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R Rosch

Publications and source records attributed to R Rosch.

33 records · Page 2Linked to original sources
PubMed2002

[Weakly malignant leiomyosarcoma of the inferior vena cava. A case report].

Primary vascular leiomyosarcomas of the great vessels are rare and the most common localization is the inferior vena cava. Due to nonspecific clinical signs, diagnosis is often made during operation or autopsy. At present, a radical tumor resection is the first choice of treatment. This is a case report of a 49-year-old woman who suffered from abdominal pain for 10 years because of a weakly malignant leiomyosarcoma of the inferior vena cava. A radical tumor resection and reconstruction with a prosthetic vascular graft were performed. Diagnosis, therapy, and prognosis are discussed.

Blood Vessel Prosthesis Implantation↗
PubMed2002

[Retromuscular mesh repair for ventral incision hernia in Germany].

Since the onset of an incisional hernia is caused by the biological problem of forming stable scar tissue, the mesh techniques are now the methods of choice for incisional hernia repair. Polypropylene is the material most widely used for open mesh repair. New developments have led to low-weight, large-pore polypropylene prostheses, which have been adapted to the physiological requirements of the abdominal wall and permit a reliable tissue integration. These meshes make it possible for a scar net to form rather than a stiff scar plate, thus helping to avoid the complications encountered with the use of earlier meshes. The ideal position for the mesh seems to be the retromuscular underlay position, in which the force of abdominal pressure holds the prosthesis tightly against the deep surface of the muscles. The retromuscular underlay repair technique has yielded the lowest incidence rates for recurrence: around 10% even after long-term follow up. Analysis of the failures after open mesh repair suggests that inadequate size of the mesh with insufficient overlap at the edges is the main reason for recurrence. An overlap of at least 5-6 cm all round must therefore be considered mandatory for successful reinforcement of the abdominal wall. Open mesh repair, particularly with modern low-weight polypropylene meshes applied by the retromuscular underlay technique, offers excellent results in the treatment of incision hernias, even in long-term follow-up studies.

Abdominal Wall↗
PubMed2002

[Prevention of incisional hernia].

Incisional hernia is the most frequent late complication of surgery; its incidence is constant and it has a high socio-economic impact. Possible preventive measures are analysed in this article on the basis of current clinical and experimental findings. An argument that is restricted strictly to the surgical and technical aspects does not do justice to the complexity of incisional hernia development. It has been proved that continuous mattress suturing after laparotomy is beneficial in terms of wound healing and also means significantly shorter operating times and smaller amounts of suture material are needed. Combined with a suture length-to-wound length ratio of at least 4:1, this technique is superior to single interrupted suturing as its bio-mechanical properties are better and it allows better collagen synthesis in the region of the incision. It is not possible to recommend any one particular suture material at present. The possibilities of influencing the endogenous risk factors connected with the patient and any co-morbidity is hampered by economic aspects and low efficiency, although precisely such endogenous factors have a high potential for influencing treatment in the future. Suture tension is a relevant parameter that has not yet been sufficiently fully evaluated. Better monitoring of suture tension might open up the possibility of devising new variants of laparotomy closure techniques that would reduce the incidence of incisional hernias. In view of the significance of impaired wound healing for the surgical specialties, suture tension and the search for possible ways of influencing and modulating collagen synthesis look like promising topics that would reward a more intense research effort in the future.

Hernia, Ventral↗
PubMed2000

Short- and long-term results after laparoscopic vs conventional colon resection in a tumor-bearing small animal model.

BACKGROUND: We designed a study to evaluate the short- and long-term outcome of laparoscopic vs conventional colonic resection in a tumor-bearing small animal model. METHODS: We operated on male BD X rats (260-300 g), performing either laparoscopic (n = 9) or open colon resection (n = 9) in order to evaluate stress and immunological response to laparoscopic vs conventional colon resection. A third group (n = 9) underwent anesthesia only. Immediately before and after surgery, as well as at 1, 7, and 21 days postoperatively, a sample of 1 ml blood was taken from the retrobulbar venous plexus. Stress (corticosterone) and immune parameters (neopterine and IL-1 beta, IL-6) and body weight as a parameter of postoperative recovery were measured to identify short-term alterations. Long-term changes were evaluated in terms of survival time and at autopsy by measuring the tumor weight and the number of tumor infiltrated nodules (histology). RESULTS: The analysis of variance (ANOVA) showed significant differences between the three groups over a period of 1 week (p < 0.001 for corticosterone, p = 0.009 for neopterine, p = 0.04 for IL-1 beta, p = 0.024 for IL-6). Additionally, significant differences by t-test were found between the laparoscopic (minor alteration) and conventional (major alteration) group regarding corticosterone (p = 0.0015), neopterine (p = 0.0024), IL 1-beta (p = 0.033), and IL-6 (p = 0.015) at the end of the operation. One week after the operation, the body weight was different depending on the type of operative procedure: 7 days postoperatively the rats lost 8% of their body weight after open surgery but only 4.3% after laparoscopic surgery. After anesthesia only, body weight increased by approximately 4.8%. The medium survival time for the lap group was 44 days, whereas it was 44.1 days for the conventional group and 46 days for the anesthesia group (ANOVA p = 0.625). The number of nodules was 13.5 in the laparoscopic group 10.5 in the open group, and 7.4 in the anesthesia group, (ANOVA p = 0.119). The tumor weight was 6.8 g in the laparoscopic group, 6.4 g in the open group, and 5.04 g in the anesthesia group (ANOVA p = 0.874). CONCLUSION: In a tumor-bearing small animal model, laparoscopic colon resection alters the stress and immune system less than open colon resection. This observation has no implications for the long-term results as measured by survival time and at autopsy. Therefore, laparoscopic colon resection has a short-term benefit and has no negative effect on long-term results compared to conventional operative procedures.

Adenocarcinoma↗
PubMed2000

Effect of pressure and gas type on intraabdominal, subcutaneous, and blood pH in laparoscopy.

BACKGROUND: According to the literature, the number of port-site metastases in laparoscopic surgery varies considerably depending on the type of gas used for the pneumoperitoneum. In order to investigate this observation we studied the changes in blood, subcutaneous, and intra-abdominal pH during laparoscopy with helium, CO(2) and room air in a rat model. In addition, we looked at the influence of intra-abdominal pressure and duration of pneumoperitoneum on the pH during the laparoscopy. METHODS: pH was measured by tonometry, intra-abdominally and subcutaneously. A pH electrode was additionally placed into the subcutaneous tissue and the results compared to those measured by tonometry. Blood samples were taken from a catheter in the carotid artery. The intra-abdominal pressure was 0, 3, 6, 9 mm Hg for 30 min in each case. We investigated the effect of pneumoperitoneum with CO(2), helium and air in randomized groups of 5 rats. In an additional series the pressure was held constant at 3 mm Hg and the pH was measured every 30 min. RESULTS: Due to the different absorption capacity of the peritoneum, laparoscopy with CO(2) decreases the subcutaneous pH from 7.35 to 6.81. Blood pH is reduced from 7.37 to 7.17 and the intra-abdominal pH from 7.35 to 6.24. Other, less absorbable gases induce smaller changes of blood and subcutaneous pH (only 10% of CO(2)). In a variance analysis the p value is less than 0.001. The influence of duration of laparoscopy (30 min vs. 90 min) on the subcutaneous pH is less compared to the influence of intra-abdominal pressure (0, 3, 6, 9 mm Hg). CONCLUSIONS: Depending on the type of gas (CO(2), air, helium) used for laparoscopy blood, subcutaneous and intra-abdominal pH are influenced differently. Because lower pH is known to impair local defense mechanisms, these results may be one explanation for the higher incidence of port-site metastasis in laparoscopy with CO(2) than with other gases, as reported in the literature.

Abdomen↗
PubMed1994

Protein S in end stage liver disease and in the course of liver transplantation.

Protein S (PS) is mainly synthesized in the liver and in endothelial cells. Determination of PS levels is complicated by the fact that total PS antigen (total PS Ag) exists in plasma as free and functionally active protein (free PS Ag) and in a reversible inactive complex with C4b-binding protein. In blood samples from patients with end stage liver diseases we studied PS levels before, during and after orthotopic liver transplantation (OLT). Median levels of total and free PS Ag were below and within the lower part of the reference interval, respectively. Two different groups in PS distribution could be distinguished. In 70% of the patients with preoperative levels of total and free PS Ag within the reference interval showed an impaired free/total PS Ag ratio towards higher unbound and free PS Ag levels. With reperfusion of the graft liver total and free PS Ag decreased significantly and the free/total PS Ag ratio normalized. In 30% of the patients reduced PS Ag levels together with a normal free/total PS Ag ratio were seen. In the reperfusion phase no further reduction of total and free PS Ag could be observed.

Adult↗
PubMed1994

Thrombomodulin: a marker for endothelial damage during orthotopic liver transplantation.

Thrombomodulin is a surface protein of vascular endothelial cells. A smaller form of thrombomodulin in blood and urine, the soluble (s)thrombomodulin, appears to be derived from injured endothelial cells or to be proteolytically cleaved from thrombomodulin by proteases. Several in vitro and in vivo studies have suggested (s)thrombomodulin as a marker of endothelial damage. In orthotopic liver transplantation, platelet and leukocyte activation as well as prothrombin activation are suspected of being caused by damaged endothelial cells in the graft liver. We determined (s)thrombomodulin antigen as well as thrombin-antithrombin III complexes, protein C, and antithrombin III activities in the course of 23 orthotopic liver transplantations. Samples were taken at 7 different time-points intraoperatively, as well as out of the perfusate released from the graft liver vein during the flushing procedure with arterial blood prior to the opening of the hepatocaval anastomosis. Levels of (s)thrombomodulin antigen and thrombin-antithrombin III complexes showed a significant increase with reperfusion of the graft liver and levels in the perfusate were higher (both: P = 0.0001) than the corresponding systemic levels. In parallel, antithrombin III decreased significantly with reperfusion and perfusate levels of antithrombin III and protein C activities were lower in the systemic circulation (both: P = 0.0001). In conclusion, high levels of (s)thrombomodulin antigen in the early reperfusion phase and in the perfusate strongly indicate endothelial damage to the graft liver vascular bed, paralleled and followed by signs of prothrombin activation.

Antigens↗
PubMed1975

[Hospitalized hypertensiol patients with gastrointestinal disease].

A careful codification according to the rules of electronic data processing of all data given and especially of the admission number on the signature margin of th medical record gives the possiblity of a rapid return of information for the practice and of a scientific evalustion. 404 patients with hypertension (400-404) of the distric Rostock who were treated in the clinic simultaneously suffered from gastrointestinal diseases (531-536, 570-577). For a more specialized analysis of the clinical data from case histories the four largest institutions of the district were chosen. From this results a relation number of 100 patients with these diagnostic combinations. 73% of these patients were of female sex. The higher blood pressure values at the beginning of the treatment we find in hypertensive patients with simultaneous disease of the gallbladder, in which cases these patients to 44% also showed an overweight. In 74% of the patients there occurred a systolic decrease of blood pressure, in 66% a diastolic one. More frequently than on the average the decrease of the blood pressure appeared in patients with liver and gall-bladder diseases.

Adult↗
PubMedDate not supplied

Influence of mesh materials on collagen deposition in a rat model.

Alterations of the extracellular matrix (ECM) with its major component collagen are increasingly discussed as possible risk factors implicated in the development of abdominal-wall herniation. Because of the widespread use of alloplastic meshes for the surgical repair of hernias, an animal study was performed to analyze the influence of various mesh materials on the quantity and quality of collagen deposition. In 60 male Sprague-Dawley rats an abdominal replacement was performed using three different kinds of mesh materials: polyester (PE), a pure polypropylene (PP), and a composite mesh made of polypropylene and polyglactin (PG). A simple fascia suture repair served as control. The count of fibroblasts, the collagen/protein ratio, the type I/III collagen ratio, and the expression of basic fibroblast growth factor (b-FGF) at the interface were analyzed after 7, 21, and 90 days. The ratio of collagen to overall protein (microg/mg) showed significant differences comparing different mesh materials (sham controls 38.44 +/- 16.33 microg/mg, PE 68.5 +/- 23.8 microg/mg, PP 101.6 +/- 32.3 microg/mg, PG 49.6 +/- 11.6 microg/mg at day 90). The ratio of collagen type I/III increased over time in all groups. However, 90 days after mesh implantation the ratio was always significantly lowered compared to the controls. No significant difference was found comparing different mesh materials. The alteration of the scar composition is closely connected to an increased b-FGF expression. b-FGF and count of fibroblasts highly correlated (r =.95) and showed significant elevated levels compared to simple suture repair. The results of our study strongly support the notion that wound healing is affected by mesh implantation. The quality of the ECM deposition as determined by collagen type I/III ratio is impaired in general, whereas the quantity of ECM deposition is markedly influenced by the kind of mesh material.

Animals↗
PubMedDate not supplied

Influence of pneumoperitoneum on small bowel anastomoses: a histological analysis in the rat model.

Laparoscopic techniques are increasingly applied for the treatment of diverse gastrointestinal diseases. With regard to reports of a pronounced decrease of intra-abdominal blood flow with increasing intra-abdominal pressure, the present study investigates the impact of pressure and gas type on ischemia in small bowel anastomoses in the rat model. Laparotomy and ileoileal anastomosis were performed in 39 male Sprague-Dawley rats. A CO2 or helium pneumoperitoneum of 3 mm Hg or of 6 mm Hg was maintained before and after anastomoses. Rats in the control group received no pneumoperitoneum. Animals were sacrificed after 5 d, and the anastomotic region was explanted for subsequent histopathological examinations. In hematoxylin and eosin (HE)-stained sections, the Chiu score, villi configuration, and number of goblet cells were analyzed. Proliferation (Ki67) and expression of a matrix metalloproteinase (MMP-8) were examined by immunohistochemistry. Mucosal damage according to the scoring system by Chiu, the number of goblet cells, the villus length, the proliferation (Ki67), and the submucosal expression of MMP-8 was similar in all groups. Our results suggest that within a certain range of pressures and time, laparoscopic assisted surgery using CO2 pneumoperitoneum can be performed safely. Helium gas offers no advantages over CO2.

Anastomosis, Surgical↗
PubMedDate not supplied

Pathophysiologic role of contact activation in bleeding followed by thromboembolic complications after implantation of a ventricular assist device.

The time period after implantation of a ventricular assist device in patients with end-stage heart disease is complicated by hemorrhage in the early postoperative period and by thromboembolism in the later course. To investigate the pathophysiologic role of contact activation in 12 bridging patients (10 patients with a paracorporeal Berlin Heart [Berlin Heart GmbH, Berlin, Germany], 2 patients with an intracorporeal Novacor system [Novacor N100; Baxter, Oakland, CA]), hemostatic parameters were determined until heart transplantation or at least up to the 51st postoperative day. The following were observed: 1) In the early postoperative period, until day 15, levels of contact factors XI, XII, and prekallikrein were below normal, whereas levels of plasmin-a2-antiplasmin (PAP) complexes were elevated. Thrombin-antithrombin III (TAT) complexes, as well as platelet factor 4 and beta-thromboglobulin, significantly increased immediately after surgery. 2) In the later postoperative period, starting with the third postoperative week, an increase of factors XI, XII, and prekallikrein was observed. PAP and TAT complexes, as well as platelet factor 4 and beta-thromboglobulin, remained elevated. It is concluded that, in the early postoperative period, hemostasis is influenced mainly by an activation of the intrinsic contact system dependent fibrinolytic system with consumption of contact factors and increased levels of PAP complexes, whereas later system dependent fibrinolysis becomes less important, leading to a shift of the balance toward coagulation, with sustained prothrombin and platelet activation. This is in accord with the observed clinical complications (e.g., early postoperative bleeding, and thromboembolic events later on).

Adult↗
PubMedDate not supplied

Mesh implants in hernia repair. Inflammatory cell response in a rat model.

BACKGROUND: In the reinforcement of the abdominal wall with mesh implants, various complications including hernia recurrence, abdominal pain, seroma formation and infection are discussed to depend on the biocompatibility of the alloplastic prosthesis. Particularly macrophages, T-cells and mast cells have been shown to play a major role in the inflammatory response to biomaterials. To approach biocompatibility of surgical meshes we therefore examined the infiltrate of these cells as well as the proliferation rate in response to different clinically applied materials. MATERIALS AND METHODS: Three mesh materials (polypropylene: PP, Prolene; polyethylene terephthalate: PET, Mersilene, and polypropylene/polyglactin: PP + PG, Vypro) were compared after inlay implantation in a standardized rodent animal model. A suture-closed laparotomy served as control. After 7 and 90 days of implantation, histochemical analysis of the inflammatory response to all biomaterials was performed: macrophages (ED3), T-cells (CD3), proliferating cells (PCNA) and mast cells (Giemsa) were investigated. RESULTS: In all groups a persisting T-cell response was observed. Colonization of the interface with macrophages showed a pronounced reduction in the PP + PG-mesh group. Infiltration of mast cells at the tissue graft interface showed a time-dependent decrease in the PET- and PP + PG-mesh groups, whereas in contrast, index of mast cells increased in the PP-mesh group. At both time points, indices of proliferation were highest in the PP-mesh group. CONCLUSION: The present data confirm the development of a biomaterial-dependent chronic inflammatory response to surgical meshes with macrophages as the predominant cell type. Further research on the recruitment of inflammatory cells and in particular on the role of mast cells and their granular products should be encouraged.

Animals↗
PubMedDate not supplied

Vypro II mesh in hernia repair: impact of polyglactin on long-term incorporation in rats.

BACKGROUND: To the Vypro II mesh, a large-pore-sized multifilamentous polypropylene mesh for hernia repair, supplementary polyglactin 910 multifilaments were added to improve intraoperative handling. As it has been suggested that polyglactin induces fibroplastic reactions and wound complications, this study was designed to evaluate the long-term tissue reaction to polyglactin in the Vypro II mesh. MATERIALS AND METHODS: Two mesh materials, the Vypro II composite mesh (PP + PG) and the pure polypropylene variant (PP), were compared after inlay implantation in a standardized rodent animal model. After 14, 28, 42, 56, 84 and 112 days of implantation, histological analysis of the inflammatory response was performed: material absorption, inflammatory tissue reaction, fibrosis and granuloma formation were investigated. RESULTS: Total absorption of polyglactin filaments of the Vypro II mesh occurred between 56 and 84 days of implantation. Both the inflammatory and the fibrotic reaction were initially increased in the PP + PG mesh group. These differences disappeared in the following implantation period. After 112 days, inflammation was even less pronounced in the PP + PG mesh group. CONCLUSION: The present data confirm a short-term polyglactin-induced increase in inflammation and fibrosis around implanted Vypro II meshes in rats. With regard to the long-term tissue response, even an anti-inflammatory property of polyglactin multifilaments in low-weight and large-pored polypropylene meshes cannot be ruled out.

Absorption↗
PubMedDate not supplied

Persistent extracellular matrix remodelling at the interface to polymers used for hernia repair.

On the one hand, recurrence rates and postoperative complications following hernia repair are supposed to be influenced by the kind of mesh material used. On the other hand, an impaired collagen metabolism and cleavage within connective tissue has been suggested as decisive factor in the pathogenesis of recurrent hernia formation. The aim of our study was, therefore, to analyze the impact of commonly used mesh materials on quality of collagen deposition, expression of collagenases (matrix metalloproteinases; MMP-1/MMP-13), and specific tissue inhibitors of MMPs (TIMPs) in an animal study. Four different mesh materials were used (Prolene = polypropylene, Mersilene = polyester, and Vypro and Vypro II = combinations of polypropylene and polyglactin) and implanted as abdominal wall replacement in 60 male Wistar rats. Mesh samples were explanted after 3, 21, and 90 days and investigated using immunohistochemistry (expression of MMP-1/MMP-13 and TIMP-1) and cross-polarization microscopy (percentage of collagen type III to overall collagen). Besides an insufficient collagen composition with an increased percentage of collagen type III, we found a complex expression of collagenases and their inhibitors combined with a persistent chronic foreign-body reaction even 90 days after implantation. Except for TIMP-1 expression, which was significantly related to a lowered amount of inflammatory (r = -0.980, p = 0.02) and connective tissue formation (r = -0.951, p = 0.049), there was no relation to the expression of collagenases (MMP-1/MMP-13) with regard to the amount of inflammatory and connective tissue formation despite partly significant differences between implanted polymers.

Animals↗