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1.
Microsurgery ; 20(3): 121-5, 2000.
Article in English | MEDLINE | ID: mdl-10790174

ABSTRACT

Microarterial grafts are prone to mechanical endothelial injury that can have profound effects on the transplanted vessel, a factor neglected in studies on vascular changes post-transplantation. The aim of this study was to document the integrity of the endothelial lining after both procurement and transplantation of rat aortic grafts, using a minimal touch technique with and without the use of topical papaverine. It was found that procurement using a simple minimal touch technique preserved the endothelium and transplantation could be performed without endothelial injury. The appearance of "normal" endothelium varied with the degree of distension of the artery, suggesting a dynamic endothelial architecture to accommodate changes in the surface area of the artery during pulsation. These findings indicate that transplantation of an arterial segment without injury to the intima is possible and stress the importance of technical controls after both procurement and transplantation to prevent the use of injured grafts and misleading results.


Subject(s)
Aorta, Abdominal/transplantation , Endothelium, Vascular/pathology , Tissue and Organ Harvesting , Animals , Microsurgery , Rats , Rats, Inbred Lew , Rats, Wistar
2.
Transplantation ; 67(1): 110-5, 1999 Jan 15.
Article in English | MEDLINE | ID: mdl-9921806

ABSTRACT

BACKGROUND: Acute rejection is still a major problem in renal transplantation and is one of the most important causes of chronic graft dysfunction and late graft loss. Selective immunosuppression with a humanized antibody against the alpha-chain of the interleukin (IL)-2 receptor (CD25) was evaluated to demonstrate the efficacy of this type of immunoprophylaxis in combination with dual immunosuppression. METHODS: We studied the effect of daclizumab, a humanized monoclonal antibody against the alpha-chain of the IL-2 receptor, in a randomized double-blind, prospective phase III clinical trial in 275 patients receiving a first cadaveric renal allograft. Among them 111 (83%) in the placebo arm and 116 (82%) in the daclizumab arm received the full regimen of five doses (1.0 mg/kg) every other week. Baseline immunosuppression consisted of cyclosporine and corticosteroids. RESULTS: At 6 months, 39 (28%) of the patients in the daclizumab group had biopsy-proven rejections, as compared with 63 (47%) in the placebo group (P=0.001). The need for additional antilymphocyte therapy, antithymocyte globulin, antilymphocyte globulin (ATG, ALG, OKT3) was also lower in the daclizumab group (8% vs. 16%, P=0.02), and they required significantly lower mean (+/- SD) cumulative doses of prednisone (3750+/-1981 mg vs. 4438+/-2667 mg in the placebo group, P=0.01). Graft function was significantly better (P=0.02) in the daclizumab group (graft function rate: 58 vs. 51 ml/min, mean) as was patient survival (P=0.01, 99% vs. 94%). No specific adverse events were observed in daclizumab-treated patients. Patients receiving daclizumab experienced fewer cytomegalovirus infections (18% vs. 25%), and none died from severe infectious complications, compared to four patients in the placebo arm. No patient in the daclizumab group had a lymphoproliferative disorder or any other form of immunosuppression-related tumor during the first year after transplant. CONCLUSIONS: Administration of daclizumab in addition to dual immunosuppression therapy significantly reduced biopsy-proven acute rejection after renal transplantation, improved patient survival, and did not add to the toxicity of the immunosuppressive regimen.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Graft Rejection/prevention & control , Immunoglobulin G/therapeutic use , Immunosuppressive Agents/therapeutic use , Kidney Transplantation , Adrenal Cortex Hormones/therapeutic use , Adult , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Humanized , Cadaver , Cyclosporine/therapeutic use , Daclizumab , Double-Blind Method , Drug Administration Schedule , Drug Therapy, Combination , Female , Humans , Immunoglobulin G/administration & dosage , Immunoglobulin G/adverse effects , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/adverse effects , Infections/chemically induced , Male , Middle Aged , Prospective Studies , Transplantation, Homologous
3.
Br J Urol ; 82(6): 877-81, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9883228

ABSTRACT

OBJECTIVE: To determine whether Dexon mesh, closely applied to the kidney, provides purchase for sutures to permit bladder/parenchymal apposition on autotransplantation and that, if this line of apposition were some distance from but surrounding renal papillae, urothelium would proliferate to cover exposed parenchyma to form a widely patent lumen; this should facilitate removal of the whole of an upper tract collecting system, retaining renal parenchyma alone. MATERIALS AND METHODS: To test this possibility and explore the practicability of the concept, nine dogs underwent bilateral nephrectomy followed by unilateral autotransplantation: the other kidney was discarded. Because the canine renal pelvis is intrarenal, the ureter was stretched maximally before passing fine scissors into the renal hilum to transect the collecting system as close to the kidney as possible in six of the nine dogs. In the remaining three dogs, partial nephrectomy was performed with division of the calyceal necks under vision. Thinned bladder wall was sutured to Dexon mesh some distance from the collecting tubules; omentum was applied to the suture line. RESULTS: Three dogs were killed prematurely at < 2 weeks because of perioperative complications. Four were killed at 2, 4, 5 and 8 weeks and two at 12 months. Dexon mesh proved to be an effective anchoring fabric, providing close apposition of bladder wall and parenchyma. There was no adhesion of the kidney to peritoneal contents. Urothelial proliferation to cover exposed parenchyma occurred early and by 12 months, a thin stroma was interposed between parenchyma and epithelium. The kidney was preserved in all but one removed electively, this dog having both cystitis and pyelonephritis at 12 months. CONCLUSIONS: This study showed that autotransplantation of a kidney after removal of its collecting system and advancement of thinned bladder wall to renal parenchyma is practicable, with regenerated urothelium bridging the deficiency by covering exposed parenchyma, to create a widely patent lumen.


Subject(s)
Kidney Transplantation/methods , Nephrectomy/methods , Polyglycolic Acid/therapeutic use , Surgical Mesh , Urinary Bladder/surgery , Animals , Dogs , Female , Suture Techniques , Transplantation, Autologous , Urologic Neoplasms/surgery
5.
J Invest Dermatol ; 108(5): 708-11, 1997 May.
Article in English | MEDLINE | ID: mdl-9129219

ABSTRACT

On the basis of previous studies that showed a negative association between HLA-A11 and skin cancer in renal transplant recipients and a positive association with HLA-B27 and HLA-DR7, we performed a study in Queensland with 1098 recipients to address the question of whether the same associations could be found. The influence of HLA mismatching and HLA homozygosity on the risk of skin cancer was also studied. In contrast to earlier studies, HLA-A11 was associated with an increased risk of skin cancer. On the other hand, we confirmed that the HLA-B27 antigen was associated with the development of skin cancer, but only when the development of basal cell carcinomas alone was considered, and we confirmed that there is a weak but not statistically significant association with HLA-DR7. No association between HLA mismatching or HLA homozygosity and the development of skin cancer was observed. Environmental factors such as different levels of exposure to sunlight and infection with human papillomaviruses are factors that are most likely to be involved. We hypothesize that human papillomavirus-induced antigens prevail in the skin cancers in the recipients living in the Netherlands, whereas antigens induced by solar radiation, the so-called "photo-antigens," may be more common in the skin cancers of the recipients living in Queensland. Exposure to sunlight can also induce immunologic unresponsiveness, and excessive exposure to sunlight in Australia may, therefore, simply override the risk factors that are important in countries with a more temperate climate.


Subject(s)
Carcinoma, Basal Cell/immunology , Carcinoma, Squamous Cell/immunology , HLA Antigens/analysis , Kidney Transplantation , Skin Neoplasms/immunology , Carcinoma, Basal Cell/epidemiology , Carcinoma, Squamous Cell/epidemiology , HLA Antigens/genetics , HLA-A Antigens/analysis , HLA-A11 Antigen , HLA-B27 Antigen/analysis , HLA-DR7 Antigen/analysis , Histocompatibility Testing , Homozygote , Humans , Kidney Transplantation/statistics & numerical data , Queensland/epidemiology , Risk Factors , Skin Neoplasms/epidemiology
6.
Pediatr Nephrol ; 10(2): 216-20, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8703718

ABSTRACT

Loin pain haematuria syndrome is a descriptive diagnosis of recurrent episodes of loin pain accompanied by haematuria, in which investigations do not reveal adequate pathology to account for the symptoms. The majority of patients present between 20 and 40 years, but onset may occur in older children. A significant number of patients show psychological and psychopathological features. Renal histology may show minor abnormalities, including mesangial proliferation, arteriolar and arterial hyalinosis and C3 in arterioles. Renal angiography is often normal but changes in intrarenal arterioles and cortical infarcts may be seen. Haematological abnormalities include decreased heparin-thrombin clotting time and elevated free plasma serotonin concentration. It is important that the assessment include a detailed psychiatric history, the patient's perception of pain, and the psychosocial environment. The pain may be very severe, leading to the requirement for addictive analgesics: management often becomes very difficult and frustrating to medical practitioners. Surgical intervention with capsulotomy, denervation and autotransplantation should only be considered as a last resort, as there is frequent recurrence of pain on the same or contralateral side.


Subject(s)
Hematuria/complications , Low Back Pain/complications , Adolescent , Adult , Diagnosis, Differential , Female , Hematuria/diagnosis , Hematuria/therapy , Humans , Low Back Pain/diagnosis , Low Back Pain/therapy , Male , Middle Aged , Syndrome , Treatment Outcome
7.
Transplantation ; 61(5): 715-21, 1996 Mar 15.
Article in English | MEDLINE | ID: mdl-8607173

ABSTRACT

A long-term retrospective follow-up study was performed to evaluate the risk of skin cancer in 1098 renal transplant recipients in Queensland, Australia. In a subgroup, we also assessed the influence of immunosuppressive therapy on the risk of developing skin cancer: cyclosporine alone or in combination with prednisolone; azathioprine alone or in combination with prednisolone; or the combination of cyclosporine and azathioprine with or without prednisolone. The cumulative incidence of developing skin cancer, calculated by life table analysis, increased progressively from 7% after 1 year of immunosuppression to 45% after 11 years and to 70% after 20 years of immunosuppression. Multivariate analysis in a subgroup comparing the risk of developing skin cancer in patients on either long-term cyclosporine or azathioprine (each with or without prednisolone) and in patients on the combination of cyclosporine and azathioprine (with or with- out prednisolone) showed no differences between the groups. We conclude that it is likely that the increased risk of skin cancer associated with immunosuppression is independent of the agent(s) used and is a result of the immunosuppression per se.


Subject(s)
Kidney Transplantation/adverse effects , Skin Neoplasms/etiology , Adolescent , Adult , Aged , Child , Child, Preschool , Cohort Studies , Female , Follow-Up Studies , Graft Rejection , Humans , Immunosuppression Therapy , Infant , Male , Melanoma/etiology , Middle Aged , Retrospective Studies , Risk
8.
Transplantation ; 59(3): 347-52, 1995 Feb 15.
Article in English | MEDLINE | ID: mdl-7871563

ABSTRACT

Between January 1, 1982, and November 1, 1986, 169 cadaver renal graft transplantations were performed at this hospital with CsA as induction therapy. OKT3 was not available in this period. Of these grafts, 15.9% were lost within 6 months, 10.7% from acute rejection (AR). Between November 1, 1986, and October 1, 1992, 483 cadaver renal graft transplantation were performed. Induction therapy included CsA and OKT3 was available. Of these grafts, 8.7% were lost inside 6 months, 3.1% from AR. Of these last 483 grafts, 113 received 125 courses of OKT3. Ten courses were prophylactic, and 115 courses in 103 patients were for rejection resistant to steroid therapy (biopsy proven in all but 2 cases. Ninety-three percent of rejection episodes treated with OKT3 responded, at least initially. Graft survival in OKT3-treated patients was 81%, 77%, and 76% at 6 months, 1 year, and 2 years, respectively. In contrast, graft survival in steroid-resistant rejection during the first period (without OKT3) was 59%, 57%, and 57% at these intervals. There were 8 infective deaths within 6 months in the 113 OKT3-treated patients, compared with 2 in the 343 who did not receive OKT3 (P < 0.001). There were 7 viral deaths in the OKT3 group compared with none in those not receiving OKT3 (P < 0.001). Prophylaxis with oral acyclovir and cotrimoxazole was instituted in October 1990 in OKT3-treated patients and ganciclovir use was increased. Since this change, no further viral deaths have occurred. OKT3 is a very effective antirejection agent, but its use is associated with an increased mortality from viral infections. With appropriate prophylaxis and treatment, however, this mortality can be reduced.


Subject(s)
Cyclosporine/administration & dosage , Graft Rejection/prevention & control , Kidney Transplantation/immunology , Muromonab-CD3/pharmacology , Drug Interactions , Drug Resistance , Follow-Up Studies , Humans , Kidney Transplantation/mortality , Steroids/therapeutic use
9.
Clin Transplant ; 9(1): 20-4, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7742578

ABSTRACT

Serial measurements of serum and urine markers of bone metabolism and of forearm bone density (BMD) by dual photon absorptiometry were performed in 22 patients undergoing renal transplantation in 1986. Patients were randomised to immunosuppression with (1) cyclosporin alone (CsA group, n = 10), (2) cyclosporin for 3 months followed by azathioprine-prednisone (CsA/AzP group, n = 3) or (3) long-term azathioprine-prednisone (LT AzP group, n = 9). As no reduction in bone mineral density (BMD) was noted in the first 6 months, groups 2 and 3 were considered together (AzP group, n = 12). Mean +/- SEM BMD fell by 19 +/- 2% at 36 months (n = 19, p < 0.01), with similar reductions seen in the CsA and AzP groups. At 60 months, BMD of the AzP group was 25 +/- 3% below baseline (p < 0.01), while the CsA group were only 5 +/- 4% below baseline (p = NS vs baseline, p < 0.05 vs AzP group). The degree of reduction in BMD over 5 years correlated with total glucocorticoid dose (r = 0.63, p < 0.05), but not with biochemical markers of bone turnover. Serum alkaline phosphatase fell post-transplant in patients treated with AzP, but not in the CsA group. These results demonstrate significant loss of forearm bone mineral with long-term follow-up after renal transplantation, but suggest that patients treated with cyclosporin monotherapy may be at lower risk of this complication.


Subject(s)
Bone Density , Immunosuppression Therapy , Immunosuppressive Agents/adverse effects , Kidney Transplantation/adverse effects , Absorptiometry, Photon , Adult , Alkaline Phosphatase/blood , Azathioprine/adverse effects , Azathioprine/therapeutic use , Bone Density/drug effects , Cyclosporine/adverse effects , Cyclosporine/therapeutic use , Female , Follow-Up Studies , Humans , Immunosuppressive Agents/therapeutic use , Kidney Transplantation/immunology , Male , Middle Aged , Prednisolone/adverse effects , Prednisolone/therapeutic use , Time Factors
10.
Aust N Z J Ophthalmol ; 22(1): 53-7, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8037915

ABSTRACT

One hundred and seventy-six patients who received a renal transplant between 1982 and 1988 were examined for ocular complications of steroid therapy. Posterior subcapsular cataracts (PSC) were present in 60 patients (34.1%). Patients were classified into three groups (HS, LS, NoS) depending on their maintenance immunosuppression therapy. The HS group received high doses of steroids after renal transplantation. LS had low steroid doses, and NoS had no steroids. The incidence of PSC was 21 of 38 in HS (55.3%), 33 of 117 in LS (28.2%), and 1 of 16 in NoS (6.2%). The difference between HS and LS was statistically significant (chi 2 = 8.1, P < 0.01). Grading the severity of PSC (PSC 0, PSC +, PSC > ++) showed a significant correlation between the degree of PSC and the steroid therapy. In the HS group, five patients had PSC +, and 16 had PSC > ++ (76%), compared to 19 patients with PSC +, 14 patients with PSC > ++ (42%) in the LS group (chi 2 = 4.6; P < 0.05). There was no correlation between the incidence of PSC and use of steroids for more than three months before dialysis. Comparison with the results of our earlier series (1973-1981) using high doses of steroids showed a similar incidence of PSC with HS (40.7% Series 1; 55.3% Series 2) but a lower incidence with LS and NoS.


Subject(s)
Cataract/chemically induced , Kidney Transplantation , Methylprednisolone/adverse effects , Prednisolone/administration & dosage , Adolescent , Adult , Aged , Child , Child, Preschool , Cornea/drug effects , Female , Graft Rejection/prevention & control , Humans , Immunosuppressive Agents/therapeutic use , Incidence , Intraocular Pressure/drug effects , Male , Methylprednisolone/administration & dosage , Middle Aged
11.
J Urol ; 150(5 Pt 1): 1375-9, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8411403

ABSTRACT

An extravesical ureteral implantation with the routine use of an internal stent was performed in 358 transplants (351 cadaveric and 7 living related). The 1-year patient and graft survival was 93% and 87%, respectively, with a minimum followup of 2 years. Ureteral complications developed in 9 patients (2.6%), with 3 fistulas, 2 of which resolved spontaneously, and 6 stenoses following stent removal. Nephrostomy drainage and antegrade stenting were initially attempted in all cases of stenosis, and were successful in 4. Revision of the ureteral anastomosis was required in 1 case of fistula and 2 cases of stenosis (0.9%). Extrinsic compression resulted in ureteral obstruction in 3 cases (2 lymphoceles and 1 hematoma), which resolved following drainage. Stent related complications occurred in 8 patients (2.2%), including obstruction due to the stent in 2 cases, breakage during removal in 3 leaving fragments in the upper urinary tract, proximal migration of 2 stents that were retrieved via percutaneous nephrostomy and calculus formation on 1 stent in a patient with hyperparathyroidism, necessitating extracorporeal shock wave lithotripsy for stent removal. In the cases with ureteral or stent related complications 1-year patient and graft survival was 100%. These results suggest that ureteral stents used routinely in renal transplantation are associated with a low incidence of urinary leaks, early postoperative obstruction and subsequent surgery for urological complications. However, a small number of unique problems related to stent use or malfunction may occur. Minimally invasive strategies using percutaneous nephrostomy and antegrade stenting are effective in managing the majority of complications that occur following ureteral stenting in renal transplant recipients.


Subject(s)
Kidney Transplantation/instrumentation , Stents/adverse effects , Equipment Failure , Follow-Up Studies , Graft Survival , Humans , Incidence , Kidney Transplantation/methods , Ureter , Ureteral Obstruction/epidemiology , Ureteral Obstruction/therapy , Urinary Tract Infections/epidemiology , Urinary Tract Infections/therapy
13.
Australas J Dermatol ; 34(2): 71-8, 1993.
Article in English | MEDLINE | ID: mdl-8311831

ABSTRACT

The 104 skin biopsies from 34 patients who attended a Renal Transplant Unit in Brisbane over 12 months included 40 squamous cell carcinoma (SCC), 22 solar keratoses, 4 hyperkeratoses, 18 warts and 11 basal cell carcinoma (BCC). Human papillomavirus (HPV) DNA was identified by Southern blot hybridisation using, as individual probes, purified insert DNA from recombinant HPV 1, 2, 3 or 3/10, 4, 5 or 5/8, 7, 11, 16, 18 and 41 under relaxed conditions and characterised by restriction enzyme analysis and Southern blot hybridisation under more stringent conditions. Genomic HPV DNA was characterised in 7 skin biopsies from 4 renal allograft recipients (RARs): HPV 1A in a SCC (20 copies/cell) and a BCC (10 copies/cell) from the one patient, HPV 36 (20 copies/cell) in a SCC, HPV 1A [symbol: see text] 1000 copies/cell) in a wart and HPV 2B (200-800 copies/cell) in 3 warts from the one patient. Only HPV 1A in the SCC exhibited a significant degree of subtype variation. HPV DNA was identified in another 5 skin biopsies from another 4 RARs: HPV 3A in a wart and a hyperkeratosis, HPV 3/10-related DNA in 2 solar keratoses and HPV 5/8-related DNA in another (20-50 copies/cell). The incidence of HPV 5 (or 5-related HPVs) in RAR SCC was very low and that of HPV DNA in RAR warts was lower than that recorded elsewhere but this was not due to insensitivity of the assays. There was no evidence for a role for HPV in the aetiology of skin cancer in RARs in south-eastern Queensland but the possibility remains that as yet unidentified HPV types are involved.


Subject(s)
DNA Probes, HPV , Kidney Transplantation , Papillomaviridae/isolation & purification , Skin/microbiology , Blotting, Southern , Female , Humans , Immunosuppression Therapy , Male , Middle Aged , Papillomaviridae/genetics , Skin Diseases/microbiology , Skin Neoplasms/microbiology
15.
Cryobiology ; 28(5): 413-21, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1752128

ABSTRACT

The necessary first step in successful organ cryopreservation will be the maintenance of endothelial cell integrity during perfusion of high concentrations of cryoprotective agents (CPAs). In this report we compare the effects of incubation on cultured porcine endothelial cells at 10 degrees C for 1 h with the CPAs glycerol, dimethyl sulfoxide (Me2SO), ethanediol (EG), and propane-1,2-diol (PG) in the vehicle solutions RPS-2 (high potassium, high glucose) and HP-5NP (low potassium, high sodium), both with and without added colloids. Tritiated adenine uptake and acid phosphatase estimation of cell number were used as indicators of cell viability. HP-5NP was superior to RPS-2 except with Me2SO when the differences in viability were not significant. Adding Haemaccel to HP-5NP improved the results, but adding albumin to RPS-2 was of no significant benefit. Osmotic stress appeared to be the major problem with glycerols use. Beyond 3.0 M the toxicity of Me2SO increased dramatically but it could not be determined if this was osmotic or chemical toxicity. PG was remarkably well tolerated to 3.0 M but a sharp decrease in cell viability beyond this concentration suggests that PG may be most useful with mixtures of other CPAs. Overall, EG appeared to be the least toxic CPA and in the context of vascular preservation warrants further investigation.


Subject(s)
Cryoprotective Agents/toxicity , Endothelium, Vascular/drug effects , Adenine/metabolism , Animals , Biological Transport, Active/drug effects , Cell Death/drug effects , Cells, Cultured , Dimethyl Sulfoxide/toxicity , Drug Evaluation, Preclinical , Endothelium, Vascular/cytology , Endothelium, Vascular/metabolism , Ethylene Glycols/toxicity , Glycerol/toxicity , Propylene Glycol , Propylene Glycols/toxicity , Solutions
16.
J Lipid Res ; 31(11): 1993-2000, 1990 Nov.
Article in English | MEDLINE | ID: mdl-2086698

ABSTRACT

Altered hepatic cholesterol metabolism has been implicated in the etiology of cholesterol gallstones. This hypothesis has been examined by determining acyl-coenzyme A:cholesterol acyltransferase (ACAT) activity in liver biopsies from 31 cholesterol gallstone patients and 12 control subjects. Hepatic ACAT activity in gallstone patients was decreased to one-third that in controls (P less than 0.001). No differences in hepatic homogenate or microsomal free and total cholesterol concentrations were observed between the two groups. However, marked increases in free (107%) and total (98%) cholesterol concentrations were found in the cytosolic fraction of liver biopsies from gallstone patients. The total phospholipid concentration of the liver homogenate fraction was unchanged in both groups; however, the microsomal total phospholipid concentration was reduced by 17% (P less than 0.01) in gallstone samples compared with controls. This difference did not result in a significantly increased microsomal cholesterol/phospholipid ratio for the gallstone group (0.180 +/- 0.030) compared with the control group (0.169 +/- 0.042). These results show that hepatic ACAT activity is significantly decreased in cholesterol gallstone patients. These changes in ACAT activity in livers of patients with cholesterol gallstones are consistent with the known increase in the amount of free cholesterol secreted in the bile of these patients. Thus, the changes in ACAT activity may contribute to the pathogenesis of cholesterol gallstones.


Subject(s)
Cholelithiasis/enzymology , Liver/enzymology , Sterol O-Acyltransferase/metabolism , Adult , Aged , Cholelithiasis/etiology , Cholesterol/metabolism , Female , Humans , Lipid Metabolism , Liver/metabolism , Male , Microsomes, Liver/enzymology , Middle Aged , Phospholipids/metabolism
17.
Clin Chim Acta ; 184(3): 259-68, 1989 Oct 16.
Article in English | MEDLINE | ID: mdl-2575465

ABSTRACT

The effect of ex vivo ischaemia at 37 degrees C on the activities of human hepatic acyl-CoA:cholesterol acyltransferase (ACAT), acyl-CoA hydrolase and carboxylesterase and on the microsomal cholesterol and total phospholipid concentrations was determined in liver tissue from two patients. ACAT activity decreased exponentially with ischaemia, corresponding to half-lives of 59 and 54 min in the two samples. Acyl-CoA hydrolase activity of microsomes was not affected by ischaemia, whereas carboxylesterase activity of microsomes decreased with a corresponding increase in cytosolic carboxylesterase activity. No changes in microsomal cholesterol and total phospholipid concentrations corresponding to the changes in ACAT or carboxylesterase activity were observed. ACAT activity was also determined in microsomes prepared from twenty human liver samples obtained at surgery with in vivo warm ischaemia times ranging from 5-120 min. The data obtained agree well with the ex vivo results, showing a half-life of 57 min for the loss of ACAT activity. Therefore, in comparing ACAT activities in liver samples with different ischaemia times, an appropriate correction must be made for warm ischaemia time.


Subject(s)
Ischemia/enzymology , Liver/enzymology , Sterol O-Acyltransferase/metabolism , Adult , Aged , Carboxylic Ester Hydrolases/metabolism , Cholesterol/metabolism , Female , Humans , Liver/blood supply , Male , Microsomes, Liver/enzymology , Middle Aged , Palmitoyl-CoA Hydrolase/metabolism , Phospholipids/metabolism
18.
Transplant Proc ; 21(1 Pt 2): 1389-90, 1989 Feb.
Article in English | MEDLINE | ID: mdl-2711441

ABSTRACT

This study identifies ultrastructural changes in the endothelium due to hypothermic HP-5 perfusion. These changes appear to be reversible and a manifestation of hypothermic hypoxia. This data provides a basis for improving perfusion techniques in both hypothermic preservation and cryoprotectant introduction and removal for cryopreservation.


Subject(s)
Endothelium, Vascular/ultrastructure , Mesenteric Arteries/ultrastructure , Tissue Preservation , Animals , Cold Temperature , Endothelium, Vascular/pathology , Male , Mesenteric Arteries/pathology , Rats , Rats, Inbred Strains , Reference Values
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