摘要:

Increased vascular permeability to plasma proteins and altered hemodynamics at the site of inflammation are characteristics of inflammation. In the present study, alterations in endothelial barrier permeability were evaluated in different organs/tissues 6 h after a systemic injammatory response induced by intravenous infection of bradykinin (BK; 1.7 mg/kg). The effect of intravenous pretreatment with indomethacin or ibuprofen (cyclooxygenuse inhibitors), N-acetyl-L-cysteine (NAC, an oxygen free radical scavenger), and allopurinol (a xanthine oxidase inhibitor) was determined. Endothelial permeability was evaluated by determining tissue water content (TWC),125I-labeled human serum albumin (HSA) flux, and albumin leakage index (ALI) in various organs/tissues. The vasodilation in the local tissues was reflected by tissue blood content (TBC), measured by51Cr-labeled red blood cells. The results indicate that albumin flux signijcnntly increased in the peritoneum, pancreas, stomach, PSI, DSI, colon, kidneys, liver, lungs, and brain, TBC significantly increased in the kidneys, liver, lungs, and heart, as well as in the intestine, and an increased ALI, assaying endothelial permeability considering local hemodynamic alterations was noted in the pancreas, kidneys, liver, lungs, PSI, and DSI in the grozcp with BK alone. These changes were to varying degrees reversed by pretreaiment with indomethacin, ibuprofen, N-acetyl-L-cysteine, or allopurinol, where the protective effect tended to be organ-dependent.

ISSN:0894-1939    

DOI:10.3109/08941939609021275

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

Platelet-activating factor (PAF) is an important endogenous mediator of neonatal necrotizing enterocolitis (NEC). Injection of PAF into weanling and adult rats causes ischemic bowel necrosis that is morphologically similar to NEC. The purpose of this study was to adapt the PAF model of intestinal injury to the suckling rat and to attempt to alter susceptibility to PAF-induced bowel necrosis by early weaning and formula feeds. At ages 15 to 20 days, rat pups were selected to be weaned to either formula or 5% dextrose or to nurse ad lib (total n = 54). At ages 16, 18, 20, 21, 23, or 25 days of life, animals received PAF (50μg/kg) and endotoxin (I mg/kg) by intraperitoneal injection. Animals were sacrificed 2 h after injection. Intestinal samples were submitted to be graded by a pathologist in a blinded fashion. Injury scores ranged from 0 to 10, based on the percentage ofvillous necrosis. Prior to age 20 days, minimal histologic injury was present (mean scores on days 16. 18 = 1.7±0.9, 1.7±0.6). Combined injury scores for weaned and nursed animals on days 20 and 23 were significantly greater than on days 16 and 18 (p =. 0001). Histologic injury in the dextrose group was significantly less than the formula-fed group on day 21 and greater on day 25. Suckling rats showed resistance to PAF-induced bowel necrosis prior to 20 days of age, during the middle of the weaning period. Early weaning to formula did not alter susceptibility to injury, which suggests that PAF-acetylhydrolase from breast milk does not confer this resistance to PAF.

ISSN:0894-1939    

DOI:10.3109/08941939609021276

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

Chronic drainage of the thoracic duct to the esophagus was developed in dogs, and its efficacy in immunomodulation was tested using kidney transplantation. Compared to 9.7 days in the control, the mean animal survival was prolonged to 9.9 days, 17.8 days, and 18.5 days when TDD was applied preoperatively for 3 weeks, 6 weeks, and 9 weeks, respectively. Prolongation was significant after 6 weeks. Patency of the fistula was 93.5, 80.4, and 76.1% at respective weeks. Number of peripheral T-lymphocytes determined by a new monoclonal antibody diminished after 3 weeks. All animals were in normal health, requiring no special care for fluid, electrolyte, or protein replacement.

ISSN:0894-1939    

DOI:10.3109/08941939609021277

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

A study was conducted to determine the effect of sodium hydroxy ethyl starch (Hespan) on primary adhesion formation in a rabbit model. Hespan is a readily available volume expander. This was a randomized, double-blinded animal model in which New Zealand white rabbits were subjected to midline celiotomy. Adhesions were created by abrasion in both uterine horns, adjacent bowel, and peritoneum. Necropsies were performed at the 2-week interval and adhesions were graded. Significant decreases in type II and type III adhesions (p =. 032 and p =. 020, respectively) were demonstrated in Hespan-treated animals. Sodium hetastarch appears to decrease signifcant adhesion formation in treated animais and may have a roie as an adjunct for postsurgical prevention.

ISSN:0894-1939    

DOI:10.3109/08941939609021278

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

The univentricular heart complexes are a fairly common and potentially lethal set of congenital cardiac anomalies. Progress in developing new therapeutics has been hampered by a lack of suitable animal models. The authors developed a stable, closed heart preparation to systematically examine potential interventions. Using neonatal piglets (3.5–6.0 kg), a 6-mm PTFE graft was anastomosed end to end to the innominate artery and end to side to the pulmonary artery. An atrial septostomy was made, using a Rashkind septostomy catheter passed transsvenously. With the same catheter, the tricuspid valve was rendered incompetent. Occlusion of the right ventricular outflow tract completed a univentricular circuit. All cardiac output exited from the left ventricle, and pulmonary blood Jow was maintained via the innominate artery-to-pulmonary artery shunt. Pressure transducers measured central venous (mid inferior vena cava), aortic, and pulmonary arterial pressures. Oximetric probes recorded systemic venous and arterial oxygen saturations. Transit-time flow probes measured total cardiac output and pulmonary flows. Systemic flow was calculated by subtracting pulmonary flow from total cardiac output. This model has been completed in 30 animals. Minimal pressure drops have been recorded across the innominate-to-pulmonary artery graft. Pulmonary flows up to 700±52 mL/min were seen. Total cardiac outputs are as high as 1370±88 mL/min. Mean ratios of pulmonary to systemic flow (QI/Qsratio) range from 1.29±0.08 to 0.41±0.09. The model allows for full continuous monitoring of systemic and pulmonary pressures and flows and for accurate characterization of the physiological effects of respiratory and pharmacological interventions. In addition, mechanical constriction of the graft may allow direct alteration of the QI/QSratio, with determination of an optimum value for this ratio.

ISSN:0894-1939    

DOI:10.3109/08941939609021279

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

Adhesion formation is a major source of postoperative morbidity and mortality. Therefore, the reduction of postoperative adhesion formation would be of clinical benefit. Various modalities have been shown to reduce adhesion formation, including fibrinolytic enzymes, nonsteroidal anti-inflummatory drugs, and barriers that reduce the apposition of sites of potential adhesion formation. This study examined the ability of an inhibitor of thrombin, a recombinant hirudin analog (recHirudin), to reduce the formation of intraperitoneal adhesions in two rabbit models of adhesion formation. In the sidewall and double uterine horn models, recHirudin was administered via Alzet miniosmotic pump for the entire postoperative interval. In both of these models, there was a dose-dependent reduction in adhesion formation as measured by (1) the area of the sidewall injury that was involved in adhesions to the cecum and the bowel or (2) the involvement of the uterine horns to themselves or other peritoneal organs. These studies clearly demonstrate that postoperative administration of recHirudin to the site of injury reduced the formation of postoperative adhesions in two animal models.

ISSN:0894-1939    

DOI:10.3109/08941939609021280

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

The swine liver has been used for experimental transplantation and as an ex vivo support system for patients with fulminant hepatic failure. Preservation of liver function after the cold storage period can be accomplished by complying with several key steps during the procurement: Keep the procedure short, provide extensive exposure, allow only minimal dissection, irrigate the portal system through the splenic vein and thereby obtain regular blood flow through the organ up to the clamping point, and ice the liver abruptly in situ. This retrieval technique was used and evaluated in 10 pigs. The method allowed a short and successful organ procurement while preserving normal function of the liver ex vivo.

ISSN:0894-1939    

DOI:10.3109/08941939609021281

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

ISSN:0894-1939    

DOI:10.3109/08941939609021282

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor