[Interference of P2X4 receptor expression in tumor-associated macrophages suppresses migration and invasion of glioma cells]

OBJECTIVE

To investigate the effect of interference of P2X4 receptor expression in tumor-associated macrophages (TAMs) on invasion and migration of glioma cells.

METHODS

C57BL/6 mouse models bearing gliomas in the caudate nucleus were examined for glioma pathology with HE staining and expressions of Iba-1 and P2X4 receptor with immunofluorescence assay. RAW264.7 cells were induced into TAMs using conditioned medium from GL261 cells, and the changes in mRNA expressions of macrophage polarization-related markers and the mRNA and protein expressions of P2X4 receptor were detected with RT-qPCR and Western blotting. The effect of siRNA-mediated P2X4 interference on IL-1β and IL-18 mRNA and protein expressions in the TAMs was detected with RT-qPCR and Western blotting. GL261 cells were cultured in the conditioned medium from the transfected TAMs, and the invasion and migration abilities of the cells were assessed with Transwell invasion and migration experiment.

RESULTS

The glioma tissues from the tumor-bearing mice showed a significantly greater number of Iba-1-positive cells, where an obviously increased P2X4 receptor expression was detected (P=0.001), than the brain tissues of the control mice (P < 0.001). The M2 macrophage markers (Arg-1 and IL-10) and M1 macrophage markers (iNOS and TNF-α) were both significantly up-regulated in the TAMs derived from RAW264.7 cells (all P < 0.01), but the up-regulation of the M2 macrophage markers was more prominent; the expression levels of P2X4 receptor protein and mRNA were both increased in the TAMs (P < 0.05). Interference of P2X4 receptor expression significantly lowered the mRNA(P < 0.01)and protein (P < 0.01, P < 0.05)expression levels of IL-1β and IL-18 in the TAMs and obviously inhibited the ability of the TAMs to promote invasion and migration of the glioma cells (P < 0.05).

CONCLUSION

Interference of P2X4 receptor in the TAMs suppresses the migration and invasion of glioma cells possibly by lowering the expressions of IL-1β and IL-18.

A Chewing Gum Residue-Based Gel with Superior Mechanical Properties and Self-Healability for Flexible Wearable Sensor

Chewing gum residue is hard to decompose and easy to cause pollution, which is highly desirable to realize the recycling. In this paper, a chewing gum gel with enhanced mechanical properties and self-healing properties is prepared by using polyvinyl alcohol (PVA) as the backbone in chewing gum residue. The hydrogen bond and the borax ester bond are employed to construct reversible interaction to enhance the self-healing ability. The physical crosslinking is realized by further freeze-thaw treatment to improve its mechanical properties. The gel demonstrates high elongation at break of 610% and strength of 0.11 MPa, as well as excellent self-healing performance and recyclable property. In particular, the gel with a fast signal response is successfully applied as a wearable strain sensor to monitor different types of human motion. The gel as a sensor exhibits self-healing properties suggesting superior safety and stability, and displays wide linear sensitivity (the gauge factor is 0.417 and 0.170). The gel can be further served to explore temperature changes, implying the application in temperature monitoring. This study develops a novel approach for the recycle and reuse of chewing gum residue. The obtained gel may be a promising candidate for the fabrication of flexible wearable sensor. This article is protected by copyright. All rights reserved.

Recovery patterns of soil bacterial and fungal communities in Chinese boreal forests along a fire chronosequence

Wildfire has profound and pervasive consequences for forest ecosystems via directly altering soil physicochemical properties and modulating microbial community. In this study, we examined the changes in soil properties and microbial community composition and structure at different periods after highly severe wildfire events (44 plots, 113 samples) in the Chinese Great Khingan Mountains. We also separated charcoal from burnt soils to establish the relationship between microbial community structures in soils and charcoal. We found that wildfire only significantly altered bacterial and fungal β-diversity, but had no effect on microbial α-diversity across a 29-year chronosequence. The network analysis revealed that the complexity and connectivity of bacterial and fungal communities were significantly increased from 17 years after fire, compared with either unburnt soils or soils with recent fires (0-4 years after fire). Differential abundance analysis suggested that bacterial and fungal OTUs were enriched or depleted only during 0-4 years after fire compared with the unburnt soils. In addition, soil pH, dissolved organic C and dissolved organic N were key determinants of soil bacterial and fungal communities during 17-29 years after fire. The fire-derived charcoal provided a new niche for microbial colonization, and microbes colonized in the charcoal had a significantly different community structure from those of burnt soils. Our data suggest that soil bacterial and fungal communities changed significantly during the recovery from fire events in terms of the abundance and co-occurrence networks in the boreal forest ecosystems.

Influence of tetracycline on arsenic mobilization and biotransformation in flooded soils

This study examined the effect of tetracycline addition on arsenic (As) mobilization and biotransformation in two contrasting soils (upland soil and paddy soil) under flooded conditions. The soils with added tetracycline (0-50 mg kg^-1) were incubated for 30 days, and soil properties and microbial functional genes over time were quantified. Tetracycline significantly promoted As reduction and As release into porewater in both soils. The enhancement had resulted from an increase in the concentration of dissolved organic carbon and a decrease in soil redox potential. Tetracycline also increased the abundances of As-reducing genes (arsC and arrA) and the relative abundances of As-reducing bacteria Streptomyces, Bacillus, Burkholderia, Clostridium and Rhodococcus, all of which have been found resistant to tetracycline. These genera play a key part in stimulating As reduction in the presence of tetracycline. The study indicated the significance of tetracycline in the biochemical behavior of As in flooded soils and provided new insights into the potential effects of tetracycline on the quality and safety of agricultural products in the future.

[Emergency training need and effect evaluation analysis of novel coronavirus pneumonia in centers of disease control and prevention]

A questionnaire was used to investigate the emergency training needs of novel coronavirus pneumonia of disease prevention and control institutions in provinces, deputy provincial level regions and cities specifically designated in the state plan, and the effect evaluation of emergency training activities conducted by Chinese Center for Disease Control and Prevention (China CDC). The results showed that 67.4% of 47 disease prevention and control institutions (31/46) believed that the emergency training at the initial stage of the epidemic should be conducted as soon as possible, and the form of network training should be given priority. The training should focus on the urgently needed technologies such as epidemiological investigation, formulation and response of prevention and control strategies, laboratory testing, etc. The teaching materials should highlight pertinence and practicability and be presented in the form of electronic video. The average satisfaction score of the video training conducted by China CDC was (8.81±1.125) and the score of audio-video courseware was (8.97±0.893). The needs analysis and evaluation of novel coronavirus pneumonia prevention and control in disease prevention and control institutions could provide reference for the follow-up training and improve the emergency training management.

Novel agricultural waste-based materials decrease the uptake and accumulation of cadmium by rice (Oryza sativa L.) in contaminated paddy soils

Heavy metal pollution in paddy fields has caused widespread concerns due to the threat to food safety. The present study used low-cost sugarcane bagasse (SB) and two sugarcane bagasse materials modified with citric-acid (SSB) and citric-acid/Fe₃O₄ (MSB) to investigate their effects on the bioavailability of Cd in soil and Cd accumulations in rice in a pot experiment. The three organic amendments significantly decreased the Cd accumulation in plants by limiting its mobilization in soil. The MSB and SSB but not SB increased the soil pH and immobilized the Cd in soil significantly during the 120-day experiment. The amendments decreased Cd bioavailability through transforming to the stable fraction throughout the whole growth stage. The functional groups in the amendments (-OH, -COOH, C-O, -COO^- and Fe-O) and precipitates [Cd(NO₂)₂K(NO₂)₂, Cd(OH)₂ and Cd₇₅Zn₂₅Fe₂O₄] played active roles in Cd immobilization. Moreover, the three organic materials increased the content of Fe-Mn plaque on rice roots, which prevented its transport from soil to rice roots further. We also found that Fe competed with Cd for transporters and reduced potential Cd uptake and translocation in rice tissues. The addition of MSB and SB but not SSB inhibited the rice growth compared to the unamended control, indicating the potential of SSB in situ remediation. These results provide valuable information to use organic amendments for Cd passivation in soil and food safety.

Contrasting effects of carbon source recalcitrance on soil phosphorus availability and communities of phosphorus solubilizing microorganisms

Carbon (C) additions to soil interact through chemical and microbiological processes to cause changes in soil phosphorus (P) availability. However, the response of soil P transformations and relevant microbial communities to C additions having different degrees of recalcitrance remains uncertain. We studied the effects of glucose, hemicellulose and lignin addition on soil P availability, P transformation processes and relevant microbial activity and communities in a P-deficient flooded soil. Lignin significantly increased soil available P concentrations, which was attributed to chemical release of inorganic P and increased alkaline phosphatase activity. Glucose and hemicellulose additions stimulated microbial metabolism of C thereby enhancing microbial demand for P, with increased soil P availability especially in the early incubation period. Glucose or hemicellulose addition changed soil microbial diversity and community composition, leading to enhanced growth and interactions of P solubilizing microorganisms such as Desulfitobacterium, Bacillus and Desulfosporosinus. Our results infer the importance of pH alteration and competitive sorption between PO₄ and functional groups of recalcitrant C (e.g., lignin) with Fe/Al (hydr) oxides in regulating soil P availability. Further, the microbial response to labile C additions led to increased P availability in the P-deficient soil. This study provides important mechanistic information to guide microbially-regulated soil P management in agricultural ecosystems.

[Current situation and suggestions of public health personnel training in disease control and prevention institutions]

Under the background that the national health has become the national priority development strategy, it is essential to speed up public health ability among talents. Based on the consulting project of the Chinese Academy of Engineering, "Research on the training strategy of medical and health personnel in China", this paper analyzes the current situation and existing problems of public health personnel training in disease control and prevention institutions. Based on three stages of public health education, this paper puts forward that the public health personnel training should first solve the problem of public health personnel team construction and create programs on college education-post graduate education-continuing education. Through the personnel training system, different training modes are designed for other groups of people to improve the ability of public health personnel in an all-around way.

Effect of alkaline lignin on immobilization of cadmium and lead in soils and the associated mechanisms

Lignin is a low-cost and environmental-friendly material and could increase the solubility of phosphorus (P) in soils. Meanwhile, application of P compounds to soils decreases the bioavailability of heavy metals. However, there are few reports on whether lignin-induced P release immobilizes heavy metals in soil. This study investigated this possibility by adding alkaline lignin to forest, paddy and upland soils differing in pH and available P. The amendment of alkaline lignin increased soil P availability and enhanced the adsorption and decreased the desorption percentages of Cd in acid forest and paddy soils. The P released from the soil could immobilize Pb and Cd but the presence of Pb decreased the adsorption capacity of Cd on the acid soils. In comparison, the alkaline lignin decreased Cd adsorption and raised Cd desorption in the alkaline upland soil, due to the formation of soluble complex of hydrophilic organic matter with Cd. In addition, precipitation, complexion, and competition effect among Cd, P and lignin in different soils led to various P concentrations in the experiment. The study suggests that alkaline lignin was effective in Cd/Pb immobilization partly via enhanced P availability in acid soils, but was ineffective in Cd immobilization in alkaline soils.

[The Museum of Western Studies on Chinese Medicine:Chinese medicine in the western societies]

The historical artifacts displayed in the Museum of Western study on Chinese Medicine at Yunnan University of Chinese Medicine came from a variety of Chinese medical schools in America and European countries. They are in the memorial galleries for some well-known figures, such as George Soulié de Morant (Su Lie), Jacques-André Lavier (La Wei Ai), Felix Mann (Man Fu Li) and Manfred Porkert (Man Xi Bo), representing the development and status of respective Chinese medical schools in America and European countries. The displayed artifacts are nearly 3,000 photos, manuscripts, documents and more than 500 hours of audiovisual materials, including instruments for acupuncture and moxibustion, books, passports, letters and even supplies for their life. The displayed artifacts demonstrate the process and the access of people in the western societies to know, learn and take use of Chinese medicine.

Metagenomic insights into soil microbial communities involved in carbon cycling along an elevation climosequences

Diversity and community composition of soil microorganisms along the elevation climosequences have been widely studied, while the microbial metabolic potential, particularly in regard to carbon (C) cycling, remains unclear. Here, a metagenomic analysis of C related genes along five elevations ranging from 767 to 4190 m at Mount Kilimanjaro was analysed to evaluate the microbial organic C transformation capacities in various ecosystems. The highest gene abundances for decomposition of moderate mineralizable compounds, i.e. carbohydrate esters, chitin and pectin were found at the mid-elevations with hump-shaped pattern, where the genes for decompositions of recalcitrant C (i.e. lignin) and easily mineralizable C (i.e. starch) showed the opposite trend (i.e. U-shaped pattern), due to high soil pH and seasonality in both low and high elevations. Notably, the gene abundances for the decompositions of starch, carbohydrate esters, chitin and lignin had positive relationships with corresponding C compounds, indicating the consistent responses of microbial functional profiles and metabolites to elevation climosequences. Understanding of adaptation of microbial communities, potential function and metabolites to elevation climosequences and their influencing factors provided a new insight for the regulation of terrestrial C storage.

Copper stimulates neonicotinoid insecticide thiacloprid degradation by Ensifer adhaerens TMX-23

AIMS

Aims of this study are to elucidate the molecular mechanism of copper-improved thiacloprid (THI) degradation by Ensifer adhaerens TMX-23 and characterize copper resistance of this strain.

METHODS AND RESULTS

Resting cells of E. adhaerens TMX-23 were used to degrade THI, with formation of THI amide and 98·31% of 0·59 mmol l^-1 THI was degraded in 100 min. The addition of copper improved the degradation of THI and showed little inhibitory effects on the growth of E. adhaerens TMX-23. E. adhaerens TMX-23 degraded THI to THI amide by nitrile hydratases (NhcA and NhpA). QPCR analysis indicated that the expression of nhpA was up-regulated in the presence of copper. E. adhaerens TMX-23 nitrile hydratases were purified, and enzyme assay of NhpA exhibited the highest NHase activity toward THI. The addition of copper activated the activity of NhcA. Soil degradation experiment indicated that E. adhaerens TMX-23 could quickly eliminate THI residual in copper-added soil.

CONCLUSIONS

Copper improved THI degradation by E. adhaerens TMX-23 was attributed to the induced expression of nhpA and activated NhcA.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study broadens the investigation of regulatory mechanism of NHase expression and provided theoretical basis for using metal-resistant microbes to degrade pesticide in heavy metal co-contaminated environments.

[Survey on provincial disease prevention and control professionals' attitudes and cognition to public health physician standardized training in China]

Objective: To understand the attitudes and cognition of disease control and prevention professionals at provincial level on public health physician standardized training and provide evidence for the improvement of the standardized training and exploration of more effective training mode in China. Methods: By cluster sampling, 2 193 professionals at provincial centers for disease control and prevention (CDC) in 6 provinces, including Jiangsu and Guangdong, Shanxi and Hubei,Sichuan and Xinjiang were selected as the study subjects, the sample size was estimated to be 1 933 persons. Results: A total of 1 716 provincial-level CDC professionals were surveyed, the support rate to the standardized training was 70.7%(1 213/1 716). The level of support was negatively associated with the educational level of professionals and their specialty of public health and preventive medicine. Of 875 public health and preventive medicine professionals, 61.6%(318/516) of those with master's degree or above supported the standard training for public health physicians, which was lower than 73.1%(225/308) of those with bachelor's degree and 86.3%(44/51) of those with college degree or below. There were 14.9%(232/1 555) of the respondents suggested a two year training, and 60.4%(933/1 544) suggesting a field training mode. In terms of training content, 86.6%(1 355/1 564) suggesting "epidemiological survey and public health practice", and 76.7%(1 199/1 564) suggesting "basic theories and methodology". Conclusions: In general, the professionals of provincial CDC showed a relatively low interest in the standardized training for public health physicians and failed to reach a consensus. Besides, they were ill-informed about current training duration, method and content. Thas, the professionals at provincial CDC are suggested to be the key target-population whom should be mobilized during the training pilot period, especially the highly educated ones with relevant specialties of public health. It is suggested that public health physician standardized training should to be implemented in whole CDC system to reach full consensus based on its practical achievements and effects. It is also suggested to establish public health graduate medical education system in China.

Plant material and its biochar differ in their effects on nitrogen mineralization and nitrification in a subtropical forest soil

Natural wildfires have a great effect on soil N transformation in subtropical forest. The pyrogenic organic matter (PyOM) in forest soils is mainly derived from the plant material burnt during forest fires, which affects soil N composition, N mineralization and nitrification. This study examined the effects of typical fresh plant material (leaves and twigs of Castanopsis sclerophylla, representing litter) and its biochar (representing PyOM) on N mineralization and nitrification in a subtropical forest soil. The soils were incubated with the plant material (PM), its biochar (BC) and their combinations for 84 days. Both PM and BC considerably increased soil pH and dissolved organic C, whereas PM decreased NO₃^--N and dissolved organic N. The additions of PM alone, and its combinations with BC resulted in net N immobilization. The rates of net N mineralization rapidly increased in first 14 days and then became stable following the addition of PM to soil. Moreover, the additions of PM and BC increased the abundances of archaeal amoA and bacterial amoA, especially with PM. The abundance of bacterial amoA correlated positively with soil pH and dissolved organic C, while archaeal amoA showed the opposite. Biochar affected soil properties and N transformation more significantly in the presence of PM, highlighting the need for further research on the interactions of plant litter and its biochar.