Research progress of circRNA as a biomarker of sepsis: a narrative review.

OBJECTIVE: Explore the possibility of circRNAs as markers of sepsis. BACKGROUND: Sepsis is an abnormal immune response of our body to infection that can lead to organ failure and death. Although the research on sepsis has been extensive in the past few years, sepsis-associated morbidity and mortality are still increasing. Early diagnosis and early treatment are important for patients with sepsis. Although many markers, including procalcitonin and C-reactive protein, have been proposed as diagnostic indicators of sepsis, there are still challenges in the early diagnosis and treatment of sepsis due to the lack of sensitivity and specificity of these substances. Recently, a large number of studies have found that circular RNAs (circRNAs) participate in a variety of biological functions, such as immune response, regulating the expression of miRNAs, and they are closely related to the occurrence and development of many diseases, including sepsis. However, the clear mechanism of the role of circRNAs has not been fully elucidated. An increasing number of studies have confirmed that circRNAs have potential in the diagnosis and treatment of sepsis. By studying the regulatory mechanism of circRNAs in sepsis, we can search for new molecular intervention targets for the treatment of sepsis, which is conducive to the development of new molecular therapeutic drugs for sepsis. METHODS: In the present study, we summarize and analyze the role of circRNAs in the pathogenesis of sepsis and discuss the possibility of circRNA as a biomarker for the diagnosis of sepsis. CONCLUSIONS: The biological characteristics of circRNAs and their role in the occurrence and development of sepsis make them possible markers of sepsis.

A beneficial role of arbuscular mycorrhizal fungi in influencing the effects of silver nanoparticles on plant-microbe systems in a soil matrix.

Silver nanoparticles (AgNPs) are considered to be emerging contaminant for plant-soil systems. AM arbuscular mycorrhizal (AM) fungi can alleviate the negative effects of a variety of pollutants on their hosts, but its potential roles in influencing the toxicity of AgNPs and the underlying mechanisms are still an open question. This study investigated the responses of maize (Zea mays L.) inoculated with or without AM fungi and soil microorganisms to different concentrations of AgNPs (0, 0.025, 0.25, and 2.5 mg kg-1). The inoculation of AM fungi helps to alleviate the AgNP-induced phytotoxicity. Compared to the non-AM fungal inoculated treatments, AM fungal inoculation significantly increased the mycorrhizal colonization, biomass and phosphorus (P) acquisitions of maize, with an upregulation of P transporter gene expression under AgNP treatments. AM fungal inoculation decreased Ag content in plant shoots and roots, downregulated expression levels of genes involved in Ag transport and gene encoding a metallothionein involved in metal homeostasis. The beneficial role of AM fungi extended to soil microbes. Compared to the non-AM fungal inoculated treatments, AM fungal inoculation decreased the toxicity of AgNPs to soil microbial activities and bacterial abundance. AM fungal inoculation increased the bacterial diversity and induced changes in the soil bacterial community composition. Altogether, the present study revealed that AM fungal symbiosis can play beneficial roles in mediating the negative effects exposed by AgNPs on plants probably through changing the expressions of potential Ag transporters and cooperating with soil bacterial community.

Decolorization and detoxification of Direct Blue 2B by indigenous bacterial consortium.

Azo dyes are widely used in the textile industry despite being poorly biodegradable and highly toxic. Hence, azo dyes need to be removed from effluent prior to environmental discharge. Microbial communities are efficient for the degradation and mineralization of azo dyes. However, little is known about the functional microbial communities responsible for the degradation process. In this study, a novel indigenous bacteria consortium was developed for characterizing the functional microbial communities involved in the degradation of a sulfonated azo dye, Direct Blue 2B (DB2) in a simple batch reactor. The optimal temperature, pH, and salinity for the decolorization process were 38.70 °C, pH 7.57, and 20.10 g L-1 NaCl, respectively. The effect of the operating conditions on microbial community structure were determined using high-throughput Illumina HiSeq sequencing. Gammaproteobacteria, Betaproteobacteria, and Bacilli were dominant under most of the operating conditions. At pH above 8 and NaCl concentration above 30 g L-1, Firmicutes relative abundance did not significantly change suggesting tolerance towards alkaline and hypersaline environments. Tritium aestivum and Glycine max seed germination following exposure to YHK treated DB2 solution was above 80% compared to 50% in untreated DB2 solution. The YHK consortium decolorized dyes structurally different from DB2 such as trimethyl phenyl and direct dyes. The results of this study offer valuable data on improving optimization of dye biodegradation processes and the capability of YHK in in situ bioremediation.

[Effects of O3-FACE(ozone-free air control enrichment) on gas exchange and chlorophyll fluorescence of rice leaf].

O3-FACE (Ozone-free air control enrichment) platform has been established for observing the effect of elevated tropospheric ozone concentration on the gas exchange and chlorophyll fluorescence of two rice varieties (Wuyunjing 21 and Liangyoupeijiu). The results showed that high ozone concentration decreased the net photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate (Tr) of rice leaves. After 76d fumigation the decline in them for Wuyunjing 21 was as follows: 21.7%, 26.64% and 24.74% respectively, and that for Liangyoupeijiu was as follows: 25.53%, 30.31% and 25.48% respectively; however, no significant impact on leaf intercellular CO2 concentration was observed. Chlorophyll fluorescence kinetics parameters changed as can be seen by the decrease in F0 (initial fluorescence in the dark), ETR (The apparent electron transfer rate) and psiPSII (actual photochemical efficiency of PS II in the light), and the increase in NPQ (non-photochemical quenching). After 76 days of O3 treatment, the NPQ of Wuyunjing 21 and Liangyoupeijiu was enhanced by 16.37% and 11.77%, respectively. The impact of ozone on rice was a cumulative effect, and the extent of variation in the above parameters and the differences between the two varieties were enlarged as the O3 treatment time increased; At the same time because the rice leaf intercellular CO2 concentration did not significantly reduce, the inferred decrease in net photosynthetic rate was restricted by non-stomatal factors. The results of this experiment indicated that Liangyoupeijiu was more susceptible to ozone than Wuyunjing 21.

Elevated CO2 accelerates flag leaf senescence in wheat due to ear photosynthesis which causes greater ear nitrogen sink capacity and ear carbon sink limitation.

It was anticipated that wheat net photosynthesis would rise under elevated CO2, and that this would alter the progress of senescence due to the unbalance of carbohydrates and nitrogen. Our study showed that ear carbon sink was limited, and sugar was accumulated, hexokinase activities and levels of phosphorylated sugar were increased within the flag leaves, grain nitrogen sink capacity was enhanced, and flag leaf senescence was accelerated under elevated CO2. However, if the ear of the main stem was covered, these responses to elevated CO2 were absent, and the senescence of flag leaf was not accelerated by elevated CO2. Thus, it appeared that elevated CO2 accelerated the rate of flag leaf senescence, depending on ear photosynthesis. The ears have far higher enhancement of net photosynthesis than flag leaves, and the role of the flag leaf relative to the ear was declined in supplying C assimilation to grain under elevated CO2. This indicates that as CO2 rises, the grain sink needs the N more than C assimilate from flag leaf, so the declining rates of N% and soluble proteins concentration were markedly accelerated under elevated CO2 conditions. This suggests that, the large increase in ear net photosynthesis accelerated grain filling, accelerated remobilising N within flag leaf as the result of the greater grain nitrogen sink capacity. In addition, as the result of grain carbon sink limitation, it limited the export of flag leaf sucrose and enhanced sugar cycling, which was the signal to accelerate leaf senescence. Hence, elevated CO2 subsequently accelerates senescence of flag leaf.