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J Heil

Publications and source records attributed to J Heil.

At least 37 records · Page 2Linked to original sources

En bloc simultaneous pancreas and kidney allotransplantation in the pig.

The pig is a large animal suitable for experimental pancreas transplantation due to its anatomy and transplant immunology, both of which are similar to humans. We established a model of en bloc simultaneous pancreas and kidney transplantation that decreases preservation time, operation time, and clamp time. The donor aorta--with celiac axis, superior mesenteric artery, and left renal artery--is anastomosed en bloc to the recipient's aorta in a side-to-oblique fashion. The portal vein is anastomosed end-to-side to the distal vena cava, and the left renal vein end-to-side to the left common iliac vein. The donor duodenum is anastomosed to the bladder to allow monitoring of the urinary amylase for rejection. En bloc transplantation is preferable for separating pancreas and kidney anastomoses in pigs. This technique could be used in humans, especially in adult uremic diabetic patients who receive a combined pancreas/kidney transplant from a pediatric cadaver donor.

Anastomosis, Surgical↗

Neuropsychological performance of young nondrinkers, social drinkers, and long- and short-term sober alcoholics.

Neuropsychological performance of 23-42-year-old males with diverse drinking histories was assessed. Comparisons were made among nondrinkers, social drinkers, short-term sober (less than 30 days) alcoholics and long-term sober (greater than 30 days) alcoholics. Results of these comparisons provided little support for the notion that neurotoxic effects of chronic alcohol consumption are directly related to cognitive impairment. Instead, these results suggested that performance differences among the groups were more closely related to subclinical withdrawal symptoms or native ability than to long-term alcohol consumption. Because none of the dependent measures was related to length of abstinence, and because Wechsler's Adult Intelligence Scale-R Vocabulary differences among groups paralleled neuropsychological test performance differences, it is suggested that differences among groups may reflect differences in native ability. In addition, there were no differences between social drinkers and nondrinkers, nor were there any significant correlations among drinking variables and performance of social drinkers, providing further evidence against a direct relationship between alcohol consumption and cognitive performance.

Adult↗

Experimental and clinical experience with urine amylase monitoring for early diagnosis of rejection in pancreas transplantation.

Pancreas allograft rejection in dogs with pancreaticocystostomy can be predicted in advance of hyperglycemia by monitoring the urinary amylase (UA) concentration (U/L): In initial experiments, UA values declined to less than 1000 1.3 +/- 0.2 days before hyperglycemia in nonimmunosuppressed dogs, 3.3 +/- 1.0 days in dogs treated with cyclosporine (CsA), and 9.3 +/- 0.7 days in dogs treated with CsA, azathioprine (Aza), and prednisone (triple therapy). Autotransplanted control dogs maintained high urine amylase concentrations indefinitely (mean 125,544 +/- 36,931). In a subsequent experiment, in 19 dogs with bladder-drained pancreas allografts on CsA only for prophylactic immunosuppression, a five-day course of antirejection treatment with Aza (5.0 mg/kg) and antilymphocyte globulin ALG (1 mg/kg) was started in group A (n = 10) when a raise in serum glucose was detected, and in group B (n = 9) when a drop of UA below 1000 was observed. The functional allograft survival rate was 9.2 +/- 0.5 days in group A (treatment started after hyperglycemia) and 29.0 +/- 5.7 days in group B (treatment started after drop in UA) (P = .002). The UA dropped in all dogs before hyperglycemia, at a mean of 2.7 days in group A and 20.8 days in group B. Clinically, 8 patients received a whole cadaver pancreas transplant with urinary drainage of the exocrine secretions. All were followed with UA monitoring. Three recipients lost the grafts for technical reasons. Three recipients lost the grafts for technical reasons. One had a primary non-function and UA was below 1000 U/24 hr; two developed abscesses and the grafts were removed while functioning with high UA values. Five grafts are currently functioning; 3 recipients had no rejection episodes and their UA values ranged from 30,000 to 100,000 U/24 hr during their entire postoperative course. The other two had rejection episodes. In both cases UA decreased to baseline levels 1 and 4 days in advance of the hyperglycemia. After antirejection treatment UA rose again to high values and plasma glucose levels declined. Both patients are currently insulin-independent, with UA values ranging from 10,000 to 200,000 U/24 hr. Both experimentally and clinically UA is an early predictor of pancreas allograft rejection. The institution of early treatment of rejection episodes in dogs, based on UA, significantly improved allograft survival. Urine amylase monitoring in pancreas transplant recipients could lead to an early treatment of rejection and improve graft survival.

Amylases↗

Definition of normothermic ischemia limits for kidney and pancreas grafts.

Normothermic ischemia tolerance is an important aspect of organ procurement and transplantation. The function of pancreas and kidney autografts was investigated in totally pancreatectomized or nephrectomized canine recipients. In 30 dogs the left limb (tail) of the pancreas was removed but left in the abdominal cavity after cessation of blood flow to produce warm ischemia for 30, 60, and 120 min (10 dogs at each time point), and then was flushed with cold Ringers' lactate and transplanted to the iliac vessels. Twenty dogs with fresh pancreatic transplants were controls. The success rate of pancreas transplants with warm ischemia of 1/2 and 1 hr was the same as that of controls (80%); however, after 1 hr normothermia 5/10 dogs had episodes of hyperglycemia for 1 week before glucose levels came back to normal. All but one graft with 2 hr warm ischemia failed. Intravenous glucose tolerance test (IVGTT) mean (+/- SEM) K values were not different in the successful groups, i.e., no warm ischemia: -1.55 +/- 0.15%; 1/2 hr warm ischemia: -1.81 +/- 0.18%; 1 hr warm ischemia: -1.64 +/- 0.09%. Amylase levels increased after transplant with maximum values at Day 2, then returned to normal, but the levels remained elevated in recipients of grafts subjected to longer normothermia with evidence of pancreatitis after 1 hr warm ischemia. Fifteen kidney grafts were treated similarly with warm ischemia exposure of 1/2 hr (n = 9) and 1 hr (n = 6) before being flushed and autotransplanted, and were compared to 16 fresh kidney transplants. After 1/2 hr warm ischemia none of the kidney grafts failed but 78% of the recipients had elevated serum creatinine and urea nitrogen levels which returned slowly to normal after 3 to 4 weeks. There was only one long-term survivor after 1 hr warm ischemia. Thus the pancreas seems to be more resistant to warm ischemia damage than is the kidney. This difference should be taken into consideration in regard to organ procurement for clinical transplantation.

Amylases↗

Urinary amylase monitoring for early diagnosis of pancreas allograft rejection in dogs.

The diagnosis of pancreas allograft rejection is usually made on the basis of blood glucose concentration, a late indicator of rejection. We performed segmental pancreas transplants in totally pancreatectomized dogs with the exocrine secretions drained into the bladder (ductocystostomy). We directly measured exocrine pancreatic secretions (urinary amylase), in an attempt to find a sensitive indicator for early rejection. Five groups were studied: (I) autografts; (II) autografts immunosuppressed with cyclosporine (CsA), azathioprine and prednisone; (III) allografts without immunosuppression; (IV) allografts immunosuppressed with CsA alone; (V) allografts immunosuppressed with CsA, azathioprine, and prednisone. The control groups (I, II) maintained high urine amylase concentrations indefinitely (mean +/- SE of 125,544 +/- 36,931 u/liter). Rejection, as diagnosed by rise of serum glucose to greater than 150 mg/dl, occurred at a mean (+/- SE) of 9.0 +/- 0.2 days in nonimmunosuppressed recipients of Group III, at 9.3 +/- 0.7 days in cyclosporine-treated dogs of Group IV, and at 28.0 +/- 8.3 days after transplantation in dogs immunosuppressed with triple therapy of Group V. In all allograft recipients, urine amylase declined precipitously (less than 1000 u/liter) before the onset of hyperglycemia, by 1.3 +/- 0.2 days in Group III, 3.3 +/- 1.0 days in Group IV, and 9.4 +/- 2.8 days in Group V. In a further experiment, nine dogs with pancreas allografts received cyclosporine for prophylactic immunosuppression; further antirejection therapy with azathioprine and antilymphocyte globulin was given for 5 days beginning the first day that rejection was diagnosed. In five dogs (Group A) rejection was diagnosed when serum glucose rose to greater than 150 mg/dl.(ABSTRACT TRUNCATED AT 250 WORDS)

Amylases↗

Effects of lesions in the paraventricular nucleus of the hypothalamus on vasopressin and oxytocin contents in brainstem and spinal cord of rat.

The effects of lesions of the paraventricular nucleus in rat hypothalamus (PVN) on the vasopressin (AVP) and oxytocin (OT) contents of the brainstem and spinal cord, as measured by radioimmunoassay, were studied. AVP decreased by 50% and 80% in brainstem and spinal cord of lesioned animals, whereas OT disappeared almost completely. Therefore, in contrast to OT, the PVN is not the only site of origin of AVP-containing nerve fibers projecting to the brainstem.

Animals↗

Preservation of canine segmental pancreatic autografts: cold storage versus pulsatile machine perfusion.

The reliability of cold storage and pulsatile machine perfusion for preservation of open-duct segmental pancreatic grafts for 24, 48, and 72 hours was determined in a canine autograft model. The tail (left limb) of the pancreas on a pedicle of splenic artery and vein was transplanted to the pelvis with vascular anastomoses to the iliac vessels and the remainder of the pancreas was excised. Twenty nonpreserved grafts functioned immediately (the recipients became normoglycemic, plasma glucose less than 150 mg/dl), 16 long term (80%). Collins solution (CS, osmolality 300 mosm/kg) and a silica gel filtered plasma solution (SGF-I, osmolality 430 mosm/kg) were compared for cold storage at 4 degrees C. The long-term functional survival rate for grafts stored for 24 hours in SGF-I was 9/12 (75%) and in CS was 8/12 (67%). When graft preservation time was extended to 48 hours, 9/12 (75%) stored in SGF-I and 4/10 (40%) in CS functional long term. The preservation failure rates were 0% in grafts stored in SGF for up to 48 hours, but were 20% and 50% for grafts stored in CS for 24 and 48 hours. Storage at 72 hours was not satisfactory; even when SGF-I was used, the preservation failure rate was 57%. SGF was also used as the perfusate for pancreas preservation on the Mox-100 machine at a pressure of 30 mm Hg (achieved by leaving the port opposite the connected pancreas open). Lower pressures gave insufficient perfusion and higher pressures led to severe edema of grafts. Mean (+/- S.E.) flow (ml/min) through the grafts were 4.5 +/- 0.3 initially, 6.5 +/- 0.7 at 24 hours and 6.3 +/- 0.9 at 48 hours. With SGF-I only 6/12 (50%) of grafts perfused for 24 hours and only 1/8 (12%) for 48 hours functioned long term. With a modified perfusate (SGF-II, osmolality 470-500 mosm/kg) the results were slightly improved; 7/12 (58%) grafts perfused for 24 hours and 5/10 (50%) for 48 hours functioned long term. The mean (+/- S.E.) flow rate (ml/min) was 5.0 +/- 0.6 in grafts that functioned long term and was 8.3 +/- 1.0 in those that failed due to preservation complications. Mean (+/- S.E.) peak serum amylase levels (I.U./L.) were similar in recipients of fresh grafts (3953 +/- 365) and those stored hypothermically in SGF (4226 +/- 327), but were significantly lower in recipients of machine perfused grafts (2988 +/- 228). Although the percentage of successful transplants varied according to the preservation techniques, the mean (+/- S.E.) IVGTT K-values in recipients with functioning grafts were similar between the groups (-1.44 +/- .19 to -1.82 +/- .17%). The pure pancreas preservation failure rates with machine perfusion were between 30% and 40% at 24 to 48 hours, compared to 0% in those simply stored in cold SGF for 24 to 48 hours. We conclude that pancreas preservation by cold storage in high osmolar silica gel filtered plasma is more reliable than pulsatile machine perfusion and provides sufficient time to complete the logistical maneuvers necessary for clinical pancreas transplantation from cadaver donors.

Animals↗