Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Angew Chem Int Ed Engl ; 62(52): e202316647, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37968887

RESUMO

The development of ultra-long room-temperature phosphorescence (UL-RTP) in processable amorphous organic materials is highly desirable for applications in flexible displays, anti-counterfeiting, and bio-imaging. However, achieving efficient UL-RTP from amorphous materials remains a challenging task, especially with activation by visible light and a bright afterglow. Here we report a general and rational molecular-design strategy to enable efficient visible-light-excited UL-RTP by multi-esterification of a rigid large-plane phosphorescence core. Notably, multi-esterification minimizes the aggregation-induced quenching and accomplishes a 'four birds with one stone' possibility in the generation and radiation process of UL-RTP: i) shifting the excitation from ultraviolet light to blue-light through enhancing the transition dipole moment of low-lying singlet-states, ii) facilitating the intersystem crossing process through the incorporation of lone-pair electrons, iii) boosting the decay process of long-lived triplet excitons resulting from a significantly increased transition dipole moment, and iv) reducing the intrinsic triplet nonradiative decay by substitution of high-frequency vibrating hydrogen atoms. All these factors synergistically contribute to the most efficient and stable visible-light-stimulated UL-RTP (lifetime up to 2.01 s and efficiency up to 35.4 % upon excitation at 450 nm) in flexible films using multi-esterified coronene, which allows high-tech applications in single-component time-delayed white light-emitting diodes and information technology based on flashlight-activated afterglow encryption.

2.
Plant Biotechnol J ; 21(7): 1373-1382, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36920783

RESUMO

As a finite and non-renewable resource, phosphorus (P) is essential to all life and crucial for crop growth and food production. The boosted agricultural use and associated loss of P to the aquatic environment are increasing environmental pollution, harming ecosystems, and threatening future global food security. Thus, recovering and reusing P from water bodies is urgently needed to close the P cycle. As a natural, eco-friendly, and sustainable reclamation strategy, microalgae-based biological P recovery is considered a promising solution. However, the low P-accumulation capacity and P-removal efficiency of algal bioreactors restrict its application. Herein, it is demonstrated that manipulating genes involved in cellular P accumulation and signalling could triple the Chlamydomonas P-storage capacity to ~7% of dry biomass, which is the highest P concentration in plants to date. Furthermore, the engineered algae could recover P from wastewater almost three times faster than the unengineered one, which could be directly used as a P fertilizer. Thus, engineering genes involved in cellular P accumulation and signalling in microalgae could be a promising strategy to enhance P uptake and accumulation, which have the potential to accelerate the application of algae for P recovery from the water body and closing the P cycle.


Assuntos
Microalgas , Fósforo , Ecossistema , Água , Águas Residuárias
3.
Med Phys ; 50(4): 1975-1989, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36688628

RESUMO

PURPOSE: To develop a deep learning network that treats the three-dimensional respiratory motion signals as a whole and considers the inter-dimensional correlation between signals of different directions for accurate respiratory tumor motion prediction. METHODS: We propose a deep learning framework, named as LSTM-Global Temporal Convolution-External Attention Network (LGEANet). In LGEANet, we first feed each of the univariate time series into the Long Short-Term Memory (LSTM) module respectively and utilize the strength of the global temporal convolutional layer to discover the temporal pattern of the univariate signals from hidden states of the LSTM. Then, External attention is adopted to capture the dynamic dependence of the multiple time series. Also, a traditional autoregressive linear model in parallel to the non-linear neural network part was integrated to mitigate the scale insensitivity of the networks. A total of 304 motion traces for 31 patients are acquired from a public dataset in the experiments and four representative cases were selected for model evaluation. The respiratory signals were sampled at intervals of about 37.5 ms (26 frames per second) for an average duration of 71 min. RESULTS: The proposed LGEANet achieved better performance with higher empirical correlation coefficient value (CORRs) and lower mean absolute error value (MAEs) and relative squared error value (RSEs) than other investigated models. For the four representative datasets, when the response time is less than 231 ms, the model can achieve CORRs more than 0.96. And the averaged position error reduction by using the proposed model was about 67% in the superior-inferior (SI) direction, 41% in the anterior-posterior (AP) direction and 38% in the right-left (RL) direction compared to that without prediction. The proposed network achieved the greatest error reduction in the SI direction, which is the main direction of tumor motion. CONCLUSIONS: The LGEANet achieves promising performance in minimizing the prediction error due to system latencies during real-time tumor motion tracking.


Assuntos
Neoplasias , Redes Neurais de Computação , Humanos , Movimento (Física) , Modelos Lineares
4.
J Affect Disord ; 322: 118-124, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36395987

RESUMO

BACKGROUND: Suicidal ideation (SI) is severe comorbidity of depression that has been extensively studied in the past. Residence differences between SI have rarely been systematically studied, especially in parental rearing behavior. This large-scale explored the residence differences in the prevalence and correlation of SI adolescent patients with depression. METHODS: A total of 1417 patients with depression were recruited, and their demographic data and clinical data were collected. The Children's Depression Inventory (CDI) and the Egna Minnen Beträffande Uppfostran (EMBU) scale were used to assess depression, and parental rearing behavior, respectively. RESULTS: The prevalence of suicidal ideation was higher in urban patients than in rural patients (43.7 % vs.37.7 %, P < 0.05). Patients with SI scored higher on total CDI scores, parental punishment, parental rejection, and paternal overprotection compared to their respective patients without SI. In the urban group, patients with SI had lower parental emotional warmth scores and higher parental intervention scores compared to patients without SI. Logistic regression analysis showed that total CDI score, gender, alcohol consumption, father's emotional warmth, father's rejection, and mother's intervention were significantly associated with SI in urban patients (P < 0.05); total CDI score and mother's rejection were significantly associated with SI in rural patients (P < 0.05). LIMITATIONS: No causal relationship could be drawn due to the cross-sectional design. CONCLUSIONS: The results of this study showed significant residential differences in risk and associated factors for SI among adolescents with depression. Focusing on the parenting styles of adolescent patients can help with the early identification and intervention of SI.


Assuntos
Depressão , Ideação Suicida , Criança , Humanos , Adolescente , Prevalência , Depressão/epidemiologia , Estudos Transversais , Poder Familiar , China/epidemiologia
5.
Sci Total Environ ; 852: 158403, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36057314

RESUMO

Improving energy efficiency and lowering carbon emissions are of great importance to realize the "dual carbon" goal of carbon peak and carbon neutrality. Digital economy is a new engine of economic development, but whether or how it affects energy efficiency and carbon emissions are unclear. Utilizing panel data of China's 30 provinces from 2012 to 2019, this study empirically explores the relationships among digital economy, energy efficiency, and carbon emissions. Meanwhile, from the perspective of energy efficiency, applying mediation models and panel threshold model, it analyzes the direct, indirect, and nonlinear influencing mechanisms of digital economy on carbon emissions. The results reflect that the development of digital economy in China intensifies carbon emissions. Energy efficiency serves as a vital partial mediator between the two. The enhancement of energy efficiency can lower carbon emissions. However, the development of digital economy is not conducive to improving energy efficiency, thereby, indirectly increasing carbon emissions. The mediating effect of energy efficiency accounts for 30.58 % of the total effect of digital economy on carbon emissions. Meanwhile, taking energy efficiency into account, the impact of digital economy on carbon emissions has a significant double-threshold effect and presents an N-shaped trend. [0.824, 0.912] is the optimal range of energy efficiency, within which the growth of the digital economy can empower carbon emission abatement to some extent. In addition, the expansion of population size, the coal-based energy consumption structure, and the industrial structure significantly increase carbon emissions. The improvements in living standards and environmental regulations can help to decrease carbon emissions, but the emission abatement effects are not significant. Those conclusions reveal the importance of optimizing the level and quality of digital economy and adopting differentiated digital economy development policies based on energy efficiency to achieve carbon emission reduction.


Assuntos
Carbono , Conservação de Recursos Energéticos , Carbono/análise , Desenvolvimento Econômico , Dióxido de Carbono/análise , China , Carvão Mineral
6.
J Zhejiang Univ Sci B ; 23(6): 461-480, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35686526

RESUMO

The negative effects of low temperature can readily induce a variety of diseases. We sought to understand the reasons why cold stress induces disease by studying the mechanisms of fine-tuning in macrophages following cold exposure. We found that cold stress triggers increased macrophage activation accompanied by metabolic reprogramming of aerobic glycolysis. The discovery, by genome-wide RNA sequencing, of defective mitochondria in mice macrophages following cold exposure indicated that mitochondrial defects may contribute to this process. In addition, changes in metabolism drive the differentiation of macrophages by affecting histone modifications. Finally, we showed that histone acetylation and lactylation are modulators of macrophage differentiation following cold exposure. Collectively, metabolism-related epigenetic modifications are essential for the differentiation of macrophages in cold-stressed mice, and the regulation of metabolism may be crucial for alleviating the harm induced by cold stress.


Assuntos
Resposta ao Choque Frio , Epigênese Genética , Acetilação , Animais , Macrófagos/metabolismo , Camundongos , Mitocôndrias/metabolismo
7.
Cell Death Dis ; 13(4): 316, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35393404

RESUMO

ULK1 is crucial for initiating autophagosome formation and its activity is tightly regulated by post-translational modifications and protein-protein interactions. In the present study, we demonstrate that TMEM189 (Transmembrane protein 189), also known as plasmanylethanolamine desaturase 1 (PEDS1), negatively regulates the proteostasis of ULK1 and autophagy activity. In TMEM189-overexpressed cells, the formation of autophagesome is impaired, while TMEM189 knockdown increases cell autophagy. Further investigation reveals that TMEM189 interacts with and increases the instability of ULK1, as well as decreases its kinase activities. The TMEM189 N-terminal domain is required for the interaction with ULK1. Additionally, TMEM189 overexpression can disrupt the interaction between ULK1 and TRAF6, profoundly impairs K63-linked polyubiquitination of ULK1 and self-association, leading to the decrease of ULK1 stability. Moreover, in vitro and in vivo experiments suggest that TMEM189 deficiency results in the inhibition of tumorigenicity of gastric cancer. Our findings provide a new insight into the molecular regulation of autophagy and laboratory evidence for investigating the physiological and pathological roles of TMEM189.


Assuntos
Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Autofagia , Enzimas de Conjugação de Ubiquitina , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Fosforilação , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitinação
8.
Cell Tissue Bank ; 23(1): 101-118, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33837877

RESUMO

Vascular network reconstruction plays a pivotal role in the axonal regeneration and nerve function recovery after peripheral nerve injury. Increasing evidence indicates that Schwann cells (SCs) can promote nerve function repair, and the beneficial effects attributed to SCs therapy may exert their therapeutic effects through paracrine mechanisms. Recently, the previous research of our group demonstrated the promising neuroregenerative capacity of Schwann-like cells (SCLCs) derived from differentiated human embryonic stem cell-derived neural stem cells (hESC-NSCs) in vitro. Herein, the effects of SC-like cell conditioned medium (SCLC-CM) on angiogenesis and nerve regeneration were further explored. The assays were performed to show the pro-angiogenic effects of SCLC-CM, such as promoted endothelial cell proliferation, migration and tube formation in vitro. In addition, Sprague-Dawley rats were treated with SCLC-CM after sciatic nerve crush injury, SCLC-CM was conducive for the recovery of sciatic nerve function, which was mainly manifested in the SFI increase, the wet weight ratio of gastrocnemius muscle, as well as the number and thickness of myelin. The SCLC-CM treatment reduced the Evans blue leakage and increased the expression of CD34 microvessels. Furthermore, SCLC-CM upregulated the expressions of p-Akt and p-mTOR in endothelial cells. In conclusion, SCLC-CM promotes angiogenesis and nerve regeneration, it is expected to become a new treatment strategy for peripheral nerve injury.


Assuntos
Células Endoteliais , Traumatismos dos Nervos Periféricos , Animais , Meios de Cultivo Condicionados/farmacologia , Regeneração Nervosa , Traumatismos dos Nervos Periféricos/metabolismo , Traumatismos dos Nervos Periféricos/terapia , Ratos , Ratos Sprague-Dawley , Células de Schwann , Nervo Isquiático
9.
Phys Med Biol ; 66(14)2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34181588

RESUMO

Dynamic CT myocardial perfusion imaging (DCT-MPI) is a reliable examination tool for the assessment of myocardium and vascular, while its special scan protocol may result in excessive radiation exposure to patients and inevitable inter-frame motion. Lowering the tube current is a simple way to reduce radiation exposure. However, low mAs will certainly cause severe image noise, thus may further impact the accuracy of functional hemodynamic parameters, which are used for the assessment of blood supply. In this work, we present a novel scheme applying motion compensation and local low rank regularization (MC-LLR) for obtaining high quality motion compensated DCT-MPI images. Specifically, motion compensation by using robust data decomposition registration (RDDR) was introduced. Robust principal component analysis coupled with optical flow-based registration algorithm were used in RDDR. Then, the local low rank constraint on the motion compensated time series images was applied for the DCT-MPI reconstruction. One healthy mini pig and two patient datasets were used to evaluate the proposed MC-LLR algorithm. Results show that the present method achieved satisfactory image quality with higher CNRs, smaller rRMSEs, and more accurate hemodynamic parameter maps.


Assuntos
Imagem de Perfusão do Miocárdio , Tomografia Computadorizada por Raios X , Algoritmos , Animais , Humanos , Processamento de Imagem Assistida por Computador , Miocárdio , Perfusão , Imagens de Fantasmas , Suínos , Porco Miniatura
10.
J Biomed Nanotechnol ; 17(2): 291-302, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33785099

RESUMO

Schwann cells promote axonal regeneration following peripheral nerve injury. However, in terms of clinical treatment, the therapeutic effects of Schwann cells are limited by their source. The transmission of microvesicles from neuroglia cells to axons is a novel communication mechanism in axon regeneration.To evaluate the effect of microvesicles released from Schwann-like cells on axonal regeneration, neural stem cells derived from human embryonic stem cells differentiated into Schwann-like cells, which presented a typical morphology and characteristics similar to those of schwann cells. The glial markers like MBP, P0, P75NTR, PMP-22, GFAP, HNK-1 and S100 were upregulated, whereas the neural stem markers like NESTIN, SOX1 and SOX2 were significantly downregulated in schwann-like cells. Microvesicles enhanced axonal growth in dorsal root ganglia neurons and regulated GAP43 expression in neuron-like cells (N2A and PC12) through the PTEN/PI3 K/Akt signaling pathway. A 5 mm section of sciatic nerve was transected in Sprague-Dawley rats. With microvesicles transplantation, regenerative nerves were evaluated after 6 weeks. Microvesicles increased sciatic function index scores, delayed gastrocnemius muscle atrophy and elevated ßIII-tubulin-labeled axons in vivo. Schwann-like cells serve as a convenient source and promote axonal growth by secreting microvesicles, which may potentially be used as bioengineering materials for nerve tissue repair.


Assuntos
Axônios , Regeneração Nervosa , Animais , Materiais Biocompatíveis , Ratos , Ratos Sprague-Dawley , Células de Schwann , Nervo Isquiático
11.
Front Plant Sci ; 12: 792832, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35126418

RESUMO

Plant carotenoid cleavage oxygenase (CCO) is an enzyme that catalyzes the synthesis of carotenoids and participates in many important physiological functions. The plant CCOs exist in two forms, namely carotenoid cleavage dioxygenase (CCD) and nine-cis epoxide carotenoid dioxygenase (NCED). Although studies have shown that this gene family has been identified in many species, such as Arabidopsis, grape, and tomato, the evolutionary origin of the CCO family and the expression pattern of pepper genes in response to H2O2 and other abiotic stresses are still unclear. In this study, we used the bioinformatics method to identify and analyze the members of the CCO gene family from pepper and other 13 plants from lower to higher plant species based on the whole genome sequence. A total of 158 CCO genes were identified in different plant species and further divided into two groups (e.g., groups I and II). The former was subdivided into CCD7 and CCD8 and have independent evolutionary origins, respectively, while the latter was subdivided into CCD1, CCD4, CCD-like, and NCED, which may have come from a common ancestor. In addition, the results of RNA-seq showed that the expression patterns of pepper CaCCO genes were different in the tissues tested, and only few genes were expressed at high levels such as CaCCD1a, CaCCD4a, CaNCED3, and CaCCD1b. For hydrogen peroxide (H2O2) and other abiotic stresses, such as plant hormones, heat, cold, drought, and NaCl treatments, induction of about half of the CaCCO genes was observed. Moreover, the expression patterns of CaCCOs were further investigated under heat, cold, drought, and NaCl treatments using quantitative real-time PCR (qRT-PCR), and most members were responsive to these stresses, especially some CaCCOs with significant expression changes were identified, such as CaCCD4c, CaCCD-like1, CaCCD8, and CaCCD1b, suggesting the important roles of CaCCOs in abiotic stress responses. All these results will provide a valuable analytical basis for understanding the evolution and functions of the CCO family in plants.

12.
Cell Death Dis ; 11(9): 810, 2020 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-32980859

RESUMO

Autophagy is a highly conserved lysosome-dependent degradation system in eukaryotic cells. This process removes long-lived intracellular proteins, damaged organelles, and recycles biological material to maintain cellular homeostasis. Dysfunction of autophagy triggers a wide spectrum of human diseases, including cancer and neurodegenerative diseases. In the present study, we show that RNF115, an E3 ubiquitin ligase, regulates autophagosome-lysosome fusion and autophagic degradation under both nutrient-enriched and stress conditions. Depletion of the RNF115 gene caused the accumulation of autophagosomes by impairing fusion with lysosomes, which results in an accumulation of autophagic substrates. Further investigation suggests that RNF115 interacts with STX17 and enhances its stability, which is essential for autophagosome maturation. Importantly, we provide in vitro and in vivo evidence that RNF115 inactivation inhibits the tumorigenesis and metastasis of BGC823 gastric cancer cells. We additionally show that high expression levels of RNF115 mRNA correlate with poor prognosis in gastric cancer patients. These findings indicate that RNF115 may play an evolutionarily conserved role in the autophagy pathway, and may act to maintain protein homeostasis under physiological conditions. These data demonstrate the need to further evaluate the potential therapeutic implications of RNF115 in gastric cancer.


Assuntos
Autofagossomos/metabolismo , Autofagia/genética , Neoplasias Gástricas/genética , Ubiquitina-Proteína Ligases/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias Gástricas/patologia , Transfecção
13.
Stem Cells Dev ; 29(16): 1084-1095, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32560594

RESUMO

Chronic persistent inflammation is thought to impede axon regeneration and cause demyelinating disease also with neuropathic pain, leading to more severe dysfunction after peripheral nerve injury. Increasing evidence indicates that neural stem cells (NSCs) have immunomodulatory effects, and previous studies have shown that many of the beneficial effects attributed to stem cell therapy may exert their therapeutic effects through paracrine mechanisms. In this research, the repairing effect of NSC-conditioned medium (NSC-CM) on sciatic nerve injury and its mechanism of repair were further explored. The present research showed that NSC-CM promoted histopathological and functional recovery after crush injury in rats, and what counts is that NSC-CM inhibited the inflammation of sciatic nerve in the late stage of injury. NSC-CM significantly downregulated the infiltration of proinflammatory factors [tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and IL-1ß] as well as decreased the CD68 inflammatory macrophages infiltrating in the sciatic nerve. In addition, to study the effect of NSC-CM on the inflammatory state of macrophages in vitro, lipopolysaccharide (LPS) was used to induce the proinflammation of macrophages. The results showed that NSC-CM decreased the expression of macrophage proinflammatory-related proteins (IL-6, IL-1ß, TNF-α, inducible nitric oxide synthase) induced by LPS. The activation of Sirt-1 signaling in macrophages effectively countered the proinflammation induced by LPS in the presence of NSC-CM. Using Sirt-1-specific inhibitor EX527 partially weakened the anti-inflammatory effect of NSC-CM. Altogether, this study demonstrated for the first time that NSC-CM promotes functional recovery after sciatic nerve crush injury in vivo and also inhibits the inflammation in activated macrophages by activating Sirt-1 signaling pathway in vitro.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Inflamação/patologia , Macrófagos/patologia , Células-Tronco Neurais/metabolismo , Recuperação de Função Fisiológica , Nervo Isquiático/lesões , Transdução de Sinais , Sirtuína 1/metabolismo , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , NF-kappa B/metabolismo , Regeneração Nervosa/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Remielinização/efeitos dos fármacos , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/patologia , Nervo Isquiático/fisiopatologia , Transdução de Sinais/efeitos dos fármacos
14.
Life Sci ; 253: 117750, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32380078

RESUMO

AIM: Osteoarthritis (OA) is the main cause of disability and joint replacement surgery in the elderly. As a crucial cell survival mechanism, autophagy has been reported to decrease in OA. PHF23 is a new autophagy inhibitor which was first reported by us previously. This study aimed to explore the anti-autophagic mechanism of PHF23 to make it a possible therapeutic target of OA. MAIN METHOD: Lentiviral vectors specific to PHF23 were used on chondrocytes (C28/I2) to establish PHF23 overexpressed or knockdown stable cell strains. Interleukin (IL)-1ß (10 ng/mL) and chloroquine (CQ, 25 uM) were used as an inducer of OA and inhibitor of lysosome, respectively. Autophagy was evaluated by autophagosome formation using transmission electron microscopy (TEM) and western blot analysis of P62 and LC3B on different groups of cells. Effects of PHF23 on OA were evaluated by collagen II immunofluorescent staining and western blot analysis of OA-associated proteins MMP13 and ADAMTS5. Effects of PHF23 on AMPK and mTOR/S6K pathways and mitophagy were determined by western blot analysis. KEY FINDINGS: Knockdown of PHF23 enhanced IL-1ß-induced autophagy, while overexpression of PHF23 exerted the opposite effect. Knockdown of PHF23 protected chondrocytes against IL-1ß-induced OA by decreasing the levels of OA-associated proteins and increasing expression of Collagen II. Knockdown of PHF23 also increased mitophagy level and altered the phosphorylation levels of AMPK, mTOR, and S6K. SIGNIFICANCE: PHF23 downregulates autophagy, mitophagy in IL-1ß-induced OA-like chondrocytes and alters the activities of AMPK and mTOR/S6K, which suggests that PHF23 may be a possible therapeutic target for OA.


Assuntos
Autofagia/genética , Condrócitos/patologia , Proteínas de Homeodomínio/genética , Osteoartrite/patologia , Proteínas Quinases Ativadas por AMP/metabolismo , Sobrevivência Celular/genética , Células Cultivadas , Colágeno Tipo II/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Interleucina-1beta/administração & dosagem , Lisossomos/metabolismo , Osteoartrite/genética , Proteínas Quinases S6 Ribossômicas/metabolismo , Serina-Treonina Quinases TOR/metabolismo
15.
Cell Tissue Bank ; 21(2): 233-248, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32052220

RESUMO

Injured nerves cannot regenerate on their own, and a lack of engraftable human nerves has been a major obstacle in cell-based therapies for regenerating damaged nerves. A monolayer culture approach to obtain adherent neural stem cells from human embryonic stem cells (hESC-NSCs) was established, and the greatest number of stemness characteristics were achieved by the eighth generation of hESC-NSCs (P8 hESC-NSCs). To overcome deficits in cell therapy, we used microvesicles secreted from P8 hESC-NSCs (hESC-NSC-MVs) instead of entire hESC-NSCs. To investigate the therapeutic efficacy of hESC-NSC-MVs in vitro, hESC-NSC-MVs were cocultured with dorsal root ganglia to determine the length of axons. In vivo, we transected the sciatic nerve in SD rats and created a 5-mm gap. A sciatic nerve defect was bridged using a silicone tube filled with hESC-NSC-MVs (45 µg) in the MVs group, P8 hESC-NSCs (1 × 106 single cells) in the cell group and PBS in the control group. The hESC-NSC-MVs group showed better morphological recovery and a significantly greater number of regenerated axons than the hESC-NSCs group 12 weeks after nerve injury. These results indicated that the hESC-NSC-MVs group had the greatest ability to repair and reconstruct nerve structure and function. As a result, hESC-NSC-MVs may have potential for applications in the field of nerve regenerative repair.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Regeneração Nervosa/fisiologia , Células-Tronco Neurais/metabolismo , Nervo Isquiático/fisiologia , Animais , Animais Recém-Nascidos , Axônios/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular , Linhagem Celular , Gânglios Espinais/metabolismo , Humanos , Músculos/fisiologia , Nanopartículas/química , Células-Tronco Neurais/citologia , Ratos Sprague-Dawley
16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-815387

RESUMO

Objective@#To evaluate effects of mobile health intervention on vegetables and fruits intakes, screen time, body mass index, BMI Z score and waist circumference in children and adolescents.@*Methods@#The literature search was performed to find articles published up to December 2018 in the databases: PubMed, Embase, Cochrane Library, CNKI, Wanfang. The articles focusing on the keywords of "prevention" "children" "adolescents" "obesity" "weight loss" "m-Health" "mobile phone" "mobile application" "mobile techonology" "cell phone" "smartphone" "mobile apps" for the delivery of children and adolescents obesity interventions were included. Stata 13.0 software was used for Meta-analysis.@*Results@#A total of 15 studies were included, and mobile health had an effect on the vegetables and fruits intakes and screen time for children and adolescents. Mobile health was more effective in the intervention participants compared to controls, the standardized mean difference (SMD) and 95%CI were 0.54 (95%CI=0.27-0.81) and -0.32(95%CI=-0.47--0.18),respectively. However, no statistical differences in the BMI, BMI Z score and waist circumference were found between intervention and control groups.@*Conclusion@#The effect of mobile health intervention on obesity in children and adolescents needs more long-term follow-up and larger sample size studies to clarify.

17.
Stem Cells Int ; 2019: 6452684, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772588

RESUMO

Myocardial reperfusion injury (MRI) induced by cardiomyocyte apoptosis plays an important role in the pathogenesis of a variety of cardiovascular diseases. New MRI treatments involving stem cells are currently being developed because these cells may exert their therapeutic effects primarily through paracrine mechanisms. Microvesicles (MVs) are small extracellular vesicles that have become the key mediators of intercellular communication. MVs derived from stem cells have been reported to play an important role in MRI. In this article, we attempted to explore the mechanisms by which MVs derived from human embryonic neural stem cells (hESC-NSC-derived MVs) rescue MRI. hESCs were differentiated into NSCs, and MVs were isolated from their supernatants by ultracentrifugation. H2O2 was used to induce apoptosis in HL-1 cardiomyocytes. Cell viability was detected by using the CCK-8 assay, apoptosis was detected by Annexin V-FITC/PI staining, and apoptosis-related proteins and signalling pathway-related proteins were detected by western blot analysis. Autophagic flux was measured using the tandem fluorescent mRFG-GFP-LC3 assay. Transmission electron microscopy and western blot analysis were adopted to evaluate autophagy levels. hESC-NSC-derived MVs increased the autophagy and inhibited the apoptosis of HL-1 cells exposed to H2O2 for 3 h in a dose-dependent manner. Additionally, hESC-NSC-derived MVs contained high levels of heat shock protein 70 (HSP-70), which can increase the level of HSP-70 in cells. Moreover, the same effect could be achieved by heat shock preconditioning of HL-1 cells overexpressing HSP-70. The benefits of NSC-MVs may be due to the involvement of AKT and mTOR signalling pathways. Importantly, hESC-NSC-derived MVs stimulated the activation of the AKTand mTOR signalling pathway in those cells by transporting HSP-70. Our results suggest that hESC-NSC-derived MVs inhibit the apoptosis of HL-1 cardiomyocytes by promoting autophagy and regulating AKT and mTOR via transporting HSP-70. However, this hypothesis requires in vivo confirmation.

18.
J Mater Sci Mater Med ; 30(7): 82, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273463

RESUMO

Axon regeneration and functional recovery after peripheral nerve injury remains a clinical challenge. Injury leads to axonal disintegration after which Schwann cells (SCs) and macrophages re-engage in the process of regeneration. At present, biomaterials are regarded as the most promising way to repair peripheral nerve damage. As a natural material, keratin has a wide range of sources and has good biocompatibility and biodegradability. Here, a keratin was extracted from human hair by reducing method and a keratin sponge with porous structure was obtained by further processing. The results suggested that keratin can promote cell adhesion, proliferation, migration as well as the secretion of neurotrophic factors by SCs and the regulation of the expression of macrophage inflammatory cytokines in vitro. We report for the first time that human hair keratin can promote the extension of axon in DRG neurons. The motor deficits caused by a sciatic nerve crush injury were alleviated by keratin sponge dressing in vivo. Thus, keratin has been identified as a valuable biomaterial that can enhance peripheral nerve regeneration.


Assuntos
Cabelo/química , Queratinas Específicas do Cabelo/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Nervos Periféricos/efeitos dos fármacos , Nervo Isquiático/lesões , Animais , Axônios/efeitos dos fármacos , Materiais Biocompatíveis , Adesão Celular , Linhagem Celular , Movimento Celular , Proliferação de Células , Citocinas/metabolismo , Humanos , Inflamação , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Neurônios/metabolismo , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Células de Schwann/efeitos dos fármacos , Cicatrização
19.
Biosci Biotechnol Biochem ; 83(7): 1227-1238, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31021705

RESUMO

Here we have explored the effect of neoagarotetraose (NAT) on liver injury caused by intense exercise. Our results showed that NAT treatment obviously decreased liver weight (p < 0.01), improved the liver morphological structure, decreased ALT level (p < 0.05) and endotoxin (LPS) (p < 0.01). In addition, NAT could regulate bile acid profiles in feces and serum of mice, which indicated the potential of liver function, suggesting that NAT was effective to relieve intense exercise-induced liver injury. NAT could regulate the expression of colon genes. NAT tended to alter the microbial composition of mice under intense exercise. We uncovered the network interactions between liver traits and microbial communities in NAT treatment mice. Interestingly, our data indicated that intense exercise-induced liver injury may be related to Clostridiales. In summary, these results demonstrated that NAT relieved liver injury induced by intense exercise may be related to gut microbiota.


Assuntos
Galactosídeos/farmacologia , Fígado/lesões , Oligossacarídeos/farmacologia , Condicionamento Físico Animal , Administração Oral , Animais , Colo/metabolismo , Galactosídeos/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligossacarídeos/administração & dosagem , Transcriptoma
20.
Biochem Biophys Res Commun ; 513(3): 663-668, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-30982575

RESUMO

Endoplasmic reticulum membrane protein complex subunit 6 (EMC6), also known as transmembrane protein 93 (transmembrane protein 93, TMEM93), is an autophagy-related protein. EMC6 overexpression inhibits cancer cell growth and induces apoptosis, but the interaction partners of EMC6 and its cellular responsibilities remain incompletely understood. In this study, we report that adenovirus-mediated ectopic overexpression of EMC6 (Ad5-EMC6) in BGC823 and SGC7901 gastric cancer cells decreases the activity of ERK1/2, down-regulates the levels of BCL-2 protein and phosphorylated BCL-2, increases the expression of tBID and BAX, and decreases mitochondrial membrane potential and subsequently leading to cell apoptosis. In a xenograft tumor model, we found that Ad5-EMC6 impairs the tumorigenesis of SGC7901 gastric cancer cells in nude mice. Additionally, Ad5-EMC6 enhances the sensitivity of gastric cancer cells to the chemotherapeutic drug etoposide. Collectively, these results demonstrate that EMC6-induced apoptosis of gastric cancer cells occurs at least partially through the mitochondrial-mediated apoptosis pathway. Our study suggests a rational basis for the potential clinical application of Ad5-EMC6 in gastric cancer.


Assuntos
Carcinogênese/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/patologia , Neoplasias Gástricas/metabolismo , Animais , Apoptose , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Potencial da Membrana Mitocondrial , Proteínas de Membrana/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Regulação para Cima
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...