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As a biological carrier, exosomes participate in the communication between various kinds of cells, and can mediate the interactive 'dialogue' between tumor cells and tumor-associated macrophages (TAMs). TAMs are the most abundant cell population in the tumor stroma and are an important part of the tumor immune microenvironment. Various stimulating factors in the tumor microenvironment influence the polarization of TAMs into multiple phenotypes, such as M1 and M2. It plays a dual role in tumor immunity by both promoting and inhibiting tumor growth. Exosome-encapsulated non-coding RNAs (ncRNAs) participate in the interactive 'dialogue' between exosome-mediated TAMs and tumor cells. Tumor-derived exosomal ncRNAs can promote macrophage polarization, whereas exosomal ncRNAs derived from TAMs can affect tumor proliferation, metastasis, angiogenesis, and chemotherapy resistance. The present review summarizes the dual effects of exosomal ncRNAs on tumor cells and TAMs, and discusses the application of exosomal ncRNAs as a potential diagnostic or prognostic marker and drug delivery system, to provide a new perspective and potential therapeutic drugs on targeting exosomes and macrophages in the treatment of tumors.

Background Pancreatic adenocarcinoma (PAAD) has a high rate of mortality. Unfortunately, it is difficult to diagnosis. This study aimed to develop a more in-depth understanding of the disease. Methods A total of 177 patients with PAAD were recruited from The Cancer Genome Atlas (TCGA) database. Microarray analysis was performed to identify differentially expressed genes (DEGs) in PAAD. The microarray data were adapted to the ingenuity pathway analysis (IPA) for annotation and visualization, followed by protein-protein interaction (PPI) network analysis. In vitro transwell migration assays were conducted to explore the molecular and functional characteristics of pancreatic adenocarcinoma cells (PANC-1) with stable low expression of G-protein signaling modulator 2 (GPSM2). Expression of GPSM2 and the associated hub genes were detected by reverse transcription-quantitative polymerase chain reaction (qPCR). Results The overexpression of GPSM2 was proved in PAAD, as compared with the healthy tissues, as well as its correlation with history of chronic pancreatitis, T stage, TNM stage and tumor grade. We described it as an independent prognostic factor and found that it could influence the infiltration of immune cells in the tumor microenvironment. Silencing of GPSM2 restrained the and migration of the cells. Microarray analysis identified 1,631 DEGs in PAAD cells. The PPI network analysis identified hub genes including CD44, ITGB1, ITGB5, ITGA2, ITGA5, AKT1, EGFR, NRAS and MAP2K1, and their relationship with GPSM2 was confirmed by qPCR. Conclusions GPSM2 is a novel prognostic factor and therapeutic target for PAAD. GPSM2 promoted the migration of pancreatic adenocarcinoma cells .Targeting GPSM2 and its downstream genes may prolong the survival time of patients with PAAD.

In recent years, the strategy for tumor therapy has changed from focusing on the direct killing effect of different types of therapeutic agents on cancer cells to the new mainstream of multi-mode and -pathway combined interventions in the microenvironment of the developing tumor. Flavonoids, with unique tricyclic structures, have diverse and extensive immunomodulatory and anti-cancer activities in the tumor microenvironment (TME). Tumor-associated macrophages (TAMs) are the most abundant immunosuppressive cells in the TME. The regulation of macrophages to fight cancer is a promising immunotherapeutic strategy. This study covers the most comprehensive cognition of flavonoids in regulating TAMs so far. Far more than a simple list of studies, we try to dig out evidence of crosstalk at the molecular level between flavonoids and TAMs from literature, in order to discuss the most relevant chemical structure and its possible relationship with the multimodal pharmacological activity, as well as systematically build a structure-activity relationship between flavonoids and TAMs. Additionally, we point out the advantages of the macro-control of flavonoids in the TME and discuss the potential clinical implications as well as areas for future research of flavonoids in regulating TAMs. These results will provide hopeful directions for the research of antitumor drugs, while providing new ideas for the pharmaceutical industry to develop more effective forms of flavonoids.

Structured porous carbon materials have been extensively applied for catalyst, sensor, adsorbent, energy storage materials and many others. However, the preparation of such carbon materials in a controllable way remains a significant challenge. In this work, 3D printing has been employed to prepare porous carbon structures with tailorable pore sizes. A starch/gelatin ink has been applied as carbon source with SiO2 monodispersed spheres as hard template. The process exhibits an excellent printing accuracy. Controllable meso and macro structures can be thereby obtained. The printed monolithic structures have been used as metal-free catalysts for the selective oxidation of benzyl alcohol, as an illustration. The monolithic and meso/macro-porous structure has a remarkable influence on the reaction rate. A high conversion with high benzaldehyde selectivity has been achieved. The 3D printing strategy provides us a simple, low cost and reliable way of fabricating carbon structures with designable meso/macro-pores, which is promising for many other applications beyond catalysis.

With the development in tumor immunology, people are gradually understanding the complexity and diversity of the tumor microenvironment immune status and its important effect on tumors. Tumor-associated macrophages (TAMs), an important part of the tumor immune microenvironment, have a double effect on tumor growth and metastasis. Many studies have focused on lung cancer, especially non-small cell lung cancer and other "hot tumors" with typical inflammatory characteristics. The polarization and infiltration of TAMs is an important mechanism in the occurrence and development of malignant tumors, such as lung cancer, and in the tumor immune microenvironment. Therapeutic drugs designed for these reasons are key to targeting TAMs in the treatment of lung cancer. A large number of reports have suggested that natural compounds have a strong potential of affecting immunity by targeting the polarization and infiltration of TAMs to improve the immune microenvironment of lung cancer and exert a natural antitumor effect. This paper discusses the infiltration and polarization effects of natural compounds on lung cancer TAMs, provides a detailed classification and systematic review of natural compounds, and summarizes the bias of different kinds of natural compounds by affecting their antitumor mechanism of TAMs, with the aim of providing new perspectives and potential therapeutic drugs for targeted macrophages in the treatment of lung cancer.

Tuberculosis, caused by the pathogen Mycobacterium tuberculosis, is a serious infectious disease worldwide. Multidrug-resistant TB (MDR-TB) remains a global problem, and the understanding of this resistance is incomplete. Studies suggested that DNA methylation promotes bacterial adaptability to antibiotic treatment, but the role of mycobacterial HsdM in drug susceptibility has not been explored. Here, we constructed an inactivated Mycobacterium bovis (BCG) strain, ΔhsdM. ΔhsdM shows growth advantages over wild-type BCG under isoniazid treatment and hypoxia-induced stress. Using high-precision PacBio single-molecule real-time sequencing to compare the ΔhsdM and BCG methylomes, we identified 219 methylated HsdM substrates. Bioinformatics analysis showed that most HsdM-modified genes were enriched in respiration- and energy-related pathways. qPCR showed that HsdM-modified genes directly affected their own transcription, indicating an altered redox regulation. The use of the latent Wayne model revealed that ΔhsdM had growth advantages over wild-type BCG and that HsdM regulated trcR mRNA levels, which may be crucial in regulating transition from latency to reactivation. We found that HsdM regulated corresponding transcription levels via gene methylation, thus, altering the mycobacterial redox status and decreasing the bacterial susceptibility to isoniazid, which is closely correlated with the redox status. Our results provide valuable insight into DNA methylation on drug susceptibility.

Polyphenol compounds are natural antioxidants, which are rich in anti-inflammatory and antioxidant components. They have a wide range of medicinal benefits that are believed to improve human health across various aspects; especially its anticancer effect has been gradually confirmed. The anticancer effect of polyphenols is mainly based on their strong antioxidant and immunomodulatory effects. The innate and adaptive immune responses as well as the development and maintenance of cells and tissues of the immune system are regulated by the NF-κB family of transcription factors. Dysregulation of NF-κB can lead to autoimmune diseases, chronic inflammation, and even cancer. Polyphenol compounds can exert antioxidant and immunomodulatory effects by targeting NF-κB, thus hindering the occurrence and development of tumors.Polyphenol compounds have unique advantages over conventional anticancer therapies such as chemotherapy because they have few side effects and do not cause toxicity to healthy cells. Additionally, they can attenuate the toxic effects of current anticancer therapies. Based on these characteristics, polyphenols have great potential in the prevention and treatment of cancer. This article systematically summarizes the mechanism of NF-κB in tumor genesis, progression, metastasis, angiogenesis, and drug resistance. In addition, we present the anticancer effect of polyphenol compounds by targeting NF-κB during the different stages of tumorigenesis.

Noroviruses are one of the main pathogens of acute gastroenteritis, causing frequent outbreaks worldwide every year that seriously affect human health. The GII.4 genotype causes most norovirus (NoV) infections and large-scale outbreaks. By contrast, the GI genotype is relatively rare. In this study, the whole genome sequence of a newly isolated ZD strain from a patient in Beijing, China, was sequenced and analyzed. The ZD strain genome consisted of 7,597 nucleotides and contained three open reading frames. Whole-genomic analysis indicated the strain was a GI.1 genotype, and no recombination site was detected in the genome. The histo-blood group antigen (HBGA)binding site associated with invasion of the GI genotype did not change, implying relatively conservative evolution. Phylogenetic analysis indicated the VP1 sequence of GI.1 strains could be divided into three clusters according to time of appearance: older (1968-2011), earlier (2011-2015), and new (2017-2018). Each cluster showed distinctive amino acid substitution characteristics, and the number of substitutions increased with time. The isolated ZD strain was in the new cluster. This study is the first to conduct a phylogenetic analysis of a GI genotype NoV isolated from Beijing. The results improve understanding of NoV diversity in China and can be a reference for further study of nondominant epidemic strains of NoVs as well as epidemic prevention and control.

Summary Bacterial antibiotic resistance, a global health threat, is caused by plasmid transfer or genetic mutations. Quinolones are important antibiotics, partially because they are fully synthetic and resistance genes are unlikely to exist in nature; nonetheless, quinolone resistance proteins have been identified. The mechanism by which plasmid‐borne quinolone resistance proteins promotes the selection of quinolone‐resistant mutants is unclear. Here, we show that QnrB increases the bacterial mutation rate. Transcriptomic and genome sequencing analyses showed that QnrB promoted gene abundance near the origin of replication (oriC). In addition, the QnrB expression level correlated with the replication origin to terminus (oriC/ter) ratio, indicating QnrB‐induced DNA replication stress. Our results also show that QnrB is a DnaA‐binding protein that may act as an activator of DNA replication initiation. Interaction of QnrB with DnaA promoted the formation of the DnaA‐oriC open complex, which leads to DNA replication over‐initiation. Our data indicate that plasmid‐borne QnrB increases bacterial mutation rates and that genetic changes can alleviate the fitness cost imposed by transmitted plasmids. Derivative mutations may impair antibiotic efficacy and threaten the value of antibiotic treatments. Enhanced understanding of how bacteria adapt to the antibiotic environment will lead to new therapeutic strategies for antibiotic‐resistant infections.

In China, the rapid development greatly promotes the national economic power and living standard but also inevitably brings a series of environmental problems. In order to resolve these problems fundamentally, Chinese scientists have been undertaking research in the area of green chemical engineering (GCE) for many years and achieved great progresses. In this paper, we reviewed the research progresses related to GCE in China and screened four typical topics related to the Chinese resources characteristics and environmental requirements, i.e. ionic liquids and their applications, biomass utilization and bio-based materials/products, green solvent-mediated extraction technologies, and cold plasmas for coal conversion. Afterwards, the perspectives and development tendencies of GCE were proposed, and the challenges which will be faced while developing available industrial technologies in China were mentioned.

Tumor-associated macrophages (TAMs) are important immune cells in the tumor microenvironment, and their invasion in tumors is closely related to poor prognosis. Although TAMs are recognized as therapeutic targets, their heterogeneity makes studying tumor mechanism and developing drugs targeting TAMs difficult. The study of TAMs heterogeneity can be used to analyze the mechanism of tumor progression and drug resistance, and may provide possible treatment strategies for cancer patients. Single-cell RNA sequencing (scRNA-seq) can reveal the RNA expression profile for each TAM to distinguish heterogeneity, thereby providing a more efficient detection method and more accurate information for TAM-related studies. In this review, by summarizing the research progress in macrophage heterogeneity and other aspects of scRNA-seq over the past five years, we introduced the development of scRNA-seq technology and its application status in solid tumors, analyzed the advantages and selections of scRNA-seq in TAMs, and summarized the detailed specific research fields. To explore the mechanism of tumor progression and drug intervention from single cell level will provide new perspective for personalized treatment strategies targeting macrophages.

The development of technology and economy caused the dramatic increasing of car ownership. Therefore, infrastructures such as freeways have been built extensively in order to give the priority for private car using. However, large number of motorcar using caused problems for sustainability in aspect of environment, economy and society worldwide. Singapore has 5.7 million people living in a total land area of 728.6km2 by 2020, which makes this city state one of the most populated and urbanized countries in the world. In order to balance the increasing motorcar-using demand and scarce land, innovative approaches have been set for sustainable land transit. This essay describes background, institutional and policy environment of sustainable land transport system in CBD area, Singapore as case study to give the evaluation of the system and suggestions.

A series of Co3O4/HZSM-5 catalysts with different Co3O4 loadings were prepared by incipient wetness impregnation followed by thermal calcination or dielectric barrier discharge (DBD) plasma decomposition. Their catalytic performances for the complete combustion of methane were evaluated from 300 to 700 °C. The plasma decomposed samples exhibit much higher catalytic activity than the calcined ones. Among all the samples tested, the plasma decomposed catalyst with 20 wt.% loading of Co3O4 possesses the highest catalytic activity with T10 (10% CH4 conversion) at 300 °C and T100 (complete conversion) at 550 °C. The excellent catalytic activity of the DBD plasma decomposed samples would attribute to well-dispersed Co3O4, enhanced low-temperature reducibility, high content of lattice oxygen and adsorbed oxygen species, as well as the low formation tendency of the intermediate of Co-formate.

The redispersion of metal particle on the catalyst support is closely related to the stable operation as well as the regeneration process of catalysts. Pt/γ-Al2O3 is an important catalytic system for several industrial processes. Sintering of metal particles is usually a big challenge for Pt/γ-Al2O3, and the redispersion strategies have been developed to reverse the sintering process. In this work, the redispersion of Pt on γ-Al2O3 surface was studied via molecular simulation based on the density functional theory (DFT). The redispersion process was divided into two steps, the evaporation of Pt atom from the Pt cluster and the capture of Pt species over the Al2O3 surface. The result shows that the addition of HCl during the redispersion is helpful to both of the processes. The oxychlorination can reduce the minimum temperature of the Pt evaporation and increase the maximum allowable temperature of the capture of Pt species, leading to a thermodynamically favored redispersion process. The result explained the mechanism of the redispersion behavior of Pt on the γ-Al2O3 support during oxychlorination for the Pt/γ-Al2O3 catalyst. The method can also be extended to the study on the redispersion of other catalytic systems.

Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catalyst preparation is necessary to prevent and eliminate waste from each step of the catalyst preparation. We summarize recent progress in the application of cold plasmas for green catalyst preparation. Cold plasma preparation can reduce the catalyst size, improve the dispersion and enhance catalyst-support interaction with the use of less or no hazardous chemicals. These improvements also lead to the enhancement of catalyst activity and stability. An alternative room temperature electron reduction with a non-hydrogen plasma as an electron source was developed for the reduction of noble metal ions in which no hazardous chemical reducing agent or hydrogen was needed. This creates many opportunities for the development of supported catalysts with heat sensitive substrates, including metal organic frameworks (MOFs), covalent organic framework (COFs), high surface area carbon, peptide, DNA, proteins and others. A novel floating metal catalyst on a water (or solution) surface has been established. Template removal using low temperature cold plasmas also leads to the formation of high surface area porous materials with characteristics that are normally only obtainable with high temperature calcination, but sintering can be avoided. Micro combustion has been developed for the removal of carbon template using cold plasma. This is promising for preparing many structured oxides in a simple way with no use of auxiliary chemicals. Many opportunities exist for the use of cold plasmas to make multi-metallic oxides. Some future development ideas are addressed.

Dielectric barrier discharge (DBD) plasma was applied for the decomposition of nickel nitrate under air at ∼150 °C. Calcination (at 500 °C) under air and hydrogen reduction (at 500 °C) thermally were then conducted. The obtained Ni/SiO 2 catalyst was investigated for steam reforming of methane (SRM) at the reaction temperatures of 600, 700 and 800 °C with a very low steam to methane molar ratio (H 2 O/CH 4 = 0.5), in order to test the coke resistance of the catalyst. The DBD plasma prepared catalyst possesses an average particle size of 5.5 nm, much smaller than 15.3 nm of the thermally calcined one. The smaller catalyst size can lead to an enhanced coke resistance over the plasma prepared catalyst. The carbon nanotubes obtained on the used plasma prepared catalyst are very different from those formed on the calcined catalyst. The plasma decomposition is excellent for further investigation of effect of the catalyst structure beyond the nickel catalyst.

The sluggish rate of the oxygen reduction reaction (ORR) in proton exchange membrane (PEM) fuel cells has been a major challenge. Significantly increasing efforts have been made worldwide towards a highly active ORR catalyst with high durability. Among all the catalysts exploited, Pt electrocatalysts are still the best in terms of a comprehensive evaluation. The investigation of Pt-based ORR catalysts is necessary for a practical ORR catalyst with low Pt content. This paper reviews recent progress in the studies of the mechanism, nanostructure, size effect and carbon supports of Pt electrocatalysts for the ORR. The importance of the size and structure control of Pt ORR catalysts, related with carbon support materials, is indicated. The potential methods for such control are discussed. The progress in theoretical studies and in situ catalyst characterization are also discussed. Finally, challenges and future developments are addressed.

Micro-combustion initiated by dielectric barrier discharge plasma has been applied for the removal of carbon template to prepare urchin-like ZnO particles. The combustion is operated at atmospheric pressure and low gas temperature (less than 150 °C), and the template is fully decomposed and rapidly removed. The obtained urchin-like ZnO possesses two distinct morphologies: nanosheets and sub-micro rods. The unique morphologies form on ZnO hexagonal nuclei with the template effect of activated carbon.

Three-dimensional (3D) printing, also known as additive manufacturing, is a fabrication method that has recently received worldwide attention. It provides a convenient and economical way to prepare 3D structures in designable ways. As the technology has developed and the operational costs have decreased, the applications of 3D printing have greatly expanded. Catalyst fabrication is a promising area for 3D printing. Printing processes result in better control of catalyst structures and catalyst distribution. In this perspective, a general overview of the commonly available 3D printing methods that are feasible for the preparation of heterogeneous catalysts is given. Additionally, recent works on printing strategies and new materials for catalysts are discussed. Future development is also addressed.

In this paper, we propose to predict the workloads of the service components within the composite workflow based on the communication of the queue condition of service nodes. With this information, we actively discard the requests that has high probability to be dropped in the later stages of the workflow. The benefit of our approach is the efficient saving of limited system resource as well as the SLA-satisfied system performance. We present mechanisms for four basic workflow patterns and evaluate our mechanism through simulation. The experiment results show that our mechanism can help to successfully serve more requests than the normal mechanism. In addition, our mechanism can maintain more stable response time than the normal one.

[This corrects the article DOI: 10.3389/fpubh.2024.1348426.]., (Copyright © 2024 Xintong, Tao, Shuying, Huq, Huiying and Michiko.)