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In recent years, studies have shown that low-dose supplemental infrared (IR) irradiation exhibits systemic anti-inflammatory effects. The gut microbiota is increasingly recognized as a potential mediator of these effects due to its role in regulating host metabolism and inflammatory responses. To investigate the role of gut microbiota diversity and metabolite changes in the mechanism of light-emitting diodes (LED) infrared's anti-inflammatory action, we conducted IR irradiation on mice. Serum inflammatory cytokines were measured using ELISA, and fecal samples were subjected to metagenomic, untargeted, and targeted metabolomic analyses. Our results demonstrated a significant increase in the anti-inflammatory cytokine IL-10 in the IR group, accompanied by a declining trend in pro-inflammatory cytokines. Gut microbiome analysis revealed distinct alterations in composition and functional genes between the groups, including the enrichment of beneficial bacteria like various species of Parabacteroides and Akkermansia muciniphila in the IR group. Notably, the IR group exhibited enrichment in carbohydrate metabolism pathways and a reduction in DNA damage and repair pathways. Furthermore, targeted metabolomic analysis highlighted a notable increase in short-chain fatty acids (SCFAs), including butyric acid and isobutyric acid, which positively correlated with the abundance of several beneficial bacteria. These findings suggest a potential interplay between gut microbiota-derived SCFAs and the anti-inflammatory response. In conclusion, our study provides comprehensive insights into the changes in gut microbiota species and functions associated with IR irradiation. Moreover, we emphasize the significance of altered SCFAs levels in the IR group, which may contribute to the observed anti-inflammatory effects. Our findings contribute valuable evidence supporting the role of low-dose infrared light irradiation as an anti-inflammatory therapy., (© 2024 American Society for Photobiology.)

Introduction: Helicobacter pylori (H. pylori) infection has been associated with gastric carcinogenesis. However, the precise involvement of LRP8, the low-density lipoprotein receptor-related protein 8, in H. pylori pathogenesis and gastric cancer (GC) remains poorly understood., Objectives: To investigate the potential role of LRP8 in H. pylori infection and gastric carcinogenesis., Methods: Three-dimensional human-derived gastric organoids (hGO) and gastric cancer organoids (hGCO) were synthesized from the tissues obtained from human donors. In this work, multi-omics combined with in vivo and in vitro studies were conducted to investigate the potential involvement of LRP8 in H. pylori-induced GC., Results: We found that H. pylori infection significantly upregulated the expression of LRP8 in human GC tissues, cells, organoids, and mouse gastric mucous. In particular, LRP8 exhibited a distinct enrichment in cancer stem cells (CSC). Functionally, silencing of LRP8 affected the formation and proliferation of tumor spheroids, while increased expression of LRP8 was associated with increased proliferation and stemness of GC cells and organoids. Mechanistically, LRP8 promotes the binding of E-cadherin to β-catenin, thereby promoting nuclear translocation and transcriptional activity of β-catenin. Furthermore, LRP8 interacts with the cytotoxin-associated gene A (CagA) to form the CagA/LRP8/β-catenin complex. This complex further amplifies H. pylori-induced β-catenin nuclear translocation, leading to increased transcription of inflammatory factors and CSC markers. Clinical analysis demonstrated that abnormal overexpression of LRP8 is correlated with a poor prognosis and resistance to 5-Fluorouracil in patients with GC., Conclusion: Our findings provide valuable information on the molecular intricacies of H. pylori-induced gastric carcinogenesis, offering potential therapeutic targets and prognostic markers for GC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Production and hosting by Elsevier B.V.)

Bacterial interactions occurring on and around seeds are integral to plant fitness, health and productivity. Although seed- and plant-associated bacteria are sensitive to environmental stress, the effects of microgravity, as present during plant cultivation in space, on microbial assembly during seed germination are not clear. Here, we characterized the bacterial microbiome assembly process and mechanisms during seed germination of two wheat varieties under simulated microgravity by 16S rRNA gene amplicon sequencing and metabolome analysis. We found that the bacterial community diversity, and network complexity and stability were significantly decreased under simulated microgravity. In addition, the effects of simulated microgravity on the plant bacteriome of the two wheat varieties tended to be consistent in seedlings. At this stage, the relative abundance of Oxalobacteraceae, Paenibacillaceae, Xanthomonadaceae, Lachnospiraceae, Sphingomonadaceae and Ruminococcaceae decreased, while the relative abundance of Enterobacteriales increased under simulated microgravity. Analysis of predicted microbial function revealed that simulated microgravity exposure leads to lower sphingolipid signaling and calcium signaling pathways. We also found that simulated microgravity drove the strengthening of deterministic processes in microbial community assembly. Importantly, some specific metabolites exhibited significant changes under simulated microgravity, suggesting that bacteriome assembly is mediated, at least in part, by metabolites altered by microgravity. The data we present here moves us closer to a holistic understanding of the plant bacteriome under microgravity stress at plant emergence, and provides a theoretical basis for the precise utilization of microorganisms in microgravity to improve plant adaptation to the challenge of cultivation in space., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Understanding the structural and antibiotic resistance changes of microbial communities in space environments is critical for identifying potential pathogens that may pose health risks to astronauts and for preventing and controlling microbial contamination. The research to date on microbes under simulated space factors has primarily been carried out on single bacterial species under the individual effects of microgravity or low-dose radiation. However, microgravity (MG) and low-dose ionizing radiation (LDIR) coexist in the actual spacecraft environment, and microorganisms coexist as communities in the spacecraft environment. Thus, the microbial response to the real changes present during space habitation has not been adequately explored. To address this knowledge gap, we compared the dynamics of community composition and antibiotic resistance of synthetic bacterial communities under simulated microgravit, low-dose ionizing radiation, and the conditions combined, as it occurs in spacecraft. To ensure representative bacteria were selected, we co-cultured of 12 bacterial strains isolated from spacecraft cleanrooms. We found that the weakened competition between communities increased the possibility of species coexistence, community diversity, and homogeneity. The number of Bacilli increased significantly, while different species under the combined conditions showed various changes in abundance compared to those under the individual conditions. The resistance of the synthetic community to penicillins increased significantly under low doses of ionizing radiation but did not change significantly under simulated microgravity or the combined conditions. The results of functional predictions revealed that antibiotic biosynthesis and resistance increased dramatically in the community under space environmental stress, which confirmed the results of the drug sensitivity assays. Our results show that combined space environmental factors exert different effects on the microbial community structure and antibiotic resistance, which provides new insights into our understanding of the mechanisms of evolution of microorganisms in spacecraft, and is relevant to effective microbial pollution prevention and control strategies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Committee on Space Research (COSPAR). Published by Elsevier B.V. All rights reserved.)

Understanding the microbial communities and antibiotic resistance genes (ARGs) in spacecraft assembly cleanrooms is crucial for spacecraft microbial control and astronaut safety. However, there have been few reports of ARG profiles and their relationship with microbiomes in such environments. In the present study, we assessed the bacterial community and ARGs in the air dust and surface environments of a typical spacecraft assembly cleanroom. Our results show a significant difference in bacterial composition between surfaces and air dust, as they belong to two distinct ecostates. Bacillus and Acinetobacter were significantly enriched in the air samples. Bacterial community network analysis revealed lower topological parameters and robustness of bacterial networks in the air samples. We also observed different distribution patterns of some typical ARGs between surface and air dust samples. Notably, the ermB gene exhibited a relatively high copy number and was enriched in the surface environment, compared to that in the air. Overall, our study provides insight into the complex microbial community and the distribution and transfer of ARGs in spacecraft assembly cleanrooms, and offers important input for developing control strategies against ARGs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: Atrial fibrillation (AF) and heart failure (HF) often coexist. The treatment of AF in patients with HF has been challenging because of the ongoing debate about the merits of catheter ablation vs. drug therapy., Methods: The Cochrane Library, PubMed, and www.clinicaltrials.gov were searched until June 14, 2022. Inclusion criteria were catheter ablation compared with drug therapy in adults with AF and HF in randomized controlled trials (RCTs). Primary outcomes consisted of all-cause mortality, re-hospitalization, change in left ventricular ejection fraction (LVEF), and AF recurrence. Secondary outcomes referred to quality of life [QoL; measured by the Minnesota Living with Heart Failure Questionnaire (MLHFQ)], six-minute walk distance (6MWD), and adverse events. The PROSPERO registration ID was CRD42022344208., Findings: In total, nine RCTs with 2,100 patients met the inclusion criteria, with 1,062 for catheter ablation and 1,038 for medication. According to the meta-analysis, catheter ablation significantly reduced all-cause mortality compared with drug therapy [9.2% vs. 14.1%, OR: 0.62, (95% CI: 0.47-0.82), P  = 0.0007, I 2   = 0%], improved LVEF [MD: 5.65%, (95% CI: 3.32-7.98), P <  0.00001, I 2   = 86%], reduced AF recurrence [41.6% vs. 61.9%, OR: 0.23, (95% CI: 0.11-0.48), P <  0.0001, I 2   = 82%], decreased the MLHFQ score [MD: -6.38, (95% CI: -11.09 to -1.67), P  = 0.008, I 2  = 64%] and increased 6MWD [MD: 17.55, (95% CI: 15.77-19.33), P <  0.0001, I 2   = 37%]. Catheter ablation did not increase the re-hospitalization [30.4% vs. 35.5%, OR: 0.68, (95% CI: 0.42-1.10), P  = 0.12, I 2   = 73%] and adverse events [31.5% vs. 30.9%, OR: 1.06, (95% CI: 0.83-1.35), P  = 0.66, I 2   = 48%]., Interpretation: In AF patients with HF, catheter ablation improves exercise tolerance, QoL, and LVEF and significantly reduced all-cause mortality and AF recurrence. Although the differences were not statistically significant, the study found lower re-hospitalization and approximate adverse events with improved catheter ablation tendency., Prospero Registration Id: CRD42022344208., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Lin, Sun, Liu, Su, Liang, Ma, Zhu, Fu and Liu.)

Papillary thyroid cancer (PTC) is a common malignancy. MicroRNAs (miRNAs) may act as oncogenes or tumor suppressor genes. However, the role of miR-451a in PTC is not fully understood. Hence, the objective of the study was to research the effect and mechanism of miR-451a in PTC. Differentially expressed miRNAs between GSE113629 and GSE103996 databases were assessed by Venn diagram. miR-451a and its downstream target genes were assessed by RT-PCR and Western blot. The proliferation, invasion, and apoptosis were determined by CCK-8, EdU, transwell, and flow cytometry assays. Dual-luciferase reporter assay were used to evaluated the target of miR-451a. Xenografted tumors was used to explore the function of miR-451a in vivo. Pathological changes and related protein expression were measured by HE staining and immunohistochemistry. MiR-451a was downregulated in PTC tissues and blood, and low expression of miR-451a was related to short overall survival, serious lymph node metastasis and high TNM grade in PTC patients. Moreover, increase of miR-451a restrained the proliferation and invasion and accelerated the apoptosis. Furthermore, miR-451a repressed VEGF signaling pathway. Importantly, miR-451a was demonstrated to target DCBLD2 and AKT1. Overexpression of DCBLD2 and AKT1 could restore the effect of miR-451a on PTC cells. In addition, miR-451a reduced the growth of xenografted tumors in vivo. The data suggested that miR-451a attenuated the proliferation, invasion and promoted apoptosis in PTC cells via inhibiting DCBLD2 and AKT1., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Chinese Lunar Palace 1 (LP1) is a ground-based bio-regenerative life support system (BLSS) test bed integrating highly efficient plant cultivation, animal protein production, urine nitrogen recycling, and bioconversion of solid waste. To date, there has been no molecular method-based detailed investigation of the fungal community and mycotoxin potential in BLSS habitats. To ensure safe BLSS design for actual space missions, we analyzed the LP1 surface mycobiome and mycotoxin potential during the Lunar Palace 365 project through internal transcribed spacer region 1 (ITS1) amplicon sequencing and quantitative polymerase chain reaction (qPCR) with primers specific for idh, ver1, nor1, tri5, and ITS1., Results: The LP1 system exhibited significant differences in fungal community diversity compared to other confined habitats, with higher fungal alpha diversity and different community structures. Significant differences existed in the surface fungal communities of the LP1 habitat due to the presence of different occupant groups. However, there was no significant difference between fungal communities in the plant cabin with various occupants. Source tracker analysis shows that most of the surface fungi in LP1 originated from plants. Regardless of differences in occupants or location, there were no significant differences in mycotoxin gene copy number., Conclusions: Our study reveals that plants are the most crucial source of the surface fungal microbiome; however, occupant turnover can induce significant perturbations in the surface fungal community in a BLSS. Growing plants reduced fungal fluctuations, maintaining a healthy balance in the surface fungal microbiome and mycotoxin potential. Moreover, our study provides data important to (i) future risk considerations in crewed space missions with long-term residency, (ii) an optimized design and planning of a space mission that incorporates crew shifts and plant growth, and (iii) the expansion of our knowledge of indoor fungal communities with plant growth, which is essential to maintain safe working and living environments. Video Abstract., (© 2022. The Author(s).)

To improve nutrient utilization and pathogenic resistance of plants in space, it is crucial to understand the effects of microgravity on the plant root microbiome. However, the finer details of whether and how microgravity affects the root microbiome remain unclear. Here, we found that simulated microgravity elicits no significant changes in fungal community composition and diversity, whether rhizosphere or endophytic. However, simulated microgravity caused a significant change in the composition and diversity of endophytic bacteria of wheat seedlings, but not in rhizosphere bacteria. The alteration of endophytic bacterial communities demonstrates that wheat seedlings adopt strategies to recruit additional endophytic Enterobacteriaceae and increase the stability of the endophytic bacterial network to respond to the challenge of simulated microgravity. Furthermore, our results also suggest that the corresponding changes in endophytic bacteria under simulated microgravity are closely related to a significant decrease in metabolites of the host's carbon metabolism, flavonoid biosynthesis, benzoxazinoid biosynthesis, and tryptophan metabolism pathways. Our findings reveal details important to our understanding of the impact of gravity on the microbial community of plant seedlings and the theoretical basis for manipulation of microorganisms to ensure efficient plant production in space., (© 2022 Society for Applied Microbiology and John Wiley & Sons Ltd.)

The activation of some oncogenes promote cancer cell proliferation and growth, facilitate cancer progression and metastasis by induce DNA replication stress, even genome instability. Activation of the cyclic GMP-AMP synthase (cGAS) mediates classical DNA sensing, is involved in genome instability, and is linked to various tumor development or therapy. However, the function of cGAS in gastric cancer remains elusive. In this study, the TCGA database and retrospective immunohistochemical analyses revealed substantially high cGAS expression in gastric cancer tissues and cell lines. By employing cGAS high-expression gastric cancer cell lines, including AGS and MKN45, ectopic silencing of cGAS caused a significant reduction in the proliferation of the cells, tumor growth, and mass in xenograft mice. Mechanistically, database analysis predicted a possible involvement of cGAS in the DNA damage response (DDR), further data through cells revealed protein interactions of the cGAS and MRE11-RAD50-NBN (MRN) complex, which activated cell cycle checkpoints, even increased genome instability in gastric cancer cells, thereby contributing to gastric cancer progression and sensitivity to treatment with DNA damaging agents. Furthermore, the upregulation of cGAS significantly exacerbated the prognosis of gastric cancer patients while improving radiotherapeutic outcomes. Therefore, we concluded that cGAS is involved in gastric cancer progression by fueling genome instability, implying that intervening in the cGAS pathway could be a practicable therapeutic approach for gastric cancer., Competing Interests: The authors have declared that they have no conflict of interest., (© 2021 Liu et al.)

The long-term exposure to enclosed environments may lead to chronic stress in crewmembers and affect their physical and mental state. Salivary microbiome and biomarkers of immune function are increasingly used in human health research. The "Lunar Palace 365" project, which was a 370-day, multicrew, enclosed experiment carried out in a ground-based bioregenerative life support system platform named Lunar Palace 1 (LP1). We investigated the temporal dynamics of the salivary microbiota and cytokines in the third phase of the "Lunar Palace 365" experiment, including 1 month before entering LP1 and 1 month after leaving Lp1. Results reveal no regular temporal change pattern in these parameters (highly abundant phyla and genera) during the experiment. Although the crewmembers' oral microbiota temporally changed, it recovered quickly after the study subjects left the enclosed environment. The levels of IL-6, IL-10, and TNF-α in crewmembers' saliva decreased after leaving the normal environment for the enclosed environment, indicating that their oral inflammatory response level was reduced. There were significant individual differences in crewmembers' salivary microbiota, however, the shared living space reduced these differences. Moreover, air microbiota might have also played a significant role in reducing the individual differences. In summary, the enclosed environment did not result in persistent changes in human salivary microbiota and oral immunity. This study provides some insights for studying the effect of enclosed controlled environments on human immunity and microbiome. IMPORTANCE Long-term exposure to space environments may influence the human microbiome, the human immune system, and the intricate balance between the two, causing impaired immunity and increased disease susceptibility. It was previously believed that the main potential factors of long-term spaceflight on human health were microgravity and radiation. However, the effects of long-term enclosed environments on human health were unclear. Bioregenerative life support systems (BLSS) is a good experimental model for studying the effects of enclosed environments on human systemic microbiota and immune disorders. We monitored the microbiota and cytokines in the saliva of crewmembers before they entered BLSS, during their stay in BLSS, and after leaving BLSS. The results indicated long-term closed environment will not cause persistent changes in human salivary microbiota and immunity.

Background: Understanding the dynamics of airborne microbial communities and antibiotic resistance genes (ARGs) in space life support systems is important because potential pathogens and antibiotic resistance pose a health risk to crew that can lead to mission failure. There have been few reports on the distribution patterns of microbiomes and ARGs in space life support systems. In particular, there have been no detailed investigations of microbiomes and/or antibiotic resistance based on molecular methods in long-term confined bioregenerative life support systems (BLSSs). Therefore, in the present study, we collected air dust samples from two crew shifts, different areas, and different time points in the "Lunar Palace 365" experiment. We evaluated microbial diversity, species composition, functional potential, and antibiotic resistance by combining cultivation-independent analyses (amplicon, shot-gun sequencing, and qPCR)., Results: We found that the bacterial community diversity in the Lunar Palace1 (LP1) system was higher than that in a controlled environment but lower than that in an open environment. Personnel exchange led to significant differences in bacterial community diversity, and source tracking analysis revealed that most bacteria in the air derived from the cabin crew and plants, but no differences in microbial function or antibiotic resistance were observed. Thus, human presence had the strongest effect on the succession of microbial diversity in the BLSSs., Conclusions: Our results highlight that microbial diversity in BLSSs is heavily influenced by changes in crew and is unique from other open and controlled environments. Our findings can be used to help develop safe, enclosed BLSS that meet the requirements of human survival and habitation in outer space. In addition, our results can further enhance our understanding of the indoor air microbial community and effectively maintain a safe working and living environment, including plant growth., (© 2022. The Author(s).)

As the core food crop of a bioregenerative life support system (BLSS), wheat is susceptible to pathogen infection due to the lack of effective microbial communities in the confined and isolated environment. Therefore, a thorough understanding of the dynamic changes in wheat rhizosphere fungi is of great significance for improving wheat production and ensuring the stability of the BLSS. In the current study, we collected samples of rhizosphere fungi in the four growth stages of wheat grown in the "Lunar Palace 365" experiment. We employed bioinformatics methods to analyze the samples' species composition characteristics, community network characteristics, and FUNGuild function analysis. We found that the species composition of rhizosphere fungi in the wheat at the tillering stage changed greatly in the closed and isolated environment, while the species composition in the seedling, flowering, and mature stage were relatively stable. The results of the FUNGuild function analysis showed that the functions of rhizosphere fungi changed during wheat development. The rhizosphere fungal community was centered on Ascomycota, Mortierellomycota, and Chytridiomycota, and the community showed the characteristics of a "small world" arrangement. The stage of wheat seedlings is characterized by a greater abundance, diversity, and complexity of the network of interactions in the rhizosphere mycorrhiza community, while the tillering stage exhibited a greater clustering coefficient. Based on the changes in species composition, guild function regulation, and community structure differences of the wheat rhizosphere fungi in the BLSS, our study identified the critical fungal species during wheat development, providing a reference for ensuring the health and yield of plants in the BLSS system. KEY POINTS: • The diversity, composition, FUNguild, and network structure of rhizosphere fungi were analyzed. • Ascomycota, Mortierellomycota, and Chytridiomycota were the center of the rhizosphere fungal community network. • The effects of different wheat developmental stages on the community composition, function, and network structure of rhizosphere fungi were examined., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Although synthesized nanotherapeutics (NTs) are attractive for the oral treatment of colon diseases, their clinical translations are constrained by the unsatisfactory therapeutic outcomes, potential adverse effects, and high cost of mass production. Here, we report the development of tea leaf-derived natural NTs with desirable particle sizes (140.0 nm) and negative surface charge (-14.6 mV). These natural exosome-like NTs were found to contain large amounts of lipids, some functional proteins, and many bioactive small molecules. Specifically, galactose groups on the surface of NTs could mediate their specific internalization by macrophages via galactose receptor-mediated endocytosis. Moreover, these NTs were able to reduce the production of reactive oxygen species, inhibit the expression of pro-inflammatory cytokines, and increase the amount of anti-inflammatory IL-10 secreted by macrophages. Orally administered NTs could efficiently inhibit the inflammatory bowel responses, restore disrupted colonic barriers and enhance the diversity and overall abundance of gut microbiota, thereby preventing or alleviating inflammatory bowel disease and colitis-associated colon cancer. The present study brings new insights to the facile application of a versatile and robust natural nanoplatform for the prevention and treatment of colon diseases., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

To travel beyond the Earth and realize long-term survival in deep space, humans need to construct Bioregenerative Life Support System (BLSS), which reduces the requirement for supplies from the Earth by in situ regenerating oxygen, water and food needed by astronauts, and prevents pollution to extraterrestrial bodies by recycling waste. Since the 1960s, the USSR/Russia, the United States, Europe, Japan, and China carried out a number of studies with abundant achievements in BLSS systematic theories, plants/animals/microorganisms unit technologies, design/construction, and long-term operation/regulation. China's "Lunar Palace 365″ experiment realized Earth-based closed human survival for a year, with a material closure of >98%. However, a lot of research work is still needed to ultimately realize BLSS application in space, especially given the space experiment of BLSS never carried out, and the overall impact of space environment on BLSS unknown. Lunar exploration projects such as lunar village and lunar research station are successively proceeding. Therefore, future BLSS research will focus on lunar probe payload carrying experiments to study mechanisms of small uncrewed closed ecosystem in space and clarify the impact of space environmental conditions on the ecosystem, so as to correct the design and operation parameters of Earth-based BLSS. Such research will provide theoretical and technological support for BLSS application in crewed deep space exploration., (Copyright © 2021. Published by Elsevier B.V.)

The abundance and type of immune cells in the tumor microenvironment (TME) significantly influence immunotherapy and tumor progression. However, the role of immune cells in the TME of gastric cancer (GC) is poorly understood. We studied the correlations, proportion, and infiltration of immune and stromal cells in GC tumors. Data analyses showed a significant association of infiltration levels of specific immune cells with the pathological characteristics and clinical outcomes of GC. Furthermore, based on the difference in infiltration levels of immune and stromal cells, GC patients were divided into two categories, those with "immunologically hot" (hot) tumors and those with "immunologically cold" (cold) tumors. The assay for transposase-accessible chromatin using sequencing and RNA sequencing analyses revealed that the hot and cold tumors had altered epigenomic and transcriptional profiles. Claudin-3 (CLDN3) was found to have high expression in the cold tumors and negatively correlated with CD8 + T cells in GC. Overexpression of CLDN3 in GC cells inhibited the expression of MHC-I and CXCL9. Finally, the differentially expressed genes between hot and cold tumors were utilized to generate a prognostic model, which predicted the overall survival of GC as well as patients with immunotherapy. Overall, we undertook a comprehensive analysis of the immune cell infiltration pattern in GC and provided an accurate model for predicting the prognosis of GC patients., (© 2021 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Wheat is the core food crop in bioregenerative life support systems (BLSSs). In confined isolation environments, wheat growth suffers from a lack of stable microbial communities and is susceptible to pathogenic infections due to the culture substrate's limitations. To overcome this limitation, the time series changes of wheat rhizosphere microorganisms in wheat production must be understood. In the present study, we examined the rhizosphere microbial samples from wheat at four different growth stages from plants collected from a BLSS plant cabin. We employed bioinformatics analysis strategies to analyze the characteristics of species composition, function prediction, and community network. The species composition of wheat rhizosphere microorganisms was relatively stable in the seedling, tillering, and flowering stages in confined isolation environments. However, we observed marked microbial changes at mature stages. The results of functional prediction analysis suggest that the rhizosphere microbial community function of "Energy metabolism" gradually decreased, and the function of "Transmembrane transport" gradually increased during wheat development. The construction of the rhizosphere microbial community is non-random, scale-free and has the characteristics of a small world. We found the tillering stage to be more complex than the other stages. Our study reveals the composition characteristics, functional changes, and community structure fluctuations of rhizosphere bacteria at different development stages of wheat in the isolated and controlled environment, providing a theoretical basis for the efficient production of BLSS plant systems. KEY POINTS: • We collected wheat rhizosphere microorganisms at different stages in a confined isolation environment. • The diversity, composition, function, and network structure of rhizosphere bacteria were analyzed. • The effect of different wheat stages on the composition, function, and network structure of rhizosphere microorganisms was speculated.

The general public spends one-third of its time under artificial lighting, which lacks bands beneficial to human health, and long-term exposure will have a negative impact on bone health. Here, we report the effects of long-term, low-dose ultraviolet (UV) supplementation to white light-emitting diode (LED) light exposure on intestinal microorganisms and bone metabolism, as well as the correlations between the two. Normal and ovariectomized rats were irradiated with LED white light with or without supplementation with UV. The effects of UV supplementation on the intestinal flora and the relationship between the intestinal flora and bone were investigated by measuring the intestinal flora, bone metabolism markers, and bone histomorphology. UV supplementation affected the bone density and bone mass by changing the relative content of Firmicutes, Saccharibacteria, and Proteobacteria; however, the intestinal flora were not the only factors affecting bone. Ultraviolet supplementation changed the composition and function of the gut flora in the bone loss model. By increasing the synthesis of short-chain fatty acids and affecting immunomodulatory, intestinal flora directly or indirectly regulate the activity of osteoclasts and thus mediate UV-mediated improvements in bone metabolism. Our work shows that UV supplementation affects bone density by influencing the intestinal flora, introducing a novel strategy to develop healthier artificial light sources and prevent bone loss. KEY POINTS: • We measured the bone metabolism markers and bone histomorphometry of rats. • The diversity, composition, and function of intestinal flora were analyzed. • The relationship between gut microbiota and host bone physiology was analyzed.

Adequate sunlight exposure helps reduce bone loss and is important to bone health. Currently, about 90% of the world population spends a major portion of daily life under artificial lighting. Unlike sunlight, LED white light, the main source of artificial lighting, has no infrared radiation, which is known to be beneficial to human health. In artificial lighting environments, infrared supplementation may be used to simulate the effects of sunlight on bone metabolism. Here, we supplemented white LED exposure with infrared light in normal and ovariectomized rats for three consecutive months and examined bone turnover, bone mass, and bone density. We also analyzed the structure and function of gut microbiota in the rats. Infrared supplementation significantly reduced the abundance of Saccharibacteria and increased the abundance of Clostridiaceae 1 and Erysipelotrichaceae bacteria. Our results indicate that changes in the gut microbiome correlate well with bone mass and bone metabolism. Our work demonstrates that infrared supplementation can have a positive effect on rat bone metabolism by affecting gut microbiota. Our findings will be important considerations in the future design of healthy lighting environments that prevent or possibly ameliorate osteoporosis., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Wheat seedlings are significantly impacted by the presence of bacteria. However, bacteria are unavoidably growing together with wheat. The study aimed to reveal wheat photosynthesis, phyllosphere bacterial community composition, and a shift in the bacterial community following different density treatments in a closed artificial ecosystem. Here, we report the relationship between photosynthesis and bacterial community in wheat seedlings for different planting densities. In this closed artificial ecosystem, a total of 30 phyla were detected, with 17 of them were simultaneously present in four treatments, under high light intensity and carbon dioxide growth environment. The key phyla detected include Firmicutes, Proteobacteria, and Bacteroidetes. We found that planting densities significantly impacted the photosynthetic characteristics of wheat and bacterial genetic biodiversity, but not on species composition of the bacterial community. Network analysis shows that the phyllosphere bacteria network structures were characterized by the clustering coefficient and modularity. Network for the 1000 plants/m 2 treatment group exhibits the highest levels of average clustering coefficient but lowest modularity and number of modules, among all plant densities tested. In addition, the network for the 1200 plants/m 2 treatment group exhibits the best characteristics in terms of net photosynthesis rate and intrinsic water use efficiency, higher complex phyllosphere community network structures, higher abundance of Corynebacterium, and more function of "Amino acid metabolism", which encourages the plants to grow better. The findings presented in this work elucidated the role of plant density in the growth of phyllosphere bacteria during wheat seedlings and provided theoretical support for reasonable wheat density cultivation in closed artificial ecosystems and wheat field production.

The growth of plants under high carbon dioxide (CO 2 ) concentrations (≥ 1000 ppm) is explored for the climate change and the bioregenerative life support system (BLSS) environment of long-duration space missions. Wheat (Triticum aestivum L.) is a grass cultivated for cereal grain-a global staple food including astronauts. Light and CO 2 are both indispensable conditions for wheat seedlings. This study provides insights on the physiology, antioxidant capacity and photosynthetic characteristics of wheat seedlings under a range of photosynthetic photon flux densities in a closed system simulating BLSS with high CO 2 concentration. We found that the F v /F m , F v /F 0 , chlorophyll content, intrinsic water use efficiencies (WUE i ), membrane stability index (MSI), and malondialdehyde (MDA) of wheat seedlings grown under an intermediate light intensity of 600 μmol m -2  s -1 environment were all largest. Interestingly, the high light intensity of 1200 mol m -2  s -1 treatment group exhibits the highest net photosynthetic rate but the lowest MDA content. The stomatal conductance and F 0 of high light intensity of 1000 μmol m -2  s -1 treatment group were both significantly higher than that of other groups. Our study provides basic knowledge on the wheat growth in different environments, especially in a closed ecosystem with artificial lights.

Since the discovery of metal nanoparticles (NPs) in the 1960s, unknown toxicity, cost and the ethical hurdles of research in humans have hindered the translation of these NPs to clinical use. In this work, we demonstrate that Pt NPs with protein coronas are generated in vivo in human blood when a patient is treated with cisplatin. These self-assembled Pt NPs form rapidly, accumulate in tumors, and remain in the body for an extended period of time. Additionally, the Pt NPs are safe for use in humans and can act as anti-cancer agents to inhibit chemotherapy-resistant tumor growth by consuming intracellular glutathione and activating apoptosis. The tumor inhibitory activity is greatly amplified when the Pt NPs are loaded in vitro with the chemotherapeutic drug, daunorubicin, and the formulation is effective even in daunorubicin-resistant models. These in vivo-generated metal NPs represent a biocompatible drug delivery platform for chemotherapy resistant tumor treatment.

Background: Asprosin has been identified as a novel hormone enriched in white adipose tissue and is pathologically increased in insulin-resistant mice and humans. However, information regarding the role of asprosin in type 2 diabetes mellitus (T2DM) remains unavailable. Via conducting a hospital-based study, we purposed to ascertain the potential relationship between circulating asprosin concentrations and T2DM., Methods: The study recruited 84 adults with T2DM and 86 controls with normal glucose tolerance. They matched in age, body mass index (BMI), and sex. Serum asprosin concentrations were measured via ELISA method., Results: Compared to the controls, serum asprosin concentrations were significantly increased in the T2DM adults (P<0.001). As asprosin concentrations increased across its tertiles, the percentage of T2DM increased (39.28, 37.50, and 70.68%; P value for trend <0.001). Multivariate logistic regression models demonstrated that compared with the 1st tertile of asprosin, the odds ratio of T2DM was 3.278(95% CI 1.053-10.200, P=0.040) for the 3rd tertile after adjustment for potential confounders. Area under ROC curve of asprosin (sex and age adjusted) for predicting the presence of T2DM was 0.707[95% CI 0.628-0.786]. Finally, multiple stepwise regression analysis indicated that fasting glucose and triglyceride were independently associated with serum asprosin in T2DM., Conclusions: Asprosin concentrations are increased in adults with T2DM. The results suggest that asprosin might serve as a risk factor associated with the pathogenesis of T2DM, but not an ideal biomarker for predicting T2DM., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Bioregenerative life support systems (BLSS) provide self-sufficient food ingredients to support long-term manned missions. It is crucial to transform raw food ingredients that are regenerated in situ in BLSS into nutritional and delectable meals for spacecraft crews. It is in our interest to develop a dietary menu with Chinese characteristics that comprises biomass produced in situ with BLSS regenerated ingredients., Results: Here we report an optimized Chinese 4-day diet meal plan for 'Lunar Palace 1' that is nutritionally balanced and highly acceptable. The 2900 cal diet menu not only meets the requirements of a balanced diet for crews but also exceeds the recommended levels for most nutrients. Specifically, daily fresh food consumption in our meal plan is 1267 g day -1 , of which 78% is provided by crops and insects regenerated in situ in the BLSS. The meal plan is highly favored by Chinese crews, with acceptability as high as 7.8-8.2 on a 9-point hedonic scale. We further confirmed that our meal plan satisfies crews' basic nutritional needs through a 105-day closed habitation experiment., Conclusion: In brief, the findings provide new insights for dietary meal plan design in future long-term manned missions. © 2018 Society of Chemical Industry., (© 2018 Society of Chemical Industry.)

Working and living under artificial lighting environment for a long duration do not allow sufficient sunlight exposure, resulting in an adverse effect on bone. Common artificial light source, white LED light, does not include ultraviolet irradiation that plays an important role in bone metabolism. Ultraviolet supplementation in artificial lighting environment can be used to simulate the effect of sunlight irradiation on bone metabolism. In this paper, we report the effects of long-term exposure of low-dose ultraviolet irradiation on the rats' bones and skin. We studied the changes in body weight, bone metabolism markers, bone mass content, bone mineral density, and skin of rats, under long-term exposure of low-dose ultraviolet irradiation. We found that the rats exposed to ultraviolet irradiation showed an increase in bone formation rate, decrease in bone resorption rate, and improvement in bone mass content and bone mineral density without adverse effects on skins. This paper provides an effective basis for future application of LED light to create a healthier, safer, and more comfortable indoor lighting environment., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Understanding the dynamics of human gut microbiota in space is crucial in maintaining astronaut health. Long-duration and deep-space manned exploration will require the in situ regeneration of resources, which would be achieved by an artificial ecosystem, such as a bioregenerative life-support system (BLSS). Potential response of human gut microbiota to particular lifestyle and dietary structure experienced in a BLSS remains unclear. Here, we report how a BLSS impacts the gut microbiota during a 105-day study that took place in the Chinese Lunar Palace 1 (LP1). The three crewmembers were provided with high-plant and high-fibre diet, and they followed a fixed schedule including extensive labour in the plant cabin. The gut microbiota composition of the three crewmembers showed convergence and similar dynamic change. Increased diversity and abundance of Lachnospira, Faecalibacterium and Blautia indicated that the LP1 dietary structure and the lifestyle may be beneficial for the maintenance of healthy gut microbiome. A stronger impact was found from the gut microbiome to the environment compared with the opposite direction, suggesting the necessity of environmental pathogen control in BLSS., (© 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.)

Aims: C1q/TNF-related protein 9 (CTRP9) is an adipokine mainly secreted by white adipose tissue and plays protective roles in energy metabolism. However, information regarding the role of CTRP9 in nonalcoholic fatty liver disease (NAFLD) is scarce. Here we aimed to ascertain the clinical relevance between circulating CTRP9 levels and NAFLD through a cross-sectional study., Methods: The study enrolled 82 NAFLD adults and 79 sex- and age-matched non-NAFLD controls. Serum CTRP9 was measured via ELISA method. Metabolic parameters were also determined., Results: Although serum CTRP9 level seems to be higher in NAFLD adults, there was no significant difference among the ultrasonographic degrees of NAFLD (P = 0.275). Further, after adjustment for BMI in the multinomial logistic regression model, no significant odds ratio difference was observed for NAFLD among the CTRP9 tertiles. Moreover, binary logistic regression models demonstrated that, body mass index (BMI) and alanine aminotransferase (ALT) but not CTRP9 were independent factors related to NAFLD. Besides, serum CTRP9 was positively correlated with BMI, waist circumference, Fasting insulin, HbA1c, and HOMA-IR in all subjects. BMI was the independent factor associated with serum CTRP9., Conclusions: Serum CTRP9 is not independently related to NAFLD. The association between serum CTRP9 and NAFLD might be due to the influence of obesity., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

There is much uncertainty about the risks of seed germination after repeated or protracted environmental low-dose ionizing radiation exposure. The purpose of this study is to explore the influence mechanism of low-dose ionizing radiation on wheat seed germination using a model linking physiological characteristics and developmental-dynamics simulation. A low-dose ionizing radiation environment simulator was built to investigate wheat (Triticum aestivum L.) seeds germination process and then a kinetic model expressing the relationship between wheat seed germination dynamics and low-dose ionizing radiation intensity variations was developed by experimental data, plant physiology, relevant hypotheses and system dynamics, and sufficiently validated and accredited by computer simulation. Germination percentages were showing no differences in response to different dose rates. However, root and shoot lengths were reduced significantly. Plasma governing equations were set up and the finite element analysis demonstrated H 2 O, CO 2 , O 2 as well as the seed physiological responses to the low-dose ionizing radiation. The kinetic model was highly valid, and simultaneously the related influence mechanism of low-dose ionizing radiation on wheat seed germination proposed in the modeling process was also adequately verified. Collectively these data demonstrate that low-dose ionizing radiation has an important effect on absorbing water, consuming O 2 and releasing CO 2 , which means the risk for embryo and endosperm development was higher., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Bioregenerative life-support systems (BLSS) address interactions between organisms and their environment as an integrated system through the study of factors that regulate the pools and fluxes of materials and energy through ecological systems. As a simple model, using BLSS is very important in the investigation of element cycling and energy flux for sustainable development on Earth. A 105-day experiment with a high degree of closure was carried out in this system from February to May, 2014, with three volunteers. The results indicate that 247 g·d -1 carbon was imported into the system from stored food. Most hydrogen is circulated as water, and more than 99% H 2 O can be lost through leaf transpiration into the atmosphere. A total of 1.8 g·d -1 "unknown oxygen" emerged between the input and output of the plant growth module. For the urine processing module, 20.5% nitrogen was reused and 5.35 g·d -1 was put into the nutrient solution. Key Words: Bioregenerative life-support systems (BLSS)-Lunar Palace-1-Artificial ecosystem-Element cycling-Energy flux. Astrobiology 17, 78-86.

To conduct crewed simulation experiments of bioregenerative life support systems on the ground is a critical step for human life support in deep-space exploration. An artificial closed ecosystem named Lunar Palace 1 was built through integrating efficient higher plant cultivation, animal protein production, urine nitrogen recycling, and bioconversion of solid waste. Subsequently, a 105-day, multicrew, closed integrative bioregenerative life support systems experiment in Lunar Palace 1 was carried out from February through May 2014. The results show that environmental conditions as well as the gas balance between O 2 and CO 2 in the system were well maintained during the 105-day experiment. A total of 21 plant species in this system kept a harmonious coexistent relationship, and 20.5% nitrogen recovery from urine, 41% solid waste degradation, and a small amount of insect in situ production were achieved. During the 105-day experiment, oxygen and water were recycled, and 55% of the food was regenerated. Key Words: Bioregenerative life support systems (BLSS)-Space agriculture-Space life support-Waste recycle-Water recycle. Astrobiology 16, 925-936.

The microbial communities of plant ecosystems are in relation to plant growing environment, but the alteration in biodiversity of rhizosphere and phyllosphere microbial communities in closed and controlled environments is unknown. The purpose of this study is to analyze the change regularity of microbial communities with wheat plants dependent-cultivated in a closed artificial ecosystem. The microbial community structures in closed-environment treatment plants were investigated by a culture-dependent approach, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), and Illumina Miseq high-throughput sequencing. The results indicated that the number of microbes decreased along with time, and the magnitude of bacteria, fungi, and actinomycetes were 10(7)-10(8), 10(5), and 10(3)-10(4) CFU/g (dry weight), respectively. The analysis of PCR-DGGE and Illumina Miseq revealed that the wheat leaf surface and near-root substrate had different microbial communities at different periods of wheat ecosystem development and showed that the relative highest diversity of microbial communities appeared at late and middle periods of the plant ecosystem, respectively. The results also indicated that the wheat leaf and substrate had different microbial community compositions, and the wheat substrate had higher richness of microbial community than the leaf. Flavobacterium, Pseudomonas, Paenibacillus, Enterobacter, Penicillium, Rhodotorula, Acremonium, and Alternaria were dominant in the wheat leaf samples, and Pedobacter, Flavobacterium, Halomonas, Marinobacter, Salinimicrobium, Lysobacter, Pseudomonas, Halobacillus, Xanthomonas, Acremonium, Monographella, and Penicillium were dominant populations in the wheat near-root substrate samples.

Porous-tube nutrient delivery system (PTNDS) allows high control of the root environment and prevents plant infections in both microgravity and ground conditions. In this paper, six soybean cultivars ('ZH13', 'ZH57', 'LD10', 'HH35', 'HH43', and 'ZGDD') were evaluated in terms of yield, photosynthetic efficiency, insoluble dietary fiber and ions uptake efficiency. Besides proximal composition, the concentrations of mineral and isoflavones were monitored in the seeds. 'HH35' and 'ZH13' plants showed much higher yield and harvest index, in addition to the lower lignin content of inedible biomass. Data showed that 'HH35' had the higher photosynthetic efficiency of soybean leaves with regard to photosynthetic rate and instantaneous carboxylation efficiency, whereas chlorophyll ratio and carotenoids content were no difference with the other cultivars. Both cations and anions except NH4(+) and H2PO4(-), were accumulated excessively compared to controls, especially with anions in PTNDS., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

It remains a mystery why the growth rate of bacteria is higher in low-dose ionizing radiation (LDIR) environment than that in normal environment. In this study, a hypothesis composed of environmental selection and competitive exclusion was firstly proposed from observed phenomena, experimental data and microbial ecology. Then a LDIR environment simulator (LDIRES) was built to cultivate a model organism of bacteria, Escherichia coli (E. coli) DH5α, the accurate response of bacterial population to ionizing radiation intensity variation was measured experimentally, and then the precise relative dosage of ionizing radiation E. coli DH5α population received was calculated by finite element analysis based on drift-diffusion equations of plasma. Finally, a highly valid mathematical model expressing the relationship between E. coli DH5α population and LDIR intensity was developed by system dynamics based on hypotheses, experimental data and microbial ecology. Both experiment and simulation results clearly showed that the E. coli DH5α individuals with greater specific growth rate and lower substrate consumption coefficient would adapt and survive in LDIR environment and those without such adaptability were finally eliminated under the combined effects of ionizing radiation selection and competitive exclusion., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Although terrestrial CO2 concentrations [CO2] are not expected to reach 1000 μmol mol(-1) (or ppm) for many decades, CO2 levels in closed systems such as growth chambers and greenhouses can easily exceed this concentration. CO2 levels in life support systems (LSS) in space can exceed 10,000 ppm (1 %). In order to understand how photosynthesis in C4 plants may respond to elevated CO2, it is necessary to determine if leaves of closed artificial ecosystem grown plants have a fully developed C4 photosynthetic apparatus, and whether or not photosynthesis in these leaves is more responsive to elevated [CO2] than leaves of C3 plants. To address this issue, we evaluated the response of gas exchange, water use efficiency, and photosynthetic efficiency of PSII by soybean (Glycine max (L.) Merr., 'Heihe35') of a typical C3 plant and maize (Zea mays L., 'Susheng') of C4 plant under four CO2 concentrations (500, 1000, 3000, and 5000 ppm), which were grown under controlled environmental conditions of Lunar Palace 1. The results showed that photosynthetic pigment by the C3 plants of soybean was more sensitive to elevated [CO2] below 3000 ppm than the C4 plants of maize. Elevated [CO2] to 1000 ppm induced a higher initial photosynthetic rate, while super-elevated [CO2] appeared to negate such initial growth promotion for C3 plants. The C4 plant had the highest ETR, φPSII, and qP under 500-3000 ppm [CO2], but then decreased substantially at 5000 ppm [CO2] for both species. Therefore, photosynthetic down-regulation and a decrease in photosynthetic electron transport occurred by both species in response to super-elevated [CO2] at 3000 and 5000 ppm. Accordingly, plants can be selected for and adapt to the efficient use of elevated CO2 concentration in LSS.

Energy consumption and output are two very important standards for evaluating the reliability of electric light sources when plants are grown in a controlled environment. As a primary source of energy, light is one of the most important environmental factors for wheat growth. The objective of this study was to investigate the influences of light/dark cycle operation with millisecond-scale period on the growth of wheat, photosynthetic characteristics, antioxidant capacity and biomass yield and quality during their life cycle. Four types of intermittent lighting with the same intensity were employed: a light/dark (0.5/0.5 ms) light (50%), a light/dark (0.7/0.3 ms) light (70%), a light/dark (0.8/0.2 ms) light (80%) and a continuous light (100%). The results showed that the wheat cultivated in the 80% light was characterized by highest photosynthetic rate and lowest lignin in inedible biomass, which was more beneficial to recycle substances in the processes of the environment regeneration. The data were comparable to those under continuous light condition in terms of chlorophyll concentration, antioxidant capacity, harvest index (HI) and thousand kernel weight (TKW). Wheat was sensitive to intermittent illumination which significantly affected those indices of growth and physiology, especially at heading and flowering stages., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

Silkworm (Bombyx mori L.) larvae were used as an ideal animal protein source for astronauts in the bioregenerative life support system (BLSS). Here, we compared the difference in bacterial communities of the silkworm larval gut between the BLSS rearing way (BRW) and the traditional rearing way (TRW) through culture-dependent approach, 16S rRNA gene analysis, and denaturing gradient gel electrophoresis (DGGE). The culture-dependent approach revealed that the numbers of gut bacteria of silkworm in the BRW significantly decreased compared with that of the TRW. The analysis of clone libraries showed that the gut microbiota in the BRW was significantly less diverse than that in the TRW. Acinetobacter and Bacteroides were dominant populations in the BRW, and Bacillus and Arcobacter dominated in the TRW. DGGE profiles confirmed the difference of silkworm gut bacterial community between two rearing ways. These results demonstrate that gut bacteria change from the BRW contributes to the decrease of silkworm physiological activity. This study increases our understanding of the change of silkworm gut microbiota in response to lettuce leaf feeding in the BRW. We could use the dominant populations to make probiotic products for nutrient absorption and disease prevention in the BLSS to improve gut microecology, as well as the yield and quality of animal protein.

Biofiltration of ethylene provides an environmentally friendly and economically beneficial option relative to physical/chemical removal, where selection of appropriate bed material is crucial. Here the vermicompost with indigenous microorganisms as bed material was evaluated for ethylene removal through batch test and biofilter experiment. Temporal and spatial dynamics of bacterial community in the vermicompost-biofilter under different ethylene loads were characterized by culture and denaturing gradient gel electrophoresis (DGGE) methods. The results showed that ethylene was effectively degraded by the vermicompost under conditions of 25-50% moisture content and 25-35°C temperature. The vermicompost-biofilter achieved nearly 100% ethylene removal up to an inlet load of 11mg m(-3)h(-1). Local nitrogen lack of the vermicompost in the biofilter was observed over operation time, but the change of pH was slight. DGGE analysis demonstrated that the bacterial abundance and community structure of vermicompost-biofilter varied with the height of biofilter under different ethylene loads. Pseudomonads and Actinobacteria were predominant in the biofilter throughout the whole experiment., (Copyright © 2011 Elsevier B.V. All rights reserved.)

To establish an economical and environmentally friendly technology for ethylene removal from horticultural facilities and industrial point sources, a bench-scale natural zeolite biofiltration system was developed in this study. The system was evaluated for its performance in removing ethylene from an artificially contaminated air stream and characterized for its bacterial diversity under varied ethylene concentrations, and in different spatial stages of the filter. The biofilter enabled to approximately 100% remove ethylene at loading rates of 0.26-3.76 g m(-3) h(-1) when operated with inoculum containing enriched ethylene-degrading bacteria. The bacterial diversity and abundance varied with the height of the biofilter. Moreover, the occurrence and predominance of specific bacterial species varied with the concentrations of ethylene introduced into the biofilter, as observed by PCR-DGGE methods. Phylogenetic analysis indicated that the biofilter system supported a diverse community of ethylene-degrading bacteria, with high similarity to species in the classes Betaproteobacteria, Gammaproteobacteria, Bacilli, and Actinobacteria., (Copyright © 2010 Elsevier Ltd. All rights reserved.)