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2.
J Med Virol ; 96(3): e29515, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38469923

RESUMO

Hepatitis B virus (HBV) infection significantly impacts Asian populations. The influences of continuous HBV antigen and inflammatory stimulation to T cells in chronic hepatitis B (CHB) remain unclear. In this study, we first conducted bioinformatics analysis to assess T-cell signaling pathways in CHB patients. In a Taiwanese cohort, we examined the phenotypic features of HBVcore -specific T cells and their correlation with clinical parameters. We used core protein overlapping peptides from the Taiwan prevalent genotype B HBV to investigate the antiviral response and the functional implication of HBV-specific T cells. In line with Taiwanese dominant HLA-alleles, we also evaluated ex vivo HBVcore -specific T cells by pMHC-tetramers targeting epitopes within HBV core protein. Compared to healthy subjects, we disclosed CD8 T cells from CHB patients had higher activation marker CD38 levels but showed an upregulation in the inhibitory receptor PD-1. Our parallel study showed HBV-specific CD8 T cells were more activated with greater PD-1 expression than CMV-specific subset and bulk CD8 T cells. Moreover, our longitudinal study demonstrated a correlation between the PD-1 fluctuation pattern of HBVcore -specific CD8 T cells and liver inflammation in CHB patients. Our research reveals the HBV core antigen-mediated immunopathologic profile of CD8 T cells in chronic HBV infection. Our findings suggest the PD-1 levels of HBVcore -specific CD8 T cells can be used as a valuable indicator of personal immune response for clinical application in hepatitis management.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Vírus da Hepatite B/genética , Receptor de Morte Celular Programada 1/genética , Estudos Longitudinais , Antígenos do Núcleo do Vírus da Hepatite B , Linfócitos T CD8-Positivos
3.
J Mater Chem B ; 12(5): 1361-1371, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38234194

RESUMO

Implantable electrodes have raised great interest over the last years with the increasing incidence of neurodegenerative disorders. For brain implant devices, some key factors resulting in the formation of glial scars, such as mechanical mismatch and acute injury-induced inflammation, should be considered for material design. Therefore, in this study, a new biocompatible flexible electrode (e-SgG) with arbitrary shapes on a positive electrode was developed via electrogelation by applying a direct electrical voltage on a silk fibroin/gelatin/reduced graphene oxide composite hydrogel. The implantable flexible e-SgG-2 film with 1.23% rGO content showed high Young's modulus (11-150 MPa), which was sufficient for penetration under dried conditions but subsequently became a biomimetic brain tissue with low Young's modulus (50-3200 kPa) after insertion in the brain. At the same time, an anti-inflammatory drug (DEX) incorporated into the e-SgG-2 film can be electrically stimulated to exhibit two-stage release to overcome tissue inflammation during cyclic voltammetry via degradation by applying an AC field. The results of cell response to the SF/gelatin/rGO/DEX composite film showed that the released DEX could interrupt astrocyte growth to reduce the inflammatory response but showed non-toxicity toward neurons, which demonstrated a great potential for the application of the biocompatible and degradable e-SgG-D electrodes in the improvement of nerve tissue repair.


Assuntos
Gelatina , Seda , Humanos , Eletrodos Implantados , Encéfalo , Inflamação , Anti-Inflamatórios
4.
Cancers (Basel) ; 15(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37345023

RESUMO

BACKGROUND: Approximately 10-40% of hepatocellular carcinoma (HCC) patients have definite vascular invasion at the time of diagnosis. Without curative treatment options, these patients have an abysmal prognosis with a median survival of only a few months following systemic therapy. However, supportive evidence of combining multiple locoregional treatments with systemic therapy is limited. This study compared the outcomes of sorafenib alone versus multimodality therapy with sorafenib, radiotherapy (RT), and transarterial chemoembolization (TACE) in advanced HCC patients with macrovascular invasion (MaVI). METHODS: The process took place over a nine-year period between March 2009 and October 2017, wherein 78 HCC patients with MaVI who underwent either sorafenib therapy alone (n = 49) or combined sorafenib/RT/TACE (n = 29) therapy were chosen for the retrospective study. We compared the overall survival (OS) between the two groups using the Cox regression hazard model and adjusted imbalances using propensity score matching (PSM). RESULTS: At the last follow-up, 76 patients had died, with a median follow-up time of 4.8 months for all patients and 31 months for those who were alive. Patients treated with sorafenib/RT/TACE had superior OS compared to those treated with sorafenib alone, showing a median survival of 9.3 vs. 2.7 months and a one-year survival of 37.1% vs. 6.1% (p < 0.001). In the multivariable analysis, new diagnosis or recurrence of HCC and treatment modalities (sorafenib alone vs. sorafenib/RT/TACE) were independent prognostic factors for OS. Compared to patients treated with sorafenib alone, significantly better OS was further verified using PSM (p < 0.001) in patients who received multiple therapeutic modalities. CONCLUSION: Multimodality therapy with sorafenib/RT/TACE increased OS threefold versus sorafenib therapy alone in HCC patients with MaVI. This study offers promising benefits of combined locoregional and systemic therapy for advanced HCC in current patient management and prospective clinical trials.

5.
ACS Biomater Sci Eng ; 8(11): 4807-4818, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36222713

RESUMO

Multimodal neural interfaces include combined functions of electrical neuromodulation and synchronic monitoring of neurochemical and physiological signals in one device. The remarkable biocompatibility and electrochemical performance of polystyrene sulfonate-doped poly(3,4-ethylenedioxythiophene) (PEDOT:PSS) have made it the most recommended conductive polymer neural electrode material. However, PEDOT:PSS formed by electrochemical deposition, called PEDOT/PSS, often need multiple doping to improve structural instability in moisture, resolve the difficulties of functionalization, and overcome the poor cellular affinity. In this work, inspired by the catechol-derived adhesion and semiconductive properties of polydopamine melanin (PDAM), we used electrochemical oxidation polymerization to develop PDAM-doped PEDOT (PEDOT/PDAM) as a bioactive multimodal neural interface that permits robust electrochemical performance, structural stability, analyte-trapping capacity, and neural stem cell affinity. The use of potentiodynamic scans resolved the problem of copolymerizing 3,4-ethylenedioxythiophene (EDOT) and dopamine (DA), enabling the formation of PEDOT/PDAM self-assembled nanodomains with an ideal doping state associated with remarkable current storage and charge transfer capacity. Owing to the richness of hydrogen bond donors/acceptors provided by the hydroxyl groups of PDAM, PEDOT/PDAM presented better electrochemical and mechanical stability than PEDOT/PSS. It has also enabled high sensitivity and selectivity in the electrochemical detection of DA. Different from PEDOT/PSS, which inhibited the survival of human induced pluripotent stem cell-derived neural progenitor cells, PEDOT/PDAM maintained cell proliferation and even promoted cell differentiation into neuronal networks. Finally, PEDOT/PDAM was modified on a commercialized microelectrode array system, which resulted in the reduction of impedance by more than one order of magnitude; this significantly improved the resolution and reduced the noise of neuronal signal recording. With these advantages, PEDOT/PDAM is anticipated to be an efficient bioactive multimodal neural electrode material with potential application to brain-machine interfaces.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Melaninas , Polímeros/farmacologia , Neurônios/fisiologia
6.
ACS Appl Mater Interfaces ; 14(41): 46188-46200, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36198117

RESUMO

Although numerous strategies have been implemented to develop nerve guidance conduits (NGCs) to treat peripheral nerve injury (PNI), functionalization of an NGC to make it remotely controllable for providing spatiotemporal modulation on in situ nerve tissues remains a challenge. In this study, a gelatin/silk (GS) hydrogel was used to develop an NGC based on its self-owned reversible thermoresponsive sol-to-gel phase transformation ability that permitted rapid three-dimensional (3D) micropatterning of the incorporated nerve growth factor (NGF)-loaded magnetic poly(lactic-co-glycolic acid) (PLGA) microcapsules (called NGF@MPs) via multiple magnetic guidance. The thermally controllable viscosity of GS enabled the rapid formation of a 3D gradient and linearly aligned distribution of NGF@MPs, leading to magnetically controlled 3D gradient release of NGF to enhance topographical nerve guidance and wound healing in PNIs. Particularly, the as-formed micropatterned hydrogel, called NGF@MPs-GS, showed corrugation topography with a pattern height H of 15 µm, which resulted in the linear axon alignment of more than 90% of cells. In addition, by an external magnetic field, spatiotemporal controllability of NGF release was obtained and permitted neurite elongation that was almost 2-fold longer than that in the group with external addition of NGF. Finally, an NGC prototype was fabricated and implanted into the injured sciatic nerve. The patterned implant, assisted by magnetic stimulation, demonstrated accelerated restoration of motor function within 14 days after implantation. It further contributed to the enhancement of axon outgrowth and remyelination after 28 days. This NGC, with controllable mechanical, biochemical, and topographical cues, is a promising platform for the enhancement of nerve regeneration.


Assuntos
Gelatina , Fator de Crescimento Neural , Fator de Crescimento Neural/farmacologia , Fator de Crescimento Neural/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Cápsulas , Preparações de Ação Retardada/farmacologia , Nervo Isquiático/lesões , Regeneração Nervosa , Hidrogéis/farmacologia , Seda , Fenômenos Magnéticos
7.
Materials (Basel) ; 15(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35744357

RESUMO

The use of scaled-down micro-bumps in miniaturized consumer electronic products has led to the easy realization of full intermetallic solder bumps owing to the completion of the wetting layer. However, the direct contact of the intermetallic compounds (IMCs) with the adhesion layer may pose serious reliability concerns. In this study, the terminal reaction of the Ti adhesion layer with Cu-Sn IMCs was investigated by aging the micro-bumps at 200 °C. Although all of the micro-bumps transformed into intermetallic structures after aging, they exhibited a strong attachment to the Ti adhesion layer, which differs significantly from the Cr system where spalling of IMCs occurred during the solid-state reaction. Moreover, the difference in the diffusion rates between Cu and Sn might have induced void formation during aging. These voids progressed to the center of the bump through the depleting Cu layer. However, they neither affected the attachment between the IMCs and the adhesion layer nor reduced the strength of the bumps. In conclusion, the IMCs demonstrated better adhesive behavior with the Ti adhesion layer when compared to Cr, which has been used in previous studies.

8.
Front Oncol ; 12: 793318, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692778

RESUMO

Aim: Approximately 66% of head and neck cancers are diagnosed at an advanced stage. This prospective study aimed to detect newly diagnosed head and neck cancers using regular upper gastrointestinal (UGI) endoscopy with oral-pharynx-larynx examination. Methods: A total of 2,849 patients underwent UGI endoscopy with an additional oral-pharynx-larynx examination. Patients aged < 20 years, those who were pregnant, had a history of head and neck cancers, were undergoing emergency endoscopy, and had a poor laryngopharyngeal view were excluded. The symptoms, incidence, location, pathology, and stage of malignant neoplasms were investigated. Results: A total of 2,720 patients were enrolled. Endoscopically observable 23 abnormal findings (0.85%) included 18 (0.66%) benign lesions and 5 (0.18%) newly diagnosed malignant neoplasms. Notably, 4 (80%) of 5 patients with malignant neoplasms were diagnosed at an early stage (Stage 0, I, and II). Conclusions: UGI endoscopy with oral-pharynx-larynx examination can achieve opportunistic head neck cancer screening and is recommended for every patient in endoscopy units.

10.
Materials (Basel) ; 15(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35207937

RESUMO

Sintered silver paste is widely used as the die-attachment material for power semiconductors. However, sintered silver joints encounter problems, such as severe coarsening of sintered pores and oxidation issues, in harsh high-temperature environments. These lead to the deterioration of the die-attachment joints. In this paper, a novel method of sintering silver joints is demonstrated, where silver-indium alloy paste is used to improve the reliability of sintered Ag joints. The silver-indium (Ag-In) alloy paste was fabricated through mechanical alloying using the ball-milling technique. The well-bonded sintered Ag-In alloy joints inhibited pore coarsening better than pure sintered Ag joints and significantly enhanced the mechanical properties at high operating temperatures. Lastly, an oxidation mechanism for the sintered joint was proposed, and strategies to prevent such high-temperature oxidation were discussed.

11.
ACS Nano ; 16(3): 4014-4027, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35225594

RESUMO

T lymphocyte infiltration with immunotherapy potentially suppresses most devastating brain tumors. However, local immune privilege and tumor heterogeneity usually limit the penetration of immune cells and therapeutic agents into brain tumors, leading to tumor recurrence after treatment. Here, a rabies virus glycoprotein (RVG)-camouflaged gold yarnball (RVG@GY) that can boost the targeting efficiency at a brain tumor via dual hierarchy- and RVG-mediated spinal cord transportation, facilitating the decrease of tumor heterogeneity for T cell infiltration, is developed. Upon magnetoelectric irradiation, the electron current generated on the GYs activates the electrolytic penetration of palbociclib-loaded dendrimer (Den[Pb]) deep into tumors. In addition, the high-density GYs at brain tumors also induces the disruption of cell-cell interactions and T cell infiltration. The integration of the electrolytic effects and T cell infiltration promoted by drug-loaded RVG@GYs deep in the brain tumor elicits sufficient T cell numbers and effectively prolongs the survival rate of mice with orthotopic brain tumors.


Assuntos
Neoplasias Encefálicas , Vírus da Raiva , Animais , Neoplasias Encefálicas/tratamento farmacológico , Glicoproteínas , Ouro/uso terapêutico , Camundongos , Linfócitos T/patologia
12.
Micromachines (Basel) ; 12(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34577700

RESUMO

Hydrogels are the ideal materials in the development of implanted bioactive neural interfaces because of the nerve tissue-mimicked physical and biological properties that can enhance neural interfacing compatibility. However, the integration of hydrogels and rigid/dehydrated electronic microstructure is challenging due to the non-reliable interfacial bonding, whereas hydrogels are not compatible with most conditions required for the micromachined fabrication process. Herein, we propose a new enzyme-mediated transfer printing process to design an adhesive biological hydrogel neural interface. The donor substrate was fabricated via photo-crosslinking of gelatin methacryloyl (GelMA) containing various conductive nanoparticles (NPs), including Ag nanowires (NWs), Pt NWs, and PEDOT:PSS, to form a stretchable conductive bioelectrode, called NP-doped GelMA. On the other hand, a receiver substrate composed of microbial transglutaminase-incorporated gelatin (mTG-Gln) enabled simultaneous temporally controlled gelation and covalent bond-enhanced adhesion to achieve one-step transfer printing of the prefabricated NP-doped GelMA features. The integrated hydrogel microelectrode arrays (MEA) were adhesive, and mechanically/structurally bio-compliant with stable conductivity. The devices were structurally stable in moisture to support the growth of neuronal cells. Despite that the introduction of AgNW and PEDOT:PSS NPs in the hydrogels needed further study to avoid cell toxicity, the PtNW-doped GelMA exhibited a comparable live cell density. This Gln-based MEA is expected to be the next-generation bioactive neural interface.

13.
Biomaterials ; 271: 120762, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33773400

RESUMO

Although traditional 3D scaffolds or biomimetic hydrogels have been used for tissue engineering and regenerative medicine, soft tissue microenvironment usually has a highly anisotropic structure and a dynamically controllable deformation with various biomolecule distribution. In this study, we developed a hierarchical hybrid gelatin methacrylate-microcapsule hydrogel (HGMH) with Neurotrophin-3(NT-3)-loaded PLGA microcapsules to fabricate anisotropic structure with patterned NT-3 distribution (demonstrated as striped and triangular patterns) by dielectrophoresis (DEP). The HGMH provides a dynamic biomimetic sinuate-microwrinkles change with NT-3 spatial gradient and 2-stage time-dependent distribution, which was further simulated using a 3D finite element model. As demonstrated, in comparison with striped-patterned hydrogel, the triangular-patterned HGMH with highly anisotropic array of microcapsules exhibits remarkably spatial NT-3 gradient distributions that can not only guide neural stem cells (NSCs) migration but also facilitate spinal cord injury regeneration. This approach to construct hierarchical 4D hydrogel system via an electromicrofluidic platform demonstrates the potential for building various biomimetic soft scaffolds in vitro tailed to real soft tissues.


Assuntos
Hidrogéis , Regeneração da Medula Espinal , Cápsulas , Engenharia Tecidual , Tecidos Suporte
14.
Nanoscale ; 12(46): 23532-23536, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33237060

RESUMO

In this paper, the instability mechanism of resistive random access memory (RRAM) was investigated, and a technique was developed to stabilize the distribution of high resistance states (HRS) and better concentrate the set voltage. Due to the accumulation of oxygen, an interface-type switching characteristic was observed on the I-V curves beneath the filament-type switching behavior. In this work, the interface-type switching characteristic is used to fit the natural distribution of HRS as an analysis of the instability mechanism. According to the results, the HRS distribution is attributed to the accumulation of excess oxygen ions left from the lower oxygen content and oxygen vacancy recombination during the reset process. The proposed solution with simple plasma treatment, can create an excess oxygen reservoir by changing the surface topography of the electrode to store the surplus oxygen ions from the reset process, eliminating the oxygen accumulation effect and further improving the device stability.

15.
Neuropsychiatr Dis Treat ; 16: 1717-1726, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764947

RESUMO

PURPOSE: Previous suicide behavior predicts future suicide risk. Studies of suicide repetition are important for suicide prevention. This study examined the clinical characteristics and psychiatric comorbidities of pesticide self-harm as associated with suicide attempt repetition status. PATIENTS AND METHODS: This retrospective, observational study included patients admitted to a medical center in northern Taiwan between 2000 and 2015 following suicide attempts by pesticide. Diagnoses were made by a consultation-liaison psychiatry team based on the DSM IV-TR criteria. Independent samples t-test was used to analyze the quantitative variables and Pearson's Chi-squared test with a Bonferroni adjustment for categorical variables. Univariate binary logistic regression analysis was conducted to determine the predictors for repeated suicide attempt and multivariate binary logistic regression analysis to identify significant associated factors. RESULTS: Among 151 patients, organophosphate pesticides were the most used (80.8%). The average age was 52.9±17.2 years. Most patients were married males from rural areas, with depressive disorder most often diagnosed (40.4%). Nearly one-third of them were suicide repeaters (n=43, 28.5%); these patients were less likely to be married (53.5%, p=0.001), had previously used psychiatric services (72.1%, p<0.001) and chose complex suicide (46.5%, p=0.014) more often compared to nonrepeaters. No significant differences were found between repeaters and nonrepeaters regarding psychiatric comorbidities. Multivariate logistic regression analysis revealed that marital status (odds ratio: 2.916, 95% confidence interval: 1.234-6.891, p=0.015) and previous psychiatric services usage (odds ratio: 6.897, 95% confidence interval: 3.012-15.625, p<0.001) were significant risk factors associated with suicide repetition. CONCLUSION: Pesticide suicide repeaters were characterized by less likely to be married and more likely to use psychiatric services before suicide attempts. These features help ensuring that the needs of people who have made a suicide attempt are addressed, and it reduces the likelihood of repetition.

16.
ACS Biomater Sci Eng ; 6(2): 1144-1153, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33464846

RESUMO

Effective integration of stimulation and direction in bionic scaffolds by materials and microstructure design has been the focus in the advancement of nerve regeneration. Hydrogels are the most promising biomimicked materials used in developing nerve grafts, but the highly hydrated networks limit the fabrication of hydrogel materials into complex biomedical devices. Herein, facile lithography-free and spontaneously micropatterned techniques were used to fabricate a smart protein hydrogel-based scaffold, which carried topographical, electrical, and chemical induction for neural regulation. The synthesized tissue-mimicked silk-gelatin (SG)/polylactic acid bilayer system can self-form three-dimensional ordered corrugation micropatterns with well-defined dimensions (wavelength, λ) based on the stress-induced topography. Through magnetically and topographically guided deposition of the synthesized nerve growth factor-incorporated Fe3O4-graphene nanoparticles (GFPNs), a biologically and electrically conductive cell passage with one-dimensional directionality was constructed to allow for a controllable constrained geometric effect on neuronal adhesion, differentiation, and neurite orientation. Particularly, the SG with corrugation patterns of λ ≈ 30 µm resulted in the optimal cell adhesion and differentiation in response to the pattern guidance. Furthermore, the additional electrical stimulation applied on GFPN-deposited SG resulted in a 1.5-fold increase in the neurite elongation by day 7, finally leading to the neuronal connection by day 21. Such a hydrogel device with synergistic effects of physical and chemical enhancement on neuronal activity provides an expectable opportunity in the development of next-generation nerve conduits.


Assuntos
Gelatina , Seda , Condutividade Elétrica , Eletricidade , Hidrogéis
18.
ACS Appl Mater Interfaces ; 11(12): 11270-11282, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30844235

RESUMO

Optogenetics is a recently established neuromodulation technique in which photostimulation is used to manipulate neurons with high temporal and spatial precision. However, sequential genetic and optical insertion with double brain implantation tends to cause excessive tissue damage. In addition, the incorporation of light-sensitive genes requires the utilization of viral vectors, which remains a safety concern. Here, by combining device fabrication design, nanotechnology, and cell targeting technology, we developed a new gene-embedded optoelectrode array for neural implantation to enable spatiotemporal electroporation (EP) for gene delivery/transfection, photomodulation, and synchronous electrical monitoring of neural signals in the brain via one-time implantation. A biotic-abiotic neural interface (called PG) composed of reduced graphene oxide and conductive polyelectrolyte 3,4-ethylenedioxythiophene-modified amphiphilic chitosan was developed to form a nanostructural hydrogel with assembled nanodomains for encapsulating nonviral gene vectors (called PEI-NT-pDNA) formulated by neurotensin (NT) and polyethylenimine (PEI)-coupled plasmid DNA (pDNA). The PG can maintain high charge storage ability to respond to a minimal current of 125 µA for controllable gene delivery. The in vitro analysis of PG-PEI-NT-pDNA on the microelectrode array chip showed that the microelectrodes provided electrically inductive electropermeabilization, which permitted gene transfection into localized rat adrenal pheochromocytoma cells with a strong green fluorescent protein expression that was up to 8-fold higher than that in nontreated cells. Furthermore, the in vivo implantation enabled on-demand spatiotemporal gene transfection to neurons with 10-fold enhancement of targeting ability compared with astrocytes. Finally, using the real optogenetic opsin channelrhodopsin-2, the flexible neural probe incorporated with an optical waveguide fiber displayed photoevoked extracellular spikes in the thalamic ventrobasal region after focal EP for only 7 days, which provided a proof of concept for the use of photomodulation to facilitate neural therapies.


Assuntos
Nanoestruturas/química , Neurônios/fisiologia , Optogenética/métodos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/química , Sobrevivência Celular/efeitos dos fármacos , Condutividade Elétrica , Eletrodos Implantados , Grafite/química , Hidrogéis/química , Microeletrodos , Microscopia de Fluorescência , Neurotensina/química , Células PC12 , Plasmídeos/química , Plasmídeos/metabolismo , Polietilenoimina/química , Polímeros/química , Ratos , Transfecção
19.
Front Immunol ; 9: 1009, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867983

RESUMO

NK cells have potent antitumor capacity. They are enriched in the human liver, with a large subset specialized for tissue-residence. The potential for liver-resident versus liver-infiltrating NK cells to populate, and exert antitumor functions in, human liver tumors has not been studied. We examined liver-resident and liver-infiltrating NK cells directly ex vivo from human hepatocellular carcinomas (HCCs) and liver colorectal (CRC) metastases, compared with matched uninvolved liver tissue. We found that NK cells were highly prevalent in both HCC and liver CRC metastases, although at lower frequencies than unaffected liver. Up to 79% of intratumoral NK cells had the CXCR6+CD69+ liver-resident phenotype. Direct ex vivo staining showed that liver-resident NK cells had increased NKG2D expression compared to their non-resident counterparts, but both subsets had NKG2D downregulation within liver tumors compared to uninvolved liver. Proliferation of intratumoral NK cells (identified by Ki67) was selectively impaired in those with the most marked NKG2D downregulation. Human liver tumor NK cells were functionally impaired, with reduced capacity for cytotoxicity and production of cytokines, even when compared to the hypo-functional tissue-resident NK cells in unaffected liver. Coculture of human liver NK cells with the human hepatoma cell line PLC/PRF/5, or with autologous HCC, recapitulated the defects observed in NK cells extracted from tumors, with downmodulation of NKG2D, cytokine production, and target cell cytotoxicity. Transwells and conditioned media confirmed a requirement for cell contact with PLC/PRF/5 to impose NK cell inhibition. IL-15 was able to recover antitumor functionality in NK cells inhibited by in vitro exposure to HCC cell lines or extracted directly from HCC. In summary, our data suggest that the impaired antitumor function of local NK cells reflects a combination of the tolerogenic features inherent to liver-resident NK cells together with additional contact-dependent inhibition imposed by HCC itself. The demonstration that IL-15 can recover hepatic NK cell function following tumor exposure supports its inclusion in immunotherapy strategies.


Assuntos
Carcinoma Hepatocelular/imunologia , Interleucina-15/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Neoplasias Hepáticas/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Carcinoma Hepatocelular/complicações , Linhagem Celular Tumoral , Movimento Celular , Técnicas de Cocultura , Citocinas/imunologia , Citotoxicidade Imunológica , Regulação para Baixo , Humanos , Imunoterapia , Células Matadoras Naturais/patologia , Neoplasias Hepáticas/terapia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Transdução de Sinais
20.
Nanotechnology ; 29(30): 305701, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-29726843

RESUMO

A graded fullerene derivative thin film was used as a dual-functional electron transport layer (ETL) in CH3NH3PbI3 (MAPbI3) solar cells, to improve the fill factor (FF) and device stability. The graded ETL was made by mixing phenyl-C61-butyric acid methyl ester (PCBM) molecules and C60-diphenylmethanofullerene-oligoether (C60-DPM-OE) molecules using the spin-coating method. The formation of the graded ETLs can be due to the phase separation between hydrophobic PCBM and hydrophilic C60-DPM-OE, which was confirmed by XPS depth-profile analysis and an electron energy-loss spectroscope. Comprehensive studies were carried out to explore the characteristics of the graded ETLs in MAPbI3 solar cells, including the surface properties, electronic energy levels, molecular packing properties and energy transfer dynamics. The elimination of the s-shape in the current density-voltage curves results in an increase in the FF, which originates from the smooth contact between the C60-DPM-OE and hydrophilic MAPbI3 and the formation of the more ordered ETL. There was an improvement in device stability mainly due to the decrease in the photothermal induced morphology change of the graded ETLs fabricated from two fullerene derivatives with distinct hydrophilicity. Consequently, such a graded ETL provides dual-functional capabilities for the realization of stable high-performance MAPbI3 solar cells.

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