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Transplanted Organs (transplanted + organ)
Selected AbstractsProcess of Care Events in Transplantation: Effects on the Cost of HospitalizationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2010N. N. Egorova Deviations in the processes of healthcare delivery that affect patient outcomes are recognized to have an impact on the cost of hospitalization. Whether deviations that do not affect patient outcome affects cost has not been studied. We have analyzed process of care (POC) events that were reported in a large transplantation service (n = 3,012) in 2005, delineating whether or not there was a health consequence of the event and assessing the impact on hospital resource utilization. Propensity score matching was used to adjust for patient differences. The rate of POC events varied by transplanted organ: from 10.8 per 1000 patient days (kidney) to 17.3 (liver). The probability of a POC event increased with severity of illness. The majority (81.5%) of the POC events had no apparent effect on patients' health (63.6% no effect and 17.9% unknown). POC events were associated with longer length of stay (LOS) and higher costs independent of whether there was a patient health impact. Multiple events during the same hospitalization were associated with the highest impact on LOS and cost. POC events in transplantation occur frequently, more often in sicker patients and, although the majority of POC events do not harm the patient, their effect on resource utilization is significant. [source] Prevention of toxoplasmosis in transplant patientsCLINICAL MICROBIOLOGY AND INFECTION, Issue 12 2008F. Derouin Abstract Toxoplasmosis is a life-threatening opportunistic infection that affects haematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT) recipients. Its incidence in these patients is closely related to the prevalence of toxoplasmosis in the general population, which is high in Europe. In SOT recipients, toxoplasmosis results mainly from transmission of the parasite with the transplanted organ from a Toxoplasma -seropositive donor to a Toxoplasma -seronegative recipient. This risk is high in cases of transplantation of organs that are recognized sites of encystation of the parasite, e.g. the heart, and is markedly lower in other SOT recipients. Clinical symptoms usually occur within the first 3 months after transplantation, sometimes as early as 2 weeks post transplant, and involve febrile myocarditis, encephalitis or pneumonitis. In HSCT recipients, the major risk of toxoplasmosis results from the reactivation of a pre-transplant latent infection in seropositive recipients. The median point of disease onset is estimated at 2 months post transplant, with <10% of cases occurring before 30 days and 15,20% later than day 100. Toxoplasmosis usually manifests as encephalitis or pneumonitis, and frequently disseminates with multiple organ involvement. Diagnosis of toxoplasmosis is based on the demonstration of parasites or parasitic DNA in blood, bone marrow, cerebrospinal fluid, bronchoalveolar lavage fluid or biopsy specimens, and serological tests do not often contribute to the diagnosis. For prevention of toxoplasmosis, serological screening of donors and recipients before transplantation allows the identification of patients at higher risk of toxoplasmosis, i.e. seropositive HSCT recipients and mismatched (seropositive donor/seronegative recipients) SOT recipients. Preventing toxoplasmosis disease in those patients presently relies on prophylaxis via prescription of co-trimoxazole. [source] Activity of CuZn-superoxide dismutase, catalase and glutathione peroxidase in erythrocytes in kidney allografts during reperfusion in patients with and without delayed graft functionCLINICAL TRANSPLANTATION, Issue 1 2006L Doma Abstract:, Background:, Generation of reactive oxygen species (ROS) is the main mechanism involved in the ischemic/reperfusion damage of the transplanted organ. Oxygen burst is a trigger for complex biochemical events leading to generation of oxygenated lipids and changes in microcirculation. Many markers have been researched to prove the presence of ROS in the transplanted tissue. Some of them, like superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) are considered to play a major role in graft protection against oxygen stress during reperfusion. Methods:, The aim of this study was to examine the changes of SOD1, CAT and GPx activity in erythrocytes during the first minutes after total graft reperfusion. Forty patients undergoing kidney transplantation at our center were assigned to two groups: with or without delayed graft function (DGF). Before anastomosing kidney vessels with recipient's iliac vessels, the ,0' blood sample was taken from the iliac vein. Next blood samples I, II and III were taken from the graft's renal vein. The reperfusion of the transplanted kidney was evaluated precisely with the thermovision camera. Erythrocyte SOD1, CAT and GPx activity was measured with a spectrophotometric method. Results:, We did not observe statistically significant changes in SOD1, CAT and GPx activity in erythrocytes during the early phase of reperfusion in patients with and without DGF. Conclusions:, Erythrocyte-antioxidative system in graft's vein remain stable during the early phase of reperfusion. The results of the study suggest that further studies on extracellular enzymes are required for the assessment of antioxidant system in the conditions of ischemia/reperfusion. [source] Simultaneous administration of a low-dose mixture of donor bone marrow cells and splenocytes plus adenovirus containing the CTLA4Ig gene result in stable mixed chimerism and long-term survival of cardiac allograft in ratsIMMUNOLOGY, Issue 2 2003Yongzhu Jin Summary T-cell costimulatory blockade combined with donor bone marrow transfusion may induce mixed chimerism, rendering robust tolerance in transplanted organs and cells. However, most protocols entail high doses of donor bone marrow cells (BMCs) or repeated administration of costly agents that block costimulatory pathways, thus delaying clinical development. To circumvent these shortcomings, we developed a strategy in which the dosage of donor BMCs was reduced but compensated by donor splenocytes (SPLCs). Furthermore, repeated administration of costly agents was replaced with a single injection of adenovirus expressing a gene of interest. In rat cardiac transplantation models, cardiac allografts from DA (RT-1a) rats were transplanted heterotopically into the abdomen of LEW (RT-11) recipient rats. Immediately after cardiac transplantation, an adenovirus vector (AdCTLA4Ig; 5 × 109 plaque-forming units) containing the gene for CTLA4Ig was administered to recipients (n = 6) simultaneously with a low dose of donor BMCs (1 × 108/rat) and SPLCs (5 × 107/rat) via the portal vein. The treated LEW recipient rats developed long-lasting mixed chimerism (>10% at >100 days) and exhibited long-term cardiac allografts (mean survival time of > 200 days) compared with control recipients. Moreover, recipients displaying long-lasting mixed chimerism accepted subsequent donor skin allografts while promptly rejecting third-party skin allografts. These results suggest that blockade of the CD28-B7 pathway, using adenovirus-mediated CTLA4Ig gene transfer, in concert with a low dosage of donor BMCs and SPLCs, may represent a feasible strategy to induce stable mixed chimerism and permit long-term survival of cardiac allografts. [source] Engineering tissues, organs and cellsJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 2 2007Anthony Atala Abstract Patients suffering from diseased and injured organs may be treated with transplanted organs; however, there is a severe shortage of donor organs that is worsening yearly, given the ageing population. In the field of regenerative medicine and tissue engineering, scientists apply the principles of cell transplantation, materials science and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy, including the use of amniotic and placental fetal stem cells. This review covers recent advances that have occurred in regenerative medicine and describes applications of these technologies using chemical compounds that may offer novel therapies for patients with end-stage organ failure. Copyright © 2007 John Wiley & Sons, Ltd. [source] Receptor for Advanced Glycation End Products in Donor Lungs Is Associated with Primary Graft Dysfunction After Lung TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2010A. Pelaez Development of primary graft dysfunction (PGD) is associated with poor outcomes after transplantation. We hypothesized that Receptor for Advanced Glycation End-products (RAGE) levels in donor lungs is associated with the development of PGD. Furthermore, we hypothesized that RAGE levels would be increased with PGD in recipients after transplantation. We measured RAGE in bronchoalveolar lavage fluid (BALf) from 25 donors and 34 recipients. RAGE was also detected in biopsies (transbronchial biopsy) from recipients with and without PGD. RAGE levels were significantly higher in donor lungs that subsequently developed sustained PGD versus transplanted lungs that did not display PGD. Donor RAGE level was a predictor of recipient PGD (odds ratio = 1.768 per 0.25 ng/mL increase in donor RAGE level). In addition, RAGE levels remained high for 14 days in those recipients that developed severe graft dysfunction. Recipients may be at higher risk for developing PGD if they receive transplanted organs that have higher levels of soluble RAGE prior to explantation. Moreover, the clinical and pathologic abnormalities associated with PGD posttransplantation are associated with increased RAGE expression. These findings also raise the possibility that targeting the RAGE signaling pathway could be a novel strategy for treatment and/or prevention of PGD. [source] Organ Donation and Utilization in the United States, 1999,2008AMERICAN JOURNAL OF TRANSPLANTATION, Issue 4p2 2010A. S. Klein Despite the Organ Donation Breakthrough Collaborative's work to engage the transplant community and the suggested positive impact from these efforts, availability of transplanted organs over the past 5 years has declined. Living kidney, liver and lung donations declined from 2004 to 2008. Living liver donors in 2008 dropped to less than 50% of the peak (524) in 2001. There were more living donors that were older and who were unrelated to the recipient. Percentages of living donors from racial minorities remained unchanged over the past 5 years, but percentages of Hispanic/Latino and Asian donors increased, and African American donors decreased. The OPTN/UNOS Living Donor Transplant Committee restructured to enfranchise organ donors and recipients, and to seek their perspectives on living donor transplantation. In 2008, for the first time in OPTN history, deceased donor organs decreased compared to the prior year. Except for lung donors, deceased organ donation fell from 2007 to 2008. Donation after cardiac death (DCD) has accounted for a nearly 10-fold increase in kidney donors from 1999 to 2008. Use of livers from DCD donors declined in 2008 to 2005 levels. Understanding health risks associated with the transplantation of organs from ,high-risk' donors has received increased scrutiny. [source] DonorNet and the Potential Effects on Organ UtilizationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4p2 2010D. A. Gerber The evolution of communication as donor data flows from organ procurement organization to transplant centers has evolved with the incorporation of DonorNet 2007® into the UNetSM system. The ensuing study looks at DonorNet's impact on this process. We established defined time periods for comparison purposes. The study looked at match number for organ placement and overall organ utilization with a focus on ischemia time and graft outcomes. The results of the study demonstrate no significant change in the median match number of organ placement in liver or kidney transplantation. Changes in discard rates were varied amongst transplanted organs and there were noticeable changes in organ sharing with an increase in local allocation for kidney and liver and an ensuing decrease in regional and national distribution. There were no significant differences in the outcomes of livers and kidneys with low offer numbers compared with those with high offer numbers. Overall the study suggests a modest impact by DonorNet on organ placement and utilization, but a longer term study would need to be done to fully evaluate its impact. [source] Epidermal Langerhans Cells Promote Skin Allograft Rejection in Mice With NF-,B-impaired T CellsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 1 2008L. L. Molinero T cells play a major role in the acute rejection of transplanted organs. Using mice transgenic for a T-cell-restricted NF-,B super-repressor (I,B,,N-Tg mice), we have previously shown that T-cell-NF-,B is essential for the acute rejection of cardiac but not skin allografts. In this study, we investigated the mechanism by which skin grafts activate I,B,,N-Tg T cells. Rejection was not due to residual T-cell-NF-,B activity as mice with p50/p52,/, T cells successfully rejected skin grafts. Rather, skin but not cardiac allografts effectively induced proliferation of graft-specific I,B,,N-Tg T cells. Rejection of skin grafts by I,B,,N-Tg mice was in part dependent on the presence of donor Langerhans cells (LC), a type of epidermal dendritic cells (DC), as lack of LC in donor skin grafts resulted in prolongation of skin allograft survival and injection of LC at the time of cardiac transplantation was sufficient to promote cardiac allograft rejection by I,B,,N-Tg mice. Our results suggest that LC allow NF-,B-impaired T cells to reach an activation threshold sufficient for transplant rejection. The combined blockade of T-cell-NF-,B with that of alternative pathways allowing activation of NF-,B-impaired T cells may be an effective strategy for tolerance induction to highly immunogenic organs. [source] Chimerism in Kidneys, Livers and Hearts of Normal Women: Implications for Transplantation StudiesAMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2005Marije Koopmans Tissue chimerism was recently described in transplanted organs from female donors into male recipients, by demonstration of the Y-chromosome in tissue-derived cells. It was claimed that these Y-chromosome positive cells were recipient derived. To find out whether the chimeric cells, derived from pregnancies of sons or blood transfusions, could have been present in the solid organs before transplantation, we performed the following study. In situ hybridization for the Y-chromosome was performed on the normal organs (51 kidneys, 51 livers, 69 hearts) from 75 women of the normal population, whose child and blood transfusion status were known. Chimeric cells were found in 13 kidneys, 10 livers and 4 hearts, of 23 women. There was no relation between the child status or the blood transfusion history with the presence of Y-chromosome positive cells. We have for the first time demonstrated that male cells are present in normal kidneys, livers and hearts. Theoretically, these organs could have been used for the transplantation. Therefore, our findings demonstrate that the chimeric cells thus far described in transplantation studies, are not necessarily donor derived, and could have been present in the organs before the transplantation. [source] | ||||||||||