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71.
The many faces of multivisceral transplantation 总被引:8,自引:0,他引:8
T E Starzl S Todo A Tzakis M Alessiani A Casavilla K Abu-Elmagd J J Fung 《Surgery, gynecology & obstetrics》1991,172(5):335-344
The transplantation of multiple abdominal viscera, including liver-duodenum-pancreas, liver-stomach-duodenum-pancreas and liver-intestine, is being performed with increasing frequency and success. These procedures and other variations are derived from a seldom used multivisceral operation in which all of the foregoing organs are transplanted en bloc. It is described herein how the full multivisceral transplantation and its less extensive derivatives are based on the same principles of procurement, preservation and postoperative management. With all of these multiple organ permutations and with intestinal transplantation alone, management is complicated by inclusion in the grafts of a large lymphoreticular component that is capable of causing graft versus host disease (GVHD). Because of a systematic error in therapeutic philosophy, past efforts have been directed at altering or damaging the lymphoreticular cells by pretreatment of the donor or of the organs with drugs, irradiation or other means. From recent observations, the alternative approach is suggested of keeping these lymphoid depots intact, which then become the site of two way cell traffic after transplantation. With the use of powerful immunosuppression, such as that provided with FK 506, the donor lymphoreticular cells can circulate in the recipient without causing clinical GVHD, and the lymphoreticular cells in the graft become those of the recipient (local chimerism) without causing rejection. Even with avoidance of rejection and GVHD, metabolic interrelations between the grafted organs, and also between the graft organs and retained recipient viscera can affect the fate of the individual transplanted organs or retained recipient organs. The best delineated of these metabolic influences are mediated by the endogenous splanchnic hepatotrophic factors, of which insulin has been the most completely studied. An understanding of these various immunologic and nonimmunologic factors combined with more potent immunosuppression that is now available is sure to stimulate efforts at transplantation of abdominal organs and particularly of the hollow viscera that have resisted such clinical efforts. 相似文献
72.
S Lawless D Ellis A Thompson D R Cook C Esquivel T Starzl 《The Journal of pediatrics》1989,115(3):372-379
The aim of this study was to assess the hormonal alterations that may mediate the systemic hypertension that develops in patients during the perioperative period of orthotopic liver transplantation. We studied nine pediatric patients without previous hypertension or renal disease during six time points, starting before transplantation and ending at 48 hours after surgery. Hypertension developed in all patients in association with central venous pressures less than 10 mm Hg. Free water clearance was negative in all nine patients. Vasopressin levels increased intraoperatively but fell as hypertension developed. Atrial natriuretic factor levels increased as systemic blood pressure rose. A high level of plasma renin activity was observed in four patients with renal insufficiency. In six patients, postoperative 24-hour urinary norepinephrine excretion was within the normal age-adjusted range. These findings suggest that the combination of cyclosporine, corticosteroids, and, in some patients, an elevated plasma renin activity prevents the kidney from responding to the acute volume and salt overload with an appropriate diuresis and natriuresis, thus leading to systemic hypertension. The treatment of hypertension after liver transplantation may include salt restriction, diuretics, and, in those patients with a low creatinine excretion index, angiotensin coverting enzyme inhibitors. 相似文献
73.
B Koneru E Carone J J Malatack C O Esquivel T E Starzl 《American journal of diseases of children (1960)》1989,143(6):669-670
An isolated marked transient rise in serum alkaline phosphatase levels in otherwise healthy children is a well-documented occurrence. However, in children undergoing liver transplantation, elevated alkaline phosphatase values raise the possibility of biliary obstruction, rejection, or both. During a 6-year period, 6 of 278 children undergoing liver transplantation exhibited a similar phenomenon as an isolated abnormality. None had rejection, biliary obstruction, or other allograft dysfunction during a long follow-up. Eventually and without intervention, the alkaline phosphatase levels returned to normal. These instructive cases suggest that caution be used in advocating invasive procedures if elevated alkaline phosphatase levels are an isolated abnormality, and close observation with noninvasive testing is recommended. 相似文献
74.
BA DARLOW TE INDER KB SLUIS G NUTHALL N MOGRIDGE CC WINTERBOURN 《Journal of paediatrics and child health》1995,31(4):339-344
Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
75.
R D Gordon B W Shaw S Iwatsuki S Todo T E Starzl 《Surgery, gynecology & obstetrics》1985,160(5):474-476
A simplified technique for conversion of a complex hepatic arterial supply into a common channel is described. This technique permits single vessel anastomosis in the recipient of a liver transplant. 相似文献
76.
Low flow venovenous bypasses in small dogs and pediatric patients undergoing replacement of the liver 总被引:1,自引:0,他引:1
I Kam S Lynch S Todo A Dewolf F McSteen F Jakab B G Ericzon S Takaya T E Starzl 《Surgery, gynecology & obstetrics》1986,163(1):33-36
A venovenous bypass for transplantation of the liver was developed and evaluated in dogs and applied clinically, with flows that averaged less than 500 milliliters per minute. Fatal pulmonary emboli were seen in two of 40 experiments. The venovenous flow in the four pediatric recipients was 200 to 1,200 milliliters per minute, and there were no complications. 相似文献
77.
78.
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is an important
metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-
(3-pyridyl)-1-butanone (NNK). Using the chiral derivatizing agent, (R)-
(+)-alpha-methylbenzyl isocyanate [(R)-(+)-MBIC], previous work has shown
that the enantiomeric ratio of metabolically formed NNAL and its
glucuronide derivative may be species dependent. However, the absolute
configuration of such NNAL has not been previously reported. Synthetically
prepared racemic NNAL was converted to diastereomeric esters by reaction
with (R)-(+)- and (S)-(-)-alpha-methoxy-alpha-
(trifluoromethyl)phenylacetic acid (MTPA) chloride (Mosher's reagent) and
the products were characterized by 1H-NMR. Based on chemical shift data,
the absolute configuration of NNAL in each diastereomeric ester was
assigned. Hydrolysis of (R)-NNAL-(R)-MTPA gave (R)-NNAL. This was converted
to the corresponding carbamate by reaction with (R)-(+)-alpha- MBIC and the
absolute configurations of the diastereomeric carbamates formed by reaction
of (R)- and (S)-NNAL with (R)-(+)-MBIC were thereby assigned. Conversion of
metabolically produced NNAL to the same carbamates allowed us to assign the
NNAL formed from NNK by rat liver microsomes as (R)-NNAL. The major and
minor NNAL-glucuronide diastereomers found in the urine of patas monkeys
and humans exposed to NNK were similarly assigned; they were formed from
(R)-NNAL and (S)- NNAL, respectively.
相似文献
79.
Fifty seven children with thoracic empyema (37 boys and 20 girls) aged less than 12 years were seen at the University of Port Harcourt Teaching Hospital between January 1989 and December 1991. Staphylococcus aureus was the most common organism isolated from the pus of these patients (36 (63%) patients). Pseudomonas aeruginosa, the next most common organism, was isolated in 10 (18%) patients. The most common symptoms at presentation were acute illness with fever and cough (51 (89%) patients). All the patients were treated with closed intercostal tube drainage and appropriate antibiotics. Decortication was resorted to in only one patient. There were two deaths and the overall survival rate was 97%. 相似文献
80.