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Donor Characteristics (donor + characteristic)
Selected AbstractsNon-myeloablative conditioning and allogeneic transplantation for multiple myeloma,AMERICAN JOURNAL OF HEMATOLOGY, Issue 4 2010Keren Osman In multiple myeloma (MM), allogeneic stem cell transplantation (alloHCT) carries a lower relapse risk than autologous transplantation but a greater transplant-related mortality. Nonmyeloablative conditioning for allogeneic transplantation (NST) reduces transplant-related toxicity. Results are encouraging when used during first remission in low-risk patients, but less-so in relapsed or refractory disease. This is a single-center retrospective analysis of 20 previously treated MM patients who underwent NST from matched-related or matched-unrelated donors from 2000,2006. Median age was 52.7 years (37.2,68.0). Twenty-five percent had advanced or high-risk disease. Eleven still had active disease prior to NST. Conditioning was total body irradiation 200 cGy on a single fraction on day ,5, followed by antithymocyte globulin (ATG) 1.5 mg/kg/day and fludarabine 30 mg/m2/day on days ,4 to ,2. All received immunosuppression, most commonly with oral mycofenylate mofetil and cyclosporine beginning on day ,5. At day 100, 50% had achieved complete remission. Transplant-related mortality was 25%. Median overall survival (OS) was 21.2 months (0.6,90+) and progression-free survival (PFS) 6.6 months (0.6,90+). Both OS and PFS were 24% at 3 years. OS was significantly greater for patients with age <52 years (median 27 months vs. 7.9 months, P = 0.031), and there was a trend toward greater OS for those with ,2 microglobulin <2.5 mg/l (median 27 months vs. 7.7 months, P = 0.08). Donor characteristics and Ig type had no significant effect on survival. These data suggest a benefit of NST in relapsed/refractory MM. Randomized trials must be performed to confirm and further qualify this benefit. Am. J. Hematol., 2010. © 2010 Wiley-Liss, Inc. [source] Living Donor and Split-Liver Transplants in Hepatitis C Recipients: Does Liver Regeneration Increase the Risk for Recurrence?AMERICAN JOURNAL OF TRANSPLANTATION, Issue 2 2005Abhinav Humar Concern exists that partial liver transplants (either a living donor [LD] or deceased donor [DD] in hepatitis C virus (HCV)-positive recipients may be associated with an increased risk for recurrence. From 1999 to 2003, at our institution, 51 HCV-positive recipients underwent liver transplants: 32 whole-liver (WL) transplants, 12 LD transplants and 7 DD split transplants. Donor characteristics differed in that WL donors were older, and LD livers had lower ischemic times. Recipient characteristics were similar except that mean MELD scores in LD recipients were lower (p < 0.05). With a mean follow-up of 28.3 months, 46 (90%) recipients are alive: three died from HCV recurrent liver disease and two from tumor recurrence. Based on 1-year protocol biopsies, the incidence of histologic recurrence in the three groups is as follows: WL, 81%; LD, 50% and DD split, 86% (p = 0.06 for LD versus WL). The mean grade of inflammation on the biopsy specimens was: WL, 1.31; LD, 0.33 and DD split, 1.2 (p = 0.002 for LD versus WL; p = 0.03 for LD versus DD split). Mean stage of fibrosis was: WL, 0.96; LD, 0.22 and DD split, 0.60 (p = 0.07 for LD versus WL). Liver regeneration does not seem to affect hepatitis C recurrence as much, perhaps, as factors such as DD status, donor age and cold ischemic time. [source] Expression of p16INK4a in peripheral blood T-cells is a biomarker of human agingAGING CELL, Issue 4 2009Yan Liu Summary Expression of the p16INK4a tumor suppressor sharply increases with age in most mammalian tissues, and contributes to an age-induced functional decline of certain self-renewing compartments. These observations have suggested that p16INK4a expression could be a biomarker of mammalian aging. To translate this notion to human use, we determined p16INK4a expression in cellular fractions of human whole blood, and found highest expression in peripheral blood T-lymphocytes (PBTL). We then measured INK4/ARF transcript expression in PBTL from two independent cohorts of healthy humans (170 donors total), and analyzed their relationship with donor characteristics. Expression of p16INK4a, but not other INK4/ARF transcripts, appeared to exponentially increase with donor chronologic age. Importantly, p16INK4a expression did not independently correlate with gender or body-mass index, but was significantly associated with tobacco use and physical inactivity. In addition, p16INK4a expression was associated with plasma interleukin-6 concentration, a marker of human frailty. These data suggest that p16INK4a expression in PBTL is an easily measured, peripheral blood biomarker of molecular age. [source] The biopsied donor liver: Incorporating macrosteatosis into high-risk donor assessment,LIVER TRANSPLANTATION, Issue 7 2010Austin L. Spitzer To expand the donor liver pool, ways are sought to better define the limits of marginally transplantable organs. The Donor Risk Index (DRI) lists 7 donor characteristics, together with cold ischemia time and location of the donor, as risk factors for graft failure. We hypothesized that donor hepatic steatosis is an additional independent risk factor. We analyzed the Scientific Registry of Transplant Recipients for all adult liver transplants performed from October 1, 2003, through February 6, 2008, with grafts from deceased donors to identify donor characteristics and procurement logistics parameters predictive of decreased graft survival. A proportional hazard model of donor variables, including percent steatosis from higher-risk donors, was created with graft survival as the primary outcome. Of 21,777 transplants, 5051 donors had percent macrovesicular steatosis recorded on donor liver biopsy. Compared to the 16,726 donors with no recorded liver biopsy, the donors with biopsied livers had a higher DRI, were older and more obese, and a higher percentage died from anoxia or stroke than from head trauma. The donors whose livers were biopsied became our study group. Factors most strongly associated with graft failure at 1 year after transplantation with livers from this high-risk donor group were donor age, donor liver macrovesicular steatosis, cold ischemia time, and donation after cardiac death status. In conclusion, in a high-risk donor group, macrovesicular steatosis is an independent risk factor for graft survival, along with other factors of the DRI including donor age, donor race, donation after cardiac death status, and cold ischemia time. Liver Transpl 16:874,884, 2010. © 2010 AASLD. [source] Does middle hepatic vein omission in a right split graft affect the outcome of liver transplantation?LIVER TRANSPLANTATION, Issue 6 2007A comparative study of right split livers with, without the middle hepatic vein Preservation of the middle hepatic vein (MHV) for a right split liver transplantation (SLT) in an adult recipient is still controversial. The aim of this study was to evaluate the graft and patient outcomes after liver transplantation (LT) using a right split graft, according to the type of venous drainage. From February 2000 to May 2006, 33 patients received 34 cadaveric right split liver grafts. According to the type of recipient pairs (adult/adult or adult/child), the right liver graft was deprived of the MHV or not. The first group (GI, n = 15) included grafts with only the right hepatic vein (RHV) outflow, the second (GII, n = 18) included grafts with both right and MHV outflows. The 2 groups were similar for patient demographics, initial liver disease, and donor characteristics. In GI and GII, graft-to-recipient-weight ratio (GRWR) was 1.2 ± 0% and 1.6 ± 0.3% (P < 0.05), and cold ischemia time was 10 hours 55 minutes ± 2 hours 49 minutes and 10 hours 47 minutes ± 3 hours 32 minutes, respectively (P = not significant). Postoperative death occurred in 1 patient in each group. Vascular complications included anastomotic strictures: 2 portal vein (PV), 1 hepatic artery (HA), and 1 RHV anastomotic strictures; all in GI. Biliary complications occurred in 20% and 22% of the patients, in GI and GII, respectively (P = not significant). There were no differences between both groups regarding postoperative outcome and blood tests at day 1-15 except for a significantly higher cholestasis in GI. At 1 and 3 yr, patient survival was 94% for both groups and graft survival was 93% for GI and 90% for GII (P = not significant). In conclusion, our results suggest that adult right SLT without the MHV is safe and associated with similar long-term results as compared with those of the right graft including the MHV, despite that early liver function recovered more slowly. Technical refinements in outflow drainage should be evaluated in selected cases. Liver Transpl 13:829,837, 2007. © 2007 AASLD. [source] Fever, mental impairment, acute anemia, and renal failure in patient undergoing orthotopic liver transplantation: Posttransplantation malariaLIVER TRANSPLANTATION, Issue 4 2006Francesco Menichetti A case of post-transplant malaria is described. The patient presented fever and severe anemia after orthotopic liver transplantation. Diagnosis was made only after the review of donor characteristics. Although a high parasitemia was found at the moment of diagnosis, the treatment with quinine and doxycycline was successful. Donor epidemiology should always be considered for a prompt diagnosis of rare tropical diseases in the graft recipients. Liver Transpl 12:674,676, 2006. © 2006 AASLD. [source] Change in live donor characteristics over the last 25 years: A single centre experienceNEPHROLOGY, Issue 7 2008MOHD O KAISAR SUMMARY: Aim: While deceased donor kidney transplantation rates have remained stagnant, live donor kidney transplantation (LDKT) rates have increased significantly over the last decade, and are now a major component of renal transplantation programmes worldwide. Additionally, there has been an increased utilization of more marginal donors, including donors who are obese, older and subjects with well-controlled hypertension. Method: A retrospective audit of all live donors at the Princess Alexandra Hospital Renal Transplantation unit was performed from 24 August 1982 to 29 May 2007 to assess any change in donor characteristics over time. Results: There were 373 live donor operations. Over the last 25 years there has been a significant increase in the number of donors who are either older or obese. Furthermore, there is a greater proportion of spousal and emotionally related LDKT. Conclusion: It is imperative that donors, in particular marginal donors, are followed up long-term to determine their risk of kidney and cardiovascular disease and initiation of appropriate treatment if required. [source] Pediatric cardiothoracic domino transplantation: The psychological costs and benefitsPEDIATRIC TRANSPLANTATION, Issue 5 2004Jo Wray Abstract:, The first domino transplants were carried out in the UK in 1987, since which time 52 such procedures have been carried out involving patients within the paediatric cardiothoracic transplant programmes of Harefield and Great Ormond Street Hospitals. Although there are medical advantages in using domino organs , such as the ability for preoperative cross-matching, the heart not being subjected to the biochemical changes of brain death and less post-transplant coronary artery disease in the recipients of domino hearts compared with the recipients of hearts from cadaveric donors , the psychological sequelae for both donor and recipient have not been previously studied. The objective of this study was to identify the main psychological themes for patients involved in the domino programmes at the two hospitals, focusing on those situations where both patients were cared for in the same tertiary centre. Patients and their families were interviewed during routine outpatient clinic visits. Negative themes identified by patients included anxiety, guilt, resentment and anger if either patient had a poor outcome or suffered significant complications, disappointment and low self-esteem for potential donors whose heart was not used and recipient awareness of donor characteristics. Positive themes included gratefulness, comfort for the recipient that someone had not had to die for them directly and the benefit to the donor of giving their heart to another patient. In conclusion, domino transplantation has many medical advantages but there are significant negative psychological concomitants which need to be addressed within the multi-disciplinary management of these patients. [source] Increasing Lung Allocation Scores Predict Worsened Survival Among Lung Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2010V. Liu Implemented in 2005, the lung allocation score (LAS) aims to distribute donor organs based on overall survival benefits for all potential recipients, rather than on waiting list time accrued. While prior work has shown that patients with scores greater than 46 are at increased risk of death, it is not known whether that risk is equivalent among such patients when stratified by LAS score and diagnosis. We retrospectively evaluated 5331 adult lung transplant recipients from May 2005 to February 2009 to determine the association of LAS (groups based on scores of ,46, 47,59, 60,79 and ,80) and posttransplant survival. When compared with patients with LAS , 46, only those with LAS , 60 had an increased risk of death (LAS 60,79: hazard ratio [HR], 1.52; 95% confidence interval [CI], 1.21,1.90; LAS , 80: HR, 2.03; CI, 1.61,2.55; p < 0.001) despite shorter median waiting list times. This risk persisted after adjusting for age, diagnosis, transplant center volume and donor characteristics. By specific diagnosis, an increased hazard was observed in patients with COPD with LAS , 80, as well as those with IPF with LAS , 60. [source] ASTS Recommended Practice Guidelines for Controlled Donation after Cardiac Death Organ Procurement and TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2009D. J. Reich The American Society of Transplant Surgeons (ASTS) champions efforts to increase organ donation. Controlled donation after cardiac death (DCD) offers the family and the patient with a hopeless prognosis the option to donate when brain death criteria will not be met. Although DCD is increasing, this endeavor is still in the midst of development. DCD protocols, recovery techniques and organ acceptance criteria vary among organ procurement organizations and transplant centers. Growing enthusiasm for DCD has been tempered by the decreased yield of transplantable organs and less favorable posttransplant outcomes compared with donation after brain death. Logistics and ethics relevant to DCD engender discussion and debate among lay and medical communities. Regulatory oversight of the mandate to increase DCD and a recent lawsuit involving professional behavior during an attempted DCD have fueled scrutiny of this activity. Within this setting, the ASTS Council sought best-practice guidelines for controlled DCD organ donation and transplantation. The proposed guidelines are evidence based when possible. They cover many aspects of DCD kidney, liver and pancreas transplantation, including donor characteristics, consent, withdrawal of ventilatory support, operative technique, ischemia times, machine perfusion, recipient considerations and biliary issues. DCD organ transplantation involves unique challenges that these recommendations seek to address. [source] Moving Kidney Allocation Forward: The ASTS PerspectiveAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2009R. B. Freeman In 2008, the United Network for Organ Sharing issued a request for information regarding a proposed revision to kidney allocation policy. This plan described combining dialysis time, donor characteristics and the estimated life years from transplant (LYFT) each candidate would gain in an allocation score that would rank waiting candidates. Though there were some advantages of this plan, the inclusion of LYFT raised many questions. Foremost, there was no clear agreement that LYFT should be the main criterion by which patients should be ranked. Moreover, to rank waiting candidates with this metric, long-term survival models were required in which there was no incorporation of patient preference or discounting for long survival times and for which the predictive accuracy did not achieve accepted standards. The American Society of Transplant Surgeons was pleased to participate in the evaluation of the proposal. Ultimately, the membership did not favor this proposal, because we felt that it was too complicated and that the projected slight increase in overall utility was not justified by the compromise in individual justice that was required. We offer alternative policy options to address some of the unmet needs and issues that were brought to light during this interesting process. [source] Recipient Outcomes for Expanded Criteria Living Kidney Donors: The Disconnect Between Current Evidence and PracticeAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2009Y. Iordanous Older individuals or those with medical complexities are undergoing living donor nephrectomy more than ever before. Transplant outcomes for recipients of kidneys from these living expanded criteria donors are largely uncertain. We systematically reviewed studies from 1980 to June 2008 that described transplant outcomes for recipients of kidneys from expanded criteria living donors. Results were organized by the following criteria: older age, obesity, hypertension, reduced glomerular filtration rate (GFR), proteinuria and hematuria. Pairs of reviewers independently evaluated each citation and abstracted data on study and donor characteristics, recipient survival, graft survival, serum creatinine and GFR. Transplant outcomes for recipients of kidneys from older donors (,60 years) were described in 31 studies. Recipients of kidneys from older donors had poorer 5-year patient and graft survival than recipients of kidneys from younger donors [meta-analysis of 12 studies, 72% vs. 80%, unadjusted relative risk (RR) of survival 0.89, 95% confidence interval (CI) 0.83,0.95]. In meta-regression, this association diminished over time (1980s RR 0.79, 95% CI 0.65,0.96 vs. 1990s RR 0.91, 95% CI 0.85,0.99). Few transplant outcomes were described for other expanded criteria. This disconnect between donor selection and a lack of knowledge of recipient outcomes should give transplant decision-makers pause and sets an agenda for future research. [source] Survival Benefit-Based Deceased-Donor Liver AllocationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4p2 2009D. E. Schaubel Currently, patients awaiting deceased-donor liver transplantation are prioritized by medical urgency. Specifically, wait-listed chronic liver failure patients are sequenced in decreasing order of Model for End-stage Liver Disease (MELD) score. To maximize lifetime gained through liver transplantation, posttransplant survival should be considered in prioritizing liver waiting list candidates. We evaluate a survival benefit based system for allocating deceased-donor livers to chronic liver failure patients. Under the proposed system, at the time of offer, the transplant survival benefit score would be computed for each patient active on the waiting list. The proposed score is based on the difference in 5-year mean lifetime (with vs. without a liver transplant) and accounts for patient and donor characteristics. The rank correlation between benefit score and MELD score is 0.67. There is great overlap in the distribution of benefit scores across MELD categories, since waiting list mortality is significantly affected by several factors. Simulation results indicate that over 2000 life-years would be saved per year if benefit-based allocation was implemented. The shortage of donor livers increases the need to maximize the life-saving capacity of procured livers. Allocation of deceased-donor livers to chronic liver failure patients would be improved by prioritizing patients by transplant survival benefit. [source] Improving Outcomes of Liver Retransplantation: An Analysis of Trends and the Impact of Hepatitis C InfectionAMERICAN JOURNAL OF TRANSPLANTATION, Issue 2 2008M. Ghabril Retransplantation (RT) in Hepatitis C (HCV) patients remains controversial. Aims: To study trends in RT and evaluate the impact of HCV status in the context of a comprehensive recipient and donor risk assessment. The UNOS database between 1994 and October 2005 was utilized to analyze 46 982 LT and RT. Graft and patient survival along with patient and donor characteristics were compared for 2283 RT performed in HCV and non-HCV patients during 1994,1997, 1998,2001 and 2002,October 2005. Overall HCV prevalence at RT increased from 36% in the initial period to 40.6% after 2002. In our study group, 1-year patient and graft survival post-RT improved over the same time intervals from 65.0% to 70.7% and 54.87% to 65.8%, respectively. HCV was only associated with decreased patient and graft survival with a retransplant (LT-RT) interval (RI) >90 days. Independent predictors of mortality for RT with RI >90 days were patient age, MELD score >25, RI <1 year, warm ischemia time ,75 min and donor age ,60 (significant for HCV patients only). Outcomes of RT are improving, but can be optimized by weighing recipient factors, anticipation of operative factors and donor selection. [source] Thymoglobulin-Associated Cd4+ T-Cell Depletion and Infection Risk in HIV-Infected Renal Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2006J.T. Carter HIV-infected patients are increasingly referred for kidney transplantation, and may be at an increased risk for rejection. Treatment for rejection frequently includes thymoglobulin. We studied thymoglobulin's effect on CD4+ T-cell count, risk of infection and rejection reversal in 20 consecutive HIV-infected kidney recipients. All patients used antiretroviral therapy and opportunistic infection prophylaxis. Maintenance immunosuppression consisted of prednisone, mycophenolate mofetil and cyclosporine. Eleven patients received thymoglobulin (7 for rejection and 4 for delayed/slow graft function) while 9 did not. These two groups were similar in age, gender, race, donor characteristics and immunosuppression. Mean CD4+ T-cell counts remained stable in patients who did not receive thymoglobulin, but became profoundly suppressed in those who did, decreasing from 475 ± 192 to 9 ± 10 cells/,L (p < 0.001). Recovery time ranged from 3 weeks to 2 years despite effective HIV suppression. Although opportunistic infections were successfully suppressed, low CD4+ T-cell count was associated with increased risk of serious infections requiring hospitalization. Rejection reversed in 6 of 7 patients receiving thymoglobulin. We conclude that thymoglobulin reverses acute rejection in HIV-infected kidney recipients, but produces profound and long-lasting suppression of the CD4+ T-cell count associated with increased risk of infections requiring hospitalization. [source] The Broad Spectrum of Quality in Deceased Donor KidneysAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2005Jesse D. Schold The quality of the deceased donor organ clearly is one of the most crucial factors in determining graft survival and function in recipients of a kidney transplant. There has been considerable effort made towards evaluating these organs culminating in an amendment to allocation policy with the introduction of the expanded criteria donor (ECD) policy. Our study, from first solitary adult deceased donor transplant recipients from 1996 to 2002 in the National Scientific Transplant Registry database, presents a donor kidney risk grade based on significant donor characteristics, donor,recipient matches and cold ischemia time, generated directly from their risk for graft loss. We investigated the impact of our donor risk grade in a naïve cohort on short- and long-term graft survival, as well as in subgroups of the population. The projected half-lives for overall graft survival in recipients by donor risk grade were I (10.7 years), II (10.0 years), III (7.9 years), IV (5.7 years) and V (4.5 years). This study indicates that there is great variability in the quality of deceased donor kidneys and that the assessment of risk might be enhanced by this scoring system as compared to the simple two-tiered system of the current ECD classification. [source] Effect of donor characteristics, technique of harvesting and in vitro processing on culturing of human marrow stroma cells for tissue engineered growth of boneCLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2005Helge Bertram Abstract: The aim of this study was to assess the effect of donor characteristics and the technique of harvesting and in vitro processing on the efficacy of culturing of human mesenchymal stem cells (hMSCs) for tissue engineered growth of bone. Cultures of hMSCs were derived from iliac crest bone marrow aspirates (21 donors, age 11,76) and from cancellous bone grafting material (32 donors, age 13,84). Age had no significant effect on the ability to isolate and culture hMSCs, although the failure rate was 55.6% in donors beyond the age of 60, while it varied between 14.3% and 22.2% in donors under 60 years of age. Male and female donors had comparable failure rates (27.3% and 28.6%, respectively). Culturing of hMSCs was successful in 90.4% of marrow aspirates from 21 donors and in 62.5% of cancellous bone specimens from 35 donors. This difference was statistically significant (P=0.023). Regression analysis confirmed that at simultaneous testing of the three variables, only the source of cells significantly affected the result (P=0.043). Morphological evaluation of the unfractionated primary population showed a change in cell shape of the adherent cells from a triangular into thin spindle-shaped elongated form, which remains until confluence. When the cultures were exposed to osteoinductive medium, various morphotypes expressing different levels of alkaline phosphatase and secreting different amounts of mineral were evident. Morphology of marrow stroma cells (MSCs) from marrow aspirates was not different from MSCs derived from cancellous bone specimens. Expression of osteogenic markers in MSCs as shown by PCR as well, did not differ between the two sources. It is concluded that marrow aspirates and cancellous bone specimens produce comparable populations of MSCs. However, bone marrow aspirates from donors under the age of 60 years rather than cancellous bone chips are favourable for isolation and expansion of hMSCs for tissue engineered growth of bone. Résumé Le but de cette étude a été d'analyser l'effet des caractéristiques du donneur et la technique de prélèvement et du processus in vitro sur l'efficacité des cultures des cellules souches mésenchymateuses humaines (hMSC) pour la croissance tissulaire en laboratoire de l'os. Les cultures de hMSC provenaient de la moelle osseuse de la crête iliaque (21 donneurs de 11 à 76 ans) et de matériel de greffe osseuse d'os spongieux (32 donneurs de 13 à 84 ans). L'âge n'avait aucun effet significatif sur l'habilitéà isoler et à mettre en culture les hMSC bien que le taux d'échec était de 56% chez les donneurs au-dessus de 60 ans et variait de 14 à 22% chez les donneurs en-dessous de 60 ans. Les hommes et les femmes avaient des taux d'échec comparables de respectivement 27 et 28%. La mise en culture des hMSC a réussi dans 90% des prélèvements de moelle et dans 63% dans les échantillons osseux spongieux. Cette différence était statistiquement significative (P=0,023). L'analyse de régression a confirmé qu'avec un test simultané des trois variables, seul la source de cellules avait un réel effet sur le résultat (P=0,043). L'évaluation morphologique de la population primaire non-fractionnée a montré un changement dans l'apparence des cellules adhérentes depuis un aspect triangulaire à une forme allongée en forme de fuseau qui restait jusqu'à confluence. Lorsque les cultures étaient exposées à un milieu ostéoinductif différents morphotypes exprimant différents niveaux de phosphatase alcaline et secrétant différentes quantitées de minéraux étaient mis en évidence. La morphologie des MSC des prélèvements de la moelle n'était pas différente des MSC provenant des spécimens osseux spongieux. L'expression des marqueurs ostéogéniques dans les MSC ne montrait par PCR aucune différence entre ces deux sources. Les prélèvements de moelle et les spécimens osseux spongieux produisent donc des populations comparables de MSC. Cependant, les aspirations de moelle de donneurs en-dessous de 60 ans plutôt que les chips osseux spongieux sont favorables pour l'isolation et l'expansion des hMSC pour la croissance osseuse en laboratoire. Zusammenfassung Es war das Ziel dieser Studie, den Einfluss von Spender-Merkmalen, Entnahmetechnik und in vitro -Behandlung bei der erfolgreichen Kultivierung von menschlichen mesenchymalen Stammzellen (hMSCs) für das gewebsgesteuerte Knochenwachstum zu untersuchen. Die Kulturen der hMSCs gewann man aus vom Beckenkamm aspiriertem Knochenmark (21 Spender, Alter 11,76) und von Spongiosa aus Spendermaterial (32 Spender, Alter 13,84). Das Alter hatte keinen signifikanten Einfluss auf die erfolgreiche Isolierung und Kultivierung von hMSCs, obgleich die Misserfolgsrate bei Spendern über 60 Jahren 55.6% betrug, währenddem sie bei Spendern unter 60 Jahren zwischen 14.3% und 22.2% variierte. Männer und Frauen hatten vergleichbare Misserfolgsraten (27.3%, beziehungsweise 28.6%). Die Kultivierung von hMSCs war bei 90.4% des aspirierten Marks von 21 Spendern und 62.5% der Spongiosa von 35 Spendern erfolgreich. Diese Differenz war statistisch signifikant (P=0.023). Die Regressionsanalyse bestätigte, dass von den drei gleichzeitig getesteten Variablen nur die Entnahmequelle der Zellen das Resultat signifikant beeinflusste (P=0.043). Die morphologische Untersuchung der unfraktionierten Primärpopulation zeigte bei den adhärenten Zellen eine Veränderung der Zellform von einer dreieckigen zu einer spindelförmigen länglichen Form. Diese blieb bis zu ihrem Zusammenwachsen erhalten. Wurden die Kulturen einem osteoinduktiven Einfluss ausgesetzt, entwickelten sich verschiedene Morphotypen, die auch verschiedene Mengen alkalischer Phosphatase und Mineralien ausschieden. Die Morphologie der MSCs aus dem aspirierten Knochenmark war nicht anders als diejenige von MSCs aus spongiösen Knochenproben. Die Ausscheidung von osteogenen Markern durch die MSCs, auch messbar durch den PCR, verhielt sich bei den Zellen aus beiden Quellen gleich. Man schloss daher, dass aspiriertes Knochenmark und Spongiosa vergleichbare Populationen von MSCs produzieren. Für die Isolation und Expansion von hMSCs zur gesteuerten Knochengewebsregeneration ist aspiriertes Knochenmark vorteilhafter als spongiöse Knochenchips und der Spendern ist von Vorteil jünger als 60 Jahre. Resumen La intención de este estudio fue valorar el efecto de las características del donante y de la técnica de recogida y del procesamiento in vivo sobre la eficacia del cultivo de células madre mesenquimales humanas (hMSCs) para crecimiento óseo por ingeniería tisular. Los cultivos de hMSCs se derivaron de aspirados de la médula ósea de la cresta iliaca (21 donantes, edad 11,76) y de material de injerto de hueso esponjoso (32 donantes, edad 13,84). La edad no tuvo un efecto significativo en la habilidad para aislar y cultivar hMSCs, aunque el índice de fracaso fue del 55.6% en donantes por encima de los 60 años, mientras que varió entre el 14.3% y el 22.2% en donantes por debajo de los 60 años. Los donantes varones y hembras tuvieron índices de fracaso comparables (27.3 y 28.6%, respectivamente). El cultivo de hMSCs tuvo éxito en el 90.4% de los aspirados medulares de 21 donantes y en 62.5% de los especímenes de hueso esponjoso de 35 donantes. Esta diferencia fue estadísticamente significativa (P=0.023). El análisis de regresión confirmó que en la prueba simultanea de las tres variables, solo el origen de las células afectó significativamente el resultado (P=0.043). La evaluación morfológica de la población primaria no fraccionada mostró un cambio en la forma celular de las células adherentes de triangular a una forma de huso fino elongado, que se mantiene hasta su confluencia. Cuando los cultivos se expusieron a un medio osteoconductivo se evidenciaron varios morfotipos manifestando diferentes niveles de fosfatasa alcalina y segregando diferentes cantidades de mineral. La morfología de las MSCs de los aspirados medulares no fue diferente de las MSCs derivadas de los especímenes de hueso esponjoso. La manifestación de marcadores osteogénicos en MSCs mostrado por PCR tampoco difirió entre las dos fuentes. Se concluye que los aspirados medulares y los especímenes de hueso esponjoso producen poblaciones comparables de MSCs. De todos modos, los aspirados de médula ósea de donantes menores de 60 años por encima de las virutas de hueso esponjoso son más favorables para el aislamiento y la expansión de hMSCs para crecimiento óseo por ingeniería tisular. [source] Liver transplantation in patients aged 65 and over: a case,control studyCLINICAL TRANSPLANTATION, Issue 5 2010R. Montalti Montalti R, Rompianesi G, Di Benedetto F, Ballarin R, Gerring RC, Busani S, De Pietri L, De Ruvo N, Iemmolo RM, Guerrini GP, Smerieri N, Gerunda GE. Liver transplantation in patients aged 65 and over: a case,control study. Clin Transplant 2010 DOI: 10.1111/j.1399-0012.2010.01230.x. © 2010 John Wiley & Sons A/S. Abstract:, Introduction:, The average age of patients undergoing liver transplantation (LT) is consistently increasing. The aim of this case,control study is to evaluate survival and outcome of patients ,65 yr compared to younger patients undergoing LT. Materials and methods:, From 10/00 to 4/08 we performed 330 primary LT, 31 (9.4%) of these were in patients aged 65,70. Following a case,control approach, we compared these patients with 31 patients aged between 41 and 64 yr and matched according to sex, LT indication, viral status, cadaveric/living donor, LT timing, and Model for End-Stage Liver Disease (MELD) score. Results:, There were no statistically significant differences in demographic and surgical donor characteristics. The mean MELD score was under 18 in both groups. Post-LT complications occurred with a similar incidence in the two groups. one-, three-, and five-yr survival was 83.9%, 80.6%, and 80.6%, respectively, for the elderly group, and 80.6%, 73.8%, and 73.8%, respectively, for the young group (p = 0.61). Discussion:, Patients aged between 65 and 70 with low MELD score who undergo LT have the same short- and middle-term survival expectancy, morbidity, and outcome quality as younger patients with the same indication and same pre-LT pathology severity, whatever they might be. Thus, chronological age alone should not deter LT workup in patients >65 and <70. [source] Thoracic organ donor characteristics associated with successful lung procurementCLINICAL TRANSPLANTATION, Issue 1 2001Doff B McElhinney Purpose: A shortage of suitable donors is the major impediment to clinical lung transplantation. The rate of lung recovery from potential donors is lower than that for other organs. The purpose of this study was to evaluate what factors could be modified to improve the rate of cadaver lung recovery. Methods: We performed a retrospective review of records from all thoracic organ donors procured by the California Transplant Donor Network between 1 January 1995 and 31 May 1997 (251 donors) to determine which donor management factors were associated with an increased likelihood of successful lung procurement. Results: There were 88 lung donors (L) and 163 donors from which hearts but no lungs were procured (H). Longer time to donor network referral was associated with a reduced chance for successful lung procurement. Donor age, cause of death, and time of admission were not important factors. Most donors in this study had an acceptable A-a gradient at admission to the hospital but lung function deteriorated in group H. Corticosteroid usage and initially clear breath sounds were independent predictors of successful procurement by multivariate analysis. Conclusions: Early contact with the donor referral network, and corticosteroids may help to improve the lung procurement rate from potential donors. [source] | ||||||||||