Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
4,753
result(s) for
"Li, Bowen"
Sort by:
Latent but not absent: The ‘long tail’ nature of rural special education and its dynamic correction mechanism
by
Luo, Ji
,
Li, Bowen
,
Li, Guangqin
in
Administrative expenses
,
Charts of accounts
,
Children with disabilities
2021
The ‘long tail’ nature of rural special education (RSE) suggests that it simultaneously possesses the private nature of discreteness and the public nature of externalities, which can easily cause provision insufficiency. However, this mismatch may have a dynamic intertemporal correction mechanism impacted by different expenditures of supply sectors (governments and other social sectors). This paper uses different models and data from 30 provinces in China from 2003–2014 to analyze this dynamic correction mechanism. This research finds that different kinds of expenditures from different suppliers have divergent effects on this correction. Capital expenses (especially infrastructure construction) have significantly positive effects on the correction, but administrative expenses have significant dual effects on the correction. These effects may be caused by the various governance efficiencies and motivations of all stakeholders in RSE. This paper concludes that we should pay more attention to the accurate recognition and effective satisfaction of RSE affected by the governance efficiency and motivation of different suppliers to achieve this dynamic correction.
Journal Article
Gastric cancer-derived exosomal miR-519a-3p promotes liver metastasis by inducing intrahepatic M2-like macrophage-mediated angiogenesis
2022
Background
Liver metastasis (LM) is a major obstacle to the prognosis of gastric cancer (GC) patients, but the molecular mechanism underlying gastric cancer liver metastasis (GC-LM) remains unknown. Exosomes have been identified as an important mediator of communication between tumor cells and the microenvironment. Therefore, we sought to investigate the effects of primary GC cells on the liver microenvironment and the role of exosomal microRNAs (exo-miRNA) in GC-LM.
Methods
Sequential differential centrifugation, transmission electron microscopy and NanoSight analysis were used to extract and characterize exosomes. MicroRNA sequencing in GC-derived exosomes and mRNA sequencing in PMA-treated THP-1 cells were used to identify differentially expressed miRNAs in exosomes and the functional targets of exosomal miR-519a-3p (exo-miR-519a-3p) in macrophages, respectively. Tracing and internalization of exosomes and transfer of exo-miR-519a-3p were observed by immunofluorescence. Tubule formation assays, aortic ring assays, and exosome-educated GC-LM model were used to investigate the roles of GC-derived exosomes and exo-miR-519a-3p in angiogenesis and GC-LM. Luciferase reporter assay, qRT-PCR, Western blot, ELISA, flow cytometry and immunofluorescence were used to investigate the regulatory mechanism of exo-miR-519a-3p at GC-LM.
Results
The expression level of miR-519a-3p in serum exosomes was significantly higher in GC-LM patients than in patients without LM, and high expression of exo-miR-519a-3p indicates a worse prognosis. GC-derived exosomes are mainly accumulated in the liver and internalized by intrahepatic macrophages. Mechanistically, exo-miR-519a-3p activates the MAPK/ERK pathway by targeting DUSP2, thereby causing M2-like polarization of macrophages. M2-like polarized macrophages accelerate GC-LM by inducing angiogenesis and promoting intrahepatic premetastatic niche formation.
Conclusions
Our results indicate that exo-miR-519a-3p plays a critical role in mediating crosstalk between primary GC cells and intrahepatic macrophages and is a potential therapeutic target for GC-LM.
Journal Article
Cold and hot tumors: from molecular mechanisms to targeted therapy
2024
Immunotherapy has made significant strides in cancer treatment, particularly through immune checkpoint blockade (ICB), which has shown notable clinical benefits across various tumor types. Despite the transformative impact of ICB treatment in cancer therapy, only a minority of patients exhibit a positive response to it. In patients with solid tumors, those who respond well to ICB treatment typically demonstrate an active immune profile referred to as the “hot” (immune-inflamed) phenotype. On the other hand, non-responsive patients may exhibit a distinct “cold” (immune-desert) phenotype, differing from the features of “hot” tumors. Additionally, there is a more nuanced “excluded” immune phenotype, positioned between the “cold” and “hot” categories, known as the immune “excluded” type. Effective differentiation between “cold” and “hot” tumors, and understanding tumor intrinsic factors, immune characteristics, TME, and external factors are critical for predicting tumor response and treatment results. It is widely accepted that ICB therapy exerts a more profound effect on “hot” tumors, with limited efficacy against “cold” or “altered” tumors, necessitating combinations with other therapeutic modalities to enhance immune cell infiltration into tumor tissue and convert “cold” or “altered” tumors into “hot” ones. Therefore, aligning with the traits of “cold” and “hot” tumors, this review systematically delineates the respective immune characteristics, influencing factors, and extensively discusses varied treatment approaches and drug targets based on “cold” and “hot” tumors to assess clinical efficacy.
Journal Article
Modulation of redox homeostasis: A strategy to overcome cancer drug resistance
2023
Cancer treatment is hampered by resistance to conventional therapeutic strategies, including chemotherapy, immunotherapy, and targeted therapy. Redox homeostasis manipulation is one of the most effective innovative treatment techniques for overcoming drug resistance. Reactive oxygen species (ROS), previously considered intracellular byproducts of aerobic metabolism, are now known to regulate multiple signaling pathways as second messengers. Cancer cells cope with elevated amounts of ROS during therapy by upregulating the antioxidant system, enabling tumor therapeutic resistance via a variety of mechanisms. In this review, we aim to shed light on redox modification and signaling pathways that may contribute to therapeutic resistance. We summarized the molecular mechanisms by which redox signaling-regulated drug resistance, including altered drug efflux, action targets and metabolism, enhanced DNA damage repair, maintained stemness, and reshaped tumor microenvironment. A comprehensive understanding of these interrelationships should improve treatment efficacy from a fundamental and clinical research point of view.
Journal Article
A novel protein encoded by circMAPK1 inhibits progression of gastric cancer by suppressing activation of MAPK signaling
2021
Background
A novel type of noncoding RNA, circRNA has been reported to participate in the occurrence and development of diseases through many mechanisms. The MAPK pathway is a common signal transduction pathway involved in cell proliferation, inflammation and apoptosis and plays a particularly important role in cancers. However, the role of circRNAs related to the MAPK pathway in gastric cancer has not been explored.
Methods
A bioinformatics analysis was performed to profile and identify the circRNAs involved in the MAPK pathway in gastric cancer. The tumor-suppressive role of circMAPK1 was confirmed both in vitro and in vivo. Mass spectrometry, Western blot and immunofluorescence staining assays were used to validate the existence and expression of MAPK1–109aa. The molecular mechanism of circMAPK1 was investigated by mass spectrometry and immunoprecipitation analyses.
Results
In this study, we identified that circMAPK1 (hsa_circ_0004872) was downregulated in gastric cancer tissues compared with adjacent normal tissues. Importantly, lower circMAPK1 expression predicted poor survival in GC patients. CircMAPK1 inhibited the proliferation and invasion of gastric cancer cells in vitro and in vivo. Next, we found that circMAPK1 encoded a novel protein with 109 amino acids in length. Through a series of functional experiments, we confirmed that circMAPK1 exerted a tumor-suppressing effect via the encoded protein MAPK1–109aa. Mechanistically, the tumor suppressor MAPK1–109aa inhibited the phosphorylation of MAPK1 by competitively binding to MEK1, thereby suppressing the activation of MAPK1 and its downstream factors in MAPK pathway.
Conclusions
Our study revealed that circMAPK1 inhibits the malignant biological behavior of gastric cancer cells through its encoded protein MAPK1–109aa. More importantly, circMAPK1 is a favorable predictor for gastric cancer patients and may provide a new therapeutic target in the treatment of gastric cancer.
Journal Article
Circular RNA AKT3 upregulates PIK3R1 to enhance cisplatin resistance in gastric cancer via miR-198 suppression
2019
Background
Cisplatin (CDDP) treatment is one of the most predominant chemotherapeutic strategies for patients with gastric cancer (GC). A better understanding of the mechanisms of CDDP resistance can greatly improve therapeutic efficacy in patients with GC. Circular RNAs (circRNAs) are a class of noncoding RNAs whose functions are related to the pathogenesis of cancer, but, in CDDP resistance of GC remains unknown.
Methods
circAKT3 (hsa_circ_0000199, a circRNA originating from exons 8, 9, 10, and 11 of the AKT3 gene) was identified by RNA sequencing and verified by quantitative reverse transcription PCR. The role of circAKT3 in CDDP resistance in GC was assessed both in vitro and in vivo. Luciferase reporter assay, biotin-coupled RNA pull-down and fluorescence in situ hybridization (FISH) were conducted to evaluate the interaction between circAKT3 and miR-198. Functional experiments were measured by western blotting, a cytotoxicity assay, clonogenic assay and flow cytometry.
Results
The expression of circAKT3 was higher in CDDP-resistant GC tissues and cells than in CDDP-sensitive samples. The upregulation of circAKT3 in GC patients receiving CDDP therapy was significantly associated with aggressive characteristics and was an independent risk factor for disease-free survival (DFS). Our data indicated that circAKT3 promotes DNA damage repair and inhibits the apoptosis of GC cells in vivo and in vitro. Mechanistically, we verified that circAKT3 could promote PIK3R1 expression by sponging miR-198.
Conclusions
circAKT3 plays an important role in the resistance of GC to CDDP. Thus, our results highlight the potential of circAKT3 as a therapeutic target for GC patients receiving CDDP therapy.
Journal Article
Dielectronic recombination of W37+ and electron-impact ionization of W36
2022
Abstractab initio calculations of dielectronic recombination rate coefficient of W37+ forming W36+ and electron-impact ionization cross section of W36+ have been performed. Energy levels, radiative transition probabilities, autoionization rates, electron-impact excitation and ionization cross sections are calculated using the flexible atomic code (FAC). Good agreement between the present level-to-level distorted wave treatment and previous ADAS data is found for the dielectronic recombination rate coefficients of W37+ . Electron-impact direct ionization and excitation-autoionization contributions to the total single-ionization cross sections were calculated employing a level-to-level distorted-wave approximation. The calculation result shows that the total ionization cross section will be underestimated by 50% near ionization threshold to ∼ 8% at higher energy without include the contribution from excitation-autoionization process.Graphical abstract
Journal Article
Robot adoption and urban total factor productivity: evidence from China
2024
Industrial robots are having a profound and lasting impact on China’s economy. This research examines the deployment of industrial robots and their effects on urban total factor production from theoretical and empirical angles. It is created using panel data from 286 cities at the prefecture level between 2003 and 2017. It is found that: First, robot adoption promotes urban total factor productivity. Second, adopting robots has a more positive influence on urban total factor productivity development in western, underdeveloped, and less market-oriented areas compared to the developed and market-oriented areas in the east. Third, adopting robots could enhance urban innovation vitality, increase total factor productivity, boost industrial agglomeration, and improve technological progress or technical efficiency. Policy enlightenment provided by these findings can guide future technological advancements and promote high-quality city development.
First published online 07 June 2024
Journal Article
Oxygen-independent organic photosensitizer with ultralow-power NIR photoexcitation for tumor-specific photodynamic therapy
2024
Photodynamic therapy (PDT) is a promising cancer treatment but has limitations due to its dependence on oxygen and high-power-density photoexcitation. Here, we report polymer-based organic photosensitizers (PSs) through rational PS skeleton design and precise side-chain engineering to generate •O
2
−
and •OH under oxygen-free conditions using ultralow-power 808 nm photoexcitation for tumor-specific photodynamic ablation. The designed organic PS skeletons can generate electron-hole pairs to sensitize H
2
O into •O
2
−
and •OH under oxygen-free conditions with 808 nm photoexcitation, achieving NIR-photoexcited and oxygen-independent •O
2
−
and •OH production. Further, compared with commonly used alkyl side chains, glycol oligomer as the PS side chain mitigates electron-hole recombination and offers more H
2
O molecules around the electron-hole pairs generated from the hydrophobic PS skeletons, which can yield 4-fold stronger •O
2
−
and •OH production, thus allowing an ultralow-power photoexcitation to yield high PDT effect. Finally, the feasibility of developing activatable PSs for tumor-specific photodynamic therapy in female mice is further demonstrated under 808 nm irradiation with an ultralow-power of 15 mW cm
−2
. The study not only provides further insights into the PDT mechanism but also offers a general design guideline to develop an oxygen-independent organic PS using ultralow-power NIR photoexcitation for tumor-specific PDT.
Conventional photodynamic therapy (PDT) is hindered by oxygen-dependent photosensitization pathways and high-power-density photoexcitation. Here, the authors develop polymer-based organic photosensitizers (PSs) through PS skeleton design and side-chain engineering to allow tumor-specific PDT under oxygen-free conditions using ultralow-power 808 nm photoexcitation.
Journal Article
Chronic stress promotes gastric cancer progression and metastasis: an essential role for ADRB2
2019
An increasing number of studies indicate that adrenergic signalling plays a fundamental role in chronic stress-induced tumour progression and metastasis. However, its function in gastric cancer (GC) and its potential mechanisms remain unknown. The expression levels of β-adrenergic receptor (ADRB) in GC cell lines were examined by using real-time polymerase chain reaction (RT-PCR) and western blotting. The effects of β2 adrenergic receptor (ADRB2) activation and blockade were investigated in vitro in GC cells by using proliferation, migration, invasion, cell cycle and apoptosis assays. Chronic restraint stress (CRS) increased the plasma levels of catecholamines and cortisol and also induced progression and metastasis of GC in vivo. Furthermore, immunohistochemical staining and a TUNEL assay were employed to observe the regulation of cell viability in vivo. The expression levels of ADRB2 in 100 human GC samples were measured by RT-PCR and immunohistochemistry. The stress hormones epinephrine and norepinephrine significantly accelerated GC cell proliferation, invasion and viability in culture, as well as tumour growth in vivo. These effects were reversed by the ADRB antagonists propranolol and ICI118,551 (an ADRB2-specific antagonist). Moreover, the selective ADRB1 antagonist atenolol had almost no effect on tumour cell proliferation and invasion in vitro and in vivo. ADRB2 antagonists suppressed proliferation, invasion and metastasis by inhibiting the ERK1/2-JNK-MAPK pathway and transcription factors, such as NF-κB, AP-1, CREB and STAT3. Analysis of xenograft models using GC cells revealed that ADRB2 antagonists significantly inhibited tumour growth and metastasis, and chronic stress antagonized these inhibitory effects. In addition, chronic stress increased the expression of VEGF, MMP-2, MMP-7 and MMP-9 in transplanted tumour tissue, and catecholamine hormones enhanced the expression of metastasis-related proteins. The expression of ADRB2 was upregulated in tumour tissues and positively correlated with tumour size, histological grade, lymph node metastasis and clinical stage in human GC samples. Stress hormone-induced activation of the ADRB2 signalling pathway plays a crucial role in GC progression and metastasis. These findings indicate that ADRB2 signalling regulates GC progression and suggest β2 blockade as a novel strategy to complement existing therapies for GC.
Journal Article