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1.
Hepatology ; 76(6): 1690-1705, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35229337

RESUMO

BACKGROUND AND AIMS: Hepatocyte transplantation has been demonstrated to be effective to treat liver metabolic disease and acute liver failure. Nevertheless, the shortage of donor hepatocytes restrained its application in clinics. To expand human hepatocytes at a large scale, several dedifferentiation-based protocols have been established, including proliferating human hepatocytes (ProliHH). However, the decreased transplantation efficiency of these cells after long-term expansion largely impedes their application. APPROACH AND RESULTS: We found that accompanied with dedifferentiation, long-term cultured ProliHH (lc-ProliHH) up-regulated a panel of chemokines and cytokines related to innate immunity, which were referred to as dedifferentiation-associated inflammatory factors (DAIF). DAIF elicited excessive macrophage responses, accounting for the elimination of lc-ProliHH specifically during engraftment. Two possible strategies to increase ProliHH transplantation were then characterized. Blockage of innate immune response by dexamethasone reverted the engraftment and repopulation of lc-ProliHH to a level comparable to primary hepatocytes, resulting in improved liver function and a better survival of fumarylacetoacetate hydrolase-deficient mice. Alternatively, rematuration of lc-ProliHH as organoids reduced the expression of DAIF and led to markedly improved engraftment. CONCLUSIONS: These results revealed that lc-ProliHH triggers exacerbated macrophage activation by DAIF and provided potential solutions for clinical transplantation of lc-ProliHH.


Assuntos
Hepatócitos , Fígado , Humanos , Camundongos , Animais , Hepatócitos/metabolismo , Fígado/metabolismo , Citocinas/metabolismo , Quimiocinas/metabolismo , Macrófagos/metabolismo
2.
Phys Chem Chem Phys ; 25(17): 12342-12351, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37089106

RESUMO

Elucidating the mechanism of aggregation-induced emission (AIE) is a prerequisite for designing more AIE-gens. The diphenylethylene (DPE) featured molecules are one of the most important AIE-gens due to their propeller structure. Three representative DPE-featured AIE-gens, triphenylethylene, cis-stilbene, and trans-stilbene, are explored via ultrafast ultraviolet/infrared (UV/IR) spectroscopy and theoretical calculations. Both experimental and computational results suggest that readily crossing conical intersections (CIs) with flexible structural evolutions in solutions significantly reduces fluorescence, whereas crossing CIs is restricted because of high energy cost, and therefore no fast nonradiative decay can compete with spontaneous emission in solids. The mechanism also well explains the different emission quantum yields and interconversion ratios between cis-stilbene and trans-stilbene after photoexcitation.

3.
Acc Chem Res ; 54(23): 4215-4228, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34756027

RESUMO

Nonadiabatic dynamical processes are one of the most important quantum mechanical phenomena in chemical, materials, biological, and environmental molecular systems, where the coupling between different electronic states is either inherent in the molecular structure or induced by the (intense) external field. The curse of dimensionality indicates the intractable exponential scaling of calculation effort with system size and restricts the implementation of "numerically exact" approaches for realistic large systems. The phase space formulation of quantum mechanics offers an important theoretical framework for constructing practical approximate trajectory-based methods for quantum dynamics. This Account reviews our recent progress in phase space mapping theory: a unified framework for constructing the mapping Hamiltonian on phase space for coupled F-state systems where the renowned Meyer-Miller Hamiltonian model is a special case, a general phase space formulation of quantum mechanics for nonadiabatic systems where the electronic degrees of freedom are mapped onto constraint space and the nuclear degrees of freedom are mapped onto infinite space, and an isomorphism between the mapping phase space approach for nonadiabatic systems and that for nonequilibrium electron transport processes. While the zero-point-energy parameter is conventionally assumed to be positive, we show that the constraint implied in the conventional Meyer-Miller mapping Hamiltonian requires that such a parameter can be negative as well and lies in (-1/F, +∞) for each electronic degree of freedom. More importantly, the zero-point-energy parameter should be interpreted as a special case of a commutator matrix in the comprehensive phase space mapping Hamiltonian for nonadiabatic systems. From the rigorous formulation of mapping phase space, we propose approximate but practical trajectory-based nonadiabatic dynamics methods. The applications to both gas phase and condensed phase problems include the spin-boson model for condensed phase dissipative two-state systems, the three-state photodissociation models, the seven-site model of the Fenna-Matthews-Olson monomer in photosynthesis of green sulfur bacteria, the strongly coupled molecular/atomic matter-optical cavity systems designed for controlling and manipulating chemical dynamical processes, and the Landauer model for a quantum dot state coupled with two electrodes. In these applications the overall performance of our phase space mapping dynamics approach is superior to two prevailing trajectory-based methods, Ehrenfest dynamics and fewest switches surface hopping.

4.
J Phys Chem A ; 125(31): 6845-6863, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34339600

RESUMO

We show that a novel, general phase space mapping Hamiltonian for nonadiabatic systems, which is reminiscent of the renowned Meyer-Miller mapping Hamiltonian, involves a commutator variable matrix rather than the conventional zero-point-energy parameter. In the exact mapping formulation on constraint space for phase space approaches for nonadiabatic dynamics, the general mapping Hamiltonian with commutator variables can be employed to generate approximate trajectory-based dynamics. Various benchmark model tests, which range from gas phase to condensed phase systems, suggest that the overall performance of the general mapping Hamiltonian is better than that of the conventional Meyer-Miller Hamiltonian.

6.
J Phys Chem Lett ; 15(2): 644-658, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38205956

RESUMO

Nonadiabatic transition dynamics lies at the core of many electron/hole transfer, photoactivated, and vacuum field-coupled processes. About a century after Ehrenfest proposed "Phasenraum" and the Ehrenfest theorem, we report a conceptually novel trajectory-based nonadiabatic dynamics approach, nonadiabatic field (NAF), based on a generalized exact coordinate-momentum phase space formulation of quantum mechanics. It does not employ the conventional Born-Oppenheimer or Ehrenfest trajectory in the nonadiabatic coupling region. Instead, in NAF the equations of motion of the independent trajectory involve a nonadiabatic nuclear force term in addition to an adiabatic nuclear force term of a single electronic state. A few benchmark tests for gas phase and condensed phase systems indicate that NAF offers a practical tool to capture the correct correlation of electronic and nuclear dynamics for processes where the states remain coupled all the time as well as for the asymptotic region where the coupling of electronic states vanishes.

7.
J Phys Chem Lett ; 15(20): 5452-5466, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38747729

RESUMO

Recent progress on the constraint coordinate-momentum phase space (CPS) formulation of finite-state quantum systems has revealed that the triangle window function approach is an isomorphic representation of the exact population-population correlation function of the two-state system. We use the triangle window (TW) function and the CPS mapping kernel element to formulate a novel useful representation of discrete electronic degrees of freedom (DOFs). When it is employed with nonadiabatic field (NaF) dynamics, a new variant of the NaF approach (i.e., NaF-TW) is proposed. The NaF-TW expression of the population of any adiabatic state is always positive semidefinite. Extensive benchmark tests of model systems in both the condensed phase and gas phase demonstrate that the NaF-TW approach is able to faithfully capture the dynamical interplay between electronic and nuclear DOFs in a broad region, including where the states remain coupled all the time, as well as where the bifurcation characteristic of nuclear motion is important.

8.
Sci Rep ; 14(1): 12094, 2024 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802400

RESUMO

Statins are thought to have positive effects on migraine but existing data are inconclusive. We aimed to evaluate the causal effect of such drugs on migraines using Mendelian randomization. We used four types of genetic instruments as proxies for HMG-CoA reductase inhibition. We included the expression quantitative trait loci of the HMG-CoA reductase gene and genetic variation within or near the HMG-CoA reductase gene region. Variants were associated with low-density lipoprotein cholesterol, apolipoprotein B, and total cholesterol. Genome-wide association study summary data for the three lipids were obtained from the UK Biobank. Comparable data for migraine were obtained from the International Headache Genetic Consortium and the FinnGen Consortium. Inverse variance weighting method was used for the primary analysis. Additional analyses included pleiotropic robust methods, colocalization, and meta-analysis. Genetically determined high expression of HMG-CoA reductase was associated with an increased risk of migraines (OR = 1.55, 95% CI 1.30-1.84, P = 6.87 × 10-7). Similarly, three genetically determined HMG-CoA reductase-mediated lipids were associated with an increased risk of migraine. These conclusions were consistent across meta-analyses. We found no evidence of bias caused by pleiotropy or genetic confounding factors. These findings support the hypothesis that statins can be used to treat migraine.


Assuntos
Estudo de Associação Genômica Ampla , Hidroximetilglutaril-CoA Redutases , Inibidores de Hidroximetilglutaril-CoA Redutases , Análise da Randomização Mendeliana , Transtornos de Enxaqueca , Polimorfismo de Nucleotídeo Único , Humanos , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Transtornos de Enxaqueca/genética , Transtornos de Enxaqueca/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Locos de Características Quantitativas , Predisposição Genética para Doença
9.
Cell Stem Cell ; 31(4): 484-498.e5, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38458193

RESUMO

Alginate-encapsulated hepatocyte transplantation is a promising strategy to treat liver failure. However, its clinical application was impeded by the lack of primary human hepatocytes and difficulty in controlling their quality. We previously reported proliferating human hepatocytes (ProliHHs). Here, quality-controlled ProliHHs were produced in mass and engineered as liver organoids to improve their maturity. Encapsulated ProliHHs liver organoids (eLO) were intraperitoneally transplanted to treat liver failure animals. Notably, eLO treatment increased the survival of mice with post-hepatectomy liver failure (PHLF) and ameliorated hyperammonemia and hypoglycemia by providing liver functions. Additionally, eLO treatment protected the gut from PHLF-augmented permeability and normalized the increased serum endotoxin and inflammatory response, which facilitated liver regeneration. The therapeutic effect of eLO was additionally proved in acetaminophen-induced liver failure. Furthermore, we performed assessments of toxicity and biodistribution, demonstrating that eLO had no adverse effects on animals and remained non-tumorigenic.


Assuntos
Falência Hepática Aguda , Falência Hepática , Humanos , Camundongos , Animais , Falência Hepática Aguda/terapia , Falência Hepática Aguda/induzido quimicamente , Distribuição Tecidual , Células Cultivadas , Hepatócitos , Fígado , Falência Hepática/terapia , Falência Hepática/metabolismo , Organoides/metabolismo
10.
Nat Genet ; 56(5): 938-952, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38627596

RESUMO

Cholestatic liver injuries, characterized by regional damage around the bile ductular region, lack curative therapies and cause considerable mortality. Here we generated a high-definition spatiotemporal atlas of gene expression during cholestatic injury and repair in mice by integrating spatial enhanced resolution omics sequencing and single-cell transcriptomics. Spatiotemporal analyses revealed a key role of cholangiocyte-driven signaling correlating with the periportal damage-repair response. Cholangiocytes express genes related to recruitment and differentiation of lipid-associated macrophages, which generate feedback signals enhancing ductular reaction. Moreover, cholangiocytes express high TGFß in association with the conversion of liver progenitor-like cells into cholangiocytes during injury and the dampened proliferation of periportal hepatocytes during recovery. Notably, Atoh8 restricts hepatocyte proliferation during 3,5-diethoxycarbonyl-1,4-dihydro-collidin damage and is quickly downregulated after injury withdrawal, allowing hepatocytes to respond to growth signals. Our findings lay a keystone for in-depth studies of cellular dynamics and molecular mechanisms of cholestatic injuries, which may further develop into therapies for cholangiopathies.


Assuntos
Colestase , Hepatócitos , Animais , Camundongos , Colestase/genética , Colestase/patologia , Colestase/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Fígado/lesões , Fígado/patologia , Proliferação de Células/genética , Ductos Biliares/metabolismo , Regeneração Hepática/genética , Camundongos Endogâmicos C57BL , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Transdução de Sinais , Masculino , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/genética , Transcriptoma , Modelos Animais de Doenças , Análise Espaço-Temporal
11.
Nat Genet ; 56(5): 953-969, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38627598

RESUMO

The mechanism by which mammalian liver cell responses are coordinated during tissue homeostasis and perturbation is poorly understood, representing a major obstacle in our understanding of many diseases. This knowledge gap is caused by the difficulty involved with studying multiple cell types in different states and locations, particularly when these are transient. We have combined Stereo-seq (spatiotemporal enhanced resolution omics-sequencing) with single-cell transcriptomic profiling of 473,290 cells to generate a high-definition spatiotemporal atlas of mouse liver homeostasis and regeneration at the whole-lobe scale. Our integrative study dissects in detail the molecular gradients controlling liver cell function, systematically defining how gene networks are dynamically modulated through intercellular communication to promote regeneration. Among other important regulators, we identified the transcriptional cofactor TBL1XR1 as a rheostat linking inflammation to Wnt/ß-catenin signaling for facilitating hepatocyte proliferation. Our data and analytical pipelines lay the foundation for future high-definition tissue-scale atlases of organ physiology and malfunction.


Assuntos
Homeostase , Regeneração Hepática , Fígado , Via de Sinalização Wnt , Animais , Regeneração Hepática/genética , Camundongos , Fígado/metabolismo , Via de Sinalização Wnt/genética , Hepatócitos/metabolismo , Hepatócitos/citologia , Proliferação de Células/genética , Análise de Célula Única , Redes Reguladoras de Genes , Perfilação da Expressão Gênica/métodos , Transcriptoma , Camundongos Endogâmicos C57BL , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Masculino
12.
Cell Stem Cell ; 30(5): 617-631.e8, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37059100

RESUMO

Liver resection is the first-line treatment for primary liver cancers, providing the potential for a cure. However, concerns about post-hepatectomy liver failure (PHLF), a leading cause of death following extended liver resection, have restricted the population of eligible patients. Here, we engineered a clinical-grade bioartificial liver (BAL) device employing human-induced hepatocytes (hiHeps) manufactured under GMP conditions. In a porcine PHLF model, the hiHep-BAL treatment showed a remarkable survival benefit. On top of the supportive function, hiHep-BAL treatment restored functions, specifically ammonia detoxification, of the remnant liver and facilitated liver regeneration. Notably, an investigator-initiated study in seven patients with extended liver resection demonstrated that hiHep-BAL treatment was well tolerated and associated with improved liver function and liver regeneration, meeting the primary outcome of safety and feasibility. These encouraging results warrant further testing of hiHep-BAL for PHLF, the success of which would broaden the population of patients eligible for liver resection.


Assuntos
Falência Hepática , Fígado Artificial , Humanos , Animais , Suínos , Hepatócitos , Falência Hepática/cirurgia , Regeneração Hepática
13.
J Phys Chem Lett ; 13(30): 6966-6974, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35877977

RESUMO

Transition path flight times are studied for scattering on two electronic surfaces with a single crossing. These flight times reveal nontrivial quantum effects such as resonance lifetimes and nonclassical passage times and reveal that nonadiabatic effects often increase flight times. The flight times are computed using numerically exact time propagation and compared with results obtained from the Fewest Switches Surface Hopping (FSSH) method. Comparison of the two methods shows that the FSSH method is reliable for transition path times only when the scattering is classically allowed on the relevant adiabatic surfaces. However, where quantum effects such as tunneling and resonances dominate, the FSSH method is not adequate to accurately predict the correct times and transition probabilities. These results highlight limitations in methods which do not account for quantum interference effects, and suggest that measuring flight times is important for obtaining insights from the time-domain into quantum effects in nonadiabatic scattering.

14.
Natl Sci Rev ; 9(6): nwab230, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35795460

RESUMO

Cell plasticity endows differentiated cells with competence to be reprogrammed to other lineages. Although extrinsic factors driving cell-identity conversion have been extensively characterized, it remains elusive which intrinsic epigenetic attributes, including high-order chromatin organization, delineate cell plasticity. By analysing the transcription-factor-induced transdifferentiation from fibroblasts to hepatocytes, we uncovered contiguous compartment-switchable regions (CSRs) as a unique chromatin unit. Specifically, compartment B-to-A CSRs, enriched with hepatic genes, possessed a mosaic status of inactive chromatin and pre-existing and continuous accessibility in fibroblasts. Pre-existing accessibility enhanced the binding of inducible factor Foxa3, which triggered epigenetic activation and chromatin interaction as well as hepatic gene expression. Notably, these changes were restrained within B-to-A CSR boundaries that were defined by CTCF occupancy. Moreover, such chromatin organization and mosaic status were detectable in different cell types and involved in multiple reprogramming processes, suggesting an intrinsic chromatin attribute in understanding cell plasticity.

15.
J Phys Chem Lett ; 12(10): 2496-2501, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33667108

RESUMO

The celebrated Meyer-Miller mapping model has been a useful approach for generating practical trajectory-based nonadiabatic dynamics methods. It is generally assumed that the zero-point-energy (ZPE) parameter is positive. The constraint implied in the conventional Meyer-Miller mapping Hamiltonian for an F-electronic-state system actually requires γ∈(-1/F, ∞) for the ZPE parameter for each electronic degree of freedom. Both negative and positive values are possible for such a parameter. We first establish a rigorous formulation to construct exact mapping models in the Cartesian phase space when the constraint is applied. When nuclear dynamics is approximated by the linearized semiclassical initial value representation, a negative ZPE parameter could lead to reasonably good performance in describing dynamic behaviors in typical spin-boson models for condensed-phase two-state systems, even at challenging zero temperature.

16.
Front Neurol ; 12: 546481, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025545

RESUMO

Posterior reversible encephalopathy syndrome (PRES) is a relatively rare clinical disease, characterized by reversible subcortical vasogenic edema. Here, we present the first reported case of PRES induced by anlotinib, a multi-target tyrosine kinase inhibitor. A 56-year-old female patient with lung adenocarcinoma and bone metastasis experienced hypertension and mental confusion when she received anti-angiogenesis treatment. PRES was diagnosed after magnetic resonance of the patient's brain revealed hyperintensities bilaterally around the cerebellum, pons, fronto-parieto-occipital areas, and corona radiate. Diffusion-weighted imaging showed hyperintensities bilaterally in the parieto-occipital cortical regions. Subsequently, the patient was diagnosed with PRES, and remission was achieved with anti-hypertensive drugs. Six cases of rare adverse effects induced by anlotinib were reviewed in the literature. Since anlotinib has been widely applied as a novel third-line treatment in patients with non-small-cell lung cancer, the association between PRES and anlotinib would benefit neurologists and oncologists in future diagnoses and treatment.

17.
Adv Sci (Weinh) ; 8(19): e2101188, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34382351

RESUMO

Although liver-humanized animals are desirable tools for drug development and expansion of human hepatocytes in large quantities, their development is restricted to mice. In animals larger than mice, a precondition for efficient liver humanization remains preliminary because of different xeno-repopulation kinetics in livers of larger sizes. Since rats are ten times larger than mice and widely used in pharmacological studies, liver-humanized rats are more preferable. Here, Fah-/- Rag2-/- IL2rg-/- (FRG) rats are generated by CRISPR/Cas9, showing accelerated liver failure and lagged liver xeno-repopulation compared to FRG mice. A survival-assured liver injury preconditioning (SALIC) protocol, which consists of retrorsine pretreatment and cycling 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC) administration by defined concentrations and time intervals, is developed to reduce the mortality of FRG rats and induce a regenerative microenvironment for xeno-repopulation. Human hepatocyte repopulation is boosted to 31 ± 4% in rat livers at 7 months after transplantation, equivalent to approximately a 1200-fold expansion. Human liver features of transcriptome and zonation are reproduced in humanized rats. Remarkably, they provide sufficient samples for the pharmacokinetic profiling of human-specific metabolites. This model is thus preferred for pharmacological studies and human hepatocyte production. SALIC may also be informative to hepatocyte transplantation in other large-sized species.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Hepatócitos/metabolismo , Hidrolases/metabolismo , Subunidade gama Comum de Receptores de Interleucina/metabolismo , Fígado/metabolismo , Proteínas Nucleares/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Humanos , Hidrolases/genética , Subunidade gama Comum de Receptores de Interleucina/genética , Proteínas Nucleares/genética , Ratos
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