| 1. |
- Berndsen, FH, et al.
(författare)
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Does mesh implantation affect the spermatic cord structures after inguinal hernia surgery? An experimental study in rats
- 2004
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Ingår i: European Surgical Research. - : S. Karger AG. - 0014-312X .- 1421-9921. ; 36:5, s. 318-322
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Tidskriftsartikel (refereegranskat)abstract
- Background: Inguinal hernia repair is the most common operation in general surgery. Prosthetic reinforcement of the inguinal area with polypropylene mesh has increased dramatically in the last decade. The aim of this study was to evaluate how different types of mesh affect the spermatic cord structures. Methods: Thirty rats were divided into three groups. The spermatic cord was dissected free and a conventional suture repair was performed in group I, an operation mimicking the Lichtenstein operation with a heavyweight polypropylene mesh in group II and the same operation using large pore, lightweighted polypropylene/polyglactin composite mesh in group III. A vasography was performed after 90 days. The cross-sectional area of the vas deferens and s-testosterone from the spermatic vein were measured using the contralateral side as control. Light microscopy of the inguinal canal was performed and inflammation and fibrosis were graded. Results: Vasography revealed patent vas deferens in all animals. In group III, there was a lower s-testosterone in the spermatic vein and a reduced cross-sectional area of the vas deferens on the operated compared to the control side. However, there was no difference in the other groups and there was no significant difference in s-testosterone levels between the groups. There was significantly more inflammation and fibrosis after mesh repair compared to suture repair, but there was no difference between the two mesh groups. Unexpectedly, polyglactin fibres were still seen in specimens in group III after 90 days. Conclusion: In conclusion, the only effect on the spermatic cord structures in a rat model is seen as an impaired s-testosterone production and a reduced cross-sectional area of the vas deferens after use of a low-weight composite mesh compared to the control side. No difference in inflammation or fibrosis was found between heavyweight polypropylene mesh and low-weight composite mesh. Copyright (C) 2004 S. Karger AG, Basel.
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| 2. |
- Hjalmarsson, Claes, et al.
(författare)
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Intravenously Administered Human Epidermal Growth Factor in the Rat. Biliary Excretion and Influences on Pancreatic Secretion.
- 2003
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Ingår i: European Surgical Research. - : S. Karger AG. - 0014-312X .- 1421-9921. ; 35:2, s. 81-85
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Tidskriftsartikel (refereegranskat)abstract
- <i>Background/Aim:</i> Epidermal growth factor (EGF) is known to exert mitogenic effects in different tissues, including the digestive tract and pancreas. EGF is also found in high concentrations in pancreas. Infusion of human EGF has been shown to induce proliferation of cells in exocrine pancreas, and to increase the thickness of the small intestine. The aim of this study was to investigate the influence of intravenously administered human EGF on pancreatic and biliary secretions in the rat. <i>Materials and Methods:</i> Rats were fasted overnight and were given human EGF intravenously, either as a bolus dose of 5 µg or as a continuous infusion in increasing doses from 0.5 to 10 µg/h. Bile and pancreatic juice were either collected together or separately. The concentration of human EGF in bile and pancreatic juice was measured. <i>Results:</i> After a bolus dose of EGF increased bile/pancreatic secretion was seen after 60 and 90 min when the bile and pancreatic secretions were not separated. Continuous infusion of EGF increased the joint secretion rate of bile and pancreatic juice in a dose-dependent manner. No effect on secretion rate was seen when bile and pancreatic juice were collected separately. After intravenous infusion of human EGF a 1,000-fold increase of human EGF excretion was found in bile but not in pancreatic juice. <i>Conclusion:</i> Intravenously administered human EGF was excreted in high concentrations in bile and increased the secretion rate of pancreatic juice when collected together with bile. The results suggest that EGF, at least partly, exerts its effect on the pancreas and the proximal gastrointestinal tract after excretion with bile and stimulates pancreatic secretion via this route.
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| 3. |
- Liu, Qing, et al.
(författare)
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Linomide and antibody-targeted superantigen therapy abolishes formation of liver metastases in mice.
- 2003
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Ingår i: European Surgical Research. - : S. Karger AG. - 0014-312X .- 1421-9921. ; 35:6, s. 457-463
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Tidskriftsartikel (refereegranskat)abstract
- Hematogenous spread of tumor cells and metastasis formation in the liver are insidious aspects of cancer progression and are not frequently amenable to curative treatment. We examined the effect of Linomide and antibody-targeted therapy against the formation of hepatic metastases in vivo. For this purpose, syngenic B16 melanoma cells transfected with GA733-2 (a human colon cancer cell surface antigen) were injected into a mesenteric vein of C57/Bl6 mice. To test bacterial superantigen (Sag) targeting for immunotherapy of liver metastases, we used genetically fused proteins consisting of SEA and a Fab moiety of a GA733-2 tumor-reactive antibody (C215Fab-SEA). Linomide dose-dependently reduced hepatic metastases, and at 300 mg/kg this reduction was more than 80%. Treatment with C215Fab-SEA decreased metastases formation by 49% and the combination of Linomide and C215Fab-SEA was found to completely abolish liver metastases (>99% reduction). Taken together, our novel data suggest that Linomide and antibody-targeted superantigen therapy individually markedly reduce and together abolish liver metastases. Considering that current therapy of hepatic metastases is mainly limited to surgical resection in a subgroup of patients, these findings indicate that Linomide alone or in combination with antibody-targeted superantigen may provide a novel approach against liver metastases.
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| 4. |
- Ljungdahl, M, et al.
(författare)
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Intramucosal pH and pCO(2) do not strictly correlate with intestinal energy metabolism in experimental peritonitis.
- 2000
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Ingår i: European Surgical Research. - : S. Karger AG. - 0014-312X .- 1421-9921. ; 32:3, s. 182-90
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to investigate tissue hypoxia on the cellular level in sepsis. Eighteen pigs weighing 18-27 kg were studied. Intramucosal-arterial PCO(2) gradient (PCO(2)-gap) and intramucosal pH (pH(i)) were calculated using tonometry. A blind loop of the small intestine was constructed for repeated tissue biopsies to measure intestinal energy-related metabolites and lactate concentration. Six animals served as controls. In 12 animals, faecal peritonitis was induced. Six of these animals were studied without further interventions, while the others were resuscitated with dextran to maintain cardiac index at baseline level. Untreated peritonitis caused an increase in PCO(2)-gap and a drop in pH(i). The intestinal energy metabolism was not disturbed until the end of the experimental period, with a decreased energy charge value and a moderately increased lactate concentration. In peritonitis-dextran animals, PCO(2)-gap and pH(i) remained at baseline level and the energy metabolism was not disturbed. We conclude that in peritonitis, PCO(2)-gap - like pH(i) - can be influenced by other factors than strictly anaerobic tissue metabolism.
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| 5. |
- Lundberg, G, et al.
(författare)
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A rat model for severe limb ischemia at rest
- 2003
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Ingår i: European surgical research. Europaische chirurgische Forschung. Recherches chirurgicales europeennes. - : S. Karger AG. - 0014-312X. ; 35:5, s. 430-438
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Tidskriftsartikel (refereegranskat)abstract
- We sought an animal model able to discriminate metabolic and angiogenic processes in limb ischemia. For that we modified and evaluated a rat model of severe unilateral limb ischemia at rest. A two-stage surgical procedure entailing left femoral artery ligation preceded by interruption of collateral vessels originating from the infra-renal aorta and left iliac arteries was performed in Sprague-Dawley rats. The model was evaluated for up to 8 weeks with a transit-time flow meter, a laser Doppler perfusion imager, microspheres, arteriography and histology. It was found to be well tolerated with low mortality and perfusion in the foot skin was reduced up to 8 weeks, while collaterals were visible after 2 weeks. Histologic signs of ischemia were seen for up to 4 weeks. This rat model of severe limb ischemia at rest lasts up to 8 weeks and seems well suited for longitudinal studies of the pathophysiology of limb ischemia and healing mechanisms like angio- and arteriogenesis.
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| 6. |
- Nilsson, C., et al.
(författare)
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Effect of selective denervation of the rat pancreas on pancreatic endocrine function
- 2001
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Ingår i: European Surgical Research. - : S. Karger AG. - 0014-312X .- 1421-9921. ; 33:2, s. 86-91
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate the influence of selective denervation of the rat pancreas on hormone secretion and on peripheral insulin sensitivity. Thirteen rats, 7 denervated and 6 sham operated, received an intravenous glucose challenge for 30 min. The basal plasma levels of insulin, glucagon and glucose did not differ between the two groups. An augmented insulin response to glucose was detected in the denervated group, whereas the glucagon response was unaffected. Glucose tolerance was marginally improved. Twenty-four rats, 12 denervated and 12 sham operated, received a constant infusion of glucose, insulin, epinephrine and propranolol in order to inhibit the endogenous insulin release and thus evaluate insulin sensitivity. No significant change in insulin sensitivity could be detected during our experimental conditions. We conclude that selective denervation brings about an increased insulin response to glucose, probably by interrupting a catecholaminergic negative tone on the beta -cell. The sympathectomized animals did not disclose any apparent changes in peripheral insulin sensitivity.
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| 7. |
- Thorlacius, Henrik, et al.
(författare)
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Isolated liver perfusion permits administration of high doses of chemotherapeutic agents. Comparison with hepatic artery infusion
- 2001
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Ingår i: European Surgical Research. - : S. Karger AG. - 0014-312X .- 1421-9921. ; 33:5-6, s. 342-347
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Tidskriftsartikel (refereegranskat)abstract
- Tumor cells are dependent on glutamine metabolism and acivicin, which is a selective glutamine antagonist, has been shown to effectively retard tumor growth in several malignancies. However, systemic treatment with acivicin is associated with significant side effects. The purpose of the present study was to examine whether use of an in vivo isolated liver perfusion model may allow administration of lethal doses of acivicin and compare it to regional infusion of acivicin in the hepatic artery. Five days after tumor inoculation, acivicin was administered by an isolated liver perfusion model or by regional infusion via the hepatic artery. It was found that regional infusion of acivicin (5 and 10 mg/kg) via the hepatic artery caused systemic illness and diarrhea, and all animals in this group died within 3 days. In contrast, we observed no signs of systemic illness, diarrhea or hepatocellular injury in rats receiving isolated liver perfusion with or without acivicin (10 mg/kg) administration. Noteworthy, we found that isolated perfusion with acivicin reduced the glutamine content in liver tumors by 39% compared to perfusion with control medium. In line with this, it was found that isolated perfusion with acivicin (10 mg/kg) inhibited tumor growth in the liver. Taken together, this study suggests that application of the isolated liver perfusion model avoids the toxic and lethal effects of high doses of chemotherapy, herein acivicin, and may provide a useful approach to treat liver tumors in vivo.
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| 8. |
- Torkvist, L, et al.
(författare)
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Role of CD18-dependent neutrophil recruitment in skin and intestinal wound healing
- 2001
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Ingår i: European surgical research. Europaische chirurgische Forschung. Recherches chirurgicales europeennes. - : S. Karger AG. - 0014-312X. ; 33:4, s. 249-254
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Tidskriftsartikel (refereegranskat)abstract
- CD11/CD18 is an important adhesion molecule mediating recruitment of leukocytes, which, in turn, may cause postoperative injury in the skin and gastrointestinal tract. The objective of the present study was to investigate the effects of inhibiting the function of CD18 on surgery-induced dermal and intestinal infiltration of neutrophils and on the healing of surgical skin flaps and colonic anastomosis. A flap in the dorsal skin or an end-to-end colonic anastomosis were created in Sprague-Dawley rats. Skin necrosis and anastomotic breaking strength were analyzed 6 and 3 days after surgery, respectively. Tissue myeloperoxidase (MPO) was used as a marker of neutrophil recruitment. Administration of a monoclonal antibody directed against rat CD18 (WT.3, 2 mg/kg) significantly decreased dermal and anastomotic MPO activity by more than 80%. Passive immunization against CD18 significantly improved flap survival, i.e. the survival was 80% in the anti-CD18 antibody group as compared to 38% in the control group. In contrast, this passive immunization against CD18 had no effect on the reconstitution of the integrity of the colonic anastomosis, i.e. the anastomotic breaking strength was 1.3 ± 0.1 and 1.3 ± 0.3 N in the control and anti-CD18 antibody group, respectively. These findings suggest that specific inhibition of CD18 function and reduced neutrophil recruitment may improve the survival of experimental skin flaps and, thus, may represent a potential target for therapeutic intervention. In contrast, we also found that blocking CD18-dependent neutrophil infiltration in the intestine had no effect on breaking strength of colonic anastomosis. Thus, neutrophils may influence the wound-healing process differently in specific organs and this needs to be considered when applying an anti-inflammatory treatment regime in order to improve tissue healing.
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