Osmotic nephrosis in a renal transplant recipient.
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Biomedical subjects
Publications and source records attributed to M A Hardy.
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BACKGROUND: The aim of this study was to evaluate the effectiveness of the Edmonton Donor Scoring System for use in our much less active islet center. Because the ability to recognize an appropriate donor may help to achieve consistent and predictable success of pancreatic islet isolation, it should lead to increased effectiveness and lower cost. MATERIAL AND METHODS: Charts of 36 consecutive pancreas donors were reviewed to assess the donor points (DP). DP ranged from 0 to 100 based on donor age, body mass index, cause of death, social and medical history, hospital stay, vasopressor dosages, laboratory tests, cold ischemia time and procurement team, as well as pancreas size, consistency, fat content, damage, and quality of procurement and packing. RESULTS: Successful isolation was achieved in 39% of donors (14 of 36), a value similar to that achieved in Edmonton (40%). We used the optimal cutoff value (DP = 79) proposed by the Edmonton group. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 66%, 75%, 57%, 82% and 72%, respectively. Successful islet isolation from poor or marginal donors (DP < 49.5 and 50 to 59.5) was 0% and 28.6% respectively; it was 63% and 100% in optimal donors (DP = 80 to 89.5 and 90 to 100). We concluded that islet isolation success correlated with the previously proposed donor scoring system. CONCLUSIONS: The Donor Scoring System can be successfully implemented regardless of the level of activity of an experienced isolation center. This system permits identification of a suitable donor prior to organ processing. It may guide a center's donor selection strategy based on its goals and its budget.
INTRODUCTION: Our center has recently observed foreign carbohydrate-appearing particles (FP) on transplant postreperfusion biopsy specimens: (PRBx). METHODS: To further characterize FPs, we reviewed all renal transplant RBx (30-45 minutes) performed between September 1, 2004 and December 3, 2005. Donor, preservation, and outcome variables were collected among patients with FP. RESULTS: A total of 135 PRBx were performed (45 deceased donors [DD] and 90 live donors [LD]). Fifteen PRBx demonstrated FP. All 15 cases were DD kidneys that underwent machine perfusion (MP) on the Waters RM3 (Waters Medical Systems, Rochester, Minn, United States) with Belzer MP solution (Trans Med, Elk River, Minn, United States). Donor age was 39.8 +/- 15.7 years. Terminal creatinine level was 1.45 +/- 0.8 mg/dL. Two of 15 were flushed in situ with HTK solution (no starch). Cold ischemia time was 28.8 +/- 9.1 hours with 14.3 +/- 5.1 hours of MP. In 13 of 15 patients, perfusion parameters were excellent (flow > 100 mL; resistance < .35). CHARACTERISTICS OF FP: Particles were 10-30 mu and globular in shape. FP were not visible on hematoxylin and eosin stain, but stained strongly periodic acid-Schiff-(PAS) positive and were refractile under polarized light. FP were seen segmentally within glomerular capillaries in all cases and in peritubular capillaries in 3. In 11 of the 15 cases with FP, focal glomerular fibrin thrombi or intracapillary neutrophil margination was seen. Ten of 15 patients with FP had a biopsy within the first week with no identifiable FP. OUTCOMES: Recipient age was 45.3 +/- 11.6 years. Eight patients (53.3%) had delayed graft function. Biopsy-proven rejection occurred in 3 patients (20%). Three-month creatinine level was 1.59 +/- 0.35 mg/dL. One graft was lost to early thrombosis in a patient with a hypercoagulable state and 1 patient died of sepsis at 2 months. All remaining 13 patients are alive with excellent graft function at a median follow-up of 6.7 months (range, 3-17 months). CONCLUSIONS: Microscopic intrarenal particles may be seen on DD kidney PRBx after MP. These FPs likely originate from surgical gloves. FPs are too small to be captured by standard filters but clear spontaneously and do not have deleterious effects on renal function or outcomes.
BACKGROUND: We sought to determine whether the two-layer method (TLM) offers advantages over UW storage solution for locally procured pancreata with cold ischemia time of <8 hours for successful islet isolation. METHODS: From October 2003 through February 2005, 22 human pancreata were procured locally from cadaveric donors and preserved using UW solution (n = 11) or TLM (n = 11). RESULTS: Donor characteristics were similar in the two groups, with no statistical difference. Cold ischemia time was 4.5 +/- 0.6 (2.5 to 8) hours in the UW and 5.1 +/- 0.5 (3 to 8) hours in TLM group (P > .05). Organs preserved with TLM were exposed to PFC for 4 +/- 0.5 (2 to 7.5) hours. After TLM preservation, 8 of 11 (72%) pancreata yielded >300,000 IEQ pancreatic islets, which met all criteria for clinical transplantation; after UW cold storage, only 3 of 11 isolations were equally successful (27%) (P < .05). Mean IEQ was higher in the TLM than in the UW group: 349,000 +/- 37,000 vs 277,800 +/- 34,000; IEQ/g was also higher at 5100 +/- 760 vs 3000 +/- 570, respectively (P < .05). Islet quality, characterized by purity, viability, and insulin SI, did not differ statistically in the two groups: 67 +/- 4 vs 74 +/- 4%, 87 +/- 2 vs 83 +/- 4%, and 4 +/- 0.7 vs 4.8 +/- 1, respectively (P > .05). CONCLUSIONS: The Two Layer Method for locally procured human pancreata with cold ischemia time lower than 8 hours offers significant advantage over UW cold storage increasing the pancreatic islet isolation yield and the isolation success rate.
The widespread success of living renal transplantation has given the medical community both the opportunity and the responsibility of establishing social and ethical guidelines for the protection of donors and the treatment of recipients. While the prospects of treating more patients with organ transplant is exciting, the demand still far outpaces the supply. It is the responsibility of the transplant community and individual transplant centers to maintain a high level of integrity and ethical practice so that living renal transplantation can continue to be a viable and effective treatment for renal failure.
BACKGROUND: T cell recognition of alloMHC peptide presented by self dendritic cells via the indirect pathway of allorecognition in the thymus induces T cell tolerance. Most recently we have shown that the i.v. administration of immunodominant Wistar Furth MHC class I (RT1.Au) peptide 5- (P5) pulsed myeloid or lymphoid dendritic cells induces operational tolerance to a fully MHC-mismatched cardiac allograft. This finding led us to hypothesize that circulation of peripheral P5-activated T cells to the thymus plays an important role in the induction of acquired tolerance. METHODS: We used the adoptive transfer of 111Indium-oxine- (111In-oxine) labeled P5-pulsed syngeneic dendritic cells and in vivo P5-activated syngeneic T cells to study the role of their circulation to the thymus in the induction of transplantation tolerance. RESULTS: Intravenously administered 111In-oxine-labeled naïve DC actively migrated to and localized in the liver and spleen but did not enter the lymph nodes, bone marrow, and thymus. In vitro peptide-pulsed dendritic cells had a similar pattern of tissue localization except for a modest number of myeloid but not lymphoid DC entering the thymus. The demonstration that adoptive transfer of in vivo peptide-primed T cells induces permanent graft survival in antilymphocyte serum transiently immunosuppressed syngeneic secondary hosts led us to examine the traffic of in vivo activated T cells. Whereas naïve syngeneic T cells preferentially homed to the peripheral lymphoid organs, they did not reenter the thymus. In contrast, in vivo peptide-activated peripheral T cells migrated to and accumulated in the thymus, thus confirming that reentry of T cells to the thymus is restricted to in vivo activated T cells. Although antilymphocyte serum immunosuppression significantly reduced circulation of primed T cells to the thymus, it did not completely abolish it, as seen with gamma-irradiated primed T cells. CONCLUSION: These findings provide the first formal evidence directly linking reentry of in vivo alloMHC peptide-activated T cells to the thymus with the induction and possibly maintenance of acquired antigen-specific tolerance. Our results suggest that the thymus is open to a two-way traffic with the periphery and may function as a repository of immunological memory.
BACKGROUND: Our most recent observation that i.v. injection of Wistar-Furth (WF) major histocompatibility complex Class I peptide 5 (P5)-pulsed self-myeloid or lymphoid dendritic cells (DC) induces transplantation tolerance suggests that adoptive transfer of in vivo allopeptide-primed host T cells might induce acquired tolerance through their interaction with thymic DC. METHODS: To examine this hypothesis, host myeloid DC cultured in rat granulocyte/macrophage colony stimulating factor and interleukin 4 were pulsed in vitro with P5 and injected intravenously into syngeneic ACI rats. The T cells primed to P5 via the indirect pathway of allorecognition were harvested 7 days later and administered by either intravenously or intrathymically into syngeneic ACI recipients of WF cardiac allografts. RESULTS: Syngeneic T cells obtained from the spleen of P5-primed rats had a high mixed lymphocyte reaction proliferative response to P5 presented by self-DC. I.v. administration of 2x107 P5-primed alloreactive purified host splenic T cells alone on day -7 significantly (P<0.001) prolonged cardiac allograft survival from 10.5+/-1.0 days to 18.6+/-1.8 days in the WF-to-ACI rat combination. I.v. injection of P5-activated host T cells combined with 0.5 ml antilymphocyte serum (ALS)-transient immunosuppression on day -7 led to 100% donor-specific permanent graft survival (>200 days). Thymectomy before i.v. injection of P5-activated syngeneic T cells led to acute graft rejection, suggesting that the homing of in vivo activated T cells to the host thymus might play a role in the induction of tolerance. To further define the role of the recipient thymus in this model, we examined the effects of intrathymic (i.t.) injection of P5-primed alloreactive T cells on graft survival and found that i.t. administration of the P5-primed T cells on day -7 alone significantly prolonged graft survival (15.0+/-0.7 days) and when combined with 0.5 ml ALS led to donor-specific permanent graft survival. The long-term unresponsive recipients permanently (>100 days) accepted second-set donor-specific cardiac allografts but not third-party (Lewis) grafts. CONCLUSIONS: These findings demonstrate that the adoptive transfer of splenic T cells primed to an indirectly presented donor peptide induces transplantation tolerance in a transiently immunosuppressed secondary syngeneic recipient. Our data suggest that the interaction of thymic DC with activated peripheral T cells induces alloantigen (Ag)-specific T-cell tolerance by either inactivation or deletion of alloreactive T cells in the thymus. This observation provides the first formal evidence that the interaction between thymic DC and activated peripheral T cells that continuously circulate through the thymus plays an important role in the induction and maintenance of Ag-specific tolerance.
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Pancreatic islet transplantation remains a promising approach to the treatment of type 1 diabetes. Unfortunately, graft failure continues to occur because of immunologic rejection, despite the use of potent immunosuppressive agents. It is therefore reasoned that induction of peripheral tolerance by the use of self-dendritic cells (DCs) as a vehicle to deliver specific target antigens to self-T-cells without ex vivo manipulation of the recipient is an attractive strategy in the treatment of type 1 diabetes. The finding that intrathymic inoculation of an immunodominant WF major histocompatibility complex (MHC) Class I (RT1.A(u)) peptide five (P5) or P5-pulsed host myeloid DCs induces acquired thymic tolerance raises the possibility that adoptive transfer of allopeptide-primed host myeloid or lymphoid DCs might induce transplant tolerance. To address this hypothesis, we studied the effects of intravenous transfer of in vitro P5-pulsed syngeneic myeloid DCs or in vivo P5-primed syngeneic lymphoid (thymic) DCs on islet survival in the WF-to-ACI rat combination. In vivo primed thymic DCs isolated from ACI rats given intrathymic inoculation of P5 for 2 days were capable of in vitro restimulation of in vivo P5-primed T-cells (memory cells). In the first series of studies, we showed that intravenous-like intrathymic-inoculation of in vitro P5-pulsed host myeloid DCs induced donor-specific permanent acceptance of islets in recipients transiently immunosuppressed with antilymphocyte serum (ALS). We next examined whether thymic DCs isolated from animals that had been previously intrathymically inoculated with P5 could induce T-cell tolerance. The results showed that intravenous adoptive transfer of in vivo P5-primed thymic DCs led to donor-specific permanent acceptance of islets in recipients transiently immunosuppressed with ALS. This finding suggested that the thymic DCs take up and present P5 to developing T-cells to induce T-cell tolerance, thus providing evidence of a direct link between indirect allorecognition and acquired thymic tolerance. The second series of studies examined the mechanisms involved in this model by exploring whether in vivo generation of peptide-specific alloreactive peripheral T-cells by intravenous inoculation of P5-pulsed self-DCs was responsible for the induction of T-cell tolerance. Intrathymic inoculation of splenic T-cells obtained from syngeneic ACI rats primed with intravenous injection of P5-pulsed DCs with a high in vitro proliferative response to P5 in the context of self-MHC induced donor-specific permanent acceptance of islets from WF donors. In addition, the clinically relevant model of intravenous injection of P5-activated T-cells combined with transient ALS immunosuppression similarly induced transplant tolerance, which was then abrogated by thymectomy of the recipient before intravenous injection of the activated T-cells. These data raise the possibility that circulation of peptide-activated T-cells to the host thymus plays a role in the induction and possibly the maintenance of T-cell tolerance in this model. Our findings suggest that intravenous administration of genetically engineered host DCs expressing alloMHC peptides might have therapeutic potential in clinical islet transplantation for the treatment of autoimmune diabetes.
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We have studied the effects of adoptive transfer of host thymic dendritic cells pulsed with immunodominant WF Class I peptide 5 (residues 93-109) on cardiac allograft survival in the WF-to-ACI rat combination. Our results showed that, whereas intrathymic inoculation of WF peptide 5-pulsed ACI thymic dendritic cells alone on day -7 did not prolong graft survival, similar treatment combined with 0.5 mL antilymphocyte serum (ALS) led to 100% permanent acceptance (> 200d) of donor-specific cardiac allografts. Extension of our study to systemic administration of peptide 5-pulsed host thymic dendritic cells confirmed that intravenous injection of peptide 5-pulsed self thymic dendritic cells combined with ALS transient immunosuppression resulted in 100% permanent donor-specific graft survival (> 200d). These results were reproducible in a clinically relevant model using intravenous injection of peptide-pulsed host myeloid dendritic cells. In contrast, thymectomy prior to adoptive transfer of peptide-pulsed host dendritic cells resulted in acute graft rejection at times equivalent to rejection in thymectomized controls. The long-term unresponsive recipients challenged with second-set grafts accepted permanently (> 100d) donor-type (WF) but not third party (Lewis) cardiac allografts. This study suggests that intravenous administration of genetically engineered dendritic cells expressing donor MHC molecules has the potential of inducing transplant tolerance.
BACKGROUND: Anti-thymocyte globulin (ATG) is used frequently as induction therapy in renal transplant recipients. It has been standard practice that the various polyclonal anti-lymphocyte preparations be administered via central line, vascular shunt, or arteriovenous fistula to avoid thrombophlebitis. METHODS: We have safely administered equine ATG (Atgam) via peripheral veins since 1978. We now retrospectively review recent experience with 83 patients transplanted between 1993 and 1998 who received Atgam induction via peripheral vein. Heparin 1000 U and Solucortef 20 mg were added to the infusion. Acetaminophen and diphenhydramine were given before infusion. RESULTS: Only two of 83 patients developed mild edema/erythema at or around the i.v. site. These reactions responded promptly to local management with warm soaks. No phlebitis or symptomatic venous thrombosis occurred in any patients. CONCLUSIONS: Equine ATG can be safely administered via peripheral vein infusion. Its use does not require continued hospitalization or placement of a central line. Peripheral vein infusion is safe, convenient, and economical.
BACKGROUND: As T-cell receptor-major histocompatibility complex (MHC) class I/self peptide interaction regulates T-cell development in the thymus, we reasoned that presentation of peptides by self dendritic cells (DC) to developing T cells in the thymus might induce acquired thymic tolerance. This hypothesis is based on the finding that intrathymic injection of allopeptides in the adult animal induces acquired tolerance. To examine this hypothesis, we studied the effects of intrathymic (IT) injection of a single immunodominant Wistar-Furth (WF) MHC class I (RT1.Au) peptide-pulsed host DC on islet allograft survival in the WF-to-ACI rat combination. METHODS: Bone marrow-derived ACI DC expressing MHC class I and II, OX62, and ED2 present allopeptides to naive and specifically peptide-primed syngeneic T cells in mixed lymphocyte reaction. Host DC pulsed with RT1.Au peptide 5 (residues 93-109) were injected into the thymus of streptozotocin-induced diabetic ACI that were transplanted 7 days later with donor-type (WF) or third-party (Brown Norway [BN]) islets. RESULTS: Whereas IT injection of 300 microg of peptide 5 alone led to normoglycemia and permanent islet survival in three of six diabetic ACI recipients, similar treatment combined with simultaneous intraperitoneal injection of 0.5 ml of anti-lymphocyte serum (ALS) on day -7 led to 100% permanent islet allograft survival (>200 days) compared to a mean survival time of 15.0+/-2.3 days in controls treated with ALS alone. In contrast, similarly prepared animals rejected the third-party (BN) islets in an acute fashion. To address the question of indirect allorecognition in acquired thymic tolerance, we examined the effect of peptide-pulsed host DC on graft survival. Whereas IT injection of peptide-pulsed host DC alone resulted in permanent islet survival in two of five animals, IT injection of peptide-pulsed host DC combined with 0.5 ml of ALS induced 100% donor-specific permanent islet allograft survival in the WF-to-ACI rat combination. These results suggest that thymic DC take up, process, and present the administered peptide to the developing T cells by the indirect allorecognition pathway in the induction of acquired thymic tolerance. CONCLUSION: We have demonstrated a novel approach to inducing transplant tolerance to islet allografts with IT injection of allopeptide-pulsed host DC. This finding suggests that immunization strategies using DC expressing MHC allopeptides or peptide analogue might be potentially useful in the treatment of autoimmune diabetes mellitus.
Successful clinical transplantation of the upper extremity has been performed in several centers. In contrast with the recipients of other immediately vascularized organ allografts, the candidate for upper extremity transplantation has been, at least during the initial effort, a healthy patient. Although it is clear that composite tissue transplantation (CTA) is a form of allografting that behaves in many ways similarly to immediately vascularized organ allografts, the issue of developing immunologic understanding of such new allografts, awaits greater clinical experience. A summary of the immunosuppressive management of the patients who received hand allografts, with a view to explore the immunologic advantages and disadvantages as well as graft toxicity of the commonly used agents, is reported. This brief overview of the immunologic considerations in CTA is presented with the purpose of summarizing the main issues that contribute to the ultimate goal of achieving tolerance. These considerations include (1) the recipients before transplantation, (2) the donors including possible pretreatment, (3) immunosuppression for induction, maintenance, and treatment of acute rejection and its diagnosis, and (4) future potential for tolerance induction.
OBJECTIVES: As responsibility for financial security in retirement becomes more individualized, understanding the distribution and determinants of savings behavior grows in importance. Employed men and women often gain access to their pension assets when they change jobs. In this study gender differences in pre-retirement access to and disposition of accumulated pension assets are examined. METHODS: The authors used data from the Health and Retirement Study to model pension participation, disposition of pension assets, and use of cash settlements derived from a pension plan in a previous job. Logit models provided estimates of gender differences in access to pensions and the preservation of pension funds for retirement. RESULTS: Women were less likely to have participated in employer-sponsored pension plans; more likely to cash out accumulated pension assets when they changed jobs; and, when job changes occurred at relatively young ages, equally likely to spend the settlement. However, by their late 40s, women were more likely to save the settlement, a net gender difference that increased with age at which the settlement was received. DISCUSSION: The structure of employment compensation continues to place women at a disadvantage. Gender differences in earnings and fringe benefits not only affect current financial status, but also cast a shadow over future financial security. Although the gender gap in pension coverage has been reduced, women with pensions have access to lower benefits and less in accumulated assets. As these continuing deficits are addressed, enhancing women's tendency to save pension assets for retirement can help them build financial security.
Job satisfaction in the workplace affects absenteeism, turnover, and performance. We conducted a cross-sectional study of 201 nursing personnel to assess satisfaction among nursing staff at a military hospital in the southwestern United States. Participants completed a self-administered survey in which they rated professional status, autonomy, pay, organizational policies, task requirements, and interaction by importance and satisfaction. Autonomy, professional status, and pay were the most important factors and organizational policies was the least important factor. Military staff were slightly more satisfied with staff interactions than civilian staff. Nursing personnel working in specialty care units were significantly more satisfied with interactions and professional status, but they valued organizational policies less than those working in general units. Professionals were significantly more satisfied with pay and autonomy, whereas nonprofessionals were more satisfied with task requirements and professional status.
OBJECTIVE: To assess the efficacy of lamotrigine, a novel antiepileptic drug that inhibits glutamate release, to retard disease progression in Huntington disease (HD). BACKGROUND: Excitatory amino acids may cause selective neuronal death in HD, and lamotrigine may inhibit glutamate release in vivo. METHODS: A double-blinded, placebo-controlled study was conducted of 64 patients with motor signs of less than 5 years' duration who were randomly assigned to either placebo or lamotrigine and assessed at 0 (baseline), 12, 24, and 30 months. The primary response variable was total functional capacity (TFC) score. Secondary response variables included the quantified neurological examination and a set of cognitive and motor tests. Repeated fluorodeoxyglucose measurements of regional cerebral metabolism using PET also were included. RESULTS: Fifty-five patients (28 on lamotrigine, 27 on placebo) completed the study. Neither the primary response variable nor any of the secondary response variables differed significantly between the treatment groups. Both the lamotrigine and the placebo group deteriorated significantly on the TFC, in the lamotrigine group by 1.89 and the placebo group by 2.11 points. No effect of CAG size on the rate of deterioration could be detected. CONCLUSIONS: There was no clear evidence that lamotrigine retarded the progression of early Huntington disease over a period of 30 months. However, more patients on lamotrigine reported symptomatic improvement (53.6 versus 14.8%; p = 0.006), and a trend toward decreased chorea was evident in the treated group (p = 0.08). The study also identified various indices of disease progression, including motor tests and PET studies, that were sensitive to deterioration over time.
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