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1.
Integr Comp Biol ; 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35595475

RESUMO

Archosauria diversified throughout the Triassic Period before experiencing two mass extinctions near its end ∼201 Mya, leaving only the crocodile-lineage (Crocodylomorpha) and bird-lineage (Dinosauria) as survivors; along with the pterosaurian flying reptiles. About 50 years ago, the "locomotor superiority hypothesis" (LSH) proposed that dinosaurs ultimately dominated by the Early Jurassic Period because their locomotion was superior to other archosaurs'. This idea has been debated continuously since, with taxonomic and morphological analyses suggesting dinosaurs were "lucky" rather than surviving due to being biologically superior. However, the LSH has never been tested biomechanically. Here we present integration of experimental data from locomotion in extant archosaurs with inverse and predictive simulations of the same behaviours using musculoskeletal models, showing that we can reliably predict how extant archosaurs walk, run and jump. These simulations have been guiding predictive simulations of extinct archosaurs to estimate how they moved, and we show our progress in that endeavour. The musculoskeletal models used in these simulations can also be used for simpler analyses of form and function such as muscle moment arms, which inform us about more basic biomechanical similarities and differences between archosaurs. Placing all these data into an evolutionary and biomechanical context, we take a fresh look at the LSH as part of a critical review of competing hypotheses for why dinosaurs (and a few other archosaur clades) survived the Late Triassic extinctions. Early dinosaurs had some quantifiable differences in locomotor function and performance vs. some other archosaurs, but other derived dinosaurian features (e.g., metabolic or growth rates, ventilatory abilities) are not necessarily mutually exclusive from the LSH; or maybe even an opportunistic replacement hypothesis; in explaining dinosaurs' success.

2.
Transplant Proc ; 50(5): 1243-1248, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29880342

RESUMO

BACKGROUND: The mammalian target of rapamycin (mTOR) pathway has been shown to be central to cyst formation and growth in patients with autosomal dominant polycystic kidney disease (ADPKD). Drugs that suppress mTOR signaling are frequently used as antiproliferative agents for maintenance immunosuppression in patients who have undergone kidney transplantation. The aim of this study was to determine the effect of sirolimus, an mTOR inhibitor, on cyst volume regression in patients with ADPKD who have undergone renal transplantation. METHODS: In this single-center, prospective, open-label, parallel-group, randomized trial, 23 adult patients with ADPKD who successfully underwent renal transplantation from 2008 to 2012 were subsequently randomized (on a 1:1 basis) to a maintenance immunosuppression regimen with either sirolimus (sirolimus, tacrolimus, prednisone) or mycophenolate (mycophenolate, tacrolimus, prednisone). Total kidney volumes were measured by means of high-resolution magnetic resonance imaging within 2 weeks after transplantation and at 1 year. The primary end point was change in total kidney volume at 1 year. RESULTS: Sixteen patients completed the 1-year study (8 patients in each group). There was a decrease in kidney volume in both the sirolimus group (percentage change from baseline, 20.5%; P < .001) and mycophenolate group (percentage change from baseline, 17%; P = .048), but there was no significant difference in percentage change of total kidney volume between the groups (P = .665). CONCLUSIONS: In ADPKD patients at 1 year after kidney transplantation, there was a similar decrease in polycystic kidney volume in patients receiving an immunosuppression regimen containing sirolimus compared with patients receiving mycophenolate.


Assuntos
Imunossupressores/uso terapêutico , Rim Policístico Autossômico Dominante/tratamento farmacológico , Rim Policístico Autossômico Dominante/patologia , Rim Policístico Autossômico Dominante/cirurgia , Sirolimo/uso terapêutico , Adulto , Feminino , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Projetos de Pesquisa , Serina-Treonina Quinases TOR/antagonistas & inibidores
3.
BMC Health Serv Res ; 18(1): 200, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29566687

RESUMO

BACKGROUND: A growing number of Local Authorities (LAs) have introduced integrated wellness services as part of efforts to deliver cost effective, preventive services that address the social determinants of health. This study examined which elements of an integrated wellness service in the north east of England were effective in improving health and wellbeing (HWB). METHODS: The study used a mixed-methods approach. In-depth semi-structured interviews (IVs) were conducted with integrated wellness service users (n = 25) and focus groups (FGs) with group based service users (n = 14) and non-service users (n = 23) to gather the views of stakeholders. Findings are presented here alongside analysis of routine monitoring data. The different data were compared to examine what each data source revealed about the effectiveness of the service. RESULTS: Findings suggest that integrated wellness services work by addressing the social determinants of health and respond to multiple complex health and social concerns rather than single issues. The paper identifies examples of 'active ingredients' at the heart of the programme, such as sustained relationships, peer support and confidence building, as well as the activities through which changes take place, such as sports and leisure opportunities which in turn encourage social interaction. Wider wellbeing outcomes, including reduced social isolation and increased self-efficacy are also reported. Practical and motivational support helped build community capacity by encouraging community groups to access funding, helped navigate bureaucratic systems, and promoted understanding of marginalised communities. Fully integrated wellness services could support progression opportunities through volunteering and mentoring. CONCLUSIONS: An integrated wellness service that offers a holistic approach was valued by service users and allowed them to address complex issues simultaneously. Few of the reported health gains were captured in routine data. Quantitative and qualitative data each offered a partial view of how effectively services were working.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Promoção da Saúde/métodos , Serviços de Saúde Mental/organização & administração , Adulto , Inglaterra , Feminino , Grupos Focais , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Determinantes Sociais da Saúde
4.
J Public Health (Oxf) ; 40(suppl_1): i64-i70, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29538721

RESUMO

Background: Embedded research (ER) is recognized as one way to strengthen the integration of evidence into public health (PH) practice. In this paper, we outline a promising example of the co-production of research evidence between Fuse, the UKCRC Centre for Translational Research in Public Health and a local authority (LA) in north east England. Methods: We critically examine attempts to share and use research findings to influence decision-making in a LA setting, drawing on insights from PH practitioners, managers, commissioners and academic partners involved in this organizational case study. We highlight what can be achieved as a co-located embedded researcher. Results: The benefits and risks of ER are explored, alongside our reflections on the added value of this approach and the institutional prerequisites necessary for it to work. We argue that while this is not a new methodological approach, its application in PH as a way to facilitate evidence use is novel, and raises pragmatic and theoretical questions about the nature of impact and the extent to which it can be engineered. Conclusion: With increased situated understanding of organizational culture and norms and greater awareness of the socio-political realities of PH, ER enables new co-produced solutions to become possible.


Assuntos
Prática Clínica Baseada em Evidências/métodos , Pesquisa sobre Serviços de Saúde/métodos , Prática de Saúde Pública , Fortalecimento Institucional , Tomada de Decisões Gerenciais , Pesquisa sobre Serviços de Saúde/organização & administração , Humanos , Pesquisa Translacional Biomédica/métodos , Pesquisa Translacional Biomédica/organização & administração , Reino Unido
5.
Prev Vet Med ; 149: 92-97, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29290305

RESUMO

Following a large outbreak of Newcastle disease (ND) in Israel, a cross-sectional study was conducted in the broilers sector. The aim of the study was to find geographical and farm related risk factors for ND. Information was available on 96% of the broiler farms in Israel. Of these, farms diagnosed with ND in the years 2010-2012 were compared with the other farms. Risk factors for ND were analyzed, using Generalized Estimating Equation models. Six variables were found to be associated with the risk for ND outbreak: a distance of less than 300m from another farm (OR=1.77, 95% CI 1.07-2.93), a distance of less than 6000m from a national border (OR=2.00, 95% CI 1.22-3.30), farm location in the Ha'amakim district (OR=2.46, 95% CI 1.32-4.61), village type: a Moshav (village) vs. Kibbutz (Cooperative village) (OR=1.96, 95% CI 1.04-3.70), and carcass disposal in an uncovered bin (OR=1.96, 95% CI 1.18-3.26). A distance of less than 800m from an inter-city road was found to be a protective factor (OR=0.60, 95% CI 0.37-0.98). The results of this study provide information that may be used to improve surveillance and control of ND.


Assuntos
Galinhas , Surtos de Doenças/veterinária , Doença de Newcastle/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Animais , Estudos Transversais , Israel/epidemiologia , Doença de Newcastle/virologia , Doenças das Aves Domésticas/virologia , Fatores de Risco
6.
Public Health ; 152: 99-107, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28881219

RESUMO

OBJECTIVE: The objective of this article is to examine the factors affecting the design, commissioning and delivery of integrated health and well-being services (IHWSs), which seek to address multiple health-related behaviours, improve well-being and tackle health inequalities using holistic approaches. STUDY DESIGN: Qualitative studies embedded within iterative process evaluations. METHODS: Semi-structured interviews conducted with 16 key informants as part of two separate evaluations of IHWSs in North East England, supplemented by informal observations of service delivery. Transcripts and fieldnotes were analysed thematically. RESULTS: The study findings identify a challenging organisational context in which to implement innovative service redesign, as a result of budget cuts and changes in NHS and local authority capacity. Pressures to demonstrate outcomes affected the ability to negotiate the practicalities of joint working. Progress is at risk of being undermined by pressures to disinvest before the long-term benefits to population health and well-being are realised. The findings raise important questions about contract management and relationships between commissioners and providers involved in implementing these new ways of working. CONCLUSIONS: These findings provide useful learning in terms of the delivery and commissioning of similar IHWSs, contributing to understanding of the benefits and challenges of this model of working.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Serviços de Saúde Mental/organização & administração , Inglaterra , Feminino , Humanos , Masculino , Modelos Organizacionais , Pesquisa Qualitativa
7.
Am J Transplant ; 17(4): 901-911, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27997071

RESUMO

Thirteen percent of individuals of African ancestry express two variant copies of the gene encoding apolipoprotein 1 (APOL1) that has been associated with an increased risk of end-stage renal disease (ESRD) in the general population. Limited studies suggest that the survival of transplanted kidneys from donors expressing two APOL1 risk alleles is inferior to that of kidneys from donors with zero or one risk allele. In living kidney donation, two case reports describe donors expressing two APOL1 risk alleles who developed ESRD. Given the potential impact of APOL1 variants on the utility and safety of kidney transplantation and living kidney donation, the American Society of Transplantation convened a meeting with the goals of summarizing the current state of knowledge with respect to transplantation and APOL1, identifying knowledge gaps and studies to address these gaps, and considering approaches to integrating APOL1 into clinical practice. The authors recognize that current data are not sufficient to support traditional evidence-based guidelines but also recognize that it may require several years to generate the necessary data. Thus, approaches as to how APOL1 might currently be integrated into the clinical decision-making process were considered. This report summarizes the group's deliberations.


Assuntos
Apolipoproteína L1/genética , Tomada de Decisão Clínica , Variação Genética , Falência Renal Crônica/diagnóstico , Transplante de Rim , Padrões de Prática Médica/normas , Congressos como Assunto , Humanos , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/genética
9.
Am J Transplant ; 16(12): 3458-3467, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27140940

RESUMO

Antibodies to donor-specific HLA antigens (donor-specific antibodies [DSA]) detected by single-antigen bead (SAB) analysis prior to kidney transplant have been associated with inferior graft outcomes. However, studies of pretransplant DSA, specifically in the setting of a negative flow cytometry crossmatch (FCXM) without desensitization therapy, are limited. Six hundred and sixty kidney and kidney-pancreas recipients with a negative pretransplant FCXM from September 2007 to August 2012 without desensitization therapy were analyzed with a median follow-up of 4.2 years. All patients underwent cell-based FCXM and SAB analysis on current and historic sera prior to transplantation. One hundred and sixty-two patients (24.5%) had DSA detected prior to transplant. One-year acute rejection rates were similar in DSA-positive versus DSA-negative patients (15.4% vs. 11.4%, respectively; p = 0.18) and were higher in those with DSA mean fluorescence intensity (MFI) greater than or equal to 3000 in multivariable analysis (p = 0.046). The estimated glomerular filtration rate (eGFR) at 3 and 4 years was lower in the DSA(+) versus the DSA(-) group (p = 0.050 at 3 years) without an impact on 5-year death-censored graft survival (89.0% vs. 90.6%, respectively; p = 0.53). Timing (current or historic) of DSA detection did not alter these findings. In conclusion, pretransplant DSA in the setting of a negative FCXM confers minimal immunologic risk in the intermediate term, does not necessitate desensitization therapy and should not represent a barrier to renal transplant.


Assuntos
Citometria de Fluxo/métodos , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Teste de Histocompatibilidade/métodos , Isoanticorpos/imunologia , Transplante de Rim , Doadores de Tecidos , Dessensibilização Imunológica , Feminino , Seguimentos , Taxa de Filtração Glomerular , Antígenos HLA/imunologia , Humanos , Falência Renal Crônica/imunologia , Falência Renal Crônica/cirurgia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Transplantados
10.
Am J Transplant ; 16(9): 2532-44, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26932352

RESUMO

Both acute and chronic kidney disease are common after liver transplantation and result in significant morbidity and mortality. The introduction of the Model for End-stage Liver Disease score has directly correlated with an increased prevalence of perioperative renal dysfunction and the number of simultaneous liver-kidney transplantations performed. Kidney dysfunction in this population is typically multifactorial and related to preexisting conditions, pretransplantation renal injury, perioperative events, and posttransplantation nephrotoxic immunosuppressive therapies. The management of kidney disease after liver transplantation is challenging, as by the time the serum creatinine level is significantly elevated, few interventions affect the course of progression. Also, immunological factors such as antibody-mediated kidney rejection have become of greater interest given the rising liver-kidney transplant population. Therefore, this review, assembled by experts in the field and endorsed by the American Society of Transplantation Liver and Intestine Community of Practice, provides a critical assessment of measures of renal function and interventions aimed at preserving renal function early and late after liver and simultaneous liver-kidney transplantation. Key points and practice-based recommendations for the prevention and management of kidney injury in this population are provided to offer guidance for clinicians and identify gaps in knowledge for future investigations.


Assuntos
Intestinos/transplante , Falência Renal Crônica/prevenção & controle , Transplante de Fígado/efeitos adversos , Guias de Prática Clínica como Assunto/normas , Humanos , Falência Renal Crônica/etiologia , Sociedades Médicas
11.
Am J Transplant ; 16(6): 1923-1927, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26849829

RESUMO

Two common polymorphisms in APOL1 (G1 and G2) are conserved in persons of African ancestry, and the presence of two polymorphisms (commonly referred to as risk variants) has been identified as a risk factor for chronic kidney disease and focal seg-mental glomerulosclerosis. In kidney transplantation, deceased donors with two APOL1 risk variants carry an increased risk of renal allograft failure in the recipient. An emerging question is whether these data should influence deceased donor assessment or be used to refine prediction of allograft survival. We present the first detailed report of two cases of recipient glomerular disease in the first year following transplant from a deceased donor later defined as carrying two APOL1 risk variants. A possible "second hit" predisposing to renal disease in these recipients is discussed, one with active cytomegalovirus infection concurrent with collapsing glomerulopathy and renal failure and the other with chronic, slowly healing wound infection and focal segmental glomeru-losclerosis but stable renal function. In retrospect, awareness of the donor APOL1 risk alleles would not have influenced donor selection and ultimately did not influence posttransplant management. These case reports inform further discussion of the value of APOL1 testing for deceased donors.

12.
Bone Marrow Transplant ; 50(2): 165-72, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25347008

RESUMO

Given age-related differences in drug metabolism and indications for hematopoietic SCT (HSCT), personalized drug dosing of the conditioning regimen and post-transplant immunosuppression may reduce graft rejection, relapse rates and toxicity in pediatric HSCT recipients. This manuscript summarizes the pharmacokinetic/dynamic data of HSCT conditioning and post-grafting immunosuppression, presented at the First Annual Pediatric Bone Marrow Transplant Consortium (PBMTC) meeting in April 2013. Personalized dosing of BU to a target plasma exposure reduces graft rejection in children and improves relapse/toxicity rates in adults. Current weight-based dosing achieves the target BU exposure in only a minority (24.3%) of children. The initial BU dose should be based on the European Medicines Agency nomogram or population pharmacokinetic models to improve the numbers of children achieving the target exposure. There are limited pharmacokinetic data for treosulfan, CY, fludarabine and alemtuzumab as HSCT conditioning in children. For post-grafting immunosuppression, mycophenolic acid (MPA) clearance may be increased in younger children (<12 years). The preferred MPA pharmacokinetic monitoring parameters and target range are still evolving in HSCT recipients. Multi-institutional trials incorporating properly powered pharmacokinetic/dynamic studies are needed to assess the effect of variability in the plasma exposure of drugs/metabolites on clinical outcomes in pediatric HSCT recipients.


Assuntos
Rejeição de Enxerto/prevenção & controle , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/farmacocinética , Imunossupressores/uso terapêutico , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Congressos como Assunto , Feminino , Humanos , Lactente , Masculino
13.
Am J Transplant ; 14(5): 1164-72, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24725967

RESUMO

There are no minimally invasive diagnostic metrics for acute kidney transplant rejection (AR), especially in the setting of the common confounding diagnosis, acute dysfunction with no rejection (ADNR). Thus, though kidney transplant biopsies remain the gold standard, they are invasive, have substantial risks, sampling error issues and significant costs and are not suitable for serial monitoring. Global gene expression profiles of 148 peripheral blood samples from transplant patients with excellent function and normal histology (TX; n = 46), AR (n = 63) and ADNR (n = 39), from two independent cohorts were analyzed with DNA microarrays. We applied a new normalization tool, frozen robust multi-array analysis, particularly suitable for clinical diagnostics, multiple prediction tools to discover, refine and validate robust molecular classifiers and we tested a novel one-by-one analysis strategy to model the real clinical application of this test. Multiple three-way classifier tools identified 200 highest value probesets with sensitivity, specificity, positive predictive value, negative predictive value and area under the curve for the validation cohort ranging from 82% to 100%, 76% to 95%, 76% to 95%, 79% to 100%, 84% to 100% and 0.817 to 0.968, respectively. We conclude that peripheral blood gene expression profiling can be used as a minimally invasive tool to accurately reveal TX, AR and ADNR in the setting of acute kidney transplant dysfunction.


Assuntos
Biomarcadores/sangue , Perfilação da Expressão Gênica , Rejeição de Enxerto/sangue , Rejeição de Enxerto/classificação , Falência Renal Crônica/cirurgia , Transplante de Rim , Complicações Pós-Operatórias/genética , Adulto , Área Sob a Curva , Reações Falso-Negativas , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Humanos , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Complicações Pós-Operatórias/sangue , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade
14.
Am J Transplant ; 14(6): 1346-55, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24751150

RESUMO

TOL101 is a murine IgM mAb targeting the αß TCR. Unlike other T cell targets, the αß TCR has no known intracellular signaling domains and may provide a nonmitogenic target for T cell inactivation. We report the 6-month Phase 2 trial data testing TOL101 in kidney transplantation. The study was designed to identify a dose that resulted in significant CD3 T cell modulation (<25 T cell/mm(3) ), to examine the safety and tolerability of TOL101 and to obtain preliminary efficacy information. Thirty-six patients were enrolled and given 5-10 daily doses of TOL101; 33 patients completed dosing, while three discontinued after two doses due to a self-limiting urticarial rash. Infusion adjustments, antihistamines, steroids and dose escalation of TOL101 reduced the incidence of the rash. Doses of TOL101 above 28 mg resulted in prolonged CD3 modulation, with rapid recovery observed 7 days after therapy cessation. There were no cases of patient or graft loss. Few significant adverse events were reported, with one nosocomial pneumonia. There were five biopsy-confirmed acute cellular rejections (13.9%); however, no donor-specific antibodies were detected. Overall TOL101 was well-tolerated, supporting continued clinical development using the dose escalating 21-28-42-42-42 mg regimen.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Transplante de Rim , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade
15.
Clin Transplant ; 27(6): E625-35, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24033455

RESUMO

Data were pooled from three prospective, multicenter trials in which 1996 de novo kidney transplant recipients were randomized to everolimus 1.5 or 3.0 mg or mycophenolic acid (MPA), with cyclosporine and steroids. Wound healing complications reported as adverse events were retrospectively reviewed in a blinded manner. The incidence of wound healing adverse events was 17.6% (351 of 1996) by day 90 and was similar for everolimus 1.5 mg (16.6% [110 of 661]) vs. MPA (14.3% [95 of 665]) (p = 0.255), but higher with everolimus 3.0 mg (21.8% [146 of 670]) (p < 0.001 vs. MPA). Similar results were observed for wound healing complications reported as serious adverse events. The 12-month incidence of lymphocele was 11.2% with everolimus 1.5 mg and 8.9% with MPA (p = 0.171), but lymphocele reported as a serious adverse event were more frequent with everolimus 1.5 mg (6.5% vs. 3.5%; p = 0.012). The hazard ratio (HR) for any wound healing complication vs. MPA was not significantly higher for everolimus <3 ng/mL (HR 1.33; 95% CI 0.94-1.88; p = 0.104), but increased to 1.46 (95% CI 1.12-1.90; p = 0.005) for 3-8 ng/mL and 1.69 (95% CI 1.20-2.38; p = 0.002) for >8 ng/mL. These results suggest that de novo kidney transplant patients receiving an initial everolimus dose of 1.5 mg do not appear to have a pronounced increased risk of wound healing complications vs. patients receiving MPA.


Assuntos
Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Transplante de Rim , Sirolimo/análogos & derivados , Cicatrização/efeitos dos fármacos , Adulto , Ciclosporina/uso terapêutico , Everolimo , Feminino , Seguimentos , Taxa de Filtração Glomerular , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Prognóstico , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Fatores de Risco , Sirolimo/uso terapêutico
16.
Bone Marrow Transplant ; 48(11): 1415-20, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23933764

RESUMO

Reduced-intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (allo-HCT) can cure patients with AML in CR. However, relapse after RIC allo-HCT may indicate heterogeneity in the stringency of CR. Strict definition of CR requires no evidence of leukemia by both morphologic and flow cytometric criteria. We re-evaluated 85 AML patients receiving RIC allo-HCT in CR to test if a strict definition of CR had direct implications for the outcome. These patients had leukemia immunophenotype documented at diagnosis and analyzed at allo-HCT. Eight (9.4%) had persistent leukemia by flow cytometric criteria at allo-HCT. The patients with immunophenotypic persistent leukemia had a significantly increased relapse (hazard ratio (HR): 3.7; 95% confidence interval (CI): 1.3-10.3, P=0.01) and decreased survival (HR: 2.9; 95% CI: 1.3-6.4, P<0.01) versus 77 patients in CR by both morphology and flow cytometry. However, the pre-allo-HCT bone marrow (BM) blast count (that is, 0-4%) was not significantly associated with risks of relapse or survival. These data indicate the presence of leukemic cells, but not the BM blast count affects survival. A strict morphologic and clinical lab flow cytometric definition of CR predicts outcomes after RIC allo-HCT, and therefore is critical to achieve at transplantation.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia Mieloide Aguda/terapia , Neoplasia Residual/terapia , Condicionamento Pré-Transplante/métodos , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Imunofenotipagem , Leucemia Mieloide Aguda/cirurgia , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/cirurgia , Prognóstico , Estudos Retrospectivos , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
17.
Am J Transplant ; 13(2): 442-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23205690

RESUMO

Although mTOR inhibitor use has been associated with proteinuria in kidney transplant recipients, dose dependency and impact on allograft function are unknown. In a post hoc analysis, we compared rates of proteinuria 3 months posttransplant among everolimus (EVR) and mycophenolate (MPA) treatment arms and used a time-dependent model to correlate the risk of proteinuria to EVR trough levels up to 24 months posttransplant. eGFR and graft loss was compared by proteinuria status at 3 months. Of 833 randomized patients, 24%, 36% and 19% of lower exposure EVR (1.5 mg/day), higher exposure EVR (3.0 mg/day) and MPA-treated patients had proteinuria ≥ 300 mg/g Cr at 3 months, respectively. EVR 1.5 was not associated with an increase in risk of proteinuria (HR 1.20; p = 0.19) unlike EVR 3.0 (HR 1.84; p < 0.001) versus MPA. EVR trough levels >8 ng/mL were significantly associated with proteinuria compared to 3-8 ng/mL (HR 1.86; p < 0.001). Those patients with proteinuria at 3 months and those who developed proteinuria thereafter had lower eGFR and higher graft loss at 24 months, regardless of treatment arm. We identify a dose-dependent effect of EVR with the risk of proteinuria; however, its independent impact upon eGFR and graft survival at 2 years was not evident.


Assuntos
Imunossupressores/uso terapêutico , Transplante de Rim/métodos , Ácido Micofenólico/uso terapêutico , Proteinúria/tratamento farmacológico , Sirolimo/análogos & derivados , Adulto , Ciclosporina/uso terapêutico , Relação Dose-Resposta a Droga , Everolimo , Feminino , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Proteinúria/sangue , Fatores de Risco , Sirolimo/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
18.
Transplant Proc ; 42(6): 2055-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20692406

RESUMO

BACKGROUND: Exocrine tissue is commonly cotransplanted with islets in autografting and allotransplantation of impure preparations. Proteases and insulin are released by acinar cells and islets, respectively, during pretransplantation culture and also systemically after transplantation. We hypothesized that released proteases could cleave insulin molecules and that addition of alpha-1 antitrypsin (A1AT) to impure islet cultures would block this cleavage, improving islet recovery and function. METHODS: Trypsin, chymotrypsin, and elastase (TCE) activity and insulin levels were measured in culture supernates of pure (n = 5) and impure (n = 5) islet fractions, which were isolated from deceased donors. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to detect insulin after incubation with proteases. We assessed the effects of A1AT supplementation (0.5 mg/mL; n = 4] on TCE activity, insulin levels, culture recovery, and islet quality. The ultrastructure of islets exposed to TCE versus control medium was examined using electron microscopy (EM). RESULTS: Protease (TCE) activity in culture supernatants was indirectly proportional to the percentage purity of islets: pure, impure, or highly impure. Increasingly lower levels of insulin were detected in culture supernatants when higher protease activity levels were present. Insulin levels measured from supernatants of impure and highly impure islet preparations were 61 +/- 23.7% and 34 +/- 33% of that in pure preparations, respectively. Incubation with commercially available proteases (TCE) or exocrine acinar cell supernatant cleaved insulin molecules as assessed using SDS-PAGE. Addition of A1AT to impure islet preparations reduced protease activity and restored normal insulin levels as detected using enzyme-linked immunosorbent assay (ELISA) and SDS-PAGE of culture supernates. A1AT improved insulin levels to 98% +/- 1.3% in impure and 78% +/- 34.2% in highly impure fractions compared with pure islet fractions. A1AT supplementation improved postculture recovery of islets in impure preparations compared with nontreated controls (72% +/- 9% vs 47% +/- 15%). Islet viability as measured using membrane integrity assays was similar in both the control (98% +/- 2%) and the A1AT-treated groups (99% +/- 1%). EM results revealed a reduction or absence of secretory granules after exposure to proteases (TCE). CONCLUSION: Culture of impure human islet fractions in the presence of A1AT prevented insulin cleavage and improved islet recovery. A1AT supplementation of islet culture media, therefore, may increase the proportion of human islet products that meet release criteria for transplantation.


Assuntos
Insulina/metabolismo , Transplante das Ilhotas Pancreáticas/fisiologia , Ilhotas Pancreáticas/citologia , alfa 1-Antitripsina/metabolismo , Cadáver , Técnicas de Cultura de Células/métodos , Quimotripsina/metabolismo , Sobrevivência de Enxerto , Humanos , Insulina/isolamento & purificação , Ilhotas Pancreáticas/enzimologia , Ilhotas Pancreáticas/metabolismo , Elastase Pancreática/metabolismo , Doadores de Tecidos , Transplante Autólogo , Transplante Homólogo , Tripsina/metabolismo , alfa 1-Antitripsina/uso terapêutico
19.
Clin Nephrol ; 73(5): 333-43, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20420793

RESUMO

The last several decades have seen a substantial decrease in the prevalence of acute allograft rejection in kidney transplant recipients, while equivalent improvements in long-term graft function have not been realized. As a result, the primary focus of new immunosuppressive drug development has expanded to include ease of use, improved side effect profiles, and reduced nephrotoxicity in addition to the more traditional goal of improved short-term outcomes. A number of novel drugs are currently under investigation in Phase I, II, or III clinical trials primarily to replace the nephrotoxic but highly effective calcineurin inhibitors. ISA247 (voclosporine) is a cyclosporine (CsA) analog with reduced nephrotoxicity in Phase III study. AEB071 (sotrastaurin), a protein kinase C inhibitor, and CP-690550, a JAK3 inhibitor, are small molecules in Phase II studies. Everolimus is derived from the mTOR inhibitor sirolimus and is in Phase III study. Belatacept is a humanized antibody that inhibits T-cell costimulation and has shown encouraging results in multiple Phase II and III trials. Alefacept and Efaluzimab are humanized antibodies that inhibit T-cell adhesion and are in Phase I and II clinical trials. This article reviews the mechanisms of action as well as published and preliminary results of the Phase I-III clinical trials involving these novel immunosuppressive agents.


Assuntos
Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/farmacologia , Transplante de Rim , Abatacepte , Alefacept , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Ciclosporina/farmacologia , Everolimo , Humanos , Imunoconjugados/farmacologia , Piperidinas , Pirimidinas/farmacologia , Pirróis/farmacologia , Quinazolinas/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Sirolimo/análogos & derivados , Sirolimo/farmacologia
20.
Diabetologia ; 50(8): 1649-59, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17593347

RESUMO

AIMS/HYPOTHESIS: Transplantation of islets is a viable option for the treatment of diabetes. A significant proportion of islets is lost during isolation, storage and after transplantation as a result of apoptosis. cAMP response element binding protein (CREB) is an important cell survival factor. The aim of the present study was to determine whether preservation of CREB function is needed for survival of human islets. MATERIALS AND METHODS: To determine the effects of downregulation of CREB activity on beta cell apoptosis in a transplantation setting, adenoviral vectors were used to express two dominant negative mutant forms of CREB in human islets isolated from cadaveric donors. Markers of apoptosis were determined in these transduced islets under basal conditions and following treatment with growth factor. RESULTS: Expression of CREB mutants in human islets resulted in significant (p < 0.001) activation of caspase-9, a key regulatory enzyme in the mitochondrial pathway of apoptosis, when compared with islets transduced with adenoviral beta galactosidase. Immunocytochemical analysis showed the activation of caspase-9 to be predominantly in beta cells. Other definitive markers of apoptosis such as parallel activation of caspase-3, accumulation of cleaved poly-(ADP-ribose) polymerase and nuclear condensation were also observed. Furthermore, the anti-apoptotic action of growth factors exendin-4 and betacellulin in human islets exposed to cytokines was partially lost when CREB function was impaired. CONCLUSIONS/INTERPRETATION: Our findings suggest that impairment of CREB-mediated transcription could lead to loss of islets by apoptosis with potential implications in islet transplantation as well as in the mechanism of beta cell loss leading to diabetes.


Assuntos
Apoptose/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Mutação , Adenoviridae/genética , Apoptose/genética , Apoptose/fisiologia , Betacelulina , Cadáver , Caspase 9/metabolismo , Caspases/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Citocinas/farmacologia , Exenatida , Genes Dominantes , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Immunoblotting , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Ilhotas Pancreáticas/metabolismo , Peptídeos/farmacologia , Transfecção , Peçonhas/farmacologia
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