摘要:

The hemodynamic benefits and pulmonary vascular selectivity of amrinone, dobutamine and amrinone + dobutamine were assessed in a canine model of vasoconstrictive pulmonary hypertension. Dogs were equipped with central and peripheral catheters and with an electromagnetic flow probe placed around the ascending aorta for the measurement of cardiac function. Through a laparotomy, an arteriovenous fistula was created between the abdominal aorta and the inferior vena cava. Gradual opening of this fistula, which permitted construction of pressure-flow curves (mean pulmonary artery pressure over the cardiac index, PAP/CI), was utilized to identify the pulmonary vascular effects of amrinone and dobutamine. PGF2α, prostaglandin derivative, induced stable pulmonary hypertension along with significant reduction in CI. The resultant pulmonary hypertension translated into a significant increase in both the slope and pressure intercept of the PAP/CI curve. The bipyridine derivative, amrinone, did not reverse the CI reduction observed with PGF2α: both mean arterial pressure and PAP were decreased as was the intercept of the PAP/ CI curve. Dobutamine, a β-agonist, reversed the CI decline elicited by PGF2α but the elevated pulmonary pressure remained unaffected; dobutamine reduced the slope of the PAP/CI curve. When combined, amrinone and dobutamine demonstrated additive beneficial hemodynamic effects and improved lung perfusion. Their additive effects were also indicated by data on the PAP/CI curve: both the slope and the pressure intercept were significantly reduced. These results suggest that amrinone and dobutamine interact at different sites of the pulmonary vasculature and that their association might be beneficial in vasoconstrictive pulmonary hypertension although no significant pulmonary vascular selectivity could be obser

ISSN:0014-312X    

DOI:10.1159/000129337

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

In a prospective randomized clinical study a routinely used bubble oxygenator (Bentley-5TM) was compared with a hollow fiber membrane oxygenator (D 701 Masterflo 34) during hyperthermic isolated extremity perfusion. This was done to find out whether there were differences between the two oxygenators in hemolysis, cellular damage, oxygenation and temperature achieved during extremity perfusion. In 30 perfusions blood samples were obtained at defined times: plasma hemoglobin (Hb), serum lactate dehydrogenase (s-LDH), number of erythrocytes, mean corpuscular volume (MCV), hemoglobin and bilirubin were determined for hemolysis, leukocyte count (neutrophils, lymphocytes, monocytes) and platelets as a check for cellular damage, and PO2, PCO2, O2 saturation and pH to define blood oxygenation and CO2 elimination. Maximal increase in temperature after 30 min and perfusion time until maximum tissue temperature were also recorded. The membrane oxygenator yielded better results from the aspect of hemolysis: s-LDH and plasma Hb were significantly different (p < 0.001). Cellular damage was less with the membrane oxygenator: platelet differences were significant (p < 0.01). Oxygenation and hyperthermia were obtained more quickly and were better controllable in membrane oxygenator. Further advantages for the patient were the smaller volume of blood needed for priming in a membrane oxygenator (750 vs. 1,200 ml) and improved safety resulting from a ‘closed’ perfusion system. On the basis of the clinical prospective randomized trial conducted, we conclude that membrane oxygenators must be adopted as the new standard in isolated hyperthermic extremity perfus

ISSN:0014-312X    

DOI:10.1159/000129338

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Dynamic changes in liver plasma membrane fluidity caused by regeneration and atrophy were assessed in rats following portal branch ligation (PBL). The portal branch, which perfuses 70% of the liver, was ligated with 5-0 prolene, and liver plasma membranes were isolated by ultracentrifugation. The membrane fluorescence polarization was measured as an index of membrane fluidity using 1,6-diphenyl-1,3,5-hexatriene (DPH) as the probe dye. In nonligated lobes, a significant decrease in fluorescence polarization was observed 12 and 24 h after PBL (0.171 ± 0.004, p < 0.01 and 0.165 ± 0.005, p < 0.001, respectively) as compared to the controls (0.181 ± 0.002). The fluorescence polarization values then gradually returned to near control levels. In contrast, in the ligated lobes, the fluorescence polarization had increased by 12 hours after PBL (0.196 ± 0.002, p < 0.01), and remained significantly elevated (p < 0.01) for up to 1 week after PBL, gradually returning to control levels within 3 weeks. The membrane composition was also evaluated by analyzing the cholesterol/ phospholipid (C/P) ratio. A significant increase in the C/P ratio was detected in the ligated lobes 12 h and 3 days after PBL, but there was no significant difference in fluorescence polarization values between nonligated lobes and controls. These results suggest that alterations in membrane fluidity play an important role in the regenerative and atrophic processes of the liver following portal branch ligat

ISSN:0014-312X    

DOI:10.1159/000129339

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Expression of neural cell adhesion molecule (NCAM) in the digestive system was studied with NE-150 monoclonal antibody, together with those against Lewis blood group antigens. NE-150 did not react with any of 32 cell lines tested derived from digestive tract cancers. In gastric adenocarcinomas NCAM was not expressed regardless of its differentiation status, while in gastric carcinoids and in other carcinoid tumors of different organs, it was present in all the specimens tested. Among normal tissues, it reacted with the deep gastric gland and the islets of Langerhans. These results suggest that NCAM is one of the most specific markers for gastric carcinoid tumors. It was also suggested that the gastric carcinoid tumor might be derived from NCAM-positive cells in the deep gastric gland. These findings should be exploitable in subgrouping gastric tumors in terms of antigen expression.

ISSN:0014-312X    

DOI:10.1159/000129340

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Standardized intra-abdominal hemorrhage was induced in 7 anesthetized pigs. The resulting hypovolemic shock was treated with pneumatic anti-shock garment (PASG) followed by intra-aortic balloon occlusion. The effects of this treatment on circulation, lung mechanics and gas exchange were studied. Hemorrhage was induced by pulling out sutures introduced in the inferior caval vein. We found that the use of PASG partially restored mean arterial blood pressure from 44 ± 6 to 66 ± 6 mm Hg. When intra-aortic balloon occlusion was added, the arterial pressure returned to basal levels. Cardiac output fell severely due to the hemorrhage from 3.7 ± 0.2 to 1.3 ± 0.2 liters/min and could not be restored during the treatment. A severe fall in total lung compliance was recorded after inflation of the PASG from 18.6 ± 0.9 to 10 ± 0.7 ml/cm H2O, this was accompanied by a fall in alveolar ventilation. These findings emphasize the severe restriction in lung function that occurred during treatment with PASG. Both parameters returned to near normal values when the PASG was deflated and the intra-aortic balloon was inflated. Pulmonary vascular resistance increased by more than 400% and remained high during the study period. There was no change in arterial PO2, however the fall in mixed venous PO2, caused by hemorrhage was reversed at the end of the treatment. Indirect monitoring of cerebral function by continuous EEG showed a decreased voltage during the hemorrhage, this was reversed by the combined treatment. We conclude that the outlined treatment makes it possible to restore central hemodynamics and preserve cerebral function at least for a short period of time until definite surgical treatment can be performed. However, severe restriction on lung mechanics, especially when PASG was inflated, makes it probable that ventilatory support can be necessary in such

ISSN:0014-312X    

DOI:10.1159/000129341

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Postoperative formation of adhesions is a common complication in abdominal surgery. The aim of the present study was to develop standardized experimental models for quantitative studies of the formation of adhesions in rats and rabbits. In rats the suturing of a peritoneal wound increased adhesion formation significantly compared to leaving it open, 77.9 ± 4.8 and 5.3 ± 2.8%, respectively (p 0.05). Different types of trauma resulted in differences in adhesion formation to noninjured parts in the abdominal cavity, adhesions in 17.5 and 2.5% of the animals, respectively (p < 0.05). In rabbits adhesions formed more frequently (p < 0.001) to visceral peritoneum (59.3 ± 3.7%) than to the parietal one (22.3 ± 1.6%) indicating a different propensity of tissues to have adhesions. These models enable detailed quantitative studies on experimental formation of adhe

ISSN:0014-312X    

DOI:10.1159/000129342

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

To examine the difference in hepatic ketogenesis during the regeneration process between cirrhotic and normal liver, arterial ketone bodies (acetoacetate and 3-hydroxybutyrate), free fatty acids and glucose concentrations and liver regeneration rate were determined at 0, 1, 2, 3 and 7 days after partial (70%) hepatectomy in thioacetamide-treated cirrhotic and normal rats. Hepatic ketone body production per unit liver was calculated by total ketone body concentration × blood volume/the remaining liver weight. The regeneration of cirrhotic liver was delayed compared with that of normal liver. In normal rats, total ketone body concentration increased on the 1st day both after hepatectomy and sham operation, and returned to the basal level thereafter. In cirrhotic rats after hepatectomy or sham operation, however, total ketone body concentration did not increase throughout the experimental period although free fatty acids level increased more greatly than in normal rats. Arterial ketone body ratio (acetoacetate/3-hydroxybutyrate) and glucose level decreased on the 1st day after hepatectomy, and recovered after the 2nd day in both cirrhotic and normal rats. Hepatic ketone body production after hepatectomy was significantly greater in normal rats than cirrhotic rats, and hepatectomy itself increased hepatic ketone body production in both rats on the 1st and 2nd postoperative days. In conclusion, hepatic ketone body production is impaired after hepatectomy in cirrhotic rats, which is possibly related to the delayed regeneration of cirrhotic liver

ISSN:0014-312X    

DOI:10.1159/000129343

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0014-312X    

DOI:10.1159/000129344

出版商:S. Karger AG    

年代:1994

数据来源: Karger