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Animal models of COVID-19 facilitate the development of vaccines and antivirals against SARS-CoV-2. The efficacy of antivirals or vaccines may differ in different animal models with varied degrees of disease. Here, we introduce a mouse model expressing human angiotensin-converting enzyme 2 (ACE2). In this model, ACE2 with the human cytokeratin 18 promoter was knocked into the Hipp11 locus of C57BL/6J mouse by CRISPR – Cas9 (K18-hACE2 KI). Upon intranasal inoculation with high (3 × 105 PFU) or low (2.5 × 102 PFU) dose of SARS-CoV-2 wildtype (WT), Delta, Omicron BA.1, or Omicron BA.2 variants, all mice showed obvious infection symptoms, including weight loss, high viral loads in the lung, and interstitial pneumonia. 100% lethality was observed in K18-hACE2 KI mice infected by variants with a delay of endpoint for Delta and BA.1, and a significantly attenuated pathogenicity was observed for BA.2. The pneumonia of infected mice was accompanied by the infiltration of neutrophils and pulmonary fibrosis in the lung. Compared with K18-hACE2 Tg mice and HFH4-hACE2 Tg mice, K18-hACE2 KI mice are more susceptible to SARS-CoV-2. In the antivirals test, REGN10933 and Remdesivir had limited antiviral efficacies in K18-hACE2 KI mice upon the challenge of SARS-CoV-2 infections, while Nirmatrelvir, monoclonal antibody 4G4, and mRNA vaccines potently protected the mice from death. Our results suggest that the K18-hACE2 KI mouse model is lethal and stable for SARS-CoV-2 infection, and is practicable and stringent to antiviral development.

Some plant-associated microorganisms could improve host plants biotic and abiotic stress tolerance. Imperata cylindrica is a dominant pioneer plant in some abandoned mine lands with higher concentrations of heavy metal (HM). To discover the specific microbiome of I. cylindrica in this extreme environment and evaluate its role, the microbiome of I. cylindrica’s seeds and rhizosphere soils from HM heavily contaminated (H) and lightly contaminated (L) sites were studied. It was found that HM-contamination significantly reduced the richness of endophytic bacteria in seeds, but increased the abundance of resistant species, such as Massilia sp. and Duganella sp. Spearman’s rank correlation coefficient analysis showed that both Massilia sp. and Duganella sp. showed a significant positive correlation with Zn concentration, indicating that it may have a strong tolerance to Zn. A comparison of the microbiome of rhizosphere soils (RS) and adjacent bare soils (BS) of site H showed that I. cylindrica colonization significantly increased the diversity of fungi in rhizosphere soil and the abundance of Ascomycota associated with soil nutrient cycling. Spearman’s rank correlation coefficient analysis showed that Ascomycota was positively correlated with the total nitrogen. Combined with the fact that the total nitrogen content of RS was significantly higher than that of BS, we suppose that Ascomycota may enhance the nitrogen fixation of I. cylindrica, thereby promoting its growth in such an extreme environment. In conclusion, the concentration of HM and nutrient contents in the soil significantly affected the microbial community of rhizosphere soils and seeds of I. cylindrica, in turn, the different microbiomes further affected soil HM concentration and nutrient contents. The survival of I. cylindrica in HM severely contaminated environment may mainly be through recruiting more microorganisms that can enhance its nutrition supply.

Abstract Background Pectate lyase (PL, EC 4.2.2.2), as an endo-acting depolymerizing enzyme, cleaves α-1,4-glycosidic linkages in esterified pectin and involves a broad range of cell wall modifications. However, the knowledge concerning the genome-wide analysis of the PL gene family in Fragaria vesca has not been thoroughly elucidated. Results In this study, sixteen PLs members in F. vesca were identified based on a genome-wide investigation. Substantial divergences existed among FvePLs in gene duplication, cis-acting elements, and tissue expression patterns. Four clusters were classified according to phylogenetic analysis. FvePL6, 8 and 13 in cluster II significantly contributed to the significant expansions during evolution by comparing orthologous PL genes from Malus domestica, Solanum lycopersicum, Arabidopsis thaliana, and Fragaria×ananassa. The cis-acting elements implicated in the abscisic acid signaling pathway were abundant in the regions of FvePLs promoters. The RNA-seq data and in situ hybridization revealed that FvePL1, 4, and 7 exhibited maximum expression in fruits at twenty days after pollination, whereas FvePL8 and FvePL13 were preferentially and prominently expressed in mature anthers and pollens. Additionally, the co-expression networks displayed that FvePLs had tight correlations with transcription factors and genes implicated in plant development, abiotic/biotic stresses, ions/Ca2+, and hormones, suggesting the potential roles of FvePLs during strawberry development. Besides, histological observations suggested that FvePL1, 4 and 7 enhanced cell division and expansion of the cortex, thus negatively influencing fruit firmness. Finally, FvePL1-RNAi reduced leaf size, altered petal architectures, disrupted normal pollen development, and rendered partial male sterility. Conclusion These results provide valuable information for characterizing the evolution, expansion, expression patterns and functional analysis, which help to understand the molecular mechanisms of the FvePLs in the development of strawberries.

Fruit prickles are widely distributed on the pericarp and exhibit polymorphic traits at different developmental stages. Although they are multicellular appendages that are well-known for helping plants defend against biotic and abiotic stresses, their origination and molecular mechanism are still less known. Here, we studied the origination and molecular mechanism of fruit prickles in Rosa roxburghii. Using morphological and histological observations, we found that the fruit prickle primordium of R. roxburghii originated from the ground meristem that underwent cell division to form flagelliform prickles, continued to enlarge, and finally lignified to form mature fruit prickles. We amplified a homolog of candidate gene TRANSPARENT TESTA GLABRA1 (TTG1) from R. roxburghii, named RrTTG1. RrTTG1 harbored four conserved WD-repeat domains and was exclusively nuclear-localized. Using qRT-PCR and in situ hybridization, we found that RrTTG1 was constitutively expressed and highly expressed during the initiation and cell expansion phases of fruit prickles. Ectopic expression analysis in Arabidopsis proved that RrTTG1 substantially enhanced the number of trichome and pigmentation production and inhibited root hair formation. Besides, RrTTG1 complemented the phenotypes of the ttg1 mutant in Arabidopsis, thus indicating that RrTTG1 played pleiotropic roles akin to AtTTG1. We demonstrated that the RrTTG1 only interacted with RrEGL3, a homolog of ENHANCER OF GLABRA3 (EGL3), via yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. Briefly, RrTTG1 might positively regulate the initiation of fruit prickle primordium and cell enlargement by forming the RrTTG1-RrEGL3-RrGL1 complex in R. roxburghii. Therefore, our results help characterize the RrTTG1 in R. roxburghii and also elucidate the establishment of the prickles regulatory system in the Rosaceae plants.

Rosa roxburghii Tratt, the most popular fruit that blooms in the southwest of China, has high antioxidant properties and is rich in different flavonoids. However, the regulatory network and critical genes that regulate the flavonoid biosynthesis of R. roxburghii are still unknown. In this study, HPLC analysis revealed that total flavonoids, anthocyanins, and catechin were enriched in mature fruits, flowers, and leaves, respectively. Differentially expressed genes (DEGs) between five organs of R. roxburghii involved in flavonoid metabolism were obtained by transcriptome sequencing. A total of 1130 DEGs were identified, including 166 flavonoid pathway biosynthesis genes, 622 transcription factors (TFs), 301 transporters, and 221 cytochrome P450 proteins. A weighted gene co-expression network analysis (WGCNA) of the DEGs was conducted to construct co-expression networks. Regarding enzymes in the biosynthesis of flavonoids, cytochrome P450 CYP749A22 and CYP72A219 were highlighted in the regulation of total flavonoids of mature fruits. Anthocyanin 3-O-glucosyltransferase and F3′H were the top two critical enzymes for anthocyanin accumulation in flowers. By contrast, caffeic acid 3-O-methyltransferase, 4-coumarate-CoA ligase, and shikimate O-hydroxycinnamoyltransferase were essential for catechin accumulation in leaves. Additionally, we analyzed the eigengene network of the “black” module, which had high correlations with total flavonoids (r = 0.9, p = 5 × 10−6). There were 26 eigengenes in the “black” module, consisting of 6 flavonoid biosynthesis, 14 TFs, and 6 transporters. Among them, the transcription factors RrWRKY45 (DN142829_c1_g5), RrTCP20 (DN146443_c1_g1), and RrERF118 (DN141507_c3_g2) were screened as the hub genes, which significantly correlated with total flavonoids in R. roxburghii. The present biochemical and transcriptomic data provide insights into functional genomics for breeding R. roxburghii with flavonoid accumulation.

Thrombosis is a severe health care issue and one of the leading causes of death globally. Since presently used drugs have a number of limitations, safe and effective thrombolytic agents are still needed. Subtilisin QK, widely used as a component of functional food, presents high direct cross-linked fibrin degradation, without activation of plasminogen. It could be absorbed throughout intestine and infiltrate into all organs with fibrinolytic activity against the pancreatic enzyme and acidic pH mimicking the stomach in a time-dependent manner. Oral intake of rSubtilisin QK also elevated levels of fibrin/fibrinogen degradation products, D-dimer, and tissue plasminogen activator (t-PA) in plasma, and alleviated ear- and tail-thrombosis in κ-carrageenan-induced model. Furthermore, the levels of t-PA were increased in cultured HUVECs stimulated with rSubtilisin QK, while plasminogen activator inhibitor-1 showed the opposite trend simultaneously, suggesting the activation of plasminogen. In conclusion, rSubtilisin QK exerted thrombolytic effects in vivo and may be a potential oral thrombolytic agent.

BackgroundPain management is currently important in neonatal intensive care unit (NICU). The superiority in pain relief of the combined oral sucrose (OS) and nonnutritive sucking (NNS) to other single intervention has not been well established. The administration of sucrose has been considered to potentially induce adverse events, which has been controversial. This study aims to investigate the combined effects and safety in comparison with other single intervention methods, including NNS, OS alone, breast milk and oral glucose.MethodsWe searched databases including Medline (via Pubmed), Embase (via Ovid), web of science, and Cochrane Library for randomized controlled trials from Jan 1, 2000 to Mar 31, 2021. The data were analyzed in the meta-analysis using Review manager Version 5.3. Pain score was the primary outcome in this meta-analysis. The adverse events were assessed qualitatively.ResultsA total of 16 studies were eligible in the meta-analysis. The results demonstrated a significant reduction in pain score in the NNS+OS group compared with NNS alone (SMD = -1.69, 95%CI, -1.69,-0.65) or sucrose alone (SMD = -1.39, 95% CI, -2.21,-0.57) during the painful procedures. When compared NNS+OS with breast milk, no significant difference was detected (SMD = -0.19, 95% CI: -0.5, 0.11).ConclusionThe combined effects of NNS and OS might be superior to other single intervention method. However, the effects might be mild for moderate-to-severe pain.

Carbon dioxide (CO2) capture and conversion provide an alternative approach to synthesis of useful fuels and chemicals. Here, Ye et al. give a comprehensive perspective on the current state of the art and outlook of CO2 catalytic hydrogenation to the synthesis of light olefins, dimethyl ether, liquid fuels, and alcohols.

Kiwifruit is commonly sensitive to waterlogging stress, and grafting onto a waterlogging-tolerant rootstock is an efficient strategy for enhancing the waterlogging tolerance of kiwifruit plants. KR5 (Actinidia valvata) is more tolerant to waterlogging than ‘Hayward’ (A. deliciosa) and is a potential resistant rootstock for kiwifruit production. Here, we focused on evaluating the performance of the waterlogging-sensitive kiwifruit scion cultivar ‘Zhongmi 2′ when grafted onto KR5 (referred to as ZM2/KR5) and Hayward (referred to as ZM2/HWD) rootstocks, respectively, under waterlogging stress. The results showed ‘Zhongmi 2′ performed much better when grafted onto KR5 than when grafted onto ‘Hayward’, exhibiting higher photosynthetic efficiency and reduced reactive oxygen species (ROS) damage. Furthermore, the roots of ZM2/KR5 plants showed greater root activity and energy supply, lower ROS damage, and more stable osmotic adjustment ability than the roots of ZM2/HWD plants under waterlogging stress. In addition, we detected the expression of six key genes involved in the kiwifruit waterlogging response mechanism, and these genes were remarkably induced in the ZM2/KR5 roots but not in the ZM2/HWD roots under waterlogging stress. Moreover, principal component analysis (PCA) further demonstrated the differences in the physiological responses of the ZM2/KR5 and ZM2/HWD plants under waterlogging stress. These results demonstrated that the KR5 rootstock can improve the waterlogging tolerance of grafted kiwi plants by regulating physiological and biochemical metabolism and molecular responses.

Curative therapies for chronic hepatitis B virus (HBV) infection remain a distant goal, and the persistence of stable covalently closed circular DNA (cccDNA) during HBV replication is a key barrier that is hard to break through using the drugs currently approved for HBV treatment. Due to the accuracy, efficiency, and cost-effectiveness of genome editing, CRISPR/Cas technologies are being widely used for gene therapy and in antiviral strategies. Although CRISPR/Cas could possibly clear cccDNA, ensuring its safety is requirement for application. In our study, we analyzed the liver specificity of several promoters and constructed candidate promoters in the CRISPR/Staphylococcus aureus Cas9 (SaCas9) system combined with hepatotropic AAV8 (whereby AAV refers to adeno-associated virus) to verify the efficacy against HBV. The results revealed that the reconstructed CRISPR/SaCas9 system in which the original promoter replaced with a liver-specific promoter could still inhibit HBV replication both in vitro and in vivo. Three functional guide RNAs (gRNAs), T2, T3, and T6, which target the conserved regions of different HBV genotypes, demonstrated consistently better anti-HBV effects with different liver-specific promoters. Moreover, the three gRNAs inhibited the replication of HBV genotypes A, B, and C to varying degrees. Under the action of the EnhII-Pa1AT promoter and AAV8, the expression of SaCas9 was further decreased in other organs or tissues in comparison to liver. These results are helpful for clinical applications in liver by ensuring the effects of the CRISPR/Cas9 system remain restricted to liver and, thereby, reducing the probability of undesired and harmful effects through nonspecific targeting in other organs.

Hepatitis B virus is an enveloped DNA virus, that infects more than three hundred and sixty million people worldwide and leads to severe chronic liver diseases. Interferon-alpha inducible protein 6 (IFI6) is an IFN-stimulated gene (ISG) whose expression is highly regulated by the stimulation of type I IFN-alpha that restricts various kinds of virus infections by targeting different stages of the viral life cycle. This study aims to investigate the antiviral activity of IFI6 against HBV replication and gene expression. The IFI6 was highly induced by the stimulation of IFN-α in hepatoma cells. The overexpression of IFI6 inhibited while knockdown of IFI6 elevated replication and gene expression of HBV in HepG2 cells. Further study determined that IFI6 inhibited HBV replication by reducing EnhII/Cp of the HBV without affecting liver enriched transcription factors that have significant importance in regulating HBV enhancer activity. Furthermore, deletion mutation of EnhII/Cp and CHIP analysis revealed 100 bps (1715-1815 nt) putative sites involved in IFI6 mediated inhibition of HBV. Detailed analysis with EMSA demonstrated that 1715-1770 nt of EnhII/Cp was specifically involved in binding with IFI6 and restricted EnhII/Cp promoter activity. Moreover, IFI6 was localized mainly inside the nucleus to involve in the anti-HBV activity of IFI6. In vivo analysis based on the hydrodynamic injection of IFI6 expression plasmid along with HBV revealed significant inhibition of HBV DNA replication and gene expression. Overall, our results suggested a novel mechanism of IFI6 mediated HBV regulation that could develop potential therapeutics for efficient HBV infection treatment.

Despite the availability of effective vaccines, hepatitis B virus (HBV) is still a major health issue, and approximately 350 million people have been chronically infected with HBV throughout the world. Interferons (IFNs) are the key molecules in the innate immune response that restrict several kinds of viral infections via the induction of hundreds of IFN-stimulated genes (ISGs). The objective of this study was to confirm if interferon alpha-inducible protein 27 (IFI27) as an ISG could inhibit HBV gene expression and DNA replication both in cell culture and in a mouse model. In human hepatoma cells, IFI27 was highly induced by the stimulation of IFN-alpha (IFN-α), and it potentiated the anti-HBV activity. The overexpression of IFI27 inhibited, while its silencing enhanced the HBV replication in HepG2 cell. However, the knocking out of IFI27 in HepG2 cells robustly increases the formation of viral DNA, RNA, and proteins. Detailed mechanistic analysis of the HBV genome showed that a sequence [nucleotide (nt) 1715–1815] of the EnhII/Cp promoter was solely responsible for viral inhibition. Similarly, the hydrodynamic injection of IFI27 expression constructs along with the HBV genome into mice resulted in a significant reduction in viral gene expression and DNA replication. In summary, our studies suggested that IFI27 contributed a vital role in HBV gene expression and replication and IFI27 may be a potential antiviral agent for the treatment of HBV.

Boron (B) deficiency inhibits and disturbs root growth and development by interacting with auxin (indole-3-acetic acid, IAA). However, the underlying mechanism of this interaction is still poorly understood. This study found that plants in a long-term boron deprivation treatment (∼0.25 µg L−1) had inhibited elongation of trifoliate orange roots, enlarged root tips and severe necrosis as well as a significant decrease in soluble boron and IAA content in seedling root tips. The results of a short-term boron deprivation treatment showed that a significant decrease in soluble boron and IAA content occurred after 3 hours of treatment (HOT) and 1 day of treatment (DOT), respectively. Moreover, the expression of IAA synthetic genes (TAA1, TAR2, YUC3 and YUC8) was strongly induced as early as 3 HOT and was then significantly reduced. The expression of rootward IAA transport genes (AUX1, PIN1 and PIN4) decreased significantly in the boron deprivation treatment, but the expression levels of shootward IAA transport genes (LAX1, ABCB1 and PIN3) were significantly increased. Taken together, the increase in IAA content before 1 DOT may be due to increased IAA synthesis caused by the induction of TAA1, TAR2, YUC3 and YUC8 expression; the subsequent decrease and the significantly lower final IAA content compared to the +B treatment (0.25 mg L−1 B) may be due to the reduced expression of IAA synthetic genes and rootward IAA transport genes and the increased expression of shootward IAA transport genes. Abbreviations: DAT: days after treatment; DOT: day of treatment; FW: fresh weight; HOT: hour of treatment; isB: insoluble boron; LC: liquid chromatography; LSD: least-significant difference; MS: mass spectrometry; PAT: polar auxin transport; qRT-PCR: quantitative real-time polymerase chain reaction; sB: soluble boron

Reducing emissions from deforestation and forest degradation (REDD+) is viewed as an effective way to mitigate climate change by compensating stewards of forested areas for minimizing forestland conversion and protecting forest services. Opportunity costs assess the cost of foregone opportunity when preserving the forest instead of investing in an alternative activity or resource use. This paper questions the calculation method of opportunity costs using averaged economic benefits and co-benefits of different land-use transitions. We propose a nested approach to land-use transitions at the interface between landscapes and livelihoods and assessing a wide range of potential socio-ecological costs and benefits. Combining household surveys and focus groups with participatory mapping, we applied the approach in villages of Laos, Vietnam and China positioned along a broad transition trajectory from subsistence shifting cultivation to intensive commercial agriculture. By looking beyond the economics of land use, we highlight important linkages between land-use changes and livelihood differentiation, vulnerability and inequalities. Our results show the importance of addressing the impacts of land-use transitions on a wide range of potential ecological and socioeconomic costs and benefits at multiple levels.

Biodiversity conservation is a required co-benefit of REDD+. Biodiversity monitoring is therefore needed, yet in most areas it will be constrained by limitations in the available human professional and financial resources. REDD+ programs that use forest plots for biomass monitoring may be able to take advantage of the same data for detecting changes in the tree diversity, using the richness and abundance of canopy trees as a proxy for biodiversity. If local community members are already assessing the above-ground biomass in a representative network of forest vegetation plots, it may require minimal further effort to collect data on the diversity of trees. We compare community members and trained scientists' data on tree diversity in permanent vegetation plots in montane forest in Yunnan, China. We show that local community members here can collect tree diversity data of comparable quality to trained botanists, at one third the cost. Without access to herbaria, identification guides or the Internet, community members could provide the ethno-taxonomical names for 95% of 1071 trees in 60 vegetation plots. Moreover, we show that the community-led survey spent 89% of the expenses at village level as opposed to 23% of funds in the monitoring by botanists. In participatory REDD+ programs in areas where community members demonstrate great knowledge of forest trees, community-based collection of tree diversity data can be a cost-effective approach for obtaining tree diversity information.

In this paper, the Graphics Processor Unit (GPU) is adopted to accelerate the codes of solving incompressible Navier-Stokes equations with two fully different numerical schemes: spectral method and finite difference method. Compared with the codes on CPU, the performance of the codes on GPU is much better, especially when the resolution increases. For the resolution of 2048 × 2048, the acceleration of spectral method reaches 14.45 times. 14.15 times acceleration is achieved when finite difference method in the resolution of 600 × 2400 is applied. We also try to combine MPI (Message Passing Interface) and CUDA (Compute Unified Device Architecture) in the spectral solver to accomplish larger simulations. Due to the inevitable frequent data transfers between Host and Device, the speedup is not so ideal compared with that of the single node, and only 1.82 times acceleration is obtained for the resolution of 4096 × 4096.

Although the high nonlinearity, strontium tetraborate crystal SrB4O7 is angular non-phasematched in UV SHG process due to its low birefringence. In this Letter, we revealed that its birefringence can be significantly enhanced by uniaxial strain based on the first principles computations. The birefringence is thirteen and sixteen times larger than those of unstrained crystal at -10% a-axial compressive and 10% a-axial tensile strain, respectively. The compressive strain also effectively improve the static second-order coefficients and shift the optical absorption edge towards the UV side, which would shed light on the modulations of UV/VUV nonlinear optical crystals by directionally external stress.

Will community monitoring assist in delivering just and equitable REDD+? We assessed whether local communities can effectively estimate carbon stocks in some of the world's most carbon rich forests, using simple field protocols, and we reviewed whether community monitoring exists in current REDD+ pilots. We obtained similar results for forest carbon when measured by communities and professional foresters in 289 vegetation plots in Southeast Asia. Most REDD+ monitoring schemes, however, contain no community involvement. To close the gulf between United Nations Framework Convention on Climate Change texts on involving communities and field implementation realities, we propose greater embedding of community monitoring within national REDD+ pilot schemes, which we argue will lead to a more just REDD+.

ABSTRACT Background The relationship between sarcopenia and the prognosis of patients with tumours who received radio‐ and/or chemotherapy still needs to be determined. In this study, we aim to investigate the relationship between sarcopenia and adverse effects and mortality in patients with tumours that received radio‐ and/or chemotherapy, stratified by study design, tumour category, the method sarcopenia assessed, treatment options, study location and among other factors. Methods PubMed, Web of Science and Embase were searched from inception to 15 August 2024, without language restrictions and with a manual search of references for additional articles retrieval. Cohort studies of ≥ 100 patients with tumours that evaluated the association between sarcopenia or muscle mass and the adverse effects or overall survival induced by radio‐ and/or chemotherapy were included. Results Thirty‐nine studies were included, involving 8966 patients with tumours, including 3383 patients with sarcopenia. The pooled prevalence of sarcopenia in patients with tumours was 0.42 (95% CI 0.36–0.48, p