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1.
Immunity ; 54(5): 931-946.e11, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33838102

RESUMO

Activation of the STAT5 transcription factor downstream of the Interleukin-2 receptor (IL-2R) induces expression of Foxp3, a critical step in the differentiation of regulatory T (Treg) cells. Due to the pleiotropic effects of IL-2R signaling, it is unclear how STAT5 acts directly on the Foxp3 locus to promote its expression. Here, we report that IL-2 - STAT5 signaling converged on an enhancer (CNS0) during Foxp3 induction. CNS0 facilitated the IL-2 dependent CD25+Foxp3- precursor to Treg cell transition in the thymus. Its deficiency resulted in impaired Treg cell generation in neonates, which was partially mitigated with age. While the thymic Treg cell paucity caused by CNS0 deficiency did not result in autoimmunity on its own, it exacerbated autoimmune manifestations caused by disruption of the Aire gene. Thus, CNS0 enhancer activity ensures robust Treg cell differentiation early in postnatal life and cooperatively with other tolerance mechanisms minimizes autoimmunity.


Assuntos
Linhagem da Célula/imunologia , Fatores de Transcrição Forkhead/imunologia , Tolerância Imunológica/imunologia , Interleucina-2/imunologia , Linfócitos T Reguladores/imunologia , Animais , Autoimunidade/imunologia , Diferenciação Celular/imunologia , Elementos Facilitadores Genéticos/imunologia , Feminino , Humanos , Subunidade alfa de Receptor de Interleucina-2/imunologia , Masculino , Camundongos , Receptores de Interleucina-2/imunologia , Fator de Transcrição STAT5/imunologia , Transdução de Sinais/imunologia
2.
Hepatology ; 77(3): 965-981, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35938354

RESUMO

BACKGROUND AND AIMS: Chronic HBV infection is the leading cause of HCC and a serious health problem in China, East Asia, and North African countries. Effective treatment of HBV-related HCC is currently unavailable. This study evaluated the therapeutic potential of T-cell immunoreceptor with Ig and ITIM domains (TIGIT) blockade in HBV-related HCC. APPROACH AND RESULTS: A mouse model of spontaneous HBV-related HCC was generated by replacing wild-type hepatocytes with HBsAg + hepatocytes (namely HBs-HepR mice). The tumors in HBs-HepR mice were inflammation-associated HCC, similar to HBV-related HCC in patients, which was distinguished from other HCC mouse models, such as diethylnitrosamine-induced HCC, TGF-ß-activated kinase 1 knockout-induced HCC, HCC in a stelic animal model, or NASH-induced HCC. HCC in HBs-HepR mice was characterized by an increased number of CD8 + T cells, whereas the production of IL-2, TNF-α, and interferon-gamma (IFN-γ) by intrahepatic CD8 + T cells was decreased. Increased expression of TIGIT on CD8 + T cells was responsible for functional exhaustion. The therapeutic effect of TIGIT blockade was investigated at the early and middle stages of HCC progression in HBs-HepR mice. TIGIT blockade reinvigorated intrahepatic CD8 + T cells with increased TNF-α and IFN-γ production and an increased number of CD8 + T cells in tumors, thereby slowing the development of HCC in HBs-HepR mice. Blocking PD-L1 did not show direct therapeutic effects or synergize with TIGIT blockade. CONCLUSIONS: Blockade of TIGIT alone enhanced the antitumor activity of CD8 + T cells during the progression of HBV-related HCC in a spontaneous HCC mouse model.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Linfócitos T CD8-Positivos , Vírus da Hepatite B , Neoplasias Hepáticas/patologia , Receptor de Morte Celular Programada 1 , Receptores de Antígenos de Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Imunoglobulinas/imunologia
3.
Ren Fail ; 46(1): 2296609, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38178573

RESUMO

This study aimed to investigate the correlation between ultrafiltration rate (UFR) and hemoglobin levels and erythropoietin (EPO) response in patients receiving maintenance hemodialysis (MHD). 225 MHD patients were divided into three groups according to the UFR: < 10 ml/h/kg, 10-13 ml/h/kg, and >13 ml/h/kg. Clinical parameters and prognosis were compared among the groups. Multiple linear correlation and regression analyses were conducted. SPSS 26.0 (IBM, Chicago, IL, USA) was used to analyze all statistics. The UFR < 10 ml/h/kg group was older than the other groups (p < 0.05). The UFR > 13 ml/h/kg group had the highest SpKt/V (p < 0.05), monthly EPO dose/weight (p < 0.001), and EPO resistance index (p < 0.001), as well as the lowest dry weight (p < 0.001), BMI (p < 0.001), hemoglobin (p < 0.001), hematocrit (p < 0.05), and red blood cell count (p < 0.05). Multiple linear regression analysis showed that sex, dry weight, UFR, calcium, phosphorus, albumin, and C-reactive protein levels were associated with hemoglobin levels. Multivariate logistic regression analysis revealed that a higher UFR was associated with lower hemoglobin levels, while male sex and higher levels of calcium and albumin were associated with higher hemoglobin levels. High UFR is associated with more severe anemia and EPO resistance in MHD. This study provides new insights into anemia management in patients undergoing hemodialysis.


Assuntos
Anemia , Eritropoetina , Falência Renal Crônica , Humanos , Masculino , Ultrafiltração , Cálcio , Diálise Renal/efeitos adversos , Eritropoetina/uso terapêutico , Epoetina alfa , Hemoglobinas , Albuminas
4.
Langmuir ; 39(46): 16472-16483, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37944116

RESUMO

The immunomodulatory potential of human mesenchymal stromal cells (hMSCs) can be boosted when exposed to interferon-gamma (IFN-γ). While pretreating hMSCs with IFN-γ is a common practice to enhance their immunomodulatory effects, the challenge lies in maintaining a continuous IFN-γ presence within cellular environments. Therefore, in this research, we investigate the sustainable presence of IFN-γ in the cell culture medium by immobilizing it in water-stable metal-organic frameworks (MOFs) [PCN-333(Fe)]. The immobilized IFN-γ in MOFs was coated on top of multilayers composed of combinations of heparin (HEP) and collagen (COL) that were used as a bioactive surface. Multilayers were created by using a layer-by-layer assembly technique, with the final layer alternating between collagen (COL) and heparin (HEP). We evaluated the viability, differentiation, and immunomodulatory activity of hMSCs cultured on (HEP/COL) coated with immobilized IFN-γ in MOFs after 3 and 6 days of culture. Cell viability, compared to tissue culture plastic, was not affected by immobilized IFN-γ in MOFs when they were coated on (HEP/COL) multilayers. We also verified that the osteogenic and adipogenic differentiation of the hMSCs remained unchanged. The immunomodulatory activity of hMSCs was evaluated by examining the expression of indoleamine 2,3-dioxygenase (IDO) and 11 essential immunomodulatory markers. After 6 days of culture, IDO expression and the expression of 11 immunomodulatory markers were higher in (HEP/COL) coated with immobilized IFN-γ in MOFs. Overall, (HEP/COL) multilayers coated with immobilized IFN-γ in MOFs provide a sustained presentation of cytokines to potentiate the hMSC immunomodulatory activity.


Assuntos
Células-Tronco Mesenquimais , Estruturas Metalorgânicas , Humanos , Heparina , Interferon gama/metabolismo , Células Cultivadas , Colágeno/metabolismo , Terapia de Imunossupressão
5.
Immun Ageing ; 20(1): 14, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934284

RESUMO

The aging lungs are vulnerable to chronic pulmonary diseases; however, the underlying mechanisms are not well understood. In this study, we compared the aging lungs of 20-24-month-old mice with the young of 10-16-week-old mice, and found that aging airway epithelial cells significantly upregulated the expression of uteroglobin-related protein 1 (UGRP1), which was responsible for the higher levels of CCL6 in the aging lungs. Alveolar macrophages (AMs) changed intrinsically with aging, exhibiting a decrease in cell number and altered gene expression. Using terminal differentiation trajectories, a population of MARCO+ AMs with the ability to produce CCL6 was identified in the aging lungs. Upregulated UGRP1was demonstrated to modulate CCL6 production of AMs in the UGRP1-MARCO pair in vivo and in vitro. Furthermore, MARCO+ AMs aggravated bleomycin-induced pulmonary fibrosis in a CCL6-dependent manner in the aged mice, and blocking MARCO or neutralizing CCL6 significantly inhibited pulmonary fibrosis, similar to the depletion of AMs. The age-related upregulation of UGRP1 and MARCO+ AMs, involved in the progression of lung fibrosis, was also observed in human lung tissues. Thus, UGRP1 modulated MARCO+ AMs regarding the age-related lung fibrosis in a CCL6-dependent manner, which is key to establishing optimal targeting for the aging population.

6.
Childs Nerv Syst ; 38(6): 1085-1094, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35394210

RESUMO

PURPOSE: To develop and validate a radiomics signature for progression-free survival (PFS) and radiotherapeutic benefits in pediatric medulloblastoma. MATERIALS AND METHODS: We retrospectively enrolled 253 consecutive children with medulloblastoma from two hospitals. A total of 1294 radiomic features were extracted from the region of tumor on the T1-weighted and contrast-enhanced T1-weighted (CE-T1w) MRI. Radiomic feature selection and machine learning modelling were performed to build radiomics signature for the prediction of PFS on the training set. Moreover, the prognostic performance of the clinical parameters was investigated for PFS. The Concordance index (a value of 0.5 indicates no predictive discrimination, and a value of 1 indicates perfect predictive discrimination) was used to measure and compare the prognostic performance of these models. RESULTS: The radiomics signature for the prediction of the PFS yielded Concordance indices of 0.711, 0.707, and 0.717 on the training and held-out test sets 1 and 2, respectively. The radiomics nomogram integrating the radiomics signature, age, and metastasis performed better than the nomogram incorporating only clinicopathological factors (C-index, 0.723 vs. 0.665 and 0.722 vs. 0.677 on the held-out test sets 1 and 2, respectively), which was also validated by the good calibration and decision curve analysis. Further analysis demonstrated that patients with lower value of radiomics signature were associated with better clinical outcomes after postoperative radiotherapy (p < 0.001). CONCLUSION: The radiomics signature and nomogram performed well for the prediction of PFS and could stratify patients underwent postoperative radiotherapy into the high- and low-risk groups with significantly different clinical outcomes.


Assuntos
Neoplasias Cerebelares , Meduloblastoma , Neoplasias Cerebelares/diagnóstico por imagem , Neoplasias Cerebelares/radioterapia , Criança , Humanos , Meduloblastoma/diagnóstico por imagem , Meduloblastoma/radioterapia , Nomogramas , Intervalo Livre de Progressão , Estudos Retrospectivos
7.
Proc Natl Acad Sci U S A ; 116(35): 17409-17418, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31405974

RESUMO

Increasing evidence demonstrates that IL-17A promotes tumorigenesis, metastasis, and viral infection. Natural killer (NK) cells are critical for defending against tumors and infections. However, the roles and mechanisms of IL-17A in regulating NK cell activity remain elusive. Herein, our study demonstrated that IL-17A constrained NK cell antitumor and antiviral activity by restraining NK cell maturation. It was observed that the development and metastasis of tumors were suppressed in IL-17A-deficient mice in the NK cell-dependent manner. In addition, the antiviral activity of NK cells was also improved in IL-17A-deficient mice. Mechanistically, ablation of IL-17A signaling promoted generation of terminally mature CD27-CD11b+ NK cells, whereas constitutive IL-17A signaling reduced terminally mature NK cells. Parabiosis or mixed bone marrow chimeras from Il17a-/- and wild-type (WT) mice could inhibit excessive generation of terminally mature NK cells induced by IL-17A deficiency. Furthermore, IL-17A desensitized NK cell responses to IL-15 and suppressed IL-15-induced phosphorylation of signal transducer and activator of transcription 5 (STAT5) via up-regulation of SOCS3, leading to down-regulation of Blimp-1. Therefore, IL-17A acts as the checkpoint during NK cell terminal maturation, which highlights potential interventions to defend against tumors and viral infections.


Assuntos
Interleucina-15/metabolismo , Interleucina-17/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Animais , Diferenciação Celular/imunologia , Citotoxicidade Imunológica , Células Matadoras Naturais/citologia , Ativação Linfocitária , Masculino , Melanoma Experimental , Camundongos , Camundongos Knockout , Transdução de Sinais
8.
Phys Chem Chem Phys ; 23(33): 17888-17893, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34378570

RESUMO

Ionic liquids (ILs) are potential green solvents with very broad application prospects. Their toxicity and other biological effects are largely related to their hydrophobic properties. In this work, the effects of two imidazolium-based ILs with either a butyl or a hexyl chain, [C4mim][OAc] or [C6mim][OAc], on the phase behaviours of a representative phospholipid, dipalmitoylphosphatidylcholine (DPPC), were examined using synchrotron small- and wide-angle X-ray scattering and differential scanning calorimetry techniques. A series of samples with a lipid : IL molar ratio ranging from 1 : 0 to 1 : 4/1 : 5 were prepared as aqueous dispersions in the form of multi-lamellar vesicles. The two ILs were found to have distinct effects on the phase behaviours of DPPC. For [C4mim][OAc], its effect is very limited. In contrast, for [C6mim][OAc], it could eliminate the pre-transition of DPPC, markedly affect the main phase transition of the lipid, and insert into the DPPC bilayer at gel state to form an interdigitated gel phase. The findings increased our understanding on the biological effects of imidazolium-based ILs and might shed light on the design of novel IL-based antimicrobials.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Imidazóis/química , Líquidos Iônicos/química , Estrutura Molecular , Transição de Fase
9.
Hepatology ; 69(4): 1735-1750, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30329167

RESUMO

Hepatitis B virus (HBV) is a major risk factor for development of hepatocellular carcinoma (HCC), at least partially due to dysfunctional anti-HBV adaptive immunity; however, the role of innate immune response to HBV in this process is not well understood. In this study, low-dose polyinosinic:polycytidylic acid (poly [I:C]), a natural killer (NK) cell activator (3 µg/g body weight, twice/week for 8 weeks), induced HCC in HBV transgenic (HBs-Tg) mice, with an incidence of 100% after 6 months, while HBs-Tg mice without treatment only had HCC with an incidence of 16.7%. In HBs-Tg mice, poly (I:C) induced liver inflammation with markedly increased infiltrating lymphocytes, along with the concurrently increased apoptosis and proliferation of hepatocytes, leading to the accelerated epithelial-to-mesenchymal transition (EMT) of hepatocytes shown by increased expression of the typical transcriptional factors (Slug, Twist, and mothers against decapentaplegic-interacting protein 1) and phenotypic proteins (vimentin and chemokine [C-X-C motif] receptor 4). The EMT and tumorigenesis in this model depended on the presence of NK cells because depletion of these cells significantly reduced the HCC rate to 28.6%. Further, intrahepatic NK cells highly expressed interferon-gamma (IFN-γ), anti-IFN-γ neutralizing monoclonal antibody might obviously alleviate the hepatitis, and hepatocyte-specific IFN-γ overexpression promoted HCC. Moreover, IFN-γ deficiency in HBs-Tg mice prevented HCC occurring, though hepatic NK cells existed and could be activated, suggesting the critical role of IFN-γ in NK cell-mediated tumorigenesis. In an in vitro experiment, IFN-γ up-regulated epithelial cell adhesion molecule (EpCAM) expression through phosphorylated signal transducer and activator of transcription (p-STAT1) pathway, which was followed by EMT, and p-STAT1 inhibitor might absolutely abolish the expression of EpCAM and EMT in HBV surface antigen-positive hepatocytes. Conclusion: This work demonstrates that NK cell-derived IFN-γ promotes HCC through the EpCAM-EMT axis in HBs-Tg mice, revealing the importance of innate immunity in pathogenesis of HBV-associated HCC.


Assuntos
Carcinoma Hepatocelular/etiologia , Transição Epitelial-Mesenquimal , Interferon gama/metabolismo , Células Matadoras Naturais/metabolismo , Neoplasias Hepáticas Experimentais/etiologia , Animais , Molécula de Adesão da Célula Epitelial/metabolismo , Hepatite B/complicações , Hepatite B/imunologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Poli I-C , Fator de Transcrição STAT1/metabolismo
10.
Hepatology ; 70(5): 1804-1815, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31077406

RESUMO

Liver-resident natural killer (LrNK) cells are a unique subset of NK cells that are distinct from conventional NK cells. However, little is known about the mechanisms by which LrNK cells mature. In this study, we discovered that LrNK cells exhibit a relatively immature phenotype and impaired cytotoxic capacity in the absence of CD8+ T cells. The provision of CD8+ T cells to Cd8-/- or Rag1-/- mice led to the restoration of LrNK cell maturation. Furthermore, co-culture with CD8+ T cells induced immature CD27+ LrNK cells to convert into mature CD27- LrNK cells, whereas blocking the interaction of CD70 and CD27 abrogated the ability of CD8+ T cells to promote the maturation of LrNK cells. Conclusion: Our findings indicate that CD8+ T cells promote the maturation of LrNK cells through the CD70-CD27 axis, and therefore highlight a previously unknown mechanism responsible for the mediation of LrNK cell maturation.


Assuntos
Ligante CD27/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Células Matadoras Naturais/fisiologia , Fígado/citologia , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL
11.
Opt Lett ; 45(4): 815-818, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058477

RESUMO

An all-optical tunable whispering gallery mode (WGM) lasing from the liquid-filled hollow glass microsphere (LFHGM) is proposed and experimentally verified. The LFHGM-based microlaser is prepared by injecting ${{\rm NaNdF}_4}/{\rm dye}$NaNdF4/dye co-doped liquid into the HGM, and WGM resonance is obtained under excitation of a 532 nm pulse laser. Since the high-efficiency absorption of the 793 nm continuous-wave laser by ${{\rm NaNdF}_4}$NaNdF4 nanocrystals (NCs) can result in photothermal effect-induced effective refractive index change of the microcavity, a secondary 793 nm laser is irradiated into the LFHGM to excite the ${{\rm NaNdF}_4}$NaNdF4 dispersed in the liquid core, thereby realizing a shift of resonant frequencies. The influence of the doping concentration of ${{\rm NaNdF}_4}$NaNdF4 NCs on the tuning range and the sensitivity over the power intensity range of $0{-}1.{68}\;{{\rm W/mm}^2}$0-1.68W/mm2 are investigated experimentally, obtaining maximum values of 4.95 and ${2}.{95}\;{\rm nm/}({\rm W}\;{{\rm mm}^{ - 2}})$2.95nm/(Wmm-2). The ability to generate stable lasing in a LFHGM cavity highlights the practical application of the microscale lasers in future all-optical networks.

12.
Opt Express ; 27(22): 31629-31643, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684393

RESUMO

Neutral atoms have been observed to survive intense laser pulses in high Rydberg states with surprisingly large probability. Only with this Rydberg-state excitation (RSE) included is the picture of intense-laser-atom interaction complete. Various mechanisms have been proposed to explain the underlying physics. However, neither one can explain all the features observed in experiments and in time-dependent Schrödinger equation (TDSE) simulations. Here we propose a fully quantum-mechanical model based on the strong-field approximation (SFA). It well reproduces the intensity dependence of RSE obtained by the TDSE, which exhibits a series of modulated peaks. They are due to recapture of the liberated electron and the fact that the pertinent probability strongly depends on the position and the parity of the Rydberg state. We also present measurements of RSE in xenon at 800 nm, which display the peak structure consistent with the calculations.

13.
Childs Nerv Syst ; 35(5): 795-800, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30726524

RESUMO

PURPOSE: To establish some explicit, feasible, and reproducible predictors for CMS. MATERIALS AND METHODS: This study was a retrospective case study. Data were obtained from 82 patients with medulloblastoma at a single center, Beijing Tiantan Hospital. Based on medical records, we created two independent samples: the CMS group comprising 23 patients and the non-CMS group comprising 23 patients. Pre-operative imaging was studied by performing quantitative assessments of specific indicators. RESULTS: The CMS group showed greater differences in pre-operative imaging data with the non-CMS group. The Aaxi/daxi ratio in pre-operative MR imaging captured in the axial plane was used to quantify the compression of the cerebellum and brainstem, and significant differences were observed between the CMS group and non-CMS group (p = 0.0002). In the sagittal plane, Dsag*dsag was used to quantify the area of the tumor that invaded the brainstem, and significant differences were observed between the two groups (p = 0.0003). In the coronal plane, Acor/dcor was used to quantify the compression of the upper functional brain region, and significant differences were noted between the two groups (p = 0.0219). Additionally, Evans' index was introduced to quantify the degree of hydrocephalus. The CMS group tended to show an increased Evans' index (p = 0.0027). CONCLUSION: Based on pre-operative imaging data, some reproducible predictors, such as Aaxi/daxi, Dsag*dsag, Acor/dcor, and Evans' index, were established.


Assuntos
Doenças Cerebelares/diagnóstico por imagem , Neoplasias Cerebelares/diagnóstico por imagem , Meduloblastoma/diagnóstico por imagem , Mutismo/diagnóstico por imagem , Cuidados Pré-Operatórios/normas , Doenças Cerebelares/etiologia , Neoplasias Cerebelares/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Meduloblastoma/cirurgia , Mutismo/etiologia , Valor Preditivo dos Testes , Cuidados Pré-Operatórios/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos
14.
Opt Express ; 26(24): 32225-32236, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30650686

RESUMO

We introduce an ab initio approach and the modified strong-field approximation to investigate the alignment-dependent ionization of H2+(1πu) exposed to different few-cycle laser fields. The ab initio calculations are performed by the B-splines one-center method and the Crank-Nicolson method in spherical coordinates. It is shown that the peak ionization probabilities appear around alignment angles 50° and 40° at the laser intensities 3×1013 W/cm2 and 5×1013 W/cm2, respectively, and the above distinct features come from the resonant excitation of the molecular ion, which is confirmed by calculation including and excluding the state 2σg in the basis expansion. Furthermore, the results obtained by including the state 2σg in the ab initio simulations can be qualitatively reproduced by the modified molecular length gauge strong-field approximation (SFA) taking account of the 1πu and 2σg states simultaneously. Analysis indicates that a part of electron is directly emitted from the 1πu orbital and another portion of electron is released from 2σg orbital and other excited state after the single-photon resonant transition between 1πu and 2σg orbitals.

15.
Opt Express ; 25(19): 23082-23092, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-29041612

RESUMO

Using solution of the full three-dimensional time-dependent Schrödinger equation (TDSE) in prolate spheroidal coordinates, we investigate the orientation dependence of ionization of H2+ in near-infrared laser fields. It is found that, the ionization probability decreases as a function of the alignment angle in tunneling ionization regime, while it ascends with the increase of orientation angle in multiphoton ionization regime for the internuclear distance R=2 a.u. Furthermore, the result obtained by the length gauge strong-field approximation theory is in qualitative agreement with that calculated by the TDSE but the radiation gauge strong-field approximation and molecular ADK theories fail to reproduce the TDSE result. Analysis indicates that the above intriguing feature can be ascribed to the interference between the partial electron wave packets emitted from different molecular cores, which becomes evident at low laser intensity due to increased width of the initial mechanical momentum of the photoelectron at ionization moment. In addition, when the internuclear distance increases to R=4 a.u., the ionization yields decrease vs alignment angle in both tunneling and multiphoton regimes since the electron wavefunction of the 1σg orbit is more concentrated in the molecular axis than that of R=2 a.u.

16.
Phys Rev Lett ; 119(24): 243203, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29286720

RESUMO

In this Letter, we propose a novel laser-induced inelastic diffraction (LIID) scheme based on the intense-field-driven atomic nonsequential double ionization (NSDI) process and demonstrate that, with this LIID approach, the doubly differential cross sections (DDCSs) of the target ions, e.g., Ar^{+} and Xe^{+}, can be accurately extracted from the two-dimensional photoelectron momentum distributions in the NSDI process of the corresponding atoms. The extracted DDCSs exhibit a strong dependence on both the target and the laser intensity, in good agreement with calculated DDCSs from the scattering of free electrons. The LIID scheme may be extended to molecular systems and provides a promising approach for imaging of the gas-phase molecular dynamics induced by a strong laser field with unprecedented spatial and temporal resolution.

17.
Opt Express ; 24(22): 25250-25257, 2016 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-27828463

RESUMO

We make a quantitative investigation on the tunneling and multi-photon channels in the transition regime from Keldysh parameter γ < 1 to γ > 1 by numerically solving the time-dependent Schrödinger equation (TDSE). A method is proposed to separate the contributions of those ionization channels based on the characteristics of the current. By analysing the dependence of the ionization rate on the Keldysh parameter γ, we identify a field independent transition point at γ ≈ 2, which is different from the well-accepted consensus of γ ≈ 1, from adiabatic to nonadiabatic regime.

18.
Phys Rev Lett ; 112(7): 073002, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24579593

RESUMO

So far, nonsequential double ionization (NSDI) of atoms can be well understood within a semiclassical or even classical picture. No quantum effect appears to be required to explain the data observed. We theoretically study electron correlation resulting from NSDI of argon in a low-intensity laser field using a quantum-mechanical S-matrix theory. We show that quantum interference between the contributions of different intermediate excited states of the singly charged argon ion produces a transition from back-to-back to side-by-side emission with increasing laser intensity, which is in close agreement with the experimental data. For higher intensities, this transition is enhanced by the consequences of depletion of the excited states.

19.
Viruses ; 16(5)2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38793619

RESUMO

BACKGROUND AND AIMS: The outcomes of HBV infections are related to complex immune imbalances; however, the precise mechanisms by which HBV induces immune dysfunction are not well understood. METHODS: HBV transgenic (HBs-Tg) mice were used to investigate intrahepatic NK cells in two distinct subsets: conventional NK (cNK) and liver-resident NK (LrNK) cells during a chronic HBV infection. RESULTS: The cNK cells, but not the LrNK cells, were primarily responsible for the increase in the number of bulk NK cells in the livers of ageing HBs-Tg mice. The hepatic cNK cells showed a stronger ability to produce IL-10, coupled with a higher expression of CD69, TIGIT and PD-L1, and lower NKG2D expression in ageing HBs-Tg mice. A lower mitochondrial mass and membrane potential, and less polarized localization were observed in the hepatic cNK cells compared with the splenic cNK cells in the HBs-Tg mice. The enhanced galectin-3 (Gal-3) secreted from HBsAg+ hepatocytes accounted for the IL-10 production of hepatic cNK cells via ITGB1 signaling. For humans, LGALS3 and ITGB1 expression is positively correlated with IL-10 expression, and negatively correlated with the poor clinical progression of HCC. CONCLUSIONS: Gal-3-ITGB1 signaling shapes hepatic cNK cells but not LrNK cells during a chronic HBV infection, which may correlate with HCC progression.


Assuntos
Carcinoma Hepatocelular , Galectina 3 , Vírus da Hepatite B , Interleucina-10 , Células Matadoras Naturais , Neoplasias Hepáticas , Fígado , Camundongos Transgênicos , Transdução de Sinais , Animais , Camundongos , Células Matadoras Naturais/imunologia , Humanos , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Interleucina-10/genética , Interleucina-10/metabolismo , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/virologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/virologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fígado/patologia , Fígado/imunologia , Fígado/virologia , Fígado/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Progressão da Doença , Masculino , Feminino , Hepatócitos/virologia , Hepatócitos/metabolismo , Hepatócitos/imunologia , Camundongos Endogâmicos C57BL , Galectinas/genética , Galectinas/metabolismo
20.
Obes Rev ; 25(1): e13646, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37813400

RESUMO

The present systematic review and meta-analysis aimed to summarize the associations between gut microbiota composition and non-alcoholic fatty liver disease. To compare the differences between individuals with or without NAFLD, the standardized mean difference and 95% confidence interval were computed for each α-diversity index and relative abundance of gut microbes. The ß-diversity indices were summarized in a qualitative manner. A total of 54 studies with 8894 participants were included. Overall, patients with NAFLD had moderate reduction in α-diversity indices including Shannon (SMD = -0.36, 95% CI = [-0.53, -0.19], p < 0.001) and Chao 1 (SMD = -0.42, 95% CI = [-0.68, -0.17], p = 0.001), but no significant differences were found for Simpson, observed species, phylogenetic diversity, richness, abundance-based coverage estimator, and evenness (p ranged from 0.081 to 0.953). Over 75% of the included studies reported significant differences in ß-diversity. Although there was substantial interstudy heterogeneity, especially for analyses at the phylum, class, and family levels, the majority of the included studies showed alterations in the depletion of anti-inflammatory microbes (i.e., Ruminococcaceae and Coprococcus) and the enrichment of proinflammatory microbes (i.e., Fusobacterium and Escherichia) in patients with NAFLD. Perturbations in gut microbiota were associated with NAFLD, commonly reflected by a reduction in beneficial species and an increase in the pathogenic species.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Humanos , Filogenia
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