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Showing papers on "Transplantation published in 2009"


Journal ArticleDOI
TL;DR: Treatment with a continuous-flow left ventricular assist device in patients with advanced heart failure significantly improved the probability of survival free from stroke and device failure at 2 years as compared with a pulsatile device.
Abstract: Background Patients with advanced heart failure have improved survival rates and quality of life when treated with implanted pulsatile-flow left ventricular assist devices as compared with medical therapy. New continuous-flow devices are smaller and may be more durable than the pulsatile-flow devices. Methods In this randomized trial, we enrolled patients with advanced heart failure who were ineligible for transplantation, in a 2:1 ratio, to undergo implantation of a continuousflow device (134 patients) or the currently approved pulsatile-flow device (66 patients). The primary composite end point was, at 2 years, survival free from disabling stroke and reoperation to repair or replace the device. Secondary end points included survival, frequency of adverse events, the quality of life, and functional capacity. Results Preoperative characteristics were similar in the two treatment groups, with a median age of 64 years (range, 26 to 81), a mean left ventricular ejection fraction of 17%, and nearly 80% of patients receiving intravenous inotropic agents. The primary composite end point was achieved in more patients with continuous-flow devices than with pulsatile-flow devices (62 of 134 [46%] vs. 7 of 66 [11%]; P<0.001; hazard ratio, 0.38; 95% confidence interval, 0.27 to 0.54; P<0.001), and patients with continuous-flow devices had superior actuarial survival rates at 2 years (58% vs. 24%, P = 0.008). Adverse events and device replacements were less frequent in patients with the continuous-flow device. The quality of life and functional capacity improved significantly in both groups. Conclusions Treatment with a continuous-flow left ventricular assist device in patients with advanced heart failure significantly improved the probability of survival free from stroke and device failure at 2 years as compared with a pulsatile device. Both devices significantly improved the quality of life and functional capacity. (ClinicalTrials.gov number, NCT00121485.)

2,796 citations


Journal ArticleDOI
TL;DR: A translational medicine pipeline is described where human gut microbial communities and diets are re-created in gnotobiotic mice and the impact on microbe and host is defined using metagenomics, creating a well-defined, representative animal model of the human gut ecosystem.
Abstract: Diet and nutritional status are among the most important modifiable determinants of human health. The nutritional value of food is influenced in part by a person's gut microbial community (microbiota) and its component genes (microbiome). Unraveling the interrelations among diet, the structure and operations of the gut microbiota, and nutrient and energy harvest is confounded by variations in human environmental exposures, microbial ecology, and genotype. To help overcome these problems, we created a well-defined, representative animal model of the human gut ecosystem by transplanting fresh or frozen adult human fecal microbial communities into germ-free C57BL/6J mice. Culture-independent metagenomic analysis of the temporal, spatial, and intergenerational patterns of bacterial colonization showed that these humanized mice were stably and heritably colonized and reproduced much of the bacterial diversity of the donor's microbiota. Switching from a low-fat, plant polysaccharide-rich diet to a high-fat, high-sugar "Western" diet shifted the structure of the microbiota within a single day, changed the representation of metabolic pathways in the microbiome, and altered microbiome gene expression. Reciprocal transplants involving various combinations of donor and recipient diets revealed that colonization history influences the initial structure of the microbial community but that these effects can be rapidly altered by diet. Humanized mice fed the Western diet have increased adiposity; this trait is transmissible via microbiota transplantation. Humanized gnotobiotic mice will be useful for conducting proof-of-principle "clinical trials" that test the effects of environmental and genetic factors on the gut microbiota and host physiology. Nearly full-length 16S rRNA gene sequences are deposited in GenBank under the accession numbers GQ491120 to GQ493997.

2,709 citations


Journal ArticleDOI
08 May 2009-Science
TL;DR: Results demonstrate that reprograming human somatic cells does not require genomic integration or the continued presence of exogenous reprogramming factors and removes one obstacle to the clinical application of human iPS cells.
Abstract: Reprogramming differentiated human cells to induced pluripotent stem (iPS) cells has applications in basic biology, drug development, and transplantation. Human iPS cell derivation previously required vectors that integrate into the genome, which can create mutations and limit the utility of the cells in both research and clinical applications. We describe the derivation of human iPS cells with the use of nonintegrating episomal vectors. After removal of the episome, iPS cells completely free of vector and transgene sequences are derived that are similar to human embryonic stem (ES) cells in proliferative and developmental potential. These results demonstrate that reprogramming human somatic cells does not require genomic integration or the continued presence of exogenous reprogramming factors and removes one obstacle to the clinical application of human iPS cells.

2,425 citations


Journal ArticleDOI
TL;DR: The understanding of the risk factors and causes of GHVD, the cellular and cytokine networks implicated in its pathophysiology, and current strategies to prevent and treat the disease are reviewed.

2,083 citations


Journal ArticleDOI
TL;DR: Stem cells from a donor who was homozygous for CCR5 delta32 were transplanted in a patient with acute myeloid leukemia and HIV-1 infection and the patient remained without viral rebound 20 months after transplantation and discontinuation of antiretroviral therapy.
Abstract: Infection with the human immunodeficiency virus type 1 (HIV-1) requires the presence of a CD4 receptor and a chemokine receptor, principally chemokine receptor 5 (CCR5). Homozygosity for a 32-bp deletion in the CCR5 allele provides resistance against HIV-1 acquisition. We transplanted stem cells from a donor who was homozygous for CCR5 delta32 in a patient with acute myeloid leukemia and HIV-1 infection. The patient remained without viral rebound 20 months after transplantation and discontinuation of antiretroviral therapy. This outcome demonstrates the critical role CCR5 plays in maintaining HIV-1 infection.

1,657 citations


Journal ArticleDOI
TL;DR: More patients with hepatocellular carcinoma could be candidates for transplantation if the current dual approach to candidacy, based on the strict Milan criteria, were replaced with a more precise estimation of survival contouring individual tumour characteristics and use of the up-to-seven criteria.
Abstract: Summary Background Patients undergoing liver transplantation for hepatocellular carcinoma within the Milan criteria (single tumour ≤5 cm in size or ≤3 tumours each ≤3 cm in size, and no macrovascular invasion) have an excellent outcome. However, survival for patients with cancers that exceed these criteria remains unpredictable and access to transplantation is a balance of maximising patients' chances of cure and organ availability. The aim of this study was to explore the survival of patients with tumours that exceed the Milan criteria, to assess whether the criteria could be less restrictive, enabling more patients to qualify as transplant candidates, and to derive a prognostic model based on objective tumour characteristics, to see whether the Milan criteria could be expanded. Methods Data on patients who underwent transplantation for hepatocellular carcinoma despite exceeding Milan criteria at different centres were recorded via a web-based survey completed by specialists from each centre. The survival of these patients was correlated retrospectively with the size of the largest tumour nodule, number of nodules, and presence or absence of microvascular invasion detected at pathology. Contoured multivariable regression Cox models produced survival estimates by means of different combinations of the covariates. The primary aim of this study was to derive a prognostic model of overall survival based on tumour characteristics, according to the main parameters used in the Tumour Node Metastasis classification. The secondary aim was the identification of a subgroup of patients with hepatocellular carcinoma exceeding the Milan criteria, who achieved a 5-year overall survival of at least 70%—ie, similar to the outcome expected for patients who meet the Milan criteria. Findings Over a 10-month period, between June 25, 2006, and April 3, 2007, data for 1556 patients who underwent transplantation for hepatocellular carcinoma were entered on the database by 36 centres. 1112 patients had hepatocellular carcinoma exceeding Milan criteria and 444 patients had hepatocellular carcinoma shown not to exceed Milan criteria at post-transplant pathology review. In the group of patients with hepatocellular carcinomas exceeding the criteria, the median size of the largest nodule was 40 mm (range 4–200) and the median number of nodules was four (1–20). 454 of 1112 patients (41%) had microvascular invasion and, for those transplanted outside the Milan criteria, 5-year overall survival was 53·6% (95% CI 50·1–57·0), compared with 73·3% (68·2–77·7) for those that met the criteria. Hazard ratios (HR) associated with increasing values of size and number were 1·34 (1·25–1·44) and 1·51 (1·21–1·88), respectively. The effect was linear for size, whereas for number of tumours, the effect tended to plateau above three tumours. The effect of tumour size and number on survival was mediated by recurrence (b=0·08, SE=0·12, p=0·476). The presence of microvascular invasion doubled HRs in all scenarios. The 283 patients without microvascular invasion, but who fell within the Up-to-seven criteria (hepatocellular carcinomas with seven as the sum of the size of the largest tumour [in cm] and the number of tumours) achieved a 5-year overall survival of 71·2% (64·3–77·0). Interpretation More patients with hepatocellular carcinoma could be candidates for transplantation if the current dual (yes/no) approach to candidacy, based on the strict Milan criteria, were replaced with a more precise estimation of survival contouring individual tumour characteristics and use of the up-to-seven criteria. Funding Specific funding was not used to do this study.

1,547 citations


Journal ArticleDOI
TL;DR: The results suggest that viral eradication might be achieved through the combined use of strategic interventions targeting viral replication and drugs that interfere with the self renewal and persistence of proliferating memory T cells.
Abstract: HIV persists in a reservoir of latently infected CD4+ T cells in individuals treated with highly active antiretroviral therapy (HAART). Here we identify central memory (TCM) and transitional memory (TTM) CD4+ T cells as the major cellular reservoirs for HIV and find that viral persistence is ensured by two different mechanisms. HIV primarily persists in TCM cells in subjects showing reconstitution of the CD4+ compartment upon HAART. This reservoir is maintained through T cell survival and low-level antigen-driven proliferation and is slowly depleted with time. In contrast, proviral DNA is preferentially detected in TTM cells from aviremic individuals with low CD4+ counts and higher amounts of interleukin-7–mediated homeostatic proliferation, a mechanism that ensures the persistence of these cells. Our results suggest that viral eradication might be achieved through the combined use of strategic interventions targeting viral replication and, as in cancer, drugs that interfere with the self renewal and persistence of proliferating memory T cells.

1,517 citations


Journal ArticleDOI
TL;DR: Changes include the recommendations for PCV rather than PPSV-23 for pneumococcal vaccination, starting some vaccinations earlier post-transplant, and the addition of recommendations for Varivax, HPV vaccine, and (the non-use of) Zostavax vaccine are included.

1,434 citations


Journal ArticleDOI
06 Nov 2009-Science
TL;DR: Lentiviral-mediated gene therapy of hematopoietic stem cells can provide clinical benefits in ALD, and progressive cerebral demyelination in the two patients stopped, a clinical outcome comparable to that achieved by allogeneic HCT.
Abstract: X-linked adrenoleukodystrophy (ALD) is a severe brain demyelinating disease in boys that is caused by a deficiency in ALD protein, an adenosine triphosphate–binding cassette transporter encoded by the ABCD1 gene. ALD progression can be halted by allogeneic hematopoietic cell transplantation (HCT). We initiated a gene therapy trial in two ALD patients for whom there were no matched donors. Autologous CD34 + cells were removed from the patients, genetically corrected ex vivo with a lentiviral vector encoding wild-type ABCD1 , and then re-infused into the patients after they had received myeloablative treatment. Over a span of 24 to 30 months of follow-up, we detected polyclonal reconstitution, with 9 to 14% of granulocytes, monocytes, and T and B lymphocytes expressing the ALD protein. These results strongly suggest that hematopoietic stem cells were transduced in the patients. Beginning 14 to 16 months after infusion of the genetically corrected cells, progressive cerebral demyelination in the two patients stopped, a clinical outcome comparable to that achieved by allogeneic HCT. Thus, lentiviral-mediated gene therapy of hematopoietic stem cells can provide clinical benefits in ALD.

1,378 citations


Journal ArticleDOI
TL;DR: Mutations in genes encoding the IL10R subunit proteins were found in patients with early-onset enterocolitis, involving hyperinflammatory immune responses in the intestine, and resulted in disease remission in one patient.
Abstract: Background The molecular cause of inflammatory bowel disease is largely unknown. Methods We performed genetic-linkage analysis and candidate-gene sequencing on samples from two unrelated consanguineous families with children who were affected by early-onset inflammatory bowel disease. We screened six additional patients with early-onset colitis for mutations in two candidate genes and carried out functional assays in patients' peripheral-blood mononuclear cells. We performed an allogeneic hematopoietic stem-cell transplantation in one patient. Results In four of nine patients with early-onset colitis, we identified three distinct homozygous mutations in genes IL10RA and IL10RB, encoding the IL10R1 and IL10R2 proteins, respectively, which form a heterotetramer to make up the interleukin-10 receptor. The mutations abrogate interleukin-10–induced signaling, as shown by deficient STAT3 (signal transducer and activator of transcription 3) phosphorylation on stimulation with interleukin-10. Consistent with this...

1,269 citations


Journal ArticleDOI
TL;DR: The authors critically review the current evidence relating systemic blood levels of cyclosporine and tacrolimus to calcineurin inhibitor nephrotoxicity, and summarize the data suggesting that local exposure to cycloporine or tacolimus could be more important than systemic exposure.
Abstract: The use of the calcineurin inhibitors cyclosporine and tacrolimus led to major advances in the field of transplantation, with excellent short-term outcome. However, the chronic nephrotoxicity of these drugs is the Achilles' heel of current immunosuppressive regimens. In this review, the authors summarize the clinical features and histologic appearance of both acute and chronic calcineurin inhibitor nephrotoxicity in renal and nonrenal transplantation, together with the pitfalls in its diagnosis. The authors also review the available literature on the physiologic and molecular mechanisms underlying acute and chronic calcineurin inhibitor nephrotoxicity, and demonstrate that its development is related to both reversible alterations and irreversible damage to all compartments of the kidneys, including glomeruli, arterioles, and tubulo-interstitium. The main question--whether nephrotoxicity is secondary to the actions of cyclosporine and tacrolimus on the calcineurin-NFAT pathway--remains largely unanswered. The authors critically review the current evidence relating systemic blood levels of cyclosporine and tacrolimus to calcineurin inhibitor nephrotoxicity, and summarize the data suggesting that local exposure to cyclosporine or tacrolimus could be more important than systemic exposure. Finally, other local susceptibility factors for calcineurin inhibitor nephrotoxicity are reviewed, including variability in P-glycoprotein and CYP3A4/5 expression or activity, older kidney age, salt depletion, the use of nonsteroidal anti-inflammatory drugs, and genetic polymorphisms in genes like TGF-beta and ACE. Better insight into the mechanisms underlying calcineurin inhibitor nephrotoxicity might pave the way toward more targeted therapy or prevention of calcineurin inhibitor nephrotoxicity.

Journal ArticleDOI
05 Nov 2009-Blood
TL;DR: A novel experimental and computational approach is developed to measure TCR CDR3 diversity based on single-molecule DNA sequencing, and it is found that total TCRbeta receptor diversity is at least 4-fold higher than previous estimates, and the diversity in the subset of CD45RO(+) antigen-experienced alphabeta T cells is at at least 10-foldHigher than previously estimates.

Journal ArticleDOI
09 Jul 2009-Nature
TL;DR: In lipoatrophic A-ZIP/F1 ‘fatless’ mice, and in mice treated with the peroxisome proliferator-activated receptor-γ inhibitor bisphenol A diglycidyl ether, marrow engraftment after irradiation is accelerated relative to wild-type or untreated mice, suggesting that antagonizing marrow adipogenesis may enhance haematopoietic recovery in clinical bone-marrow transplantation.
Abstract: Osteoblasts and endothelium constitute functional niches that support haematopoietic stem cells in mammalian bone marrow. Adult bone marrow also contains adipocytes, the number of which correlates inversely with the haematopoietic activity of the marrow. Fatty infiltration of haematopoietic red marrow follows irradiation or chemotherapy and is a diagnostic feature in biopsies from patients with marrow aplasia. To explore whether adipocytes influence haematopoiesis or simply fill marrow space, we compared the haematopoietic activity of distinct regions of the mouse skeleton that differ in adiposity. Here we show, by flow cytometry, colony-forming activity and competitive repopulation assay, that haematopoietic stem cells and short-term progenitors are reduced in frequency in the adipocyte-rich vertebrae of the mouse tail relative to the adipocyte-free vertebrae of the thorax. In lipoatrophic A-ZIP/F1 'fatless' mice, which are genetically incapable of forming adipocytes, and in mice treated with the peroxisome proliferator-activated receptor-gamma inhibitor bisphenol A diglycidyl ether, which inhibits adipogenesis, marrow engraftment after irradiation is accelerated relative to wild-type or untreated mice. These data implicate adipocytes as predominantly negative regulators of the bone-marrow microenvironment, and indicate that antagonizing marrow adipogenesis may enhance haematopoietic recovery in clinical bone-marrow transplantation.

Journal ArticleDOI
TL;DR: Hypothermic machine perfusion was associated with a reduced risk of delayed graft function and improved graft survival in the first year after transplantation.
Abstract: BACKGROUND Static cold storage is generally used to preserve kidney allografts from deceased donors. Hypothermic machine perfusion may improve outcomes after transplantation, but few sufficiently powered prospective studies have addressed this possibility. METHODS In this international randomized, controlled trial, we randomly assigned one kidney from 336 consecutive deceased donors to machine perfusion and the other to cold storage. All 672 recipients were followed for 1 year. The primary end point was delayed graft function (requiring dialysis in the first week after transplantation). Secondary end points were the duration of delayed graft function, delayed graft function defined by the rate of the decrease in the serum creatinine level, primary nonfunction, the serum creatinine level and clearance, acute rejection, toxicity of the calcineurin inhibitor, the length of hospital stay, and allograft and patient survival. RESULTS Machine perfusion significantly reduced the risk of delayed graft function. Delayed graft function developed in 70 patients in the machine-perfusion group versus 89 in the cold-storage group (adjusted odds ratio, 0.57; P = 0.01). Machine perfusion also significantly improved the rate of the decrease in the serum creatinine level and reduced the duration of delayed graft function. Machine perfusion was associated with lower serum creatinine levels during the first 2 weeks after transplantation and a reduced risk of graft failure (hazard ratio, 0.52; P = 0.03). One-year allograft survival was superior in the machine-perfusion group (94% vs. 90%, P = 0.04). No significant differences were observed for the other secondary end points. No serious adverse events were directly attributable to machine perfusion. CONCLUSIONS Hypothermic machine perfusion was associated with a reduced risk of delayed graft function and improved graft survival in the first year after transplantation. (Current Controlled Trials number, ISRCTN83876362.)

Journal ArticleDOI
TL;DR: The epidemiology and choice of therapy for candidemia are rapidly changing and additional study is warranted to differentiate host factors and differences in virulence among Candida species and to determine the best therapeutic regimen.
Abstract: Background. Candidemia remains a major cause of morbidity and mortality in the health care setting, and the epidemiology of Candida infection is changing. Methods. Clinical data from patients with candidemia were extracted from the Prospective Antifungal Therapy (PATH) Alliance database, a comprehensive registry that collects information regarding invasive fungal infections. A total of 2019 patients, enrolled from 1 July 2004 through 5 March 2008, were identified. Data regarding the candidemia episode were analyzed, including the specific fungal species and patient survival at 12 weeks after diagnosis. Results. The incidence of candidemia caused by non-Candida albicans Candida species (54.4%) was higher than the incidence of candidemia caused by C. albicans (45.6%). The overall, crude 12-week mortality rate was 35.2%. Patients with Candida parapsilosis candidemia had the lowest mortality rate (23.7%; P<.001) and were less likely to be neutropenic (5.1%; P<.001) and to receive corticosteroids (33.5%; P<.001) or other immunosuppressive drugs (7.9%; P = .002), compared with patients infected with other Candida species. Candida krusei candidemia was most commonly associated with prior use of antifungal agents (70.6%; P<.001), hematologic malignancy (52.9%; P<.001) or stem cell transplantation (17.7%; P<.001), neutropenia (45.1%; P<.001), and corticosteroid treatment (60.8%; P<.001). Patients with C. krusei candidemia had the highest crude 12-week mortality in this series (52.9%; P<.001). Fluconazole was the most commonly administered antimicrobial, followed by the echinocandins, and amphotericin B products were infrequently administered. Conclusions. The epidemiology and choice of therapy for candidemia are rapidly changing. Additional study is warranted to differentiate host factors and differences in virulence among Candida species and to determine the best therapeutic regimen.

Journal ArticleDOI
TL;DR: A consensus group of experts comprised of experts in pediatric and adult endocrinology, diabetes education, transplantation, metabolism, bariatric/metabolic surgery, and (for another perspective) hematology-oncology met in June 2009 to discuss issues.
Abstract: The mission of the American Diabetes Association is “to prevent and cure diabetes and to improve the lives of all people affected by diabetes.” Increasingly, scientific and medical articles (1) and commentaries (2) about diabetes interventions use the terms “remission” and “cure” as possible outcomes. Several approved or experimental treatments for type 1 and type 2 diabetes (e.g., pancreas or islet transplants, immunomodulation, bariatric/metabolic surgery) are of curative intent or have been portrayed in the media as a possible cure. However, defining remission or cure of diabetes is not as straightforward as it may seem. Unlike “dichotomous” diseases such as many malignancies, diabetes is defined by hyperglycemia, which exists on a continuum and may be impacted over a short time frame by everyday treatment or events (medications, diet, activity, intercurrent illness). The distinction between successful treatment and cure is blurred in the case of diabetes. Presumably improved or normalized glycemia must be part of the definition of remission or cure. Glycemic measures below diagnostic cut points for diabetes can occur with ongoing medications (e.g., antihyperglycemic drugs, immunosuppressive medications after a transplant), major efforts at lifestyle change, a history of bariatric/metabolic surgery, or ongoing procedures (such as repeated replacements of endoluminal devices). Do we use the terms remission or cure for all patients with normal glycemic measures, regardless of how this is achieved? A consensus group comprised of experts in pediatric and adult endocrinology, diabetes education, transplantation, metabolism, bariatric/metabolic surgery, and (for another perspective) hematology-oncology met in June 2009 to discuss these issues. The group considered a wide variety of questions, including whether it is ever accurate to say that a chronic illness is cured; what the definitions of management, remission, or cure might be; whether goals of managing comorbid conditions revert to those of patients without diabetes if someone is …


Journal ArticleDOI
TL;DR: The newly developed transposase yields unprecedented stable gene transfer efficiencies following nonviral gene delivery that compare favorably to stable transduction efficiencies with integrating viral vectors and is expected to facilitate widespread applications in functional genomics and gene therapy.
Abstract: The Sleeping Beauty (SB) transposon is a promising technology platform for gene transfer in vertebrates; however, its efficiency of gene insertion can be a bottleneck in primary cell types. A large-scale genetic screen in mammalian cells yielded a hyperactive transposase (SB100X) with approximately 100-fold enhancement in efficiency when compared to the first-generation transposase. SB100X supported 35-50% stable gene transfer in human CD34(+) cells enriched in hematopoietic stem or progenitor cells. Transplantation of gene-marked CD34(+) cells in immunodeficient mice resulted in long-term engraftment and hematopoietic reconstitution. In addition, SB100X supported sustained (>1 year) expression of physiological levels of factor IX upon transposition in the mouse liver in vivo. Finally, SB100X reproducibly resulted in 45% stable transgenesis frequencies by pronuclear microinjection into mouse zygotes. The newly developed transposase yields unprecedented stable gene transfer efficiencies following nonviral gene delivery that compare favorably to stable transduction efficiencies with integrating viral vectors and is expected to facilitate widespread applications in functional genomics and gene therapy.

Journal ArticleDOI
TL;DR: Interestingly, despite widespread and established Aß plaque and neurofibrillary tangle pathology, hippocampal neural stem cell transplantation rescues the spatial learning and memory deficits in aged 3xTg-AD mice.
Abstract: Neural stem cell (NSC) transplantation represents an unexplored approach for treating neurodegenerative disorders associated with cognitive decline such as Alzheimer disease (AD). Here, we used aged triple transgenic mice (3xTg-AD) that express pathogenic forms of amyloid precursor protein, presenilin, and tau to investigate the effect of neural stem cell transplantation on AD-related neuropathology and cognitive dysfunction. Interestingly, despite widespread and established As plaque and neurofibrillary tangle pathology, hippocampal neural stem cell transplantation rescues the spatial learning and memory deficits in aged 3xTg-AD mice. Remarkably, cognitive function is improved without altering As or tau pathology. Instead, the mechanism underlying the improved cognition involves a robust enhancement of hippocampal synaptic density, mediated by brain-derived neurotrophic factor (BDNF). Gain-of-function studies show that recombinant BDNF mimics the beneficial effects of NSC transplantation. Furthermore, loss-of-function studies show that depletion of NSC-derived BDNF fails to improve cognition or restore hippocampal synaptic density. Taken together, our findings demonstrate that neural stem cells can ameliorate complex behavioral deficits associated with widespread Alzheimer disease pathology via BDNF.

Journal ArticleDOI
10 Jun 2009-JAMA
TL;DR: Compared with nonallogeneic SCT therapies, allogeneicSCT has significant RFS and overall survival benefit for intermediate- and poor-risk AML but not for good- risk AML in first complete remission.
Abstract: Context The optimal treatment of acute myeloid leukemia (AML) in first complete remission (CR1) is uncertain. Current consensus, based on cytogenetic risk, recommends myeloablative allogeneic stem cell transplantation (SCT) for poor-risk but not for good-risk AML. Allogeneic SCT, autologous transplantation, and consolidation chemotherapy are considered of equivalent benefit for intermediate-risk AML. Objective To quantify relapse-free survival (RFS) and overall survival benefit of allogeneic SCT for AML in CR1 overall and also for good-, intermediate-, and poor-risk AML. Methods Systematic review and meta-analysis of prospective trials evaluating allogeneic SCT vs nonallogeneic SCT therapies for AML in CR1. The search used the combined search terms allogeneic; acut* and leukem*/leukaem*/leucem*/leucaem*/aml; myelo* or nonlympho* in the PubMed, Embase, and Cochrane Registry of Controlled Trials databases in March 2009. The search identified 1712 articles. Study Selection Prospective trials assigning adult patients with AML in CR1 to undergo allogeneic SCT vs nonallogeneic SCT treatment(s) based on donor availability and trials reporting RFS and/or overall survival outcomes on an intention-to-treat, donor vs no-donor basis were identified. Data Extraction Two reviewers independently extracted study characteristics, interventions, and outcomes. Hazard ratios (HRs) with 95% confidence intervals (CIs) were determined. Data Synthesis Overall, 24 trials and 6007 patients were analyzed (5951 patients in RFS analyses and 5606 patients in overall survival analyses); 3638 patients were analyzed by cytogenetic risk (547, 2499, and 592 with good-, intermediate-, and poor-risk AML, respectively). Interstudy heterogeneity was not significant. Fixed-effects meta-analysis was performed. Compared with nonallogeneic SCT, the HR of relapse or death with allogeneic SCT for AML in CR1 was 0.80 (95% CI, 0.74-0.86). Significant RFS benefit of allogeneic SCT was documented for poor-risk (HR, 0.69; 95% CI, 0.57-0.84) and intermediate-risk AML (HR, 0.76; 95% CI, 0.68-0.85) but not for good-risk AML (HR, 1.06; 95% CI, 0.80-1.42). The HR of death with allogeneic SCT for AML in CR1 was 0.90 (95% CI, 0.82-0.97). Significant overall survival benefit with allogeneic SCT was documented for poor-risk (HR, 0.73; 95% CI, 0.59-0.90) and intermediate-risk AML (HR, 0.83; 95% CI, 0.74-0.93) but not for good-risk AML (HR, 1.07; 95% CI, 0.83-1.38). Conclusion Compared with nonallogeneic SCT therapies, allogeneic SCT has significant RFS and overall survival benefit for intermediate- and poor-risk AML but not for good-risk AML in first complete remission.

Journal ArticleDOI
TL;DR: In young adults with AML, intensifying induction therapy with a high daily dose of daunorubicin improved the rate of complete remission and the duration of overall survival, as compared with the standard dose.
Abstract: Background In young adults with acute myeloid leukemia (AML), intensification of the anthracycline dose during induction therapy has improved the rate of complete remission but not of overall survival. We evaluated the use of cytarabine plus either standard-dose or high-dose daunorubicin as induction therapy, followed by intensive consolidation therapy, in inducing complete remission to improve overall survival. Methods In this phase 3 randomized trial, we assigned 657 patients between the ages of 17 and 60 years who had untreated AML to receive three once-daily doses of daunorubicin at either the standard dose (45 mg per square meter of body-surface area) or a high dose (90 mg per square meter), combined with seven daily doses of cytarabine (100 mg per square meter) by continuous intravenous infusion. Patients who had a complete remission were offered either allogeneic hematopoietic stem-cell transplantation or high-dose cytarabine, with or without a single dose of the monoclonal antibody gemtuzumab ozog...

Journal ArticleDOI
TL;DR: This study used phenotypic, morphological, and functional criteria to identify and prospectively isolate a subset of MSCs (PDGFRα+Sca-1+CD45−TER119−) from adult mouse bone marrow and provided the useful method needed to identify M SCs as defined in vivo entities.
Abstract: Mesenchymal stem cells (MSCs) are defined as cells that undergo sustained in vitro growth and can give rise to multiple mesenchymal lineages. Because MSCs have only been isolated from tissue in culture, the equivalent cells have not been identified in vivo and little is known about their physiological roles or even their exact tissue location. In this study, we used phenotypic, morphological, and functional criteria to identify and prospectively isolate a subset of MSCs (PDGFRα+Sca-1+CD45−TER119−) from adult mouse bone marrow. Individual MSCs generated colonies at a high frequency and could differentiate into hematopoietic niche cells, osteoblasts, and adipocytes after in vivo transplantation. Naive MSCs resided in the perivascular region in a quiescent state. This study provides the useful method needed to identify MSCs as defined in vivo entities.


Journal ArticleDOI
TL;DR: Targets for investigation and intervention are identified that may result in improved kidney transplantation outcomes and alloinmunity remains the most common mechanism leading to failure.

Journal ArticleDOI
TL;DR: This work introduces optical frequency domain imaging (OFDI) as an intravital microscopy that circumvents the technical limitations of multiphoton microscopy and provides unprecedented access to previously unexplored, crucial aspects of tissue biology.
Abstract: Intravital multiphoton microscopy has provided powerful mechanistic insights into health and disease and has become a common instrument in the modern biological laboratory. The requisite high numerical aperture and exogenous contrast agents that enable multiphoton microscopy, however, limit the ability to investigate substantial tissue volumes or to probe dynamic changes repeatedly over prolonged periods. Here we introduce optical frequency domain imaging (OFDI) as an intravital microscopy that circumvents the technical limitations of multiphoton microscopy and, as a result, provides unprecedented access to previously unexplored, crucial aspects of tissue biology. Using unique OFDI-based approaches and entirely intrinsic mechanisms of contrast, we present rapid and repeated measurements of tumor angiogenesis, lymphangiogenesis, tissue viability and both vascular and cellular responses to therapy, thereby demonstrating the potential of OFDI to facilitate the exploration of physiological and pathological processes and the evaluation of treatment strategies.


Journal ArticleDOI
TL;DR: In this article, a new array-based method allowed screening of genome-wide copy number and loss of heterozygosity in single cells, which revealed not only mosaicism for whole-chromosome aneuploidies and uniparental disomies in most cleavage-stage embryos but also frequent segmental deletions, duplications and amplifications that were reciprocal in sister blastomeres, implying the occurrence of breakage-fusion-bridge cycles.
Abstract: Chromosome instability is a hallmark of tumorigenesis. This study establishes that chromosome instability is also common during early human embryogenesis. A new array-based method allowed screening of genome-wide copy number and loss of heterozygosity in single cells. This revealed not only mosaicism for whole-chromosome aneuploidies and uniparental disomies in most cleavage-stage embryos but also frequent segmental deletions, duplications and amplifications that were reciprocal in sister blastomeres, implying the occurrence of breakage-fusion-bridge cycles. This explains the low human fecundity and identifies post-zygotic chromosome instability as a leading cause of constitutional chromosomal disorders.

Journal ArticleDOI
20 Mar 2009-Cell
TL;DR: It is shown that wnt reporter activity in zebrafish HSCs is responsive to PGE2 modulation, demonstrating a direct interaction in vivo and suggesting the P GE2/Wnt interaction is a master regulator of vertebrate regeneration and recovery.

Journal ArticleDOI
TL;DR: Although HCT professionals have not reached a consensus on what constitutes a RIC regimen, most accept currently used criteria and operational definitions, and these results support the continued use of current criteria for RIC regimens until a consensus statement can be developed.

Journal ArticleDOI
27 Aug 2009-Nature
TL;DR: It is shown that PRDM16 forms a transcriptional complex with the active form of C/EBP-β (also known as LAP), acting as a critical molecular unit that controls the cell fate switch from myoblastic precursors to brown fat cells.
Abstract: Brown adipose cells are specialized to dissipate chemical energy in the form of heat, as a physiological defence against cold and obesity. PRDM16 (PR domain containing 16) is a 140 kDa zinc finger protein that robustly induces brown fat determination and differentiation. Recent data suggests that brown fat cells arise in vivo from a Myf5-positive, myoblastic lineage by the action of PRDM16 (ref. 3); however, the molecular mechanisms responsible for this developmental switch is unclear. Here we show that PRDM16 forms a transcriptional complex with the active form of C/EBP-beta (also known as LAP), acting as a critical molecular unit that controls the cell fate switch from myoblastic precursors to brown fat cells. Forced expression of PRDM16 and C/EBP-beta is sufficient to induce a fully functional brown fat program in naive fibroblastic cells, including skin fibroblasts from mouse and man. Transplantation of fibroblasts expressing these two factors into mice gives rise to an ectopic fat pad with the morphological and biochemical characteristics of brown fat. Like endogenous brown fat, this synthetic brown fat tissue acts as a sink for glucose uptake, as determined by positron emission tomography with fluorodeoxyglucose. These data indicate that the PRDM16-C/EBP-beta complex initiates brown fat formation from myoblastic precursors, and may provide opportunities for the development of new therapeutics for obesity and type-2 diabetes.