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M L Jordan

Publications and source records attributed to M L Jordan.

At least 55 records · Page 3Linked to original sources
PubMed1997

Acute renal allograft rejection in patients with Epstein-Barr virus associated post-transplant lymphoproliferative disorder.

BACKGROUND: There is a reciprocal relationship between post-transplant lymphoproliferative disorder (PTLD) and rejection: aggressive treatment of rejection can result in PTLD, while treatment of PTLD by reducing immunosuppression can result in recrudescence of rejection. The literature on the relationship between PTLD and rejection episodes is limited. METHODS: The clinical course and outcome of rejection episodes occurring prior to and following a diagnosis of PTLD were studied in 20 renal transplant recipients. RESULTS: The diagnosis of PTLD was preceded by rejection in 12/20 (60%) patients. OKT3 treatment was associated with early onset PTLD, which involved the allograft in 6/7 patients (86%). The risk of rejection following reduced immunosuppression was 7/14 (50%). Post-PTLD rejection left untreated led to graft loss in 3 patients. The remaining 4 patients responded satisfactorily to anti-rejection therapy. CONCLUSIONS: Reduction of immunosuppression for PTLD is frequently, but not invariably, complicated by rejection. The clinical outcome of PTLD does not correlate with the occurrence or reversibility of rejection episodes.

Adult↗
PubMed1996

Tacrolimus in pediatric renal transplantation.

Tacrolimus was used as the primary immunosuppressive agent in 69 pediatric renal transplantations between December 17, 1989, and June 30, 1995. Children undergoing concomitant or prior liver and/or intestinal transplantation were excluded from analysis. The mean recipient age was 10.3+/-5.0 years (range, 0.7-17.5 years). Seventeen (24.6%) children were undergoing retransplantation, and six (8.7%) had a panel reactive antibody level of 40% or higher. Thirty-nine (57%) cases were with cadaveric kidneys, and 30 (43%) were with living donors. The mean donor age was 28.0+/-14.7 years (range, 1.0-50.0 years), and the mean cold ischemia time for the cadaveric kidneys was 27.0+/-9.4 hr. The antigen match was 2.7+/-1.2, and the mismatch was 3.1+/-1.2. All patients received tacrolimus and steroids, without antibody induction, and 26% received azathioprine as well. The mean follow-up was 32+/-20 months. One- and 4-year actuarial patient survival rates were 100% and 95%. One- and 4-year actuarial graft survival rates were 99% and 85%. The mean serum creatinine level was 1.2+/-0.8 mg/dl, and the calculated creatinine clearance was 82+/-26 ml/min/1.73 m2. The mean tacrolimus dose was 0.22+/-0.14 mg/ kg/day, and the level was 9.5+/-4.8 ng/ml. The mean prednisone dose was 2.1+/-4.9 mg/day (0.07+/-0.17 mg/kg/day), and 73% of successfully transplanted children were off prednisone. Seventy-nine percent were not taking any antihypertensive medications. The mean serum cholesterol level was 158+/-54 mg/dl. The incidence of delayed graft function was 4.3%. The incidence of rejection was 49%, and the incidence of steroid-resistant rejection was 6%. The incidence of rejection decreased to 27% in the most recent 26 cases (January 1994 through June 1995). The incidence of new-onset diabetes was 10.1%; six of the seven affected children were able to be weaned off insulin. The incidence of cytomegalovirus disease was 13%, and that of posttransplant lymphoproliferative disorder was 10%; the incidence of posttransplant lymphoproliferative disorder in the last 40 transplants was 5% (two cases). All of the children who developed posttransplant lymphoproliferative disorder are alive and have functioning allografts. Based on this data, we believe that tacrolimus is a superior immunosuppressive agent in pediatric renal transplant patients, with excellent short- and medium-term patient and graft survival, an ability to withdraw steroids in the majority of patients, and, with more experience, a decreasing rate of rejection and viral complications.

Adolescent↗
PubMed1996

Graft hyporeactivity induced by donor-specific bone marrow.

Much interest has recently focused on administration of donor cells with organ transplantation to improve graft outcome. However, whether donor cell administration actually confers donor-specific (DS) hyporeactivity is unknown. The intra-graft events after DS bone marrow (BM) infusion were therefore examined in an in vivo sponge matrix allograft model. Recipient C57BL/6J (B6,H2b) mice (five per group) received either media alone, 10(7) syngeneic (B6), or allogeneic (DBA/2J,H2d) BM cells intravenously. Seven days later, a sponge matrix allograft containing 10(7) allogeneic (DBA) splenocytes was implanted. On various days after grafting, graft-infiltrating cells were tested for in vitro cytotoxicity by 51Cr release assay. Previous DSBM infusion significantly reduced intragraft allospecific cytolytic T-cell (CTL) activity compared with mice receiving syngeneic BM or media alone (3.5 +/- 5.1% vs. 46.2 +/- 13.3% and 47.9 +/- 13.5% at 100:1 E:T, respectively, P < 0.001). Time course studies showed that DSBM impaired allospecific CTL activity whether given on day -10 (3.3% at 100:1 E:T), day -7 (2.2%), day -2(7.7%), or day 0 (6.5%), but was not as effective when given on day +7 (27.1%). Flow cytometry of graft-infiltrating cells on day +12 showed a decreased percentage of CD8+ cells after DSBM, compared with syngeneic BM or media alone (13.1% vs. 38.0% and 36% respectively, P = 0.01), but the percentage of CD4+ cells was similar in all groups (5.5%, 6.9%, and 4%, respectively). Thus, (1) DSBM inhibits allospecific CTL development in the allograft, (2) decreased intra-graft CTL activity after DSBM correlates with a decreased percentage of intragraft CD8+ cells, and (3) DSBM induces hyporeactivity up until the day of the allograft placement, but not thereafter. DSBM may, thus, induce graft hyporeactivity by impairing intragraft immune activation.

Animals↗
PubMed1996

"Suboptimal" kidney donors: the experience with tacrolimus-based immunosuppression.

Female, pediatric, and older donors have been associated with inferior graft survival after renal transplantation. We analyzed these three subgroups in 397 patients receiving tacrolimus-based immunosuppression. There were no differences in recipient age, incidence of retransplantation, or percentage of sensitized patients. Female donors, compared with male donors, were associated with comparable 1- and 3-year patient survival rates (96% and 93% vs. 95% and 92%, respectively) and comparable 1- and 3-year graft survival rates (90% and 80% vs. 88% and 81%, respectively). Renal function was also similar. Recipients of pediatric en bloc kidneys, when compared with recipients of other cadaveric kidneys, also had comparable 1- and 3-year patient survival rates (94% and 94% vs. 95% and 91%, respectively) and comparable 1- and 3-year graft survival rates (84% and 84% vs. 89% and 79%, respectively). Renal function was better in recipients of en bloc kidneys, with a mean serum creatinine level of 1.4+/-1.8 mg/dl vs. 2.0+/-1.5 mg/dl (P=0.01). In contrast to the first two subgroups, donors over 60 years of age, when compared with donors under 60 years of age, were associated with worse 1- and 3-year patient survival rates (88% and 80% vs. 96% and 94%, respectively; P<0.03) and worse 1- and 3-year graft survival rates (74% and 62% vs. 91% and 83%, respectively; P<0.0001). Renal function was worse in the older donor group, with a serum creatinine level of 2.7+/-1.2 mg/ml vs. 1.9+/-1.5 mg/dl (P=0.01). We conclude that, under tacrolimus-based immunosuppression, kidneys from female or very young pediatric donors are not associated with adverse outcomes, whereas kidneys from donors over 60 years of age are associated with inferior outcomes.

Adult↗
PubMed1996

The use of tacrolimus in renal transplantation.

Tacrolimus (FK 506) is a novel immunosuppressive agent that has been in clinical use for solid organ transplantation since 1989. Early clinical trials of tacrolimus in liver, heart, kidney, lung, and intestinal transplantation at the University of Pittsburgh have demonstrated it to be a safe and effective agent with several potential advantages over existing immunosuppressive drugs. More recently, phase I and II multicenter trials of tacrolimus for renal transplantation have been performed; however, data are not yet available from these trials. Our experience with this drug has demonstrated excellent 1- and 2-year actuarial graft survival rates of 89% and 83%, respectively, in adult renal transplantation and 1- and 3-year graft survival rates of 98% and 85%, respectively in pediatric renal transplantation. A major advantage of tacrolimus noted in these trials was the ability to discontinue steroid therapy in approximately 50% of the patients. Tacrolimus has also shown efficacy as a rescue agent for renal allograft rejection failing conventional therapy in 74% of cases. This paper expands on these observations and focuses on the experience we have gained with the use of tacrolimus at our institution over the last 6 years.

Graft Survival↗
PubMed1995

A prospective randomized trial of FK506-based immunosuppression after renal transplantation.

A group of 204 adult patients was entered into a prospective, randomized trial comparing FK506/prednisone with FK506/azathioprine/prednisone after renal transplantation between August 1, 1991 and October 11, 1992. The purpose of the study was to see if the addition of azathioprine would reduce the incidence of rejection and improve graft survival. The recipient population was unselected, with 61 (30%) patients undergoing retransplantation, 37 (18%) having a panel-reactive antibody greater than 40%, and 33 (16%) over 60 years of age. The mean recipient age was 43.8 +/- 13.7 years (range 17.6-78). The mean donor age was 34.0 +/- 20.1 years (range 0.3-75); 13% of the cadaveric kidneys were from pediatric donors less than 3 years of age and were transplanted en bloc. The mean cold ischemia time was 31.4 +/- 8.4 hr. Living donors were the source of 13% of the kidneys. The mean follow-up was 22 +/- 4 months (range 12-29). Overall one-year actual patient survival was 94%. Overall one-year actual graft survival was 87%. Patients starting on double therapy had a one-year actual patient survival of 96% and a one-year actual graft survival of 92%. Patients starting on triple therapy had a one-year actual patient survival of 91% (P = ns compared with double therapy), and a one-year actual graft survival of 82% (P < 0.02, compared with double therapy). Overall results with first cadaver transplants included a one-year actual patient survival of 94% and one-year actual graft survival of 88%, with no differences between double and triple therapy. The overall incidence of rejection was 48%, with 54% in the double therapy group and 41% in the triple therapy group (P < .07). The incidence of steroid-resistant rejection requiring antilymphocyte therapy (OKT3 or ATGAM) was 13%, and was not different between the double and triple therapy groups. The mean serum creatinine was 1.8 +/- 0.8 mg/dl. The mean BUN was 33 +/- 21 mg/dl, with no significant difference between the therapy groups. The mean serum cholesterol was 192 +/- 49 mg/dl. A total of 56% of the patients are off prednisone, and 35% of the patients are not taking any antihypertensive medications. Other complications included cytomegalovirus--14%; new-onset diabetes--16% (half of which was reversible); and posttransplant lymphoproliferative disorder--1%.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1995

FK506 in pediatric kidney transplantation--primary and rescue experience.

Between 14 December 1989 and 17 December 1993, 43 patients undergoing kidney transplantation alone at the Children's Hospital of Pittsburgh received FK506 as the primary immunosuppressive agent. The mean recipient age was 10.2 +/- 4.8 years (range 0.7-17.4 years), with 7 (16%) children under 5 years of age and 2 (5%) under 2 years of age. Fifteen (35%) children underwent retransplantation, and 5 (12%) had a panel-reactive antibody level greater than 40%. Twenty-two (51%) transplants were with cadaveric donors and 21 (49%) were with living donors. The mean follow-up was 25 +/- 14 months; there were no deaths; 1- and 3-year actuarial graft survival was 98% and 85%. The mean serum creatinine and blood urea nitrogen were 1.2 +/- 0.6 mg/dl and 26 +/- 11 mg/dl; the calculated creatinine clearance was 75 +/- 23 ml/min per 1.73 m2. Twenty-four (62%) patients have been successfully withdrawn from steroids and 24 (62%) require no anti-hypertensive medication. Improved growth was seen, particularly in pre-adolescent children off steroids. Between 28 July 1990 and 2 December 1993, 24 children were referred for rescue therapy with FK506, 14.6 +/- 16.4 months (range 1.1-53.2 months) after transplantation. Nineteen (79%) were referred because of resistant rejection; 4 (17%) were referred because of proteinuria; 1 (4%) was switched because of steroid-related obesity. There were no deaths; 1- and 2-year graft survival was 75% and 68%; 17 (71%) patients were successfully rescued, including 1 of 2 patients who arrived on dialysis; 4 (24%) of the successfully rescued patients were weaned off steroids.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Regulation of inducible nitric oxide production by intracellular calcium.

BACKGROUND: Because increased nitric oxide (NO) production during sepsis can be detrimental to the host, inhibition of NO synthesis by various antagonists has been proposed as a therapeutic option. However, none of these approaches has addressed the possible regulation of inducible NO synthesis (iNOS) by endogenous intracellular signaling mechanisms. The purpose of our study was to determine whether intracellular calcium ([Ca2+]i) regulates iNOS. METHODS: The macrophage cell line RAW 264.7 cells stimulated to produce NO were cultured in the presence or absence of the calcium ionophore A23187, ionomycin, or the Ca(2+)-adenosine triphosphatase inhibitor thapsigargin. Supernatants and total cellular RNA were recovered for measurement of iNOS messenger RNA (Northern blot) and NO2- (stable end product of NO), respectively. Simultaneous measurement of [Ca2+]i was performed by fluorescence spectrophotometry. RESULTS: The calcium ionophore A23187, ionomycin, and thapsigargin all produced a dose-dependent inhibition of NO end product and iNOS messenger RNA (confirmed by densitometry) with a simultaneous increase in [Ca2+]i, confirmed by fluorescence spectrophotometry. This could not be reversed by exogenous L-arginine and was not observed if these agents were added beyond 0 hours of culture. CONCLUSIONS: Although iNOS is traditionally viewed as calcium independent, these data clearly show that [Ca2+]i regulates iNOS messenger RNA induction and end product synthesis. Endogenous cellular second messenger may thus be important in autoregulation of NO synthesis. Alternatives to pharmacologic or antagonist inhibition of NO deserve further investigation.

Arginine↗
PubMed1995

The role of a substance abuse consultation team in a trauma center.

OBJECTIVE: Trauma is a leading cause of morbidity and mortality in the U.S., and substance abuse makes an enormous contribution to this problem as well as to the increased cost of health care. A substance abuse consultation (SAC) team was developed to evaluate and intervene with trauma victims who are suspected of having problems with alcohol and/or other drugs. This study was undertaken to determine the effectiveness of this service. METHOD: This study is a retrospective review of 100 consecutive trauma admissions who were felt to be at high risk for substance abuse and were referred to the SAC team for evaluation and intervention. This study was undertaken in a tertiary care teaching hospital in a cooperative effort between the trauma center and the addictions program. RESULTS: All 100 patients were diagnosed with psychoactive substance use disorders and 78 were referred for alcohol and other drug rehabilitation. Of these patients, 62% accepted a referral for drug and alcohol treatment. CONCLUSIONS: From these preliminary data, it appears that a SAC team may be effective in intervening with hospitalized trauma patients who have alcohol and other drug problems.

Accidents, Traffic↗
PubMed1995

The superiority of tacrolimus in renal transplant recipients -- the Pittsburgh experience.

Tacrolimus is a superior immunosuppressive agent in patients undergoing renal transplantation. In adults, the 1- and 3-year actuarial patient survivals were 95% and 92%, and the 1- and 3-year actuarial graft survivals were 89% and 80%. For first cadaver kidneys, the 1- and 3-year actuarial graft survivals were 91% and 82%, with a projected half-life of 11.9 years. Sixty-nine percent of successfully transplanted patients were weaned off steroids. In pediatric patients, the 1- and 4-year actuarial patient survivals were 100% and 96%, and the 1- and 4-year actuarial graft survivals were 99% and 85%. Seventy-three percent of successfully transplanted children were weaned off steroids. Tacrolimus was also useful as a rescue agent, with an initial success rate of 74%. Tacrolimus has been used successfully in kidney/ pancreas transplantation, with 100% patient, 95% kidney, and 79% pancreas graft survival. Tacrolimus should be considered the immunosuppressive agent of choice in renal transplantation.

Adolescent↗