摘要:

An experimental multimicrobial gas gangrene rat model was developed and the therapeutic effect of surgery was compared to the combined effect of surgery and hyperbaric oxygen (HBO). The infection was caused by an intramuscular injection of a mixture of bacteria including Clostridium perfringens, Bacteroides fragilis, Escherichia coli and Streptococcus faecalis. The mortality, morbidity and wound healing were assessed during a follow-up of 2 weeks. The mortality of the control rats was 60%, with rats treated with surgery alone 35 % and the combined treatment group 20% (NS). In the combined treatment group, 84.4% of the survivors healed completely; the corresponding figure in the surgery group was 15.4% (p < 0.001). In experimental multimicrobial gas gangrene the addition of HBO to surgery reduces morbidity and improves wound healing but does not reduce mortality statistically significantly.

ISSN:0014-312X    

DOI:10.1159/000129288

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Twenty-nine patients, subjected to major abdominal surgery, were randomized to different types of postoperative fluid replacement, given on the basis of subcutaneous oxygen tension measurements (PscO2). One regimen consisted of crystalloids, the other of a combination of crystalloids and colloids (dextran 70). Perioperative fluid replacement was given according to clinical criteria and postoperatively according to polarographic PscO2 measurements. PscO2 was measured by a silicone catheter implanted in the upper arm. Two tubes of expanded polytetrafluoroethylene (ePTFE) were implanted next to the silicon catheter. They were removed on day 5 and 7, and analysed for hydroxyproline content. Total postoperative fluid support was equal in the two groups, and so was the hydroxyproline content on day 7. In conclusion, postoperative fluid substitution with dextran has no advantages over crystalloids only, with regard to granulation tissue formation if postoperative fluid support is optimum, according to PscO2 measurements.

ISSN:0014-312X    

DOI:10.1159/000129289

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The morphology of the healing process of microsurgical re-anastomosis of the rabbit oviduct with the use of fibrin adhesive, autologous and heterologous, and conventional sutures is described. Both oviducts in 48 rabbits were cut and reanastomoses were performed. The rabbits were killed at different intervals after the operations, ranging from 2 h to 28 days, and the anastomoses were evaluated by histomorphological examination.The autologous fibrin adhesive was absorbed after a week and an uncomplicated healing was observed. Heterologous fibrin adhesive caused a granulomatous inflammation interpreted as an immune reaction of the host to the foreign protein, and conventional suturing resulted in severe tissue damage with an intensive inflammatory reaction.

ISSN:0014-312X    

DOI:10.1159/000129290

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

This study was undertaken in order to assess the role of purely circulation-related effects upon free-radical-mediated reperfusion injury in the liver by comparing the respective effects of the oxygen free-radical scavenger superoxide dismutase (SOD) and the vasodilative action of papaverine in an ischemia/reperfusion model of the liver. Livers from male Wistar rats were rinsed blood free via the portal vein and stored ischemically (60 min at 37 °C in Krebs-Henseleit solution and 60 min at 4 °C in Euro-Collins solution). Reperfusion was carried out at a constant flow of 30 ml/min for 45 min at 37 °C in a nonrecirculating manner. Warm ischemic damage was evident in untreated livers compared to control livers, submitted solely to cold ischemia for 2 h at 4°C, by increased vascular resistance upon reperfusion, enhanced enzyme leakage from the parenchyme (glutamate pyruvate transaminase, glutamate dehydrogenase) and from the endothelium (purine-nucleoside phosphorylase), reduced tissue content of ATP and enhanced lipid peroxidation. Preischemic treatment with SOD or papaverine (the latter also given during reperfusion) significantly reduced hepatic vascular resistance and parenchymal enzyme loss in a comparable manner. Both drugs resulted in a significant increase of hepatic tissue content of ATP at the end of reperfusion. SOD, but not papaverine, prevented the leakage of purine-nucleoside phosphorylase and significantly reduced the tissue levels of lipid peroxides. Since induced vasodilatation by papaverine mimicked the beneficial effects of SOD on hepatocellular viability after reperfusion, we conclude that toxic oxygen species exert a major impact on the vascular system and that the hepatocyte is significantly altered by circulatory disturbances during reperfusion, which can be reduced by SOD as well as papaver

ISSN:0014-312X    

DOI:10.1159/000129291

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

A total of 112 orthotopic liver transplants with (AOLT) and without (NOLT) rearterialization were performed in 2 series using male Lewis rats as donors and recipients. In the first series, the 2-week survival rates were 5/11 (45.5%) in the NOLT group and 22/31 (71 %) in the AOLT group. The difference in survival was due to operative experience, as the NOLT transplants were performed before the AOLT transplants. In the second series, the NOLT (n = 30) and AOLT transplants (n = 40) were performed in random order. No differences in 2-week survival rates were found [NOLT, 29/30 (96.7%); AOLT, 37/40 (92.5%)]. Recovery of pre-operative body weight was, however, faster in the AOLT (7 days) than in the NOLT group (14 days). In the NOLT group, elevation of serum levels of GOT (p < 0.05 vs. AOLT at 3 days) and alkaline phosphatase (p < 0.01 vs. AOLT at 3 days and 1 week; p < 0.05 at 4 weeks) were found. We conclude from our results that in OLT without prolonged graft storage, survival is a sensitive marker of operative success only in the training phase. Once operative technique has been mastered, a success rate of greater than 90% should be achieved before inclusion of the animals in further scientific studies. As the AOLT animals recover body weight faster and have less evidence of liver injury up to 4 weeks post-transplantation, one is led to the conclusion that AOLT in the rat may be a better model for use in all liver transplantation research.

ISSN:0014-312X    

DOI:10.1159/000129292

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

This work was undertaken to investigate the role of nonparenchymal liver cells in a discordant model of hepatic xenografting. Three experimental groups were established: in group 1 guinea pig to Lew rat liver xenotrans-plantations were performed; in group 2 both donor and recipient were treated with dextran sulfate, a known inhibitor of the reticuloendothelial system phagocytic function; in group 3 both donor and recipient were injected with muramyl dipeptide, a synthetic immunomodulator stimulating the monocyte/macrophage axis. Survival time was assessed and xenoantibody titers 30 min before and after the intervention, Kupffer cell activity 30 min after transplantation, histology and immunoglobulin and complement deposits of the grafted liver were evaluated too. Survival time of the xenografted rats in group 1 was 6.4 ± 0.31 h. Blockade of Kupffer cells by dextran sulfate administration significantly (p < 0.001) depressed the survival time (2.9 ± 0.31 h) of the grafted rats, while a significant increase (p < 0.001) was observed in the muramyl dipeptide-treated group (9.3 ± 0.52 h). A significant reduction of xenoantibody titers 30 min after intervention was observed in the muramyl dipeptide group while no reduction was observed in the dextran group. Thirty minutes after xenotransplantation sheep red blood cell 51Cr uptake was significantly depressed by dextran sulfate treatment while muramyl dipeptide administration restored the Kupffer cell activity. Histological changes worsened after dextran administration in comparison with the other groups. Immunoglobulins and complement deposits were diminished by dextran administration. Our findings suggest that the increased ability of lining cells to clear preformed antibodies from the blood supply may be responsible, at least partially, for the prolonged survival observed in the muramyl-treated gro

ISSN:0014-312X    

DOI:10.1159/000129293

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

In a model of fully allogeneic heterotopic rat small bowel transplantation, the changes in intraepithelial lymphocyte (IEL) number and subpopulations were analysed. During early phases of rejection (5th postoperative day) a 4-fold increase in the number of IEL was observed when compared with native small bowel (4.05 vs. 15.84IEL/100 epithelial cells). When cyclosporine was given, counts were still as high as 11.4 and 12.58 on the 5th and 10th postoperative days, respectively. The percentage of CD8+ IEL, constituting a major population (84%) in the untreated small bowel, was significantly decreased (46.4%) during early phases of rejection. At that time, the majority of intraepithelial mononuclear cells were both CD8- and CD4-. In cyclosporine-treated animals, this was not observed until the 10th postoperative day. Some 23% of IEL in untreated animals expressed MHC class I antigens of the host; 17.2% (5th postoperative day) and 19.8% (10th postoperative day) did so in the cyclosporine-treated animals. Transmission electron microscopy revealed lymphocytes that bore cytoplasmic buds and pseudopods protruding between the enterocytes. There was no morphological difference between the IEL of rejected allografts and native small bowel. Due to the unspecific histologic changes associated with rejection, interpretation of histopathologic findings in mucosa biopsies of the allograft can be rather troublesome. An increase in the number of IEL is therefore a welcome additional marker of rejection.

ISSN:0014-312X    

DOI:10.1159/000129294

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

In order to study the activity of noradrenergic nerve fibres along mesenteric arteries in small-intestinal grafts, the entire jejunoileum was transplanted heterotopically in an isogeneic rat model (group I, n = 12). To assess their influence on graft motility, 9 cm of jejunum were transplanted in an orthotopic position and three bipolar electrodes sutured to the seromuscular layer of the graft (group II, n = 10). Fasting motility was recorded up to postoperative day 42. Animals of group I were sacrificed from day 7 on at weekly intervals and mesenteries were analysed histochemically by fluorescence microscopy. After the 1 st and 2nd week, grafts were found to be completely depleted of noradrenaline. At the end of the 3rd week, fluorescence became detectable along graft mesenteric arteries and showed normal intensity from the end of week 4. Migrating myoelectric complexes (MMCs) were present in all animals of group II. The variability of the MMC period (mean 12.6 min; SD 6.2 min) expressed as variation coefficient (median 36.5; 14.6–74) did not change during the observation period. From these findings it is concluded that there are no extrinsic noradrenergic activities in rat small-intestinal transplants for the first 3 postoperative weeks but they do recover there after. Their influence on graft function remains unclear: MMC periodicity, however, was no influence

ISSN:0014-312X    

DOI:10.1159/000129295

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

A canine model is described to study the tolerance of the pancreas to intra-operative radiotherapy (IORT). The canine pancreas is a horseshoe-shaped organ. To create a homogeneous delivery of IORT to the whole pancreas surgical manipulation is necessary which may induce pancreatitis. A resection of the left and right lobes of the pancreas facilitates the delivery of IORT, reduces the risk of pancreatitis and will demonstrate, eventually, minimal functional changes in the exocrine and endocrine pancreas at an earlier stage. Sixteen beagles were used. Investigations before and after the reduction procedure were intravenous glucose tolerance tests, serum insulin levels, faecal fat excretion, blood chemistry tests and body weight. Eight weeks after the pancreas reduction 15 dogs underwent an IORT procedure in which 25, 30 or 35 Gy IORT was delivered to the pancreatic remnant. We conclude that the pancreas reduction technique used to study the effects of IORT to the canine pancreas is feasible without mortality or morbidity. Endocrine and exocrine pancreatic function remained normal with a minimal follow-up of 3 months.

ISSN:0014-312X    

DOI:10.1159/000129296

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Intravenous prostacyclin (PGI2) is a potent pulmonary vasodilator in pulmonary hypertension. However, dose-dependent systemic vasodilation, an increase in intrapulmonary shunt and hypoxemia limit its clinical application. Recently, inhaled nitric oxide (NO) has been reported to elicit selective pulmonary vasodilation, but its clinical use is restricted by its potential toxicity; furthermore, the feasibility of NO application in clinical practice seems difficult. Therefore, we investigated the effects of PGI2 aerosol on pulmonary and systemic circulation and compared the hemodynamic effects to those of inhaled NO. In 6 dogs, ventilation with a hypoxic gas mixture (F102 0.09–0.11) increased pulmonary vascular resistance (PVR) by 196% (HPV). Aerosolization of a PGI2 solution at a concentration of 430 ng/ml reduced hypoxia-induced increase of pulmonary artery pressure by 48% and PVR by 52% within 6-10 min without systemic vasodilation. The administered dose of PGI2 was 0.87 ± 0.26 ng/kg/min. In 2 dogs, doubling the PGI2 concentration (860 ng/ml) did not enhance the vasodilatory effect. After termination of PGI2 inhalation, HPV was restored within 10–15 min. Inhaled NO (50 ppm) decreased the HPV-induced increase in PAP by 76% and in PVR by 73% within 5-10 min. Clinically relevant systemic vasodilation was not observed. It is concluded that inhalation of aerosolized PGI2 leads to selective pulmonary vasodilation in hypoxia-induced pulmonary hypertension. Aerosolized PGI2 at a concentration of 430 ng/ml was less potent than NO (50 ppm). However, due to the lack of known toxicity and its uncomplicated mode of application, inhaled PGI2 may be one alternative to inhaled NO in the treatment of acute pulmonary hyperten

ISSN:0014-312X    

DOI:10.1159/000129297

出版商:S. Karger AG    

年代:1993

数据来源: Karger