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1.
ACS Appl Mater Interfaces ; 16(6): 7470-7479, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38299515

RESUMO

Neuromorphic light sensors with analogue-domain image processing capability hold promise for overcoming the energy efficiency limitations and latency of von Neumann architecture-based vision chips. Recently, metal halide perovskites, with strong light-matter interaction, long carrier diffusion length, and exceptional photoelectric conversion efficiencies, exhibit reconfigurable photoresponsivity due to their intrinsic ion migration effect, which is expected to advance the development of visual sensors. However, suffering from a large bandgap, it is challenging to achieve highly tunable responsivity simultaneously with a wide-spectrum response in perovskites, which will significantly enhance the image recognition accuracy through the machine learning algorithm. Herein, we demonstrate a broadband neuromorphic visual sensor from visible (Vis) to near-infrared (NIR) by coupling all-inorganic metal halide perovskites (CsPbBr3) with narrow-bandgap lead sulfide (PbS). The PbS/CsPbBr3 heterostructure is composed of high-quality single crystals of PbS and CsPbBr3. Interestingly, the ion migration of CsPbBr3 with the implementation of an electric field induces the energy band dynamic bending at the interface of the PbS/CsPbBr3 heterojunction, leading to reversible, multilevel, and linearly tunable photoresponsivity. Furthermore, the reconfigurable and broadband photoresponse in the PbS/CsPbBr3 heterojunction allows convolutional neuronal network processing for pattern recognition and edge enhancements from the Vis to the NIR waveband, suggesting the great potential of the PbS/CsPbBr3 heterostructure in artificial intelligent vision sensing.

2.
J Stroke Cerebrovasc Dis ; 33(1): 107431, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951082

RESUMO

OBJECTIVES: To investigate the 10-year trend in healthcare quality of intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator in acute ischemic stroke (AIS) in China. MATERIALS AND METHODS: We analyzed 42,188 AIS within 7 days of onset from the China National Stroke Registry (CNSR) Ⅰ-Ⅲ. Primary outcomes were temporal changes in the proportion of patients arriving at the hospital within 3.5 hours (and 2 hours) of onset and receiving IVT within 4.5 hours (and 3 hours), stratified by region and hospital tier. Secondary outcomes included temporal changes in door-to-needle time (DNT), DNT ≤60 min and favorable outcome defined as a 90-day modified Rankin Scale (mRS) of 0-1. RESULTS: Among patients arriving at the hospital within 3.5 hours of onset, 13.5%, 7.1% and 33.4% patients received IVT within 4.5 hours in CNSR Ⅰ, Ⅱ and Ⅲ, respectively, including a higher proportion from eastern China (37.0%) and tertiary hospitals (36.5%). The median DNT was shorter in CNSR Ⅲ (60.0 min) than those in Ⅱ (95.0 min) and I (94.0 min). The proportion of patients with DNT ≤60 min was greater in Ⅲ (53.4%) than those in Ⅱ (26.7%) and Ⅰ (13.4%). The proportion of favorable outcomes was higher in CNSR Ⅲ (72.8%) than those in Ⅱ (49.6%) and Ⅰ (49.4%). Similar trends were observed for patients arriving at the hospital within 2 hours and receiving IVT within 3 hours of onset. CONCLUSIONS: The healthcare quality of IVT has improved remarkably in the past decade, notably in eastern China and tertiary hospitals.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Ativador de Plasminogênio Tecidual/efeitos adversos , Fibrinolíticos/efeitos adversos , AVC Isquêmico/tratamento farmacológico , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Tempo para o Tratamento , Resultado do Tratamento , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/tratamento farmacológico , Centros de Atenção Terciária , China , Sistema de Registros
3.
Brain Behav ; 13(7): e3047, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37278139

RESUMO

OBJECTIVES: Executive function in people with depression is linked to the integrity of white matter fibers in the brain. We hypothesized that the maze tests in neuropsychological tests assessed reasoning and problem-solving abilities dependent on the integrity of brain white matter fibers, and assessed this relationship using diffusion tensor imaging (DTI) in depressed patients and healthy controls. METHODS: Participants aged from 18 to 50 years were recruited from Zhumadian Second People's Hospital from July 2018 to August 2019. The sample included 33 clinically diagnosed individuals with major depressive disorder (MDD) and 24 healthy volunteers (HVs). All subjects underwent Neuropsychological assessment battery (NAB) maze tests and DTI. Tract-based spatial statistics technology in FSL software was used to process DTI data, and threshold-free cluster enhancement (TFCE) was used to perform multiple comparison corrections. The fractional anisotropy (FA) of white matter fibers in the MDD group and HVs group were compared and extracted. Pearson correlation was used to analyze the relationship between FA and NAB scores and HAMD scores. RESULTS: The mean NAB maze test score for the MDD group was lower than the HVs group, and the difference was statistically significant (F = 11.265, p = .037). The FA value of the body of corpus callosum and cerebral peduncle right in the depression group was lower than that in the healthy control group, and the difference was statistically significant (p < .05). FA value of the body of corpus callosum was positively correlated with NAB score (r = 0.400, p = .036), but not with the HAMD score (r = 0.065, p = .723). CONCLUSIONS: The decreased ability of reasoning and problem-solving in MDD may be due to the decreased integrity of the white matter fibers of the body of the corpus callosum.


Assuntos
Transtorno Depressivo Maior , Substância Branca , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Imagem de Tensor de Difusão , Encéfalo/diagnóstico por imagem , Corpo Caloso
4.
Heliyon ; 9(1): e12803, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36647358

RESUMO

Building energy demands are influenced by the window-to-wall ratio (WWR). The impact of the WWR on the energy demand in the same area has been researched by software. However, the impact of the WWR on the energy demand of buildings in different locations of China has not been investigated using the energy balance equation. The equation for the indoor temperature variation under various internal and external disturbances was provided in this study. The relationship between parameters A and B and the change in indoor temperature was proven. China's Harbin, Beijing, and Chengdu air-conditioning and heating loads, as well as the impact of changing WWR on the rate of energy savings for air-conditioning and heating energy demand, were studied. After investigating the changes in the cooling and heating loads in various cities under various WWRs, the suitable relationship between the cooling and heating loads and the WWR of three urban units was discovered. The findings indicated that despite the three cities' various climates and the diverse energy demands for air conditioning and heating in each city, with the same change in the WWR of urban buildings, the change rate of the air conditioning and heating loads in each city was near. Meanwhile, the heating and cooling loads were linear with WWR.

5.
PLoS One ; 17(12): e0277076, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36469514

RESUMO

BACKGROUND: It is difficult to make a precise diagnosis to distinguish patients with Major Depressive Disorder (MDD) from patients with Bipolar Depressive Disorder (current depressive episode, BD). This study will explore the difference in time perception between MDD and BD using a temporal bisection task. METHODS: In this temporal bisection task, 30 MDD patients, 30 BD patients, and 30 healthy controls (HC) had to categorize a signal duration, between 400 and 1600 milliseconds (ms), as either short or long. A repeated measurement analysis of variance with 3 (subject type) × 7 (time interval) was performed on the long response ratio with Bonferroni correction for multiple comparisons. Origin software was used to calculate the subjective bisection point (BP), difference limen (DL), and Weber ratio (WR). The Hamilton Depression Rating Scale for depression-17 was used to assess depressive symptoms in the patients. RESULTS: The data showed that the interaction effect between subject type and duration was significant (F (6,498) = 4.656, p <0.001, η2p = 0.101). At 400 ms, and the long response of the MDD group was greater than HC group (p<0.017, Bonferroni-corrected). At 1200, 1400 and 1600 ms, the long response of BD group is smaller than HC group, (p<0.017, Bonferroni-corrected). The one-way ANOVA revealed significant difference among the HC, MDD and BD groups in the BP values WR values, F(2, 81) = 3.462, p = 0.036 vs. F(2, 81) = 3.311, p = 0.042. Post-hoc tests showed that the value of BP in the MDD group was less than BD group (p = 0.027) and the value of BP in the MDD group was less than HC group (p = 0.027), while there was not significant difference of BP values between BD group and HC group. The WR values in MDD group larger than the HC group (p = 0.022). LIMITATIONS: Severity of depression not divided and analyzed according to the Hamilton Depression Rating Scale score. CONCLUSION: The time perception of the MDD and BD groups was different from that of the HC group, they overestimated short time periods. Compared with the BD group, the MDD group had a smaller time bisector, and these patients felt that time passed more slowly. The time sensitivity of MDD group and BD group were less than the HC group. However, there was no statistical difference in time sensitivity between the MDD and BD groups.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Percepção do Tempo , Humanos , Transtorno Bipolar/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Emoções
6.
Mol Cell ; 81(24): 5052-5065.e6, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34847358

RESUMO

Accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) lumen triggers an unfolded protein response (UPR) for stress adaptation, the failure of which induces cell apoptosis and tissue/organ damage. The molecular switches underlying how the UPR selects for stress adaptation over apoptosis remain unknown. Here, we discovered that accumulation of unfolded/misfolded proteins selectively induces N6-adenosine-methyltransferase-14 (METTL14) expression. METTL14 promotes C/EBP-homologous protein (CHOP) mRNA decay through its 3' UTR N6-methyladenosine (m6A) to inhibit its downstream pro-apoptotic target gene expression. UPR induces METTL14 expression by competing against the HRD1-ER-associated degradation (ERAD) machinery to block METTL14 ubiquitination and degradation. Therefore, mice with liver-specific METTL14 deletion are highly susceptible to both acute pharmacological and alpha-1 antitrypsin (AAT) deficiency-induced ER proteotoxic stress and liver injury. Further hepatic CHOP deletion protects METTL14 knockout mice from ER-stress-induced liver damage. Our study reveals a crosstalk between ER stress and mRNA m6A modification pathways, termed the ERm6A pathway, for ER stress adaptation to proteotoxicity.


Assuntos
Adenina/análogos & derivados , Estresse do Retículo Endoplasmático , Degradação Associada com o Retículo Endoplasmático , Retículo Endoplasmático/enzimologia , Hepatopatias/enzimologia , Fígado/enzimologia , Metiltransferases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Adenina/metabolismo , Animais , Apoptose , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/patologia , Células HEK293 , Células Hep G2 , Humanos , Fígado/patologia , Hepatopatias/etiologia , Hepatopatias/genética , Hepatopatias/patologia , Metiltransferases/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Células NIH 3T3 , Proteólise , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/metabolismo , Deficiência de alfa 1-Antitripsina/complicações , Deficiência de alfa 1-Antitripsina/enzimologia , Deficiência de alfa 1-Antitripsina/genética
7.
Front Psychol ; 12: 688376, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630204

RESUMO

Objective: To explore the characteristics of expression recognition and spontaneous activity of the resting state brain in major depressive disorder (MDD) patients to find the neural basis of expression recognition and emotional processing. Methods: In this study, two of the six facial expressions (happiness, sadness, anger, fear, aversion, and surprise) were presented in quick succession using a short expression recognition test. The differences in facial expression recognition between MDD patients and healthy people were compared. Further, the differences in ReHo values between the two groups were compared using a resting-state functional magnetic resonance imaging (fMRI) scan to investigate the characteristics of spontaneous brain activity in the resting state and its relationship with clinical symptoms and the accuracy of facial expression recognition in patients with MDD. Results: (1) The accuracy of facial expression recognition in patients with MDD was lower than that of the HC group. There were differences in facial expression recognition between the two groups in sadness-anger (p = 0.026), surprise-aversion (p = 0.038), surprise-happiness (p = 0.014), surprise-sadness (p = 0.019), fear-happiness (p = 0.027), and fear-anger (p = 0.009). The reaction time for facial expression recognition in the patient group was significantly longer than that of the HC group. (2) Compared with the HC group, the ReHo values decreased in the left parahippocampal gyrus, left thalamus, right putamen, left putamen, and right angular gyrus, and increased in the left superior frontal gyrus, left middle temporal gyrus, left medial superior frontal gyrus, and right medial superior frontal gyrus in the patient group. (3) Spearman correlation analysis showed no statistical correlation between ReHo and HAMD-17 scores in MDD patients (p > 0.05). The ReHo value of the left putamen was negatively correlated with the recognition of fear-surprise (r = -0.429, p = 0.016), the ReHo value of the right angular gyrus was positively correlated with the recognition of sadness-anger (r = 0.367, p = 0.042), and the ReHo value of the right medial superior frontal gyrus was negatively correlated with the recognition of fear-anger (r = -0.377, p = 0.037). Conclusion: In view of the different performance of patients with MDD in facial expression tasks, facial expression recognition may have some suggestive effect on the diagnosis of depression and has clinical guiding significance. Many brain regions, including the frontal lobe, temporal lobe, striatum, hippocampus, and thalamus, in patients with MDD show extensive ReHo abnormalities in the resting state. These brain regions with abnormal spontaneous neural activity are important components of LCSPT and LTC circuits, and their dysfunctional functions cause disorder of emotion regulation. The changes in spontaneous activity in the left putamen, right angular gyrus, and right medial superior frontal gyrus may represent the abnormal pattern of spontaneous brain activity in the neural circuits related to emotion perception and may be the neural basis of facial expression recognition.

10.
FASEB J ; 34(10): 13156-13170, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32860267

RESUMO

The presence of DNA in the cytosol is usually a sign of microbial infections, which alerts the host innate immune system to mount a defense response. Cyclic GMP-AMP synthase (cGAS) is a critical cytosolic DNA sensor that elicits robust innate immune responses through the production of the second messenger, cyclic GMP-AMP (cGAMP), which binds and activates stimulator of interferon genes (STING). However, cGAS binds to DNA irrespective of DNA sequence, therefore, self-DNA leaked from the nucleus or mitochondria can also serve as a cGAS ligand to activate this pathway and trigger extensive inflammatory responses. Dysregulation of the cGAS-STING pathway is responsible for a broad array of inflammatory and autoimmune diseases. Recently, evidence has shown that self-DNA release and cGAS-STING pathway over-activation can drive lung disease, making this pathway a promising therapeutic target for inflammatory lung disease. Here, we review recent advances on the cGAS-STING pathway governing self-DNA sensing, highlighting its role in pulmonary disease.


Assuntos
DNA/metabolismo , Pneumopatias/metabolismo , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , Transdução de Sinais , Animais , Humanos , Pneumopatias/genética , Proteínas de Membrana/genética , Nucleotidiltransferases/genética
11.
Am J Respir Cell Mol Biol ; 63(4): 415-423, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32609537

RESUMO

Respiratory infections from influenza A virus (IAV) cause substantial morbidity and mortality in children relative to adults. T cells play a critical role in the host response to IAV by supporting the innate and humoral responses, mediating cytotoxic activity, and promoting recovery. There are age-dependent differences in the number, subsets, and localization of T cells, which impact the host response to pathogens. In this article, we first review how T cells recognize IAV and examine differences in the resting T-cell populations between juveniles and adults. Next, we describe how the juvenile CD4+, CD8+, and regulatory T-cell responses compare with those in adults and discuss the potential physiologic and clinical consequences of the differences. Finally, we explore the roles of two unconventional T-cell types in the juvenile response to influenza, natural-killer T cells and γδ T cells. A clear understanding of age-dependent differences in the T-cell response is essential to developing therapies to prevent or reverse the deleterious effects of IAV in children.


Assuntos
Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Infecções por Orthomyxoviridae/imunologia , Linfócitos T/imunologia , Fatores Etários , Animais , Humanos , Influenza Humana/virologia , Infecções por Orthomyxoviridae/virologia
12.
Elife ; 92020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32154783

RESUMO

The distribution of complementary metabolic functions in hepatocytes along a portocentral axis is called liver zonation. Endothelial secreted Wnt ligands maintain metabolic zonation in the adult murine liver but whether those ligands are necessary to initiate zonation in the immature liver has been only partially explored. Also, numerous non-metabolic proteins display zonated expression in the adult liver but it is not entirely clear if their localization requires endothelial Wnts. Here we used a novel transgenic mouse model to compare the spatial distribution of zonated non-metabolic proteins with that of typical zonated metabolic enzymes during liver maturation and after acute injury induced by carbon tetrachloride (CCl4). We also investigated how preventing Wnt ligand secretion from endothelial cells affects zonation patterns under homeostasis and after acute injury. Our study demonstrates that metabolic and non-metabolic zonation are established non-synchronously during maturation and regeneration and require multiple endothelial Wnt sources.


Assuntos
Capilares/metabolismo , Metabolismo Energético , Fígado/metabolismo , Proteínas Wnt/metabolismo , Fatores Etários , Animais , Biomarcadores , Tetracloreto de Carbono/efeitos adversos , Claudina-2/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Imunofluorescência , Expressão Gênica , Hepatócitos/metabolismo , Imuno-Histoquímica , Ligantes , Fígado/irrigação sanguínea , Camundongos , Camundongos Transgênicos , Transdução de Sinais
13.
J Transl Med ; 17(1): 158, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31092264

RESUMO

BACKGROUND: Telocytes play key roles in maintenance of organ/tissue function and prevention of organ injury. However, there are great challenges to investigate telocytes functions using primary telocytes, due to the difficulties of isolation, identification, and stability. The present study aims at constructing continuous cell strain of mouse lung telocyte cell line with stable characters by gene modification and investigating biological behaviors and responses of gene-modified telocytes to inflammation. METHODS: Mouse primary lung telocytes were isolated and identified using immune-labeling markers and immunoelectron microscopy. Primary telocytes were transformed with Simian vacuolating virus 40 small and large T antigen (SV40). Biological characters, behaviors morphology, and proliferation of those gene-modified telocytes were defined and monitored dynamically for 50 generations, as compared with primary lung telocytes. Cell cycle of mouse primary lung telocytes or gene-modified telocytes was detected by flow cytometry. RESULTS: Gene modified telocytes of generations 5, 10, 30 and 50 were observed with telopodes and also showed CD34 and ckit positive. Multiple cellular morphology were also observed on telocyte cell-line under monitor of celliq and enhanced cell proliferation were showed. SV40 transduction was also reduced apoptosis and increased the ratio of S and G2 phases in telocyte cell-line. CONCLUSION: We successfully constructed mouse lung telocyte cell-line which maintained the biological properties and behaviors as primary telocytes and could responses to inflammation induced by LPS. Thus, gene-modified lung telocytes, Telocyte Line, would provide a cell tool for researchers exploring the roles and applications of telocytes involved in physiological and pathological states in future.


Assuntos
Inflamação/genética , Pulmão/patologia , Telócitos/patologia , Animais , Biomarcadores/metabolismo , Morte Celular , Diferenciação Celular , Proliferação de Células , Feminino , Camundongos Endogâmicos BALB C , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Telócitos/metabolismo , Telócitos/ultraestrutura
14.
Am J Transl Res ; 11(4): 2280-2287, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31105835

RESUMO

AIMS: Postoperative cognitive dysfunction (POCD) is a neurological disorder associated with neuroinflammation. Connexin 43 (Cx43), an essential component of gap junction, plays a crucial role in neuroinflammation. The present study was designed to investigate the role of Cx43 in the process of POCD. METHODS: POCD model was established in aged mice with internal fixation of tibial fractures. Cognitive function was examined using the Morris water maze test. Hippocampus was collected for reverse transcription polymerase chain reaction (RT-PCR), western blotting, and immunofluorescence assays. RESULTS: In the water maze test, mice undergoing surgery took longer time to reach target platform than the controls. IL-1ß and TNF-α mRNA expressions in the hippocampus were significantly increased in surgery mice. Cx43 protein presence in the hippocampus was increased in the surgery group. Treatment of Gap26, a specific blocker of Cx43 hemichannel, reduced the Cx43 protein presence, decreased mRNA expressions of IL-1ß and TNF-α, and improved cognitive score in the maze test. CONCLUSION: Internal fixation of tibial fractures in aged mice induces Cx43 hemichannels opening and enhances neuroinflammation in the hippocampus, leading to cognitive impairment. Administration of Gap26 reduces neuroinflammation in the hippocampus and improves postoperative cognitive function.

15.
Acta Biochim Biophys Sin (Shanghai) ; 50(8): 817-825, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29924305

RESUMO

Mechanical ventilation (MV) is an important procedure for the treatment of patients with acute lung injury or acute respiratory distress syndrome in a clinical setting; however, MV can lead to severe complications, including ventilator-induced lung injury (VILI). Telocytes (TCs) can promote tissue repair following injury in the heart, kidneys, and other organs. The aim of this study was to investigate the role of TCs in VILI in mice and the associated mechanisms. By using in vivo studies in mice and in vitro studies in cells, we demonstrated that an airway injection of TCs can reduce the pulmonary inflammatory response and improve the lung function in mice with VILI and promote the proliferation of pulmonary vascular endothelial cells. We also demonstrated that the impact of TCs on VILI repair might partially due to vascular endothelial growth factor (VEGF) secreted by TCs upon VILI stimulation, and that VEGF could induce the proliferation of hemangioendothelioma endothelial cells (EOMA). Collectively, our results revealed novel functions of TCs in VILA repair and shed light on the complications that are caused by MV.


Assuntos
Pulmão/metabolismo , Telócitos/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Lipopolissacarídeos/farmacologia , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Respiração Artificial/efeitos adversos , Telócitos/transplante , Lesão Pulmonar Induzida por Ventilação Mecânica/etiologia , Lesão Pulmonar Induzida por Ventilação Mecânica/terapia
16.
Nat Cell Biol ; 20(1): 21-27, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29230018

RESUMO

CD8+ memory T (Tm) cells are fundamental for protective immunity against infections and cancers 1-5 . Metabolic activities are crucial in controlling memory T-cell homeostasis, but mechanisms linking metabolic signals to memory formation and survival remain elusive. Here we show that CD8+ Tm cells markedly upregulate cytosolic phosphoenolpyruvate carboxykinase (Pck1), the hub molecule regulating glycolysis, tricarboxylic acid cycle and gluconeogenesis, to increase glycogenesis via gluconeogenesis. The resultant glycogen is then channelled to glycogenolysis to generate glucose-6-phosphate and the subsequent pentose phosphate pathway (PPP) that generates abundant NADPH, ensuring high levels of reduced glutathione in Tm cells. Abrogation of Pck1-glycogen-PPP decreases GSH/GSSG ratios and increases levels of reactive oxygen species (ROS), leading to impairment of CD8+ Tm formation and maintenance. Importantly, this metabolic regulatory mechanism could be readily translated into more efficient T-cell immunotherapy in mouse tumour models.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Glicogênio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Melanoma Experimental/genética , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Neoplasias Cutâneas/genética , Ácido 3-Mercaptopropiônico/farmacologia , Transferência Adotiva , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/transplante , Ciclo do Ácido Cítrico/efeitos dos fármacos , Ciclo do Ácido Cítrico/genética , Ciclo do Ácido Cítrico/imunologia , Inibidores Enzimáticos/farmacologia , Feminino , Gluconeogênese/efeitos dos fármacos , Gluconeogênese/genética , Gluconeogênese/imunologia , Glucose/imunologia , Glicogênio/imunologia , Glicólise/efeitos dos fármacos , Glicólise/genética , Glicólise/imunologia , Homeostase/imunologia , Memória Imunológica , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NADP/imunologia , NADP/metabolismo , Via de Pentose Fosfato/efeitos dos fármacos , Via de Pentose Fosfato/genética , Via de Pentose Fosfato/imunologia , Fosfoenolpiruvato Carboxiquinase (GTP)/antagonistas & inibidores , Fosfoenolpiruvato Carboxiquinase (GTP)/imunologia , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/metabolismo
17.
Int Immunopharmacol ; 39: 229-235, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27494686

RESUMO

Sepsis is a serious disease that leads to severe inflammation, dysregulation of immune system, multi-organ failure and death. Innate response activator (IRA) B cells, which produce granulocyte-macrophage colony-stimulating factor (GM-CSF), protect against microbial sepsis. Lipid mediator lipoxin A4 (LXA4) exerts anti-inflammatory and immunoregulatory effects, and it has been reported that LXA4 receptor ALX/FPR2 is expressed on B cells. Here, we investigated the potential role of LXA4 on IRA B cells in lipopolysaccharide (LPS)-induced sepsis. We found that LXA4 significantly promoted the expansion of splenic IRA B cells and increased GM-CSF expression in splenic B cells with LPS stimulation. After splenectomy, LXA4 treatment did not change the serum or peritoneal IL-1ß, IL-6 and TNF-α levels in LPS-induced sepsis. LXA4 accelerated the migration of peritoneal B cells to spleen for their differentiation into IRA B cells, whereas this effect was independent of peritoneal macrophage. Furthermore, LXA4 enhanced the phosphorylation level of signal transducer and activator of transcription 5 (STAT5) in splenic B cells. These results suggest that LXA4 protects against LPS-induced sepsis by promoting the generation and migration of splenic IRA B cells, and the underlying molecular mechanism may be related to STAT5 activation. It might provide new insights and therapeutic approaches for treating sepsis.


Assuntos
Anti-Inflamatórios/uso terapêutico , Linfócitos B/efeitos dos fármacos , Imunidade Inata , Lipoxinas/uso terapêutico , Fator de Transcrição STAT5/metabolismo , Sepse/tratamento farmacológico , Animais , Linfócitos B/imunologia , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Imunidade Inata/efeitos dos fármacos , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Sepse/induzido quimicamente
18.
Cell Res ; 26(6): 713-27, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27167569

RESUMO

Developing novel approaches to reverse the drug resistance of tumor-repopulating cells (TRCs) or stem cell-like cancer cells is an urgent clinical need to improve outcomes of cancer patients. Here we show an innovative approach that reverses drug resistance of TRCs using tumor cell-derived microparticles (T-MPs) containing anti-tumor drugs. TRCs, by virtue of being more deformable than differentiated cancer cells, preferentially take up T-MPs that release anti-tumor drugs after entering cells, which in turn lead to death of TRCs. The underlying mechanisms include interfering with drug efflux and promoting nuclear entry of the drugs. Our findings demonstrate the importance of tumor cell softness in uptake of T-MPs and effectiveness of a novel approach in reversing drug resistance of TRCs with promising clinical applications.


Assuntos
Antineoplásicos/uso terapêutico , Micropartículas Derivadas de Células/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias de Tecidos Moles/patologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Doxorrubicina/farmacologia , Humanos , Camundongos Endogâmicos BALB C , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Derrame Pleural/patologia , Análise de Sobrevida
19.
Oncoimmunology ; 5(4): e1118599, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27141404

RESUMO

Despite identification of macrophages in tumors (tumor-associated macrophages, TAM) as potential targets for cancer therapy, the origin and function of TAM in the context of malignancy remain poorly characterized. Here, we show that microparticles (MPs), as a by-product, released by tumor cells act as a general mechanism to mediate M2 polarization of TAM. Taking up tumor MPs by macrophages is a very efficient process, which in turn results in the polarization of macrophages into M2 type, not only leading to promoting tumor growth and metastasis but also facilitating cancer stem cell development. Moreover, we demonstrate that the underlying mechanism involves the activation of the cGAS/STING/TBK1/STAT6 pathway by tumor MPs. Finally, in addition to murine tumor MPs, we show that human counterparts also possess consistent effect on human M2 polarization. These findings provide new insights into a critical role of tumor MPs in remodeling of tumor microenvironment and better understanding of the communications between tumors and macrophages.

20.
Biomaterials ; 89: 56-66, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26950165

RESUMO

Oncolytic viruses have been utilized for the treatment of various cancers. However, delivery of the viral particles to tumor cells remains a major challenge. Microparticles (MP) are vesicle forms of plasma membrane fragments of 0.1-1 µm in size that are shed by cells. We have previously shown the delivery of chemotherapeutic drugs using tumor cell-derived MPs (T-MP). Here we report that T-MPs can be utilized as a unique carrier system to deliver oncolytic adenoviruses to human tumors, leading to highly efficient cytolysis of tumor cells needed for in vivo treatment efficacy. This T-MP-mediated oncolytic virotherapy approach holds multiple advantages, including: 1) delivery of oncolytic adenovirus by T-MPs is able to avoid the antiviral effect of host antibodies; 2) delivery of oncolytic adenovirus by T-MPs is not limited by virus-specific receptor that mediates the entry of virus into tumor cells; 3) T-MPs are apt at delivering oncolytic adenoviruses to the nucleus of tumor cells as well as to stem-like tumor-repopulating cells for the desired purpose of killing them. These findings highlight a novel oncolytic adenovirus delivery system with highly promising clinical applications.


Assuntos
Adenoviridae/genética , Micropartículas Derivadas de Células/metabolismo , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Neoplasias/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/genética , Animais , Linhagem Celular Tumoral , Micropartículas Derivadas de Células/patologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia
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