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1.
Nature ; 592(7854): 381-385, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33820983

RESUMO

Metal halide perovskites of the general formula ABX3-where A is a monovalent cation such as caesium, methylammonium or formamidinium; B is divalent lead, tin or germanium; and X is a halide anion-have shown great potential as light harvesters for thin-film photovoltaics1-5. Among a large number of compositions investigated, the cubic α-phase of formamidinium lead triiodide (FAPbI3) has emerged as the most promising semiconductor for highly efficient and stable perovskite solar cells6-9, and maximizing the performance of this material in such devices is of vital importance for the perovskite research community. Here we introduce an anion engineering concept that uses the pseudo-halide anion formate (HCOO-) to suppress anion-vacancy defects that are present at grain boundaries and at the surface of the perovskite films and to augment the crystallinity of the films. The resulting solar cell devices attain a power conversion efficiency of 25.6 per cent (certified 25.2 per cent), have long-term operational stability (450 hours) and show intense electroluminescence with external quantum efficiencies of more than 10 per cent. Our findings provide a direct route to eliminate the most abundant and deleterious lattice defects present in metal halide perovskites, providing a facile access to solution-processable films with improved optoelectronic performance.

2.
Genes Dev ; 33(7-8): 418-435, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30819820

RESUMO

The RNA polymerase II (RNAPII) C-terminal domain kinase, CDK12, regulates genome stability, expression of DNA repair genes, and cancer cell resistance to chemotherapy and immunotherapy. In addition to its role in mRNA biosynthesis of DNA repair genes, we show here that CDK12 phosphorylates the mRNA 5' cap-binding repressor, 4E-BP1, to promote translation of mTORC1-dependent mRNAs. In particular, we found that phosphorylation of 4E-BP1 by mTORC1 (T37 and T46) facilitates subsequent CDK12 phosphorylation at two Ser-Pro sites (S65 and T70) that control the exchange of 4E-BP1 with eIF4G at the 5' cap of CHK1 and other target mRNAs. RNA immunoprecipitation coupled with deep sequencing (RIP-seq) revealed that CDK12 regulates release of 4E-BP1, and binding of eIF4G, to many mTORC1 target mRNAs, including those needed for MYC transformation. Genome-wide ribosome profiling (Ribo-seq) further identified specific CDK12 "translation-only" target mRNAs, including many mTORC1 target mRNAs as well as many subunits of mitotic and centromere/centrosome complexes. Accordingly, confocal imaging analyses revealed severe chromosome misalignment, bridging, and segregation defects in cells deprived of CDK12 or CCNK. We conclude that the nuclear RNAPII-CTD kinase CDK12 cooperates with mTORC1, and controls a specialized translation network that is essential for mitotic chromosome stability.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Quinase 1 do Ponto de Checagem/genética , Quinases Ciclina-Dependentes/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Instabilidade Genômica/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Quinases Ciclina-Dependentes/genética , Ciclinas/genética , Ciclinas/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Humanos , Mitose/genética , Fosforilação/genética , Ligação Proteica/genética
3.
N Engl J Med ; 388(18): 1668-1679, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-36876735

RESUMO

BACKGROUND: Data regarding clinical outcomes after intravascular imaging-guided percutaneous coronary intervention (PCI) for complex coronary-artery lesions, as compared with outcomes after angiography-guided PCI, are limited. METHODS: In this prospective, multicenter, open-label trial in South Korea, we randomly assigned patients with complex coronary-artery lesions in a 2:1 ratio to undergo either intravascular imaging-guided PCI or angiography-guided PCI. In the intravascular imaging group, the choice between intravascular ultrasonography and optical coherence tomography was at the operators' discretion. The primary end point was a composite of death from cardiac causes, target-vessel-related myocardial infarction, or clinically driven target-vessel revascularization. Safety was also assessed. RESULTS: A total of 1639 patients underwent randomization, with 1092 assigned to undergo intravascular imaging-guided PCI and 547 assigned to undergo angiography-guided PCI. At a median follow-up of 2.1 years (interquartile range, 1.4 to 3.0), a primary end-point event had occurred in 76 patients (cumulative incidence, 7.7%) in the intravascular imaging group and in 60 patients (cumulative incidence, 12.3%) in the angiography group (hazard ratio, 0.64; 95% confidence interval, 0.45 to 0.89; P = 0.008). Death from cardiac causes occurred in 16 patients (cumulative incidence, 1.7%) in the intravascular imaging group and in 17 patients (cumulative incidence, 3.8%) in the angiography group; target-vessel-related myocardial infarction occurred in 38 (cumulative incidence, 3.7%) and 30 (cumulative incidence, 5.6%), respectively; and clinically driven target-vessel revascularization in 32 (cumulative incidence, 3.4%) and 25 (cumulative incidence, 5.5%), respectively. There were no apparent between-group differences in the incidence of procedure-related safety events. CONCLUSIONS: Among patients with complex coronary-artery lesions, intravascular imaging-guided PCI led to a lower risk of a composite of death from cardiac causes, target-vessel-related myocardial infarction, or clinically driven target-vessel revascularization than angiography-guided PCI. (Supported by Abbott Vascular and Boston Scientific; RENOVATE-COMPLEX-PCI ClinicalTrials.gov number, NCT03381872).


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , Angiografia Coronária/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Doença da Artéria Coronariana/etiologia , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção/métodos
4.
Blood ; 143(23): 2425-2432, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38498041

RESUMO

ABSTRACT: The factor V Leiden (FVL; rs6025) and prothrombin G20210A (PTGM; rs1799963) polymorphisms are 2 of the most well-studied genetic risk factors for venous thromboembolism (VTE). However, double heterozygosity (DH) for FVL and PTGM remains poorly understood, with previous studies showing marked disagreement regarding thrombosis risk conferred by the DH genotype. Using multidimensional data from the UK Biobank (UKB) and FinnGen biorepositories, we evaluated the clinical impact of DH carrier status across 937 939 individuals. We found that 662 participants (0.07%) were DH carriers. After adjustment for age, sex, and ancestry, DH individuals experienced a markedly elevated risk of VTE compared with wild-type individuals (odds ratio [OR] = 5.24; 95% confidence interval [CI], 4.01-6.84; P = 4.8 × 10-34), which approximated the risk conferred by FVL homozygosity. A secondary analysis restricted to UKB participants (N = 445 144) found that effect size estimates for the DH genotype remained largely unchanged (OR = 4.53; 95% CI, 3.42-5.90; P < 1 × 10-16) after adjustment for commonly cited VTE risk factors, such as body mass index, blood type, and markers of inflammation. In contrast, the DH genotype was not associated with a significantly higher risk of any arterial thrombosis phenotype, including stroke, myocardial infarction, and peripheral artery disease. In summary, we leveraged population-scale genomic data sets to conduct, to our knowledge, the largest study to date on the DH genotype and were able to establish far more precise effect size estimates than previously possible. Our findings indicate that the DH genotype may occur as frequently as FVL homozygosity and may confer a similarly increased risk of VTE.


Assuntos
Bancos de Espécimes Biológicos , Fator V , Heterozigoto , Protrombina , Humanos , Protrombina/genética , Fator V/genética , Feminino , Masculino , Pessoa de Meia-Idade , Reino Unido/epidemiologia , Idoso , Fatores de Risco , Tromboembolia Venosa/genética , Tromboembolia Venosa/epidemiologia , Adulto , Trombose/genética , Trombose/epidemiologia , Trombose/etiologia , Predisposição Genética para Doença , Genótipo , Polimorfismo de Nucleotídeo Único , Biobanco do Reino Unido
5.
Mol Cell ; 70(5): 920-935.e7, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29883609

RESUMO

Receptor-interacting protein kinase-3 (RIP3 or RIPK3) is a central protein in necroptosis, but posttranslational processes that regulate RIP3 activity and stability remain poorly understood. Here, we identify pellino E3 ubiquitin protein ligase 1 (PELI1) as an E3 ligase that targets RIP3 for proteasome-dependent degradation. Phosphorylation of RIP3 on T182 leads to interaction with the forkhead-associated (FHA) domain of PELI1 and PELI1-mediated K48-linked polyubiquitylation of RIP3 on K363. This same phosphorylation event is also important for RIP3 kinase activity; thus, PELI1 preferentially targets kinase-active RIP3 for degradation. PELI1-mediated RIP3 degradation effectively prevents cell death triggered by RIP3 hyperactivation. Importantly, upregulated RIP3 expression in keratinocytes from toxic epidermal necrolysis (TEN) patients is correlated with low expression of PELI1, suggesting that loss of PELI1 may play a role in the pathogenesis of TEN. We propose that PELI1 may function to control inadvertent activation of RIP3, thus preventing aberrant cell death and maintaining cellular homeostasis.


Assuntos
Queratinócitos/enzimologia , Proteínas Nucleares/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Síndrome de Stevens-Johnson/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Morte Celular , Fibroblastos/enzimologia , Fibroblastos/patologia , Células HEK293 , Células HT29 , Células HeLa , Humanos , Queratinócitos/patologia , Camundongos , Proteínas Nucleares/genética , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteólise , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais , Síndrome de Stevens-Johnson/genética , Síndrome de Stevens-Johnson/patologia , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
6.
Circulation ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39222019

RESUMO

Background: Despite a proposed causal role for low-density lipoprotein cholesterol (LDL-C) in aortic stenosis (AS), randomized controlled trials of lipid-lowering therapy failed to prevent severe AS. We aimed to assess the impact on AS and peak velocity across the aortic valve conferred by lifelong alterations in LDL-C levels mediated by protein-disrupting variants in three clinically significant genes for LDL metabolism (LDLR, APOB, PCSK9). Methods: We utilized sequencing data and electronic health records from UK Biobank (UKB) and All of Us and magnetic resonance imaging data from UKB. We identified predicted protein-disrupting variants with the LOFTEE and AlphaMissense algorithms and evaluated their associations with LDL-C and peak velocity across the aortic valve (UK Biobank), as well as diagnosed AS and aortic valve replacement (UK Biobank + All of Us). Results: We included 421,049 unrelated participants (5,621 with AS) in UKB and 195,519 unrelated participants (1,087 with AS) in All of Us. Carriers of protein-disrupting variants in LDLR had higher mean LDL-C (UKB: +42.6 mg/dl, P=4.4e-237) and greater risk of AS (meta-analysis: odds ratio [OR] =3.52 [95% CI 2.39-5.20], P=2.3e-10) and aortic valve replacement (meta-analysis: OR=3.78 [95% CI 2.26-6.32], P=4.0e-7). Carriers of protein-disrupting variants in APOB or PCSK9 had lower mean LDL-C (UKB: -32.3 mg/dl, P<5e-324) and lower risk of AS (meta-analysis: OR=0.49 [0.31-0.75], P=0.001) and aortic valve replacement (meta-analysis: OR=0.54 [0.30-0.97], P=0.04). Among 57,371 UKB imaging substudy participants, peak velocities across the aortic valve were greater in carriers of protein-disrupting variants in LDLR (+12.2cm/s, P=1.6e-5) and lower in carriers of protein-disrupting variants in PCSK9 (-6.9cm/s, P=0.022). Conclusions: Rare genetic variants that confer lifelong higher or lower LDL-C levels are associated with substantially increased and decreased risk of AS, respectively. Early and sustained lipid-lowering therapy may slow or prevent AS development.

7.
J Immunol ; 210(5): 558-567, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36645445

RESUMO

Systemic lupus erythematosus is a complex autoimmune disease with significant morbidity that demands further examination of tolerance-inducing treatments. Short-term treatment of lupus-prone NZB/WF1 mice with combination CTLA4Ig and anti-CD40 ligand, but not single treatment alone, suppresses disease for >6 mo via modulation of B and T cell function while maintaining immune responses to exogenous Ags. Three months after a 2-wk course of combination costimulatory blockade, we found a modest decrease in the number of activated T and B cells in both combination and single-treatment cohorts compared with untreated controls. However, only combination treatment mice showed a 50% decrease in spare respiratory capacity of splenic B and T cells. RNA sequencing and gene set enrichment analysis of germinal center (GC) B cells confirmed a reduction in the oxidative phosphorylation signature in the combination treatment cohort. This cohort also manifested increased expression of BCR-associated signaling molecules and increased phosphorylation of PLCγ in GC B cells after stimulation with anti-IgG and anti-CD40. GC B cells from combination treatment mice also displayed a signature involving remodeling of GPI-linked surface proteins. Accordingly, we found a decrease in cell surface expression of the inhibitory molecule CD24 on class-switched memory B cells from aged NZB/W mice that corrected in the combination treatment cohort. Because both a profound decrease in BCR signaling and remodeled immune cell metabolism enhance loss of tolerance in lupus-prone mice, our findings help to explain the restoration of tolerance observed after short-term combination costimulatory blockade.


Assuntos
Ligante de CD40 , Lúpus Eritematoso Sistêmico , Animais , Camundongos , Ligantes , Metaboloma , Camundongos Endogâmicos NZB , Receptores de Antígenos de Linfócitos B , Abatacepte
8.
J Immunol ; 211(5): 727-734, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37486226

RESUMO

Pre-B cell leukemia homeobox 1 (PBX1) controls chromatin accessibility to a large number of genes in various cell types. Its dominant negative splice isoform, PBX1D, which lacks the DNA and Hox-binding domains, is expressed more frequently in the CD4+ T cells from lupus-prone mice and patients with systemic lupus erythematosus than healthy control subjects. PBX1D overexpression in CD4+ T cells impaired regulatory T cell homeostasis and expanded inflammatory CD4+ T cells. In this study, we showed that PBX1 message expression is downregulated by activation in CD4+ T cells as well as in B cells. PBX1D protein was less stable than the normal isoform, PBX1B, and it is degraded through the ubiquitin-proteasome-dependent pathway. The DNA binding domain lacking in PBX1D has two putative ubiquitin binding sites, K292 and K293, that are predicted to be in direct contact with DNA. Mutation of K292-293 reduced PBX1B stability to a level similar to PBX1D and abrogated DNA binding. In addition, contrary to PBX1B, PBX1D is retained in the cytoplasm without the help of the cofactors MEIS or PREP1, indicating a different requirement for nuclear translocation. Overall, these findings suggest that multiple post-transcriptional mechanisms are responsible for PBX1D loss of function and induction of CD4+ T cell inflammatory phenotypes in systemic lupus erythematosus.


Assuntos
Proteínas de Homeodomínio , Lúpus Eritematoso Sistêmico , Camundongos , Animais , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Fator de Transcrição 1 de Leucemia de Células Pré-B/genética , Alelos , Isoformas de Proteínas/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/metabolismo , DNA , Ubiquitinas/genética
9.
J Immunol ; 210(4): 377-388, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36602759

RESUMO

The activation of lymphocytes in patients with lupus and in mouse models of the disease is coupled with an increased cellular metabolism in which glucose plays a major role. The pharmacological inhibition of glycolysis with 2-deoxy-d-glucose (2DG) reversed the expansion of follicular helper CD4+ T cells and germinal center B cells in lupus-prone mice, as well as the production of autoantibodies. The response of foreign Ags was however not affected by 2DG in these mice, suggesting that B and CD4+ T cell activation by autoantigens is uniquely sensitive to glycolysis. In this study, we tested this hypothesis with monoclonal B cells and CD4+ T cells specific for lupus-relevant autoantigens. AM14 Vκ8R (AM14) transgenic B cells are activated by IgG2a/chromatin immune complexes and they can receive cognate help from chromatin-specific 13C2 CD4+ T cells. We showed that activation of AM14 B cells by their cognate Ag PL2-3 induced glycolysis, and that the inhibition of glycolysis reduced their activation and differentiation into Ab-forming cells, in the absence or presence of T cell help. The dependency of autoreactive B cells on glycolysis is in sharp contrast with the previously reported dependency of 4-hydroxy-3-nitrophenyl acetyl-specific B cells on fatty acid oxidation. Contrary to AM14 B cells, the activation and differentiation of 13C2 T cells into follicular helper CD4+ T cells was not altered by 2DG, which differs from polyclonal CD4+ T cells from lupus-prone mice. These results further define the role of glycolysis in the production of lupus autoantibodies and demonstrate the need to evaluate the metabolic requirements of Ag-specific B and T cells.


Assuntos
Linfócitos T CD4-Positivos , Lúpus Eritematoso Sistêmico , Linfoma de Células B , Animais , Camundongos , Autoanticorpos , Autoantígenos/metabolismo , Cromatina/metabolismo , Glucose/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Ativação Linfocitária , Linfócitos T Auxiliares-Indutores
10.
Chem Soc Rev ; 53(16): 8137-8181, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39021095

RESUMO

Hydrogen peroxide (H2O2) is a highly desired chemical with a wide range of applications. Recent advancements in H2O2 synthesis center on the electrochemical reduction of oxygen, an environmentally friendly approach that facilitates on-site production. To successfully implement practical-scale, highly efficient electrosynthesis of H2O2, it is critical to meticulously explore both the design of catalytic materials and the engineering of other components of the electrochemical system, as they hold equal importance in this process. Development of promising electrocatalysts with outstanding selectivity and activity is a prerequisite for efficient H2O2 electrosynthesis, while well-configured electrolyzers determine the practical implementation of large-scale H2O2 production. In this review, we systematically summarize fundamental mechanisms and recent achievements in H2O2 electrosynthesis, including electrocatalyst design, electrode optimization, electrolyte engineering, reactor exploration, potential applications, and integrated systems, with an emphasis on active site identification and microenvironment regulation. This review also proposes new insights into the existing challenges and opportunities within this rapidly evolving field, together with perspectives on future development of H2O2 electrosynthesis and its industrial-scale applications.

11.
J Am Chem Soc ; 146(32): 22387-22395, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39088737

RESUMO

Preventing ion migration in perovskite photovoltaics is key to achieving stable and efficient devices. The activation energy for ion migration is affected by the chemical environment surrounding the ions. Thus, the migration of organic cations in lead halide perovskites can be mitigated by engineering their local interactions, for example through hydrogen bonding. Ion migration also leads to ionic losses via interfacial reactions. Undesirable reactivities of the organic cations can be eliminated by introducing protecting groups. In this work, we report bis(2-oxo-3-oxazolidinyl) phosphinic chloride (BOP-Cl) as a perovskite ink additive with the following benefits: (1) The phosphoryl and two oxo groups form six-membered intermolecular hydrogen-bonded rings with the formamidinium cation (FA), mitigating ion migrations. (2) The hydrogen bonding reduces the electrophilicity of the ammonium protons by donating electron density, therefore reducing its reactivity with the surface oxygen on the metal oxide. Furthermore, the molecule can react to form a protecting group on the nucleophilic oxygen at the tin oxide transport layer surface through the elimination of chlorine. As a result, we achieve perovskite solar cells with an efficiency of 25.0% and improved MPP stability T93 = 1200 h at 40-45 °C compared to a control device (T86 = 550 h). In addition, we show a negative correlation between the strength of hydrogen bonding of different phosphine oxide derivatives to the organic cations and the degree of metastable behavior (e.g., initial burn-in) of the device.

12.
Radiology ; 311(2): e233120, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38713025

RESUMO

Background According to 2021 World Health Organization criteria, adult-type diffuse gliomas include glioblastoma, isocitrate dehydrogenase (IDH)-wildtype; oligodendroglioma, IDH-mutant and 1p/19q-codeleted; and astrocytoma, IDH-mutant, even when contrast enhancement is lacking. Purpose To develop and validate simple scoring systems for predicting IDH and subsequent 1p/19q codeletion status in gliomas without contrast enhancement using standard clinical MRI sequences. Materials and Methods This retrospective study included adult-type diffuse gliomas lacking contrast at contrast-enhanced MRI from two tertiary referral hospitals between January 2012 and April 2022 with diagnoses confirmed at pathology. IDH status was predicted primarily by using T2-fluid-attenuated inversion recovery (FLAIR) mismatch sign, followed by 1p/19q codeletion prediction. A visual rating of MRI features, apparent diffusion coefficient (ADC) ratio, and relative cerebral blood volume was measured. Scoring systems were developed through univariable and multivariable logistic regressions and underwent calibration and discrimination, including internal and external validation. Results For the internal validation cohort, 237 patients were included (mean age, 44.4 years ± 14.4 [SD]; 136 male patients; 193 patients in IDH prediction and 163 patients in 1p/19q prediction). For the external validation cohort, 35 patients were included (46.1 years ± 15.3; 20 male patients; 28 patients in IDH prediction and 24 patients in 1p/19q prediction). The T2-FLAIR mismatch sign demonstrated 100% specificity and 100% positive predictive value for IDH mutation. IDH status prediction scoring system for tumors without mismatch sign included age, ADC ratio, and morphologic characteristics, whereas 1p/19q codeletion prediction for IDH-mutant gliomas included ADC ratio, cortical involvement, and mismatch sign. For IDH status and 1p/19q codeletion prediction, bootstrap-corrected areas under the receiver operating characteristic curve were 0.86 (95% CI: 0.81, 0.90) and 0.73 (95% CI: 0.65, 0.81), respectively, whereas at external validation they were 0.99 (95% CI: 0.98, 1.0) and 0.88 (95% CI: 0.63, 1.0). Conclusion The T2-FLAIR mismatch sign and scoring systems using standard clinical MRI predicted IDH and 1p/19q codeletion status in gliomas lacking contrast enhancement. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Badve and Hodges in this issue.


Assuntos
Deleção Cromossômica , Isocitrato Desidrogenase , Imageamento por Ressonância Magnética , Mutação , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/diagnóstico por imagem , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 19/genética , Meios de Contraste , Glioma/genética , Glioma/diagnóstico por imagem , Isocitrato Desidrogenase/genética , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
13.
Radiology ; 310(3): e230701, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38501951

RESUMO

Background Blood-brain barrier (BBB) permeability change is a possible pathologic mechanism of autoimmune encephalitis. Purpose To evaluate the change in BBB permeability in patients with autoimmune encephalitis as compared with healthy controls by using dynamic contrast-enhanced (DCE) MRI and to explore its predictive value for treatment response in patients. Materials and Methods This single-center retrospective study included consecutive patients with probable or possible autoimmune encephalitis and healthy controls who underwent DCE MRI between April 2020 and May 2021. Automatic volumetric segmentation was performed on three-dimensional T1-weighted images, and volume transfer constant (Ktrans) values were calculated at encephalitis-associated brain regions. Ktrans values were compared between the patients and controls, with adjustment for age and sex with use of a nonparametric approach. The Wilcoxon rank sum test was performed to compare Ktrans values of the good (improvement in modified Rankin Scale [mRS] score of at least two points or achievement of an mRS score of ≤2) and poor (improvement in mRS score of less than two points and achievement of an mRS score >2) treatment response groups among the patients. Results Thirty-eight patients with autoimmune encephalitis (median age, 38 years [IQR, 29-59 years]; 20 [53%] female) and 17 controls (median age, 71 years [IQR, 63-77 years]; 12 [71%] female) were included. All brain regions showed higher Ktrans values in patients as compared with controls (P < .001). The median difference in Ktrans between the patients and controls was largest in the right parahippocampal gyrus (25.1 × 10-4 min-1 [95% CI: 17.6, 43.4]). Among patients, the poor treatment response group had higher baseline Ktrans values in both cerebellar cortices (P = .03), the left cerebellar cortex (P = .02), right cerebellar cortex (P = .045), left cerebral cortex (P = .045), and left postcentral gyrus (P = .03) than the good treatment response group. Conclusion DCE MRI demonstrated that BBB permeability was increased in all brain regions in patients with autoimmune encephalitis as compared with controls, and baseline Ktrans values were higher in patients with poor treatment response in the cerebellar cortex, left cerebral cortex, and left postcentral gyrus as compared with the good response group. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Filippi and Rocca in this issue.


Assuntos
Doenças Autoimunes do Sistema Nervoso , Encefalite , Doença de Hashimoto , Humanos , Feminino , Adulto , Idoso , Masculino , Permeabilidade Capilar , Estudos Retrospectivos , Encefalite/diagnóstico por imagem , Imageamento por Ressonância Magnética
14.
Small ; 20(32): e2309744, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38507730

RESUMO

The development of hydrogen (H2) gas sensors is essential for the safe and efficient adoption of H2 gas as a clean, renewable energy source in the challenges against climate change, given its flammability and associated safety risks. Among various H2 sensors, gasochromic sensors have attracted great interest due to their highly intuitive and low power operation, but slow kinetics, especially slow recovery rate limited its further practical application. This study introduces Pd-decorated amorphous WO3 nanorods (Pd-WO3 NRs) as an innovative gasochromic H2 sensor, demonstrating rapid and highly reversible color changes for H2 detection. In specific, the amorphous nanostructure exhibits notable porosity, enabling rapid detection and recovery by facilitating effective H2 gas interaction and efficient diffusion of hydrogen ions (H+) dissociated from the Pd nanoparticles (Pd NPs). The optimized Pd-WO3 NRs sensor achieves an impressive response time of 14 s and a recovery time of 1 s to 5% H2. The impressively fast recovery time of 1 s is observed under a wide range of H2 concentrations (0.2-5%), making this study a fundamental solution to the challenged slow recovery of gasochromic H2 sensors.

15.
Mol Ecol ; : e17422, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842022

RESUMO

During hybrid speciation, homoeologues combine in a single genome. Homoeologue expression bias (HEB) occurs when one homoeologue has higher gene expression than another. HEB has been well characterized in plants but rarely investigated in animals, especially invertebrates. Consequently, we have little idea as to the role that HEB plays in allopolyploid invertebrate genomes. If HEB is constrained by features of the parental genomes, then we predict repeated evolution of similar HEB patterns among hybrid genomes formed from the same parental lineages. To address this, we reconstructed the history of hybridization between the New Zealand stick insect genera Acanthoxyla and Clitarchus using a high-quality genome assembly from Clitarchus hookeri to call variants and phase alleles. These analyses revealed the formation of three independent diploid and triploid hybrid lineages between these genera. RNA sequencing revealed a similar magnitude and direction of HEB among these hybrid lineages, and we observed that many enriched functions and pathways were also shared among lineages, consistent with repeated evolution due to parental genome constraints. In most hybrid lineages, a slight majority of the genes involved in mitochondrial function showed HEB towards the maternal homoeologues, consistent with only weak effects of mitonuclear incompatibility. We also observed a proteasome functional enrichment in most lineages and hypothesize this may result from the need to maintain proteostasis in hybrid genomes. Reference bias was a pervasive problem, and we caution against relying on HEB estimates from a single parental reference genome.

16.
BMC Cancer ; 24(1): 909, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075471

RESUMO

BACKGROUND: Advancements in the diagnosis, treatment, and surveillance of castration-resistant prostate cancer (CRPC) have progressed considerably, but a new biomarker that combines existing clinical and pathological data could be useful for a more precise diagnosis and prognosis. Some investigations have found that extracellular vesicle (EV)-derived miRNAs play crucial roles in various types of malignant tumors. The objective of this study was to explore EV miRNA and identify its biologic function as a biomarker for the diagnosis and prognosis of CRPC. METHODS: Plasma samples were collected from five healthy donors (Control, CT) and 17 CRPC patients, categorizing into two groups based on their endocrine treatment response: partial response (PR; n = 10) and progressive disease (PD; n = 7). Candidate extracellular vesicle (EV) miRNAs were identified using miRNA microarray and RT-qPCR. The biological functions of the selected miRNAs were evaluated using the MTT assay, wound healing assay, trans-well assay, and RNA sequencing in CRPC cells after transient miRNA expression. RESULTS: Microarray analysis revealed a significant downregulation of EV-miR-6880-5p in the PD samples compared to both CT and PR samples (p < 0.01). The expression of EV-miR-6880-5p in CRPC patients was decreased compared with that CT group (p = 0.0336) using RT-qPCR. In the PR group, EV-miR-6880-5p was increased at follow-up compared with the baseline (p = 0.2803), while in the PD group, it decreased at follow-up compared with the baseline samples (p = 0.4356). Furthermore, overexpression of miR-6880-5p hampered cell proliferation, migration, and invasion, downregulated pathways associated with tumor progression, and simultaneously upregulated pathways associated with cell growth and apoptosis in CRPC cells. CONCLUSIONS: EV-miR-6880-5p shows promise as a prognostic biomarker in patients with CRPC. Further, prospective validations are necessary to evaluate the potential of these candidate miRNAs.


Assuntos
Biomarcadores Tumorais , Vesículas Extracelulares , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , MicroRNAs/sangue , MicroRNAs/genética , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Prognóstico , Idoso , Pessoa de Meia-Idade , Linhagem Celular Tumoral , Proliferação de Células , Perfilação da Expressão Gênica/métodos , Movimento Celular/genética
17.
J Magn Reson Imaging ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39238277

RESUMO

BACKGROUND: The specific patterns of subependymal enhancement (SE) that frequently occur as radiation-induced changes in high-grade gliomas following radiotherapy are often overlooked. Perfusion MRI may offer a diagnostic clue. PURPOSE: To distinguish between radiation-induced SE and progression in adult high-grade diffuse gliomas after standard treatment. STUDY TYPE: Retrospective. POPULATION: Ninety-four consecutive high-grade diffuse glioma patients (mean age, 55 ± 14 years; 54 [57.4%] males) with new SE identified in follow-up MRI after completion of surgery plus chemoradiation: progression (N = 74) vs. regression (N = 20). FIELD STRENGTH/SEQUENCE: 3 T, gradient-echo dynamic susceptibility contrast-enhanced MRI, 3D gradient-echo contrast-enhanced T1-weighted imaging. ASSESSMENT: To differentiate between radiation changes and progression in SE evaluation, multivariable logistic regression was performed using significant variables among SE appearance interval, IDH mutation, morphological features, and rCBV. Cox regression was performed to predict the tumor progression. For the added value of the rCBV, a log-rank test was conducted between the multivariable logistic regression models with and without the rCBV. STATISTICAL TESTS: Logistic regression, Cox regression, receiver operating characteristic analysis, log-rank test. RESULTS: 38.3% (36/94) patients had first specific SE (9.2 ± 9.5 months after surgery), which disappeared in 21.3% (20/94) after 5.8 ± 5.8 months after initial appearance on post-radiation MRI. IDH mutation, elongated, small lesions with lower rCBV tended to regress: IDH mutation, elongation, diameter, and rCBV_p95; odds ratio, 0.32, 1.92, 1.70, and 2.47, respectively. Qualitative evaluation of shape revealed that thin and curvilinear-shaped SE tended to regress, indicating a significant correlation with quantitative shape features (r = 0.31). In Cox regression, rCBV and lesion shape were significant (hazard ratio = 1.09 and 0.54, respectively). For sub-centimeter lesions, the rCBV showed added value in predicting outcomes (area under the curve, 0.873 vs. 0.836; log-rank test). DATA CONCLUSION: Smaller, elongated lesions with lower rCBV and IDH mutation are associated with regression when differentiating radiation changes from progression in high-grade glioma with post-radiotherapy SE. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

18.
Transfusion ; 64(3): 467-474, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38264767

RESUMO

BACKGROUND: Bleeding after cardiac surgery is common and continues to require 10-20% of the national blood supply. Transfusion of allogeneic blood is associated with increased morbidity and mortality. Excessive protamine in the absence of circulating heparin after weaning off CPB can cause anticoagulation and precipitate bleeding. Hence, adequate dose calculation of protamine is crucial yet under evaluated. STUDY DESIGN: Retrospective cohort study. METHODS: We conducted a retrospective bi-institutional analysis of cardiac surgical patients who underwent cardiopulmonary bypass (CPB)-assisted cardiac surgery to assess the impact of protamine dosing in transfusion practice. Total 762 patients were identified from two institutions using electronic medical records and the Society of Thoracic Surgery (STS) database who underwent cardiac surgery using CPB. Patients were similar in demographics and other baseline characteristics. We divided patients into two groups based on mg of protamine administered to neutralize each 100 U of unfractionated heparin (UFH)-low-ratio group (Protamine: UFH ≤ 0.8) and high-ratio group (Protamine: UFH > 0.8). RESULTS: We observed a higher rate of blood transfusion required in high-ratio group (ratio >0.8) compared with low-ratio group (ratio ≤0.8) (p < .001). The increased requirement was consistently demonstrated for intraoperative transfusions of red blood cells, plasma, platelets, and cryoprecipitate. CONCLUSION: High protamine to heparin ratio may cause increased bleeding and transfusion in cardiac surgical patients. Protamine to heparin ratio of 0.8 or lower is sufficient to neutralize circulating heparin after weaning off cardiopulmonary bypass.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cirurgia Torácica , Humanos , Heparina , Protaminas/uso terapêutico , Estudos Retrospectivos , Transfusão de Sangue , Ponte Cardiopulmonar , Anticoagulantes/uso terapêutico , Antagonistas de Heparina
19.
Chemphyschem ; 25(17): e202400333, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38777788

RESUMO

We fabricated MAPbI3 perovskite thin films with ZnO on a glass substrate, in which a passivation layer (Phenethylammonium iodide (PEAI); p-methoxyphenethylammonium iodide (CH3O-PEAI); 2-methoxyethylammonium iodide (MEAI)) was inserted between two layers. In order to understand the effect of the insertion of each passivation material on the transfer efficiency of the photo-generated electrons from MAPbI3 to ZnO, we observed the near-field heterodyne transient grating (NF-HD-TG) responses of each film and investigated the component arising from the recombination of the trapped electrons at the ZnO surface. Based on the accelerated recombination between photo-generated holes remaining in the MAPbI3 layer and surface-trapped electrons in ZnO and the increase in the number of the trapped electrons in ZnO when either CH3O-PEAI or PEAI was applied, we successfully revealed that the charge transfer efficiency was enhanced by the insertion of the passivation materials including a benzene ring stabilizing the defect states. Particularly, it was demonstrated that CH3O-PEAI showed the highest increase in the charge transfer efficiency, which could be attributed to the high electron density in the benzene ring, resulting from the existence of the electron donating group, CH3O, and its role in the effective transition from 3D to 2D perovskite phases.

20.
Nanotechnology ; 35(27)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38522102

RESUMO

To obtain high-quality SiNxfilms applicable to an extensive range of processes, such as gate spacers in fin field-effect transistors (FinFETs), the self-aligned quadruple patterning process, etc, a study of plasma with higher plasma density and lower plasma damage is crucial in addition to study on novel precursors for SiNxplasma-enhanced atomic layer deposition (PEALD) processes. In this study, a novel magnetized PEALD process was developed for depositing high-quality SiNxfilms using di(isopropylamino)silane (DIPAS) and magnetized N2plasma at a low substrate temperature of 200 °C. The properties of the deposited SiNxfilms were analyzed and compared with those obtained by the PEALD process using a non-magnetized N2plasma source under the same conditions. The PEALD SiNxfilm, produced using an external magnetic field (ranging from 0 to 100 G) during the plasma exposure step, exhibited a higher growth rate (∼1 Å/cycle) due to the increased plasma density. Additionally, it showed lower surface roughness, higher film density, and enhanced wet etch resistance compared to films deposited using the PEALD process with non-magnetized plasmas. This improvement can be attributed to the higher ion flux and lower ion energy of the magnetized plasma. The electrical characteristics, such as interface trap density and breakdown voltage, were also enhanced when the magnetized plasma was used for the PEALD process. Furthermore, when SiNxfilms were deposited on high-aspect-ratio (30:1) trench patterns using the magnetized PEALD process, an improved step coverage of over 98% was achieved, in contrast to the conformality of SiNxdeposited using non-magnetized plasma. This enhancement is possibly a result of deeper radical penetration enabled by the magnetized plasma.

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