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R S Sung

Publications and source records attributed to R S Sung.

17 recordsLinked to original sources
PubMed2006

Kidney and pancreas transplantation in the United States, 1995-2004.

This article examines OPTN/SRTR data on kidney and pancreas transplantation for 2004 and the previous decade, and discusses recent changes in kidney-pancreas (KP) allocation policy and emerging issues in kidney donation after cardiac death (DCD). Although the number of kidney donors continues to increase, new waiting list registrations again outpaced the number of kidney transplants performed, rising by 11% between 2003 and 2004 and contributing to a 1-year increase of 8% in the number of patients active on the waiting list. DCD has increased steadily since 2000; 39% more DCD transplants were performed in 2004 than 2003. Both deceased donor and living donor kidney graft survival rates remain excellent and are improving. The number of people living with a functioning kidney transplant doubled between 1995 and 2004, to 101,440 with a functioning kidney-alone and 7213 with a functioning KP. Health care providers in all settings are more likely to be exposed to these transplant recipients. Patient survival following simultaneous pancreas-kidney (SPK) transplantation is excellent and has improved incrementally since 1995; death rates in the first year fell from 60 per 1000 patient-years at risk in 2001 to 45 in 2003. The number of solitary pancreas transplants increased dramatically in 2004.

Adolescent↗
PubMed2005

Preliminary analysis of early outcomes of a prospective, randomized trial of complete steroid avoidance in liver transplantation.

Steroids are a mainstay in liver transplantation for induction and maintenance immunosuppression but are associated with significant adverse effects. While prior studies have successfully limited the use of steroids, whether complete steroid avoidance will improve outcomes remains unclear. To further evaluate the need for steroids, consenting patients who underwent liver transplantation between June 2002 and May 2004 were entered into a prospective, randomized trial to receive either standard therapy (tacrolimus, mycophenolate mofetil, steroid induction/maintenance) or complete steroid avoidance (standard therapy without steroid induction/maintenance). Clinically suspected rejection was confirmed by biopsy and treated with pulse steroid therapy. Outcomes were compared on an intention to treat basis. Of the 72 patients enrolled, 36 (50%) were randomized to the steroid avoidance group with a mean follow up of 412 +/- 41 days. Donor and recipient characteristics were similar between groups. The steroid avoidance group was more likely to have significant infections (52% vs 28%, P = .03). There was a trend toward an increased rate of acute rejection (25% vs 14%, P = .23). Twelve of 36 recipients (33%) enrolled in the steroid avoidance group later received steroids. The incidence of recurrent hepatitis C was similar between groups. The 1-year patient (90% vs 83%, P = .44) and graft survivals (90% vs 81%, P = .27) were similar between groups. These data suggest complete steroid avoidance in liver transplantation results in acceptable patient and graft survival. However, the potential long-term benefits of steroid avoidance, including a decrease in severity of recurrent hepatitis C, remain under investigation.

Adrenal Cortex Hormones↗
PubMed2001

Excess risk of renal allograft loss associated with cigarette smoking.

BACKGROUND: Cigarette smoking contributes to a number of health-related problems, but its impact on renal transplant survival beyond accelerated patient death is unclear. METHODS: We performed a cohort study of 645 adult renal allograft recipients from 1985 to 1995 to evaluate the relationship between smoking and graft outcome. RESULTS: Twenty-four percent of recipients (156/645) were smokers at the time of transplant evaluation. Of these, 90% continued to smoke after transplantation. Pretransplant smoking was significantly associated with reduced overall graft and death-censored graft survival. Patients who were smokers at the time of pretransplant evaluation had kidney graft survival of 84%, 65%, and 48% at 1, 5, and 10 years, respectively, compared with graft survival in nonsmokers of 88%, 78%, and 62% (P=0.007). Pretransplant smoking adversely affected death-censored graft survival in recipients of cadaveric (P=0.02) and of living donor kidneys (P=0.02). Reduced graft survival in pretransplant smokers could not be accounted for by differences in rejection (64% vs. 61%, P=0.35). In a multivariate analysis, pretransplant smoking was associated with a relative risk of 2.3 for graft loss. Among patients with a smoking history before transplantation, death-censored graft survival was significantly higher for those who quit smoking before transplant evaluation. CONCLUSIONS: Cigarette smoking before kidney transplantation contributes significantly to allograft loss. The effect of smoking on graft outcome is not explained by increases in rejection or patient death. Smoking cessation before renal transplantation has beneficial effects on graft survival. These effects should be emphasized to patients with end-stage renal disease who are considering renal transplantation.

Adult↗
PubMed2001

TNFalpha and IFNgamma induced by innate anti-adenoviral immune responses inhibit adenovirus-mediated transgene expression.

The transient nature of adenovirus-mediated transgene expression has been attributed to adaptive immune responses to adenoviral proteins and transgene products. However, the cytokines interferon-gamma (IFNgamma) and tumor necrosis factor-alpha (TNFalpha) inhibit transgene expression from adenoviral vectors in vitro by a transcription-related mechanism, and their early induction following vector administration in vivo suggests a contribution of innate immunity in regulating transgene expression. In this study, the significance of cytokine expression and its relation to adaptive and innate immunities were determined in TNFalpha-knockout mice, IFNgamma-knockout mice, or anti-IFNgamma mAb-injected animals. Adenoviral LacZ reporter expression directed by human cytomegalovirus (HCMV) promoters was greater in magnitude and duration than that by the murine CMV (MCMV) promoter. beta-Galactosidase reporter gene expression up to day 7 was greater in cytokine-deficient animals compared with wild type. Decrements in transgene expression occurred in advance of adaptive immune responses and were not due to alterations in specific adaptive immunity or vector clearance in cytokine-depleted mice. We conclude that TNFalpha and IFNgamma inhibit early adenovirus-mediated transgene expression by HCMV and MCMV promoters in vivo. Cytokine inhibition of expression is independent of adaptive immunity and is likely secondary to innate immune responses to adenovirus infection.

Adenoviridae↗
PubMed2000

Peripheral vascular occlusive disease in renal transplant recipients: risk factors and impact on kidney allograft survival.

BACKGROUND: This study evaluated the relationship between renal transplantation and the evolution of lower extremity peripheral vascular occlusive disease (PVOD). METHODS: A total of 664 adult renal allograft recipients from 1985-1995 were retrospectively reviewed for atherosclerotic risk factors and peripheral vascular occlusive disease (PVOD). PVOD events were defined as bypass, major amputation, claudication, or percutaneous angioplasty. Follow-up ranged from 2-12 years. RESULTS: The cumulative 5- and 10-year incidences of lower extremity PVOD after renal transplantation were 4.2 and 5.9%. Eight of 14 patients (57%) with pretransplant PVOD had additional PVOD events versus de novo appearance of PVOD in 21/650 patients (3.2%; P<0.0001). In a proportional hazards model, age, preoperative PVOD, diabetes, and postoperative smoking were independent risk factors for the development of PVOD after transplantation. Recipients with lower extremity PVOD had significantly lower 10-year patient and graft survival. Increased graft failure was due to an excess of deaths with a functioning graft. A total of 34 major interventions were performed. One- and two-year limb salvage rates were 64.2 and 53.8%. CONCLUSIONS: Lower extremity PVOD after renal transplantation is associated with diminished patient survival, and affects kidney graft survival via disproportionate patient attrition. Age, preoperative PVOD, diabetes, and postoperative smoking are important risk factors. Transplantation does not appear to either accelerate or retard the progression of disease. An aggressive approach towards limb salvage in properly selected patients is justifiable.

Adult↗
PubMed1999

Renal transplantation at the University of Michigan 1964 to 1999.

The Michigan Kidney Transplant Program has existed for 35 years. Outcomes have improved dramatically as the one-year survival of cadaver kidney grafts increased from 25% to 85-90%. Patient deaths in the first year are now uncommon. Indications for renal transplantation have been extended to infants, the elderly, diabetics and to patients with other significant health problems who would not have been candidates in the past. Chronic administration of large doses of corticosteroids is no longer necessary and the associated morbidity is largely avoided. Improvements in immunosuppression, especially the introduction of cyclosporine, account for much of this progress. With success has come increasing demand. Unfortunately, the gap between the number of available donor kidneys and the number of patients listed for a cadaver transplant continues to increase rather than diminish. Greater acceptance of volunteer donation, as has occurred in our own program, will help to reduce this shortage. If the past forecasts the future, we can anticipate extraordinary advances during the next 35 years.

Actuarial Analysis↗
PubMed1998

Transthoracic, transdiaphragmatic excision of simultaneous lung and adrenal lesions.

Simultaneous adrenal and pulmonary lesions frequently present a therapeutic challenge to the thoracic surgeon. We describe 2 cases in which a transthoracic, transdiaphragmatic approach was used to establish tissue diagnosis and complete removal of gross tumor. In 1 case an intraoperative decision to perform a pneumonectomy was dictated by the tissue diagnosis of the adrenal mass, which was obtained with relative ease via this method. In both cases the morbidity of traditional approaches for adrenal operation was avoided.

Adrenal Gland Neoplasms↗
PubMed1996

The effect of clinical and biochemical donor parameters on pancreatic islet isolation yield from cadaveric organ donors.

The recovery of pancreatic islet cells from cadaveric donors for allotransplantation may depend on the functional condition of the pancreas of the donor prior to organ harvesting. We examined donor hemodynamic and biochemical parameters and their effects on the subsequent yield of islet cells after harvesting. All pancreata were flushed and preserved in University of Wisconsin (UW) solution and digested using automated method within 8 hours. In the first analysis, digestions were divided into high-yield (> 2000 IEQ/g pancreas), and low-yield (< 2000 IEQ/g) groups and donor variables were averaged for each group. Donors whose pancreata yielded > 2000 IEQ/g received significantly greater amounts of Dopamine (14.43 micrograms/kg/min vs 9.35 mg/kg/min, p = 0.05). The daily urine output between groups was also significantly different. Maximum systolic blood pressure (SBP), minimum systolic blood pressure, use of vasopressin, length of hospitalization, and maximum base deficit were compared between the two groups. Less severe hypoglycemia (lowest blood glucose 143 mg/dL vs 107 mg/dL, p = 0.02) and lower amylase levels (36.2 U vs 80.7, p = 0.07 were noted in the high-yield group. A trend towards higher islet yields was associated with lowest hourly urine output > 60 (2040 IEQ/g vs 1649 IEQ/g p = 0.09), maximum SBP > 200 (2097 vs 1673, p = 0.07, and surprisingly, lowest SBP below 80 (2013 vs 1742, p < 0.1). Amount of fluids administered prior to procurement had no influence on islet yield. In conclusion, hemodynamic variables such as urine output, systolic blood pressure, and degree of pressor support were modestly associated with successful islet isolation. The preliminary data suggest that better multifactor donor analysis is imperative for standardization and monitoring of multiorgan donors. The association of higher blood glucose levels with successful isolation may also be related to resuscitation with dextrose-containing fluids.

Adenosine↗
PubMed1995

Transplantation.

Multicenter studies have not substantiated concerns regarding the nephrotoxicity of cyclosporine. Perioperative donor-specific bone marrow transplantation has been used in human organ transplantation in an effort to induce unresponsiveness to allografts.

Humans↗