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1.
Blood ; 141(10): 1136-1146, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36395067

RESUMO

Acute graft-versus-host disease (GVHD) is a rare complication after solid organ transplantation (SOT) that carries high mortality. Caused by immunocompetent donor leukocytes within the transplanted organ, which become activated against recipient tissues, GVHD typically develops 2 to 12 weeks after SOT and can affect the skin, gastrointestinal tract, liver, and bone marrow. Signs and symptoms are nonspecific and include a rash, nausea, appetite loss, diarrhea, and cytopenias. Pancytopenia from marrow-directed GVHD is the primary driver of mortality. The diagnosis of GVHD is often delayed but should be confirmed by biopsy of an affected organ. Evidence of donor chimerism in blood or marrow supports the diagnosis. When GVHD is diagnosed we initiate treatment with systemic corticosteroids. At that time, if GVHD only involves skin or oral mucosa we also decrease maintenance immunosuppression levels to allow the recipient to reject the donor immune cells. For GVHD involving the marrow we initiate an allogeneic hematopoietic cell donor search early. In this article, we describe 3 cases of GVHD after SOT, outline our approach to diagnosis and management, and then provide analysis of the 3 instructive cases.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Órgãos , Pancitopenia , Humanos , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/terapia , Transplante de Órgãos/efeitos adversos , Medula Óssea , Pancitopenia/complicações , Corticosteroides , Transplante de Medula Óssea/efeitos adversos
2.
Health Expect ; 27(3): e14081, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38845155

RESUMO

BACKGROUND: Patient and public involvement and engagement (PPIE) have long been considered important to good research practice. There is growing, yet diverse, evidence in support of PPIE with children and young people (CYP). We must now understand the various approaches to involvement of CYP in research. AIMS: This rapid umbrella review aimed to provide an overview of when, how and to what extent CYP are involved in the conduct of health research, as well as the reported benefits, challenges, and facilitators of involvement. METHODS: We searched OVID Medline, Embase and PubMed. Published reviews were included if they reported meaningful involvement of CYP in the conduct of health research. Extracted data were synthesised using thematic analysis. RESULTS: The 26 reviews included were predominately systematic and scoping reviews, published within the last decade, and originating from North America and the United Kingdom. CYPs were involved in all stages of research across the literature, most commonly during research design and data collection, and rarely during research funding or data sharing and access. Researchers mostly engaged CYP using focus groups, interviews, advisory panels, questionnaires, and to a lesser extent arts-based approaches such as photovoice and drawing. Visual and active creative methods were more commonly used with children ≤12 years. The evidence showed a shared understanding of the benefits, challenges, and facilitators for involvement of CYP, such as time and resource commitment and building partnership. CONCLUSION: Overall, the review identified consistency in the range of methods and approaches used, and stages of research with which CYP are commonly involved. There is a need for more consistent reporting of PPIE in the literature, both in terminology and detail used. Furthermore, the impact of approaches to CYP involvement on research and community outcomes must be better evaluated. PATIENT/PUBLIC CONTRIBUTION: This review forms part of broader research initiatives being led by the authors. Together, these projects aim to support embedding of child voices in research practice and to explore the desirability and suitability of Young Persons Advisory Groups within birth cohort studies. The findings from this review, alongside public and stakeholder consultation, will inform development of resources such as practice recommendations to guide future involvement of CYP in health research undertaken at the author's respective institutions.


Assuntos
Participação do Paciente , Humanos , Criança , Adolescente , Projetos de Pesquisa , Pesquisa sobre Serviços de Saúde , Participação da Comunidade
3.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34475208

RESUMO

In human neurodegenerative diseases, neurons can transfer toxic protein aggregates to surrounding cells, promoting pathology via poorly understood mechanisms. In Caenorhabditis elegans, proteostressed neurons can expel neurotoxic proteins in large, membrane-bound vesicles called exophers. We investigated how specific stresses impact neuronal trash expulsion to show that neuronal exopher production can be markedly elevated by oxidative and osmotic stress. Unexpectedly, we also found that fasting dramatically increases exophergenesis. Mechanistic dissection focused on identifying nonautonomous factors that sense and activate the fasting-induced exopher response revealed that DAF16/FOXO-dependent and -independent processes are engaged. Fasting-induced exopher elevation requires the intestinal peptide transporter PEPT-1, lipid synthesis transcription factors Mediator complex MDT-15 and SBP-1/SREPB1, and fatty acid synthase FASN-1, implicating remotely initiated lipid signaling in neuronal trash elimination. A conserved fibroblast growth factor (FGF)/RAS/MAPK signaling pathway that acts downstream of, or in parallel to, lipid signaling also promotes fasting-induced neuronal exopher elevation. A germline-based epidermal growth factor (EGF) signal that acts through neurons is also required for exopher production. Our data define a nonautonomous network that links food availability changes to remote, and extreme, neuronal homeostasis responses relevant to aggregate transfer biology.


Assuntos
Lipogênese/fisiologia , Estresse Fisiológico/fisiologia , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Genes ras/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Oxirredução , Transdução de Sinais
4.
Eur J Haematol ; 111(6): 863-871, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37670560

RESUMO

OBJECTIVES: We recently performed a single-arm phase II trial of DA-EPOCH in adults with acute lymphoblastic leukemia (ALL). We sought to compare these results to those with standard Hyper-CVAD. METHODS: We created a retrospective matched cohort of patients who received Hyper-CVAD (n = 69) at our center and otherwise met eligibility criteria for the DA-EPOCH trial (n = 53). RESULTS: Our outcomes support the use of Hyper-CVAD over DA-EPOCH in Ph- disease for both overall survival (OS; HR 0.18, p = .004) and event-free survival (EFS; HR 0.51, p = .06). In contrast, outcomes were similar in Ph+ disease (OS HR 0.97, p = .96; EFS HR 0.65, p = .21). Rates of morphologic remission and measurable residual-disease negativity were similar between the regimens. Hyper-CVAD was associated with significantly more febrile neutropenia (OR 1.9, p = .03) and a greater incidence of Grade 4 or 5 adverse events (20% vs. 6%). Average transfusions per cycle of both red blood cells (p < .001) and platelets (p < .001) were five-fold higher with Hyper-CVAD. CONCLUSIONS: Our findings support continued use of Hyper-CVAD for Ph- ALL but suggest that DA-EPOCH may be a reasonable alternative for Ph+ ALL. These data also highlight a potential role for DA-EPOCH in resource-limited settings or when more intense therapy is not feasible.


Assuntos
Doxorrubicina , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Humanos , Estudos Retrospectivos , Doxorrubicina/uso terapêutico , Ciclofosfamida/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Vincristina/uso terapêutico , Dexametasona
5.
Angew Chem Int Ed Engl ; 62(45): e202310307, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37705304

RESUMO

Reactions of a dicopper(I) tert-butoxide complex with alkynes possessing boryl or silyl capping groups resulted in formation of unprecedented tetracopper(I) µ-acetylide/diyne complexes that were characterized by NMR and UV/Vis spectroscopy, mass spectrometry and single-crystal X-ray diffraction. These compounds possess an unusual µ4 -η1 :η1 :η1 :η1 coordination mode for the bridging organic fragment, enforced by the rigid and dinucleating nature of the ligand utilized. Thus, the central π system remains unperturbed and accessible for subsequent reactivity and modification. This has been corroborated by addition of a fifth copper atom, giving rise to a pentacopper acetylide complex. This work may provide a new approach by which metal-metal cooperativity can be exploited in the transformation of acetylide and diyne groups to a variety of substrates, or as a starting point for the controlled synthesis of copper(I) alkyne-containing clusters.

6.
Liver Transpl ; 28(3): 407-421, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34587357

RESUMO

Acute graft-versus-host disease (GVHD) is a rare complication after orthotopic liver transplantation (OLT) that carries high mortality. We hypothesized that machine-learning algorithms to predict rare events would identify patients at high risk for developing GVHD. To develop a predictive model, we retrospectively evaluated the clinical features of 1938 donor-recipient pairs at the time they underwent OLT at our center; 19 (1.0%) of these recipients developed GVHD. This population was divided into training (70%) and test (30%) sets. A total of 7 machine-learning classification algorithms were built based on the training data set to identify patients at high risk for GVHD. The C5.0, heterogeneous ensemble, and generalized gradient boosting machine (GGBM) algorithms predicted that 21% to 28% of the recipients in the test data set were at high risk for developing GVHD, with an area under the receiver operating characteristic curve (AUROC) of 0.83 to 0.86. The 7 algorithms were then evaluated in a validation data set of 75 more recent donor-recipient pairs who underwent OLT at our center; 2 of these recipients developed GVHD. The logistic regression, heterogeneous ensemble, and GGBM algorithms predicted that 9% to 11% of the validation recipients were at high risk for developing GVHD, with an AUROC of 0.93 to 0.96 that included the 2 recipients who developed GVHD. In conclusion, we present a practical model that can identify patients at high risk for GVHD who may warrant additional monitoring with peripheral blood chimerism testing.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Fígado , Área Sob a Curva , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/etiologia , Humanos , Transplante de Fígado/efeitos adversos , Aprendizado de Máquina , Estudos Retrospectivos
7.
Nat Mater ; 20(8): 1130-1135, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33820963

RESUMO

Development of an efficient yet durable photoelectrode is of paramount importance for deployment of solar-fuel production. Here, we report the photoelectrochemically self-improving behaviour of a silicon/gallium nitride photocathode active for hydrogen production with a Faradaic efficiency approaching ~100%. By using a correlative approach based on different spectroscopic and microscopic techniques, as well as density functional theory calculations, we provide a mechanistic understanding of the chemical transformation that is the origin of the self-improving behaviour. A thin layer of gallium oxynitride forms on the side walls of the gallium nitride grains, via a partial oxygen substitution at nitrogen sites, and displays a higher density of catalytic sites for the hydrogen-evolving reaction. This work demonstrates that the chemical transformation of gallium nitride into gallium oxynitride leads to sustained operation and enhanced catalytic activity, thus showing promise for oxynitride layers as protective catalytic coatings for hydrogen evolution.

8.
Haematologica ; 106(6): 1599-1607, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32499241

RESUMO

We have used a non-myeloablative conditioning regimen for allogeneic hematopoietic cell transplantation for the past twenty years. During that period, changes in clinical practice have been aimed at reducing morbidity and mortality from infections, organ toxicity, and graft-versus-host disease. We hypothesized that improvements in clinical practice led to better transplantation outcomes over time. From 1997-2017, 1,720 patients with hematologic malignancies received low-dose total body irradiation +/- fludarabine or clofarabine before transplantation from HLA-matched sibling or unrelated donors, followed by mycophenolate mofetil and a calcineurin inhibitor ± sirolimus. We compared outcomes in three cohorts by year of transplantation: 1997 +/- 2003 (n=562), 2004 +/- 2009 (n=594), and 2010 +/- 2017 (n=564). The proportion of patients ≥60 years old increased from 27% in 1997 +/- 2003 to 56% in 2010-2017, and with scores from the Hematopoietic Cell Transplantation Comborbidity Index of ≥3 increased from 25% in 1997 +/- 2003 to 45% in 2010 +/- 2017. Use of unrelated donors increased from 34% in 1997 +/- 2003 to 65% in 2010-2017. When outcomes from 2004 +/- 2009 and 2010-2017 were compared to 1997 +/- 2003, improvements were noted in overall survival (P=.0001 for 2004-2009 and P <.0001 for 2010-2017), profression-free survival (P=.002 for 2004-2009 and P <.0001 for 2010 +/- 2017), non-relapse mortality (P<.0001 for 2004 +/- 2009 and P <.0001 for 2010 +/- 2017), and in rates of grades 2 +/- 4 acute and chronic graft-vs.-host disease. For patients with hematologic malignancies who underwent transplantation with non-myeloablative conditioning, outcomes have improved during the past two decades. Trials reported are registered under ClinicalTrials.gov identifiers: NCT00003145, NCT00003196, NCT00003954, NCT00005799, NCT00005801, NCT00005803, NCT00006251, NCT00014235, NCT00027820, NCT00031655, NCT00036738, NCT00045435, NCT00052546, NCT00060424, NCT00075478, NCT00078858, NCT00089011, NCT00104858, NCT00105001, NCT00110058, NCT00397813, NCT00793572, NCT01231412, NCT01252667, NCT01527045.


Assuntos
Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/etiologia , Neoplasias Hematológicas/terapia , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Condicionamento Pré-Transplante , Doadores não Relacionados
9.
FASEB J ; 34(6): 8475-8492, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32385951

RESUMO

Mitochondria are dynamic organelles that can change shape and size depending on the needs of the cell through the processes of mitochondrial fission and fusion. In this work, we investigated the role of mitochondrial dynamics in organismal stress response. By using C. elegans as a genetic model, we could visualize mitochondrial morphology in a live organism with well-established stress assays and well-characterized stress response pathways. We found that disrupting mitochondrial fission (DRP1/drp-1) or fusion (OPA1/eat-3, MFN/fzo-1) genes caused alterations in mitochondrial morphology that impacted both mitochondrial function and physiologic rates. While both mitochondrial fission and mitochondrial fusion mutants showed increased sensitivity to osmotic stress and anoxia, surprisingly we found that the mitochondrial fusion mutants eat-3 and fzo-1 are more resistant to both heat stress and oxidative stress. In exploring the mechanism of increased stress resistance, we found that disruption of mitochondrial fusion genes resulted in the upregulation of multiple stress response pathways. Overall, this work demonstrates that disrupting mitochondrial dynamics can have opposite effects on resistance to different types of stress. Our results suggest that disruption of mitochondrial fusion activates multiple stress response pathways that enhance resistance to specific stresses.


Assuntos
Caenorhabditis elegans/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/fisiologia , Estresse Oxidativo/fisiologia , Estresse Fisiológico/fisiologia , Animais , Proteínas de Caenorhabditis elegans/metabolismo , Dinaminas/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Proteínas Mitocondriais/metabolismo , Organelas/metabolismo
10.
Mol Psychiatry ; 25(10): 2355-2372, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-30038233

RESUMO

Neuropsychiatric disorders overlap in symptoms and share genetic risk factors, challenging their current classification into distinct diagnostic categories. Novel cross-disorder approaches are needed to improve our understanding of the heterogeneous nature of neuropsychiatric diseases and overcome existing bottlenecks in their diagnosis and treatment. Here we employ high-content multi-parameter phospho-specific flow cytometry, fluorescent cell barcoding and automated sample preparation to characterize ex vivo signaling network responses (n = 1764) measured at the single-cell level in B and T lymphocytes across patients diagnosed with four major neuropsychiatric disorders: autism spectrum condition (ASC), bipolar disorder (BD), major depressive disorder (MDD), and schizophrenia (SCZ; n = 25 each), alongside matched healthy controls (n = 100). We identified 25 nodes (individual cell subtype-epitope-ligand combinations) significantly altered relative to the control group, with variable overlap between different neuropsychiatric diseases and heterogeneously expressed at the level of each individual patient. Reconstruction of the diagnostic categories from the altered nodes revealed an overlapping neuropsychiatric spectrum extending from MDD on one end, through BD and SCZ, to ASC on the other end. Network analysis showed that although the pathway structure of the epitopes was broadly preserved across the clinical groups, there were multiple discrete alterations in network connectivity, such as disconnections within the antigen/integrin receptor pathway and increased negative regulation within the Akt1 pathway in CD4+ T cells from ASC and SCZ patients, in addition to increased correlation of Stat1 (pY701) and Stat5 (pY694) responses in B cells from BD and MDD patients. Our results support the "dimensional" approach to neuropsychiatric disease classification and suggest potential novel drug targets along the neuropsychiatric spectrum.


Assuntos
Transtorno do Espectro Autista , Transtorno Bipolar , Transtorno Depressivo Maior , Esquizofrenia , Transdução de Sinais , Análise de Célula Única , Transtorno do Espectro Autista/metabolismo , Transtorno Bipolar/metabolismo , Transtorno Depressivo Maior/metabolismo , Feminino , Humanos , Masculino , Esquizofrenia/metabolismo
11.
Anesth Analg ; 132(6): 1531-1544, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33861047

RESUMO

Because up to 12% of obstetric patients meet criteria for the diagnosis of thrombocytopenia in pregnancy, it is not infrequent that the anesthesiologist must decide whether to proceed with a neuraxial procedure in an affected patient. Given the potential morbidity associated with general anesthesia for cesarean delivery, thoughtful consideration of which patients with thrombocytopenia are likely to have an increased risk of spinal epidural hematoma with neuraxial procedures, and when these risks outweigh the relative benefits is important to consider and to inform shared decision making with patients. Because there are substantial risks associated with withholding a neuraxial analgesic/anesthetic procedure in obstetric patients, every effort should be made to perform a bleeding history assessment and determine the thrombocytopenia etiology before admission for delivery. Whereas multiple other professional societies (obstetric, interventional pain, and hematologic) have published guidelines addressing platelet thresholds for safe neuraxial procedures, the US anesthesia professional societies have been silent on this topic. Despite a paucity of high-quality data, there are now meta-analyses that provide better estimations of risks. An interdisciplinary taskforce was convened to unite the relevant professional societies, synthesize the data, and provide a practical decision algorithm to help inform risk-benefit discussions and shared decision making with patients. Through a systematic review and modified Delphi process, the taskforce concluded that the best available evidence indicates the risk of spinal epidural hematoma associated with a platelet count ≥70,000 × 106/L is likely to be very low in obstetric patients with thrombocytopenia secondary to gestational thrombocytopenia, immune thrombocytopenia (ITP), and hypertensive disorders of pregnancy in the absence of other risk factors. Ultimately, the decision of whether to proceed with a neuraxial procedure in an obstetric patient with thrombocytopenia occurs within a clinical context. Potentially relevant factors include, but are not limited to, patient comorbidities, obstetric risk factors, airway examination, available airway equipment, risk of general anesthesia, and patient preference.


Assuntos
Anestesia Obstétrica/normas , Consenso , Perinatologia/normas , Sociedades Médicas/normas , Trombocitopenia/terapia , Comitês Consultivos/normas , Anestesia Obstétrica/métodos , Feminino , Humanos , Perinatologia/métodos , Gravidez , Trombocitopenia/diagnóstico
12.
Small ; 16(35): e2001600, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32755006

RESUMO

The activity of polycrystalline thin film photoelectrodes is impacted by local variations of the material properties due to the exposure of different crystal facets and the presence of grain/domain boundaries. Here a multi-modal approach is applied to correlate nanoscale heterogeneities in chemical composition and electronic structure with nanoscale morphology in polycrystalline Mo-BiVO4 . By using scanning transmission X-ray microscopy, the characteristic structure of polycrystalline film is used to disentangle the different X-ray absorption spectra corresponding to grain centers and grain boundaries. Comparing both spectra reveals phase segregation of V2 O5 at grain boundaries of Mo-BiVO4 thin films, which is further supported by X-ray photoelectron spectroscopy and many-body density functional theory calculations. Theoretical calculations also enable to predict the X-ray absorption spectral fingerprint of polarons in Mo-BiVO4 . After photo-electrochemical operation, the degraded Mo-BiVO4 films show similar grain center and grain boundary spectra indicating V2 O5 dissolution in the course of the reaction. Overall, these findings provide valuable insights into the degradation mechanism and the impact of material heterogeneities on the material performance and stability of polycrystalline photoelectrodes.

13.
Brain Behav Immun ; 90: 184-195, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32861718

RESUMO

With less than half of patients with major depressive disorder (MDD) correctly diagnosed within the primary care setting, there is a clinical need to develop an objective and readily accessible test to enable earlier and more accurate diagnosis. The aim of this study was to develop diagnostic prediction models to identify MDD patients among individuals presenting with subclinical low mood, based on data from dried blood spot (DBS) proteomics (194 peptides representing 115 proteins) and a novel digital mental health assessment (102 sociodemographic, clinical and personality characteristics). To this end, we investigated 130 low mood controls, 53 currently depressed individuals with an existing MDD diagnosis (established current MDD), 40 currently depressed individuals with a new MDD diagnosis (new current MDD), and 72 currently not depressed individuals with an existing MDD diagnosis (established non-current MDD). A repeated nested cross-validation approach was used to evaluate variation in model selection and ensure model reproducibility. Prediction models that were trained to differentiate between established current MDD patients and low mood controls (AUC = 0.94 ± 0.01) demonstrated a good predictive performance when extrapolated to differentiate between new current MDD patients and low mood controls (AUC = 0.80 ± 0.01), as well as between established non-current MDD patients and low mood controls (AUC = 0.79 ± 0.01). Importantly, we identified DBS proteins A1AG1, A2GL, AL1A1, APOE and CFAH as important predictors of MDD, indicative of immune system dysregulation; as well as poor self-rated mental health, BMI, reduced daily experiences of positive emotions, and tender-mindedness. Despite the need for further validation, our preliminary findings demonstrate the potential of such prediction models to be used as a diagnostic aid for detecting MDD in clinical practice.


Assuntos
Transtorno Depressivo Maior , Transtorno Depressivo Maior/diagnóstico , Humanos , Saúde Mental , Proteômica , Reprodutibilidade dos Testes
14.
Biol Blood Marrow Transplant ; 25(7): 1331-1339, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30711779

RESUMO

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired clonal hematopoietic cell disease characterized by the destruction of hematopoietic cells through activation of the complement system with manifestations that can be life-threatening including hemolysis, thrombosis, and marrow failure. Allogeneic hematopoietic cell transplantation (HCT) remains the sole cure for PNH, but eculizumab, a terminal complement inhibitor of C5, has been used to prevent complement-mediated hemolysis in patients with PNH since its approval by the Food and Drug Administration in 2007. We examined outcomes of HCT in patients with PNH to evaluate the effects of disease subtype, conditioning intensity, and eculizumab use either pre-HCT or post-HCT. Fifty-five patients with a diagnosis of PNH underwent at least 1 HCT, with 4 patients requiring a second HCT for graft failure. The median age at the time of first HCT was 30.0 years (range, 4.2 to 66.9 years). Seventeen patients (30.9%) had classical PNH, and the remaining 38 patients had PNH associated with another marrow disorder (aplastic anemia in 26 of the 38). Indications for HCT included pancytopenia in 47.3% of the patients, myeloid malignancy (myelodysplastic syndrome, myeloproliferative neoplasm, or acute myelogenous leukemia) in 21.8%, recurrent hemolysis in 20.0%, and thrombosis in 10.9%. Of the 55 first HCTs, 26 were performed with myeloablative conditioning, 27 were performed with reduced-intensity conditioning, and 2 sets of identical twins underwent HCT without any conditioning. Donor types included HLA-matched related in 38.2%, HLA-matched unrelated in 34.5%, single HLA-allele mismatched unrelated in 16.4%, umbilical cord blood in 5.5%, syngeneic in 3.6%, and HLA-haploidentical in 1.8%. The median duration of follow-up in surviving patients was 6.1 years (range, 2.1 to 46.1 years) after first HCT. The median time to neutrophil and platelet engraftment was 17 days and 19 days, respectively; all but 2 patients (96.3%) had sustained engraftment. Overall survival was 70% at 5 years. Neither the choice of conditioning intensity nor PNH subtype affected survival. Nineteen patients died during follow-up, including 12 patients before day +365. Six patients received treatment with eculizumab before HCT, and 2 were treated after HCT. All patients treated with eculizumab were alive at a median follow-up of 2.3 years (range, .2 to 6.9 years). Both patients treated with eculizumab after HCT had minimal to no acute GVHD (aGVHD), with grade I skin aGVHD in 1 patient and no aGVHD in the other patient, and no chronic GVHD at 2.1 and 4.1 years post-HCT, respectively. With the approval of eculizumab, the indications for HCT include persistent hemolysis, persistent thrombosis, and associated marrow failure. Administration of eculizumab before and after HCT warrants further study, particularly considering our observation of minimal to no GVHD in 2 patients who received eculizumab after HCT.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Hemoglobinúria Paroxística/mortalidade , Hemoglobinúria Paroxística/terapia , Condicionamento Pré-Transplante , Adolescente , Adulto , Idoso , Aloenxertos , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
15.
Biol Blood Marrow Transplant ; 25(11): 2152-2159, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31255743

RESUMO

Conditioning with fludarabine and low-dose total-body irradiation before allogeneic hematopoietic cell transplantation (HCT) enabled treating older or medically infirm patients with advanced hematologic malignancies in the outpatient setting. Between December 1997 and June 2017, 1037 patients with hematologic malignancies received peripheral blood stem cell (PBSC) grafts from HLA-matched or 1 HLA antigen/allele-mismatched related or unrelated donors. Median age was 58 (range, 18 to 80) years. Serious comorbidities with Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI) scores ≥3 were present in 52% of patients. We found that 47% of patients were either never hospitalized or only had an overnight hospital stay for infusion of late-arriving PBSCs while 53% were admitted for a median of 6 days. Main reasons for admission were infection, fever, graft-versus-host disease, and regimen-related toxicity. Two thirds of admissions occurred within 3 weeks of HCT. The 5-year risk of nonrelapse mortality (NRM) was 26% among hospitalized patients and 13% among nonhospitalized patients. Significant risk factors for hospitalization included unrelated transplants, 1 HLA antigen-mismatched transplant, high HCT-CI scores, and diagnosis of nonmyeloma malignancies. Significant risk factors for NRM were hospitalization, older age, unrelated transplants, and high HCT-CI scores. Ambulatory allogeneic HCT is feasible and safe.


Assuntos
Assistência Ambulatorial , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco de Sangue Periférico , Adolescente , Adulto , Idoso , Aloenxertos , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida
16.
Faraday Discuss ; 216(0): 414-433, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31020294

RESUMO

Electronic and lattice contributions to picosecond time-resolved X-ray absorption spectra (trXAS) of CuO at the oxygen K-edge are analyzed by comparing trXAS spectra, recorded using excitation wavelengths of 355 nm and 532 nm, to steady-state, temperature-dependent XAS measurements. The trXAS spectra at pump-probe time-delays ≥150 ps are dominated by lattice heating effects. Insight into the temporal evolution of lattice temperature profiles on timescales up to 100s of nanoseconds after laser excitation are reported, on an absolute temperature scale, with a temporal sensitivity and a spatial selectivity on the order of 10s of picoseconds and 10s of nanometers, respectively, effectively establishing an "ultrafast thermometer". In particular, for the 532 nm experiment at ∼5 mJ cm-2 fluence, both the initial sample temperature and its dynamic evolution are well captured by a one-dimensional thermal energy deposition and diffusion model. The thermal conductivity k = (1.3 ± 0.4) W m-1 K-1 derived from this model is in good agreement with the literature value for CuO powder, kpowder = 1.013 W m-1 K-1. For 355 nm excitation, a quantitative analysis of the experiments is hampered by the large temperature gradients within the probed sample volume owing to the small UV penetration depth. The impact of the findings on mitigating or utilizing photoinduced lattice temperature changes in future X-ray free electron laser (XFEL) experiments is discussed.

17.
BMC Biol ; 16(1): 147, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30563508

RESUMO

BACKGROUND: The mitochondrial unfolded protein response (mitoUPR) is a stress response pathway activated by disruption of proteostasis in the mitochondria. This pathway has been proposed to influence lifespan, with studies suggesting that mitoUPR activation has complex effects on longevity. RESULTS: Here, we examined the contribution of the mitoUPR to the survival and lifespan of three long-lived mitochondrial mutants in Caenorhabditis elegans by modulating the levels of ATFS-1, the central transcription factor that mediates the mitoUPR. We found that clk-1, isp-1, and nuo-6 worms all exhibit an ATFS-1-dependent activation of the mitoUPR. While loss of atfs-1 during adulthood does not affect lifespan in any of these strains, absence of atfs-1 during development prevents clk-1 and isp-1 worms from reaching adulthood and reduces the lifespan of nuo-6 mutants. Examining the mechanism by which deletion of atfs-1 reverts nuo-6 lifespan to wild-type, we find that many of the transcriptional changes present in nuo-6 worms are mediated by ATFS-1. Genes exhibiting an ATFS-1-dependent upregulation in nuo-6 worms are enriched for transcripts that function in stress response and metabolism. Consistent, with this finding, loss of atfs-1 abolishes the enhanced stress resistance observed in nuo-6 mutants and prevents upregulation of multiple stress response pathways including the HIF-1-mediated hypoxia response, SKN-1-mediated oxidative stress response and DAF-16-mediated stress response. CONCLUSIONS: Our results suggest that in the long-lived mitochondrial mutant nuo-6 activation of the mitoUPR causes atfs-1-dependent changes in the expression of genes involved in stress response and metabolism, which contributes to the extended longevity observed in this mutant. This work demonstrates that the mitoUPR can modulate multiple stress response pathways and suggests that it is crucial for the development and lifespan of long-lived mitochondrial mutants.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Longevidade/genética , Mutação , Estresse Oxidativo/fisiologia , Fatores de Transcrição/genética , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Mitocôndrias , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Resposta a Proteínas não Dobradas
18.
Nat Mater ; 16(3): 335-341, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27820814

RESUMO

Artificial photosystems are advanced by the development of conformal catalytic materials that promote desired chemical transformations, while also maintaining stability and minimizing parasitic light absorption for integration on surfaces of semiconductor light absorbers. Here, we demonstrate that multifunctional, nanoscale catalysts that enable high-performance photoelectrochemical energy conversion can be engineered by plasma-enhanced atomic layer deposition. The collective properties of tailored Co3O4/Co(OH)2 thin films simultaneously provide high activity for water splitting, permit efficient interfacial charge transport from semiconductor substrates, and enhance durability of chemically sensitive interfaces. These films comprise compact and continuous nanocrystalline Co3O4 spinel that is impervious to phase transformation and impermeable to ions, thereby providing effective protection of the underlying substrate. Moreover, a secondary phase of structurally disordered and chemically labile Co(OH)2 is introduced to ensure a high concentration of catalytically active sites. Application of this coating to photovoltaic p+n-Si junctions yields best reported performance characteristics for crystalline Si photoanodes.

19.
Brain Behav Immun ; 67: 364-373, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28988033

RESUMO

Abnormal activation of brain microglial cells is widely implicated in the pathogenesis of schizophrenia. Previously the pathophysiology of microglial activation was considered to be intrinsic to the central nervous system. We hypothesised that due to their perivascular localization, microglia can also be activated by factors present in circulating blood. Through application of high-content functional screening, we show that peripheral blood serum from first-onset drug-naïve schizophrenia patients is sufficient to provoke microglial cell signalling network responses in vitro which are indicative of proinflammatory activation. We further explore the composition of the serum for the presence of analytes, with the potential to activate microglia, and the utility of the resultant microglial cellular phenotype for novel drug discovery.


Assuntos
Inflamação/sangue , Microglia/metabolismo , Esquizofrenia/sangue , Humanos , Inflamação/complicações , Fenótipo , Esquizofrenia/complicações
20.
PLoS Genet ; 11(2): e1004972, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25671321

RESUMO

Reactive oxygen species (ROS) are highly reactive, oxygen-containing molecules that can cause molecular damage within the cell. While the accumulation of ROS-mediated damage is widely believed to be one of the main causes of aging, ROS also act in signaling pathways. Recent work has demonstrated that increasing levels of superoxide, one form of ROS, through treatment with paraquat, results in increased lifespan. Interestingly, treatment with paraquat robustly increases the already long lifespan of the clk-1 mitochondrial mutant, but not other long-lived mitochondrial mutants such as isp-1 or nuo-6. To genetically dissect the subcellular compartment in which elevated ROS act to increase lifespan, we deleted individual superoxide dismutase (sod) genes in clk-1 mutants, which are sensitized to ROS. We find that only deletion of the primary mitochondrial sod gene, sod-2 results in increased lifespan in clk-1 worms. In contrast, deletion of either of the two cytoplasmic sod genes, sod-1 or sod-5, significantly decreases the lifespan of clk-1 worms. Further, we show that increasing mitochondrial superoxide levels through deletion of sod-2 or treatment with paraquat can still increase lifespan in clk-1;sod-1 double mutants, which live shorter than clk-1 worms. The fact that mitochondrial superoxide can increase lifespan in worms with a detrimental level of cytoplasmic superoxide demonstrates that ROS have a compartment specific effect on lifespan - elevated ROS in the mitochondria acts to increase lifespan, while elevated ROS in the cytoplasm decreases lifespan. This work also suggests that both ROS-dependent and ROS-independent mechanisms contribute to the longevity of clk-1 worms.


Assuntos
Envelhecimento/genética , Longevidade/genética , Mitocôndrias/genética , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Envelhecimento/patologia , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Transporte de Elétrons/genética , Complexo III da Cadeia de Transporte de Elétrons/genética , Mitocôndrias/metabolismo , Transdução de Sinais , Superóxido Dismutase/genética , Superóxidos/metabolismo
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