Rainfall and nitrogen addition have no synergistic effects on steppe composition and production in postgrazing succession

Most steppes are experiencing postgrazing succession, coupled with rainfall change and nitrogen (N) deposition. Despite the importance of soil resources in shaping community multifunctionality, little is known about how rainfall increase and N deposition influence steppe composition and production during postgrazing succession. We performed a field factorial experiment, subject to rainfall and N, each with three levels, to understand how simulated rainfall increase and N deposition affect the composition and production of a Leymus chinensis steppe. At the low rainfall increase, the dominance of L. chinensis increased with increasing N, while aboveground community production remained unchanged along the N gradient. At the high rainfall increase, aboveground community production was enhanced due to low N addition, but this facilitation disappeared in the presence of high N addition, and L. chinensis dominance was no longer affected by N. N-induced soil eutrophication but not soil acidification and soil microbes strongly affected steppe composition and production. Our findings suggest that high rainfall increase might weaken the potential of N addition to contribute to steppe composition and production, and also highlight the necessity of investigating interactions among multiple global change drivers

Lipid engineering combined with systematic metabolic engineering of <i>Saccharomyces cerevisiae</i> for high-yield production of lycopene

Saccharomyces cerevisiae is an efficient host for natural-compound production and preferentially employed in academic studies and bioindustries. However, S. cerevisiae exhibits limited production capacity for lipophilic natural products, especially compounds that accumulate intracellularly, such as polyketides and carotenoids, with some engineered compounds displaying cytotoxicity. In this study, we used a nature-inspired strategy to establish an effective platform to improve lipid oil–triacylglycerol (TAG) metabolism and enable increased lycopene accumulation. Through systematic traditional engineering methods, we achieved relatively high-level production at 56.2 mg lycopene/g cell dry weight (cdw). To focus on TAG metabolism in order to increase lycopene accumulation, we overexpressed key genes associated with fatty acid synthesis and TAG production, followed by modulation of TAG fatty acyl composition by overexpressing a fatty acid desaturase (OLE1) and deletion of Seipin (FLD1), which regulates lipid-droplet size. Results showed that the engineered strain produced 70.5 mg lycopene/g cdw, a 25% increase relative to the original high-yield strain, with lycopene production reaching 2.37 g/L and 73.3 mg/g cdw in fed-batch fermentation and representing the highest lycopene yield in S. cerevisiae reported to date. These findings offer an effective strategy for extended systematic metabolic engineering through lipid engineering

Bilateral distal transradial access for subclavian artery stenosis intervention

BackgroundConventionally, subclavian stenting has been performed via the femoral artery, but this approach is associated with complications such as bleeding, patient discomfort, and prolonged recovery. The transradial artery access (TRA) has gained popularity due to its lower vascular complication rates, though it carries a risk of radial artery occlusion (RAO). The distal transradial access (dTRA) has emerged as an alternative with lower occlusion rates.ObjectiveThis study aimed to assess the safety and technical feasibility of bilateral distal transradial access for percutaneous interventions in subclavian artery stenosis.MethodsWe present 10 cases of subclavian artery stenosis, in whom diagnostic angiography was performed by SIM2 catheter via the contralateral side access. Ipsilateral side distal radial artery was subsequently accessed for balloon-expandable stents delivery.ResultsAmong the 10 patients, 9 were male and 1 was female, with a mean age of 65.8 years. The systolic pressure difference between the left and right arms was 21.00 mmHg. Among them, 2 cases had 80% stenosis, 2 cases had total occlusive lesions, and 6 cases had 90% stenosis. 1 case had right subclavian artery stenosis, while 9 cases had left subclavian artery stenosis. The results showed a 100% success rate for bilateral distal radial artery puncture and a 100% completion rate for subclavian stenosis intervention procedures. No RAO or subclavian artery restenosis was observed during the 1-month follow-up.ConclusionIn patients with subclavian stenosis bilateral dTRA is a safe and minimally invasive method for patients and ergonomically comfortable for operators

Engineered Streptomyces lividans Strains for Optimal Identification and Expression of Cryptic Biosynthetic Gene Clusters

Streptomyces lividans is a suitable host for the heterologous expression of biosynthetic gene clusters (BGCs) from actinomycetes to discover “cryptic” secondary metabolites. To improve the heterologous expression of BGCs, herein we optimized S. lividans strain SBT5 via the stepwise integration of three global regulatory genes and two codon-optimized multi-drug efflux pump genes and deletion of a negative regulatory gene, yielding four engineered strains. All optimization steps were observed to promote the heterologous production of polyketides, non-ribosomal peptides, and hybrid antibiotics. The production increments of these optimization steps were additional, so that the antibiotic yields were several times or even dozens of times higher than the parent strain SBT5 when the final optimized strain, S. lividans LJ1018, was used as the heterologous expression host. The heterologous production of these antibiotics in S. lividans LJ1018 and GX28 was also much higher than in the strains from which the BGCs were isolated. S. lividans LJ1018 and GX28 markedly promoted the heterologous production of secondary metabolites, without requiring manipulation of gene expression components such as promoters on individual gene clusters. Therefore, these strains are well-suited as heterologous expression hosts for secondary metabolic BGCs. In addition, we successfully conducted high-throughput library expression and functional screening (LEXAS) of one bacterial artificial chromosome library and two cosmid libraries of three Streptomyces genomes using S. lividans GX28 as the library-expression host. The LEXAS experiments identified clones carrying intact BGCs sufficient for the heterologous production of piericidin A1, murayaquinone, actinomycin D, and dehydrorabelomycin. Notably, due to lower antibiotic production, the piericidin A1 BGC had been overlooked in a previous LEXAS screening using S. lividans SBT5 as the expression host. These results demonstrate the feasibility and superiority of S. lividans GX28 as a host for high-throughput screening of genomic libraries to mine cryptic BGCs and bioactive compounds

Cholestane-3β,5α,6β-triol induces cancer cell death by activating GSDME-mediated pyroptosis

BackgroundTrihydroxysterols and their analogues accumulate in several pathologies, including neurodegenerative diseases, cancers, and atherosclerosis. Cholestane-3β,5α,6β-triol (CT), recognized as an apoptosis-inducing agent, also exhibits pro-inflammatory effects. Nevertheless, the mechanisms underlying CT-induced cytotoxicity and inflammation remain incompletely characterized.MethodsRNA-sequencing (RNA-seq) analysis indicated CT can stimulate pro-inflammatory cytokine expression. We then employed multiple cell death inhibitors to confirm the predominant form of CT-induced cell death. Using combined chemical inhibition and genetic editing approaches, we established the relationship between caspase 3 activation, CT-mediated gasdermin E (GSDME) cleavage, and subsequent cell death.ResultsCT promotes the expression of multiple pro-inflammatory cytokines. Among inflammatory cell death effector proteins, GSDME was exclusively highly expressed in our cell model. Notably, CT-induced cytotoxicity was abolished by either pharmacological GSDME inhibition or genetic knockdown of GSDME expression. This GSDME-dependent cell death pathway was consistently observed across multiple cell lines. Furthermore, caspase 3 silencing mitigated CT-induced GSDME cleavage, thereby enhancing cell viability.ConclusionCT specifically triggered caspase 3-dependent GSDME cleavage, resulting in pyroptosis as the predominant form of CT-induced cell death. This study establishes a direct mechanistic link between CT and inflammatory cell death execution and provides insight into the contribution of trihydroxysterols to inflammatory pathogenesis

ISPO: An Integrated Ontology of Symptom Phenotypes for Semantic Integration of Traditional Chinese Medical Data

Symptom phenotypes are one of the key types of manifestations for diagnosis and treatment of various disease conditions. However, the diversity of symptom terminologies is one of the major obstacles hindering the analysis and knowledge sharing of various types of symptom-related medical data particularly in the fields of Traditional Chinese Medicine (TCM). Objective: This study aimed to construct an Integrated Ontology of symptom phenotypes (ISPO) to support the data mining of Chinese EMRs and real-world study in TCM field. Methods: To construct an integrated ontology of symptom phenotypes (ISPO), we manually annotated classical TCM textbooks and large-scale Chinese electronic medical records (EMRs) to collect symptom terms with support from a medical text annotation system. Furthermore, to facilitate the semantic interoperability between different terminologies, we incorporated public available biomedical vocabularies by manual mapping between Chinese terms and English terms with cross-references to source vocabularies. In addition, we evaluated the ISPO using independent clinical EMRs to provide a high-usable medical ontology for clinical data analysis. Results: By integrating 78,696 inpatient cases of EMRs, 5 biomedical vocabularies, 21 TCM books and dictionaries, ISPO provides 3,147 concepts, 23,475 terms, and 55,552 definition or contextual texts. Adhering to the taxonomical structure of the related anatomical systems of symptom phenotypes, ISPO provides 12 top-level categories and 79 middle-level sub-categories. The validation of data analysis showed the ISPO has a coverage rate of 95.35%, 98.53% and 92.66% for symptom terms with occurrence rates of 0.5% in additional three independent curated clinical datasets, which can demonstrate the significant value of ISPO in mapping clinical terms to ontologies.39 pages, 6 figures, 6 table

Genetic Evidence for the Association between the Early Growth Response 3 (EGR3) Gene and Schizophrenia

Recently, two genome scan meta-analysis studies have found strong evidence for the association of loci on chromosome 8p with schizophrenia. The early growth response 3 (EGR3) gene located in chromosome 8p21.3 was also found to be involved in the etiology of schizophrenia. However, subsequent studies failed to replicate this finding. To investigate the genetic role of EGR3 in Chinese patients, we genotyped four SNPs (average interval ∼2.3 kb) in the chromosome region of EGR3 in 470 Chinese schizophrenia patients and 480 healthy control subjects. The SNP rs35201266 (located in intron 1 of EGR3) showed significant differences between cases and controls in both genotype frequency distribution (P = 0.016) and allele frequency distribution (P = 0.009). Analysis of the haplotype rs35201266-rs3750192 provided significant evidence for association with schizophrenia (P = 0.0012); a significant difference was found for the common haplotype AG (P = 0.0005). Furthermore, significant associations were also found in several other two-, and three-SNP tests of haplotype analyses. The meta-analysis revealed a statistically significant association between rs35201266 and schizophrenia (P = 0.0001). In summary, our study supports the association of EGR3 with schizophrenia in our Han Chinese sample, and further functional exploration of the EGR3 gene will contribute to the molecular basis for the complex network underlying schizophrenia pathogenesis

Simulation of Steam-flooding Thermal Heavy Oil Recovery Process with Sequential Implicit Method

Abstract Numerical simulation of steam-flooding thermal heavy oil recovery is studied in this paper. Although the traditional full implicit scheme has high stability, it needs to calculate the huge sparse matrix and the computation cost is super expensive; so it cannot meet the needs of practical oil industry production. In this paper, sequential implicit scheme is applied to numerical computation of steam-flooding thermal heavy oil recovery. A quasi-one-dimension numerical example is tested to verify the validity and high efficiency of the proposed method against using traditional fully implicit scheme.</jats:p