USP1/UAF1-Stabilized METTL3 Promotes Reactive Astrogliosis and Improves Functional Recovery after Spinal Cord Injury through m6A Modification of YAP1 mRNA.

RNA N6-methyladenosine (m6A) modification is involved in diverse biological processes. However, its role in spinal cord injury (SCI) is poorly understood. The m6A level increases in injured spinal cord, and METTL3, which is the core subunit of methyltransferase complex, is upregulated in reactive astrocytes and further stabilized by the USP1/UAF1 complex after SCI. The USP1/UAF1 complex specifically binds to and subsequently removes K48-linked ubiquitination of the METTL3 protein to maintain its stability after SCI. Moreover, conditional knockout of astrocytic METTL3 in both sexes of mice significantly suppressed reactive astrogliosis after SCI, thus resulting in widespread infiltration of inflammatory cells, aggravated neuronal loss, hampered axonal regeneration, and impaired functional recovery. Mechanistically, the YAP1 transcript was identified as a potential target of METTL3 in astrocytes. METTL3 could selectively methylate the 3'-UTR region of the YAP1 transcript, which subsequently maintains its stability in an IGF2BP2-dependent manner. In vivo, YAP1 overexpression by adeno-associated virus injection remarkably contributed to reactive astrogliosis and partly reversed the detrimental effects of METTL3 knockout on functional recovery after SCI. Furthermore, we found that the methyltransferase activity of METTL3 plays an essential role in reactive astrogliosis and motor repair, whereas METTL3 mutant without methyltransferase function failed to promote functional recovery after SCI. Our study reveals the previously unreported role of METTL3-mediated m6A modification in SCI and might provide a potential therapy for SCI.SIGNIFICANCE STATEMENT Spinal cord injury is a devastating trauma of the CNS involving motor and sensory impairments. However, epigenetic modification in spinal cord injury is still unclear. Here, we propose an m6A regulation effect of astrocytic METTL3 following spinal cord injury, and we further characterize its underlying mechanism, which might provide promising strategies for spinal cord injury treatment.

Inhibitor AN3661 reveals biological functions of Arabidopsis CLEAVAGE and POLYADENYLATION SPECIFICITY FACTOR 73.

Cleavage and polyadenylation specificity factor (CPSF) is a protein complex that plays an essential biochemical role in mRNA 3'-end formation, including poly(A) signal recognition and cleavage at the poly(A) site. However, its biological functions at the organismal level are mostly unknown in multicellular eukaryotes. The study of plant CPSF73 has been hampered by the lethality of Arabidopsis (Arabidopsis thaliana) homozygous mutants of AtCPSF73-I and AtCPSF73-II. Here, we used poly(A) tag sequencing to investigate the roles of AtCPSF73-I and AtCPSF73-II in Arabidopsis treated with AN3661, an antimalarial drug with specificity for parasite CPSF73 that is homologous to plant CPSF73. Direct seed germination on an AN3661-containing medium was lethal; however, 7-d-old seedlings treated with AN3661 survived. AN3661 targeted AtCPSF73-I and AtCPSF73-II, inhibiting growth through coordinating gene expression and poly(A) site choice. Functional enrichment analysis revealed that the accumulation of ethylene and auxin jointly inhibited primary root growth. AN3661 affected poly(A) signal recognition, resulted in lower U-rich signal usage, caused transcriptional readthrough, and increased the distal poly(A) site usage. Many microRNA targets were found in the 3' untranslated region lengthened transcripts; these miRNAs may indirectly regulate the expression of these targets. Overall, this work demonstrates that AtCPSF73 plays important part in co-transcriptional regulation, affecting growth, and development in Arabidopsis.

Does phytoextraction with Sedum plumbizincicola increase cadmium leaching from polluted agricultural soil?

Sedum plumbizincicola is a cadmium (Cd) and zinc hyperaccumulator that can activate Cd by rhizosphere acidification. However, there is little understanding of the Cd leaching risk from polluted soil during phytoextraction process. Here, pot and column experiments were conducted to monitor soil Cd leaching characteristics under different rainfall simulation conditions during S. plumbizincicola phytoextraction. Soil Cd leaching increased significantly with increasing simulated rainfall intensity. Compared with normal rainfall (NR), weak rainfall (WR) resulted in a 34.3% decrease in Cd uptake by S. plumbizincicola and also led to a 68.7% decline in Cd leaching. In contrast, Cd leaching under heavy rainfall (HR) was 2.12 times that of NR in the presence of S. plumbizincicola. After two successive growing periods, phytoextraction resulted in a 53.5-66.4% decline in the amount of soil Cd leached compared with controls in which S. plumbizincicola was absent. Even compared with maize cropping as a control, S. plumbizincicola did not instigate a significant increase in Cd leaching. The contribution of Cd leaching loss to the decline in soil total Cd concentration was negligible after phytoextraction in the pot experiment. Overall, the results contribute to our understanding of soil Cd leaching risk by phytoextraction with S. plumbizincicola.

Repeated phytoextraction by hyperaccumulator Sedum plumbizincicola is an important remediation technology to remove Cd from contaminated soils. At the same time, Sedum plumbizincicola can also activate soil Cd by rhizosphere acidification. However, studies on the leaching risk of soil activated Cd during the phytoextraction process are very few. This study looked at the effects of Sedum plumbizincicola growth on soil Cd leaching with the changes in rainfall simulation and plant type. Results showed that repeated phytoextraction with Sedum plumbizincicola did not increase Cd leaching from contaminated soil.

Chromosome painting reveals inter-chromosomal rearrangements and evolution of subgenome D of wheat.

Aegilops species represent the most important gene pool for breeding bread wheat (Triticum aestivum). Thus, understanding the genome evolution, including chromosomal structural rearrangements and syntenic relationships among Aegilops species or between Aegilops and wheat, is important for both basic genome research and practical breeding applications. In the present study, we attempted to develop subgenome D-specific fluorescence in situ hybridization (FISH) probes by selecting D-specific oligonucleotides based on the reference genome of Chinese Spring. The oligo-based chromosome painting probes consisted of approximately 26 000 oligos per chromosome and their specificity was confirmed in both diploid and polyploid species containing the D subgenome. Two previously reported translocations involving two D chromosomes have been confirmed in wheat varieties and their derived lines. We demonstrate that the oligo painting probes can be used not only to identify the translocations involving D subgenome chromosomes, but also to determine the precise positions of chromosomal breakpoints. Chromosome painting of 56 accessions of Ae. tauschii from different origins led us to identify two novel translocations: a reciprocal 3D-7D translocation in two accessions and a complex 4D-5D-7D translocation in one accession. Painting probes were also used to analyze chromosomes from more diverse Aegilops species. These probes produced FISH signals in four different genomes. Chromosome rearrangements were identified in Aegilops umbellulata, Aegilops markgrafii, and Aegilops uniaristata, thus providing syntenic information that will be valuable for the application of these wild species in wheat breeding.

Zinc Supply Affects Cadmium Uptake and Translocation in the Hyperaccumulator Sedum Plumbizincicola as Evidenced by Isotope Fractionation.

This study employs stable isotope analysis to investigate the mechanisms of cadmium (Cd) and zinc (Zn) interaction in the metal hyperaccumulating plant species Sedum plumbizincicola. To this end, the Cd and Zn isotope compositions of root, stem, leaf, and xylem sap samples were determined during metal uptake and translocation at different Cd and Zn concentrations. The enrichment of light isotopes of both elements in plants during uptake was less pronounced at low metal supply levels, likely reflecting the switch from a low-affinity to a high-affinity transport system at lower levels of external metal supply. The lower δ114/110Cd values of xylem sap when treated with a metabolic inhibitor decreasing the active Cd uptake further supports the preference of heavier Cd isotopes during high-affinity transport. The Δ66Znplant-initial solution or Δ66Znplant-final solution values were similar at different Cd concentrations, indicating negligible interaction of Cd in the Zn uptake process. However, decreasing Zn supply levels significantly increased the enrichment of light Cd isotopes in plants (Δ114/110Cd = -0.08‰) in low-Cd treatments but reduced the enrichment of light Cd isotopes in plants (Δ114/110Cd = 0.08‰) under high Cd conditions. A systematic enrichment of heavy Cd and light Zn isotopes was found in root-to-shoot translocation of the metals. The Cd concentrations of the growth solutions thereby had no significant impact on Zn isotope fractionation during root-to-shoot translocation. However, the Δ114/110Cdtranslocation values hint at possible competition between Cd and Zn for transporters during root-to-shoot transfer and this may impact the transport pathway of Cd. The stable isotope data demonstrate that the interactions between the two metals influenced the uptake and transport mechanisms of Cd in S. plumbizincicola but had little effect on those of Zn.

Aberrant Expressions of PSMD14 in Tumor Tissue are the Potential Prognostic Biomarkers for Hepatocellular Carcinoma after Curative Resection.

Introduction: Hepatocellular carcinoma (HCC) has a high mortality rate, with curative resection being the primary treatment. However, HCC patients have a large possibility of recurrence within 5 years after curative resection. Methods: Thus, identifying biomarkers to predict recurrence is crucial. In our study, we analyzed data from CCLE, GEO, and TCGA, identifying eight oncogenes associated with HCC. Subsequently, the expression of 8 genes was tested in 5 cases of tumor tissues and the adjacent non-tumor tissues. Then ATP6AP1, PSMD14 and HSP90AB1 were selected to verify the expression in 63 cases of tumor tissues and the adjacent non-tumor tissues. The results showed that ATP6AP1, PSMD14, HSP90AB1 were generally highly expressed in tumor tissues. A five-year follow-up of the 63 clinical cases, combined with Kaplan-Meier Plotter's relapse-free survival (RFS) analysis, found a significant correlation between PSMD14 expression and recurrence in HCC patients. Subsequently, we analyzed the PSMD14 mutations and found that the PSMD14 gene mutations can lead to a shorter disease-free survival time for HCC patients. Results: The results of enrichment analysis indicated that the differentially expressed genes related to PSMD14 are mainly enriched in the signal release pathway. Conclusion: In conclusion, our research showed that PSMD14 might be related to recurrence in HCC patients, and the expression of PSMD14 in tumor tissue might be a potential prognostic biomarker after tumor resection in HCC patients.

Potential mobilization of cadmium and zinc in soils spiked with smithsonite and sphalerite under different water management regimes.

Particulate cadmium (Cd) and zinc (Zn) are ubiquitous in agricultural soils of Pb-Zn mining regions. Water management serves as an important agronomic measure altering the bioavailability of Zn and Cd in soils, but how this affects particulate Cd and Zn and the underlying mechanisms remain largely unknown. Microcosm soil incubation combined with spectroscopic and microscopic characterization was conducted. During a two-year-long incubation period we observed that the concentrations of soil CaCl2-extractable Zn and Cd increased 3-10 times in sphalerite-spiked soils and 1-2 times in smithsonite-spiked soils under periodic flooding conditions due to the long-term dissolution of sphalerite (SP) and smithsonite (SM). However, the increase in the concentration of CaCl2-extractable metals (Zn: from 0.607 mg kg-1 to 1.051 mg kg-1 and Cd: from 0.047 mg kg-1 to 0.119 mg kg-1) was found only in SP-treatment under continuous flooding conditions, indicating the mobilization of metals. Ultrafiltration analysis shows that the nanoparticulate fraction of Zn and Cd in soil pore water increased 5 and 7 times in SP-treatments under continuous flooding conditions, suggesting the increment of metal pools in soil pore water. HRTEM-EDX-SAED further reveals that these nanoparticles were mainly crystalline ZnS and Zn-bearing sulfate nanoparticles in the SP-treatment and amorphous ZnCO3 and ZnS nanoparticles in the SM-treatment. Therefore, the formation of the stable crystalline Zn-bearing nanoparticles in the SP-treatment may explain the elevation of the concentration of soil CaCl2-extractable Zn and Cd under continuous flooding. The potential mobility of particulate metals should therefore be expected in scenarios of continuous flooding such as paddy soils and wetland systems.

Accessing Highly Efficient Photothermal Conversion with Stable Open-Shell Aromatic Nitric Acid Radicals.

It is very challenging to prepare stable radicals as they are usually thermodynamically or kinetically unstable in air. Herein, a series of star-shaped aromatic nitric acid radicals were prepared via facile demethylation and consequent oxidation. As phenol radicals without steric hindrance group protection, they exhibit high electrochemical and thermal stability due to their rich resonance structures including closed-shell nitro-like and open-shell nitroxide structure with unpaired electrons delocalized in conjugated backbones. Among them, TPA-TPA-O6 powder exhibited extremely wide absorption from 300 to 2000 nm covering the whole solar spectral irradiance, high photothermal conversion efficiency, and negligible photobleaching effect in seawater desalination. Under the irradiation of one sunlight, the water evaporation efficiency of TPA-TPA-O6 is recorded to be as high as 89.41 % and the water evaporation rate is 1.293 kg m-2 h-1 , which represents the top performance in pure organic small molecule photothermal materials.

Development and application of oligonucleotide-based chromosome painting for chromosome 4D of Triticum aestivum L.

Chromosome painting is a useful technique for distinguishing specific chromosomes (fragments), elucidating the genetic relationships of different genomes or chromosomes, and identifying chromosomal rearrangements. The development of chromosome- or genome-specific probes is fundamental for chromosome painting. The possibility for developing such probes specifically painting homoeologous chromosomes in allopolyploid species has been questioned since that chromosomes belonging to the same homoeologous group share highly conserved sequences. In the present study, we attempted to construct a wheat chromosome 4D-specific oligo probe library by selecting 4D-specific sequences in reference genome of common wheat cv. Chinese Spring (CS, 2n = 6x = 42, AABBDD). The synthesized library contains 27,392 oligos. Oligo painting using the probe library confirmed its specificity, shown by that only chromosome 4D could be painted in three wheat genotypes and CS nulli-tetrasomic line N4AT4D. Oligo painting was successfully used to define the 4D breakpoints in CS deletion lines involving 4D and two wheat-Haynaldia villosa 4D-4V translocation lines. Thirteen wheat relatives and a Triticum durum-H. villosa amphiploid were used for oligo painting. Except the 4D in two Aegilops tauschii accessions, the 4M in Ae. comosa and 4U in Ae. umbellulata could be painted. In tetraploid Ae. ventricosa, both 4D and 4M could be painted; however, the signal intensity of 4M was less compared with 4D. No painted chromosome was observed for the other alien species. This indicated that the relationship among D/M/U was closer than that among D/A/B as well as D with genomes H/R/Ss/Sc/Y/P/N/J. Our successful development of 4D-specific oligo probe library may serve as a model for developing oligo probes specific for other homoeologous chromosomes.

A Eu(III)-based Metal Organic Framework: Selective Sensing of Picric Acid and Nursing Application Values On the Cerebral Edema Induced by Cerebral Hemorrhage Via Reducing the Coagulation Factor II Activity.

A new three-dimensional lanthanide metal-organic framework (Ln-MOF), [Eu4(L)4(H2O)8]·10H2O (1, H3L = biphenyl-3'-nitro-3,4',5-tricarboxylic acid), has been constructed via solvothermal technology and its framework has been detected by the single-crystal X-ray diffraction and elemental analyses. Complex 1 with typical emission of Eu3+ ion represents dramatic luminescence quenching affect for picric acid (PA) and the linear Stern-Volmer plot was surveyed in the consistence, ranging from 0.05 to 0.15 mM (Ksv = 98,074 M- 1). Its therapeutic effect of the compound on the cerebral edema caused by cerebral hemorrhage was estimated and the mechanism was explored. Possible binding interactions have been investigated by molecular docking simulations, from which the binding interactions are identified and the carboxyl oxygens are responsible for those identified interactions.

Bmi-1 determines the stemness of renal stem or progenitor cells.

Renal stem or progenitor cells (RSCs), labeled with CD24 and CD133, play an important role during the repair of renal injury. Bmi-1 is a critical factor in regulating stemness of adult stem cells or progenitor cells. To investigate whether Bmi-1 determines the stemness of RSCs by inhibiting p16 and p53, and/or maintaining redox balance, RSCs were isolated, cultured and analyzed for stemness characterizations. In RSCs from Bmi-1-deficient (Bmi-1-/-) mice and wild type (WT) littermates, self-renewal, stemness, and expressions of molecules for regulating redox balance and cell cycle progression were compared. Self-renewal of RSCs from Bmi-1 and p16 double-knockout (Bmi-1-/-p16-/-), Bmi-1 and p53 double-knockout (Bmi-1-/-p53-/-) and N-acetylcysteine (NAC)-treated Bmi-1-/- mice were further analyzed for amelioration. Human renal proximal tubular epithelial cells (HK2) were also used for signaling analysis. Our results showed that third-passage RSCs from WT mice had good stemness; Bmi-1 deficiency led to the decreased stemness, and the increased apoptosis for RSCs; NAC treatment or p16/p53 deletion ameliorated the decreased self-renewal of RSCs in Bmi-1 deficiency mice by maintaining redox balance or inhibiting cell cycle arrest respectively; Oxidative stress (OS) could negatively feedback regulate the mRNA expressions of Bmi-1, p16 and p53. In conclusion, Bmi-1 determined the stemness of RSCs through maintaining redox balance and preventing cell cycle arrest. Thus, Bmi-1 signaling molecules would be novel therapeutic targets for maintaining RSCs and hampering the progression of kidney diseases to prevent renal failure.

Cadmium Isotopic Fractionation in the Soil-Plant System during Repeated Phytoextraction with a Cadmium Hyperaccumulating Plant Species.

Analysis of stable metal isotopes can provide important information on biogeochemical processes in the soil-plant system. Here, we conducted a repeated phytoextraction experiment using the cadmium (Cd) hyperaccumulator Sedum plumbizincicola X. H. Guo et S. B. Zhou ex L. H. Wu (Crassulaceae) in four different Cd-contaminated agricultural soils over five consecutive crops. Isotope composition of Cd was determined in the four soils before and after the fifth crop, in the plant shoots harvested in all soils in the first crop, and in the NH4OAc extracts of two contrasting soils with large differences in soil pH (5.73 and 7.32) and clay content (20.4 and 31.3%) before and after repeated phytoextraction. Before phytoextraction NH4OAc-extractable Cd showed a slight but significant negative isotope fractionation or no fractionation compared with total Cd (Δ114/110Cdextract-soil = -0.15 ± 0.05 (mean ± standard error) and 0.01 ± 0.01‰), and the extent of fractionation varied with soil pH and clay content. S. plumbizincicola preferentially took up heavy Cd from soils (Δ114/110Cdshoot-soil = 0.02-0.14‰), and heavy isotopes were significantly depleted in two soils after repeated phytoextraction (Δ114/110Cdsoil:P5-soil:P0 = -0.15 ± 0.02 and -0.12 ± 0.01‰). This provides evidence for the existence of specific Cd transporters in S. plumbizincicola, leading to positive isotope fractionation during uptake. After phytoextraction by five sequential crops, the NH4OAc-extractable Cd pool was significantly enriched in heavy isotopes (Δ114/110Cdextract:P5-extract:P0 = 0.07 ± 0.02 and 0.18 ± 0.05‰) despite the preferential uptake of heavy isotopes, indicating the occurrence of root-induced Cd mobilization in soils, which is supposed to favor heavy Cd in the organo-complexes with root exudates. Our results demonstrate that Cd is taken up by S. plumbizincicola via specific transporters, partly after active mobilization from the more strongly bound soil pool such as iron/manganese (hydr)oxide-bound Cd during repeated phytoextraction. This renders S. plumbizincicola a suitable plant for large-scale field phytoremediation.

Differences in phytoextraction by the cadmium and zinc hyperaccumulator Sedum plumbizincicola in greenhouse, polytunnel and field conditions.

Differences in growth conditions in the glasshouse and in the field may affect the consistency of phytoextraction results. Two crops of the hyperaccumulator Sedum plumbizincicola were grown in six contrasting soils in pot experiments under three different sets of growth conditions (glasshouse, polytunnel and field) to compare the phytoextraction of cadmium (Cd) and zinc (Zn). The total shoot biomass of two crops in the glasshouse was significantly smaller than in the polytunnel or field. However, in general there were no significant differences in total shoot metal uptake of two crops per pot among three sets of growth conditions. And greater decreases in soil metal than plant uptake in the polytunnel and field in an acid soil indicate high leaching losses of soil metals in the polytunnel and field, and this was confirmed by analysis of metal concentrations in soil profiles. This brings into question on the validity of estimating the practical applicability of phytoextraction based only on plant metal uptake in glasshouse conditions. It is advisable to examine leaching losses in acid soils in the field when estimating the duration of phytoextraction.

Integration of Terrestrial Laser Scanning and NURBS Modeling for the Deformation Monitoring of an Earth-Rock Dam.

A complete picture of the deformation characteristics (distribution and evolution) of the geotechnical infrastructures serves as superior information for understanding their potential instability mechanism. How to monitor more completely and accurately the deformation of these infrastructures (either artificial or natural) in the field expediently and roundly remains a scientific topic. The conventional deformation monitoring methods are mostly carried out at a limited number of discrete points and cannot acquire the deformation data of the whole structure. In this paper, a new monitoring methodology of dam deformation and associated results interpretation is presented by taking the advantages of the terrestrial laser scanning (TLS), which, in contrast with most of the conventional methods, is capable of capturing the geometric information at a huge amount of points over an object in a relatively fast manner. By employing the non-uniform rational B-splines (NURBS) technology, the high spatial resolution models of the monitored geotechnical objects can be created with sufficient accuracy based on these point cloud data obtained from application of the TLS. Finally, the characteristics of deformation, to which the geotechnical infrastructures have been subjected, are interpreted more completely according to the models created based on a series of consecutive monitoring exercises at different times. The present methodology is applied to the Changheba earth-rock dam, which allows the visualization of deformation over the entire dam during different periods. Results from analysis of the surface deformation distribution show that the surface deformations in the middle are generally larger than those on both sides near the bank, and the deformations increase with the increase of the elevations. The results from the present application highlight that the adhibition of the TLS and NURBS technology permits a better understanding of deformation behavior of geotechnical objects of large size in the field.

Percutaneous kyphoplasty in the treatment of Kümmell disease in lumbar scoliosis: A case report.

BACKGROUND: Due to mechanical imbalance in the spine, elderly scoliosis patients tend to develop vertebral fracture nonunion, i.e., Kümmell disease, when osteoporotic vertebral compression fractures occur. However, accompanying vertebral rotational deformities make surgical procedures challenging risky. Such patients are usually compelled to undergo conservative treatment and there are very few reports on minimally invasive surgeries for them. We first-time report a patient with Kümmell disease and lumbar scoliosis treated with percutaneous kyphoplasty (PKP) under O-arm guidance. CASE SUMMARY: An 89-year-old female was admitted to the hospital due to delayed low back pain after a fall. She was diagnosed with Kümmell disease based on physical and radiologic examinations. The patient experienced severe scoliosis and subsequently underwent O-arm-guided kyphoplasty, resulting in a significant alleviation of low back pain. CONCLUSION: PKP has good efficacy in treating Kümmell disease. However, surgical risks are elevated in scoliosis patients with Kümmell disease due to the abnormal anatomical structure of the spine. O-arm assisted operations play a crucial role in decreasing surgical risks.

Sources apportionments of heavy metal(loid)s in the farmland soils close to industrial parks: Integrated application of positive matrix factorization (PMF) and cadmium isotopic fractionation.

Understanding the source identification and distribution of heavy metal(loid)s in soil is essential for risk management. The sources of heavy metal(loid)s in farmland soil, especially in areas with rapid economic development, were complicated and need to be explored urgently. This study combined geographic information system (GIS) mapping, positive matrix factorization (PMF) model and cadmium (Cd) isotope fingerprinting methods to identify heavy metal(loid) sources in a typical town in the economically developed Yangtze River Delta region of China. Cd, As, Cu, Zn, Pb, Ni and Co in different samples were detected. The results showed that Cd was the most severely contaminated element, with an exceedance rate of 78.0 %. GIS mapping results indicated that the hotspot area was located in the northeastern area with prolonged operational histories of electroplating and non-ferrous metal smelting industries. The PMF model analysis also identified emissions from smelting and electroplating enterprises as the main sources of Cd in the soil, counted for 49.28 %, followed by traffic (25.66 %) and agricultural (25.06 %) sources. Through further isotopic analysis, it was found that in soil samples near the industrial park, the contribution of electroplating and non-ferrous metal smelting enterprises to cadmium pollution was significantly higher than other regions. The integrated use of various methodologies allows for precise analysis of sources and input pathways, offering valuable insights for future pollution control and soil remediation endeavors.

Phosphatidic acid-enabled MKL1 contributes to liver regeneration: Translational implication in liver failure.

Liver regeneration following injury aids the restoration of liver mass and the recovery of liver function. In the present study we investigated the contribution of megakaryocytic leukemia 1 (MKL1), a transcriptional modulator, to liver regeneration. We report that both MKL1 expression and its nuclear translocation correlated with hepatocyte proliferation in cell and animal models of liver regeneration and in liver failure patients. Mice with MKL1 deletion exhibited defective regenerative response in the liver. Transcriptomic analysis revealed that MKL1 interacted with E2F1 to program pro-regenerative transcription. MAPKAPK2 mediated phosphorylation primed MKL1 for its interaction with E2F1. Of interest, phospholipase d2 promoted MKL1 nuclear accumulation and liver regeneration by catalyzing production of phosphatidic acid (PA). PA administration stimulated hepatocyte proliferation and enhanced survival in a MKL1-dependent manner in a pre-clinical model of liver failure. Finally, PA levels was detected to be positively correlated with expression of pro-regenerative genes and inversely correlated with liver injury in liver failure patients. In conclusion, our data reveal a novel mechanism whereby MKL1 contributes to liver regeneration. Screening for small-molecule compounds boosting MKL1 activity may be considered as a reasonable approach to treat acute liver failure.

Differences in the activities of six soil enzymes in response to cadmium contamination of paddy soils in high geological background areas.

East Yunnan province in southwest China is a region with elevated natural abundance (high geological background levels) of Cd due to high metal (loid) contents in the soils. Enzyme activities are useful indicators of metal (loid) toxicity in contaminated soils and whether Cd inhibits enzyme activities in paddy soils in high geological background areas is of considerable public concern. A pot experiment combined with field investigation was conducted to assess the effects of Cd on six soil enzymes that are essential to the cycling of C, N, and P in soils. Inhibitory effects of Cd fractions on enzyme activities were assessed using ecological dose-response models. The impact of soil properties on the inhibition of sensitive soil enzymes by Cd were assessed using linear and structural equation models. Cadmium was enriched in the paddy soils with 72.2 % of soil samples from high geological background areas exceeding the Chinese threshold values (GB 15618-2018) of Cd. Enzyme responses to Cd contamination varied markedly with a negative response by catalase but a positive response by invertase. Urease, ß-glucosidase, and alkaline phosphatase activities were stimulated at low Cd concentrations and inhibited at high concentrations. The average inhibition ratios of ß-glucosidase, urease, and catalase in high Cd levels were 19.9, 38.9, and 51.9%, respectively. Ecological dose-response models indicate that catalase and urease were the most Cd-sensitive of the enzymes studied and were suitable indicators of soil quality in high geological background areas. Structural equation modeling (SEM) indicates that soil properties influenced sensitive enzymes through various pathways, indicating that soil properties were factors determining Cd inhibition of enzyme activities. This suggests that Cd concentrations and soil physicochemical properties under a range of environmental conditions should be considered in addressing soil Cd pollution.

Geotechnical characteristics and stability analysis of rock-soil aggregate slope at the Gushui Hydropower Station, southwest China.

Two important features of the high slopes at Gushui Hydropower Station are layered accumulations (rock-soil aggregate) and multilevel toppling failures of plate rock masses; the Gendakan slope is selected for case study in this paper. Geological processes of the layered accumulation of rock and soil particles are carried out by the movement of water flow; the main reasons for the toppling failure of plate rock masses are the increasing weight of the upper rock-soil aggregate and mountain erosion by river water. Indoor triaxial compression test results show that, the cohesion and friction angle of the rock-soil aggregate decreased with the increasing water content; the cohesion and the friction angle for natural rock-soil aggregate are 57.7 kPa and 31.3° and 26.1 kPa and 29.1° for saturated rock-soil aggregate, respectively. The deformation and failure mechanism of the rock-soil aggregate slope is a progressive process, and local landslides will occur step by step. Three-dimensional limit equilibrium analysis results show that the minimum safety factor of Gendakan slope is 0.953 when the rock-soil aggregate is saturated, and small scale of landslide will happen at the lower slope.

Experimental research on the dam-break mechanisms of the Jiadanwan landslide dam triggered by the Wenchuan earthquake in China.

Dam breaks of landslide dams are always accompanied by large numbers of casualties, a large loss of property, and negative influences on the downstream ecology and environment. This study uses the Jiadanwan landslide dam, created by the Wenchuan earthquake, as a case study example. Several laboratory experiments are carried out to analyse the dam-break mechanism of the landslide dam. The different factors that impact the dam-break process include upstream flow, the boulder effect, dam size, and channel discharge. The development of the discharge channel and the failure of the landslide dam are monitored by digital video and still cameras. Experimental results show that the upstream inflow and the dam size are the main factors that impact the dam-break process. An excavated discharge channel, especially a trapezoidal discharge channel, has a positive effect on reducing peak flow. The depth of the discharge channel also has a significant impact on the dam-break process. The experimental results are significant for landslide dam management and flood disaster prevention and mitigation.