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Featured researches published by John C. Peterson.


American Journal of Kidney Diseases | 1993

Membranous glomerulonephritis in association with hepatitis C virus infection.

Rajesh K. Davda; John C. Peterson; Roy S. Weiner; Byron P. Croker; Johnson Yn Lau

Two bone marrow transplant recipients are described who developed nephrotic syndrome in association with hepatitis C virus (HCV) infection. Renal biopsies of both patients revealed stage I membranous glomerulonephritis. Detection of HCV genome was performed by nonisotopic in situ hybridization and reverse transcriptase polymerase chain reaction on paraffin-embedded renal biopsy specimens. Hepatitis C virus genome was detected by reverse transcription nested polymerase chain reaction on the RNA extracted from 15 5-microns paraffin sections. However, HCV genome was not revealed by nonisotopic in situ hybridization, which was likely due to the low copy number of HCV genomes present. These studies suggest that chronic HCV infection is associated with membranous glomerulonephritis.


Nephron | 1988

Prevention of Recurrent Urinary Tract Infections in Postmenopausal Women

Malcolm Privette; Robert Cade; John C. Peterson; Donald R. Mars

Twelve postmenopausal women who experienced frequent urinary tract infections were found to have atrophic vaginitis. Four of them who were taking sulfonamide preparations chronically also had an interstitial nephritis manifest by decreasing glomerular filtration rate and eosinophiluria. Treatment consisted of a Betadine douche daily for 1 week, administration of an appropriate nonsulfonamide antibiotic, and institution of estrogen therapy to restore glycogen deposition in the vaginal epithelium and promote return of a normal vaginal pH and bacterial flora. Prior to estrogen therapy, the frequency of infection was four per patient per year. During a follow-up observation period ranging from 2 to 8 years, there have been only four infections in the entire group. When sulfonamides were discontinued in the 4 patients with manifestations of interstitial nephritis, the eosinophiluria cleared, and the glomerular filtration rate increased significantly.


Medicine and Science in Sports and Exercise | 1984

Effects of phosphate loading on 2,3-diphosphoglycerate and maximal oxygen uptake.

Robert Cade; Michael Conte; Christian W. Zauner; Donald R. Mars; John C. Peterson; Denis Lunne; Norman Hommen; David Packer

Increased concentration of red blood cell 2,3-diphosphoglycerate (RBC 2,3-DPG) shifts the hemoglobin-oxygen dissociation curve to the right, thus theoretically allowing better oxygenation of tissues. To determine whether such a shift is physiologically significant, we investigated the effects of oral phosphate loading on several parameters including plasma phosphate concentration, RBC 2,3-DPG, hematocrit and hemoglobin concentration, maximal oxygen uptake (VO2max), and degree of lactic acidemia in 10 well-trained distance runners. After control determinations were made, either a phosphate load or a placebo was given for 3 d before the athlete was restudied. A placebo and two phosphate-loading studies were performed at weekly intervals, followed by 2 wk of rest and another post-intervention control study. Blood samples for control values were drawn before and after a standard warm-up period, after treadmill exercise at a 10% grade, and at the completion of the VO2 determination. After oral phosphate loading there was a significant increase in serum phosphate and RBC 2,3-DPG. Maximal oxygen uptake was significantly increased and correlated with the rise in RBC 2,3-DPG (r = 0.81). The increase in blood lactate after exercise on the 10% grade was attenuated during sessions which followed phosphate loading.


The American Journal of Medicine | 1987

Hepatorenal syndrome. Studies of the effect of vascular volume and intraperitoneal pressure on renal and hepatic function

Robert Cade; Herbert Wagemaker; Stephen B. Vogel; Donald R. Mars; Dennis Hood-Lewis; Malcolm Privette; John C. Peterson; Edward Schlein; Richard Hawkins; Daniel Raulerson; Kelly Campbell

Eleven patients with well-documented hepatorenal syndrome were studied by measurement of blood volume, glomerular filtration rate, renal plasma flow, plasma aldosterone concentration, renin substrate concentration, and plasma renin activity. They were then given 750 ml of stored plasma, 750 ml of fresh frozen plasma, and then an infusion of angiotensin II, in random order on successive days. Infusion of fresh frozen plasma improved function more than did stored plasma and in addition returned a very low filtration fraction toward normal. Angiotensin II infusion increased filtration fraction, but decreased glomerular filtration rate, renal plasma flow, and urine flow sharply. Patients were then given a daily infusion of 1,000 ml of fresh frozen plasma for seven to 18 days to expand the blood volume to supranormal levels as assayed by serial measurement of blood volume. Plasma aldosterone levels decreased to a normal range, glomerular filtration rate and renal plasma flow both increased, and urinary excretion of sodium and potassium both returned toward normal. The effect of intraperitoneal pressure was then studied by measuring glomerular filtration rate, renal plasma flow, pressure in the vena cava, hepatic vein free flow, and hepatic vein wedged pressure before, during, and after paracentesis to reduce the intraperitoneal pressure from 30 to 40 cm H2O to 12 to 17 cm H2O. Venous pressures moved parallel to ascitic fluid pressures, and glomerular filtration rate, renal plasma flow, and urine flow all improved sharply; then, as ascitic fluid continued to form, reducing vascular volume, urine flow, glomerular filtration rate, and renal plasma flow all decreased slowly. Six patients then underwent placement of a LeVeen shunt. Improvement in glomerular filtration rate and renal plasma flow and clinical condition was dramatic. During postoperative observation of up to two years, progressive improvement in hepatic function has occurred.


Transplantation | 1994

A preliminary report of diltiazem and ketoconazole. Their cyclosporine-sparing effect and impact on transplant outcome.

Pamela R. Patton; Mathew E. Brunson; William W. Pfaff; Richard J. Howard; John C. Peterson; Eleanor L. Ramos; Janet L. Karlix

A prospective randomized trial was conducted to compare the effect of diltiazem (DILT) with ketocon-azole (KETO) on sparing of cyclosporine dose and renal transplant outcome. Renal allograft recipients 18 years old and older were eligible for the study. Triple immunosuppression (TRIPLE) including prednisone, azathioprine, and CsA was administered to all patients. The maintenance CsA dose varied by study group. Patients were randomized to receive one of three treatment strategies: group 1—TRIPLE (CsA 8 mg/kg/day); group 2—TRIPLE (CsA 6 mg/kg/day) + DILT (60 mg b.i.d.); group 3—TRIPLE (CsA 3 mg/kg/ day) + KETO (200 mg/day). Modification of the DILT dose was allowed as needed to effect blood pressure control in group 2 patients. Mean 1-month CsA dose reductions were 30% and 60% of controls in group 2 and 3, respectively. A continued effect over time was observed in patients administered KETO but not DILT. At 1 year patients taking KETO required an average of 77% less CsA than the average dose necessary to effect similar parent CsA blood levels when no enzyme inhibitor was used. The use of KETO and DILT for 1 year allowed for 53% and 14% reductions in CsA cost, respectively. These savings include the cost of the KETO or DILT. Serum creatinines, mean arterial pressure (MAP), and incidence of liver function abnormalities were similar throughout treatment groups. The rate of rejection, time to rejection onset, and survival (GS/PS) were not different among the groups. Fungal infections were fewer in patients treated with KETO (12%) than in controls (16%) and patients randomized to DILT (19%). KETO failed to prevent Aspergillus infection in one individual. The investigation failed to identify any harmful result of treating renal allograft recipients with either DILT or KETO for the purpose of reducing CsA expense.


Transplantation | 1995

Thromboxane synthase expression in renal transplant patients with rejection

Eleanor L. Ramos; Yousri M. Barri; Byron P. Croker; William L. Clapp; John C. Peterson; Christopher S. Wilcox

Thromboxane synthase (TS) catalyzes the formation of thromboxane (TxA2) in monocytes/macrophages, platelets, and various tissues. TxA2 is likely to play a role in graft dysfunction due to its vasoconstrictive and platelet aggregatory properties. We studied the expression of TS in 7 normal native kidneys, 29 consecutive renal allograft biopsies (performed for rising serum creatinine, n = 23, and delayed graft function, n = 6), and one transplant nephrectomy specimen with severe acute rejection. TS expression was determined by immunocytochemistry using a monoclonal antibody against human TS, Kon-7. Histologic grading of the transplant biopsy specimens was based on the Banff classification. The degree of TS staining was graded in the glomeruli, interstitium, tubules and vessels from 0 to 3+. Of 29 biopsies, 13 had chronic nephropathy (CN), 6 had acute rejection (AR) with chronic nephropathy (AR/CN), 4 had acute rejection (AR), and 6 had acute tubular necrosis (ATN). TS staining of native kidneys showed sporadic interstitial cells. The biopsy and transplant nephrectomy specimens showed significant staining, predominantly in the glomeruli and interstitium. Positively staining cells appeared to be of macrophage/monocyte lineage by morphology. The mean glomerular staining grade was significantly increased in specimens with AR (2.3 +/- 0.9) and the mean interstitial staining was increased in specimens with AR/CN (2.2 +/- 0.9). Follow-up renal function 6 months post-biopsy showed that patients with higher TS staining grades had a faster decline in graft function. In conclusion, TS expression is increased in patients with acute rejection with or without chronic nephropathy and is associated with more rapid deterioration in function.


Transplantation | 1989

Incidental and purposeful random donor blood transfusion. Sensitization and transplantation.

William W. Pfaff; Richard J. Howard; Juan C. Scornik; Claire Day; Jeanne Renderer; Joan Scott; Robert S. Fennel; John C. Peterson; Daniel R. Salomon; Pamela R. Patton

We conducted a prospective study to gauge the frequency and degree of sensitization by transfusion and/or pregnancy in 797 candidates for first renal transplants. Sensitization was proportional to the number of blood transfusions. Multiple transfusions or a history of pregnancy without transfusions had similar effects on sensitization. The combination of transfusion and prior pregnancy resulted in sensitization of 1/3 of the candidates. Patients who were not sensitized and were accepted for 1-haplotype living-related donor grafts or first-cadaver donor grafts were transfused to receive a total of 5 units of packed red blood cells. Parous patients had an undue rate of antibody formation and alternate means of selecting and managing parous women are described. Nonparous candidates had a low rate of sensitization (8%) that did not prove an impediment to obtaining a transplant. Only 2% of prospective LRD graft recipients developed antibody against their intended donor. Transplant patients were generally managed with azathioprine and prednisone. One-haplotype LRD graft survival of protocol patients was 93.7% one year posttransplant, and 82.1% at 5 years. One-year CD graft survival was 77%. There was no reduction in graft survival when the interval between transfusion and transplantation exceeded one year. Random donor transfusion is effective in improving renal graft survival. Some recent multiinstitutional reports indicate a reduction or absence of the transfusion effect with current immunosuppression. Discarding blood transfusion as a preparation for transplantation may be ill-advised pending a prospective study.


American Journal of Kidney Diseases | 1988

Loss of Corticomedullary Demarcation on Magnetic Resonance Imaging: An Index of Biopsy-Proven Acute Renal Transplant Dysfunction

Kenneth R. Dunbar; Daniel R. Salomon; Juri V. Kaude; Charles S. Wingo; John C. Peterson; Byron P. Croker; Robert D. Thompson; William W. Pfaff; Richard J. Howard; C. Craig Tisher

A prospective study of 19 cadaveric renal allograft recipients with suspected graft rejection was undertaken to compare the histological findings of the renal transplant biopsy with the results of magnetic resonance imaging (MRI). All 19 patients underwent a biopsy of the transplant allograft. Biopsy results included acute cellular rejection, acute vascular rejection, chronic vascular rejection (CVR), and acute tubular necrosis (ATN). Recipients of cadaveric renal allografts with normal function served as controls. The control showed distinct corticomedullary demarcation (CMD) on T1-weighted imaging. In contrast, CMD was absent or diminished in all the patients with suspected allograft rejection. Unfortunately, the loss of CMD did not correlate with a specific biopsy diagnosis. Patients with biopsy evidence of acute and chronic rejection or ATN demonstrated loss of CMD with similar image patterns. In conclusion, MRI is capable of detecting renal allograft dysfunction, but does not permit the determination of a specific cause.


American Journal of Nephrology | 1990

Gallium Scan in the Diagnosis and Treatment of Renal Malacoplakia

Kevin A. Curran; John C. Peterson; Byron P. Croker; Walter E. Drane; C. Craig Tisher

A middle-aged female was admitted with a presumptive diagnosis of pyelonephritis that failed to respond to conventional antibiotic therapy. Multiple investigations to define the etiology of the persistent fever and accompanying acute renal failure were negative. A gallium scan revealed intense uptake in the renal parenchyma. Percutaneous renal biopsy revealed malacoplakia. Six weeks of therapy with ciprofloxacin resulted in resolution of fever, improvement in the follow-up gallium scan, and reversal of the acute renal failure.


Transplantation | 1988

Late results of renal transplantation

James J. Wynn; William W. Pfaff; Pamela R. Patton; John C. Peterson; Daniel R. Salomon; Robert S. Fennell; Juan C. Scornik; Richard J. Howard

A total of 315 (64%) of 491 primary cadaver and living-related donor transplants performed from 1975 through 1984 were still functioning at 24 months. These selected patients were examined further to assess the impact of several risk factors on late graft and patient survival. Black recipients, patients with underlying diabetes mellitus or hypertension, patients with poor renal function at 24 months, and recipients of cadaver grafts had significantly poorer long-term graft survival. Age >40, diabetes or hypertension, poor 24-month function, and cadaver donor transplantation were associated with poorer long-term patient survival. Considerable improvement in graft survival at 24 months was seen in 1980–1984 compared with the earlier period, coincident with our adoption of routine pretransplant random donor blood transfusion. In contrast, long-term graft survival in patients with functioning graft at two years did not improve significantly over the same period. Although living-related donor transplants showed greater graft and patient survival than cadaver donor grafts by univariate analysis, no such advantage was demonstrated by multivariate analysis.

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Daniel R. Salomon

Scripps Research Institute

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Eleanor L. Ramos

Brigham and Women's Hospital

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Thomas J. Fuller

University of Texas Health Science Center at San Antonio

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