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Biomedical subjects

U Klinge

Publications and source records attributed to U Klinge.

At least 91 records · Page 5Linked to original sources
PubMed1999

Synthesis of type I and III collagen, expression of fibronectin and matrix metalloproteinases-1 and -13 in hernial sac of patients with inguinal hernia.

Since many years the importance of a weakness of the soft tissue for the development of hernias is discussed controversially. The tensile strength of the tissue is supposed to depend largely on the varying proportion of type I collagen with its high tensile strength and the immature type III collagen. Their relation is regulated by several collagenases, mainly matrix metalloproteinases-1 and -13 (MMP-1 and MMP-13), whereas fibronectin plays a key role for the adherence of cells within the extracellular matrix. The aim of this study was to investigate whether an alteration in type I and type III collagen synthesis, amounts of MMP-1 and MMP-13 and the expression of fibronectin were associated with the development of inguinal hernia. We analysed the hernial sac of patients with indirect (n = 9) and direct (n = 7) inguinal hernias and peritoneum in controls (n = 7) by immunohistochemistry and Western blot analysis. The results showed that the ratio of relative amount of I/III collagen was markedly decreased in patients with either indirect or direct hernias as compared with controls (p < 0.001) with a concomitant increase in type III collagen synthesis. MMP-13 was expressed neither in the hernial sac nor in the peritoneum of the controls, but the positive reactions of MMP-1 were found in the surface of the subserosa of the hernial sac in patients with indirect or direct hernias without any difference compared to controls. Furthermore, the relative amount of fibronectin in patients with either indirect or direct hernias is not significantly different from controls (p > 0.05). In regard to the known alterations of the collagen metabolism in fascia and skin of hernia patients the changed collagen I/III ratio with its increase of type III collagen in hernial sacs support the presence of a systemic disturbance of collagen metabolism. The absence of changes of the expression of collagenases (MMP-1, MMP-13) and the constant levels of fibronectin underline the central role of collagen synthesis for the development of indirect or direct hernias.

Aged↗
PubMed1998

Functional and morphological evaluation of different polypropylene-mesh modifications for abdominal wall repair.

Modern surgical hernia repair depends increasingly on synthetic meshes for the reconstruction of the abdominal wall. Despite the undisputed advantages of the polypropylene (PP) meshes currently available (Marlex, Prolene), reports of complications after implantation are increasing. Although, serious complications such as perforation and fistula formation are rare, minor and local complaints such as seromas, misfeelings and a decreased abdominal wall mobility are observed in about one-half of the patients. In regard to the exaggerated strength of the currently available mesh modifications a reduction of the material should improve the integration of the meshes into the artificial abdominal wall. In the present study, the commercially available basic mesh Prolene has been compared to two newly constructed PP-mesh modifications with reduced amounts of PP. The modifications have gradually been adopted to the physiological requirements of abdominal wall stability and mobility by reducing the amount of PP to 64% (E-BLUE) and 24% (variant A) of the Prolene mesh (developed by ETHICON, Norderstedt, Germany). All PP-mesh variants have been implanted in a rat model and studied by 3D-photogrammetry, tensiometry, light- and electron microscopy, as well as morphometry over implantation intervals of 3, 7, 14, 21 and 90 days. The data show that current constructions of PP-meshes are oversized and definitely restrict abdominal wall mobility in the present model. Sufficient stability of the artificial abdominal wall is even guaranteed by PP-mesh modifications with a reduction of PP-quantity to about 25% of the Prolene mesh. The degree of fibrosis directly correlated with abdominal wall restriction, whereas the formation of connective tissue in the interface PP-fibre/host-issue depends on the amount and activity of the inflammatory reaction. The quantity and quality of inflammation, again, directly relies to the amount of PP and to the surface area in contact with the recipient tissues. Altogether, the present study suggests that a modification of the PP-meshes could be helpful to prevent major and minor complications of surgical PP-meshes.

Abdominal Muscles↗
PubMed1998

Modified mesh for hernia repair that is adapted to the physiology of the abdominal wall.

OBJECTIVE: To develop a new mesh for hernia repair that is adapted to the physiological forces. DESIGN: Animal experiment. SETTING: Surgical Department of the RWTH-Aachen. ANIMALS: Wistar rats MAIN OUTCOME MEASURES: Textile analysis, tensile strength, bending stiffness, histology and morphometry. RESULTS: After textile analysis of commercially available meshes in clinical use we defined the physiological forces and constructed a new mesh (Soft Hernia Mesh, SHM) based on a combination of non-absorbable polypropylene and absorbable polyglactin 910. The amount of non-absorbable material could be reduced to < 30% compared with Marlex while still guaranteeing the necessary pulling force of 16 N/cm. Improvements of the hosiery structure improved the symmetrical distribution of the retaining forces in all directions. Compared with the considerable restriction of the abdominal wall mobility by Prolene (polypropylene) and Mersilene (polyester) meshes there was no increase in the bending stiffness after the implantation of the new mesh. Histological examination showed a pronounced reduction of the inflammatory reaction in the tissues, and the collagen bundles were orientated merely around the mesh filaments instead of forming a scar plate that completely embedded the mesh. CONCLUSION: Different meshes caused specific histological reactions with changes of their mechanical properties after implantation in rodents. A new mesh with a reduced amount of polypropylene showed both less inflammation and less restriction in the mobility of the abdominal wall though it exceeded the required tensile strength of 16 N/cm.

Abdominal Muscles↗
PubMed1998

Shrinking of polypropylene mesh in vivo: an experimental study in dogs.

OBJECTIVE: To assess the extent of shrinkage of meshes used for hernia repair. DESIGN: Experimental study in dogs. SETTING: University hospital, Germany and University Research Centre, Moscow. ANIMALS: 10 dogs had monofilament polypropylene meshes that weighed 95 g/m2 (Marlex) or multifilament reduced polypropylene meshes combined with polyglactin 910 that weighed 55 g/m2 (Soft Hernia Mesh) implanted for either 3 or 6 months. MAIN OUTCOME MEASURES: Histological appearance and radiological assessment of the position and area of the mesh. RESULTS: After 4 weeks the area of mesh in the monofilament group was reduced from to 139 (11) to 75 (8) cm2 (54%) and that of the multifilament from 116 (18) to 77 (20) cm2 (66%). The multifilament mesh with the reduced amount of polypropylene showed less inflammatory response and less shrinkage. The mesh did not seem to have moved. CONCLUSION: Meshes that contain a lot of polypropylene shrink to about 30%-50% of their original size after 4 weeks, requiring an overlap of at least 3 cm if implanted subfascially. Reduction in the polypropylene content decreases both the inflammatory response and the shrinkage. Meshes with big pores are less likely to fold and improve compatibility.

Animals↗
PubMed1997

[Development and pathophysiology of abdominal wall defects].

Repair of abdominal wall hernias is the most frequently performed operation in surgery. Primary hernias arise at anatomical weak points; incisional hernias result from laparotomies. As the fascia heals slowly, the suture should be strong enough to withstand the intraabdominal pressure. Complications in wound healing may lead to a hernia, especially when absorbable sutures have been used. The rate of incisional hernias is technically influenced by the type of incision, the suture technique, and the suture material. To achieve adequate repair it is often necessary to change the principles of abdominal wall closure, for example by using alloplastic material. The meshes reinforce the architecture of the abdominal wall both by pure mechanical means and by induction of a stable scar formation (polypropylene, polyester).

Abdominal Muscles↗
PubMed1997

Monocyte-biomaterial interaction inducing phenotypic dynamics of monocytes: a possible role of monocyte subsets in biocompatibility.

For the in vitro study of cell-biomaterial surface interactions, the choice of cell type is crucial. In vivo data indicate that during the healing of the implant in the tissues, the pivotal cell types are the macrophages. These cells, upon interaction with any foreign material, might initiate a spectrum of responses, which could lead to acute and chronic inflammatory changes affecting the biocompatibility of the implant. Whether the mechanisms governing the type of evolving inflammatory reaction could be attributed to the macrophages functional differentiation mirrored by monocyte subsets during the polymer interaction, is poorly described. This in vitro study, therefore, attempted to investigate whether different biomaterials influence monocyte cellular activity, determined by the myeloperoxidase level and mitochondrial XTT cleavage, and phenotype dynamics characterized by the presence of CD14, RM 3/1 and 27E10 antigens. It is shown that different polymers exert differential potential to influence monocytes, both in their cellular activity and their phenotypic pattern. Thus, these findings demonstrating material-induced monocyte activation and monocyte phenotype modulation, are suggestive of the monocyte role as reporter cells in evaluating the biocompatibility of a synthetic medical device.

Journal Article↗
PubMed1997

[Morphologic correlation of functional abdominal wall mechanics after mesh implantation].

Modern surgical hernia repair depends increasingly on synthetic meshes for reconstruction of the abdominal wall. Despite the undisputed advantages of the synthetic meshes currently available, reports of late complications after implantation are accumulating. It is essential that the synthetic meshes be improved, but this makes a standardized animal model necessary for evaluation of their biocompatibility on both functional and morphological levels. In the present study, commercially available polypropylene and polyester meshes were implanted in a rat model, and detailed morphological and morphometric analysis were carried out. Correlations between the morphological and morphometric data and the function of the artificial abdominal wall were then sought. In summary, the data show that the mesh construction currently available are oversized and definitely restrict the function of the artificial abdominal wall. The degree of inflammation and fibrosis, the pattern of fibrosis, and the composition of the extracellular matrix exert decisive influences on the function. Fibrosis and inflammation are caused less by the material itself, however, than by its density, the way it is processed, and its surface. Future, that is to say second-generated, mesh constructions should be designed with the aims of reducing the amount of material used and finding material-specific processing methods in mind, to improve the functionally and morphologically defined biocompatibility.

Abdominal Muscles↗
PubMed1996

[Changes in abdominal wall mechanics after mesh implantation. Experimental changes in mesh stability].

The use of biomaterials for incisional hernia markedly reduces the recurrence rates. Disadvantages are high rates of local wound complications and restriction of mobility by the rigid "shell". The abdominal wall mobility after mesh implantation is analysed for eight different mesh materials. The initial textile testing reveals relevant differences in structure with marked asymmetry in the different directions. The materials are implanted as inlay in rats for 3, 7, 14, 21 and 90 days. The deformation of the abdominal wall following intraabdominal pressure of 0-70 mmHg (0-9.81 kPa) is documented by 3D-photogrammetry, the tensile strength by tearing of excised strips of mesh. Three commercial available materials and two laboratory modifications lead independently of their textile characteristics to a marked restriction of the rounded configuration of the abdominal wall. The tensile strength exceeds by far the physiologically necessary value of 16 N/cm. Three newly developed meshes made of multifilament polypropylene with reduced amounts of material (21% and 28% relative to Marlex) lead to no restriction of the abdominal wall configuration yet have uncompromised stability. It might be possible to reduce the rate of local wound complications by the use of these newly developed meshes.

Abdominal Muscles↗
PubMed1996

[Preperitoneal mesh-plasty in incisional hernia repair. A comparative retrospective study of 272 operated incisional hernias].

In a retrospective study on 245 patients we evaluated the results of 272 incisional hernia repairs in the Department Surgery of the University Hospital Aachen. The group consisted of 58% male and 42% female patients with a mean age of 61.1 years and 111 primary and 161 recurrent incisional hernias. Conventional techniques (simple closure, Mayo) and alloplastic repairs were performed in 69.9 and 30.1%, respectively. During the last 4 years we predominantly used the preperitoneal mesh repair with polypropylene mesh (Marlex). The results of 87% of our group of patients were evaluated by questionnaire and information from the family physicians (mean follow-up period 64 months). The patients who underwent preperitoneal mesh repair were examined clinically and with ultrasound. In comparison to the results of conventional hernia repair, early complications (seroma, hematoma) were higher. The recurrence rate, however, was significantly lower in this group with mesh repair (6.8%) than in patients without alloplastic augmentation (32.6%). Whereas preperitoneal mesh repair is convincingly the ideal surgical technique, optimization of the alloplastic materials by reduction of the amount of foreign substance and improvement of elasticity and biocompatibility is mandatory.

Adolescent↗
PubMed1996

[Pathophysiology of the abdominal wall].

The use of biomaterials for closure of incisional hernias requires meshes adjusted to the physiological forces. The intraabdominal pressure is mainly influenced by the activity of the transverse muscles. The abdominal fascia of corpses withstands forces of 60-80 N/cm in horizontal and 20-30 N/cm in vertical direction; tearing of sutures occurs below 30 N/cm in horizontal direction. Assuming the abdominal cavity to be a thin hollow sphere, the rupture forces are approximately 4-16 N/cm for a diameter of 8-3 cm. The meshes currently in use are much stronger than this, rupturing at 40-100 N/cm. The curvature of the abdominal surface can be measured by 3D-photogrammetry and is highly significantly reduced following mesh implantation (t-test, 2-sided, P < 0.01). Reduction of the mesh material can decrease the rate of local wound complications and the stiffness of the abdominal wall.

Abdominal Muscles↗
PubMed1994

[ID and Bio Vue systems--comparison of two systems for the typing of erythrocyte antibodies].

The gel centrifugation test ID Microtyping was compared with the column agglutination test BioVue for antibody (AB) screening by testing serum samples of 3,000 patients under controlled conditions: enzyme test (ET; Bromelin) and LISS indirect antiglobulin test (IAT), both incubated for 15 min at 37 degrees C. From a total of 64 ABs, more relevant or possibly relevant ABs were detected by ID than by the BioVue system (63 vs. 56). ABs only detected in ID were: anti-D 3, -Jk(a), E 1, -Le(b)1, -e 1, -C 1, -E,S 1. One anti-Le(b) was only detected by BioVue. The calculated sensitivity was 98.4% for ID and 87.5% for BioVue. Furthermore, this study showed a lower frequency of unspecific reactions or reactions due to irrelevant cold ABs in the ID system (ID: 2.3%, BioVue: 4.0%, specificity 97.7 vs. 96.2%).

ABO Blood-Group System↗
PubMed1993

[Septic shock and multiple organ failure in surgical intensive care. An animal experiment model on the analysis of pulmonary and intestinal dysfunction].

The study deals with an animal model for the problems of surgical intensive care patients. Following repeated applications of E. coli endotoxin WO 111:B4 under standard conditions, specific hemodynamic and biochemical (TNF, TXA2, PGI2, IL-6, PAF) and morphological (endothelium of the lung) alterations were detected. ARDS patterns induced by the sepsis were analyzed by high-frequency measurement of pressure and flow (385 measurements per breathing cycle). The role of the intestine in sepsis was investigated by ion-selective monitoring of surface potassium activity comparing mucosa and serosa. Every injection of endotoxin was followed by a selective increase of the potassium activity revealing relative ischemia induced by the endotoxin. The profile of the potassium levels on the surface correlates both with the cardiac output and with the prostacyclin levels. The continuous narrowing of the difference between mucosa and serosa, potassium during the period of investigation can be regarded as evidence for pathologic change in permeability fostering the septic course.

6-Ketoprostaglandin F1 alpha↗
PubMed1991

[Transfemoral extraction of a knotted Swan-Ganz catheter using an F24 dilator].

We report on the successful transfemoral extraction of a Swan-Ganz catheter twice knotted in a patient's heart. The extraction was performed with a Dormia basket and removed via a 24F dilatator which was placed in the femoral vein. The Swan-Ganz catheter had been placed in a 67-year old patient after Whipple's operation. The technical procedure of the catheter removal is described and the advantages are discussed.

Aged↗
PubMed1991

[Controlled study of cremaster resection in Shouldice repair of primary inguinal hernia].

237 Shouldice operations with resection of the cremaster muscle from the Department of Surgery of the RWT University of Aachen were compared with 153 Shouldice repairs without resection of the cremaster muscle from the Department of Surgery of the Elizabeth Hospital in Essen. The aim of this prospective controlled trial was to determine the value of the resection of the cremaster muscle in Shouldice's hernia repair. A comparable follow-up of 12 to 26 months in both groups revealed no significant differences in early-postoperative complications. In the group without resection of the cremaster muscle the incidence of chronic inguinal pain was reduced. However, avoidance of the cremaster resection is not advisable because it leads to atypical indirect recurrences and totally higher recurrence rate (2.6%), so four indirect recurrent hernias were diagnosed. In the group with resection of the cremaster muscle no indirect recurrent hernia was detected, only one direct recurrent hernia was documentated. The significantly elevated rate of recurrent hernias (p less than 0.05) and the occurrence of atypical indirect recurrent hernias in the group without resection of the cremaster muscle demonstrates the important influence on the technique of repair. Based on our results the resection of the cremaster muscle is an essential part of Shouldice's hernia repair.

Adult↗
PubMed1990

[Common channel syndrome--2 case reports].

The common channel syndrome is a disease mostly of young girls. To demonstrate the problems of diagnosis and therapy we report on 2 cases operated on in 1987 and 1989. The long delay of several years between the onset of symptoms and the diagnosis might be shortened by improved diagnostic possibilities (Ultrasound, ERCP). In any case of hyperamylasemia or chronic pancreatitis in childhood an obstruction of the biliary tract should be excluded. The common channel syndrome can be treated by means of sphincteroplasty or a bilidigestive anastomosis.

Amylases↗
PubMed1990

[Hypothermia and polytrauma. A case report (28 degrees C)].

In a 29-year-old polytraumatised motorbike driver, massive blood transfusion led to a decrease of the body temperature to 28.1 degrees C rectal on the second day after admission. We could rewarm the patient using only a Clinitron bed, although he had persisting blood loss due to an intravasal coagulopathy. This method has proven to be noninvasive, effective and without any side effects.

Adult↗