AIM: To compare outcomes between single and dual en bloc(EB) kidney transplants(KT) from small pediatric donors. METHODS: Monocentric nonprospective review of KTs from pediatric donors ≤ 5 years of age. Dual EB KT wa...AIM: To compare outcomes between single and dual en bloc(EB) kidney transplants(KT) from small pediatric donors. METHODS: Monocentric nonprospective review of KTs from pediatric donors ≤ 5 years of age. Dual EB KT was defined as keeping both donor kidneys attached tothe inferior vena cava and aorta, which were then used as venous and arterial conduits for the subsequent transplant into a single recipient. Donor age was less useful than either donor weight or kidney size in decision-making for kidney utilization as kidneys from donors < 8 kg or kidneys < 6 cm in length were not transplanted. Post-transplant management strategies were standardized in all patients.RESULTS: From 2002-2015, 59 KTs were performed including 34 dual EB and 25 single KTs. Mean age of donors(17 mo vs 38 mo, P < 0.001), mean weight(11.0 kg vs 17.4 kg, P = 0.046) and male donors(50% vs 84%, P = 0.01) were lower in the dual EB compared to the single KT group, respectively. Mean cold ischemia time(21 h), kidney donor profile index(KDPI; 73% vs 62%) and levels of serum creatinine(SCr, 0.37 mg/d L vs 0.49 mg/d L, all P = NS) were comparable in the dual EB and single KT groups, respectively. Actuarial graft and patient survival rates at 5-years follow-up were comparable. There was one case of thrombosis resulting in graft loss in each group. Delayed graft function incidence(12% dual EB vs 20% single KT, P = NS) was slightly lower in dual EB KT recipients. Initial duration of hospital stay(mean 5.4 d vs 5.6 d) and the one-year incidences of acute rejection(6% vs 16%), operative complications(3% vs 4%), and major infection were comparable in the dual EB and single KT groups, respectively(all P = NS). Mean 12 mo SCr and abbreviated MDRD levels were 1.17 mg/d L vs 1.35 mg/d L and 72.5 m L/min per 1.73 m^2 vs 60.5 m L/min per 1.73 m^2(both P = NS) in the dual EB and single KT groups, respectively. CONCLUSION: By transplanting kidneys from young pediatric donors into adult recipients, one can effectively expand the limited donor pool and achieve excellent medium-term outcomes.展开更多
ABO incompatible kidney transplantation(ABOi-KT) was previously considered to be an absolute contraindication for patients with end-stage kidney disease(ESKD) due to hyperacute rejection related to blood type barrier....ABO incompatible kidney transplantation(ABOi-KT) was previously considered to be an absolute contraindication for patients with end-stage kidney disease(ESKD) due to hyperacute rejection related to blood type barrier. Since the first successful series of ABOi-KT was reported, ABOi-KT is performed increasingly all over the world. ABOi-KT has led to an expanded donor pool and reduced the number of patients with ESKD awaiting deceased kidney transplantation(KT). Intensified immunosuppression and immunological understanding has helped to shape current desensitization protocols. Consequently, in recent years, ABOi-KT outcome is comparable to ABO compatible KT(ABOc-KT). However, many questions still remain unanswered. In ABOi-KT, there is an additional residual immunological risk that maylead to allograft damage, despite using current diverse but usually intensified immunosuppressive protocols at the expense of increasing risk of infection and possibly malignancy. Notably, in ABOi-KT, desensitization and antibody reduction therapies have increased the cost of KT. Reassuringly, there has been an evolution in ABOiKT leading to a simplification of protocols over the last decade. This review provides an overview of the history, outcome, protocol, advantages and disadvantages in ABOi-KT, and focuses on whether ABOi-KT should be recommended as a therapeutic option of KT in the future.展开更多
Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK ne...Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy(BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research.展开更多
This article reviews the current evidence and knowledge of progressive liver fibrosis after pediatric liver transplantation.This often-silent histologic finding is common in long-term survivors and may lead to allogra...This article reviews the current evidence and knowledge of progressive liver fibrosis after pediatric liver transplantation.This often-silent histologic finding is common in long-term survivors and may lead to allograft dysfunction in advanced stages.Surveillance through protocolized liver allograft biopsy remains the gold standard for diagnosis,and recent evidence suggests that chronic inflammation precedes fibrosis.展开更多
Data from studies analyzing the differentiation and functional connectivity of embryo nic neural tissue grafted into the mammalian nervous system has led to the clinical testing of the fetal graft approach in patients...Data from studies analyzing the differentiation and functional connectivity of embryo nic neural tissue grafted into the mammalian nervous system has led to the clinical testing of the fetal graft approach in patients with neurodegenerative disease.While some success has been achieved,ethical concerns have led to a search for alternative therapeutic strategies,mostly exploring the use of neural precursors or neurons derived from pluripotent stem cells to replace damaged host neurons and restore lost circuitries.These more recent studies address questions of graft viability,differentiation,and connectivity similar to those posed by researchers in earlier fetal transplant work,thus reviews of the fetal graft literature may inform and help guide ongoing research in the stem cell/organoid field.This brief review describes some key observations from research into the transplantation of neural tissue into the rat visual syste m,focusing on grafts of the fetal supe rior colliculus(tectal grafts) into neonatal or adult hosts.In neonate hosts,grafts quickly develop connections with the underlying host mid b rain and attain a morphology typical of mature grafts by about 2 weeks.G rafts consistently contain numerous localized regions which,based on neurofibrillar staining,neuronal morphology(Golgi),neurochemistry,receptor expression,and glial architecture,are homologous to the stratum griseum supe rficiale of normal superior colliculus.These localized "patches" are also seen after explant culture and when donor tectal tissue is dissociated and reaggregated prior to transplantation.In almost all circumstances,host retinal innervation is restricted to these localized patches,but only those that are located adjacent to the graft surfa ce.Synapses are formed and there is evidence of functional drive.The only exception occurs when Schwann cells are added to dissociated tecta prior to reaggregation.In these co-grafts,the peripheral glia appear to compete with local target fa ctors and host retinal ingrowth is more widespread.Other afferent systems(e.g.,host co rtex,serotonin) show different patterns of innervation.The host cortical input originates more from extrastriate regions and establishes functional excitato ry synapses with grafted neurons.Finally,when grafted into optic tra ct lesions in adult rat hosts,spontaneously regrowing host retinal axons retain the capacity to selectively innervate the localized patches in embryonic tectal grafts,showing that the specific affinities between adult retinal axons and their targets are not lost during regeneration.While the research described here provides some pertinent information about development and plasticity in visual pathways,a more general aim is to highlight how the review of the extensive fetal graft lite rature may aid in an appreciation of the positive(and negative) fa ctors that influence survival,differentiation,connectivity and functionality of engineered cells and organoids transplanted into the central nervous system.展开更多
Mycophenolic acid(MPA),the active moiety of both mycophenolate mofetil(MMF)and enteric-coated mycophenolate sodium(EC-MPS),serves as a primary immunosuppressant for maintaining solid organ transplants.Therapeutic drug...Mycophenolic acid(MPA),the active moiety of both mycophenolate mofetil(MMF)and enteric-coated mycophenolate sodium(EC-MPS),serves as a primary immunosuppressant for maintaining solid organ transplants.Therapeutic drug monitoring(TDM)enhances treatment outcomes through tailored approaches.This study aimed to develop an evidence-based guideline for MPA TDM,facilitating its rational application in clinical settings.The guideline plan was drawn from the Institute of Medicine and World Health Organization(WHO)guidelines.Using the Delphi method,clinical questions and outcome indicators were generated.Systematic reviews,Grading of Recommendations Assessment,Development,and Evaluation(GRADE)evidence quality evaluations,expert opinions,and patient values guided evidence-based suggestions for the guideline.External reviews further refined the recommendations.The guideline for the TDM of MPA(IPGRP-2020CN099)consists of four sections and 16 recommendations encompassing target populations,monitoring strategies,dosage regimens,and influencing factors.High-risk populations,timing of TDM,area under the curve(AUC)versus trough concentration(C0),target concentration ranges,monitoring frequency,and analytical methods are addressed.Formulation-specific recommendations,initial dosage regimens,populations with unique considerations,pharmacokinetic-informed dosing,body weight factors,pharmacogenetics,and drug–drug interactions are covered.The evidence-based guideline offers a comprehensive recommendation for solid organ transplant recipients undergoing MPA therapy,promoting standardization of MPA TDM,and enhancing treatment efficacy and safety.展开更多
Patients listed for organ transplant frequently have severe coronary artery disease(CAD), which may be treated with drug eluting stents(DES). Everolimus and zotarolimus eluting stents are commonly used. Newer generati...Patients listed for organ transplant frequently have severe coronary artery disease(CAD), which may be treated with drug eluting stents(DES). Everolimus and zotarolimus eluting stents are commonly used. Newer generation biolimus and novolimus eluting biodegradable stents are becoming increasingly popular. Patients undergoing transplant surgery soon after the placement of DES are at increased risk of stent thrombosis(ST) in the perioperative period. Dual antiplatelet therapy(DAPT) with aspirin and a P2Y12 inhibitor such as clopidogrel, prasugrel and ticagrelor is instated post stenting to decrease the incident of ST. Cangrelor has recently been approved by Food and Drug Administration and can be used as a bridging antiplatelet drug. The risk of ischemia vs bleeding must be considered when discontinuing or continuing DAPT for surgery. Though living donor transplant surgery is an elective procedure and can be optimally timed, cadaveric organ availability is unpredictable, therefore, discontinuation of antiplatelet medication cannot be optimally timed. The type of stent and timing of transplant surgery can be of utmost importance. Many platelet function point of care tests such as Light Transmittance Aggregrometry, Thromboelastography Platelet Mapping, VerifyN ow, Multiple Electrode Aggregrometry are used to assess bleeding risk and guide perioperative platelet transfusion. Response to allogenic platelet transfusion to control severe intraoperative bleeding may differ with the antiplatelet drug. In stent thrombosis is an emergency where management with either a drug eluting balloon or a DES has shown superior outcomes. Post-transplant complications often involved stenosis of an important vessel that may need revascularization. DES are now used for endovascular interventions for transplant orthotropic heart CAD, hepatic artery stenosis post liver transplantation, transplant renal artery stenosis following kidney transplantation, etc. Several antiproliferative drugs used in the DES are inhibitors of mammalian target of rapamycin. Thus they are used for post-transplant immunosuppression to prevent acute rejection in recipients with heart, liver, lung and kidney transplantation. This article describes in detail the various perioperative challenges encountered in organ transplantation surgery and patients with drug eluting stents.展开更多
Stem cell transplantation has brought new hope for the treatment of neurological diseases.The key to stem cell therapy lies in inducing the specific differentiation of stem cells into nerve cells.Because the different...Stem cell transplantation has brought new hope for the treatment of neurological diseases.The key to stem cell therapy lies in inducing the specific differentiation of stem cells into nerve cells.Because the differentiation of stem cells in vitro and in vivo is affected by multiple factors,the final differentiation outcome is strongly associated with the microenvironment in which the stem cells are located.Accordingly,the optimal microenvironment for inducing stem cell differentiation is a hot topic.EGb761 is extracted from the leaves of the Ginkgo biloba tree.It is used worldwide and is becoming one of the focuses of stem cell research.Studies have shown that EGb761 can antagonize oxygen free radicals,stabilize cell membranes,promote neurogenesis and synaptogenesis,increase the level of brain-derived neurotrophic factors,and replicate the environment required during the differentiation of stem cells into nerve cells.This offers the possibility of using EGb761 to induce the differentiation of stem cells,facilitating stem cell transplantation.To provide a comprehensive reference for the future application of EGb761 in stem cell therapy,we reviewed studies investigating the influence of EGb761 on stem cells.These started with the composition and neuropharmacology of EGb761,and eventually led to the finding that EGb761 and some of its important components play important roles in the differentiation of stem cells and the protection of a beneficial microenvironment for stem cell transplantation.展开更多
BACKGROUND Pancreas transplant is the only treatment that establishes normal glucose levels for patients diagnosed with diabetes.However,since 2005,no comprehensive analysis has compared survival outcomes of:(1)Simult...BACKGROUND Pancreas transplant is the only treatment that establishes normal glucose levels for patients diagnosed with diabetes.However,since 2005,no comprehensive analysis has compared survival outcomes of:(1)Simultaneous pancreas-kidney(SPK)transplant;(2)Pancreas after kidney(PAK)transplant;and(3)Pancreas transplant alone(PTA)to waitlist survival.AIM To explore the outcomes of pancreas transplants in the United States during the decade 2008-2018.METHODS Our study utilized the United Network for Organ Sharing Standard Transplant Analysis and Research file.Pre-and post-transplant recipient and waitlist characteristics and the most recent recipient transplant and mortality status were used.We included all patients with type I diabetes listed for pancreas or kidneypancreas transplant between May 31,2008 and May 31,2018.Patients were grouped into one of three transplant types:SPK,PAK,or PTA.RESULTS The adjusted Cox proportional hazards models comparing survival between transplanted and non-transplanted patients in each transplant type group showed that patients who underwent an SPK transplant exhibited a significantly reduced hazard of mortality[hazard ratio(HR)=0.21,95%confidence intervals(CI):0.19-0.25]compared to those not transplanted.Neither PAK transplanted patients(HR=1.68,95%CI:0.99-2.87)nor PTA patients(HR=1.01,95%CI:0.53-1.95)experienced significantly different hazards of mortality compared to patients who did not receive a transplant.CONCLUSION When assessing each of the three transplant types,only SPK transplant offered a survival advantage compared to patients on the waiting list.PKA and PTA transplanted patients demonstrated no significant differences compared to patients who did not receive a transplant.展开更多
Viral hepatitis infections are a great burden in children who have received liver transplant.Hepatotropic viruses can cause liver inflammation that can develop into liver graft fibrosis and cirrhosis over the long ter...Viral hepatitis infections are a great burden in children who have received liver transplant.Hepatotropic viruses can cause liver inflammation that can develop into liver graft fibrosis and cirrhosis over the long term.Immunological reactions due to viral hepatitis infections are associated with or can mimic graft rejection,rendering the condition difficult to manage.Prevention strategies using vaccinations are agreeable to patients,safe,cost-effective and practical.Hence,strategies to eliminate viral hepatitis A and B focus mainly on immunization programmes for children who have received a liver transplant.Although a vaccine has been developed to prevent hepatitis C and E viruses,its use is not licensed worldwide.Consequently,eliminating hepatitis C and E viruses mainly involves early detection in children with suspected cases and effective treatment with antiviral therapy.Good hygiene and sanitation are also important to prevent hepatitis A and E infections.Donor blood products and liver grafts should be screened for hepatitis B,C and E in children who are undergoing liver transplantation.Future research on early detection of viral hepatitis infections should include molecular techniques for detecting hepatitis B and E.Moreover,novel antiviral drugs for eradicating viral hepatitis that are highly effective and safe are needed for children who have undergone liver transplantation.展开更多
AIM To compare survival of kidney transplants from deceased extended criteria donors(ECD)according to:(1)donor graft histological score;and(2)allocation of high score grafts either to single(SKT)or dual(DKT)transplant...AIM To compare survival of kidney transplants from deceased extended criteria donors(ECD)according to:(1)donor graft histological score;and(2)allocation of high score grafts either to single(SKT)or dual(DKT)transplant.METHODS Renal biopsy was performed as part of either a newly adopted DKT protocol,or of surveillance protocol in the past.A total 185 ECD graft recipients were categorized according to pre-implantation graft biopsy into 3 groups:SKT with graft score 1 to 4[SKT(1-4),n=102];SKT with donor graft score 5 to 8[SKT(>4),n=30];DKT with donor graft score 5 to 7(DKT,n=53).Graft and patient survival were analyzed by Kaplan-Meier curves and compared by log-rank test.Mean number of functioning graft years by transplant reference,and mean number of dialysis-free life years by donor reference in recipients were also calculated at 1,3 and 6 years from transplantation.RESULTS There were no statistically significant differences in graft and patient survival between SKT(1-4)and SKT(>4),and between SKT(>4)and DKT.Recipient renal function(plasma creatinine and creatinine clearance)at 1 years did not differ in SKT(1-4)and SKT(>4)(plasma creatinine 1.71±0.69 and 1.69±0.63 mg/dL;creatinine clearance 49.6+18.5 and 52.6+18.8 m L/min,respectively);DKT showed statistically lower plasma creatinine(1.46±0.57,P<0.04)but not different creatinine clearance(55.4+20.4).Due to older donor age in the DKT group,comparisons were repeated in transplants from donors older than 70 years,and equal graft and patient survival in SKT and DKT were confirmed.Total mean number of functioning graft years by transplant reference at 1,3 and 6 post-transplant years were equal between the groups,but mean number of dialysis-free life years by donor reference were significantly higher in SKT(mean difference compared to DKT at 6 years:292[IQR 260-318]years/100 donors in SKT(1-4)and 292.5[(IQR 247.8-331.6)in SKT(>4)].CONCLUSION In transplants from clinically suitable ECD donors,graft survival was similar irrespective of pre-implantation biopsy score and of allocation to SKT or DKT.These results suggest use of caution in the use of histology as the only decision criteria for ECD organ allocation.展开更多
文摘AIM: To compare outcomes between single and dual en bloc(EB) kidney transplants(KT) from small pediatric donors. METHODS: Monocentric nonprospective review of KTs from pediatric donors ≤ 5 years of age. Dual EB KT was defined as keeping both donor kidneys attached tothe inferior vena cava and aorta, which were then used as venous and arterial conduits for the subsequent transplant into a single recipient. Donor age was less useful than either donor weight or kidney size in decision-making for kidney utilization as kidneys from donors < 8 kg or kidneys < 6 cm in length were not transplanted. Post-transplant management strategies were standardized in all patients.RESULTS: From 2002-2015, 59 KTs were performed including 34 dual EB and 25 single KTs. Mean age of donors(17 mo vs 38 mo, P < 0.001), mean weight(11.0 kg vs 17.4 kg, P = 0.046) and male donors(50% vs 84%, P = 0.01) were lower in the dual EB compared to the single KT group, respectively. Mean cold ischemia time(21 h), kidney donor profile index(KDPI; 73% vs 62%) and levels of serum creatinine(SCr, 0.37 mg/d L vs 0.49 mg/d L, all P = NS) were comparable in the dual EB and single KT groups, respectively. Actuarial graft and patient survival rates at 5-years follow-up were comparable. There was one case of thrombosis resulting in graft loss in each group. Delayed graft function incidence(12% dual EB vs 20% single KT, P = NS) was slightly lower in dual EB KT recipients. Initial duration of hospital stay(mean 5.4 d vs 5.6 d) and the one-year incidences of acute rejection(6% vs 16%), operative complications(3% vs 4%), and major infection were comparable in the dual EB and single KT groups, respectively(all P = NS). Mean 12 mo SCr and abbreviated MDRD levels were 1.17 mg/d L vs 1.35 mg/d L and 72.5 m L/min per 1.73 m^2 vs 60.5 m L/min per 1.73 m^2(both P = NS) in the dual EB and single KT groups, respectively. CONCLUSION: By transplanting kidneys from young pediatric donors into adult recipients, one can effectively expand the limited donor pool and achieve excellent medium-term outcomes.
文摘ABO incompatible kidney transplantation(ABOi-KT) was previously considered to be an absolute contraindication for patients with end-stage kidney disease(ESKD) due to hyperacute rejection related to blood type barrier. Since the first successful series of ABOi-KT was reported, ABOi-KT is performed increasingly all over the world. ABOi-KT has led to an expanded donor pool and reduced the number of patients with ESKD awaiting deceased kidney transplantation(KT). Intensified immunosuppression and immunological understanding has helped to shape current desensitization protocols. Consequently, in recent years, ABOi-KT outcome is comparable to ABO compatible KT(ABOc-KT). However, many questions still remain unanswered. In ABOi-KT, there is an additional residual immunological risk that maylead to allograft damage, despite using current diverse but usually intensified immunosuppressive protocols at the expense of increasing risk of infection and possibly malignancy. Notably, in ABOi-KT, desensitization and antibody reduction therapies have increased the cost of KT. Reassuringly, there has been an evolution in ABOiKT leading to a simplification of protocols over the last decade. This review provides an overview of the history, outcome, protocol, advantages and disadvantages in ABOi-KT, and focuses on whether ABOi-KT should be recommended as a therapeutic option of KT in the future.
文摘Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy(BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research.
文摘This article reviews the current evidence and knowledge of progressive liver fibrosis after pediatric liver transplantation.This often-silent histologic finding is common in long-term survivors and may lead to allograft dysfunction in advanced stages.Surveillance through protocolized liver allograft biopsy remains the gold standard for diagnosis,and recent evidence suggests that chronic inflammation precedes fibrosis.
文摘Data from studies analyzing the differentiation and functional connectivity of embryo nic neural tissue grafted into the mammalian nervous system has led to the clinical testing of the fetal graft approach in patients with neurodegenerative disease.While some success has been achieved,ethical concerns have led to a search for alternative therapeutic strategies,mostly exploring the use of neural precursors or neurons derived from pluripotent stem cells to replace damaged host neurons and restore lost circuitries.These more recent studies address questions of graft viability,differentiation,and connectivity similar to those posed by researchers in earlier fetal transplant work,thus reviews of the fetal graft literature may inform and help guide ongoing research in the stem cell/organoid field.This brief review describes some key observations from research into the transplantation of neural tissue into the rat visual syste m,focusing on grafts of the fetal supe rior colliculus(tectal grafts) into neonatal or adult hosts.In neonate hosts,grafts quickly develop connections with the underlying host mid b rain and attain a morphology typical of mature grafts by about 2 weeks.G rafts consistently contain numerous localized regions which,based on neurofibrillar staining,neuronal morphology(Golgi),neurochemistry,receptor expression,and glial architecture,are homologous to the stratum griseum supe rficiale of normal superior colliculus.These localized "patches" are also seen after explant culture and when donor tectal tissue is dissociated and reaggregated prior to transplantation.In almost all circumstances,host retinal innervation is restricted to these localized patches,but only those that are located adjacent to the graft surfa ce.Synapses are formed and there is evidence of functional drive.The only exception occurs when Schwann cells are added to dissociated tecta prior to reaggregation.In these co-grafts,the peripheral glia appear to compete with local target fa ctors and host retinal ingrowth is more widespread.Other afferent systems(e.g.,host co rtex,serotonin) show different patterns of innervation.The host cortical input originates more from extrastriate regions and establishes functional excitato ry synapses with grafted neurons.Finally,when grafted into optic tra ct lesions in adult rat hosts,spontaneously regrowing host retinal axons retain the capacity to selectively innervate the localized patches in embryonic tectal grafts,showing that the specific affinities between adult retinal axons and their targets are not lost during regeneration.While the research described here provides some pertinent information about development and plasticity in visual pathways,a more general aim is to highlight how the review of the extensive fetal graft lite rature may aid in an appreciation of the positive(and negative) fa ctors that influence survival,differentiation,connectivity and functionality of engineered cells and organoids transplanted into the central nervous system.
基金supported by the National Natural Science Foundation of China(NSFC)(No.72304007)the Huatong Guokang Medical Research Fund(No.2023HT010)。
文摘Mycophenolic acid(MPA),the active moiety of both mycophenolate mofetil(MMF)and enteric-coated mycophenolate sodium(EC-MPS),serves as a primary immunosuppressant for maintaining solid organ transplants.Therapeutic drug monitoring(TDM)enhances treatment outcomes through tailored approaches.This study aimed to develop an evidence-based guideline for MPA TDM,facilitating its rational application in clinical settings.The guideline plan was drawn from the Institute of Medicine and World Health Organization(WHO)guidelines.Using the Delphi method,clinical questions and outcome indicators were generated.Systematic reviews,Grading of Recommendations Assessment,Development,and Evaluation(GRADE)evidence quality evaluations,expert opinions,and patient values guided evidence-based suggestions for the guideline.External reviews further refined the recommendations.The guideline for the TDM of MPA(IPGRP-2020CN099)consists of four sections and 16 recommendations encompassing target populations,monitoring strategies,dosage regimens,and influencing factors.High-risk populations,timing of TDM,area under the curve(AUC)versus trough concentration(C0),target concentration ranges,monitoring frequency,and analytical methods are addressed.Formulation-specific recommendations,initial dosage regimens,populations with unique considerations,pharmacokinetic-informed dosing,body weight factors,pharmacogenetics,and drug–drug interactions are covered.The evidence-based guideline offers a comprehensive recommendation for solid organ transplant recipients undergoing MPA therapy,promoting standardization of MPA TDM,and enhancing treatment efficacy and safety.
文摘Patients listed for organ transplant frequently have severe coronary artery disease(CAD), which may be treated with drug eluting stents(DES). Everolimus and zotarolimus eluting stents are commonly used. Newer generation biolimus and novolimus eluting biodegradable stents are becoming increasingly popular. Patients undergoing transplant surgery soon after the placement of DES are at increased risk of stent thrombosis(ST) in the perioperative period. Dual antiplatelet therapy(DAPT) with aspirin and a P2Y12 inhibitor such as clopidogrel, prasugrel and ticagrelor is instated post stenting to decrease the incident of ST. Cangrelor has recently been approved by Food and Drug Administration and can be used as a bridging antiplatelet drug. The risk of ischemia vs bleeding must be considered when discontinuing or continuing DAPT for surgery. Though living donor transplant surgery is an elective procedure and can be optimally timed, cadaveric organ availability is unpredictable, therefore, discontinuation of antiplatelet medication cannot be optimally timed. The type of stent and timing of transplant surgery can be of utmost importance. Many platelet function point of care tests such as Light Transmittance Aggregrometry, Thromboelastography Platelet Mapping, VerifyN ow, Multiple Electrode Aggregrometry are used to assess bleeding risk and guide perioperative platelet transfusion. Response to allogenic platelet transfusion to control severe intraoperative bleeding may differ with the antiplatelet drug. In stent thrombosis is an emergency where management with either a drug eluting balloon or a DES has shown superior outcomes. Post-transplant complications often involved stenosis of an important vessel that may need revascularization. DES are now used for endovascular interventions for transplant orthotropic heart CAD, hepatic artery stenosis post liver transplantation, transplant renal artery stenosis following kidney transplantation, etc. Several antiproliferative drugs used in the DES are inhibitors of mammalian target of rapamycin. Thus they are used for post-transplant immunosuppression to prevent acute rejection in recipients with heart, liver, lung and kidney transplantation. This article describes in detail the various perioperative challenges encountered in organ transplantation surgery and patients with drug eluting stents.
基金funded by the National Natural Science Foundation of China,No.81501185(to CR)the Key Research&Development Project of Shandong Province of China,No.2017GSF218043(to CR)the Science and Technology Planning Project of Yantai of China,No.2016WS017(to LNG),2017WS105(to HL)
文摘Stem cell transplantation has brought new hope for the treatment of neurological diseases.The key to stem cell therapy lies in inducing the specific differentiation of stem cells into nerve cells.Because the differentiation of stem cells in vitro and in vivo is affected by multiple factors,the final differentiation outcome is strongly associated with the microenvironment in which the stem cells are located.Accordingly,the optimal microenvironment for inducing stem cell differentiation is a hot topic.EGb761 is extracted from the leaves of the Ginkgo biloba tree.It is used worldwide and is becoming one of the focuses of stem cell research.Studies have shown that EGb761 can antagonize oxygen free radicals,stabilize cell membranes,promote neurogenesis and synaptogenesis,increase the level of brain-derived neurotrophic factors,and replicate the environment required during the differentiation of stem cells into nerve cells.This offers the possibility of using EGb761 to induce the differentiation of stem cells,facilitating stem cell transplantation.To provide a comprehensive reference for the future application of EGb761 in stem cell therapy,we reviewed studies investigating the influence of EGb761 on stem cells.These started with the composition and neuropharmacology of EGb761,and eventually led to the finding that EGb761 and some of its important components play important roles in the differentiation of stem cells and the protection of a beneficial microenvironment for stem cell transplantation.
基金This study was reviewed and approved by Mayo Clinic institutional review board(IRB application number 20-004621).
文摘BACKGROUND Pancreas transplant is the only treatment that establishes normal glucose levels for patients diagnosed with diabetes.However,since 2005,no comprehensive analysis has compared survival outcomes of:(1)Simultaneous pancreas-kidney(SPK)transplant;(2)Pancreas after kidney(PAK)transplant;and(3)Pancreas transplant alone(PTA)to waitlist survival.AIM To explore the outcomes of pancreas transplants in the United States during the decade 2008-2018.METHODS Our study utilized the United Network for Organ Sharing Standard Transplant Analysis and Research file.Pre-and post-transplant recipient and waitlist characteristics and the most recent recipient transplant and mortality status were used.We included all patients with type I diabetes listed for pancreas or kidneypancreas transplant between May 31,2008 and May 31,2018.Patients were grouped into one of three transplant types:SPK,PAK,or PTA.RESULTS The adjusted Cox proportional hazards models comparing survival between transplanted and non-transplanted patients in each transplant type group showed that patients who underwent an SPK transplant exhibited a significantly reduced hazard of mortality[hazard ratio(HR)=0.21,95%confidence intervals(CI):0.19-0.25]compared to those not transplanted.Neither PAK transplanted patients(HR=1.68,95%CI:0.99-2.87)nor PTA patients(HR=1.01,95%CI:0.53-1.95)experienced significantly different hazards of mortality compared to patients who did not receive a transplant.CONCLUSION When assessing each of the three transplant types,only SPK transplant offered a survival advantage compared to patients on the waiting list.PKA and PTA transplanted patients demonstrated no significant differences compared to patients who did not receive a transplant.
基金Supported by The Center of Excellence in Clinical Virology,Faculty of Medicine,King Chulalongkorn Memorial Hospital,Chulalongkorn University,Bangkok 10330,Thailand and Thai Pediatric Gastroenterology,Hepatology and Immunology(TPGHAI)Research Unit,Department of Pediatrics,Faculty of Medicine,King Chulalongkorn Memorial Hospital,Thai Red Cross,Chulalongkorn University,Bangkok 10330,Thailand.
文摘Viral hepatitis infections are a great burden in children who have received liver transplant.Hepatotropic viruses can cause liver inflammation that can develop into liver graft fibrosis and cirrhosis over the long term.Immunological reactions due to viral hepatitis infections are associated with or can mimic graft rejection,rendering the condition difficult to manage.Prevention strategies using vaccinations are agreeable to patients,safe,cost-effective and practical.Hence,strategies to eliminate viral hepatitis A and B focus mainly on immunization programmes for children who have received a liver transplant.Although a vaccine has been developed to prevent hepatitis C and E viruses,its use is not licensed worldwide.Consequently,eliminating hepatitis C and E viruses mainly involves early detection in children with suspected cases and effective treatment with antiviral therapy.Good hygiene and sanitation are also important to prevent hepatitis A and E infections.Donor blood products and liver grafts should be screened for hepatitis B,C and E in children who are undergoing liver transplantation.Future research on early detection of viral hepatitis infections should include molecular techniques for detecting hepatitis B and E.Moreover,novel antiviral drugs for eradicating viral hepatitis that are highly effective and safe are needed for children who have undergone liver transplantation.
文摘AIM To compare survival of kidney transplants from deceased extended criteria donors(ECD)according to:(1)donor graft histological score;and(2)allocation of high score grafts either to single(SKT)or dual(DKT)transplant.METHODS Renal biopsy was performed as part of either a newly adopted DKT protocol,or of surveillance protocol in the past.A total 185 ECD graft recipients were categorized according to pre-implantation graft biopsy into 3 groups:SKT with graft score 1 to 4[SKT(1-4),n=102];SKT with donor graft score 5 to 8[SKT(>4),n=30];DKT with donor graft score 5 to 7(DKT,n=53).Graft and patient survival were analyzed by Kaplan-Meier curves and compared by log-rank test.Mean number of functioning graft years by transplant reference,and mean number of dialysis-free life years by donor reference in recipients were also calculated at 1,3 and 6 years from transplantation.RESULTS There were no statistically significant differences in graft and patient survival between SKT(1-4)and SKT(>4),and between SKT(>4)and DKT.Recipient renal function(plasma creatinine and creatinine clearance)at 1 years did not differ in SKT(1-4)and SKT(>4)(plasma creatinine 1.71±0.69 and 1.69±0.63 mg/dL;creatinine clearance 49.6+18.5 and 52.6+18.8 m L/min,respectively);DKT showed statistically lower plasma creatinine(1.46±0.57,P<0.04)but not different creatinine clearance(55.4+20.4).Due to older donor age in the DKT group,comparisons were repeated in transplants from donors older than 70 years,and equal graft and patient survival in SKT and DKT were confirmed.Total mean number of functioning graft years by transplant reference at 1,3 and 6 post-transplant years were equal between the groups,but mean number of dialysis-free life years by donor reference were significantly higher in SKT(mean difference compared to DKT at 6 years:292[IQR 260-318]years/100 donors in SKT(1-4)and 292.5[(IQR 247.8-331.6)in SKT(>4)].CONCLUSION In transplants from clinically suitable ECD donors,graft survival was similar irrespective of pre-implantation biopsy score and of allocation to SKT or DKT.These results suggest use of caution in the use of histology as the only decision criteria for ECD organ allocation.