S-shape. The impact of TNM and UICC stage to predict the survival in patients is estimated by Cox regression, for estimation the risk for death a logistic regression is performed. Whereas the presence of metastasis lowers the prognosis significantly with a hazard ratio of 1.57 and an odds ratio of 7.56, respectively, a significant relevance for the UICC stage, the tumour size or the lymph node status cannot be proven. Furthermore, the two assumptions: (1) that 20% of patients who are still alive after 5 years have been cured, and (2) that the remainder develop a recurrence in constantly 7.3% per month, are able to configure the survival curve almost precisely (correlation coefficient between calculated and observed survival rate r > 0.99).
The absence of any S-shaped survival curve configuration is not in accordance with the focus on residual tumour clones with its exponential growth as the decisive process for recurrence development. In contrast, the monotonous decline of surviving patients is best reflected by a constant incidence of recurrence. The (time) constancy of the recurrence incidence encourages the view of recurrent cancer as a chronic problem of a carcinogenic environment. Furthermore, it supports new anticancer therapies which rather targets cell regulation and immunology instead of acting cytotoxic.
Langenbeck s Archives of Surgery 03/2008; 393(2):149-55. · 1.81 Impact Factor
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ABSTRACT: Peritoneal adhesions are common and lead to significant clinical morbidity and mortality. Besides various individual factors, notably the inflammatory response to peritoneal defects affects adhesion formation. The aim of this study was to investigate whether there is inflammatory activity even in persistent adhesions.
Tissue specimens of 40 patients suffering peritoneal adhesions were prospectively collected. Expression profiles of seven parameters as potential mediators in cellular immune response, cell differentiation, and wound healing were analyzed (macrophages [CD68], B-lymphocytes [CD20] and T-lymphocytes [CD45], cyclo-oxygenase-2 [COX-2], Notch-3, beta-catenin, and c-myc). Furthermore, clinical details and co-morbidities were recorded.
Infiltrates of mononuclear round cells were found in all adhesion specimens irrespective of the maturity. Immunohistochemical analysis identified mononuclear round cells as macrophages (CD68) and as T-lymphocytes (CD45). Expression of CD68 was significantly elevated in adhesion tissue with an age<12 months. Positive expression of CD45, COX-2, Notch-3, beta-catenin, and c-myc, was observed even in long-lasting adhesions.
A persistent inflammatory process has to be considered, even in mature adhesions. Macrophages may play an important role in triggering adhesions, whereas T-cells and the Notch-3/beta-catenin complex signaling pathway may play a crucial role in maintaining adhesions. These findings indicate that adhesions should not be regarded simply as an adynamic result of an operative trauma but rather may be grasped as a permanent process in remodeled tissue.
World Journal of Surgery 03/2008; 32(2):296-304. · 2.36 Impact Factor
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ABSTRACT: Peritoneal adhesions are caused by intra-abdominal surgery and can lead to relevant complications. Adhesions are supposed to consist of avascular scar tissue. The aim of the present study was to analyze whether mature postsurgical adhesions even after years still reveal a dynamic remodeling process.
In a prospective analysis, we investigated tissue specimen of peritoneal adhesions in 40 patients after abdominal surgery. Expression of five parameters representing wound healing and remodeling were examined (MMP-2, Ki-67, apoptosis, collagen/protein ratio, and collagen type I/III ratio).
Gender, age, and the number of previous operations had no impact on the parameters measured. Adhesion specimens were cell rich, containing mononuclear round cells, fibroblasts, adipose cells, and vascular endothelial cells. There was a positive expression of MMP-2 and apoptosis, whereas Ki-67 was marginal irrespective of adhesion maturity or quality. Adhesions classified as dense showed a significant increase in total collagen (118.2 +/- 4.9 microg/mg) and collagen type I/III ratios (3.9 +/- 0.2), whereas there were no significant differences regarding the adhesion maturity.
The distinct composition of cellular components as well as of extracellular matrix proteins may reflect an interactive cross-talk between adhesion- and stroma-derived cells even in mature adhesions. Our findings support the hypothesis that the disabilities of appropriate repair of the peritoneal surface leading to persistent adhesions are a consequence of a permanent process of disturbed remodeling.
Langenbeck s Archives of Surgery 02/2008; 393(1):59-66. · 1.81 Impact Factor
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ABSTRACT: Laparoscopic mesh-reinforcement of the hiatal region in the treatment of gastroesophageal reflux disease (GERD) and paraesophageal hernia (PEH) reduces the risk of recurrence. However, there are still controversies about the technique of mesh placement, shape, structure and material. We therefore compared tissue integration and scar formation after implantation of two different polypropylene-meshes in a rabbit model.
A total of 20 female chinchilla rabbits were included in this study. Two different meshes (Polypropylene PP, Polyglecaprone 25 Composite PP-PG) were implanted on the abdominal diaphragm around the oesophagus. After 3 months the implanted meshes were excised en-bloc. Histological and morphological analyses were carried out accordingly proliferation rate, apoptosis and collagen type I/III ratio.
Regarding proliferation rate of oesophagus PP (9.31 +/- 3.4%) and PP-PG (13.26 +/- 2.54%) differ in a significant (p = 0.0097) way. In the diaphragm we found a significant (p = 0.00066) difference between PP (9.43 +/- 1.45%) and PP-PG (18.73 +/- 5.92%) respectively. Comparing oesophagus and diaphragm we could prove a significant difference within PP-PG-group (p = 0.0195). Within PP-group the difference reached no statistical significance (p = 0.88). We found analogous results regarding apoptosis.Furthermore, there is a significant (p = 0.00013) difference of collagen type I/III ratio in PP-PG (12.28 +/- 0.8) compared to PP (8.44 +/- 1,63) in case of oesophageal tissue. Concerning diaphragm we found a significant difference (p = 0.000099) between PP-PG (8.85 +/- 0.81) and PP (6.32 +/- 1.07) as well.
The histologic and morphologic characteristics after prosthetic enforcement of the hiatus in this animal model show a more distinct tissue integration using PP-PG compared to PP. Additionally, different wound healing and remodelling capability influence tissue integration of the mesh in diaphragm and oesophagus.
BMC Surgery 02/2008; 8:7. · 1.33 Impact Factor
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ABSTRACT: Matrix metalloproteinase-2 (MMP-2, gelatinase A) plays an essential role in angiogenesis, inflammation, and fibrosis. These processes are critical for wound healing and accordingly elevated levels of MMP-2 expression have been detected after skin injury. Our goal was to investigate the transcriptional activation of the MMP-2 gene in a model of skin injury by using two different MMP-2/LacZ-reporter mice. Upon skin injury MMP-2 expression was upregulated, whereas tissue from normal skin stained negative except for occasional macrophages, sweat glands, and hair follicles. Skin injury also activated MMP-2 proteolytic activity and reporter gene expression. We demonstrate that MMP-2 regulatory sequences -1686/+423 drive appropriate injury-induced MMP-2-promoter activation. Reporter gene expression was predominantly detectable in endothelial cells and in macrophages. Deletion of the 5' responsive element, denoted RE-1, residing at -1241/+423 bp of the regulatory sequence led to abrogated MMP-2 transcription in vivo. The findings define a crucial role for the enhancer element RE-1 in injury-induced MMP-2 transcription of the skin.
Journal of Investigative Dermatology 08/2007; 127(7):1762-7. · 6.31 Impact Factor
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ABSTRACT: Matrix metalloproteinase-2 (MMP-2) is a key regulator in wound healing that orchestrates tissue remodeling. In the present study the spatial and temporal distribution of MMP-2 gene transcription, protein synthesis, and enzymatic activity were analyzed following polymeric mesh (polyglactin, polypropylene) implantation in transgenic reporter mice harboring MMP-2 regulatory sequences -1686/+423 or -1241/+423. Polymers induced MMP-2 promoter activity in macrophages within the foreign body granuloma via sequences -1686/+423 with concomitantly up-regulated protein synthesis and enzymatic activity. Macrophages distant from mesh filaments exhibited low MMP-2 expression levels. Fibroblasts surrounding mesh material displayed strong MMP-2 gene transcription independent of the included promoter sequences, whereas fibroblasts without close contact to mesh material had low MMP-2 synthesis rates due to silencing activity of sequences -1686/-1241. In vitro studies support a cellular crosstalk concept, as macrophages trans-repressed MMP-2 gene transcription in fibroblasts. The zonal and cell-specific regulation of MMP-2 gene transcription illuminates an intimate cellular crosstalk in foreign body reaction that may provide a new approach for mesh modification.
The FASEB Journal 05/2007; 21(4):1047-57. · 5.71 Impact Factor
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ABSTRACT: Intraperitoneal tumor cell attachment after resection of gastrointestinal cancer may lead to a developing of peritoneal carcinosis. Intraabdominal application of phospholipids shows a significant decrease of adhesion formation even in case of rising tumor cell concentration.
In experiment A 2*106 colonic tumor cells (DHD/K12/Trb) were injected intraperitonely in female BD-IX-rats. A total of 30 rats were divided into three groups with treatments of phospholipids at 6% or 9% and the control group. In experiment B a total of 100 rats were divided into ten groups with treatments of phospholipids at 9% and the control group. A rising concentration of tumor cells (10,000, 50,000, 100,000, 250,000 and 500,000) were injected intraperitonely in female BD-IX-rats of the different groups. After 30 days, the extent of peritoneal carcinosis was determined by measuring the tumor volume, the area of attachment and the Peritoneal Cancer Index (PCI).
In experiment A, we found a significant reduction (control group: tumor volume: 12.0 +/- 4.9 ml; area of tumor adhesion: 2434.4 +/- 766 mm2; PCI 28.5 +/- 10.0) of peritoneal dissemination according to all evaluation methods after treatment with phospholipids 6% (tumor volume: 5.2 +/- 2.2 ml; area of tumor adhesion: 1106.8 +/- 689 mm2; PCI 19.0 +/- 5.0) and phospholipids 9% (tumor volume: 4.0 +/- 3.5 ml; area of tumor adhesion: 362.7 +/- 339 mm2; PCI 13.8 +/- 5.1). In experiment B we found a significant reduction of tumor volume in all different groups of rising tumor cell concentration compared to the control. As detected by the area of attachment we found a significant reduction in the subgroups 1*104, 25*104 and 50*104. The reduction in the other subgroups shows no significance. The PCI could be reduced significantly in all subgroups apart from 5*104.
In this animal study intraperitoneal application of phospholipids resulted in reduction of the extent of peritoneal carcinomatosis after intraperitoneal administration of free tumor cells. This effect was exceptionally noticed when the amount of intraperitoneal tumor cells was limited. Consequently, intraperitoneal administration of phospholipids might be effective in reducing peritoneal carcinomatosis after surgery of gastrointestinal tumors in humans.
BMC Cancer 02/2007; 7:104. · 3.01 Impact Factor
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ABSTRACT: Collagens belong to the most abundant proteins in the body. After tissue injury, a coordinated regulation of collagen gene expression guides the formation of a provisional matrix that subsequently evolves into a mature scar with tensile strength. In the following, knowledge regarding collagen gene regulation that may provide insight into how to specifically address the biological problem of soft tissue weakness and recurrent hernia disease is summarized.
Hernia 01/2007; 10(6):486-91. · 1.84 Impact Factor
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ABSTRACT: Estrogens are reported to increase type I and type III collagen deposition and to regulate Metalloproteinase 2 (MMP-2) expression. These proteins are reported to be dysregulated in incisional hernia formation resulting in a significantly decreased type I to III ratio. We aimed to evaluate the beta-estradiol mediated regulation of type I and type III collagen genes as well as MMP-2 gene expression in fibroblasts derived from patients with or without history of recurrent incisional hernia disease. We compared primary fibroblast cultures from male/female subjects without/without incisional hernia disease.
Incisional hernia fibroblasts (IHFs) revealed a decreased type I/III collagen mRNA ratio. Whereas fibroblasts from healthy female donors responded to beta-estradiol, type I and type III gene transcription is not affected in fibroblasts from males or affected females. Furthermore beta-estradiol had no influence on the impaired type I to III collagen ratio in fibroblasts from recurrent hernia patients.
Our results suggest that beta-estradiol does not restore the imbaired balance of type I/III collagen in incisional hernia fibroblasts. Furthermore, the individual was identified as an independent factor for the beta-estradiol induced alterations of collagen gene expression. The observation of gender specific beta-estradiol-dependent changes of collagen gene expression in vitro is of significance for future studies of cellular response.
BMC Cell Biology 02/2006; 7:36. · 2.59 Impact Factor
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ABSTRACT: Adhesion of tumor cells to mesothelial cells or extracellular matrix components is a pivotal step in developing peritoneal dissemination after gastric cancer. As phospholipids were found to reduce adhesion formation, especially at sites of peritoneal lesions, we assessed the inhibition of attachment of NUGC-4 gastric cancer cells by local treatment with phospholipids to the peritoneum in nude mice. Gastric cancer cells (1xl0(6)) suspended in either normal saline (controls) or phospholipid suspension 75 mg/kg body weight (PL75) or 150 mg/kg (PL150) were injected intraperitoneally into 90 female BALB/c nu/nu mice. The treatment groups were subdivided into animals with defined peritoneal lesions and animals without lesions. After 30 days the extent of peritoneal carcinosis and the Peritoneal Cancer Index were evaluated. Statistical analysis was performed with two factorial ANOVAs. The level of significance was adjusted according to Bonferrorni (alpha = 0.00278). During a 90-day observation period the survival rate was determined using the log rank test. After 30 days the intraperitoneal tumor volume was reduced by PL150 up to 0.6 ml (SEM 0.16) and 0.48 ml (SEM 0.09) in mice with peritoneal lesions compared to 0.9 ml (SEM 0.2) and 0.9 ml (SEM 0.1) in the control group (P = 0.04). The mean area of tumor adhesion amounted to 145 mm(2) (SEM 17) (P = 0.08) and 164 mm(2) (SEM 32.8) (P = 0.049) with peritoneal lesions after treatment with PL150 [controls: 216 mm(2) (SEM 28.5) and 245 mm(2) (SEM 29.3)]. The peritoneal cancer index was 16.4 (SEM 1.7) in the control group and 9 (SEM 1.68) with PL150 (P = 0.0002). In the subgroup with peritoneal lesions, the respective values were as follows: controls: 20.8 (SEM 0.85); PL 150:14.3 (SEM 1.07) (P = 0.0001). We found a prolonged survival rate after treatment with PL150. However, this effect was not significantly different to that seen in the control group. Treatment with PL75 had no significant influence. Phospholipids may be an efficacious and economic tool for reducing peritoneal tumor cell adhesion and consequently the development of peritoneal carcinosis after resection of gastric cancer.
World Journal of Surgery 07/2005; 29(6):708-14. · 2.36 Impact Factor
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ABSTRACT: To evaluate the influence of intraperitoneal treatment with phospholipids on the formation of peritoneal carcinosis after inoculation of colonic tumor cells in rats. The presence of tumor cells in the peritoneal cavity serves as a prognostic marker for postoperative survival after resection of gastrointestinal cancer. Intraperitoneal tumor cell attachment is a pivotal step in developing peritoneal carcinosis. Intraabdominal application of phospholipids resulted in a significant decrease of adhesion formation, especially at sites of peritoneal lesions.
2x10(6) colonic tumor cells (DHD/K12/TRb) were injected intraperitonely in female BD-IX rats. A total of 90 rats were divided into three groups with treatments of phospholipids at 75 mg/kg or 150 mg/kg bodyweight or sodium chloride at 0.9% in the control group. The treatment groups were subdivided into animals with defined peritoneal lesions and animals without lesions. After 30 days, the extent of peritoneal carcinosis was determined by measuring the tumor volume, the area of tumor attachment and the Peritoneal Cancer Index. Over a 90-day observation period, the survival rate was analyzed. In vitro, we examined the reduction of tumor cell adhesion on extracellular matrix components after treatment with phospholipids. Microtiter plates were coated with laminin, fibronectin or collagen IV for adhesion experiments.
In our study, we found a significant reduction of peritoneal dissemination with respect to all evaluation methods after treatment with phospholipids at 150 mg/kg in animals without peritoneal lesions. This could not be achieved using the lower concentration of phospholipids (75 mg/kg). In vitro, the maximum reductions of tumor cell adhesion by phospholipids compared with the control values for laminin and fibronectin were 46% and 37%, respectively, whereas for collagen IV the reduction was only 24% ( p<0.0001).
A new method of prevention of intraperitoneal tumor cell adhesion, possibly leading to a reduced incidence of peritoneal carcinosis after surgery of gastrointestinal tumors, is introduced.
International Journal of Colorectal Disease 12/2004; 19(6):525-32. · 2.38 Impact Factor
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ABSTRACT: Nidation of floating tumour cells initiates peritoneal carcinosis and limits prognosis of gastro-intestinal tumours. Adhesion of tumour cells to extracellular matrix components is a pivotal step in developing peritoneal dissemination of intraabdominal malignancies. Since phospholipids efficaciously prevented peritoneal adhesion formation in numerous animal studies we investigated their capacity to reduce adhesions of gastric cancer cells to extracellular matrix components (ECM).
Human gastric cancer cells (NUGC-4, Japanese Cancer Research Resources Bank, Tokyo, Japan) were used in this study. Microtiter plates were coated with collagen IV (coll), laminin (ln) and fibronectin (fn). Non-specific protein binding of the coated wells was blocked by adding 1% (w/v) BSA (4 degrees C, 12 h) and rinsing the wells with Hepes buffer. 50.000 tumour cells in 100 microl medium were seeded into each well. Beside the controls, phospholipids were added in concentrations of 0.05, 0.1, 0.5, 0.75 and 1.0/100 microl medium. After an incubation interval of 30 min, attached cells were fixed and stained with 0.1% (w/v) crystal violet. The dye was resuspended with 50 microl of 0.2% (v/v) Triton X-100 per well and colour yields were then measured by an ELISA reader at 590 nm. Optical density (OD) showed a linear relationship to the amount of cells and was corrected for dying of BSA/polystyrene without cells.
The attachment of gastric cancer cells to collagen IV, laminin, and fibronectin could be significantly reduced up to 53% by phospholipid concentrations of 0.5 mg/100 microl and higher.
These results, within the scope of additional experimental studies on mice and rats which showed a significant reduction of peritoneal carcinosis, demonstrated the capacity of phospholipids in controlling abdominal nidation of tumour cells to ECM components. Lipid emulsions may be a beneficial adjunct in surgery of gastrointestinal malignancies.
BMC Gastroenterology 02/2004; 4:33. · 2.42 Impact Factor
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ABSTRACT: The multifunctional DNA- and RNA-associated Y-box protein 1 (YB-1) specifically binds to splicing recognition motifs and regulates alternative splice site selection. Here, we identify the arginine/serine-rich SRp30c protein as an interacting protein of YB-1 by performing a two-hybrid screen against a human mesangial cell cDNA library. Co-immunoprecipitation studies confirm a direct interaction of tagged proteins YB-1 and SRp30c in the absence of RNA via two independent protein domains of YB-1. A high affinity interaction is conferred through the N-terminal region. We show that the subcellular YB-1 localization is dependent on the cellular SRp30c content. In proliferating cells, YB-1 localizes to the cytoplasm, whereas FLAG-SRp30c protein is detected in the nucleus. After overexpression of YB-1 and FLAG-SRp30c, both proteins are co-localized in the nucleus, and this requires the N-terminal region of YB-1. Heat shock treatment of cells, a condition under which SRp30c accumulates in stress-induced Sam68 nuclear bodies, abrogates the co-localization and YB-1 shuttles back to the cytoplasm. Finally, the functional relevance of the YB-1/SRp30c interaction for in vivo splicing is demonstrated in the E1A minigene model system. Here, changes in splice site selection are detected, that is, overexpression of YB-1 is accompanied by preferential 5' splicing site selection and formation of the 12 S isoform.
Journal of Biological Chemistry 06/2003; 278(20):18241-8. · 4.77 Impact Factor
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ABSTRACT: Peridural analgesia (PDA) is a common treatment in postoperative management after abdominal surgery to shorten postoperative ileus and to permit early postoperative nutrition. There are conflicting opinions on the effect of early peristalsis on healing of colonic anastomoses.
A short segment of the distal colon was resected in 32 Wistar rats. Two strain gauge transducers were placed on the serosa proximal to the anastomosis to measure the strength and periodicity of bowel contractions. A peridural catheter was placed between lumbar vertebra 7 and the sacral crest. The animals received 4, 16, 20, and 24 h after operation an injection of either 0.03 ml ropivacaine 0.75%/kg body weight or the same amount of sodium chloride (controls). After 3 and 10 days the colonic anastomoses were resected to measure the bursting pressure. The anastomoses were prepared for histopathological examination and determination of relative collagen content.
Postoperative PDA led to an increasing amplitude of phasic and tonic contractions while the frequency of contractions was not significantly affected. None of the groups presented with any anastomotic complications. The bursting pressure after 3 and 10 days was similar in the two groups. The relative amount of collagen I in the anastomotic area was significantly higher after treatment with peridural ropivacaine.
Postoperative PDA with ropivacaine increases the strength of colonic contractions. The increase in phasic contractions suggests a better propulsive bowel function. The significantly higher amount of collagen I in the anastomosis of animals in the PDA group supports the idea that healing of colonic anastomoses is improved rather than diminished by PDA.
International Journal of Colorectal Disease 02/2003; 18(1):50-4. · 2.38 Impact Factor
