Chromosome recombination and modification by LoxP-mediated evolution in Vibrio natriegens using CRISPR-associated transposases.

Chromosome rearrangement by LoxP-mediated evolution has emerged as a powerful approach to studying how chromosome architecture impacts phenotypes. However, it relies on the in vitro synthesis of artificial chromosomes. The recently reported CRISPR-associated transposases (CASTs) held great promise for the efficient insertion of abundant LoxP sites directly onto the genome of wild-type strains. In this study, with the fastest-growing bacterium Vibrio natrigens (V. natriegens) as an object, a multiplex genome integration tool derived from CASTs was employed to achieve the insertion of cargo genes at eight specific genomic loci within 2 days. Next, we introduced 30 LoxP sites onto chromosome 2 (Chr2) of V. natriegens. Rigorously induced Cre recombinase was used to demonstrate Chromosome Rearrangement and Modification by LoxP-mediated Evolution (CRaMbLE). Growth characterization and genome sequencing showed that the ~358 kb fragment on Chr2 was accountable for the rapid growth of V. natriegens. The enabling tools we developed can help identify genomic regions that influence the rapid growth of V. natriegens without a prior understanding of genome mechanisms. This groundbreaking demonstration may also be extended to other organisms such as Escherichia coli, Pseudomonas putida, Bacillus subtilis, and so on.

Application and development of zero-valent iron (ZVI)-based materials for environmental remediation: A scientometric and visualization analysis.

Zero-valent iron (ZVI)-based materials are among the most widely used engineered particles in the field of environmental remediation. To provide a comprehensive overview of the status and trend of the research on them, this study conducted a quantitative and visual analysis of 6296 relevant publications obtained from Web of Science between 1994 and 2022 using CiteSpace software. By using the bibliometric method, this work systematically analyzed the knowledge structure, research hotspots and trends of ZVI-based materials in this field. The results show that the research on ZVI-based materials in this field developed rapidly over the past 28 years. China is the greatest contributor with the most published articles and collaborations. Still, the USA has the most academic influence with the highest average citations per article. Chinese Academy of Sciences and Tongji University are the primary establishments that produced the greatest number of publications and had the highest h-index. Keyword cluster analysis indicates that the primary research topics are related to reductive dechlorination, sulfate radical, arsenic removal, graphene oxide, porous media, peroxymonosulfate, groundwater remediation, and permeable reactive barrier. Meanwhile, keyword burst analysis reveals that the primary research hotspots and frontiers of ZVI focus on its modification, the refractory and emerging contaminants treatment, persulfate activation, and electron transfer. However, no keywords or topics related to the environmental impact and toxicity of ZVI-based materials are available in the keyword clustering and burst analysis results, indicating this direction deserves more attention in future research. Through a comprehensive and in-depth bibliometric analysis, this paper provides new insight into the research hotspots and development trends of the research on ZVI-based materials in environmental remediation.

Molecular detection and characterization of three novel parvoviruses belonging to two different subfamilies in zoo birds.

Birds carry a large number of viruses that may cause diseases in animals or humans. At present, information about the virome of zoo birds is limited. In this study, using viral metagenomics, we investigated the fecal virome of zoo birds collected from a zoo in Nanjing, Jiangsu Province, China. Three novel parvoviruses were obtained and characterized. The genomes of the three viruses are 5,909, 4,411, and 4,233 nt in length, respectively, and contain four or five ORFs. Phylogenetic analysis showed that these three novel parvoviruses clustered with other strains and formed three different clades. Pairwise comparison of NS1 amino acid sequences showed that Bir-01-1 shared 44.30-74.92% aa sequence identity with other parvoviruses belonging to the genus Aveparvovirus, while Bir-03-1 and Bir-04-1 shared less than 66.87% and 53.09% aa sequence identity, respectively, with other parvoviruses belonging to the genus Chaphamaparvovirus. Each of these three viruses was identified as a member of a novel species based on the species demarcation criteria for parvoviruses. These findings broaden our knowledge of the genetic diversity of parvoviruses and provide epidemiological data regarding potential outbreaks of parvovirus disease in birds.

Comparison of mothers' perceptions of hunger cues in 3-month-old infant under different feeding methods.

BACKGROUND: Mothers' perception of infant hunger cues is a critical content of responsive feeding, which is central to the promotion of early childhood development. However, only a few studies have examined responsive feeding in China, especially lacking the studies on perceptions of infant hunger cues. Consider the cultural differences, the aim of this study was to describe the perceptions of infant hunger cues of Chinese mothers for infants aged 3 months, and explore the relationship between maternal perceptions of infant hunger cues and different feeding methods. METHODS: A cross-sectional study was conducted with a sample of 326 mothers of healthy 3-month-old infants, including 188 exclusive breastfeeding (EBF) mothers and 138 formula feeding (FF) mothers. It was implemented in four provincial and municipal maternal and child health hospitals. The mothers' perceptions of infant hunger cues were surveyed by self-reporting questionnaires. Chi-square tests and logistic analysis were applied to analyze the differences in maternal perceptions of infant hunger cues, including the number of hunger cues and the specific cues, between EBF group and FF group by controlling sociodemographic variables and the daily nursing indicators. RESULTS: We found that a higher proportion of EBF mothers could perceive multiple hunger cues (≥ 2) than FF mothers (66.5% vs.55.1%). For specific cues, the EBF mothers had higher perceptions of infant's "hand sucking" (67.6% vs. 53.6%) and "moving head frantically from side to side" (34.6% vs. 23.9%), all p < 0.05. Regression analysis revealed that EBF might support mothers to perceive infant hunger cues than FF mothers, with the number of infant hunger cues (OR = 1.70, 95% CI: 1.01-2.85), "hand sucking" (OR = 1.72, 95% CI: 1.04-2.87), "moving head frantically from side to side" (OR = 2.07, 95% CI: 1.19-3.62). The number of infant hunger cues perceived by mothers was also associated with their educational level and family structure. CONCLUSION: EBF mothers of 3-month-old infants may be more likely to perceive infant hunger cues than FF mothers in China. It is necessary to increase the health education about infant hunger and satiety cues to caregivers in China, especially among mothers with lower education levels, mothers living in nuclear families, and FF mothers.

Stress Monitoring of Segment Structure during the Construction of the Small-Diameter Shield Tunnel.

Segmental stress during the construction process plays a pivotal role in assessing the safety and quality of shield tunnels. Fiber Bragg grating (FBG) sensing technology has been proposed for tunnel segment stress monitoring. A laboratory test was conducted to validate the reliable strain measurement of FBG sensors. The field in situ monitoring of a sewerage shield tunnel was carried out to examine the longitudinal and circumferential stresses experienced by the segments throughout the construction phase. The cyclic fluctuations in stress were found to be synchronized with the variations in shield thrust. A comparison was made between the longitudinal and circumferential stress variations observed during the shield-driving and segment-assembly processes. Additionally, the time required for the grouting to reach its full curing strength was estimated, revealing its impact on the stress levels and range of the pipe segment. The findings of this study offer an enhanced understanding of the stress state and health condition of small-diameter shield tunnels, which can help in optimizing the design and construction process of tunnel segments, as well.

Suppressing scattering-induced nanosecond pre-pulses in Ti:sapphire multi-pass amplifiers.

In this Letter, we experimentally investigate a new kind of nanosecond pre-pulse, which originates from the bidirectional scattering of crystals in traditional Ti:sapphire multi-pass amplifiers. The experimental results demonstrate that the intensity of scattering-induced pre-pulses is very sensitive to the scattering angle, and the delay time between the pre-pulse and the main pulse is an integer multiple of the light path in each pass of the amplifier. An optimized multi-pass amplifier configuration is proposed, for what is believed to be the first time, to suppress the scattering-induced pre-pulses. The contrast ratio between pre-pulses and the main pulse is enhanced by more than two orders of magnitude, reaching a level of 10-10. This novel multi-pass amplifier configuration is very simple and economical, and provides an effective solution for the temporal contrast enhancement in the nanosecond range.

Me-Better Drug Design Based on Nevirapine and Mechanism of Molecular Interactions with Y188C Mutant HIV-1 Reverse Transcriptase.

In this paper, the Y188C mutant HIV-1 reverse transcriptase (Y188CM-RT) target protein was constructed by homology modeling, and new ligands based on nevirapine (NVP) skeleton were designed by means of fragment growth. The binding activity of new ligands to Y188CM-RT was evaluated by structural analysis, ADMET prediction, molecular docking, energy calculation and molecular dynamics. Results show that 10 new ligands had good absorbability, and their binding energies to Y188CM-RT were significantly higher than those of wild-type HIV-1 reverse transcriptase(wt). The binding mode explained that fragment growth contributed to larger ligands, leading to improved suitability at the docking pocket. In the way of fragment growth, the larger side chain with extensive contact at terminal is obviously better than substituted benzene ring. The enhancement of docking activity is mainly due to the new fragments such as alkyl chains and rings with amino groups at NVP terminal, resulting in a large increase in hydrophobic bonding and the new addition of hydrogen bonding or salt bonding. This study is expected to provide reference for the research on non-nucleoside reverse transcriptase inhibitors resistance and AIDS treatment.

Hypoperfusion in nucleus accumbens in chronic migraine using 3D pseudo-continuous arterial spin labeling imaging MRI.

BACKGROUND: Nucleus accumbens (NAcc) played an important role in pain mediation, and presents changes of neuronal plasticity and functional connectivity. However, less is known about altered perfusion of NAcc in chronic migraine (CM). The aim of this study is to investigate the altered perfusion of the NAcc in CM using a MR three-dimensional pseudo-continuous arterial spin labeling (3D PCASL) imaging. METHODS: Thirteen CM patients and 15 normal controls (NC) were enrolled and underwent 3D PCASL and brain structural imaging. The cerebral blood flow (CBF) images were co-registered with the brain structural images, and the volume and CBF value of NAcc were extracted from the raw brain structural images and co-registered CBF images using an individual NAcc mask, which was obtained from the AAL3 template under transformation by the inverse deformation field generated from the segmentation of the brain structural images. The independent sample t test and receiver operating characteristic (ROC) curve was used to investigate the altered volume and perfusion of the NAcc in CM patients. RESULTS: There was no significant difference for the volume of bilateral NAccs between CM and NC (p > 0.05). CM presented a lower CBF value (49.34 ± 6.09 ml/100 mg/min) compared with that of NC (55.83 ± 6.55 ml/100 mg/min) in left NAcc (p = 0.01), while right NAcc showed no significant difference between CM and NC (p = 0.11). ROC analysis identified that the area under the curve was 0.73 (95CI% 0.53-0.88) with cut-off value 48.63 ml/100 mg/min with sensitivity 50.00% and specificity 93.33%. The correlation analysis found a negative correlation between the CBF value of the left NAcc and VAS score (r = -0.61, p = 0.04). CONCLUSION: Hypoperfusion of the left NAcc was observed in CM, which could be considered as a potential diagnostic imaging biomarker in CM.

Measurement algorithm for real front and back curved surfaces of contact lenses.

The optical measurement algorithm for the real front and back surfaces of contact lenses from their center to periphery accurately and simultaneously is proposed. It is an algorithm that makes light incident vertically along the curved surfaces of contact lenses under the condition that the difference of curvature radii between the front and back surfaces is small enough within the NA of the optical probe. For this purpose, we adopted time-domain optical coherence tomography (OCT) with translation and rotation mechanisms. The shape, thickness distribution, and curvature radii of both surfaces were estimated with OCT signal analysis and circular approximation. The measured results were compared with the designed values and the measured data from a conventional shape measurement device. The curved shape of both surfaces and thickness were well matched with the designed values from lens center to periphery. In a curvature radius of the front surface, there was a proportional bias with a limit of agreement of -0.77% to -2.09%, and the correlation coefficient was 0.57. On the back surface, there was no systematic bias, and minimal detectable change was 0.178 mm, in a range of 95% confidential interval. The proposed algorithm well visualized the real shape and optical characteristics of the contact lens with enough accuracy to the design.

Application of FBG Sensing Technology in Stability Analysis of Geogrid-Reinforced Slope.

By installing FBG sensors on the geogrids, smart geogrids can both reinforce and monitor the stability for geogrid-reinforced slopes. In this paper, a geogrid-reinforced sand slope model test is conducted in the laboratory and fiber Bragg grating (FBG) sensing technology is used to measure the strain distribution of the geogrid. Based on the model test, the performance of the reinforced soil slope is simulated by finite element software Midas-GTS, and the stability of the reinforced soil slope is analyzed by strength reduction method. The relationship between the geogrid strain and the factor of safety is set up. The results indicate that the measured strain and calculated results agree very well. The geogrid strain measured by FBG sensor can be applied to evaluate the stability of geogrid-reinforced sand slopes.

Dynamic characteristics of a coaxial magnetic switch modulating pulse forming networks.

Pulsed power generators utilizing magnetic switch technology within the 100 ns scale have become widespread for surface treatment, high power microwave generation, and food processing, in which the dynamic characteristics of the magnetic switch perform an important function. The saturation process, electric field between layers, and energy loss are closely associated with the applied time scale of the magnetic core, which affects the dynamic characteristics of the switch. However, compared with the study within the microsecond scale, the dynamic characteristics of magnetic switches within the 100 ns scale have not been studied in depth. In this paper, the dynamic characteristics of a coaxial magnetic switch modulating pulse forming networks (PFNs) are studied via both field-loop co-simulation and scaled experimental test. It is found that increasing PFN section number (Ns) leads to an acceleration in the saturation process of the core, which helps understand the switch performance of the magnetic core more clearly. With respect to a specific magnetic switch based on a ferromagnetic core, it is quantitatively analyzed that increasing Ns from 1 to 10 leads to a 16.1% reduction in core saturation time (tsat), a 13.4% increase in eddy loss (EET), and a 5.7% rise in maximum interlamination field strength (Emax) under the 100 ns scale; however, tsat is reduced by 19.3%, EET increases by 5.2%, and Emax rises by 2.3% under the microsecond scale. The results could provide a design reference for magnetic switches in pulsed power generators.

Study on a rotational symmetry structure pulse forming network with low-impedance for compact pulse drivers.

A pulse forming network (PFN) is a significant component, contributing a lot to the overall dimension of pulse generators. In order to both reduce the size of PFN and improve the output waveform quality, this paper proposes a compact low-impedance PFN with a rotational symmetry structure. The PFN consists of four groups of Blumlein pulse forming units (PFUs) connected in parallel along the angular direction, and the spline curve structure is applied in each PFU, which achieves a higher space utilization rate. The theoretical maximum energy density of PFN is 6.6 J/L as the dimensions of PFN are φ500 × 138 mm. Field-circuit co-simulation is carried out based on the spatial model of PFN and the double switch modulation circuit to analyze the effects of switch delay time (time between main switch and steep discharge switch), as well as the output port position affecting the output pulse waveform. The results show that the PFN is appropriate to achieve quasi-square wave pulse modulation as the switch delay time is 290 ns with the output port positioned at the periphery. The verification experiments are also carried out. The results show that the PFN can generate a quasi-square wave pulse with an output voltage of 49.6 kV, a pulse width of 83 ns, and a peak power of 1 GW on a matched load. The output pulse exhibits a distinct flat top, with the fluctuation of the plateau being less than 3%.

Driving factors of spatial-temporal difference in China's transportation sector carbon productivity: an empirical analysis based on Geodetector method.

Carbon productivity is the core index to measure the performance of carbon emission reduction. Exploring the driving factors of the spatial-temporal differences in China's transportation sector, carbon productivity (TSCP) is conducive to the low-carbon sustainable development of the transportation sector. Based on the calculation of TSCP in 30 provinces in China from 2000 to 2019, we use time series, spatial visualization, and Dagum Gini coefficient to reveal the characteristics of spatial-temporal evolution and regional differences of TSCP, and uses Geodetector to identify the driving factors that affecting the spatial-temporal differences of TSCP. The results are as follows: (1) from 2000 to 2019, China's TSCP shows a U-shaped change trend of "decline to rise," and shows a spatial pattern of "high in the eastern and central, low in the western". (2) There are obvious regional differences in China's TSCP. The differences within each region show the trend of "eastern > central > western," while the differences between regions show the trend of "central-western > eastern-western > eastern-central," and the differences between regions are the main reason for the overall differences. (3) The spatial-temporal differences in China's TSCP are affected by many factors, such as social economy and self-endowment. Overall, energy intensity, foreign trade, technological innovation level, energy structure, and industrial structure are the dominant factors. Additionally, the interaction between the driving factors enhances the impact on the spatial-temporal differences of TSCP. Finally, according to the analysis results, some policy suggestions are put forward to improve TSCP.

Recombinant Protein Expression Chassis Library of Vibrio natriegens by Fine-Tuning the Expression of T7 RNA Polymerase.

Vibrio natriegens is the fastest-growing bacteria, and its doubling time is less than 10 min. At present, the T7 expression system has been introduced into V. natriegens for heterologous protein expression, including the commercial strain Vmax1 and the variant VnDX,2 which is a backup expression chassis of Escherichia coli BL21(DE3). However, the strength of the existing T7 expression system is not optimal for every recombinant protein. The different expression strengths of T7 RNA polymerase (T7 RNAP) can be obtained by changing the promoter and ribosome binding site (RBS) sequences of T7 RNAP at different transcription and translation levels. In this work, we obtained a robust VnDX variant library with the fine-tuning T7 RNAP using the industrially used enzyme glucose dehydrogenase (GDH) as the reporter protein. Among this library, the variant VnDX-tet, whose promoter of T7 RNAP was changed from PlacUV5 to Ptet, showed that the reporter enzyme GDH activity was increased by 109% by the T7 expression system. Similarly, variants with different T7 RNAP translation levels were obtained by changing RBS sequences upstream of T7 RNAP, and the results showed that the variant VnDX-RBS12/pGDH had the highest GDH activity, which increased by 12.6%. The VnDX variant library constructed in this study with different T7 expression strengths provides a choice for expressing various recombinant proteins, greatly expanding the application of V. natriegens.

Current Progress and Outlook for Agrimonolide: A Promising Bioactive Compound from Agrimonia pilosa Ledeb.

Agrimonolide (AM), which is a derivative of isocoumarins, is found mainly in the herb Agrimonia pilosa Ledeb. This compound is highly lipophilic and readily crosses the blood-brain barrier. In recent years, interest has grown in the use of AM as a multitarget natural treatment for various diseases, such as cancer, inflammation, hepatic injury, myocardial damage, and diabetes mellitus. The potential mechanisms of these pharmacological effects have been clarified at cellular and molecular levels. AM shows no cytotoxicity over a range of concentrations in different types of cells, providing evidence for its good safety profile in vitro. These findings indicate that AM is a promising medicinal agent. However, most studies on AM's pharmacological activities, mechanisms of action, and safety lack substantial animal or human data. Additionally, the pharmacokinetics, metabolism, and disposition of this compound have received little attention. This review highlights the status of current information regarding the sources, properties, pharmacological effects, and safety of AM. Furthermore, potential strategies to resolve problematic issues identified in previous studies are fully discussed. This summary and analysis of the research progress of AM may inspire deeper investigations and more extensive applications of AM in the future.

Molecular detection and characterization of three novel parvoviruses belonging to two different subfamilies in zoo birds.

Birds carry a large number of viruses that may cause diseases in animals or human. At present, virome of zoo birds are limited. In this study, using viral metagenomics method, we investigated the feces virome of zoo birds collected from a zoo of Nanjing, Jiangsu Province, China. Three novel parvoviruses were obtained and characterized. The genome of the three viruses are 5,909 bp, 4,411 bp and 4,233 bp in length respectively which encoded four or five ORFs. Phylogenetic analysis indicated that these three novel parvoviruses clustered with other strains formed three different clades. Pairwise comparison of NS1 amino acid sequences showed that Bir-01-1 shared 44.30%-74.92% aa sequence identity with other parvoviruses belonging to the genus Aveparvovirus, while Bir-03-1 and Bir-04-1 had lower than 66.87% and 53.09% aa sequence identity with other parvoviruses belonging to the genus Chaphamaparvovirus. These three viruses were identified as three novel species of the genus Aveparvovirus and Chaphamaparvovirus respectively basing on the species demarcation criteria of parvovirus. Our findings broaden the knowledge of the genetic diversity of parvovirus and provide epidemiological data for the outbreak of potential bird’s parvovirus disease.

CRISPR/Cas9-mediated SNAC9 mutants reveal the positive regulation of tomato ripening by SNAC9 and the mechanism of carotenoid metabolism regulation.

NAC transcriptional regulators are crucial for tomato ripening. Virus-induced gene silencing (VIGS) of SNAC9 (SlNAC19, Gene ID: 101248665) affects tomato ripening, and SNAC9 is involved in ethylene and abscisic acid (ABA) metabolic pathways. However, the function of SNAC9 in pigment metabolism in tomatoes remains unclear. This work seeks to discover the mechanism of SNAC9 involvement in pigment metabolism during tomato ripening by establishing a SNAC9 knockout model using CRISPR/Cas9 technology. The results indicated that fruit ripening was delayed in knockout (KO) mutants, and SNAC9 mutation significantly affected carotenoid metabolism. The chlorophyll (Chl) degradation rate, total carotenoid content, and lycopene content decreased significantly in the mutants. The transformation rate of chloroplasts to chromoplasts in mutants was slower, which was related to the carotenoid content. Furthermore, SNAC9 changed the expression of critical genes (PSY1, PDS, CRTISO, Z-ISO, SGR1, DXS2, LCYE, LCYB, and CrtR-b2) involved in pigment metabolism in tomato ripening. SNAC9 knockout also altered the expression levels of critical genes involved in the biosynthesis of ethylene and ABA. Accordingly, SNAC9 regulated carotenoid metabolism by directly regulating PSY1, DXS2, SGR1, and CrtR-b2. This research provides a foundation for developing the tomato ripening network and precise tomato ripening regulation.

Comprehensive prognostic modeling of locoregional recurrence after radiotherapy for patients with locoregionally advanced hypopharyngeal squamous cell carcinoma.

Purpose: To propose and evaluate a comprehensive modeling approach combing radiomics, dosiomics and clinical components, for more accurate prediction of locoregional recurrence risk after radiotherapy for patients with locoregionally advanced HPSCC. Materials and methods: Clinical data of 77 HPSCC patients were retrospectively investigated, whose median follow-up duration was 23.27 (4.83-81.40) months. From the planning CT and dose distribution, 1321 radiomics and dosiomics features were extracted respectively from planning gross tumor volume (PGTV) region each patient. After stability test, feature dimension was further reduced by Principal Component Analysis (PCA), yielding Radiomic and Dosiomic Principal Components (RPCs and DPCs) respectively. Multiple Cox regression models were constructed using various combinations of RPC, DPC and clinical variables as the predictors. Akaike information criterion (AIC) and C-index were used to evaluate the performance of Cox regression models. Results: PCA was performed on 338 radiomic and 873 dosiomic features that were tested as stable (ICC1 > 0.7 and ICC2 > 0.95), yielding 5 RPCs and DPCs respectively. Three comprehensive features (RPC0, P<0.01, DPC0, P<0.01 and DPC3, P<0.05) were found to be significant in the individual Radiomic or Dosiomic Cox regression models. The model combining the above features and clinical variable (total stage IVB) provided best risk stratification of locoregional recurrence (C-index, 0.815; 95%CI, 0.770-0.859) and prevailing balance between predictive accuracy and complexity (AIC, 143.65) than any other investigated models using either single factors or two combined components. Conclusion: This study provided quantitative tools and additional evidence for the personalized treatment selection and protocol optimization for HPSCC, a relatively rare cancer. By combining complementary information from radiomics, dosiomics, and clinical variables, the proposed comprehensive model provided more accurate prediction of locoregional recurrence risk after radiotherapy.

Identification of Multiple Novel Viruses in Fecal Samples of Black-Necked Cranes Using Viral Metagenomic Methods.

The black-necked crane is the only species of crane that lives in the high-altitude region of the Tibet Plateau. At present, there is little research on viral diseases of the black-necked crane (Grus nigricollis). In this study, a viral metagenomic approach was employed to investigate the fecal virome of black-necked cranes in Saga County, Shigatse City, Tibet, China. The identified virus families carried by black-necked cranes mainly include Genomoviridae, Parvoviridae, and Picornaviridae. The percentages of sequence reads belonging to these three virus families were 1.6%, 3.1%, and 93.7%, respectively. Among them, one genome was characterized as a novel species in the genus Grusopivirus of the family Picornaviridae, four new parvovirus genomes were obtained and classified into four different novel species within the genus Chaphamaparvovirus of the subfamily Hamaparvovirinae, and four novel genomovirus genomes were also acquired and identified as members of three different species, including Gemykroznavirus haeme1, Gemycircularvirus ptero6, and Gemycircularvirus ptero10. All of these viruses were firstly detected in fecal samples of black-necked cranes. This study provides valuable information for understanding the viral community composition in the digestive tract of black-necked cranes in Tibet, which can be used for monitoring, preventing, and treating potential viral diseases in black-necked cranes.

Esculentoside A ameliorates BSCB destruction in SCI rat by attenuating the TLR4 pathway in vascular endothelial cells.

BACKGROUND AND AIMS: Overexpressed MMP-9 in vascular endothelial cells is involved in blood spinal cord barrier (BSCB) dysfunction in spinal cord injury (SCI). Esculentoside A (EsA) has anti-inflammatory and cell protective effects. This study aimed to evaluate its effects on neuromotor function in SCI rats, as well as the potential mechanisms. METHODS: The therapeutic effect of EsA in SCI rats was investigated using Basso-Beattie-Bresnahan (BBB) scores, a grid walk test and histological analyses. To assess the protective role of EsA in the BSCB and in oxygen glucose deprivation/reoxygenation (OGD/R)-induced hBMECs, the BSCB function, tight junctions (TJ) protein (ZO-1 and claudin-5) expression, structure of the BSCB and Matrix metalloproteinase-9 (MMP-9) expression were observed via Evans blue (EB) detection, immunofluorescence analyses and western blotting. Molecular docking simulations and additional experiments were performed to explore the potential mechanisms by which EsA maintains the function of the BSCB in vivo and in vitro. RESULTS: EsA treatment improved BBB scores, reduced cavity formation and the loss of neuronal cells, demonstrating an improvement in motor function in SCI rats. In vivo experiments showed that EsA decreased the infiltration of blood cells and inflammatory mediators (IL-1ß, IL-6 and TNF-α) and protected the structure of TJs in the rat spinal cord and in OGD/R-induced hBMECs. EsA inhibited the activation of Toll-like receptor 4 (TLR4) signalling, which may be related to the protective effect of EsA against MMP-9-induced BSCB damage. CONCLUSIONS: EsA downregulated MMP-9 expression in vascular endothelial cells, protected BSCB function in SCI rats and attenuated TLR4 signalling and thus provide new options for the treatment of SCI.