ISSN:0894-1939    

DOI:10.3109/08941939609012476

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

Ramon Llull was a participant in a joint PhD program at the Department of Surgery, University of California, Irvine, California, USAIt has been shown that tolerance or specific immunologic nonresponsiveness in various lymphohemopoietic transplant models can be associated with the development of mixed Lymphoid chimerism. As a specific example, composite tissue (limb) allografts were studied as a model for vascularized bone marrow transplantation (VBMT) and it was demonstrated that development of stable cellular immune chimerism is associated with long-term allograft survival. Recently, studies were initiated using a new parental to hybrid VBMT model, but the detection of donor cells is complicated, due to the fact that they share one parental allotypic determinant, Therefore, regression analysis with a flow cytometric immunofluorescent staining assay was evaluated for the assessment of cellular lymphoid chimerism in donor parental to hybrid (P-F1) lymphohemopoietic transplant models. Standard curves consisting of known mixed populations of parental donor (Lewis, LEW) and hybrid host F1(Lew×BN, LBN) lymphocytes were established. Standard curves were analyzed by linear regression statistics and excellent coefficients of determination (r>.881) were obtained for all standard curves. A highly statistically significant (p<. 016) linear relationship between level of donor cell chimerism (independent variable) and percent stained (dependent variable) was determined. The technique was then evaluated using the parental to hybrid VBMT model. Levels of donor LEW lymphoid chimerism in all VBMT LBN recipients were successfully assessed by regression analysis and inverse prediction using distinct recipient allodeterminant markers. In conclusion, this technique was proven to be reliable and accurate for the detection of chimerism in parental to F1lymphohemopoietic allograft models.

ISSN:0894-1939    

DOI:10.3109/08941939609012477

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

To determine the effects of anti-inflammatory agents on hydrochloric acid lung injury, the heart and lungs were harvested from rats, placed in a lung chamber, constant flow perfused with whole blood, and ventilated. The following experiments were conducted: observation alone; intratracheal infection of normal saline; intratracheal hydrochloric acid; and intravenous meclofenamate or indomethacin before intratracheal hydrochloric acid. Wet-to-dry lung weights were measured. Peak airway pressures increased immediately (p<,001 vs. baseline; ANOVA) in all intratracheal groups, hydrochloric acid producing even greater (p<. 05) increases than saline—effects unaltered by meclofenarnare or indomethacin. The increased (p<. 001 vs. baseline) 2-h pulmonary artery pressures in hydrochloric acid-treated groups were unaltered by meclofenamate or indomethacin. All hydrochloric acid-treated groups demonstrated increases (p<. 05) in weight that were unchanged by meclofenamate or indomethacin. These data suggest that the beneficial effects of these medications described elsewhere, using a variety of in vivo lung injury experimental models, may be attributed to their experimental design, or to contributions from organshystems outside the pulmonary circuit.

ISSN:0894-1939    

DOI:10.3109/08941939609012478

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

These experiments were designed to determine the relationship between translocation of Escherichia coli and viability of ischemic small bowel. Twenty beagles were gavaged with14C-labeled E. coli at two time intervals (3 and 24 h) prior to ligation of the blood supply to a 40-cm segment of ileum. Mesenteric lymph node (MLN) biopsies and bacterial cultures of the peritoneal fluid, peripheral arterial blood, and splanchnic venous blood were taken immediately prior fo ligation and 24 h later both before and after the ischemic bowel was resected and anastomosed. Biopsies of each resection margin were taken to measure translocation of E. coli into the bowel wall. Several hemodynamic parameters were also measured before and 24 h after ligation. Seven of the 20 dogs died of further bowel necrosis. In survivors A-a DO2was significantly decreased 24 h after mesenteric ligation vs. preligation, whereas in dogs that died DO2was significantly increased after ligation vs. preligation. The incidence of mesenteric venous cultures positive for E. coli was significantly higher 24 h after ligation vs. preligation. However, there was no correlation between survival and the incidence of positive E. coli cultures in the blood or peritoneal fluid. Mean MLN counts were significantly higher in dogs gavaged at 3 h vs. those gavaged 24 h prior to laparotomy. However, there was no correlation between survival and translocation into either the bowel wall or MLN at either time interval. Viability of ischemic small bowel in this canine model was not affected by translocation of E. coli. Hemodynamic parameters that are altered during the course of sepsis also did not correlate with survival.

ISSN:0894-1939    

DOI:10.3109/08941939609012479

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

A transorbital approach to the pituitary gland is described in domestic swine weighing between 40 and 70 kg. A transpalpebral eye exenteration is performed and the optic canal is enlarged caudally, using a bone drill. An operating microscope is used to improve visualization of the surgical site as the pituitary stalk and anterior pituitary are exposed to the level of the optic chiasm. This approach exposes the pituitary sufficiently to perform either a hypophyseal stalk transection or a hypophysectomy or to implant cannulas for hypothalamic-hypophyseal portal blood sampling. This technique has been performed in more than 50 pigs without major complications. Postoperative recovery has been rapid and uneventful. The transorbital approach is a significant refinement of the frontal craniotomy and cerebral elevation technique previously described in the pig, and results in shortened surgery time, minimal brain manipulation, and greatly decreased morbidity.

ISSN:0894-1939    

DOI:10.3109/08941939609012480

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

Preliminary studies on ischemia/reperfusion injury in transplanted small bowel grafts showed that secretory phospholipase A2(sPLA2) may play a substantial role by breaking down membrane phospholipids. This study sought to determine the normal values of sPLA2in the rat small bowel as a function of site and length as a baseline for future studies. The entire small bowel of male Lewis rats (200 g) was flushed with normal saline to eliminate solid contents. In group 1, the entire small bowel was divided into 5-cm segments (numbered 1–9). which were snap frozen and processed the same day for sPLA2. In group 2, a 25-cm segment of bowel (corresponding to segments 2–6 in group 1) was harvested from each animal, snap frozen, and immediately processed for sPLA2. To assess the effect of bowel storage on enzyme content, group 3 and group 4 grafts were stored for 7 and 14 days, respectively, at -85°C prior to processing. All samples were homogenized in buffer, extracted with H2SO4, and assayed for sPLA2activity using [1–'4C]oleate-labeled autoclaved Escherichia coli as substrate. Results were analyzed statistically by ANOVA. sPLA2activity rose from 85.46±14.46% hydrolysis/min fraction-1in segment 1, to 476.38±176.75% hydrolysis/min fraction-1in segment 9. The increase was linear and statistically significant (p<.0001). There was no significant difference in enzymatic activity between groups 2, 3, and 4. Group 2 activity was 263.02±43.74% hydrolysis/min fraction-1. This value was not statistically different from the mathematically calculated mean of segments 2–6 in group 1 (237.75). The results show that (1) sPLA2activity increases predictably with distance from the ligament of Treitz, (2) storage at -85°C does not affect sPLA2activity, and (3) 25-cm grafts may be evaluated in toto with reproducible baseline enzyme activity. Given the variability of enzyme activity along the course of the rat small bowel, it is imperative that exact location be identified in any studies evaluating sPLA, activity.

ISSN:0894-1939    

DOI:10.3109/08941939609012481

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

Excessive flushing pressure in rat small bowel transplants may cause graft failure, but the optimal pressure for manual flushing has not been established. The goal of this study was to determine a safe yet effective pressure for intravascular graft flushing and to evaluate the consequences of higher pressures. The“usual”manual flush was found to be at a pressure of∼40 mm Hg. After harvest, grafts were flushed manually with heparinized normal saline solution while connected to a transducer. Two groups of 25-cin jejunal grafts (n = 5 each) were harvested from Lewis rats (200 g) on a pedicle of superior mesenteric artery and vein. Group 1 grafts underwent 3 successive flushes at 50, 100, 200 mm Hg, respectively. After each flush, full-thickness biopsies were obtained for light and transmission electron microscopy. Two grafts underwent syngeneic small bowel transplantation (SBTx), and biopsies were taken after reperfusion. Group 2 grafts were flushed at 50 mm Hg and biopsies were obtained. All grafts underwent SBTx and biopsies as in group 1. After flushing at 50 mm Hg, biopsies were essentially normal. When flushed at 100 mm Hg, there was pronounced epithelial separation with dilatation of the core of the villus. Flushing at 200 mm Hg resulted in complete separation of the villi, with occasional disruption in the crypts. All group 1 transplanted grafts were grossly nonviable immediately after reperfusion, while transplanted grafts in group 2 were grossly normal. The findings were consistent within each group and the difference between groups was statistically significant (0 vs. 100%). The results suggest that flushing pressures of 50 mm Hg in rat SBTx provide optimal evacuation of blood with minimal, reversible tissue injury. Higher pressures cause progressive histologic damage and may produce nonviable grafts. Flushing pressures in the rat model of SBTx should therefore be maintained at approximately 50 mm Hg.

ISSN:0894-1939    

DOI:10.3109/08941939609012482

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

The hemostatic properties of fibrin sealant have been well described. Previously published reports have attempted to clarify the possible role of fibrin glue in the inhibition of the formation of intrapericardial adhesions following cardiac surgery. Earlier work hypothesized that fibrin glue may reduce the severity of postoperative adhesions and that the use of autologous fibrin glue may have similar effects, without the risks that accompany homologous blood products. Six juvenile farm pigs were utilized to test this hypothesis. Conventional fibrin glue and single-donor fibrin glue were tested in open-heart surgery. This experimental model was also reexamined and found to be of significant utility in simulating adult reoperative cardiac surgery. The fibrin glue subjects were universally easier to reoperate due to fewer adhesions, as demonstrated grossly and histologically. The single-donor fibrin glue had no significant advantage on adhesion formation, when compared to the conventional fibrin glue group, but the ramifications of formulating fibrin glue in this fashion offer a significant benefit toward the complete use of autologous blood products in open-heart surgery.

ISSN:0894-1939    

DOI:10.3109/08941939609012483

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

ISSN:0894-1939    

DOI:10.3109/08941939609012484

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

ISSN:0894-1939    

DOI:10.3109/08941939609012474

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor