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The intertwining between spin, charge, and lattice degrees of freedom can give rise to unusual macroscopic quantum states, including high-temperature superconductivity and quantum anomalous Hall effects. Recently, a charge density wave (CDW) has been observed in the kagome antiferromagnet FeGe, indicative of possible intertwining physics. An outstanding question is that whether magnetic correlation is fundamental for the spontaneous spatial symmetry breaking orders. Here, utilizing elastic and high-resolution inelastic x-ray scattering, we observe a c-axis superlattice vector that coexists with the 2[Formula: see text]2[Formula: see text]1 CDW vectors in the kagome plane. Most interestingly, between the magnetic and CDW transition temperatures, the phonon dynamical structure factor shows a giant phonon-energy hardening and a substantial phonon linewidth broadening near the c-axis wavevectors, both signaling the spin-phonon coupling. By first principles and model calculations, we show that both the static spin polarization and dynamic spin excitations intertwine with the phonon to drive the spatial symmetry breaking in FeGe.
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The dynamics of a nuclear open quantum system could be revealed in the correlations between the breakup fragments of halo nuclei. The breakup mechanism of a proton halo nuclear system is of particular interest as the Coulomb polarization may play an important role, which, however, remains an open question. Here we use a highly efficient silicon detector array and measure the correlations between the breakup fragments of 8B incident on 120Sn at near-barrier energies. The energy and angular correlations can be explained by a fully quantum mechanical method based on the state-of-the-art continuum discretized coupled channel calculations. The results indicate that, compared to the neutron halo nucleus 6He, 8B presents distinctive reaction dynamics: the dominance of the elastic breakup. This breakup occurs mainly via the short-lived continuum states, almost exhausts the 7Be yield, indicating the effect of Coulomb polarization on the proton halo state. The correlation information reveals that the prompt breakup mechanism dominates, occurring predominantly on the outgoing trajectory. We also show that, as a large environment, the continuum of 8B breakup may not significantly influence elastic scattering and complete fusion.
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Circulating microRNAs (miRNAs) have been used as biomarkers for various diseases and physiological conditions in humans and mice; studies in domestic animals, particularly cattle, are limited. The importance of early pregnancy diagnosis (especially within the 21-d cow estrous cycle) in the livestock industry is extremely high. This study compared the circulating miRNAs in bred non-pregnant and pregnant Japanese Black cows, explored miRNAs as biomarkers for early pregnancy diagnosis, and established a measurement system that included selecting an appropriate reference miRNA and determining the effect of hemolysis on miRNA quantification in plasma. miRNA was extracted from the plasma of Japanese Black cows on day 21 after artificial insemination and subjected to a customized bovine oligonucleotide microarray for expression analysis. Differentially expressed miRNAs and reference miRNA candidates were selected and validated using reverse transcription-quantitative PCR (RT-qPCR). An appropriate endogenous reference miRNA for normalization was selected using NormFinder software. To evaluate the effect of hemolysis on miRNA quantification, hemolyzed samples were prepared using plasma from four cows in the estrous cycle and subjected to RT-qPCR. A total of 124 miRNAs were detected in bovine plasma by microarray analysis in bred non-pregnant and pregnant cows. The levels of five circulating miRNAs were significantly higher in pregnant cows than in bred non-pregnant cows, and 24 miRNAs were detected only in the pregnant group. NormFinder analysis and RT-qPCR validation showed that miR-2455 was an appropriate reference miRNA in the plasma of bred non-pregnant and pregnant Japanese Black cows, and miR-19b, miR-25, miR-29a, and miR-148a were significantly higher in the pregnant group. These four circulating miRNAs did not change during the estrous cycle and were less affected by hemolysis. In the current study, we found four miRNAs, miR-19b, miR-25, miR-29a, and miR-148a, which were present at high levels in the plasma of pregnant Japanese Black cows. Since these miRNAs are less affected by hemolysis, they may potentially be used as biomarkers for early pregnancy diagnosis in cattle.
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MicroRNA Circulante , Animais , Biomarcadores , Bovinos , Feminino , Inseminação Artificial/veterinária , Camundongos , Gravidez , Reação em Cadeia da Polimerase em Tempo Real/veterináriaRESUMO
The anomalous Hall effect (AHE) is an intriguing transport phenomenon occurring typically in ferromagnets as a consequence of broken time reversal symmetry and spin-orbit interaction. It can be caused by two microscopically distinct mechanisms, namely, by skew or side-jump scattering due to chiral features of the disorder scattering, or by an intrinsic contribution directly linked to the topological properties of the Bloch states. Here we show that the AHE can be artificially engineered in materials in which it is originally absent by combining the effects of symmetry breaking, spin orbit interaction and proximity-induced magnetism. In particular, we find a strikingly large AHE that emerges at the interface between a ferromagnetic manganite (La0.7Sr0.3MnO3) and a semimetallic iridate (SrIrO3). It is intrinsic and originates in the proximity-induced magnetism present in the narrow bands of strong spin-orbit coupling material SrIrO3, which yields values of anomalous Hall conductivity and Hall angle as high as those observed in bulk transition-metal ferromagnets. These results demonstrate the interplay between correlated electron physics and topological phenomena at interfaces between 3d ferromagnets and strong spin-orbit coupling 5d oxides and trace an exciting path towards future topological spintronics at oxide interfaces.
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The Kitaev quantum spin liquid epitomizes an entangled topological state, for which two flavors of fractionalized low-energy excitations are predicted: the itinerant Majorana fermion and the Z2 gauge flux. It was proposed recently that fingerprints of fractional excitations are encoded in the phonon spectra of Kitaev quantum spin liquids through a novel fractional-excitation-phonon coupling. Here, we detect anomalous phonon effects in α-RuCl3 using inelastic X-ray scattering with meV resolution. At high temperature, we discover interlaced optical phonons intercepting a transverse acoustic phonon between 3 and 7 meV. Upon decreasing temperature, the optical phonons display a large intensity enhancement near the Kitaev energy, JK~8 meV, that coincides with a giant acoustic phonon softening near the Z2 gauge flux energy scale. These phonon anomalies signify the coupling of phonon and Kitaev magnetic excitations in α-RuCl3 and demonstrates a proof-of-principle method to detect anomalous excitations in topological quantum materials.
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In quantum magnets, magnetic moments fluctuate heavily and are strongly entangled with each other, a fundamental distinction from classical magnetism. Here, with inelastic neutron scattering measurements, we probe the spin correlations of the honeycomb lattice quantum magnet YbCl3. A linear spin wave theory with a single Heisenberg interaction on the honeycomb lattice, including both transverse and longitudinal channels of the neutron response, reproduces all of the key features in the spectrum. In particular, we identify a Van Hove singularity, a clearly observable sharp feature within a continuum response. The demonstration of such a Van Hove singularity in a two-magnon continuum is important as a confirmation of broadly held notions of continua in quantum magnetism and additionally because analogous features in two-spinon continua could be used to distinguish quantum spin liquids from merely disordered systems. These results establish YbCl3 as a benchmark material for quantum magnetism on the honeycomb lattice.
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Balloon occlusion is a potential method for inducing hyperemia to measure post-percutaneous coronary intervention (PCI) fractional flow reserve (FFR). The objective of this study was to determine the clinical usefulness of post-occlusional hyperemia. FFRs measured using post-occlusional hyperemia caused by 30 (FFRoccl30) and 60 s (FFRoccl60) of balloon occlusion after PCI were compared in 60 lesions from 60 patients. The duration of hyperemia was also measured. There was a strong correlation between FFRoccl30 and FFRoccl60 (r = 0.969, p < 0.01). The duration of hyperemia was significantly longer with FFRoccl60 than with FFRoccl30 (68 ± 23 vs. 37 ± 15 s, p < 0.01). The time required for pullback curve analysis was around 45 s. However, in 7 (12%) cases, the duration of hyperemia with FFRoccl60 was < 45 s, which was not enough for pull-back curve analysis. To predict the duration of hyperemia with FFRoccl60 ≥ 45 s, the receiver operating characteristic curve analysis revealed a cut-off value of 25 s of hyperemia with FFRoccl30. FFRoccl30 is sufficient for diagnostic purposes. FFRoccl60 is suitable for pull-back curve analysis in select cases based on predictions made using the duration of hyperemia with FFRoccl30.
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Oclusão com Balão , Estenose Coronária/terapia , Reserva Fracionada de Fluxo Miocárdico , Hiperemia , Intervenção Coronária Percutânea , Trifosfato de Adenosina , Idoso , Oclusão com Balão/métodos , Cateterismo Cardíaco , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de TempoRESUMO
The development of hematopoietic stem cell transplantation (HSCT) programs can face significant challenges in most developing countries because such endeavors must compete with other government health care priorities, including the delivery of basic services. While this is may be a limiting factor, these countries should prioritize development of the needed expertise to offer state of the art treatments including transplantation, by providing financial, technological, legal, ethical and other needed support. This would prove beneficial in providing successful programs customized to the needs of their population, and potentially provide long-term cost-savings by circumventing the need for their citizens to seek care abroad. Costs of establishing HSCT program and the costs of the HSCT procedure itself can be substantial barriers in developing countries. Additionally, socioeconomic factors intrinsic to specific countries can influence access to HSCT, patient eligibility for HSCT and timely utilization of HSCT center capabilities. This report describes recommendations from the Worldwide Network for Blood and Marrow Transplantation (WBMT) for establishing HSCT programs with a specific focus on developing countries, and identifies challenges and opportunities for providing this specialized procedure in the resource constrained setting.
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Transplante de Medula Óssea/métodos , Países em Desenvolvimento/estatística & dados numéricos , Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Humanos , Fatores SocioeconômicosRESUMO
OBJECTIVE: To assess the performance of angiography derived Fractional Flow Reserve (FFRangio) in multivessel disease (MVD) patients undergoing angiography. BACKGROUND: FFR is the reference standard for physiologic assessment of coronary stenosis and guidance of revascularization, especially in patients with MVD, yet it remains grossly underutilized. The non-wire based FFRangio performs well in non-MVD patients, but its accuracy in MVD is unknown. METHODS: A prospective clinical study was conducted at Gifu Heart Centre, Japan. Patients underwent physiologic assessment of all relevant coronary lesions using wire-based FFR (wbFFR) and FFRangio. Primary outcome was diagnostic performance (sensitivity, specificity, accuracy) for FFRangio with wbFFR as reference. Other outcomes were the correlation between wbFFR/FFRangio, time required for wbFFR/FFRangio measurements, and the effect of wbFFR/FFRangio on the reclassification of coronary disease severity. RESULTS: Fifty patients (118 lesions in total) were included. Mean age was 72⯱â¯9â¯years, 72% were male, 36% had triple vessel disease and the average SYNTAX score was 13. The mean measurement of wbFFR and FFRangio were 0.83⯱â¯0.12 and 0.81⯱â¯0.11, respectively. Accuracy, sensitivity and specificity for FFRangio were 92.3% (95% CI 79.1-98.4%), 92.4% (95% CI 84.3-97.2%) and 92.4% (95% CI 87.4-97.3%), respectively. Pearson's r between wbFFR and FFRangio was 0.83. FFRangio measurement was faster than wbFFR (9.6⯱â¯3.4 vs. 15.0⯱â¯8.9â¯min, pâ¯<â¯0.001). CONCLUSIONS: In patients with MVD, FFRangio shows good correlation and excellent diagnostic performance compared to wbFFR, and measuring FFRangio is faster than wbFFR. These results highlight the potential clinical benefits of utilizing FFRangio among patients with MVD.
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Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Idoso , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Índice de Gravidade de DoençaAssuntos
Leucemia Linfocítica Granular Grande/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Neoplasias Cutâneas/metabolismo , Linfócitos T/metabolismo , Medula Óssea/metabolismo , Medula Óssea/patologia , Feminino , Humanos , Leucemia Linfocítica Granular Grande/complicações , Leucemia Linfocítica Granular Grande/patologia , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T gama-delta/genética , Remissão Espontânea , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/patologiaRESUMO
Lipoid pneumonia is an uncommon noninfectious inflammatory lung disease characterized by lipid deposition in the alveoli, and its etiology and treatment have not been elucidated. We report the case of a 32-year-old woman who developed lipoid pneumonia 9 months after allogeneic hematopoietic stem cell transplant for chronic myelogenous leukemia in lymphoid blast crisis. She complained of progressive cough and dyspnea shortly after discontinuation of immunosuppressive therapy given for graft-vs-host disease. Computed tomography demonstrated diffuse ground-glass opacities in the lungs, and pulmonary function test revealed restrictive impairment. Bronchoalveolar lavage fluid showed milky appearance, and transbronchial lung biopsy specimen revealed foamy macrophages infiltrating the alveoli. Based on these findings, she was diagnosed as having lipoid pneumonia. Prednisolone (1 mg/kg/d) promptly improved the symptoms, pulmonary shadows, and pulmonary function. The findings and clinical course of this case suggest that lipoid pneumonia should be recognized as one of the pulmonary complications of allogeneic hematopoietic stem cell transplantation.
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Anti-Inflamatórios/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pneumonia Lipoide/tratamento farmacológico , Pneumonia Lipoide/etiologia , Prednisolona/uso terapêutico , Adulto , Feminino , HumanosRESUMO
Localized spins and itinerant electrons rarely coexist in geometrically-frustrated spinel lattices. They exhibit a complex interplay between localized spins and itinerant electrons. In this paper, we study the origin of the unusual spin structure of the spinel CoV2O4, which stands at the crossover from insulating to itinerant behavior using the first principle calculation and neutron diffraction measurement. In contrast to the expected paramagnetism, localized spins supported by enhanced exchange couplings are frustrated by the effects of delocalized electrons. This frustration produces a non-collinear spin state even without orbital orderings and may be responsible for macroscopic spin-glass behavior. Competing phases can be uncovered by external perturbations such as pressure or magnetic field, which enhances the frustration.
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Although the introduction of tyrosine kinase inhibitors (TKIs) has improved overall survival of patients with chronic myeloid leukemia (CML), about half of the patients eventually relapse after cessation of TKIs. In contrast, the remainder of the patients maintain molecular remission without TKIs, indicating that the patients' immune system could control proliferation of TKI-resistant leukemic stem cells (LSCs). However, the precise mechanism of immunity against CML-LSCs is not fully understood. We have identified a novel immune target, CXorf48, expressed in LSCs of CML patients. Cytotoxic T cells (CTLs) induced by the epitope peptide derived from CXorf48 recognized CD34+CD38- cells obtained from the bone marrow of CML patients. We detected CXorf48-specific CTLs in the peripheral blood mononuclear cells from CML patients who have discontinued imatinib after maintaining complete molecular remission for more than 2 years. Significantly, the relapse rate of CXorf48-specific CTL-negative patients was 63.6%, compared to 0% in CXorf48-specific CTL-positive patients. These results indicate that CXorf48 could be a promising therapeutic target of LSCs for immunotherapy to obtain durable treatment-free remission in CML patients.
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Células da Medula Óssea/imunologia , Linfócitos T CD8-Positivos/imunologia , Regulação Leucêmica da Expressão Gênica/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Proteínas de Neoplasias/imunologia , Células-Tronco Neoplásicas/imunologia , Células da Medula Óssea/patologia , Linfócitos T CD8-Positivos/patologia , Feminino , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Células-Tronco Neoplásicas/patologia , Células THP-1RESUMO
The clinical and genetic spectrum of hereditary sensory and autonomic neuropathy (HSAN) is still unknown in Japan. We collected a broad cohort of 33 unrelated patients with predominant sensory and/or autonomic dysfunctions, who were referred to our genetic laboratory. A gene panel sequencing targeting 18 HSAN-related genes was performed using a next-generation sequencing system. A recurrent frame shift mutation in the WNK1/HSN2 gene, c.3237_3238insT (p.Asp1080*), was detected in 5 patients. This mutation was homozygous in 4 cases and of a compound heterozygous genotype in 1 case. Geographic and haplotype analysis of all 5 patients suggested a founder event. In addition, a novel heterozygous nonsense variant, c.2615C>G (p.Ser872*), was identified. All the 5 patients presented with severe sensory and autonomic dysfunctions at birth or during adolescence. In 2 patients, an uncommon phenotype of acute pathological pain presented at ~50 years of age. Here, we present the first founder mutation of WNK1/HSN2, in addition to French Canadian, which accounts for ~15.2% of Japanese patients with HSAN in our cohort. We have also reviewed all previously described mutations in WNK1/HSN2 and reconciled their nomenclature strategy on the basis of the current longest transcript.
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Códon sem Sentido , Efeito Fundador , Mutação da Fase de Leitura , Neuropatias Hereditárias Sensoriais e Autônomas/genética , Proteína Quinase 1 Deficiente de Lisina WNK/genética , Adulto , Idade de Início , Idoso , Povo Asiático , Estudos de Coortes , Feminino , Expressão Gênica , Haplótipos , Neuropatias Hereditárias Sensoriais e Autônomas/diagnóstico , Neuropatias Hereditárias Sensoriais e Autônomas/etnologia , Neuropatias Hereditárias Sensoriais e Autônomas/fisiopatologia , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BK polyomavirus (BKPyV) is recognized as a pathogen that causes diseases such as hemorrhagic cystitis and nephritis after allogeneic hematopoietic stem cell transplantation (HSCT) or renal transplantation. BKPyV-associated disease is thought to occur through reactivation under immunosuppression. However, the possibility of its nosocomial transmission and the clinical significance of such transmission have not been elucidated. During a 6-month period, nine adult patients (median age: 47 years) who had hematological disorders and who were treated with HSCT (n = 7) or chemotherapy (n = 2) in a single hematology department developed hemorrhagic cystitis due to BKPyV infection. The polymerase chain reaction products of BKPyV DNA obtained from each patient were sequenced. Of the nine patients, six had subtype I, 2 had subtype IV, and 1 had subtype II or III. In the alignment of sequences, four and two of the six subtype I strains were completely homologous (100%). These results strongly suggest that BKPyV has the potential to cause nosocomial infection within a medical facility, especially among recipients of HSCT. Further studies are clearly warranted to elucidate the route(s) of BKPyV transmission in order to establish optimal infection control.
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Falência Renal Crônica/cirurgia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Testes de Função Renal , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Fatores de RiscoRESUMO
The cross sections of the ^{7}Be(n,α)^{4}He reaction for p-wave neutrons were experimentally determined at E_{c.m.}=0.20-0.81 MeV slightly above the big bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s-wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the ^{7}Be(n,α)^{4}He reaction rate is not large enough to solve the cosmological lithium problem, and this conclusion agrees with the recent result from the direct measurement of the s-wave cross sections using a low-energy neutron beam and the evaluated nuclear data library ENDF/B-VII.1.
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OBJECTIVES: Patients with critical limb ischemia (CLI) have poor overall and limb prognosis. Although nutritional status influences overall prognosis, and the Geriatric Nutritional Risk Index (GNRI) is a widely used, simple and well established nutritional status screening method, the association between the GNRI and the overall and limb prognosis of patients with CLI following endovascular therapy (EVT) has not been explored. METHODS: Clinical outcomes were retrospectively evaluated in 473 consecutive patients (74 ± 10 years; 59% male) with CLI who underwent EVT. The GNRI on admission was calculated as follows: [14.89 × albumin (g/dL)] + [41.7 × (body weight/ideal body weight)]. Cox proportional hazard analysis was performed to explore the independent association between the GNRI and mortality and major amputation. RESULTS: Patients (53% ambulatory, 38% wheelchair bound, and 9% bedridden) were divided into two groups based on the median GNRI: the higher group (GNRI ≥ 91.2, n = 237) and the lower group (GNRI < 91.2, n = 236). Median follow up duration after EVT was 11.3 months. Three years after EVT, the survival rate (74% in the higher GNRI, and 48% in the lower GNRI, respectively), and limb salvage rate (92% in the higher GNRI, and 84% in the lower GNRI) were significantly lower in the lower GNRI group. GNRI (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.01-1.05), along with being wheelchair bound (HR, 1.87; 95% CI 1.17-2.97; vs. ambulatory status), being bedridden (HR, 3.10; 95% CI, 1.63-2.97; vs. ambulatory status), being on hemodialysis (HR, 2.33; 95% CI, 1.49-3.64), and having chronic heart failure (HR, 2.22; 95% CI, 1.44-3.43) were the independent predictors of mortality. The GNRI (HR, 1.04; 95% CI, 1.01-1.07), being bedridden (HR, 4.15; 95% CI, 1.67-10.3; vs. ambulatory status), isolated below knee disease (HR, 2.49; 95% CI, 1.30-4.77), and hemodialysis (HR, 2.44; 95% CI, 1.23-4.85) were independently associated with major amputation. CONCLUSIONS: The GNRI on admission was independently associated with mortality and major amputation after EVT in patients with CLI.
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Procedimentos Endovasculares/efeitos adversos , Extremidades/irrigação sanguínea , Avaliação Geriátrica , Isquemia/diagnóstico , Avaliação Nutricional , Idoso , Amputação Cirúrgica/estatística & dados numéricos , Feminino , Humanos , Isquemia/complicações , Isquemia/mortalidade , Masculino , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de RiscoRESUMO
Sinusoidal obstruction syndrome, also known as veno-occlusive disease (SOS/VOD), is a potentially life threatening complication that can develop after hematopoietic cell transplantation. Although SOS/VOD progressively resolves within a few weeks in most patients, the most severe forms result in multi-organ dysfunction and are associated with a high mortality rate (>80%). Therefore, careful attention must be paid to allow an early detection of SOS/VOD, particularly as drugs have now proven to be effective and licensed for its treatment. Unfortunately, current criteria lack sensitivity and specificity, making early identification and severity assessment of SOS/VOD difficult. The aim of this work is to propose a new definition for diagnosis, and a severity-grading system for SOS/VOD in adult patients, on behalf of the European Society for Blood and Marrow Transplantation.
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Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hepatopatia Veno-Oclusiva/diagnóstico , Adulto , Biomarcadores , Diagnóstico Precoce , Hepatopatia Veno-Oclusiva/etiologia , Hepatopatia Veno-Oclusiva/terapia , Humanos , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de DoençaRESUMO
UNLABELLED: Essentials Manufacturing platelets from a donor-independent source is highlighted in transfusion medicine. We examined the differentiation of adipose tissue-derived stromal cells (ASCs) into platelets. Endogenous thrombopoietin (TPO) induced ASCs differentiation into megakaryocytes and platelets. TPO secretion from ASCs was due to an interaction of transferrin with its receptor CD71. SUMMARY: Background Ex vivo production of megakaryocytes (MKs) and platelets from a donor-independent source is currently of intense interest in transfusion medicine. Adipose tissue-derived stromal cells (ASCs) constitute an attractive candidate cell source, because inducing these cells into MK lineages requires no gene transfer and only endogenous transcription factors containing p45NF-E2/Maf, an MK-inducing factor. Objectives To examine whether ASCs differentiate into MK lineages by using endogenous thrombopoietin (TPO), a primary cytokine that drives MK lineages. Methods TPO levels were measured by quantitative real-time PCR and ELISA. To investigate the effects of endogenous TPO on MK and platelet production, surface marker expression and functions for platelets were analyzed in ASC-derived cells cultured in the presence or absence of recombinant TPO. Based on a screening test, the role of transferrin receptor CD71 in TPO production and MK differentiation was examined with anti-CD71 antibody, small interfering RNA (siRNA) against CD71 (siRNA-CD71), and CD71-positive/negative cells. Results ASCs secreted TPO during MK differentiation, and the endogenous TPO facilitated MK and platelet production from ASCs. TPO secretion from ASCs occurred in a transferrin-dependent manner. ASCs treated with anti-CD71 antibody or transfected with siRNA-CD71 produced markedly less TPO. The TPO levels and MK yield were significantly higher when CD71-positive ASCs were used than when CD71-negative ASCs were used. Conclusions CD71 might be an appropriate marker for MK progenitor cells among human ASCs, because of the higher capacity of CD71-positive cells to produce TPO and their ability to differentiate into MKs. These findings could help to establish an efficient method for platelet production.