Protective effects of Prussian blue nanozyme against sepsis-induced acute lung injury by activating HO-1.

Sepsis is a life-threatening condition involving dysfunctional organ responses stemming from dysregulated host immune reactions to various infections. The lungs are most prone to failure during sepsis, resulting in acute lung injury (ALI). ALI is associated with oxidative stress and inflammation, and current therapeutic strategies are limited. To develop a more specific treatment, this study aimed to synthesise Prussian blue nanozyme (PBzyme), which can reduce oxidative stress and inflammation, to alleviate ALI. PBzyme with good biosafety was synthesised using a modified hydrothermal method. PBzyme was revealed to be an activator of haem oxygenase-1 (HO-1), improving survival rate and ameliorating lung injury in mice. Zinc protoporphyrin, an inhibitor of HO-1, inhibited the prophylactic therapeutic efficacy of PBzyme on ALI, and affected the nuclear factor-κB signaling pathway and activity of HO-1. This study demonstrates that PBzyme can alleviate oxidative stress and inflammation through HO-1 and has a prophylactic therapeutic effect on ALI. This provides a new strategy and direction for the clinical treatment of sepsis-induced ALI.

Micro-biological degradation and transformation of dissolved organic matter following continuous cropping of tobacco.

In recent years, the problems associated with continuous cropping (CC) that cause soil degradation have become increasingly serious. As a key soil quality property, dissolved organic matter (DOM) affects the circulation of carbon and nutrients and the composition of bacterial communities in soil. However, research on the changes in the molecular composition of DOM after CC is limited. In this study, the soil chemical properties, DOM chemical diversity, bacterial community structure, and their interactions are explored in the soil samples from different CC years (CC1Y, CC3Y, CC5Y, and CC7Y) of tobacco. With increasing CC year of tobacco, most of the soil chemical properties, such as total carbon, total nitrogen and organic matter, decreased significantly, while dissolved organic carbon first decreased and then increased. Likewise, the trends of DOM composition differed with changing duration of CC, such as the tannin compounds decreased from 18.13 to 13.95%, aliphatic/proteins increased from 2.73 to 8.85%. After 7 years of CC, the soil preferentially produced compounds with either high H/C ratios (H/C > 1.5), including carbohydrates, lipids, and aliphatic/proteins, or low O/C ratios (O/C < 0.1), such as unsaturated hydrocarbons. Furthermore, core microorganisms, including Nocardioides, wb1-P19, Aquabacterium, Methylobacter, and Thiobacillus, were identified. Network analysis further indicated that in response to CC, Methylobacter and Thiobacillus were correlated with the microbial degradation and transformation of DOM. These findings will improve our understanding of the interactions between microbial community and DOM in continuous cropping soil.

Behavioral and molecular response of the insect parasitic nematode Steinernema carpocapsae to plant volatiles.

Entomopathogenic nematodes (EPNs) use the chemical cues emitted by insects and insect-damaged plants to locate their hosts. Steinernema carpocapsae, a species of EPN, is an established biocontrol agent used against insect pests. Despite its promising potential, the molecular mechanisms underlying its ability to detect plant volatiles remain poorly understood. In this study, we investigated the response of S. carpocapsae infective juveniles (IJs) to 8 different plant volatiles. Among these, carvone was found to be the most attractive volatile compound. To understand the molecular basis of the response of IJs to carvone, we used RNA-Seq technology to identify gene expression changes in response to carvone treatment. Transcriptome analysis revealed 721 differentially expressed genes (DEGs) between carvone-treated and control groups, with 403 genes being significantly upregulated and 318 genes downregulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the responsive DEGs to carvone attraction were mainly involved in locomotion, localization, behavior, response to stimulus, and olfactory transduction. We also identified four upregulated genes of chemoreceptor and response to stimulus that were involved in the response of IJs to carvone attraction. Our results provide insights into the potential transcriptional mechanisms underlying the response of S. carpocapsae to carvone, which can be utilized to develop environmentally friendly strategies for attracting EPNs.

tRF3-IleAAT reduced extracellular matrix synthesis in diabetic kidney disease mice by targeting ZNF281 and inhibiting ferroptosis.

It is well established that the synthesis of extracellular matrix (ECM) in mesangial cells is a major determinant of diabetic kidney disease (DKD). Elucidating the major players in ECM synthesis may be helpful to provide promising candidates for protecting against DKD progression. tRF3-IleAAT is a tRNA-derived fragment (tRF) produced by nucleases at tRNA-specific sites, which is differentially expressed in the sera of patients with diabetes mellitus and DKD. In this study we investigated the potential roles of tRFs in DKD. Db/db mice at 12 weeks were adapted as a DKD model. The mice displayed marked renal dysfunction accompanied by significantly reduced expression of tRF3-IleAAT and increased ferroptosis and ECM synthesis in the kidney tissues. The reduced expression of tRF3-IleAAT was also observed in high glucose-treated mouse glomerular mesangial cells. We administered ferrostatin-1 (1 mg/kg, once every two days, i.p.) to the mice from the age of 12 weeks for 8 weeks, and found that inhibition of the onset of ferroptosis significantly improved renal function, attenuated renal fibrosis and reduced collagen deposition. Overexpression of tRF3-IleAAT by a single injection of AAV carrying tRF3-IleAAT via caudal vein significantly inhibited ferroptosis and ECM synthesis in DKD model mice. Furthermore, we found that the expression of zinc finger protein 281 (ZNF281), a downstream target gene of tRF3-IleAAT, was significantly elevated in DKD models but negatively regulated by tRF3-IleAAT. In high glucose-treated mesangial cells, knockdown of ZNF281 exerted an inhibitory effect on ferroptosis and ECM synthesis. We demonstrated the targeted binding of tRF3-IleAAT to the 3'UTR of ZNF281. In conclusion, tRF3-IleAAT inhibits ferroptosis by targeting ZNF281, resulting in the mitigation of ECM synthesis in DKD models, suggesting that tRF3-IleAAT may be an attractive therapeutic target for DKD.

High-resolution chemical imaging to understand Cd activation in rice rhizosphere of karstic soils.

Cadmium (Cd) activation, especially at a high spatial resolution, in paddy soils with a high geogenic Cd background is yet to be understood. To investigate the temporal and spatial patterns of Cd activation in rice rhizosphere, pot and rhizotron experiments were conducted using four paddy soils with high geogenic Cd (0.11-3.70 mg kg-1) from Guangxi, southwestern China. The pot experiment results showed that porewater Cd concentrations initially decreased and then increased over the complete rice growth period, reaching its lowest value during the late-tillering and early-filling stages. Besides, correlation analysis identified organic matter and root manganese (Mn) content as the main factors affecting rice Cd uptake, with Mn having a negative effect and organic matter having a positive effect. Sub-millimeter two-dimensional chemical imaging revealed that the distribution of labile Cd in the rhizosphere (by diffusive gradients in thin-films, or DGT) was influenced by the root system and soil properties, such as pH (by planar optode) and acid phosphatase activity (by soil zymography). Soil acid phosphatase activity increased under Cd stress. The overall pH at rice rhizosphere decreased. Moreover, a close relationship was found between the spatial distributions of soil labile Mn and Cd at the rhizosphere, with higher Mn being associated with lower Cd lability. This study highlights Mn as a key element in regulating rice Cd uptake and enlightens future Mn-based strategies for addressing Cd pollution in rice paddy soils, especially in karst areas with high geochemical background.

Satellite cell-derived exosome-mediated delivery of microRNA-23a/27a/26a cluster ameliorates the renal tubulointerstitial fibrosis in mouse diabetic nephropathy.

Renal tubulointerstitial fibrosis (TIF) is considered as the final convergent pathway of diabetic nephropathy (DN) without effective therapies currently. MiRNAs play a key role in fibrotic diseases and become promising therapeutic targets for kidney diseases, while miRNA clusters, formed by the cluster arrangement of miRNAs on chromosomes, can regulate diverse biological functions alone or synergistically. In this study, we developed clustered miR-23a/27a/26a-loaded skeletal muscle satellite cells-derived exosomes (Exos) engineered with RVG peptide, and investigated their therapeutic efficacy in a murine model of DN. Firstly, we showed that miR-23a-3p, miR-26a-5p and miR-27a-3p were markedly decreased in serum samples of DN patients using miRNA sequencing. Meanwhile, we confirmed that miR-23a-3p, miR-26a-5p and miR-27a-3p were primarily located in proximal renal tubules and highly negatively correlated with TIF in db/db mice at 20 weeks of age. We then engineered RVG-miR-23a/27a/26a cluster loaded Exos derived from muscle satellite cells, which not only enhanced the stability of miR-23a/27a/26a cluster, but also efficiently delivered more miR-23a/27a/26a cluster homing to the injured kidney. More importantly, administration of RVG-miR-23a/27a/26a-Exos (100 µg, i.v., once a week for 8 weeks) significantly ameliorated tubular injury and TIF in db/db mice at 20 weeks of age. We revealed that miR-23a/27a/26a-Exos enhanced antifibrotic effects by repressing miRNA cluster-targeting Lpp simultaneously, as well as miR-27a-3p-targeting Zbtb20 and miR-26a-5p-targeting Klhl42, respectively. Knockdown of Lpp by injection of AAV-Lpp-RNAi effectively ameliorated the progression of TIF in DN mice. Taken together, we established a novel kidney-targeting Exo-based delivery system by manipulating the miRNA-23a/27a/26a cluster to ameliorate TIF in DN, thus providing a promising therapeutic strategy for DN.

[Retracted] KIFC1 promotes the proliferation of hepatocellular carcinoma in vitro and in vivo.

[This retracts the article DOI: 10.3892/ol.2019.10985.].

Conversion of THz refractive index variation to detectable voltage change realized by a graphene-based Brewster angle device.

The Brewster effect has been previously reported as an essential mechanism for terahertz (THz) wave sensing application. However, generally in a sensing application, a complex rotation apparatus is required for detecting the slight change in Brewster angle. Here, we propose a graphene-based Brewster angle device operating at a specific terahertz frequency capable of sensing the refractive index at a fixed incident angle. In other words, our sensing device could avoid the impact of Brewster angle shift and eliminate the need for high-precision rotating equipment, which is usually required in traditional sensing applications. The conversion from the refractive index to a Volt-level detectable voltage roots from the tunability of graphene's Fermi level in the external electrical field. A linear correlation between the output voltage and the background refractive index is observed and theocratically analyzed. Furthermore, we present the improvement of our device in terms of sensing range and sensitivity by adjusting the permittivity of the dielectric substrate. As a demonstration of our proposed device, a detection range of 1.1-2.4 and a sensitivity of 20.06 V/RIU for refractive index is achieved on a high-resistance silicon substrate operating at 0.3 THz.

[Vertical Differences in Grassland Bacterial Community Structure During Non- Growing Season in Eastern Ulansuhai Basin].

Grassland is an important part of the regional ecosystem, and its micro ecological structures play key roles in the process of element migration and the evolution of ecological diversity systems. To discover the spatial difference of the grassland soil bacterial community, we collected five total soil samples at 30 cm depth and 60 cm depth in Eastern Ulansuhai Basin in early May (before the beginning of the new growing season, with a minimum influence of human activities and other factors). Based on 16S rRNA gene-based high-throughput sequencing technology, the vertical characteristic of the bacterial community was analyzed in detail. First, Actinobacteriota, Proteobacteria, Chloroflexi, Acidobacteriota, Gemmatimonadota, Planctomycetota, Methylomirabilota, and Crenarchacota all appeared in the 30 cm and 60 cm samples, with the relative contents all being higher than 1%. In addition, there were a total of six phyla, five genera, and eight OTUs in the 60 cm sample with relative contents higher than those in the 30 cm sample. As a result, the relative abundance changes in dominant bacterial phyla, genera, and even OTUs at different sample depths did not correspond to their contribution to the bacterial community structure. Second, because of the unique contribution to the bacterial community structure in 30 cm and 60 cm samples, the norank_f__norank_o__norank_c__norank_p__Armatimonadota and Candidatus_Xiphinematobacter could be utilized as key bacterial genera during ecological system analysis, belonging to the Armatimonadota and Verrucomicrobiota, respectively. Finally, the relative abundances of ko00190, ko00910, and ko01200 were all higher in 60 cm samples than those in 30 cm samples, which showed that through the increase in metabolic function abundance, the relative contents of C, N, and P elements in grassland soil had been reduced with the increase in depth. These results will provide references for further study on the spatial change of bacterial communities in typical grassland.

[Association Between Socioeconomic Status, Productive Aging, and Frailty Index in Urban Elderly Population in China].

Objective: To explore the impact of socioeconomic status and productive aging on the frailty index of urban elderly population in China, and to provide reference for improving their health level. Methods: We obtained data from the 2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS) and included 1890 urban elderly people aged 60 and over in the study. Multiple linear regression model was used to analyze the influencing factors of the productive aging and the frailty index of the urban elderly population in China. A structural equation model was constructed to explore the relationship between socioeconomic status, productive aging, and frailty index. Results: Elderly people with high socioeconomic status ( ß=0.082, P<0.001) had higher level of productive aging. Elderly people with high socioeconomic status ( ß=－0.091, P<0.001) and high level of productive aging ( ß=－0.330, P<0.001) had lower frailty index. Productive aging played an intermediary role ( ß=－0.259, 95% CI: －0.380--0.181) between socioeconomic status and frailty index. Conclusion: The socioeconomic status and productive aging of the elderly people are important predictors of their frailty index. The government should exert its leadership functions to encourage the elderly, especially those with low education and income levels, to actively learn knowledge and skills, and to provide support for the elderly to participate in productive activities.

Chemometrics applied quantitative analysis of iron oxide mixtures by terahertz spectroscopy.

A quantitative analysis method for corrosion products based on terahertz spectroscopy is proposed in this paper. Mixture samples consisting of three major corrosion products (magnetite, hematite, and goethite) were prepared in 51 different concentrations. The refractive index spectra measured by terahertz time-domain spectroscopy were projected to the 2D score diagram by performing principal component analysis. The Euclidean distances between the mixtures and pure analyte on the diagram were used to build a concentration prediction model. The results indicate that the established model can precisely predict the concentration of magnetite, which is essential for a stability evaluation of the corrosion system.

Transcriptomic analysis provides insight into defensive strategies in response to continuous cropping in strawberry (Fragaria × ananassa Duch.) plants.

BACKGROUND: Strawberries are an important economic fruit crop world-wide. In strawberry cultivation, continuous cropping (CC) can seriously threaten yield and quality. However, our understanding of the gene expression changes in response to CC and during subsequent defense processes is limited. In this study, we analyzed the impact of CC on the transcriptome of strawberry roots using RNA-Seq technology to elucidate the effect of CC and the subsequent molecular changes. RESULTS: We found that CC significantly affects the growth of strawberry plants. The transcriptome analysis identified 136 differentially expressed genes (DEGs), including 49 up-regulated and 87 down-regulated DEGs. A Gene Ontology (GO) analysis indicated that the up-regulated DEGs were mainly assigned to defense-related GO terms, and most down-regulated DEGs were assigned to nutrient-related GO terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the responsive DEGs were classified in a large number of important biological pathways, such as phenylalanine metabolism, starch and sucrose metabolism, phenylpropanoid biosynthesis, glutathione metabolism and plant-pathogen interaction. We also found that four WRKY transcription factors and three peroxidase genes involved in plant defense pathways were up-regulated in the roots of strawberry plants subjected to CC. CONCLUSION: Several unigenes involved in plant defense processes, such as CNGCs, WRKY transcription factors, PR1, and peroxidase genes with highly variable expression levels between non-CC and CC treatments may be involved in the regulation of CC in strawberry. These results indicate that strawberry roots reallocate development resources to defense mechanisms in response to CC. This study will further deepen our understanding of the fundamental regulatory mechanisms of strawberry resource reallocation in response to CC.

Enhancing the efficiency of graphene-based THz modulator by optimizing the Brewster angle.

The gate-controllable electronical property of graphene provides a possibility of active tuning property for THz modulator. However, the common modulation technology which only depends on voltage cannot solve the problem of power consumption limitation in communication applications. Here, we demonstrated a Brewster angle-controlled graphene-based THz modulator, which could achieve a relatively high modulation depth with low voltage. First, we explored the complex relationships among the Brewster angles, reflection coefficients and the conductivities of graphene. Then, we further investigated the optimal incident angle selection based on the unusual reflection effect which occurs at Brewster angle. Finally, an improved scheme by dynamically adjusting the incident angle was proposed in this paper. It would make it possible that the modulator could achieve a modulation depth of more than 90% with a Fermi level as low as 0.2eV at any specific frequency in the range of 0.4THz-2.2THz. This research will help to realize a THz modulator with high-performance and ultra-low-power in quantities of applications, such as sensing and communication.

Transcriptomic analysis reveals recovery strategies in strawberry roots after using a soil amendment in continuous cropping soil.

BACKGROUND: In strawberry cultivation, continuous cropping (CC) obstacles seriously threaten production. A patented soil amendment (SA) can effectively relieve the CC obstacles to strawberry cultivation, but knowledge of the recovery mechanisms underlying this phenomenon is limited. RESULTS: In this study, transcriptomic profiling of strawberry roots in soil with and without the SA was conducted using RNA-Seq technology to reveal gene expression changes in response to SA treatment. In total, 188 differentially expressed genes (DEGs), including 144 upregulated and 44 downregulated DEGs, were identified. SA treatment resulted in genotype-dependent responses, and the response pattern, including an overall increase in the expression of nutrient transport genes and a decrease in the expression of defense response genes, may be a possible mechanism underlying recovery strategies in strawberry roots after the application of the SA to CC soil. We also found that 9 Hsp genes involved in plant defense pathways were all downregulated in the SA-treated roots. CONCLUSIONS: This research indicated that strawberry plants reallocated defense resources to development when SA treatment alleviated the stress caused by a CC soil environment. The present study provides an opportunity to reveal the fundamental mechanisms of the tradeoff between growth and defense in strawberry.

KIFC1 promotes the proliferation of hepatocellular carcinoma in vitro and in vivo.

Hepatocellular carcinoma (HCC) is a common type of malignant tumor worldwide with a high mortality rate. In the past 20 years, the morbidity rate of HCC has increased. Progress has been made in the clinical diagnosis and therapy for HCC. However, due to the high heterogeneity and metastasis targeted therapy for HCC exhibits great promise, and novel therapeutic targets for HCC are urgently required. Kinesin family member C1 (KIFC1) is a member of the kinesin superfamily of proteins. Previous studies have indicated a potential association between KIFC1 and cancer progression. However, the potential role of KIFC1 in the development of HCC remains unclear. The present study aimed to explore the function of KIFC1 in HCC. Immunohistochemical (IHC) assays were performed to explore the KIF15 expression levels in 74 samples of HCC and corresponding non-tumor tissues. The potential association between KIF15 expression levels and clinical features was analyzed, and the effects of KIF15 on cell proliferation of HCC were detected by colony formation and MTT assays. In addition, the proliferation-related proteins Ki67 and PCNA were detected by western blotting. The possible effects of KIF15 on tumor growth were measured in mice. The results demonstrated that a high expression level of KIFC1 was associated with poor prognosis of HCC. Further results indicated that KIFC1 promoted cell proliferation of HCC in vitro. In addition, knockdown of KIFC1 suppressed tumor formation and growth in mice. Therefore, these results provide a potential therapeutic target for the treatment of HCC.

Sevoflurane post-conditioning alleviates neonatal rat hypoxic-ischemic cerebral injury via Ezh2-regulated autophagy.

Background: When neonatal rats suffer hypoxic-ischemic brain injury (HIBI), autophagy is over-activated in the hippocampus, and inhibition of autophagy provides neuroprotection. The aim of this study was to investigate the possible roles of autophagy and Ezh2-regulated Pten/Akt/mTOR pathway in sevoflurane post-conditioning (SPC)-mediated neuroprotection against HIBI in neonatal rats. Methods: Seven-day-old Sprague-Dawley rats underwent left common artery ligation followed by 2 h hypoxia as described in the Rice-Vannucci model. The roles of autophagy and the Ezh2-regulated Pten/Akt/mTOR signaling pathway in the neuroprotection conferred by SPC were examined by left-side intracerebroventricular injection with the autophagy activator rapamycin and the Ezh2 inhibitor GSK126. Results: SPC was neuroprotective against HIBI through the inhibition of over-activated autophagy in the hippocampus as characterized by the rapamycin-induced reversal of neuronal density, neuronal morphology, cerebral morphology, and the expression of the autophagy markers, LC3B-II and Beclin1. SPC significantly increased the expression of Ezh2, H3K27me3, pAkt, and mTOR and decreased the expression of Pten induced by HI. The Ezh2 inhibitor, GSK126, significantly reversed the SPC-induced changes in expression of H3K27me3, Pten, pAkt, mTOR, LC3B-II, and Beclin1. Ezh2 inhibition also reversed SPC-mediated attenuation of neuronal loss and behavioral improvement in the Morris water maze. Conclusion: These results indicate that SPC inhibits excessive autophagy via the regulation of Pten/Akt/mTOR signaling by Ezh2 to confer neuroprotection against HIBI in neonatal rats.

Exogenous hTERT gene transfected endothelial progenitor cells from bone marrow promoted angiogenesis in ischemic myocardium of rats.

OBJECTIVE: To explore the biological behavior and the revascularizative ability of endothelial progenitor cells (EPCs) transfected with human telomerase reverse transcriptase (hTERT) gene. METHODS: EPCs were isolated from mononuclear cells in bone marrow by using the method of density gradient centrifugation, then cultured with differential velocity adherent method, EPCs were transfected by recombinant plasmid carrying GFP report gene EGFP-hTERT. The EPCs secretion and proliferation ability were detected before and after transfection. The expression of EPCs mRNA were detected by RT-PCR before and after transfection. The new capillaries of infarct area were observed. RESULTS: After transgenesis, the proliferation of EPCs were increased, and the secretion of NO, LDH, iNOS by EPCs were significantly increased compared to the non-transgenesis group. After transplanted the transfected EPCs into the ischemic myocardial of rats, revascularization were increased obviously. CONCLUSION: EPCs maintained the original biological characteristics after transfecting exogenous hTER gene, the proliferation and survival rate were up-regulated significantly, and the revascularization ability of EPCs were significantly strengthen.