Pulmonary delivery of icariin-phospholipid complex prolongs lung retention and improves therapeutic efficacy in mice with acute lung injury/ARDS.

Icariin has been shown the promising therapeutic potential to treat inflammatory airway diseases, yet its poor lung distribution and retention restrict the clinical applications. To this end, this work aimed to prepare an icariin-phospholipid complex (IPC) formulation for sustained nebulization delivery that enabled excellent inhalability, improved lung exposure and prolonged duration of action. Icariin was found to react with soybean phospholipid to form supramolecular IPC, which was able to self-assemble into nanoparticle suspension. The suspension was stable during steam sterilization and nebulization processes, and its aerosols generated by a commercial nebulizer exhibited excellent aerodynamic properties and delivery efficiency. In vitro studies showed that the formation of complex sustained drug release, enhanced lung affinity and slowed lung clearance. The drug distribution in lung epithelial lining fluid (ELF) also demonstrated in vivo sustained release after intratracheal administration to mice. In addition, compared to free icariin, IPC improved the drug exposure to lung tissues and immune cells in the ELF by 4.61-fold and 39.5-fold, respectively. This resulted in improved and prolonged local anti-inflammatory effects up to 24 h in mice with lipopolysaccharide (LPS)-induced acute lung injury. Moreover, IPC improved survival rate of mice with acute respiratory distress syndrome (ARDS). Overall, the present phospholipid complex represented a promising formulation of icariin for the treatment of acute lung injury/ARDS by nebulization delivery.

Fight or flee, a vital choice for Clostridioides difficile.

Clostridioides difficile is a leading cause of healthcare-associated infections, causing billions of economic losses every year. Its symptoms range from mild diarrhea to life-threatening damage to the colon. Transmission and recurrence of C. difficile infection (CDI) are mediated by the metabolically dormant spores, while the virulence of C. difficile is mainly due to the two large clostridial toxins, TcdA and TcdB. Producing toxins or forming spores are two different strategies for C. difficile to cope with harsh environmental conditions. It is of great significance to understand the molecular mechanisms for C. difficile to skew to either of the cellular processes. Here, we summarize the current understanding of the regulation and connections between toxin production and sporulation in C. difficile and further discuss the potential solutions for yet-to-be-answered questions.

Lipid-lowering Therapies and Long-term Stroke Prevention in East Asians: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Stroke prevention is a pressing global health priority, with reducing elevated lipids recognized as a key strategy. East Asians, constituting over 1.6 billion individuals and the largest racial group worldwide, are a key demographic in this effort. Yet, the effectiveness of lipid-lowering therapies for stroke prevention in this population remains uncertain. AIMS AND METHODS: We conducted a systematic review and meta-analysis of large-scale randomized controlled trials (RCTs) with at least 3 years of follow-up to evaluate the long-term impact of lipid-lowering therapies on stroke incidence in East Asians. We systematically searched four electronic databases up to January 11, 2024. The association was quantified using relative risk (RR) with a 95% confidence interval (CI), and between-study heterogeneity was evaluated using the I2 statistic. Additionally, we utilized the Cochrane Risk of Bias Tool to assess the risk of bias in each included RCT and applied the GRADE approach to evaluate the certainty of the evidence. RESULTS: This study incorporated data from 9 large-scale RCTs involving 54,354 participants. Our findings of overall analyses revealed that lipid-lowering therapies did not significantly affect the long-term incidence of all strokes (9 RCTs; 54,354 participants; RR, 0.98 [95% CI, 0.87-1.10]; P = 0.75), ischemic stroke (7 RCTs; 52,059 participants; RR, 0.91 [95% CI, 0.79-1.04]; P = 0.16), or hemorrhage stroke (7 RCTs; 52,059 participants; RR, 1.24 [95% CI, 0.97-1.59]; P = 0.09) in East Asians. Notably, there was no evidence of heterogeneity or publication bias, and the quality of evidence assessed using GRADE methodologies was rated as high. Sensitivity analyses confirmed the robustness of our results, with no single study significantly affecting the overall findings. Furthermore, subgroup analyses consistently supported the conclusions, further bolstering the reliability of our study. CONCLUSIONS: Lipid-lowering therapies did not demonstrate any beneficial effects on long-term stroke prevention among East Asians.

Assessment of the reversibility of resistance in the absence of antibiotics and its relationship with the resistance gene's fitness cost: a genetic study with mcr-1.

BACKGROUND: The intensive use of antibiotics has resulted in strong natural selection for the evolution of antimicrobial resistance (AMR), but whether, and under what circumstances, the removal of antibiotics would result in a rapid reduction in AMR has been insufficiently explored. We aimed to test the hypothesis that in the simple, yet common, case of AMR conferred by a single gene, removing antibiotics would quickly reduce the prevalence of resistance if the AMR gene imposes a high fitness cost and costless resistance is extremely rare among its proximal mutants. METHODS: In this genetic study, to test our hypothesis, we used the mcr-1 gene in Escherichia coli, which confers resistance to the last-resort antibiotic colistin, as a model. A high-throughput reverse genetics approach was used to evaluate mcr-1 variants for their fitness cost and resistance levels relative to a non-functional construct, by measuring relative growth rates in colistin-free media and at 2 µg/mL and 4 µg/mL colistin. We identified costless resistant mcr-1 mutants, and examined their properties within the context of the sequential organisation of mcr-1's functional domains as well as the evolutionary accessibility of these mutations. Finally, a simple population genetic model incorporating the measured fitness cost was constructed and tested against previously published real-world data of mcr-1 prevalence in colonised inpatients in China since the 2017 colistin ban in fodder additives. FINDINGS: We estimated the relative growth rates of 14 742 mcr-1 E coli variants (including the wild type), 3449 of which were single-nucleotide mutants. E coli showed 73·8% less growth per 24 h when carrying wild-type mcr-1 compared with the non-functional construct. 6252 (42·4%) of 14 741 mcr-1 mutants showed colistin resistance accompanied by significant fitness costs, when grown under 4 µg/mL colistin selection. 43 (0·3%) mcr-1 mutants exhibited costless resistance, most of which contained multiple mutations. Among the 3449 single mutants of mcr-1, 3433 (99·5%) had a fitness cost when grown in colistin-free media, with a mean relative growth of 0·305 (SD 0·193) compared with the non-functional variant. 3059 (88·7%) and 1833 (53·1%) of 3449 single mutants outgrew the non-functional mcr-1 in the presence of 2 µg/mL and 4 µg/mL colistin, respectively. Single mutations that gave rise to costless mutants were rare in all three domains of mcr-1 (transmembrane domain, flexible linker, and catalytic domain), but the linker domain was enriched with cost-reducing and resistance-enhancing mutations and depleted with cost-increasing mutations. The population genetics model based on the experimental data accurately predicts the rapid decline in mcr-1 prevalence in real-world data. INTERPRETATION: Many identified costless resistant variants that consist of multiple mutations are unlikely to evolve easily in nature. These findings for colistin and mcr-1 might be applicable to other cases in which AMR entails a substantial fitness cost that cannot be mitigated in proximal mutants. FUNDING: National Natural Science Foundation of China, and National Key Research and Development Program of China.

NLRC5 promotes endometrial carcinoma progression by regulating NF-κB pathway-mediated mismatch repair gene deficiency.

The innate immune molecule NLR family CARD domain-containing 5 (NLRC5) plays a significant role in endometrial carcinoma (EC) immunosurveillance. However, NLRC5 also plays a protumor role in EC cells. Mismatch repair gene deficiency (dMMR) can enable tumors to grow faster and also can exhibit high sensitivity to immune checkpoint inhibitors. In this study, we attempted to determine whether NLRC5-mediated protumor role in EC is via the regulation of dMMR. Our findings revealed that NLRC5 promoted the proliferation, migration, and invasion abilities of EC cells and induced the dMMR status of EC in vivo and in vitro. Furthermore, the mechanism underlying NLRC5 regulated dMMR was also verified. We first found NLRC5 could suppress nuclear factor-kappaB (NF-κB) pathway in EC cells. Then we validated that the positive effect of NLRC5 in dMMR was restricted when NF-κB was activated by lipopolysaccharides in NLRC5-overexpression EC cell lines. In conclusion, our present study confirmed the novel NLRC5/NF-κB/MMR regulatory mechanism of the protumor effect of NLRC5 on EC cells, thereby suggesting that the NLRC5-mediated protumor in EC was depend on the function of MMR.

Application and prospect of BSA method based on bibliometrics in crop breeding.

In order to understand the progress and frontier in the application of BSA(bulked segregant analysis) method in crop breeding and to reflect objectively the contribution of different countries, institutions and researchers in this field at home and abroad, this study analyzed 2111 items in the WOS (Web of Science) database from 2000 to 2023 and 446 items in the CNKI (China National through Knowledge Infrastructure) database from 2003 to 2023, regarding the researches of the application of BSA in crop breeding, basing on bibliometric analysis methods using CiteSpace software including keyword co-occurrence analysis, highlight word analysis, keyword clustering analysis, clustering timeline analysis and author co-citation. The results showed that there was an consistent increasing trend in the publication number of the application of BSA in crop breeding both in the domestic and foreign journals year by year. Ranking of the top countries according to the number of publications was China, the United States and India. The Huazhong Agricultural University displayed the highest number of publications in the CNKI database, while the Chinese Academy of Agricultural Sciences was found to have the highest number of publications in the WOS database. The published articles related to the application of BSA in crop breeding abroad mainly focused on the disciplines such as plant science, agronomy, horticulture and genetics, while those in China mainly concentrated on such disciplines as plant science, plant protection, horticulture and biology. The top three authors in terms of influence in the field of appling BSA in crop breeding were Michelmore RW, Kosambi DD and Li H, while Michelmore RW, Lander ES and Li H had closer cooperations with other authors. The top three crops relating to the studies of BSA were rice(Oryza sativa), soybean(Glycine max), corn(Zea mays L.) with the hot spot traits of disease resistance and plant height domestically. The top three crops involving the studies of BSA were rice, Arabidopsis thaliana and wheat(Triticum aestivum L.) with hot spot traits of disease resistance abroad. Up to now, BSA was mainly used to localize and functionally verify the candidate genes linking target traits and the mutated genes in crops in the domestical documents, while the foreign published studies based on BSA were mainly focused on the fine mapping and functional verification of target trait genes aiming at the revelation of genetic mechanisms in crops. Research frontier analysis indicated that rice, peanuts(Arachis hypogaea L.), upland cotton(Gossypium hirsutum L.) would be the main objects of studies concerning application of BSA in crop breeding with the hot topics of crop mutants and crop metabolites in the future.

High-throughput mutagenesis and screening approach for the identification of drug-resistant mutations in the rifampicin resistance-determining region of mycobacteria.

Rifampicin is the most powerful first-line antibiotic for tuberculosis, which is caused by Mycobacterium tuberculosis. Although accumulating evidence from sequencing data of clinical M. tuberculosis isolates suggested that mutations in the rifampicin-resistance-determining region (RRDR) are strongly associated with rifampicin resistance, the comprehensive characterisation of RRDR polymorphisms that confer this resistance remains challenging. By incorporating I-SceI sites for I-SceI-based integrant removal and utilizing an L5 swap strategy, we efficiently replaced the integrated plasmid with alternative alleles, making mass allelic exchange feasible in mycobacteria. Using this method to establish a fitness-related gain-of function screen, we generated a mutant library that included all single-amino-acid mutations in the RRDR, and identified the important positions corresponding to some well-known rifampicin-resistance mutations (Q513, D516, S522, H525, R529, S531). We also detected a novel two-point mutation located in the RRDR confers a fitness advantage to M. smegmatis in the presence or absence of rifampicin. Our method provides a comprehensive insight into the growth phenotypes of RRDR mutants and should facilitate the development of anti-tuberculosis drugs.

Long non-coding RNAFOXD1-AS1 modulated CTCs epithelial-mesenchymal transition and immune escape in hepatocellular carcinoma in vitro by sponging miR-615-3p.

BACKGROUND: Hepatocellular carcinoma (HCC) is widely recognized as a globally prevalent malignancy. Immunotherapy is a promising therapy for HCC patients. Increasing evidence suggests that lncRNAs are involved in HCC progression and immunotherapy. AIM: The study reveals the mechanistic role of long non-coding RNA (lncRNA) FOXD1-AS1 in regulating migration, invasion, circulating tumor cells (CTCs), epithelial-mesenchymal transition (EMT), and immune escape in HCC in vitro. METHODS: This study employed real-time PCR (RT-qPCR) to measure FOXD1-AS1, miR-615-3p, and programmed death-ligand 1 (PD-L1). The interactions of FOXD1-AS1, miR-615-3p, and PD-L1 were validated via dual-luciferase reporter gene and ribonucleoprotein immunoprecipitation (RIP) assay. In vivo experimentation involves BALB/c mice and BALB/c nude mice to investigate the impact of HCC metastasis. RESULTS: The upregulation of lncRNA FOXD1-AS1 in malignant tissues significantly correlates with poor prognosis. The investigation was implemented on the impact of lncRNA FOXD1-AS1 on the migratory, invasive, and EMT of HCC cells. It has been observed that the lncRNA FOXD1-AS1 significantly influences the generation and metastasis of MCTC in vivo analysis. In mechanistic analysis, lncRNA FOXD1-AS1 enhanced immune escape in HCC via upregulation of PD-L1, which acted as a ceRNA by sequestering miR-615-3p. Additionally, lncRNA FOXD1-AS1 was found to modulate the EMT of CTCs through the activation of the PI3K/AKT pathway. CONCLUSION: This study presents compelling evidence supporting the role of lncRNA FOXD1-AS1 as a miRNA sponge that sequesters miR-655-3p and protects PD-L1 from suppression.

Silica monolayer isolation of electrodeposited SERS substrate and online probing of molecule adsorption onto mineral microparticles in relation to flotation.

In the minerals processing industry, the surface chemistry of mineral particles and its real-time detection can significantly enhance process performance, and ultimately leading to automotive and intelligent control. The adsorption of collector molecule onto bulk mineral specimens could be investigated with the help of shell-isolated nanoparticle enhanced Raman spectroscopy (SHINERS). However, this method is unsuitable for the online detection of particles fluid consisted of micro-sized chalcocite that encountered in industrial production processes. In this work, a novel strategy of shell-isolated nanoparticles synthesis by electrodeposition of gold nanoparticles film and isolation of this film with crosslinked silica monolayer was proposed. The adsorption of 2-mercaptobenzothiazole (MBT), a typical flotation collector, onto a copper sulfide mineral, chalcocite was measured in-situ with the help of such a SERS substrate. Enhancement factors of 106-107 was calculated based on an idealized model. Furthermore, we discussed the stability of the silica isolation monolayer under high-power laser irradiation.

Arginine-Enhanced Antimicrobial Activity of Nanozymes against Gram-Negative Bacteria.

The continuous reduction of clinically available antibiotics has made it imperative to exploit more effective antimicrobial therapies, especially for difficult-to-treat Gram-negative pathogens. Herein, it is shown that the combination of an antimicrobial nanozyme with the clinically compatible basic amino acid L-arginine affords a potent treatment for infections with Gram-negative pathogens. In particular, the antimicrobial activity of the antimicrobial nanozyme is dramatically increased by ≈1000-fold after L-arginine stimulation. Specifically, the combination therapy enhances bacterial outer and inner membrane permeability and promotes intracellular reactive oxygen species (ROS) generation. Moreover, the metabolomic and transcriptomic results reveal that combination treatment leads to the increased ROS-mediated damage by inhibiting the tricarboxylic acid cycle and oxidative phosphorylation, thereby inducing an imbalance of the antioxidant and oxidant systems. Importantly, L-arginine dramatically significantly accelerates the healing of infected wounds in mouse models of multidrug-resistant peritonitis-sepsis and skin wound infection. Overall, this work demonstrates a novel synergistic antibacterial strategy by combining the antimicrobial nanozymes with L-arginine, which substantively facilitates the nanozyme-mediated killing of pathogens by promoting ROS production.

Electrochemically Promoted Three-Component Reaction to N-Sulfonyl Amidines.

In this study, a multicomponent reaction via the Mannich intermediate was developed using methanol, secondary amine, and sulfonamide as starting materials. This method uses methanol as a green C1 source. The substrate scope is wide, and the yield is good. The mechanistic study shows that methanol generates formaldehyde under electrochemical conditions, and sulfonyl amidine as a nucleophile reacts with Schiff base intermediates to form N-sulfonyl amidine in a single step.

A new variant of the colistin resistance gene MCR-1 with co-resistance to ß-lactam antibiotics reveals a potential novel antimicrobial peptide.

The emerging and global spread of a novel plasmid-mediated colistin resistance gene, mcr-1, threatens human health. Expression of the MCR-1 protein affects bacterial fitness and this cost correlates with lipid A perturbation. However, the exact molecular mechanism remains unclear. Here, we identified the MCR-1 M6 variant carrying two-point mutations that conferred co-resistance to ß-lactam antibiotics. Compared to wild-type (WT) MCR-1, this variant caused severe disturbance in lipid A, resulting in up-regulation of L, D-transpeptidases (LDTs) pathway, which explains co-resistance to ß-lactams. Moreover, we show that a lipid A loading pocket is localized at the linker domain of MCR-1 where these 2 mutations are located. This pocket governs colistin resistance and bacterial membrane permeability, and the mutated pocket in M6 enhances the binding affinity towards lipid A. Based on this new information, we also designed synthetic peptides derived from M6 that exhibit broad-spectrum antimicrobial activity, exposing a potential vulnerability that could be exploited for future antimicrobial drug design.

Caspase-9 inhibition triggers Hsp90-based chemotherapy-mediated tumor intrinsic innate sensing and enhances antitumor immunity.

BACKGROUND: Antineoplastic chemotherapies are dramatically efficient when they provoke immunogenic cell death (ICD), thus inducing an antitumor immune response and even tumor elimination. However, activated caspases, the hallmark of most cancer chemotherapeutic agents, render apoptosis immunologically silent. Whether they are dispensable for chemotherapy-induced cell death and the apoptotic clearance of cells in vivo is still elusive. METHODS: A rational cell-based anticancer drug library screening was performed to explore the immunogenic apoptosis pathway and therapeutic targets under apoptotic caspase inhibition. Based on this screening, the potential of caspase inhibition in enhancing chemotherapy-induced antitumor immunity and the mechanism of actions was investigated by various cells and mouse models. RESULTS: Heat shock protein 90 (Hsp90) inhibition activates caspases in tumor cells to produce abundant genomic and mitochondrial DNA fragments and results in cell apoptosis. Meanwhile, it hijacks Caspase-9 signaling to suppress intrinsic DNA sensing. Pharmacological blockade or genetic deletion of Caspase-9 causes tumor cells to secrete interferon (IFN)-ß via tumor intrinsic mitochondrial DNA/the second messenger cyclic GMP-AMP (cGAS) /stimulator of interferon genes (STING) pathway without impairing Hsp90 inhibition-induced cell death. Importantly, both Caspase-9 and Hsp90 inhibition triggers an ICD, leading to the release of numerous damage-associated molecular patterns such as high-mobility group box protein 1, ATP and type I IFNs in vitro and remarkable antitumor effects in vivo. Moreover, the combination treatment also induces adaptive resistance by upregulating programmed death-ligand 1 (PD-L1). Additional PD-L1 blockade can further overcome this acquired immune resistance and achieve complete tumor regression. CONCLUSIONS: Blockade of Caspase-9 signaling selectively provokes Hsp90-based chemotherapy-mediated tumor innate sensing, leading to CD8+ T cell-dependent tumor control. Our findings implicate that pharmacological modulation of caspase pathway increases the tumor-intrinsic innate sensing and immunogenicity of chemotherapy-induced apoptosis, and synergizes with immunotherapy to overcome adaptive resistance.

[Environmental pollutants and Alzheimer's disease].

Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive cognitive impairment. The main hypotheses about the pathogenesis of AD include the hypothesis of ß-amyloid protein, the hypothesis of abnormal phosphorylation of Tau protein, and the hypothesis of neuroinflammation. In recent years, environmental pollutants have been considered as an important factor in causing neurological dysfunction. Common environmental pollutants include heavy metals, pesticides, polychlorinated biphenyls, microplastics, and air pollutants, all of which have been proven to have neurotoxicity. In this review, we not only discussed epidemiological and animal experimental studies that link environmental pollution with AD, but also summarized the mechanisms of action of relevant toxins, providing insights for studying the interrelationships between environmental pollutants and AD.

Parallel evolution, atavism, and extensive introgression explain the radiation of Epimedium sect. Diphyllon (Berberidaceae) in southern East Asia.

East Asia is the richest region of plant biodiversity in the northern temperate zone, and its radiation provides key insights for understanding rapid speciation, including evolutionary patterns and processes. However, it is challenging to investigate the recent evolutionary radiation among plants because of the lack of genetic divergence, phenotypic convergence, and interspecific gene flow. Epimedium sect. Diphyllon is a rarely studied plant lineage endemic to East Asia, especially highly diversified in its southern part. In this study, we report a robust phylogenomic analysis based on genotyping-by-sequencing data of this lineage. The results revealed a clear biogeographic pattern for Epimedium sect. Diphyllon with recognition into two major clades corresponding to the Sino-Himalayan and Sino-Japanese subkingdoms of East Asian Flora and rapid diversification of the extant species dated to the Pleistocene. Evolutionary radiation of Epimedium sect. Diphyllon is characterized by recent and predominant parallel evolution and atavism between the two subkingdom regions, with extensive reticulating hybridization within each region during the course of diversification in southern East Asia. A parallel-atavism-introgression hypothesis is referred to in explaining the radiation of plant diversity in southern East Asia, which represents a potential model for the rapid diversification of plants under global climate cooling in the late Tertiary. Our study advances our understanding of the evolutionary processes of plant radiation in East Asia as well as in other biodiversity hotspot regions.

Seasonal variation characteristics and influencing factors of dissolved organic carbon of soil water in permafrost peatlands of the Great Hing'an Mountains in summer and autumn.

Dissolved organic carbon (DOC) plays a crucial role in the assessment of greenhouse gas emission and carbon balance in peatlands. However, limited research has been conducted on the seasonal variations and properties of soil water DOC content at different depths in the permafrost peatlands of the Great Hing'an Mountains. In this study, we analyzed the seasonal patterns of soil water DOC contents (surface, 10 cm, 20 cm, 30 cm, 40 cm, and permafrost layer) the permafrost peatlands of the Great Hing'an Mountains (Tuqiang Forestry Bureau), and investigated the influencing factors, such as electrical conductivity, dissolved oxygen, HCO3- concentration, pH value, oxidation-reduction potential, and CO2 content. The stability of DOC was assessed by using UV-Vis spectrum. There were significant seasonal dynamics of DOC content in soil water, with higher contents in autumn and lower content in summer, ranging from 55.7 to 188.1 mg·L-1. There were significant differences in DOC content among different soil depths, with the highest levels detected in the permafrost layer. The DOC content showed a significantly positive correlation with pH value and electrical conductivity, while showed a significantly negative correlation with redox potential, HCO3- concentration, and dissolved oxygen content. Additionally, there was a significantly positive correlation between DOC and CO2 contents. The dissolved CO2 content in soil water increased with soil depth, with the highest content observed in the permafrost layer. Results of spectral analysis showed higher aromaticity in autumn compared to summer, indicating greater stability of DOC during the autumn season. Our results clarified the seasonal variations of soil water DOC in permafrost peatlands of the Great Hing'an Mountains and could provide important data to understand the carbon cycling in the region.

[Recent research on inhaled nitric oxide in preterm infants with a gestational age of <34 weeks]. / 胎龄<34å‘¨æ—©äº§å„¿ä¸€æ°§åŒ–æ°®å¸å ¥çš„ç ”ç©¶è¿›å±•.

Nitric oxide is a messenger molecule for vasodilation of vascular smooth muscle cells, and inhaled nitric oxide (iNO) can dilate pulmonary blood vessels and reduce pulmonary vascular resistance, thereby reducing pulmonary artery pressure, but with no influence on systemic circulation pressure. Guidelines in China and overseas recommend the use of iNO in full-term infants and late preterm infants, and it has been proved that it has a marked effect on persistent pulmonary hypertension and hypoxic respiratory failure in such infants. However, recent studies have shown that there is an increase in the off-label use of iNO in preterm infants with a gestational age of <34 weeks. This article reviews the research progress on the efficacy, safety, timing, dose, and withdrawal mode of iNO and its combination with vasoactive drugs in the treatment of preterm infants with a gestational age of <34 weeks in China and overseas, so as to provide a reference for clinical application.

Antibacterial oxygenated ergostane-type steroids produced by the marine sponge-derived fungus Aspergillus sp.

Two oxygenated ergostane-type steroids including one new compound, 3ß-hydroxy-5α,6ß-methoxyergosta-7,22-dien-15-one (1) along with a known analogue ergosta-6,22-dien-3ß,5α,8α-triol (2) were isolated from the crude extracts of the marine sponge-derived fungus Aspergillus sp. Their structures were elucidated on the basis of combined NMR and MS spectroscopic methods. Compound 1 was a marine ergostane-type steroid with two methoxy groups at C-5 and C-6, respectively. These oxygenated ergostane-type steroids were evaluated for their antibacterial activities against human or aquatic pathogens. Among them, compound 1 exhibited antibacterial activity against Staphylococcus aureus.

[Analysis of the causes of soft tissue complications after volar locking plate for the treatment of dorsal displaced distal radius fractures].

OBJECTIVE: To investigate the causes of soft tissue complications in patients with dorsal displacement distal radius fractures (DRF) after volar locking plate surgery. METHODS: From July 2016 to May 2021, 112 patients with dorsal displacement DRF were treated with volar locking plate surgery, including 45 males and 67 females. The average age was (46.24±10.08) years old, ranging from 18 to 85 years old. According to whether there were soft tissue complications after operation, they were divided into complication group (40 cases) and non complication group (72 cases). Compared with preoperation, the radial metacarpal inclination and ulnar deflection angle, wrist flexion activity and dorsal extension activity, and grip strength of patients after operation were significantly improved (P<0.05). Compared with the non complication group, the proportion of patients in the complication group whose age was>60 years, body mass index (BMI) more than 30 kg·m-2, smoking, diabetes, fracture type C, open fracture and operation time more than 90 min was higher (P<0.05). The age, BMI, smoking, diabetes, fracture AO classification, fracture type and operation time were analyzed by multifactor Logistic regression to determine the independent risk factors affecting the occurrence of postoperative soft tissue complications of patients, establish a nomogram prediction model, and evaluate the model. RESULTS: At the latest follow-up, the excellent and good rate of wrist joint function recovery was 83.93% (94/112), and the excellent and good rate of fracture reduction was 84.82% (95/112). Multivariate Logistic regression analysis showed that age more than 60 years old, diabetes, fracture type C, open fracture and operation time more than 90 min were independent risk factors for postoperative soft tissue complications (P<0.05). The receiver operating characteristic (ROC), calibration curve and clinical decision curve of the nomogram prediction model showed discrimination, accuracy and validity were good. CONCLUSION: Age more than 60 years, diabetes mellitus, fracture type C, open fracture, and operation time more than 90 min are all independent risk factors for soft tissue complications after DRF volar plate fixation. In clinical treatment, perioperative soft tissue management should be done in such patients to prevent complications.