MDSCs: Key Criminals of Tumor Pre-metastatic Niche Formation

The emergence of disseminated metastases remains the primary cause of mortality in cancer patients. Formation of the pre-metastatic niche (PMN), which precedes the establishment of tumor lesions, is critical for metastases. Bone marrow-derived myeloid cells (BMDCs) are indispensable for PMN formation. Myeloid-derived suppressor cells (MDSCs) are a population of immature myeloid cells that accumulate in patients with cancer and appear in the early PMN. The mechanisms by which MDSCs establish the pre-metastatic microenvironment in distant organs are largely unknown, although MDSCs play an essential role in metastasis. Here, we summarize the key factors associated with the recruitment and activation of MDSCs in the PMN and review the mechanisms by which MDSCs regulate PMN formation and evolution. Finally, we predict the potential value of MDSCs in PMN detection and therapy

Preliminary results of the Moon shadow using ARGO-YBJ detector

ARGO-YBJ is a "full coverage" air shower detector consisting of Resistive Plate Chambers(RPCs) at the Yangbajing High Altitude Cosmic Ray Laboratory (Tibet, China) at 4300 m a.s.l. (lat=30.11 • N, long=90.53 • E). Using the data collected with a carpet of RPCs(1900m 2 , about 1/3 of the whole ARGO-YBJ detector), the cosmic ray shadowing effect due to the Moon was studied. The 50% angular resolution is found to be ∼ 1.2 • with the Chess-board method and the Moon shadow with a significance of 4.9 σ is found displaced by 0.7 • westward and 0.5 • northward with respect to the expected position by the equi-zenith angle Method

Genetic diversity and molecular discrimination of wild tea plants from Yunnan Province based on inter-simple sequence repeats (ISSR) markers

To efficiently assess and discriminate wild tea germplasms, inter-simple sequence repeats (ISSR) were used to determine genetic relationships among 40 wild tea plants. A total of 275 bands were generated with 15 ISSR primers, of which 274 (99.6%) were polymorphic. The mean genetic similarity coefficient, the mean Nei’s gene diversity (h) and the mean Shannon’s information index (I) of tea cultivars were 0.4180, 0.3797 and 0.5586, respectively. This suggested that the genetic diversity of wild tea trees and the genetic base were very wide. Unweighted pair group method with arithmetic mean (UPGMA) cluster analysis showed clear genetic relationships among these germplasms, and the major clusters were related to known pedigree relationships. Besides, from the bands amplified, there were three independent ways to identify the tea varieties, such as unique ISSR markers, unique band patterns and a combination of the band patterns provided by different primers. Finally, the ISSR fingerprints of 40 tea germplasms were constructed by the combination of the band patterns. This research indicated that ISSR markers were very effective in differentiating the wild tea varieties, too.Keywords: Wild tea plants, inter-simple sequence repeats (ISSR), molecular discrimination, genetic diversit

Laboratory and Field Testing of an Automated Atmospheric Particle-Bound Reactive Oxygen Species Sampling-Analysis System

In this study, various laboratory and field tests were performed to develop an effective automated particle-bound ROS sampling-analysis system. The system uses 2′ 7′-dichlorofluorescin (DCFH) fluorescence method as a nonspecific, general indicator of the particle-bound ROS. A sharp-cut cyclone and a particle-into-liquid sampler (PILS) were used to collect PM2.5 atmospheric particles into slurry produced by a DCFH-HRP solution. The laboratory results show that the DCFH and H2O2 standard solutions could be kept at room temperature for at least three and eight days, respectively. The field test in Rochester, NY, shows that the average ROS concentration was 8.3 ± 2.2 nmol of equivalent H2O2 m−3 of air. The ROS concentrations were observed to be greater after foggy conditions. This study demonstrates the first practical automated sampling-analysis system to measure this ambient particle component

Structural characteristics and pyrolysis behavior of low-rank coal with different vitrinite/inertinite ratio

Pyrolysis is the basis of clean coal technologies such as coal liquefaction and gasification, especially for the low-rank coal. To further investigate the pyrolysis characteristics of low-rank coals, a series of different vitrinite/inertinite ratio ZJZ, MTH, and DT coals (V/I: 0.1, 0.76, and 1.76 respectively) are used as the research objects. The chemical structure of the sample was analyzed with Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction technology (XRD). The pyrolysis process and gas release behavior of coal samples at 30−900 °C was checked by TG-MS. The results show that the chemical structure content of low-rank coals with different V/I is quite different. Compared with the inertinite-rich ZJZ coals, the vitrinite-rich coals have relatively rich aliphatic structures, long aliphatic chains, and oxygen functional groups. Especially for DT coal, it has more C—O content. The corresponding aromatic structure content decreases with the increase of the mirror-inert ratio. With the increase of V/I in the coal, the aromatic layer spacing d002, the ratio of the aromatic layer size to the aromatic layer stacking height (La/Lc) increase, and Lc, La and the number of stacking layers (N) decrease. The weight loss ratio of DT, MTH, and ZJZ coal during pyrolysis is 36.4%, 32.2%, and 28.9% respectively. As the V/I decreases, the final pyrolysis gaseous product yield and the maximum pyrolysis rate decrease accordingly. During the pyrolysis process, the small molecular gas, such as H2, H2O, CH4, CO, CO2, are released; In addition, the content of released gas is closely related to the maceral composition. The mass of small molecules produced by inertinite-rich coal is almost lower than that produced by vitrinite-rich coal. Because the vitrinite in coal contains more aliphatic structures, and the polycondensation capacity between the aromatic layers is stronger, the free radicals fragment are easily formed during the thermal process and then combined into gas

The integrative analysis based on super-enhancer related genes for predicting different subtypes and prognosis of patient with lower-grade glioma

Objective: Emerging evidence revealed that super-enhancer plays a crucial role in the transcriptional reprogramming for many cancers. The purpose aimed to explored how the super-enhancer related genes affects the prognosis and tumor immune microenvironment (TIME) of patients with low-grade glioma (LGG).Methods: In this study, the differentially expressed genes (DEGs) between LGG cohorts and normal brain tissue cohort were identified by the comprehensive analysis of the super-enhancer (SE) related genes. Then non-negative matrix factorization was performed to seek the optimal classification based on the DEGs, while investigating prognostic and clinical differences between different subtypes. Subsequently, a prognostic related signature (SERS) was constructed for the comprehensive evaluation in term of individualized prognosis, clinical characteristics, cancer markers, genomic alterations, and immune microenvironment of patients with LGG.Results: Based on the expression profiles of 170 DEGs, we identified three SE subtypes, and the three subtypes showed significant differences in prognostic, clinicopathological features. Then, nine optimal SE-related genes were selected to construct the SERS through the least absolute shrinkage and selection operator Cox regression analysis. Survival analysis showed that SERS had strong and stable predictive ability for the prognosis of LGG patients in the The Cancer Genome Atlas, China Glioma Genome Atlas, and Remdrandt cohorts, respectively. We also found that SERS was highly correlated with clinicopathological features, tumor immune microenvironment, cancer hallmarks, and genomic alterations in LGG patients. In addition, the predictive power of SERS for immune checkpoint inhibitor treatment is also superior. The qRT-PCR results and immunohistochemical results also confirmed the difference in the expression of four key genes in normal cells and tumors, as well as in normal tissues and tumor tissues.Conclusion: The SERS could be suitable to utilize individualized prognosis prediction and immunotherapy options for LGG patients in clinical application

The combustion characteristics and kinetic analysis of low-rank coals with different vitrinite/inertinite ratio

To explain the effect of maceral composition on the combustion characteristics of coal, a series of low-rank coals with different vitrinite/inertinite ratio were collected as the research object, and the combustion characteristics, heat change process and gas escape behavior of the samples under air atmosphere were investigated using thermoanalytical methods (TG-MS-DTA). The results show that the maceral content has little effect on the temperature of the maximum reaction rate. However, it has an effect on the value of the maximum reaction rate, and the maximum reaction rate of the inertinite-rich coal is larger. Meanwhile, higher minerals in coal allow the reaction to reach its maximum rate at a higher temperature. The combustion process shows two obvious stages. The first stage (before 400 ℃) is exothermic slowly, corresponding to the devolatilization process, and the second stage (after 400 ℃) is exothermic rapidly, corresponding to the fixed-carbon combustion process. The exothermic characteristics of coal combustion show a slow to fast exothermic transition. Coal with different vitrinite/inertinite ratio mainly release CO2, CO, H2O during the combustion process, however, the relative content of the released gas is different. In the devolatilization stage, there is less CO2 and CO released, while more H2O release. In the fixed-carbon combustion stage, a large amount of CO2 is released, the amount of CO released is slightly lower, and H2O is the lowest. Among them, the inertinite-rich coal releases relatively more CO2 during the combustion process and burns more completely under the same conditions. In addition, the kinetic calculation of the coal combustion process is carried out with the Coats-Redfern method, and the trend of reaction activation energy increases as the vitrinite/inertinite ratio decreases. However, it does not affect the inertinite-rich coal in the fixed-carbon combustion stage. The ability to burn rapidly may be due to the cell lumen structure formed by a large number of fusinites, which enlarges the contact area between the surface of coal particles and O2, and the combustion reaction is sufficient

Research progress on preparation and physicochemical properties of coal-based graphene quantum dots

Graphene quantum dots (GQDs) have attracted great research interest due to their remarkable quantum confinement and edge effects. In addition to exhibiting stable photoluminescence, it also has many advantages such as low cytotoxicity, good solubility and chemical inertness, making it widely used in bioimaging, photocatalysts and sensors. The industrial development of GQDs has been seriously hampered by the expensive raw materials and tedious operation of traditional preparation methods. Coal and its derivatives not only possess the characteristics of low price and abundant reserves, but also show greater advantages than graphite, graphene, graphite oxide and other carbon materials in the preparation of GQDs due to its inherent internal disorder structure and small crystal domain. GQDs can be prepared by simply stripping the aromatic ring clusters inside the coal and its derivatives through physical, chemical or electrochemical methods. This review first summarizes the “top-down” synthesis method of coal-based graphene quantum dots (C-GQDs) and its pros and cons. Then the structural morphology, chemical composition, fluorescence properties of C-GQDs and their influencing factors are analyzed. Further, we describe the progress in applications of C-GQDs in fields such as sensors, bioimaging and energy Finally, the future development of C-GQDs is discussed from the perspectives of preparation methods, carbon source selection and research directions, and the following experimental schemes are proposed: (1) Experiment with H2O2 as oxidizer and thermally altered coals as carbon sources； (2) Experiments other than oxidation with sulfuric acid and nitric acid using superhigh organic sulfur coals as carbon sources； (3) Experiment on coal macerals as a carbon sources. In addition, the combination of experimentally derived basic data and computer simulation technology can solve the problems of current research such as single fluorescence color and low quantum yield. The goals of clean utilization of coal resources and green development of GQDs have been achieved