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1.
Liver transplantation allows to treat patients with end-stage cirrhosis as well as some liver malignancies (small size hepatocellular carcinoma) with a life expectancy exceeding 70 and 60 % at 5 years, respectively. Current immunosuppressive agents make it possible to prevent chronic rejection in more than 90 % of the patients and to preserve an excellent quality of life in most cases. The principal limiting factor for liver transplantation is represented by the scarcity of brain-dead donors. Indeed, despite the selection of those candidates who have the best chance of surviving after transplantation, several months are usually necessary for obtaining a graft and the mortality on the waiting list may reach 10 to 15 %. Organ shortage incited to develop alternatives to conventional transplantation, the most important of which are living donor transplantation and split liver transplantation. Living donor transplantation can be applied to about 20 to 30 % of candidates. Thought initially smaller, the partial graft regenerates and its volume is restored within a few weeks. The results of living donor transplantation in terms of survival are comparable to those of cadaveric transplantation. The risk for the donor has to be lower than 1 % which makes that selection must be especially cautious. Donors must be direct relatives or spouses. Split liver transplantation technique, based on the separation of a cadaveric graft into two functional parts transplanted in two distinct recipients, although attractive, is applicable to less than 25 % of the donors. Education for organ donation in the general population still remains a priority.  相似文献   

2.
Objectives: To compare the priorities of the general public, family doctors, and gastroenterologists in allocating donor livers to potential recipients of liver allograft. Design: Representative quota sampling of 1000 members of the general public and 200 family doctors, and a postal questionnaire of 100 gastroenterologists. Subjects: Respondents were given eight hypothetical case histories (based on real patients) and asked to select recipients for four donor livers. Cases were selected to identify controversial areas such as extremes of age, misuse of alcohol, and intravenous drugs. Respondents were also asked to select the least deserving case and which of seven possible factors (time on waiting list, outcome, age, value to society, return to work, previous use of illicit drugs, and involvement of alcohol in the liver damage) should be used to select patients already listed for transplantation. Focus groups were also held to explore further the reasons for the choices given. Results: There were considerable differences between the three groups in the choice of the recipients, although alcohol use and antisocial behaviour always rated low. For selection of recipients the general public thought that, in decreasing order of importance, age, outcome, and time on the waiting list were the most important factors in selecting recipients; family doctors rated outcome, age, and likely work status after transplantation and the gastroenterologists outcome, work status, and non-involvement of alcohol in the cause of the liver disease as the most important factors. Conclusions: The views of the public are at variance with those of clinicians. Further debate is required to ensure an equitable and appropriate distribution of a scarce resource.

Key messages

  • The shortage of donor livers means that rationing of the scarce resource is required
  • The priorities of the public differ from those of the medical profession
  • The public tend to prioritise on a more emotional basis and rank those with antisocial behaviour lowest
  • There needs to be more discussion and agreement about the priorities for allocation of scarce resources
  相似文献   

3.
With over 110,000 patients waiting for organ transplantation, the current crisis in organ transplantation is based on a lack of donors after brain-death (DBD). A very large alternative pool of donor organs that remain untapped are the donors after cardiac death (DCD), recovered after cardiac activity has ceased and therefore sustained some ischemic injury. Machine perfusion has been proposed as a novel modality of organ preservation and treatment to render such cadaveric organs, and in particular livers, transplantable. Two key issues that remain unaddressed are how to assess whether a DCD liver is damaged beyond repair, and whether machine perfusion has rendered an injured organ sufficiently viable for transplantation. In this work, we present a metabolic analysis of the transient responses of cadaveric rat livers during normothermic machine perfusion (NMP), and develop an index of ischemia that enables evaluation of the organ ischemic injury level. Further, we perform a discriminant analysis to construct a classification algorithm with >0.98 specificity to identify whether a given perfused liver is ischemic or fresh, in effect a precursor for an index of transplantability and a basis for the use of statistical process control measures for automated feedback control of treatment of ischemic injury in DCD livers. The analyses yield an index based on squared prediction error (SPE) as log(SPE) >1.35 indicating ischemia. The differences between metabolic functions of fresh and ischemic livers during perfusion are outlined and the metabolites that varied significantly for ischemic livers are identified as ornithine, arginine, albumin and tyrosine.  相似文献   

4.
M Carrier  R Cartier  L C Pelletier 《CMAJ》1994,150(9):1443-1448
OBJECTIVES: To evaluate the demand for organs for transplantation and to recommend a reorganization of transplantation services in Quebec. DESIGN: Retrospective study. SETTING: Province of Quebec, 1988 to 1992. PATIENTS: All patients on waiting lists for organ transplantation and patients who received transplants registered in national data banks. MAIN OUTCOME MEASURES: The actual annual demand for organ transplantation and the rate of transplantations performed. RESULTS: The rates of heart transplantation were lower than the actual annual demand, which resulted in many patients dying while awaiting transplantation. The actual annual demand for heart transplantation decreased during the last 5 years from 10.9 per million people in 1987 to 6.7 in 1992. The rates of heart transplantation in Quebec were higher than the Canadian average. The actual demand for lung transplantation was only 2.9 per million people on average in 1992. Demand for liver transplantation increased annually, reaching 8.6 per million in 1992. The rate of transplantation increased likewise but remained insufficient. The demand for kidney transplantation reached 27.2 per million people in 1992, and the transplantation rate was 17.8. CONCLUSIONS: Taking into account the actual demand for and supply of organ transplantation, to insure high-quality service and to control costs associated with organ transplantation, we recommend that the present system in Quebec be reorganized so that transplantations are performed in 12 centres: 7 for kidney transplantation, 2 for hearts, 2 for livers and 1 for lungs.  相似文献   

5.
The success of liver transplantation has resulted in a dramatic organ shortage. In most transplant regions 20-30% of patients on the waiting list for liver transplantation die without receiving an organ transplant or are delisted for disease progression. One strategy to increase the donor pool is the utilization of marginal grafts, such as fatty livers, grafts from older donors, or donation after cardiac death (DCD). The current preservation technique of cold static storage is only poorly tolerated by marginal livers resulting in significant organ damage. In addition, cold static organ storage does not allow graft assessment or repair prior to transplantation.These shortcomings of cold static preservation have triggered an interest in warm perfused organ preservation to reduce cold ischemic injury, assess liver grafts during preservation, and explore the opportunity to repair marginal livers prior to transplantation. The optimal pressure and flow conditions, perfusion temperature, composition of the perfusion solution and the need for an oxygen carrier has been controversial in the past.In spite of promising results in several animal studies, the complexity and the costs have prevented a broader clinical application so far. Recently, with enhanced technology and a better understanding of liver physiology during ex vivo perfusion the outcome of warm liver perfusion has improved and consistently good results can be achieved.This paper will provide information about liver retrieval, storage techniques, and isolated liver perfusion in pigs. We will illustrate a) the requirements to ensure sufficient oxygen supply to the organ, b) technical considerations about the perfusion machine and the perfusion solution, and c) biochemical aspects of isolated organs.  相似文献   

6.
Objective To examine the access to the renal transplant waiting list and renal transplantation in Scotland.Design Cohort study.Setting Renal and transplant units in Scotland.Participants 4523 adults starting renal replacement therapy in Scotland between 1 January 1989 and 31 December 1999.Main outcome measures Impact of age, sex, social deprivation, primary renal disease, renal or transplant unit, and geography on access to the waiting list and renal transplantation.Results 1736 of 4523 (38.4%) patients were placed on the waiting list for renal transplantation and 1095 (24.2%) underwent transplantation up to 31 December 2000, the end of the study period. Patients were less likely to be placed on the list if they were female, older, had diabetes, were in a high deprivation category, and were treated in a renal unit in a hospital with no transplant unit. Patients living furthest away from the transplant centre were listed more quickly. The only factors governing access to transplantation once on the list were age, primary renal disease, and year of listing. A significant centre effect was found in access to the waiting list and renal transplantation.Conclusions A major disparity exists in access to the renal transplant waiting list and renal transplantation in Scotland. Comorbidity may be an important factor.  相似文献   

7.
In a Living Donor List Exchange program, the donor makes his kidney available for allocation to patients on the postmortal waiting‐list and receives in exchange a postmortal kidney, usually an O‐kidney, to be given to the recipient he favours. The program can be a solution for a candidate donor who is unable to donate directly or to participate in a paired kidney exchange because of blood group incompatibility or a positive cross‐match. Each donation within an LDLE program makes an additional organ available for transplantation. But because most of the pairs making use of the program will be A/O incompatible, it will also tend to increase the waiting time for patients with blood group O, who already have the longest waiting time. It has therefore been objected that the program is materially unjust, because it further disadvantages the least advantaged. This objection appeals to John Rawls’ difference principle. However, the context for which Rawls proposed that difference principle, is significantly different from the present one. Applying the principle here amounts to a lop‐sided trade‐off between considerations of need and considerations of overall utility. Considerations of formal justice, however, may lead to a stronger objection to LDLE programs. Such a program means that one O‐patient on the waiting list is exempted from the application of the general criteria used in constructing the list because he has a special bargaining advantage. This objection is spelled out and weighed against the obvious attraction of LDLE in a situation of (extreme) organ scarcity.  相似文献   

8.
Type 1 diabetes (T1D) is caused by autoimmune disease that leads to the destruction of pancreatic β-cells. Transplantation of cadaveric pancreatic organs or pancreatic islets can restore normal physiology. However, there is a chronic shortage of cadaveric organs, limiting the treatment of the majority of patients on the pancreas transplantation waiting list. Here, we hypothesized that human iPS cells can be directly differentiated into insulin producing cells (IPCs) capable of secreting insulin. Using a series of pancreatic growth factors, we successfully generated iPS cells derived IPCs. Furthermore, to investigate the capability of these cells to secrete insulin in vivo, the differentiated cells were transplanted under the kidney capsules of diabetic immunodeficient mice. Serum glucose levels gradually declined to either normal or near normal levels over 150 days, suggesting that the IPCs were secreting insulin. In addition, using MRI, a 3D organoid appeared as a white patch on the transplanted kidneys but not on the control kidneys. These organoids showed neo-vascularization and stained positive for insulin and glucagon. All together, these data show that a pancreatic organ can be created in vivo providing evidence that iPS cells might be a novel option for the treatment of T1D.  相似文献   

9.

Background

Advanced liver cirrhosis is associated with systemic hemodynamic derangement leading to the development of severe complications associated with increased mortality. Copeptin is a stable cleavage product of the precursor of arginine vasopressin, a key-regulator in hemodynamic homeostasis. Copeptin is currently considered a reliable prognostic marker in a wide variety of diseases other than cirrhosis. The present study aimed to assess copeptin, both experimentally and clinically, as a potential biomarker of hemodynamic derangement and to evaluate its prognostic significance in cirrhosis.

Materials and Methods

Two studies were executed: 1) in 18 thioacetamide-induced cirrhotic rats and 5 control rats, plasma copeptin and hemodynamic measurements were performed, 2) in 61 cirrhotic patients, serum copeptin concentration was measured in samples collected at time of registration at the waiting list for liver transplantation. In 46 patients, also a second copeptin measurement was performed during follow-up while registered at the waiting list for liver transplantation. To determine the association of serum copeptin and clinical data with outcome, Cox proportional hazard regression analysis and Kaplan Meier analysis were performed.

Results

Plasma copeptin concentration was significantly higher in cirrhotic rats than in controls (1.6 ± 0.5 vs. 0.9 ± 0.1 pmol/L, p< 0.01) and was negatively correlated to the mean arterial blood pressure (r = -0.574, p = 0.013). In cirrhotic patients, serum copeptin concentration was high [11.0 (5.2–24.0) pmol/L] and increased significantly during the time of registration at the waiting list for liver transplantation. MELD and MELD-sodium score were significantly correlated to serum copeptin [MELD: (r = 0.33, p = 0.01), MELD-sodium: (r = 0.29, p = 0.02)], also at time of the second copeptin measurement [MELD and MELD-sodium: r = 0.39, p< 0.01]. In cirrhotic humans, serum copeptin concentration was significantly associated with outcome, independently of the MELD and MELD-sodium score. Patients with a low serum copeptin concentration at time of registration at the liver transplant waiting list had significantly better transplant-free survival rates at 3, 6 and 12 months of follow-up as compared to those with a high serum copeptin concentration (Log-rank: p< 0.01, p< 0.01 and p = 0.02 respectively).

Conclusions

Circulating copeptin levels are elevated in rats and humans with cirrhosis. Copeptin is independently associated with outcome in cirrhotic patients awaiting liver transplantation.  相似文献   

10.
OBJECTIVE: To review all patients on a current general practice orthopaedic waiting list for outpatient appointments with regard to accuracy of the list, clinical priority, and need for further radiological investigation before hospital attendance. DESIGN: Record review by one general practitioner and a radiologist, and discussion with patients of management alternatives. SETTING: Six partner city centre urban fund-holding general practice, list size 8651 (29% low deprivation payment status). SUBJECTS: 116 adults on an orthopaedic waiting list. MAIN OUTCOME MEASURES: List accuracy (patient details and status on waiting list); clinical priority (severity of condition); further investigations (results of tests after radiological review). RESULTS: 32 patients (28%) were removed from the waiting list because of inaccuracies. 14 patients were considered to be high priority and referred to other hospitals by utilising waiting list initiative funds. Of these patients, five agreed to referral to another hospital (treatment completed on average within three months of rereferral), six did not wish to be rereferred, and two did not attend to discuss the offer and remained on the original waiting list. One prioritised patient had further radiological investigations, was reassured, and was taken off the waiting list. 10 patients had further investigations. These resulted in six patients being referred to other hospitals, three being taken off the waiting list, and one seeking private care. CONCLUSIONS: Systematic review of patients on an orthopaedic waiting list of one general practice, though time consuming, led to the identification of inaccuracies in the list and changes in management. Costs need further evaluation, but if the findings occur widely substantial benefits could be achieved for patients.  相似文献   

11.
One of the most visible and contentious issues regarding the fairness of the original system of organ procurement and allocation is the argument that it resulted in great disparities in the total amount of time a patient waited for an organ (i.e. the time from registration at a transplantation center to transplant), depending on where he or she lived. In an attempt to resolve this debate, Congress charged the National Academy of Sciences, Institute of Medicine to perform an independent study of the original system and proposed rule changes. In an analysis of approximately 68,000 transplant waiting list records, the committee developed several conclusions and recommendations largely specific to liver transplantation policies. The purpose of this paper is to describe both the results of the study and the statistical foundations of the mixed-effects multinomial logistic regression model that led to the committee's conclusions.  相似文献   

12.
The success of liver transplantation has resulted in a dramatic organ shortage. Each year, a considerable number of patients on the liver transplantation waiting list die without receiving an organ transplant or are delisted due to disease progression. Even after a successful transplantation, rejection and side effects of immunosuppression remain major concerns for graft survival and patient morbidity. Experimental animal research has been essential to the success of liver transplantation and still plays a pivotal role in the development of clinical transplantation practice. In particular, the porcine orthotopic liver transplantation model (OLTx) is optimal for clinically oriented research for its close resemblance to human size, anatomy, and physiology. Decompression of intestinal congestion during the anhepatic phase of porcine OLTx is important to guarantee reliable animal survival. The use of an active porto-caval-jugular shunt achieves excellent intestinal decompression. The system can be used for short-term as well as long-term survival experiments. The following protocol contains all technical information for a stable and reproducible liver transplantation model in pigs including post-operative animal care.  相似文献   

13.
Successful and consistent isolation of primary human hepatocytes remains a challenge for both cell-based therapeutics/transplantation and laboratory research. Several centres around the world have extensive experience in the isolation of human hepatocytes from non-diseased livers obtained from donor liver surplus to surgical requirement or at hepatic resection for tumours. These livers are an important but limited source of cells for therapy or research. The capacity to isolate cells from diseased liver tissue removed at transplantation would substantially increase availability of cells for research. However no studies comparing the outcome of human hepatocytes isolation from diseased and non-diseased livers presently exist. Here we report our experience isolating human hepatocytes from organ donors, non-diseased resected liver and cirrhotic tissue. We report the cell yields and functional qualities of cells isolated from the different types of liver and demonstrate that a single rigorous protocol allows the routine harvest of good quality primary hepatocytes from the most commonly accessible human liver tissue samples.  相似文献   

14.
Heart transplantation is limited by the lack of donor organs. Twenty years after the start of the Dutch transplant programmes in Rotterdam and Utrecht the situation has even worsened, despite efforts to increase the donor pool. The Dutch situation seems to be worse than in other surrounding countries, and several factors that may influence donor organ availability and organ utilisation are discussed. The indications and contraindications for heart transplantation are presented, which are rather restrictive in order to select optimal recipients for the scarce donor hearts. Detailed data on donor hearts, rejected for transplantation, are shown to give some insight into the difficult process of dealing with marginal donor organs. It is concluded that with the current low numbers of acceptable quality donor hearts, there is no lack of capacity in the two transplanting centres nor is the waiting list limiting the number of transplants. The influence of our current legal system on organ donation, which requires (prior) permission from donor and relatives, is probably limited. The most important determinants of donor organ availability are: 1. The potential donor pool, consisting of brain dead victims of (traffic) accidents and CVAs and 2. Lack of consent to a request for donation. The potential donor pool is remarkably small in the Netherlands, due to relatively low numbers of (traffic) accidents, with an almost equal number of CVA-related brain dead patients compared with neighbouring countries. Lack of consent can only be pushed back by improved public awareness of the importance of donation and improved skills of professionals in asking permission in case there is no previous consent.  相似文献   

15.
BackgroundPublic and scientific concerns about the social gradient of end-stage renal disease and access to renal replacement therapies are increasing. This study investigated the influence of social inequalities on the (i) access to renal transplant waiting list, (ii) access to renal transplantation and (iii) patients’ survival.MethodsAll incident adult patients with end-stage renal disease who lived in Bretagne, a French region, and started dialysis during the 2004–2009 period were geocoded in census-blocks. To each census-block was assigned a level of neighborhood deprivation and a degree of urbanization. Cox proportional hazards models were used to identify factors associated with each study outcome.ResultsPatients living in neighborhoods with low level of deprivation had more chance to be placed on the waiting list and less risk of death (HR = 1.40 95%CI: [1.1–1.7]; HR = 0.82 95%CI: [0.7–0.98]), but this association did not remain after adjustment for the patients’ clinical features. The likelihood of receiving renal transplantation after being waitlisted was not associated with neighborhood deprivation in univariate and multivariate analyses.ConclusionsIn a mixed rural and urban French region, patients living in deprived or advantaged neighborhoods had the same chance to be placed on the waiting list and to undergo renal transplantation. They also showed the same mortality risk, when their clinical features were taken into account.  相似文献   

16.
High plasma fibroblast growth factor-23 (FGF23) concentration predicts the risk of death and poor outcomes in patients with chronic kidney disease or chronic heart failure. We checked if FGF23 concentration could be modified in patients with end stage liver disease (ESLD) and predict mortality. We measured plasma FGF23 in 200 patients with ESLD registered on a liver transplant waiting list between January 2005 and October 2008. We found that median plasma FGF23 concentration was above normal values in 63% of the patients. Increased FGF23 concentration was not explained by its classical determinants: hyperphosphataemia, increased calcitriol concentration or decreased renal function. FGF23 concentration correlated with the MELD score, serum sodium concentration, and GFR. Forty-six patients died before being transplanted and 135 underwent liver transplantation. We analyzed the prognostic value of FGF23 levels. Mortality was significantly associated with FGF23 levels, the MELD score, serum sodium concentration and glomerular filtration rate. On multivariate analyses only FGF23 concentration was associated with mortality. FGF23 levels were independent of the cause of the liver disease. To determine if the damaged liver can produce FGF23 we measured plasma FGF23 concentration and liver FGF23 mRNA expression in control and diethyl-nitrosamine (DEN)-treated mice. FGF23 plasma levels increased with the apparition of liver lesions in DEN-treated mice and that FGF23 mRNA expression, which was undetectable in the liver of control mice, markedly increased with the development of liver lesions. The correlation between FGF23 plasma concentration and FGF23 mRNA expression in DEN-treated mice suggests that FGF23 production by the liver accounts for the increased plasma FGF23 concentration. In conclusion chronic liver lesions can induce expression of FGF23 mRNA leading to increased FGF23 concentration, which is associated with a higher mortality in patients on a liver-transplant waiting list. In these patients FGF23 concentration was the best predictor of mortality.  相似文献   

17.
The EuroTransplant Kidney Allocation System (ETKAS) aims at allocating organs to patients on the waiting list fairly whilst optimizing HLA match grades. ETKAS currently considers the number of HLA-A, -B, -DR mismatches. Evidently, epitope matching is biologically and clinically more relevant. We here executed ETKAS-based computer simulations to evaluate the impact of epitope matching on allocation and compared the strategies. A virtual population of 400,000 individuals was generated using the National Marrow Donor Program (NMDP) haplotype frequency dataset of 2011. Using this population, a waiting list of 10,400 patients was constructed and maintained during simulation, matching the 2015 Eurotransplant Annual Report characteristics. Unacceptable antigens were assigned randomly relative to their frequency using HLAMatchmaker. Over 22,600 kidneys were allocated in 10 years in triplicate using Markov Chain Monte Carlo simulations on 32-CPU-core cloud-computing instances. T-cell epitopes were calculated using the www.pirche.com portal. Waiting list effects were evaluated against ETKAS for five epitope matching scenarios. Baseline simulations of ETKAS slightly overestimated reported average HLA match grades. The best balanced scenario maintained prioritisation of HLA A-B-DR fully matched donors while replacing the HLA match grade by PIRCHE-II score and exchanging the HLA mismatch probability (MMP) by epitope MMP. This setup showed no considerable impact on kidney exchange rates and waiting time. PIRCHE-II scores improved, whereas the average HLA match grade diminishes slightly, yet leading to an improved estimated graft survival. We conclude that epitope-based matching in deceased donor kidney allocation is feasible while maintaining equal balances on the waiting list.  相似文献   

18.
《FEBS letters》1986,201(1):20-34
Activities of alanine:glyoxylate aminotransferase in the livers of two patients with primary hyperoxaluria type I were substantially lower than those found in five control human livers. Detailed subcellular fractionation of one of the hyperoxaluric livers, compared with a control liver, showed that there was a complete absence of peroxisomal alanine:glyoxylate aminotransferase. This enzyme deficiency explains most of the biochemical characteristics of the disease and means that primary hyperoxaluria type I should be added to the rather select list of peroxisomal disorders.  相似文献   

19.
Grompe M 《Human cell》1999,12(4):171-180
Orthotopic liver transplantation is the treatment of choice for many inherited and acquired liver diseases. Unfortunately, the supply of donor organs is limiting and therefore many patients cannot benefit from this therapy. In contrast, hepatocyte suspensions can be isolated from a single donor liver can be transplanted into several hosts, and this procedure may help overcome the shortage in donor livers. In classic hepatocyte transplantation, however, only 1% of the liver mass or less can be replaced by donor cells. Recently though, we have used a mouse model of hereditary tyrosinemia to show that > 90% of host hepatocytes can be replaced by a small number of transplanted donor cells in a process we term "therapeutic liver repopulation". This phenomenon is analogous to repopulation of the hematopoietic system after bone marrow transplantation. Liver repopulation occurs when transplanted cells have a growth advantage in the setting of damage to recipient liver cells. Here we will review the current knowledge of this process and discuss the hopeful implications for treatment of liver diseases.  相似文献   

20.
Current liver transplantation strategies face severe shortcomings owing to scarcity of donors, immunogenicity, prohibitive costs and poor survival rates. Due to the lengthy list of patients requiring transplant, high mortality rates are observed during the endless waiting period. Tissue engineering could be an alternative strategy to regenerate the damaged liver and improve the survival and quality of life of the patient. The development of an ideal scaffold for liver tissue engineering depends on the nature of the scaffold, its architecture and the presence of growth factors and recognition motifs. Biomimetic scaffolds can simulate the native extracellular matrix for the culture of hepatocytes to enable them to exhibit their functionality both in vitro and in vivo. This review highlights the physiology and pathophysiology of liver, the current treatment strategies, use of various scaffolds, incorporation of adhesion motifs, growth factors and stem cells that can stabilize and maintain hepatocyte cultures for a long period.  相似文献   

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