Organ transplantation and drug eluting stents:Perioperative challenges

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.

Relevance of ADAMTS13 to liver transplantation and surgery

A disintegrin-like and metalloproteinase with thrombospondin type-1 motifs 13(ADAMTS13) specifically cleaves unusually-large von Willebrand factor(VWF) multimers under high shear stress,and down-regulates VWF function to form platelet thrombi.Deficiency of plasma ADAMTS13 activity induces a life-threatening systemic disease,termed thrombotic microangiopathy(TMA) including thrombotic thrombocytopenic purpura(TTP).Children with advanced biliary cirrhosis due to congenital biliary atresia sometimes showed pathological features of TMA,with a concomitant decrease of plasma ADAMTS13 activity.Disappearance of their clinical findings of TTP after successful liver transplantation suggested that the liver is a major organ producing plasma ADAMTS13.In situ hybridization analysis showed that ADAMTS13 was produced by hepatic stellate cells.Subsequently,it was found that ADADTS13 was not merely responsible to development of TMA and TTP,but also related to some kinds of liver dysfunction after liver transplantation.Ischemia-reperfusion injury and acute rejection in liver transplant recipients were often associated with marked decrease of ADAMTS13 and concomitant formation of unusually large VWF multimers without findings of TMA/TTP.The similar phenomenon was observed also in patients who underwent hepatectomy for liver tumors.Imbalance between ADAMTS13 and VWF in the hepatic sinusoid might cause liver damage due to microcirculatory disturbance.It can be called as "local TTP like mechanism" which plays a crucial role in liver dysfunction after liver transplantation and surgery.

Proteomics for rejection diagnosis in renal transplant patients: Where are we now?

Rejection is one of the key factors that determine the long-term allograft function and survival in renal transplant patients. Reliable and timely diagnosis is important to treat rejection as early as possible. Allograft biopsies are not suitable for continuous monitoring of rejection. Thus, there is an unmet need for non-invasive methods to diagnose acute and chronic rejection. Proteomics in urine and blood samples has been explored for this purpose in 29 studies conducted since 2003. This review describes the different proteomic approaches and summarizes the results from the studies that examined proteomics for the rejection diagnoses. The potential limitations and open questions in establishing proteomic markers for rejection are discussed, including ongoing trials and future challenges to this topic.

Neural stem cell transplantation inhibits glial cell proliferation and P2X receptor-mediated neuropathic pain in spinal cord injury rats

P2X4 and P2X7 receptors play an important role in neuropathic pain after spinal cord injury. Regulation of P2X4 and P2X7 receptors can obviously reduce pain hypersensitivity after injury. To investigate the role of neural stem cell transplantation on P2X receptor-mediated neuropathic pain and explore related mechanisms, a rat model of spinal cord injury was prepared using the free-falling heavy body method with spinal cord segment 10 as the center. Neural stem cells were injected into the injured spinal cord segment using a micro-syringe. Expression levels of P2X4 and P2X7 receptors, neurofilament protein, and glial fibrillary acidic protein were determined by immunohistochemistry and western blot assay. In addition, sensory function was quantitatively assessed by current perception threshold. The Basso-Beattie-Bresnahan locomotor rating scale was used to assess neuropathological pain. The results showed that 4 weeks after neural stem cell transplantation, expression of neurofilament protein in the injured segment was markedly increased, while expression of glial fibrillary acidic protein and P2X4 and P2X7 receptors was decreased. At this time point, motor and sensory functions of rats were obviously improved, and neuropathic pain was alleviated. These findings demonstrated that neural stem cell transplantation reduced overexpression of P2X4 and P2X7 receptors, activated locomotor and sensory function reconstruction, and played an important role in neuropathic pain regulation after spinal cord injury. Therefore, neural stem cell transplantation is one potential option for relieving neuropathic pain mediated by P2X receptors.

Chondroitinase ABC combined with Schwann cell transplantation enhances restoration of neural connection and functional recovery following acute and chronic spinal cord injury

Schwann cell transplantation is considered one of the most promising cell-based therapy to repair injured spinal cord due to its unique growth-promoting and myelin-forming properties.A the Food and Drug Administration-approved Phase I clinical trial has been conducted to evaluate the safety of transplanted human autologous Schwann cells to treat patients with spinal cord injury.A major challenge for Schwann cell transplantation is that grafted Schwann cells are confined within the lesion cavity,and they do not migrate into the host environment due to the inhibitory barrier formed by injury-induced glial scar,thus limiting axonal reentry into the host spinal cord.Here we introduce a combinatorial strategy by suppressing the inhibitory extracellular environment with injection of lentivirus-mediated transfection of chondroitinase ABC gene at the rostral and caudal borders of the lesion site and simultaneously leveraging the repair capacity of transplanted Schwann cells in adult rats following a mid-thoracic contusive spinal cord injury.We report that when the glial scar was degraded by chondroitinase ABC at the rostral and caudal lesion borders,Schwann cells migrated for considerable distances in both rostral and caudal directions.Such Schwann cell migration led to enhanced axonal regrowth,including the serotonergic and dopaminergic axons originating from supraspinal regions,and promoted recovery of locomotor and urinary bladder functions.Importantly,the Schwann cell survival and axonal regrowth persisted up to 6 months after the injury,even when treatment was delayed for 3 months to mimic chronic spinal cord injury.These findings collectively show promising evidence for a combinatorial strategy with chondroitinase ABC and Schwann cells in promoting remodeling and recovery of function following spinal cord injury.

Effects of neural stem cell transplantation on the motor function of rats with contusion spinal cord injuries:a meta-analysis

Objective:To judge the efficacies of neural stem cell(NSC)transplantation on functional recovery following contusion spinal cord injuries(SCIs).Data sources:Studies in which NSCs were transplanted into a clinically relevant,standardized rat model of contusion SCI were identified by searching the PubMed,Embase and Cochrane databases,and the extracted data were analyzed by Stata 14.0.Data selection:Inclusion criteria were that NSCs were used in in vivo animal studies to treat contusion SCIs and that behavioral assessment of locomotor functional recovery was performed using the Basso,Beattie,and Bresnahan lo-comotor rating scale.Exclusion criteria included a follow-up of less than 4 weeks and the lack of control groups.Outcome measures:The restoration of motor function was assessed by the Basso,Beattie,and Bresnahan locomotor rating scale.Results:We identified 1756 non-duplicated papers by searching the aforementioned electronic databases,and 30 full-text articles met the inclusion criteria.A total of 37 studies reported in the 30 articles were included in the meta-analysis.The meta-analysis results showed that transplanted NSCs could improve the motor function recovery of rats following contusion SCIs,to a moderate extent(pooled standardized mean difference(SMD)=0.73;95%confidence interval(CI):0.47–1.00;P<0.001).NSCs obtained from different donor species(rat:SMD=0.74;95%CI:0.36–1.13;human:SMD=0.78;95%CI:0.31–1.25),at different donor ages(fetal:SMD=0.67;95%CI:0.43–0.92;adult:SMD=0.86;95%CI:0.50–1.22)and from different origins(brain-derived:SMD=0.59;95%CI:0.27–0.91;spinal cord-derived:SMD=0.51;95%CI:0.22–0.79)had similar efficacies on improved functional recovery;however,adult induced pluripotent stem cell-derived NSCs showed no significant efficacies.Furthermore,the use of higher doses of transplanted NSCs or the administration of immunosuppressive agents did not promote better locomotor function recovery(SMD=0.45;95%CI:0.21–0.70).However,shorter periods between the contusion induction and the NSC transplantation showed slightly higher efficacies(acute:SMD=1.22;95%CI:0.81–1.63;subacute:SMD=0.75;95%CI:0.42–1.09).For chronic injuries,NSC implantation did not significantly improve functional recovery(SMD=0.25;95%CI:–0.16 to 0.65).Conclusion:NSC transplantation alone appears to be a positive yet limited method for the treatment of contusion SCIs.

Liver preservation prior to transplantation: Past, present, and future

Since Dr. Thomas Starzl performed the first series of successful liver transplants(LTs), important advances have been made in immunosuppression, operative techniques, and postoperative care. In 1988, Belzer's group reported the first successful LT using the University of Wisconsin preservation solution(UW).Since then, UW has replaced EuroCollins solution and allowed prolonged and safer preservation of liver, kidney, and pancreas allografts, thus contributing to the improvement of transplant outcomes. Although UW is still considered the standard of care in the United States and in several countries worldwide, a recent meta-analysis revealed similar LT outcomes among UW, Celsior solution, and the Institut Georges Lopez-1 preservation solution, which were slightly superior to those obtained with histidine-tryptophan-ketoglutarate preservation solution.Dynamic preservation has been recently developed, and liver allografts are preserved mainly through the following methods: hypothermic machine perfusion, normothermic machine perfusion, and subnormothermic machine perfusion. Their use has the potential advantage of improving clinical results in LT involving extended criteria donor allografts. Although associated with increased costs, techniques employing machine perfusion of liver allografts have been considered clinically feasible. This editorial focuses on recent advances and future perspectives in liver allograft preservation.

Clinical outcome in patients with hepatocellular carcinoma after living-donor liver transplantation

AIM: To investigate risk factors for hepatocellular carcinoma (HCC) recurrence after living donor liver transplantation (LDLT) and efficacy of various criteria. METHODS: From October 2000 to November 2011, 233 adult patients underwent LDLT for HCC at our institution. After excluding nine postoperative mortality cases, we analyzed retrospectively 224 patients. To identify risk factors for recurrence, we evaluated recurrence, disease-free survival (DFS) rate, survival rate, and various other factors which are based on the characteristics of both the patient and tumor. Additionally, we developed our own criteria based on our data. Next, we compared our selection criteria with various tumor-grading scales, such as the Milan criteria, University of California, San Francisco (UCSF) criteria, TNM stage, Barcelona Clinic Liver Cancer (BCLC) stage and Cancer of the Liver Italian Program (CLIP) scoring system. The median follow up was 68 (6-139) mo.RESULTS: In 224 patients who received LDLT for HCC, 37 (16.5%) experienced tumor recurrence during the follow-up period. The 5-year DFS and overall survival rates after LDLT in all patients with HCC were 80.9% and 76.4%, respectively. On multivariate analysis, the tumor diameter {5 cm; P < 0.001; exponentiation of the B coefficient [Exp(B)], 11.89; 95%CI: 3.784-37.368} and alpha fetoprotein level [AFP, 100 ng/mL; P = 0.021; Exp(B), 2.892; 95%CI: 1.172-7.132] had significant influences on HCC recurrence after LDLT. Therefore, these two factors were included in our criteria. Based on these data, we set our selection criteria as a tumor diameter ≤ 5 cm and AFP ≤ 100 ng/mL. Within our new criteria (140/214, 65.4%), the 5-year DFS and overall survival rates were 88.6% and 81.8%, respectively. Our criteria (P = 0.001), Milan criteria (P = 0.009), and UCSF criteria (P = 0.001) showed a significant difference in DFS rate. And our criteria (P = 0.006) and UCSF criteria (P = 0.009) showed a significant difference in overall survival rate. But Milan criteria did not show significant difference in overall survival rate (P = 0.137). Among stages 0, A, B and C of BCLC, stage C had a significantly higher recurrence rate (P = 0.001), lower DFS (P = 0.001), and overall survival rate (P = 0.005) compared with the other stages. Using the CLIP scoring system, the group with a score of 4 to 5 showed a high recurrence rate (P = 0.023) and lower DFS (P = 0.011); however, the overall survival rate did not differ from that of the lower scoring group. The TNM system showed a trend of increased recurrence rate, decreased DFS, or survival rate according to T stage, albeit without statistical significance. CONCLUSION: LDLT is considered the preferred therapeutic option in patients with an AFP level less than 100 ng/mL and a tumor diameter of less than 5 cm.

De novo malignancies after liver transplantation: The effect of immunosuppression-personal data and review of literature

BACKGROUND Immunosuppression has undoubtedly raised the overall positive outcomes in the post-operative management of solid organ transplantation. However, long-term exposure to immunosuppression is associated with critical systemic morbidities. De novo malignancies following orthotopic liver transplants (OLTs) are a serious threat in pediatric and adult transplant individuals. Data from different experiences were reported and compared to assess the connection between immunosuppression and de novo malignancies in liver transplant patients. AIM To study the role of immunosuppression on the incidence of de novo malignancies in liver transplant recipients. METHODS A systematic literature examination about de novo malignancies and immunosuppression weaning in adult and pediatric OLT recipients was described in the present review. Worldwide data were collected from highly qualified institutions performing OLTs. Patient follow-up, immunosuppression discontinuation and incidence of de novo malignancies were reported. Likewise, the review assesses the differences in adult and pediatric recipients by describing the adopted immunosuppression regimens and the different type of diagnosed solid and blood malignancy.RESULTS Emerging evidence suggests that the liver is an immunologically privileged organ able to support immunosuppression discontinuation in carefully selected recipients. Malignancies are often detected in liver transplant patients undergoing daily immunosuppression regimens. Post-transplant lymphoproliferative diseases and skin tumors are the most detected de novo malignancies in the pediatric and adult OLT population, respectively. To date, immunosuppression withdrawal has been achieved in up to 40% and 60% of well-selected adult and pediatric recipients, respectively. In both populations, a clear benefit of immunosuppression weaning protocols on de novo malignancies is difficult to ascertain because data have not been specified in most of the clinical experiences. CONCLUSION The selected populations of tolerant pediatric and adult liver transplant recipients greatly benefit from immunosuppression weaning. There is still no strong clinical evidence on the usefulness of immunosuppression withdrawal in OLT recipients on malignancies. An interesting focus is represented by the complete reconstitution of the immunological pathways that could help in decreasing the incidence of de novo malignancies and may also help in treating liver transplant patients suffering from cancer.

Management of recurrent hepatocellular carcinoma after liver transplant

Hepatocellular carcinoma(HCC) is the leading cause of deaths in patients with hepatitis B or C, and its incidence has increased considerably over the past decade and is still on the rise. Liver transplantation(LT) provides the best chance of cure for patients with HCC and liver cirrhosis. With the implementation of the MELD exception system for patients with HCC waitlisted for LT, the number of recipients of LT is increasing, so is the number of patients who have recurrence of HCC after LT. Treatments for intrahepatic recurrence after transplantation and after other kinds of surgery are more or less the same, but long-term cure of posttransplant recurrence is rarely seen as it is a "systemic" disease. Nonetheless, surgicalresection has been shown to be effective in prolonging patient survival despite the technical difficulty in resecting graft livers. Besides surgical resection, different kinds of treatment are also in use, including transarterial chemoembolization, radiofrequency ablation, highintensity focused ultrasound ablation, and stereotactic body radiation therapy. Targeted therapy and modulation of immunosuppressants are also adopted to treat the deadly disease.

Genetic barriers in transplantation medicine

The successful of transplantation is determined by the shared human leukocyte antigens(HLAs) and ABO blood group antigens between donor and recipient. In recent years, killer cell receptor [i.e., killer cell immunoglobulinlike receptor(KIR)] and major histocompatibility complex(MHC) class I chain-related gene molecule(i.e., MICA) were also reported as important determinants of transplant compatibility. At present, several different genotyping techniques(e.g., sequence specific primer and sequence based typing) can be used to characterize blood group, HLA, MICA and KIR and loci. These molecular techniques have several advantages because they do not depend on the availability of anti-sera, cellular expression and have greater specificity and accuracy compared with the antibody-antigen based typing. Nonetheless, these molecular techniques have limited capability to capture increasing number of markers which have been demonstrated to determine donor and recipient compatibility. It is now possible to genotype multiple markers and to the extent of a complete sequencing of the human genome using next generation sequencer(NGS). This high throughput genotyping platform has been tested for HLA, and it is expected that NGS will be used to simultaneously genotype a large number of clinically relevant transplantation genes in near future. This is not far from reality due to the bioinformatics support given by the immunogenetics community and the rigorous improvement in NGS methodology. In addition, new developments in immune tolerance based therapy, donor recruitment strategies and bioengineering are expected to provide significant advances in the field of transplantation medicine.

Split liver transplantation:What's unique?

The intraoperative management of split liver transplantation(SLT) has some unique features as compared to routine whole liver transplantations. Only the liver has this special ability to regenerate that confers benefits in survival and quality of life for two instead of one by splitting livers. Primary graft dysfunction may result from small for size syndrome. Graft weight to recipient body weight ratio is significant for both trisegmental and hemiliver grafts. Intraoperative surgical techniques aim to reduce portal hyperperfusion and decrease venous portal pressure. Ischemic preconditioning can be instituted to protect against ischemic reperfusion injury which impacts graft regeneration. Advancement of the technique of SLT is essential as use of split cadaveric grafts expands the donor pool and potentially has an excellent future.

Is it time to give up with calcineurin inhibitors in kidney transplantation?

Calcineurin inhibitors(CNIs) represent today a cornerstone for the maintenance immunosuppressive treatment in solid organ transplantation. Nevertheless, several attempts have been made either to minimize their dosage or to avoid CNIs at all because these drugs have the severe side effect of chronic nephrotoxicity. This issue represents a frontier for renal transplantation. The principal problem is to understanding whether the poor outcome over the long-term may be ascribed to CNIs nephrotoxicity or to the inability of these drugs to control the acute and chronic rejection B cells mediated. The authors analyze extensively all the international trials attempting to withdraw, minimize or avoid the use of CNIs. Few trials undertaken in low risk patients with an early conversion from CNIs to proliferation signal inhibitors were successful, but the vast majority of trials failed to improve CNIs side effects. To date the use of a new drug, a co-stimulation blocker, seems promising in avoiding CNIs with similar efficacy, better glomerular filtration rate and an improved metabolic profile. Moreover the use of this drug is not associated with the development of donorspecific anti-human leukocyte antigen antibodies. Thispoint has a particular relevance, because the failure of CNIs to realize good outcomes in renal transplantation has recently ascribed to their inability to control the acute and chronic rejections B-cell mediated. This paper analyzes all the recent studies that have been done on this issue that represents the real frontier that should be overcome to realize better results over the long-term after transplantation.

Exercise after heart transplantation: An overview

While life expectancy is greatly improved after a heart transplant, survival is still limited, and compared to the general population, the exercise capacity and healthrelated quality of life of heart transplant recipients are reduced. Increased exercise capacity is associated with a better prognosis. However, although several studies have documented positive effects of exercise after heart transplantation(HTx), little is known about the type, frequency and intensity of exercise that provides the greatest health benefits. Moreover, the long-term effects of exercise on co-morbidities and survival are also unclear. Exercise restrictions apply to patients with a denervated heart, and for decades, it was believed that the transplanted heart remained denervated. This has since been largely disproved, but despite the new knowledge, the exercise restrictions have largely remained, and up-to-date guidelines on exercise prescription after HTx do not exist. High-intensity, interval based aerobic exercise has repeatedly been documented to have superior positive effects and health benefits compared to moderate exercise. This applies to both healthy subjects as well as in several patient groups, such as patients with metabolic syndrome, coronary artery disease or heart failure. However, whether the effects of this type of exercise are also applicable to heart transplant populations has not yet been full yestablished. The purpose of this article is to give an overview of the current knowledge about the exercise capacity and effect of exercise among heart transplant recipients and to discuss future exercise strategies.

Mild hypothermia combined with neural stem cell transplantation for hypoxic-ischemic encephalopathy: neuroprotective effects of combined therapy

Neural stem cell transplantation is a useful treatment for ischemic stroke, but apoptosis often occurs in the hypoxic-ischemic environment of the brain after cell transplantation. In this study, we determined if mild hypothermia （27-28~C） can increase the survival rate of neural stem cells （1.0 x 105/~tL） transplanted into neonatal mice with hypoxic-ischemic encephalopathy. Long-term effects on neurological functioning of the mice were also examined. After mild hy- pothermia combined with neural stem cell transplantation, we observed decreased expression levels of inflammatory factor nuclear factor-kappa B and apoptotic factor caspase-3, reduced cerebral infarct volumes, increased survival rate of transplanted cells, and marked improvements in neurological function. Thus, the neuroprotective effects of mild hypothermia combined with neural stem cell transplantation are superior to those of monotherapy. Moreover, our findings suggest that the neuroprotective effects of mild hypothermia combined with neural stem cell transplantation on hypoxic-ischemic encephalopathy are achieved by anti-inflammatory and an- ti-apoptotic mechanisms.

Feasibility of using marginal liver grafts in living donor liver transplantation

Liver transplantation(LT) is one of the most effective treatments for end-stage liver disease caused by related risk factors when liver resection is contraindicated. Additionally,despite the decrease in the prevalence of hepatitis B virus(HBV) over the past two decades,the absolute number of HBs Ag-positive people has increased,leading to an increase in HBV-related liver cirrhosis and hepatocellular carcinoma. Consequently,a large demand exists for LT. While the wait time for patients on the donor list is,to some degree,shorter due to the development of living donor liver transplantation(LDLT),there is still a shortage of liver grafts. Furthermore,recipients often suffer from emergent conditions,such as liver dysfunction or even hepatic encephalopathy,which can lead to a limited choice in grafts. To expand the pool of available liver grafts,one option is the use of organs that were previously considered "unusable" by many,which are often labeled "marginal" organs. Many previous studies have reported on the possibilities of using marginal grafts in orthotopic LT; however,there is still a lack of discussion on this topic,especially regarding the feasibility of using marginal grafts in LDLT. Therefore,the present review aimed to summarize the feasibility of using marginal liver grafts for LDLT and discuss the possibility of expanding the application of these grafts.

New model for cardiomyocyte sheet transplantation using a virus-cell fusion technique

AIM: To facilitate close contacts between transplanted cardiomyocytes and host skeletal muscle using cell fusion mediated by hemagglutinating virus of Japan envelope(HVJ-E) and tissue maceration. METHODS: Cardiomyocytes(1.5 × 106) from fetal rats were first cultured. After proliferation, some cells were used for fusion with adult muscle fibers using HVJ-E. Other cells were used to create cardiomyocyte sheets(area: about 3.5 cm2 including 2.1 × 106 cells), which were then treated with Nile blue, separated, and transplanted between the latissimus dorsi and intercostal muscles of adult rats with four combinations of HVJ-E and/or Na OH maceration: G1: HVJ-E(+), Na OH(+), Cardiomyocytes(+); G2: HVJ-E(-), NaO H(+), Cardiomyocytes(+); G3: HVJ-E(+),Na OH(-), Cardiomyocytes(+); G4: HVJ-E(-), Na OH(-), Cardiomyocytes(-). At 1 and 2 wk after transplantation, the four groups were compared by detection of beating domains, motion images using moving target analysis software, action potentials, gene expression of MLC-2v and Mesp1 by reverse transcription-polymerase chain reaction, hematoxylin-eosin staining, and immunostaining for cardiac troponin and skeletal myosin.RESULTS: In vitro cardiomyocytes were fused with skeletal muscle fibers using HVJ-E. Cardiomyocyte sheets remained in the primary transplanted sites for 2 wk. Although beating domains were detected in G1, G2, and G3 rats, G1 rats prevailed in the number, size, motion image amplitudes, and action potential compared with G2 and G3 rats. Close contacts were only found in G1 rats. At 1 wk after transplantation, the cardiomyocyte sheets showed adhesion at various points to the myoblast layer in the latissimus dorsi muscle. At 2 wk after transplantation, close contacts were seen over a broad area. Part of the skeletal muscle sarcoplasma seemed to project into the myocardiocyte plasma and some nuclei appeared to share both sarcoplasmas.CONCLUSION: The present results show that close contacts were acquired and facilitated the beating function, thereby providing a new cellular transplantation method using HVJ-E and NaO H maceration.

Importance of genetic polymorphisms in liver transplantation outcomes

Although,liver transplantation serves as the only curative treatment for patients with end-stage liver diseases,it is burdened with complications,which affect survival rates.In addition to clinical risk factors,contribution of recipient and donor genetic prognostic markers has been extensively studied in order to reduce the burden and improve the outcomes.Determination of single nucleotide polymorphisms(SNPs)is one of the most important tools in development of personalized transplant approach.To provide a better insight in recent developments,we review the studies published in the last three years that investigated an association of recipient or donor SNPs with most common issues in liver transplantation:Acute cellular rejection,development of new-onset diabetes mellitus and non-alcoholic fatty liver disease,hepatocellular carcinoma recurrence,and tacrolimus concentration variability.Reviewed studies confirmed previously established SNP prognostic factors,such as PNPLA3 rs738409 for nonalcoholic fatty liver disease development,or the role of CYP3A5 rs776746 in tacrolimus concentration variability.They also identified several novel SNPs,with a reasonably strong association,which have the potential to become useful predictors of post-transplant complications.However,as the studies were typically conducted in one center on relatively low-to-moderate number of patients,verification of the results in other centers is warranted to resolve these limitations.Furthermore,of 29 reviewed studies,28 used gene candidate approach and only one implemented a genome wide association approach.Genome wide association multicentric studies are needed to facilitate the development of personalized transplant medicine.

Zhichan decoction induces differentiation of dopaminergic neurons in Parkinson's disease rats after neural stem cell transplantation

The goal of this study was to increase the dopamine content and reduce dopaminergic metabolites in the brain of Parkinson’s disease rats. Using high-performance liquid chromatography, we found that dopamine and dopaminergic metabolite（dihydroxyphenylacetic acid and homovanillic acid） content in the midbrain of Parkinson’s disease rats was increased after neural stem cell transplantation ＋ Zhichan decoction, compared with neural stem cell transplantation alone. Our genetic algorithm results show that dihydroxyphenylacetic acid and homovanillic acid levels achieve global optimization. Neural stem cell transplantation ＋ Zhichan decoction increased dihydroxyphenylacetic acid levels up to 10-fold, while transplantation alone resulted in a 3-fold increment. Homovanillic acid levels showed no apparent change. Our experimental findings show that after neural stem cell transplantation in Parkinson’s disease rats, Zhichan decoction can promote differentiation of neural stem cells into dopaminergic neurons.

Hematopoietic stem cell transplantation for auto immune rheumatic diseases

Stem cells have their origins in the embryo and during the process of organogenesis, these differentiate into specialized cells which mature to form tissues. In addition, stem cell are characterized by an ability to indefinitely self renew. Stem cells are broadly classified into embryonic stem cells and adult stem cells. Adult stem cells can be genetically reprogrammed to form pluripotent stem cells and exist in an embroyonic like state. In the early phase of embryogenesis, human embryonic stem cells only exist transiently. Adult stem cells are omnipresent in the body and function to regenerate during the process of apoptosis or tissue repair. Hematopoietic stem cells(HSC) are adult stem cells that form blood and immune cells. Autoimmune responses are sustained due to the perennial persistence of tissue self autoantigens and/or auto reactive lymphocytes. Immune reset is a process leading to generation of fresh self-tolerant lymphocytes after chemotherapy induced elimination of self or autoreactive lymphocytes. This forms the basis for autologous HSC transplantation(HSCT). In the beginning HSCT had been limited to refractory autoimmune rheumatic diseases(AIRD) due to concern about transplant related mortality and morbidity. However HSCT for AIRD has come a long way with better understanding of patient selection, conditioning regime and supportive care. In this narrative review we have examined the available literature regarding the HSCT use in AIRD.