Tracing the evolving dynamics and research hotspots of microbiota and immune microenvironment from the past to the new era.

Gut microbiota can regulate many physiological processes within gastrointestinal tract and other distal sites. Dysbiosis may not only influence chronic diseases like the inflammatory bowel disease (IBD), metabolic disease, tumor and its therapeutic efficacy, but also deteriorate acute injuries. This article aims to review the documents in this field and summarize the research hotspots as well as developing processes. Gut microbiota and immune microenvironment-related documents from 1976 to 2022 were obtained from the Web of Science Core Collection database. Bibliometrics was used to assess the core authors and journals, most contributive countries and affiliations together with hotspots in this field and keyword co-occurrence analysis. Data were visualized to help comprehension. Nine hundred and twelve documents about gut microbiota and immune microenvironment were retrieved, and the annual publications increased gradually. The most productive author, country, and affiliation were "Zitvogel L," USA and "UNIV TEXAS MD ANDERSON CANC CTR," respectively. FRONTIERS IN IMMUNOLOGY, CANCERS, and INTERNATIONAL JOURNAL OF MOLECULAR SCIENCE were the periodicals with most publications. Keyword co-occurrence analysis identified three clusters, including gut microbiota, inflammation, and IBD. Combined with the visualized analysis of documents and keyword co-occurrence as well as literature reading, we recognized three key topics of gut microbiota: cancer and therapy; immunity, inflammation and IBD; acute injuries and metabolic diseases. This article revealed researches on gut microbiota and immune microenvironment were growing. More attention should be given to the latest hotspots like gut microbiota, inflammation, IBD, cancer and immunotherapy, acute traumas, and metabolic diseases.IMPORTANCEGut microbiota can regulate many physiological processes within gastrointestinal tract and other distal sites. Dysbiosis may not only influence chronic diseases like inflammatory bowel disease (IBD), metabolic disease, tumor and its therapeutic efficacy, but also deteriorate acute injuries. While the application of bibliometrics in the field of gut microbiota and immune microenvironment still remains blank, which focused more on the regulation of the gut microbiota on the immune microenvironment of different kinds of diseases. Here, we intended to review and summarize the presented documents in gut microbiota and immune microenvironment field by bibliometrics. And we revealed researches on gut microbiota and immune microenvironment were growing. More attention should be given to the latest hotspots like gut microbiota, inflammation, IBD, cancer and immunotherapy, acute traumas, and metabolic diseases.

Effects of climate change and grazing intensity on grassland productivity-A case study of Inner Mongolia, China.

In the last 30 years, grassland productivity has declined seriously due to climate variations and unreasonable human activities. Therefore, to analyze the impact of different factors on grassland productivity, we selected three grassland stations of the Typical Steppe from west to east and collected 38 years of data. The Pearson Correlation and Fixed Effect Model were used to analyze the impact of precipitation, temperature, and grazing intensity on grassland productivity. The empirical results show that precipitation positively and significantly affected grassland productivity. The effects of climate change are more significant than human activities, but the impact of temperature is greater than precipitation. The synergy between precipitation and temperature was greater than between precipitation and temperature separately. In addition, the effects of climate change and human activities on grassland productivity have evident regional heterogeneity. The variation trend gradually increases from west to east in factors that affect grassland productivity. Therefore, we suggest some implications for grassland risk management, such as utilizing some financial products for climate risk and focusing on the synergy index to design financial products, such as design weather derivatives. Lastly, we should strengthen the research on the relationship between climate change and grassland productivity to provide a scientific basis for revealing the intrinsic relationship between climate, human activities, and grassland productivity.

L-Tyrosine Limits Mycobacterial Survival in Tuberculous Granuloma.

Caused by the intracellular pathogen Mycobacterium tuberculosis (Mtb), tuberculosis (TB) remains a massive global public health issue. A well-known and key TB trait is caseous necrotic granuloma, which allows mycobacteria to reactivate and disseminate, thus confounding TB eradication programs. Amino acid (AA) metabolism is key to regulating immune responses in Mtb infections; however, it is currently unclear if AAs can be used to treat tuberculous granulomas. Here, we screened 20 proteinogenic AAs using a Mycobacterium marinum-infected zebrafish granuloma model. Only L-tyrosine simultaneously reduced Mycobacterium marinum (M. marinum) levels in zebrafish larvae and adults and inhibited intracellular pathogen survival levels. Mechanistically, L-tyrosine significantly upregulated interferon-γ (IFN-γ) expression in M. marinum -infected zebrafish adults but not in larvae. Using N-acetylcysteine (NAC) to inhibit reactive oxygen species (ROS), L-tyrosine appeared to inhibit Mtb intracellular survival by promoting ROS production. Thus, L-tyrosine as a non-essential AA may reduce mycobacterial survival in both macrophages and tuberculous granulomas. Our research provides a platform for the clinical development of AAs for active or latent TB patients infected with drug-sensitive or drug-resistant Mtb.

Mapping intellectual structure and research hotspots in the field of fibroblast-associated DFUs: a bibliometric analysis.

Background: Diabetic foot ulcers (DFUs) are one of the most popular and severe complications of diabetes. The persistent non-healing of DFUs may eventually contribute to severe complications such as amputation, which presents patients with significant physical and psychological challenges. Fibroblasts are critical cells in wound healing and perform essential roles in all phases of wound healing. In diabetic foot patients, the disruption of fibroblast function exacerbates the non-healing of the wound. This study aimed to summarize the hotspots and evaluate the global research trends on fibroblast-related DFUs through bibliometric analysis. Methods: Scientific publications on the study of fibroblast-related DFUs from January 1, 2000 to April 27, 2022 were retrieved from the Web of Science Core Collection (WoSCC). Biblioshiny software was primarily performed for the visual analysis of the literature, CiteSpace software and VOSviewer software were used to validate the results. Results: A total of 479 articles on fibroblast-related DFUs were retrieved. The most published countries, institutions, journals, and authors in this field were the USA, The Chinese University of Hong Kong, Wound Repair and Regeneration, and Seung-Kyu Han. In addition, keyword co-occurrence networks, historical direct citation networks, thematic map, and the trend topics map summarize the research hotspots and trends in this field. Conclusion: Current studies indicated that research on fibroblast-related DFUs is attracting increasing concern and have clinical implications. The cellular and molecular mechanisms of the DFU pathophysiological process, the molecular mechanisms and therapeutic targets associated with DFUs angiogenesis, and the measures to promote DFUs wound healing are three worthy research hotspots in this field.

Sequencing technology as a major impetus in the advancement of studies into rheumatism: A bibliometric study.

Background: Rheumatism covers a wide range of diseases with complex clinical manifestations and places a tremendous burden on humans. For many years, our understanding of rheumatism was seriously hindered by technology constraints. However, the increasing application and rapid advancement of sequencing technology in the past decades have enabled us to study rheumatism with greater accuracy and in more depth. Sequencing technology has made huge contributions to the field and is now an indispensable component and powerful tool in the study of rheumatism. Methods: Articles on sequencing and rheumatism, published from 1 January 2000 to 25 April 2022, were retrieved from the Web of Science™ (Clarivate™, Philadelphia, PA, USA) database. Bibliometrix, the open-source tool, was used for the analysis of publication years, countries, authors, sources, citations, keywords, and co-words. Results: The 1,374 articles retrieved came from 62 countries and 350 institutions, with a general increase in article numbers during the last 22 years. The leading countries in terms of publication numbers and active cooperation with other countries were the USA and China. The most prolific authors and most popular documents were identified to establish the historiography of the field. Popular and emerging research topics were assessed by keywords and co-occurrence analysis. Immunological and pathological process in rheumatism, classification, risks and susceptibility, and biomarkers for diagnosis were among the hottest themes for research. Conclusions: Sequencing technology has been widely applied in the study of rheumatism and propells research in the area of discovering novel biomarkers, related gene patterns and physiopathology. We suggest that further efforts be made to advance the study of genetic patterns related to rheumatic susceptibility, pathogenesis, classification and disease activity, and novel biomarkers.

Fire Extinguishing Performance of Chemically Bonded Struvite Ceramic Powder with High Heat-Absorbing and Flame Retardant Properties.

Struvite is a chemically bonded ceramic product in the pipeline of a sewage treatment plant. In order to explore the fire extinguishing potential of struvite, a new type of struvite ultrafine dry powder with excellent performance was prepared by a simple process, and its fire extinguishing performance and mechanism were analyzed in depth. Under the same process conditions, the refinement degree (D50 = 5.132 µm) and the specific surface area (BET = 25.72 m2/g) of ultrafine struvite were larger than those of NH4H2PO4 (D50 = 8.961 µm, BET = 13.64 m2/g), making struvite more suitable for fire extinguishing. Besides, the pyrolysis process of struvite was relatively concentrated and absorbed more heat in a short time. Its heat absorption (458.4 J/mg) was higher than that of NH4H2PO4 (156.4 J/mg). Water, ammonia, and PO· were released during the pyrolysis of struvite, which effectively reduced fire temperature, diluted oxygen concentrations and captured free radicals. At the same time, the final products were magnesium orthophosphate and magnesium pyrophosphate, which formed a dense flame-retardant ceramic layer with good thermal insulation and environmental protection functions. In these cases, the fire extinguishing mechanism of struvite was determined to have three stages: the cooling effect, the asphyxiation effect, and the chemical effect. Correspondingly, the fire extinguishing time of struvite was three seconds faster than that of ammonium phosphate under 0.2 MPa based on the local oil basin test.

Correction: Ye et al. Investigation of the JASMONATE ZIM-DOMAIN Gene Family Reveals the Canonical JA-Signaling Pathway in Pineapple. Biology 2022, 11, 445.

The authors would like to make the following correction to the published paper [...].

Investigation of the JASMONATE ZIM-DOMAIN Gene Family Reveals the Canonical JA-Signaling Pathway in Pineapple.

JASMONATE ZIM-DOMAIN (JAZ) proteins are negative regulators of the jasmonate (JA)-signaling pathway and play pivotal roles in plant resistance to biotic and abiotic stresses. Genome-wide identification of JAZ genes has been performed in many plant species. However, systematic information about pineapple (Ananas comosus L. Merr.) JAZ genes (AcJAZs) is still not available. In this study, we identified 14 AcJAZ genes and classified them into five groups along with the Arabidopsis and rice orthologs. The AcJAZ genes have 3-10 exons, and the putative AcJAZ proteins have between two and eight conserved regions, including the TIFY motif and Jas domain. The cis-acting element analysis revealed that the putative promoter regions of AcJAZs contain between three and eight abiotic stress-responsive cis-acting elements. The gene-expression analysis suggested that AcJAZs were expressed differentially during plant development and subjected to regulation by the cold, heat, salt, and osmotic stresses as well as by phytohormones. Moreover, the BiFC analysis of protein interactions among the central JA-signaling regulators showed that AcJAZ4, AcMYC2, AcNINJA, and AcJAM1 could interact with AcJAZ5 and AcJAZ13 in vivo, indicating a canonical JA-signaling pathway in pineapple. These results increase our understanding of the functions of AcJAZs and the responses of the core players in the JA-signaling pathway to abiotic stresses.

Interception of host fatty acid metabolism by mycobacteria under hypoxia to suppress anti-TB immunity.

Pathogenic mycobacteria induce the formation of hypoxic granulomas during latent tuberculosis (TB) infection, in which the immune system contains, but fails to eliminate the mycobacteria. Fatty acid metabolism-related genes are relatively overrepresented in the mycobacterial genome and mycobacteria favor host-derived fatty acids as nutrient sources. However, whether and how mycobacteria modulate host fatty acid metabolism to drive granuloma progression remains unknown. Here, we report that mycobacteria under hypoxia markedly secrete the protein Rv0859/MMAR_4677 (Fatty-acid degradation A, FadA), which is also enriched in tuberculous granulomas. FadA acts as an acetyltransferase that converts host acetyl-CoA to acetoacetyl-CoA. The reduced acetyl-CoA level suppresses H3K9Ac-mediated expression of the host proinflammatory cytokine Il6, thus promoting granuloma progression. Moreover, supplementation of acetate increases the level of acetyl-CoA and inhibits the formation of granulomas. Our findings suggest an unexpected mechanism of a hypoxia-induced mycobacterial protein suppressing host immunity via modulation of host fatty acid metabolism and raise the possibility of a novel therapeutic strategy for TB infection.

Molecular cloning and functional characterization of GmAAPTs from soybean (Glycine max).

Aminoalcoholphosphotransferase (AAPT) utilizes diacylglycerols and cytidine diphosphate-choline/ethanolamine as substrates for the synthesis of phosphatidylcholine (PC)/phosphatidylethanolamine (PE). Plant AAPTs involved in phospholipid metabolism mediate diverse physiological processes; however, little is known about their functions in triacylglycerol (TAG) metabolism and seed germination. In the present study, we isolated and characterized two AAPTs, GmAAPT1 and GmAAPT2, from soybean (Glycine max). GmAAPT1 and GmAAPT2 exhibited strong similarity in their amino acid contents and expression patterns, and both were found to localize to the endoplasmic reticulum and Golgi apparatus. In vitro enzymatic analyses showed that GmAAPT1 and GmAAPT2 contributed to PC and PE synthesis and exhibited choline/ethanolamine phosphotransferase-like enzymatic properties. The overexpression of GmAAPT1 and GmAAPT2 in Arabidopsis led to reduced levels of seed TAG and polyunsaturated fatty acids and decreased seed germination under freezing stress. Together, these findings suggest that GmAAPTs mediate TAG metabolism and negatively regulate seed freezing tolerance.

Hypercrosslinked phenothiazine-based polymers as high redox potential organic cathode materials for lithium-ion batteries.

Organic cathode materials have been demonstrated to be highly promising sustainable cathode materials for rechargeable lithium-ion batteries. However, the low redox potentials, low electrical conductivity, and the undesirable dissolution in organic electrolytes greatly limit their applications. Herein, two insoluble hypercrosslinked porous conductive polymers with phenothiazine motifs, HPEPT and HPPT, were successfully accomplished with high and stable discharge potentials at 3.65 and 3.48 V versus Li/Li+. HPEPT and HPPT with good electrical conductivity exhibited outstanding rate capabilities (up to 800 mA g-1) even at a high mass loading up to 70 wt%. This study shows that excellent organic cathode materials could be achieved readily through this prudent design.

Notch1a can widely mediate innate immune responses in zebrafish larvae infected with Vibrio parahaemolyticus.

The Notch signaling pathway is known to regulate innate immunity by influencing macrophage function and interacting with the Toll-like receptor (TLR) signaling pathway. However, the comprehensive role of the Notch signaling pathway in the innate immune response remains unknown. To assess the function of Notch1a in immunity, we examined the innate immune responses to Vibrio parahaemolyticus strain Vp13 of wild-type (WT) and notch1a-/- zebrafish larvae generated using the clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9) system. The median lethal dose (LD50) of V. parahaemolyticus was significantly lower in notch1a-/- larvae than in WT larvae 3 days post fertilization (dpf). Transcriptome data analysis revealed 359 significantly differentially expressed genes (DEGs), including 246 significantly down-regulated genes and 113 significantly up-regulated genes, in WT infected groups compared with WT control groups. In contrast, 986 significantly DEGs were found in notch1a-/- infected groups compared with notch1a-/- control groups, of which 82 genes were significantly down-regulated and 904 genes were significantly up-regulated. These DEGs belonged to the tumor necrosis factor (TNF), complement, nuclear factor kappa B (NF-κB), cathepsin, interleukin (IL), chemokine, serpin peptidase inhibitor, matrix metallopeptidase, innate immune cells, pattern recognition receptor (PRR), and other cytokine families. Our results indicate that Notch1a plays roles in inhibiting many immunity-related genes and could comprehensively mediate the innate immune response by regulating TLRs, nucleotide-binding-oligomerization-domain-like receptors (NLRs), lectins, complement, ILs, chemokines, TNF, cathepsin, and serpin. Further studies are required to understand the specific mechanism of Notch1a in innate immunity.

Transcriptomic analysis of microRNAs-mRNAs regulating innate immune response of zebrafish larvae against Vibrio parahaemolyticus infection.

In recent years, microRNAs (miRNAs) have been shown to play important roles in immunity. Analyses of the functions of miRNAs and their targets are useful in understanding the regulation of the immune response. To understand the relationships between miRNAs and their targets during infection, we used zebrafish as an infection model in which to characterize the miRNA and mRNA transcriptomes of zebrafish larvae infected with Vibrio parahaemolyticus. We identified the differentially expressed miRNAs and mRNAs. Overall, 37 known zebrafish miRNAs were differentially expressed in the infection group and 107 predicted target genes of 26 miRNAs were differentially expressed in the mRNA transcriptome. These targets with specific Gene Ontology (GO) terms, such as peripheral nervous system neuron axonogenesis, organophosphate metabolic process, heme binding, protein binding, tetrapyrrole binding, protein dimerization activity, and aromatase activity, which regulate nerve conduction, energy metabolism, hematopoiesis, and protein synthesis. They were also associated with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways such as phototransduction, tryptophan metabolism, notch signaling, and purine metabolism. Our findings indicate that miRNAs regulate the innate immune response via complex networks, and zebrafish (Danio rerio, dre)-miR-205-3p, dre-miR-141-5p, dre-miR-200a-5p, dre-miR-92a-2-5p, dre-miR-192, and dre-miR-1788 may play important roles in the innate immune response by regulating target genes.