ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Rat, hamster, and rabbit islets were transplanted into diabetic C57BL/B6 mice. The effect on islet xenograft survival of low-temperature culture of the donor islets, αL3T4 treatment of the recipients for seven days, and transplantation of the grafts either in the renal capsule or in the liver via the portal vein was determined. Renal capsule transplants of control rat, hamster, and rabbit islets cultured at 37°C for one day produced normoglycemia in the recipients, with the mean survival time (MST) of the grafts ranging from 14 to 19 days. Low temperature culture alone did not produce a significant increase in the survival time. Treatment of the recipients with αL3T4 produced a marked prolongation of xenograft survival for all three species receiving renal subcapsular transplants of control or low temperature cultured islets. The range of MST* was from 34 to 46 days. The intrahepatic site produced an even further prolongation of the survival of concordant rat islet xen-ografts treated in this manner, with 60% of the recipients still normoglycemic at 100 days after transplantation. This enhancing effect of the intrahepatic site on survival did not occur with the discordant xenografts of hamster and rabbit islets.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The result of this study shows that a simple phosphate buffered sucrose solution (PBS) is better than hyperosmolar citrate (HOC) solution in the flush perfusion and hypothermic storage of canine kidneys for 72 hr prior to autotransplantation with immediate contralateral nephrectomy. The peroperative measurement of postre-perfusion renal blood flow revealed a significant reduction after 60 min in kidneys preserved with HOC solution. All grafts and animals in the PBS group (5/5) survived with primary renal function compared with one in the HOC group (1/5), which functioned after a period of oliguria. The early serum creatinine and urea levels were significantly lower in the PBS group, with a return to normal range within two weeks. This is reflected in higher inulin clearances and a more rapid recovery of proximal tubular function in the PBS animals, which also demonstrated a more rapid return of loop function and the ability to concentrate urine.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Depletion of CD4+T lymphocytes with monoclonal antibodies (mAbs) has been shown to prolong allograft survival in mice. In this study, two rat anti-CD4 mAbs, H129.19 and GK1.5, were administered either alone or in combination with cyclosporine (CsA) to recipients of MHC-mismatched (H-2kto H-2d) cultured fetal pancreas allografts to determine their effect on graft survival. When compared with control mice, splenic CD4+cells of GK1.5-treated mice were depleted by >95%, but in H129.19-treated mice no depletion of CD4+cells occurred. Instead, rat Ig was present on the surface of CD4+cells in H129.19-treated mice. Anti-CD4 therapy with either H129.19 or GK1.5 prolonged fetal pancreas allograft survival to a similar extent, but did not lead to indefinite survival. Blockade of the CD4 antigen by the mAb H129.19 was as effective as the depletion of CD4+cells by GK1.5 in prolonging allograft survival. Rejection of grafts by day 28 posttransplantation occurred in the absence of CD4+cells, as determined by both flow cytometric examination of spleen cells and immunoperoxidase staining of the graft site. CsA alone did not prolong graft survival, but its addition to either H129.19 or GK1.5 mAb treatment significantly increased the survival rate of grafts at 28 days compared with mAb treatment alone. These results suggest that CD4+cell depletion is not essential for effective anti-CD4 mAb therapy—and, further, that CsA may have a direct inhibitory effect on CD8+cells during allograft rejection.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

A 72-hr preservation of canine pancreas by a 2-layer (Euro-Collins'/Perfluorochemical) cold storage method was tested in the canine model of segmental pancreas autotransplantation. The functional recovery of the grafts by this method (group 1) was determined by daily fasting blood glucose concentration and intravenous glucose tolerance test at 2 weeks after autotransplantation and compared with simple cold storage with Euro-Collins' solution (group 2) and control (no preservation) (group 3).Maintenance of normoglycemia for at least 5 days after transplantation was considered a successful preservation. The functional success rates after 72-hr preservation were 100%, 0%, and 100% for groups 1, 2, and 3, respectively. The mean K values of group 1 after 72-hr preservation was 1.78±0.42 compared with 2.05± 0.32 for group 3 at 2 weeks after transplantation. Biopsies of grafts of group 2 after 72-hr preservation showed remarkable autolytic changes in exocrine and endocrine tissues. In contrast, biopsies of grafts of group 1 after 72-hr preservation showed almost normal architecture in both tissues. In addition, biopsies of 72-hr preserved grafts of group 1 at 4 weeks after after autotransplantation showed almost normal pancreas architecture with minimal fibrotic changes in the exocrine tissue. This study demonstrated the possibility of 72-hr preservation of the pancreas for transplantation.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

This study investigates whether phosphate metabolite concentrations and intracellular pH alter in early acute rejection of rat pancreatic allografts. In vitro biochemical assays, in vitro31P nuclear magnetic resonance spectroscopy, and in vivo31P NMR spectroscopy of the grafts were compared. Duct-ligated, vascularized rat pancreatic isografts and allografts were transplanted onto the infrarenal aorta of the recipients with inferior vena cava venous drainage. In order to obtain reproducible acute rejection, allografting was performed across a major histocompatibility barrier. For the in vitro experiments freeze-clamped graft extracts were prepared and analyzed for adenosine triphosphate concentration by fluorimetry, then placed in an 8.5 Tesla vertical bore magnet.31P NMR spectra were recorded using a Bruker AM 360 spectrometer operating at 145.7 MHz for31P. Spectra were acquired from nontransplanted controls; 3-day, 5-day, and 1-month posttransplant isografts, and 3-day and 5-day posttransplant allografts. All grafts examined were functioning satisfactorily. The ATP content of the extracts was significantly lower in the 3− and 5-day allografts than the respective isografts. Invasive in vivo31P NMR spectra were recorded using surface coils adjacent to the grafts from functioning 5-day posttransplant isografts and allografts (i.e., 3 days prior to an expected elevation in blood sugar from acute rejection in the allografts). The ATP/inorganic phosphate ratios and pH from the in vivo spectra were significantly lower in the allografts than in the isografts. It is concluded that changes in intracellular metabolism occur early in the process of acute rejection and that31P NMR spectroscopy may provide a means of diagnosing this before current methods.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

In order to compare saphenous bypass (SB) and percutaneous transluminal angioplasty (PTA) as treatment of renal graft artery stenosis (GAS), we have reviewed the results of both procedures in 33 patients treated consecutively by either SB (n = 16) or PTA (n = 17). All patients had become hypertensive within the first year after transplantation despite triple hypotensive drug therapy. SB was performed 17 (range 3–55) and PTA 19 (range 2–96) months after transplantation. SB failed in only 1 patient as a result of vascular thrombosis with graft loss. PTA was technically unsuccessful in 3 patients and was complicated by vascular branch thrombosis in 1 patient. Blood pressure decrease was similar in both groups: from 179/114 before SB to 147/90 (n = 15, P<.001) at 6 months and 150/93 (n=14,P<.005) at 12 months after SB and from 177/110 before PTA to 149/93 (n=13,P<.01) at 6 months and 150/95 (n=10,P <.02) at 12 months. At 1 year, control of BP was improved in 85% of SB group patients and 74% of PTA group patients. Recurrent stenosis was documented in 3 PTA group patients: subsequently 1 had a successful SB and the 2 others a repeated PTA—successful in 1, unsuccessful in the other.We conclude that both methods are equally effective for BP control but that PTA entails a higher rate of initial failure and a significant rate of restenosis. However, because of technical ease and better tolerance, PTA emerges as the first-choice treatment of GAS, SB remaining indicated when PTA is not feasible or has failed.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Although OKT3 monoclonal antibody is a useful therapy for refractory cardiac allograft rejection, the use of OKT3 for prophylaxis may be limited by the potential of sensitization and subsequent loss of efficacy on re-treatment. OKT3 was required for refractory rejection in 21 of 165 recipients transplanted between March 1985 and August 1988. Twelve of these patients had previously been exposed to OKT3, and the retreatment efficacy was evaluated. The study population averaged 42.1±15.3 years of age (mean ±SEM) and had experienced 2±1 previous episodes of rejection. The prior episodes of rejection had been treated with pulse methyl-prednisolone and antithymocyte globulin, and in addition 3 patients (25%) also required a course of antilymphoblast globulin. Retreatment OKT3 for refractory rejection was required 120±94 days following transplantation. CD3+lymphocytes were eliminated from the circulation within 24–48 hr in 11 of 12 patients, all of whom showed histologic improvement within the first week. Total resolution on the initial follow-up biopsy was noted in 9 (75%) during the course of therapy. Subsequent rejection episodes occurred in 9 (82%) of the survivors at 71±64 days. One-year survival was 83% in this vigorously rejecting patient population. Serious infections occurred within 3 months of therapy in 4 (36%). The side effects of OKT3 retreatment were similar to those seen with first exposure and did not require OKT3 discontinuation. Thus OKT3 may be administered with success in most patients who have previously been exposed to it.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Studies were made on the pathological lesions and biochemical indices of the livers of 22 patients in whom normal hemodynamics was maintained for 0–48 days after brain death by administration of vasopressin and epinephrine. Thirty-one specimens of liver tissues were obtained by percutaneous biopsy or at autopsy. The degrees of central venous congestion, central fibrosis, focal fibrosis, fatty metamorphosis, piecemeal necrosis, periportal fibrosis, and intrahepatic cholangitis in livers on various days after brain death were compared with those on the day of brain death (day 0). Central venous congestion was extensive on days 0–4, significantly less on days 5–14, and then again extensive on days 15–48. Central fibrosis and focal fibrosis showed no remarkable change during the 48-day period. Fatty metamorphosis, piecemeal necrosis, and periportal fibrosis showed no significant changes until day 16, but spread extensively on days 40–48. Intrahepatic cholangitis was scarcely observed on day 0 but began to increase after day 3, and spread extensively after day 5. The level of serum glutamic pyruvic transaminase did not increase in most patients until day 15. The mean value of prothrombin activity also did not decrease until day 15. However, the mean value of serum alkaline phosphatase increased gradually after day 3, and was correlated with cholangitis. The present study showed that during prolonged hemodynamic maintenance of brain-dead patients, pathological lesions did not spread or diminished and that biochemical indices did not become worse, or improved, in the first 2 weeks, except for increases in cholangitis and the serum alkaline phosphatase level.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Intraoperative blood requirements were analyzed in patients undergoing primary orthotopic liver transplantation and divided into two groups on the basis of panel reactive antibody of pretransplant serum measured by lymphocytotoxicity testing. One group of highly sensitized patients (n = 25) had PRA values of over 70% and the second group of patients (n = 26) had 0% PRA values and were considered nonsensitized. During the transplant procedure, the 70% PRA group received considerably greater quantities of blood products than the 0% PRA group—namely, red blood cells: 21.1±3.7 vs. 9.8± 0.8 units (P= 0.002), and platelets: 17.7±3.2 vs. 7.5± 1.5 units (P= 0.003). Similar differences were observed for fresh frozen plasma and cryoprecipitate. Despite the larger infusion of platelets, the blood platelet counts in the 70% PRA group were lower postoperatively than preoperatively. Twenty patients in the 70% PRA group received platelet transfusions, and their mean platelet count dropped from 95,050±l 1,537 preoperatively to 67,750±8,228 postoperatively (P= 0.028). In contrast, nearly identical preoperative (84,058±17,297) and postoperative (85,647±12,445) platelet counts were observed in the 17 0% PRA patients who were transfused intraoperatively with platelets. Prothrombin time, activated partial thromboplastin time, and fibrinogen levels showed no significant differences between both groups. These data demonstrate that lymphocytotoxic antibody screening of liver transplant candidates is useful in identifying patients with increased risk of bleeding problems and who will require large quantities of blood during the transplant operation.

ISSN:0041-1337    

出版商:OVID    

年代:1989

数据来源: OVID