12-Plex Isobaric Multiplex Labeling Reagents for Carbonyl-Containing Compound (SUGAR) Tag-Enabled High-Throughput Quantitative Glycomics.

Glycans, which are ubiquitously distributed on most proteins and cell surfaces, are a class of important biomolecules playing crucial roles in various biological processes such as molecular recognition and cellular communication. Modern mass spectrometry (MS) coupled with novel chemical probe labeling strategies has greatly advanced analysis of glycans. However, the requirement of high-throughput and robust quantitative analysis still calls for the development of more advanced tools. Recently, we devised isobaric multiplex reagents for carbonyl-containing compound (SUGAR) tags for 4-plex N-glycan analysis. To further improve the throughput, we utilized the mass-defect strategy and expanded the multiplexing capacity to 12 channels without changing the chemical structure of the SUGAR tag, achieving a threefold enhancement in throughput compared with the original design and managing to perform high-throughput N-glycan analysis in a single LC - MS/MS injection. Herein, we present detailed methods for the synthesis of 12-plex SUGAR isobaric tags, the procedure to release and label the N-glycans from proteins, and the analysis by high-resolution LC-MS/MS, as well as data processing to achieve multiplexed quantitative glycomics.

Ultra-sensitive detection of SARS-CoV-2 S1 protein by coupling rolling circle amplification with poly(N-isopropylacrylamide)-based sandwich-type assay.

In the past few years, the COVID-19 pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) seriously threatens global public health security due to its high contagiousness. It remains of vital importance to develop a rapid and sensitive assay for SARS-CoV-2. In this work, we proposed a sandwich-type assay based on poly(N-isopropylacrylamide) (PNIPAM), allowing efficient detection of the SARS-CoV-2 S1 protein in the homogeneous solution. Firstly, a direct sandwich-type assay was established with a linear range of 0.2-2 µg/mL and a limit of detection (LOD) of 0.11 µg/mL, which could realize rapid detection in about 1 h. Furthermore, the sandwich-type assay coupled with rolling circle amplification (RCA) obtained an increase in sensitivity of 5.9 × 104 folds with a wide linear range of 0.01 - 100 ng/mL and a LOD of 1.88 pg/mL. The average recoveries in unpretreated saliva were 90 %-113.0 %, indicating the potential of the developed method for application in practical samples. Given the high selectivity and sensitivity of the developed method, it has a significant potential for rapid and early detection of SARS-CoV-2.

Expanding the Structural Diversity of Tubulin-Targeting Agents: Development of Highly Potent Benzimidazoles for Treating Fungal Diseases.

Benzimidazoles, the representative pharmacophore of fungicides, have excellent antifungal potency, but their simple structure and single site of action have hindered their wider application in agriculture. In order to extend the structural diversity of tubulin-targeted benzimidazoles, novel benzimidazole derivatives were prepared by introducing the attractive pyrimidine pharmacophore. 2-((6-(4-(trifluoromethyl)phenoxy)pyrimidin-4-yl)thio)-1H-benzo[d]imidazole (A25) exhibited optimal antifungal activity against Sclerotinia sclerotiorum (S. s.), affording an excellent half-maximal effective concentration (EC50) of 0.158 µg/mL, which was higher than that of the reference agent carbendazim (EC50 = 0.594 µg/mL). Pot experiments revealed that compound A25 (200 µg/mL) had acceptable protective activity (84.7%) and curative activity (78.1%), which were comparable with that of carbendazim (protective activity: 90.8%; curative activity: 69.9%). Molecular docking displayed that multiple hydrogen bonds and π-π interactions could be formed between A25 and ß-tubulin, resulting in a stronger bonding effect than carbendazim. Fluorescence imaging revealed that the structure of intracellular microtubules can be changed significantly after A25 treatment. Overall, these remarkable antifungal profiles of constructed novel benzimidazole derivatives could facilitate the application of novel microtubule-targeting agents.

Separation and purification of benzylester glucosides and derivatives from tubers of Gymnadenia conopsea (L.) R. Br. by linear gradient counter-current chromatography combined with elution-extrusion mode.

Tubers of Gymnadenia conopsea (L.) R. Br. (Orchidaceae), a traditional medicine and food homologous plant, has a broad application and development prospect in the food and drug industries. Benzylester glucosides, the main effective active components in this plant, are difficult to separate due to their similar structures and high polarity. In this study, linear gradient counter-current chromatography was used to separate benzylester glucosides and derivatives, combined with elution-extrusion mode. The main separation parameters were optimized, including the ratio of mobile phase and sample loading. Finally, seven compounds were successfully separated, including 4-hydroxybenzyl alcohol (1), 4-hydroxybenzaldehyde (2), dactylorhin B (3), loroglossin (4), dactylorhin A (5), 4-(ethoxymethyl) phenol (6), and militarine (7). The structures were analyzed by mass spectrometry and nuclear magnetic resonance spectrometry. According to our findings, the established method was an efficient approach to separate benzylester glucosides and derivatives from tubers of G. conopsea. The established strategy could be applied to purify other similar high-polarity compounds from complex natural products.

Entecavir vs. tenofovir disoproxil fumarate in the treatment of chronic hepatitis B patients with severe acute exacerbation.

BACKGROUND: The efficacy of different nucleos(t)ide analogs in the treatment of chronic hepatitis B virus (CHB) with severe acute exacerbation (SAE) remained unclear. Thus, this study aimed to compare the short-term efficacy of tenofovir disoproxil fumarate (TDF) and entecavir (ETV) in patients having CHB with SAE. METHODS: We analyzed consecutive patients with treatment-naive CHB receiving TDF (n = 36) or ETV (n = 65) for SAE. The primary endpoint was overall mortality or receipt of liver transplantation (LT) by 24 weeks. The secondary endpoints are the comparison of ETV vs. TDF influences on renal function and virological and biochemical responses at 4, 12, 24, and 48 weeks. RESULTS: The baseline characteristics were comparable between the two groups. By 24 weeks, 8 (22%) patients in the TDF group and 10 (15%) patients in the ETV group had either died (n = 15) or received LT (n = 3) (P = 0.367). Cox-regression multivariate analysis revealed age (P = 0.003), baseline international normalized ratio of prothrombin time (P = 0.024), and early presence of hepatic encephalopathy (P = 0.003) as independent factors associated with mortality or LT. The two groups of patients achieved comparable biochemical and virological responses at 48 weeks. No significant difference was found in the estimated glomerular filtration rate (eGFR) between the TDF and the ETV groups. However, a significant reduction in the eGFR at 48 weeks, as compared with the baseline, was found in each group. CONCLUSION: TDF and ETV achieved similar short-term clinical outcomes and treatment responses in CHB patients with SAE.

Alternate levels versus all levels mini-plate fixation in C3-6 cervical laminoplasty: a retrospective comparative study.

OBJECTIVE: The purpose of this study is to compare radiological and clinical outcomes between alternate levels (C4 and C6) and all levels mini-plate fixation in C3-6 unilateral open-door laminoplasty. METHODS: Ninety-six patients who underwent C3-6 unilateral open-door laminoplasty with alternate levels mini-plate fixation (54 patients in group A) or all levels mini-plate fixation (42 patients in group B) between September 2014 and September 2019 were reviewed in this study. Radiologic and clinical outcomes were assessed. Clinical results included Visual Analogue Scale (VAS) of axial neck pain and Japanese Orthopedic Association (JOA) score. Radiographic results included cervical range of motion (ROM), cervical curvature index (CCI), and the spinal canal expansive parameters including open angle, anteroposterior diameter (APD), and Pavlov`s ratio. RESULTS: There was no significant difference in VAS, JOA score, ROM, and CCI between two groups. There was no significant difference in canal expansion postoperatively between two groups. However, open angle, APD, and Pavlov`s ratio in group A decreased significantly during the follow-up. In group B, APD, Pavlov`s ratio, and open angle were maintained until the final follow-up. There was no hardware failure or lamina reclosure occurred in both groups during the follow-up. The mean cost of group B was higher than that of group A. CONCLUSIONS: Despite the differences in the maintenance of canal expansion, alternate levels mini-plate fixation can achieve similar clinical outcomes as all levels mini-plate fixation in C3-6 unilateral open-door laminoplasty. As evidenced in this study, we believe C3-6 laminoplasty with alternate levels (C4 and C6) mini-plate fixation is an economical, effective, and safe treatment method.

Simultaneous detection of 5-methylcytosine and 5-hydroxymethylcytosine at specific genomic loci by engineered deaminase-assisted sequencing.

Cytosine modifications, particularly 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC), play crucial roles in numerous biological processes. Current analytical methods are often constrained to the separate detection of either 5mC or 5hmC, or the combination of both modifications. The ability to simultaneously detect C, 5mC, and 5hmC at the same genomic locations with precise stoichiometry is highly desirable. Herein, we introduce a method termed engineered deaminase-assisted sequencing (EDA-seq) for the simultaneous quantification of C, 5mC, and 5hmC at the same genomic sites. EDA-seq utilizes a specially engineered protein, derived from human APOBEC3A (A3A), known as eA3A-M5. eA3A-M5 exhibits distinct deamination capabilities for C, 5mC, and 5hmC. In EDA-seq, C undergoes complete deamination and is sequenced as T. 5mC is partially deaminated resulting in a mixed readout of T and C, and 5hmC remains undeaminated and is read as C. Consequently, the proportion of T readouts (P T) reflects the collective occurrences of C and 5mC, regulated by the deamination rate of 5mC (R 5mC). By determining R 5mC and P T values, we can deduce the precise levels of C, 5mC, and 5hmC at particular genomic locations. We successfully used EDA-seq to simultaneously measure C, 5mC, and 5hmC at specific loci within human lung cancer tissue and their normal counterpart. The results from EDA-seq demonstrated a strong concordance with those obtained from the combined application of BS-seq and ACE-seq methods. EDA-seq eliminates the need for bisulfite treatment, DNA oxidation or glycosylation and uniquely enables simultaneous quantification of C, 5mC and 5hmC at the same genomic locations.

Effect of ZIC2 on immune infiltration and ceRNA axis regulation in lung adenocarcinoma via bioinformatics and experimental studies.

OBJECTIVE: This study aimed to conclude the effect and mechanism of ZIC2 on immune infiltration in lung adenocarcinoma (LUAD). METHODS: Expression of ZIC2 in several kinds of normal tissues of TCGA data was analyzed and its correlation with the baseline characteristic of LUAD patients were analyzed. The immune infiltration analysis of LUAD patients was performed by CIBERSORT algorithm. The correlation analysis between ZIC2 and immune cell composition was performed. Additionally, the potential upstream regulatory mechanisms of ZIC2 were predicted to identify the possible miRNAs and lncRNAs that regulated ZIC2 in LUAD. In vitro and in vivo experiments were also conducted to confirm the potential effect of ZIC2 on cell proliferation and invasion ability of LUAD cells. RESULTS: ZIC2 expression was decreased in various normal tissues, but increased in multiple tumors, including LUAD, and correlated with the prognosis of LUAD patients. Enrichment by GO and KEGG suggested the possible association of ZIC2 with cell cycle and p53 signal pathway. ZIC2 expression was significantly correlated with T cells CD4 memory resting, Macrophages M1, and plasma cells, indicating that dysregulated ZIC2 expression in LUAD may directly influence immune infiltration. ZIC2 might be regulated by several different lncRNA-mediated ceRNA mechanisms. In vitro experiments validated the promotive effect of ZIC2 on cell viability and invasion ability of LUAD cells. In vivo experiments validated ZIC2 can accelerate tumor growth in nude mouse. CONCLUSION: ZIC2 regulated by different lncRNA-mediated ceRNA mechanisms may play a critical regulatory role in LUAD through mediating the composition of immune cells in tumor microenvironment.

[Past and present of endoscopic surgery and robotic surgery in treatment of breast diseases].

Objective: To review the research progress related to endoscopic surgery and robotic surgery for breast diseases, aiming to provide references for clinical practice. Methods: The recent domestic and international literature on endoscopic surgery and robotic surgery for breast diseases was reviewed, then the challenges in their development, the innovative evolution of endoscopic surgery combined with clinical practice by our team, and its clinical applications were summarized. Results: Traditional endoscopic surgery, despite its advantages such as minimal invasiveness, good cosmetic outcomes, and high patient's satisfaction, has been limited in its development due to specific difficulties in establishing the operative field. Our team innovatively proposed the "reverse sequence method" and the Huaxi Hole 1 theory and methods, cleverly altering the surgical procedure sequence, adding small operative orifices to transform single-port operations into multi-port ones, effectively overcoming the challenges restricting the advancement of endoscopic surgery in the field of breast diseases, thereby enabling further proliferation of endoscopic procedures. In terms of breast endoscopic reconstruction surgery, the parachute patch technique has broadened the indications for reconstruction surgery, benefiting patients with a certain degree of breast ptosis; and the postoperative adjustment concept, through early intervention in the post-reconstruction breast shape, has further refined the reconstruction procedure. Robot-assisted surgery derived from endoscopic surgery theory has further enhanced the precision and stability of surgeries, reducing surgical risks; however, excessive time and economic costs are urgent issues that must be addressed. Conclusion: Through theoretical innovations, endoscopic surgery has been applied in the excision and reconstruction of breast lesions, while robotic surgery shows promising applications in autologous breast reconstruction, especially in the latissimus dorsi reconstruction field. Nevertheless, the lack of high-level large-sample, multi-center randomized controlled clinical trials to confirm its surgical safety, oncological safety, and postoperative cosmetic outcomes is an important direction for future research.

[Effectiveness comparison of endoscopic removal of injectable Amazingel with/without immediate prepectoral implant-based breast augmentation].

Objective: To explore the surgical technique and preliminary safety and aesthetic results of endoscopic removal of injectable Amazingel with/without immediate prepectoral implant-based breast augmentation for patients. Methods: The clinical data of 25 patients who underwent endoscopic removal of injectable Amazingel with/without immediate prepectoral implant-based breast augmentation between April 2020 and January 2024 and met the selection criteria was retrospective analysed. The patients' age ranged from 33 to 73 years, with a mean of 50.4 years, and the body mass index ranged from 16.8 to 26.6 kg/m 2, with a mean of 21.5 kg/m 2. They were all bilaterally injected with Amazingel, and the time between initial injections and surgery ranged from 17 to 26 years, with a mean of 21.4 years. Early safety was evaluated by the incidence of early postoperative complications, and early aesthetic results were evaluated using Harris scores (including breast shape satisfaction, sensation satisfaction, and elasticity satisfaction) at 3 months after operation. Results: There were 9 cases underwent Amazingel removal (group A) and 16 cases underwent Amazingel removal with immediate prepectoral implant-based breast augmentation (group B). Intraoperative removal of Amazingel ranged from 808 to 1 285 mL, with a mean of 1 050.7 mL; the mass of the capsule removed ranged from 36 to 169 g, with a mean of 103.6 g; and a gross anatomical prosthesis was used with a median size of 345 mL (range, 315-355 mL). The operation time ranged from 95 to 395 minutes, with a mean of 194.2 minutes; and the cost of the procedure ranged from 8000to 91 000 yuan, with a mean of 33 000 yuan. Patients had a median follow-up time of 22.7 months (range, 3.0-48.1 months). There was 1 case of intraoperative skin burn due to the operation of the electric scalpel, which healed naturally after operation without flap necrosis. There was no adverse conditions such as prosthesis outline showing, ripple sign, and capsular contracture during follow-up; a small amount of Amazingel residue was found in 2 patients at 1 year after operation. The Harris score at 3 months after operation was used to evaluate the early aesthetic results, and the breast shape, elasticity, and sensation satisfaction of group A were lower than group B, but the differences between the two groups were not significant ( P>0.05). Conclusion: Endoscopic removal of injectable Amazingel with/without immediate prepectoral implant-based breast augmentation is safe in the early stage with good aesthetic results, and it is also recommended that patients who had the indications for combined immediate breast augmentation after removal to rebuild the breast appearance.

Simultaneous dual-color calcium imaging in freely-behaving mice.

Miniaturized fluorescence microscopes (miniscopes) enable imaging of calcium events from a large population of neurons in freely behaving animals. Traditionally, miniscopes have only been able to record from a single fluorescence wavelength. Here, we present a new open-source dual-channel Miniscope that simultaneously records two wavelengths in freely behaving animals. To enable simultaneous acquisition of two fluorescent wavelengths, we incorporated two CMOS sensors into a single Miniscope. To validate our dual-channel Miniscope, we imaged hippocampal CA1 region that co-expressed a dynamic calcium indicator (GCaMP) and a static nuclear signal (tdTomato) while mice ran on a linear track. Our results suggest that, even when neurons were registered across days using tdTomato signals, hippocampal spatial coding changes over time. In conclusion, our novel dual-channel Miniscope enables imaging of two fluorescence wavelengths with minimal crosstalk between the two channels, opening the doors to a multitude of new experimental possibilities. Teaser: Novel open-source dual-channel Miniscope that simultaneously records two wavelengths with minimal crosstalk in freely behaving animals.

Research on the mechanism of sea buckthorn leaf Fu tea in the treatment of hyperlipidemia.

Background: Hyperlipidemia (HLP) presents a significant challenge to global public health. Mounting evidence suggests that statins, the recommended first-line lipid-lowering agents, have significant adverse effects. Consequently, the quest for natural and efficacious alternative therapies is steadily emerging as a research priority for HLP prevention and treatment. Consumption of tea, which is rich in diverse biologically active compounds with the capacity to regulate lipid metabolism and combat obesity, has emerged as a promising alternative therapy. Sea buckthorn leaves are rich in a multitude of biologically active substances, have a hypolipidemic effect, and can be used as a raw material for tea because of their unique flavor. There is a suggestion that combining Aspergillus cristatus with tea could modify or boost the lipid-lowering active compounds present in tea, thereby increasing its efficacy in regulating lipid metabolism. Results: Sea Buckthorn Leaf Fu Tea (SBLFT) was obtained by fermentation when sea buckthorn leaves contained 42 % moisture, inoculated with Aspergillus cristatus 0.2 mL/g, and incubated for 8 d at constant temperature. Animal experiments demonstrated that SBLFT significantly inhibited body weight gain in HLP rats and reduced lipid content and serum oxidative stress. In addition, liver tissue sections and functional indices showed that SBLFT can improve liver morphology and function abnormalities. Reverse transcription-polymerase chain reaction results indicated that the expression of Liver kinase B1 (LKB1), adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), acetyl CoA carboxylase 1 (ACC1), and sterol-regulatory element binding protein-1 (SREBP1c) gene related to lipid metabolism was altered. Conclusion: SBLFT improved HLP, specifically via promoting the expression of LKB1 in the liver of HLP rats, activating AMPK, and inhibiting ACC1 and SREBP1c expression, resulting in the inhibition of fatty acid and triglyceride synthesis-related enzymes at the transcriptional level.

Netrin-1 Is an Important Mediator in Microglia Migration.

Microglia migrate to the cerebral cortex during early embryonic stages. However, the precise mechanisms underlying microglia migration remain incompletely understood. As an extracellular matrix protein, Netrin-1 is involved in modulating the motility of diverse cells. In this paper, we found that Netrin-1 promoted microglial BV2 cell migration in vitro. Mechanism studies indicated that the activation of GSK3ß activity contributed to Netrin-1-mediated microglia migration. Furthermore, Integrin α6/ß1 might be the relevant receptor. Single-cell data analysis revealed the higher expression of Integrin α6 subunit and ß1 subunit in microglia in comparison with classical receptors, including Dcc, Neo1, Unc5a, Unc5b, Unc5c, Unc5d, and Dscam. Microscale thermophoresis (MST) measurement confirmed the high binding affinity between Integrin α6/ß1 and Netrin-1. Importantly, activation of Integrin α6/ß1 with IKVAV peptides mirrored the microglia migration and GSK3 activation induced by Netrin-1. Finally, conditional knockout (CKO) of Netrin-1 in radial glial cells and their progeny led to a reduction in microglia population in the cerebral cortex at early developmental stages. Together, our findings highlight the role of Netrin-1 in microglia migration and underscore its therapeutic potential in microglia-related brain diseases.

Single-cell sequencing reveals the correlation of aggrephagy signaling and multiple myeloma immune microenvironment composition.

Aggrephagy, a type of autophagy, degrades the aggregation of misfolded protein in cells. However, the role of aggrephagy in multiple myeloma (MM) has not been fully demonstrated. In this study, we first investigated the correlation between aggrephagy signaling, MM immune microenvironment composition and disease prognosis. Single-cell RNA-seq data, including the expression profiles of 12,187 single cells from seven MM bone marrow (BM) and seven healthy BM samples, were analyzed by non-negative matrix factorization for 44 aggrephagy-related genes. Bulk RNA-seq cohorts from the Gene Expression Omnibus database were used to evaluate the prognostic value of aggrephagy-related immune cell subtypes and predict immune checkpoint blockade immunotherapeutic response in MM. Compared with healthy BM, MM BM exhibited different patterns of aggrephagy-related gene expression. In MM BM, macrophages, CD8+ T cells, B cells and natural killer cells could be grouped into four to nine aggrephagy-related subclusters. The signature of aggrephagy signaling molecule expression in the immune cells correlates with the patient's prognosis. Our investigation provides a novel view of aggrephagy signaling in MM tumor microenvironment cells, which might be a prognostic indicator and potential target for MM treatment.

Metabolic remodeling by RNA polymerase gene mutations is associated with reduced ß-lactam susceptibility in oxacillin-susceptible MRSA.

The emergence of oxacillin-susceptible methicillin-resistant Staphylococcus aureus (OS-MRSA) has imposed further challenges to the clinical management of MRSA infections. When exposed to ß-lactam antibiotics, these strains can easily acquire reduced ß-lactam susceptibility through chromosomal mutations, including those in RNA polymerase (RNAP) genes such as rpoBC, which may then lead to treatment failure. Despite the increasing prevalence of such strains and the apparent challenges they pose for diagnosis and treatment, there is limited information available on the actual mechanisms underlying such chromosomal mutation-related transitions to reduced ß-lactam susceptibility, as it does not directly associate with the expression of mecA. This study investigated the cellular physiology and metabolism of six missense mutants with reduced oxacillin susceptibility, each carrying respective mutations on RpoBH929P, RpoBQ645H, RpoCG950R, RpoCG498D, RpiAA64E, and FruBA211E, using capillary electrophoresis-mass spectrometry-based metabolomics analysis. Our results showed that rpoBC mutations caused RNAP transcription dysfunction, leading to an intracellular accumulation of ribonucleotides. These mutations also led to the accumulation of UDP-Glc/Gal and UDP-GlcNAc, which are precursors of UTP-associated peptidoglycan and wall teichoic acid. Excessive amounts of building blocks then contributed to the cell wall thickening of mutant strains, as observed in transmission electron microscopy, and ultimately resulted in decreased susceptibility to ß-lactam in OS-MRSA. IMPORTANCE: The emergence of oxacillin-susceptible methicillin-resistant Staphylococcus aureus (OS-MRSA) strains has created new challenges for treating MRSA infections. These strains can become resistant to ß-lactam antibiotics through chromosomal mutations, including those in the RNA polymerase (RNAP) genes such as rpoBC, leading to treatment failure. This study investigated the mechanisms underlying reduced ß-lactam susceptibility in four rpoBC mutants of OS-MRSA. The results showed that rpoBC mutations caused RNAP transcription dysfunction, leading to an intracellular accumulation of ribonucleotides and precursors of peptidoglycan as well as wall teichoic acid. This, in turn, caused thickening of the cell wall and ultimately resulted in decreased susceptibility to ß-lactam in OS-MRSA. These findings provide insights into the mechanisms of antibiotic resistance in OS-MRSA and highlight the importance of continued research in developing effective treatments to combat antibiotic resistance.

Biochemical insights into proline metabolism and its contribution to the endurant cell wall structure under metal stress.

The cell wall serves as the primary barrier against the entry of heavy metal ions into cells. However, excessive accumulation of heavy metals within plants can lead to alterations in the spatial structure and physical properties of the cell wall, thereby affecting the capacity of plants to capture heavy metals. Proline (Pro) is involved in the synthesis of the cell wall, modulating the stability and integrity of its structure. Extensins, core proteins that maintain the cell wall structure, are proline/hydroxyproline-rich glycoproteins that contain the characteristic sequence Ser-[Pro]3-5. They act as intermediates in the regulation of biological processes such as cell wall synthesis, assembly, and signal transduction, typically forming a network structure of cell wall proteins through cross-linking with pectin. This network is essential for the self-assembly expansion of the plant cell wall and plays an indispensable role in cell wall stress signal transduction through its interaction with intracellular signalling molecules. However, the mechanisms by which Pro affects the synthesis of cell wall structural proteins, cell wall assembly, and the sensing of cell wall stress under heavy metal stress remain unclear. This review, from the perspectives of biochemistry and molecular biology, comprehensively elaborates on the impact of Pro and Pro-rich proteins on the structure and function of the cell wall. These findings emphasize the mechanism by which Pro enhances the ability of the cell wall to capture heavy metals, providing new research ideas for the use of genetic engineering to manipulate cell wall synthesis and repair, thereby reducing the phytotoxicity of heavy metals.

Novel Reactive Polyhedral Oligomeric Silsesquioxane-Reinforced and Toughened Epoxy Resins for Advanced Composites.

Most toughening methods for epoxy resins are usually used at the expense of other properties. Some polyhedral oligomeric silsesquioxanes (POSSs) with both a rigid Si-O-Si structure and flexible organic chain segments could be expected to be effective toughening agents. In this study, three reactive polyhedral oligomeric silsesquioxanes with a thiol group (OMPPS), a carboxyl group (OCOPS), and an epoxy group (OGCPS) were synthesized and characterized. They were utilized as modifiers to toughen 3-(oxiran-2-ylmethoxy)-N,N-bis(oxiran-2-ylmethyl)aniline (AFG-90MH)/4,4'-methylenebis(2-ethylaniline) (MOEA) (epoxy resin) with different molar ratios to obtain hybrid resins named OMPPS-EP-i, OCOPS-EP-j, and OGCPS-EP-k. The effects of the amount of modifier added and the length of the organic chain on the cage structure on various properties of the hybrid resins were investigated. The results show that all three modifiers show good compatibility with the epoxy resin. The hybrid resins have a low viscosity at 45~85 °C and can be cured at a low temperature (110 °C). The cured hybrid resins display improved toughness. Typically, the critical stress intensity factor (KIC) and impact strength of OGCPS-EP-0.6-C are 2.54 MPa∙m-1/2 and 19.33 kJ∙m-2, respectively, which increased by 58.75% and 22.48% compared with the pristine epoxy resin, respectively. In addition, the glass transition temperature and flexural strength of the hybrid resins are basically unchanged.

Study on the enhanced efficacy mechanism of vinegar-processed Cyperus rotundus in the treatment of primary dysmenorrhea.

The enhanced efficacy of vinegar-processed Cyperus rotundus (VCR) in treating primary dysmenorrhea (PD) has been observed. However, the active components and potential mechanisms of synergy are still unclear. The objective of this study was to develop a method that combines bionic technology, plant metabolomics and network pharmacology to discover the active components and potential mechanisms underlying the enhanced therapeutic effects of VCR for PD. Vinegar processing alters the flavor of C. rotundus, leading to changes in its properties. The acidic nature of vinegar enhances the selectivity of the medicine toward the liver, thereby improving its ability to soothe the liver, regulate qi and provide pain relief. Through gas chromatography-mass spectrometry and multivariate statistical analysis, 30 key differential components between raw C. rotundus and VCR have been screened and identified. These differential components primarily exert their therapeutic effects in treating PD by modulating targets such as interleukin-6, TNF, TP53 and PTGS2, as well as pathways including the estrogen signaling pathway, ovarian steroidogenesis, the TNF signaling pathway and the HIF-1 signaling pathway. The findings of this study serve as a reference for the application of VCR in compound formulas and clinic practiceal. Furthermore, the methodology employed in this study provides research insights for the processing of other Chinese medicines.

Genomic characterization revealing the high rate of tet(X4)-positive Escherichia coli in animals associated with successful genetic elements.

Introduction: The rapid spread of plasmid-mediated tet(X4) conferring high tigecycline resistance poses a significant threat to public health. Escherichia coli as the most common pathogen which carries tet(X4) has been widely disseminated in China. Thus, comprehensive investigations are required to understand the mechanism of transmission of tet(X4)-positive E. coli. Methods: In this study, a total of 775 nonduplicate samples were collected in Guangdong, China from 2019 to 2020. We screened for tet(X4)-positive E. coli by PCR amplification and species identification. Furthermore, we analyzed the phylogenetics and genetic context of tet(X4)-positive E. coli through whole-genome sequencing and long-reads sequencing. Results: Overall, 146 (18.84%) tet(X4)-positive E. coli were isolated, comprising 2 isolates from humans and 144 isolates from pigs. The majority of tet(X4)-positive E. coli exhibited resistance to multiple antibiotics but all of them were susceptible to amikacin and colistin. Phylogenetic analysis showed that ST877, ST871, and ST195 emerged as the predominant sequence types in tet(X4)-positive E. coli. Further analysis revealed various genetic environments associated with the horizontal transfer of tet(X4). Notably, a 100-kbp large fragment insertion was discovered downstream of tet(X4), containing a replicon and a 40-kbp gene cluster for the bacterial type IV secretion system. Discussion: The high colonization rate of tet(X4)-positive E. coli in animals suggests that colonization as a key factor in its dissemination to humans. Diverse genetic context may contribute to the transfer of tet(X4). Our findings underline the urgent need for controlling the spread of plasmid-mediated tigecycline resistance.

Leveraging High-Resolution Ion Mobility-Mass Spectrometry for Cyclic Peptide Soft Spot Identification.

Cyclic peptides are an important class of molecules that gained significant attention in the field of drug discovery due to their unique pharmacological characteristics and enhanced proteolytic stability. Yet, gastrointestinal degradation remains a major hurdle in the discovery of orally bioavailable cyclic peptides. Soft spot identification (SSID) of the regions in the cyclic peptide sequence susceptible to amide hydrolysis by proteases is used in the discovery stage to guide medicinal chemistry design. SSID can be an arduous task, traditionally performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), often resulting in complex and time-consuming manual analysis, particularly when isomeric linear peptide metabolites chromatographically coelute. Here, we present an alternative orthogonal approach that entails a high-resolution ion mobility (HRIM) system based on Structures for Lossless Ion Manipulation (SLIM) technology interfaced with quadrupole time-of-flight (QTOF) mass spectrometry to address some of the challenges associated with SSID. Two strategies were used to resolve linear isomeric peptide metabolites: labeled and label-free, both utilizing the HRIM platform. The label-free strategy leverages negative polarity to ionize the isomers which achieves better separation of the gas phase ions in the ion mobility (IM) dimension as compared to positive polarity, which is a more conventional approach when studying proteins and peptides. The second approach uses an isotope-labeled dimethyl tag on the terminal amine group, acting as a "shift reagent" to influence the mobility of isomers in the positive mode. This method resulted in baseline separation for the isomers of interest and produced unique product ions in the fragmentation spectra for unambiguous soft spot identification. Both label-free and labeled strategies demonstrated the ability to solve the challenges associated with SSID for cyclic peptides.