Responsive Organic Fluorescent Aggregates Based on Ion-π Interactions Away from Fluorescent Conjugated Groups

Responsive organic luminescent aggregates have a wide range of application fields, but currently there is still a lack of reasonable molecular design strategies. Introducing ion-π interactions into molecules can effectively alter their luminescent properties. However, current research typically focuses on ion localization at luminescent conjugated groups with the strong interaction forces. In this work, we introduce the flexible alkoxy chain spacers between fluorescent conjugated groups and ion-π interaction sites, and then adjust the fluorescence performance of the molecule by changing the strength of ion-π interactions. Bromine ion-based molecules with strong ion-π interactions exhibit high and stable fluorescence quantum yields in crystals and amorphous powders under the external stimuli. Hexafluorophosphate ion-based molecules with weak ion-π interactions have the high fluorescence quantum yield in crystals and very low fluorescence quantum yield in amorphous powders, showing variable fluorescence intensities under external stimuli. This demonstrates a new class of responsive organic luminescent solid-state materials.

[Study of the methotrexate loaded extracellular vesicles in the treatment of experimental periodontitis in mice]

Objective: To investigate the therapeutic effect of methotrexate loaded vesicles on experimental periodontitis in mice. Methods: Extracellular vesicles (EVs) were isolated from human umbilical cord mesenchymal stem cells (hUC-MSC). Methotrexate loaded vesicles (MTX-EVs) were constructed, whose morphology and size were analyzed by using scanning electron microscopy and particle size analyzer. Western blotting was used to identify their surface specific proteins. C57BL/6J male mice of 4-5 weeks (provided by Experimental Animal Center of The Fourth Military Medical University) were selected, among which 8 were randomly selected by blind grasp method without treatment and fed normally as normal group, and others were induced to periodontitis models by local injection of lipopolysaccharide (LPS) into the periodontium. The LPS was injected once every day with a concentration of 2 g/L and a volume of 5 μl, lasting for two weeks. The mice with successfully induced periodontitis were randomly divided into 4 groups by blind grasping method, with 8 mice in each group. The LPS group was with no treatment, and the other three groups were treated with periodontal local injection of MTX, EVs or MTX-EVs, respectively. Two weeks later, enzyme-linked immunosorbent assay (ELISA) was used to detect the expressions of inflammatory cytokine interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α) in gingival tissue. The amount of alveolar bone resorption of four groups was detected by using micro-CT scanning and HE staining. The expression proportion of the inflammatory factor in gingival tissue was analyzed by using flow cytometry. Results: The scanning electron microscopy results showed that EVs and MTX-EVs were circular or elliptical in shape. Dynamic light scattering (DLS) particle size analysis showed that the particle size of EVs was around 200 nm, while that of MTX-EVs was around 300 nm. The ELISA results showed IL-1β levels in the normal group, LPS group, LPS+MTX group, LPS+EVs group and LPS+MTX-EVs group were (28.86±2.76), (51.50±2.04), (35.26±2.40), (45.49±2.04) and (35.77±3.49) ng/L. That is, the IL-1β concentrations in the LPS+MTX group, LPS+EVs group and LPS+MTX-EVs group were significantly lower than that in the LPS group (P<0.05); the mass concentration of IL-1β in the LPS +MTX-EVs group was significantly lower than that in the LPS+EVs group (P<0.05). The concentrations of IL-6 in the normal group, LPS group, LPS+MTX group, LPS+EVs group and LPS+MTX-EVs group were (125.44±4.12), (221.64±10.59), (178.16±16.90), (181.09±18.22) and (170.15±9.04) ng/L, among which the concentration of IL-6 in the last three groups were significantly lower than that in the LPS group (P<0.05). The mass concentration of IL-6 in the LPS+MTX-EVs group was significantly lower than those in the LPS+MTX group and LPS+EVs group (P<0.05). The concentrations of TNF-α in the normal group, LPS group, LPS+MTX group, LPS+EVs group and LPS+MTX-EVs group were (320.27±38.68), (479.62±40.94), (342.18±25.89), (415.88±12.01) and (325.75±30.83) ng/L, among which the concentrations of last three groups were significantly lower than the LPS group (P<0.05); the mass concentration of TNF-α in the LPS+MTX-EVs group was significantly lower than those in the LPS+EVs group and LPS+MTX group (P<0.05). The micro-CT results showed that the distance of cement-enamel junction-alveolar bone crest (CEJ-ABC) of the first molar and root (M1R1) in the normal group, LPS group, LPS+MTX group, LPS+EVs group and LPS+MTX-EVs group of mice were (0.11±0.03), (0.28±0.02), (0.23±0.03), (0.20±0.04), and (0.18±0.03) mm, respectively. Compared with the LPS group, the CEJ-ABC of the M1R1 in the LPS+MTX group, LPS+EVs group and LPS+MTX-EVs group were inhibited to varied degrees with statistically significant differences (P<0.05). Among them, LPS+MTX-EVs group had the best bone resorption inhibitioin effect compared to LPS+MTX group and LPS+EVs group, and the differences were statistically significant (P<0.05). The flow cytometry results indicated that the proportion of interferon-γ (IFN-γ) positive cells was (11.77±1.02)% in the LPS group, (6.87±0.65)% in the LPS+EVs group, and (4.15±0.92)% in the LPS+MTX-EVs group, respectively. The proportions of IFN-γ positive cells in the LPS+EVs group and LPS+MTX-EVs group were significantly lower than that in the LPS group (P<0.05), while the ratio of IFN-γ positive cells in the LPS+MTX-EVs group was found significantly lower than that in the LPS+EVs group (P<0.05). Conclusions: MTX-EVs can effectively alleviate the periodontal local inflammatory environment and reduce bone resorption of alveolar bone in periodontitis model mice.

METTL3 Modulates Ctsk+ Lineage Supporting Cranial Osteogenesis via Hedgehog

N6-methyladenosine (m6A) modification, a eukaryotic messenger RNA modification catalyzed by methyltransferase-like 3 (METTL3), plays a pivotal role in stem cell fate determination. Calvarial bone development and maintenance are orchestrated by the cranial sutures. Cathepsin K (CTSK)-positive calvarial stem cells (CSCs) contribute to mice calvarial ossification. However, the role of m6A modification in regulating Ctsk+ lineage cells during calvarial development remains elusive. Here, we showed that METTL3 was colocalized with cranial nonosteoclastic Ctsk+ lineage cells, which were also associated with GLI1 expression. During neonatal development, depletion of Mettl3 in the Ctsk+ lineage cells delayed suture formation and decreased mineralization. During adulthood maintenance, loss of Mettl3 in the Ctsk+ lineage cells impaired calvarial bone formation, which was featured by the increased bone porosity, enhanced bone marrow cavity, and decreased number of osteocytes with the less-developed cellular outline. The analysis of methylated RNA immunoprecipitation sequencing and RNA sequencing data indicated that loss of METTL3 reduced Hedgehog (Hh) signaling pathway. Restoration of Hh signaling pathway by crossing Sufufl/+ alleles or by local administration of SAG21 partially rescued the abnormity. Our data indicate that METTL3 modulates Ctsk+ lineage cells supporting calvarial bone formation by regulating the Hh signaling pathway, providing new insights for clinical treatment of skull vault osseous diseases.

Cu(N2)-Li Battery for Ammonia Synthesis

The cathodic mechanism of Li-N2 batteries is similar to Li-mediated N2 reduction (LiNR). Herein, the Li-N2, LiNR, and Cu-Li battery were amalgamated to a milliliter-scale Cu(N2)-Li system. The utilization of a lithium anode with lithium oxidation reaction (LiOR), ensures an uninterrupted supply of lithium ions to active N2. LiOR not only enhances electrolyte stability but also reduces voltage by stripping Li ions, in contrast to the inert platinum anode, commonly employed in LiNR. Notably, an unusual observation of ammonia accumulation within the anode chamber elucidates the presence and role of reaction intermediates. The charging process aimed at lithium regeneration faces high polarization, and a cycling procedure involving low-current charging was proposed to improve cycling. This study integrates insights from three distinct research directions to leverage their respective advantages and scientific insights. The Li-N2 battery emerges as a highly advantageous strategy for ammonia synthesis due to the progressiveness of lithium anode.

Effect of ursodeoxycholic acid on preventing SARS-CoV-2 infection in patients with liver transplantation: a multicenter retrospective cohort study

BACKGROUND

Immunosuppressed recipients of liver transplantation (LT) are more likely to develop coronavirus disease 2019 (COVID-19) and may have an increased risk of developing worse outcomes.

AIM

To assess the effect of ursodeoxycholic acid (UDCA) on preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in LT recipients.

DESIGN

Adult patients (aged ≥ 18 years) who underwent LT between 1 January 2015 and 31 December 2022 were included and categorized into two groups according to their use of UDCA.

METHODS

The prevalence and severity of COVID-19 among transplantation patients between the UDCA and non-UDCA groups were estimated and compared.

RESULTS

Among the 897 LT patients who met the inclusion criteria, infection rate of SARS-CoV-2 was 78.4%, and the rate of severe illness was 5.1% from January 2022 to January 2023 in China. In the multivariate analysis, only UDCA treatment (P = 0.006) was found to be a protective factor against SARS-CoV-2 infection. After propensity score matching, the SARS-CoV-2 infection rate in the UDCA group was lower than that in the non-UDCA group (74.1% vs. 84.6%, P = 0.002). This rate was further reduced to 62.1% (P = 0.002) when the oral administration dose was >15 mg/kg/day. There was no difference in the rates of severe COVID-19 illness, ICU admission, or ventilation rate or length of hospital stay with or without UDCA treatment (all P > 0.05).

CONCLUSIONS

The use of UDCA in LT patients significantly reduced the SARS-CoV-2 infection rate and showed a dose-dependent protective effect.

Robust Intelligent Monitoring and Measurement System toward Downhole Dynamic Liquid Level

Dynamic liquid level monitoring and measurement in oil wells is essential in ensuring the safe and efficient operation of oil extraction machinery and formulating rational extraction policies that enhance the productivity of oilfields. This paper presents an intelligent infrasound-based measurement method for oil wells' dynamic liquid levels; it is designed to address the challenges of conventional measurement methods, including high costs, low precision, low robustness and inadequate real-time performance. Firstly, a novel noise reduction algorithm is introduced to effectively mitigate both periodic and stochastic noise, thereby significantly improving the accuracy of dynamic liquid level detection. Additionally, leveraging the PyQT framework, a software platform for real-time dynamic liquid level monitoring is engineered, capable of generating liquid level profiles, computing the sound velocity and liquid depth and visualizing the monitoring data. To bolster the data storage and analytical capabilities, the system incorporates an around-the-clock unattended monitoring approach, utilizing Internet of Things (IoT) technology to facilitate the transmission of the collected dynamic liquid level data and computed results to the oilfield's central data repository via LoRa and 4G communication modules. Field trials on dynamic liquid level monitoring and measurement in oil wells demonstrate a measurement range of 600 m to 3000 m, with consistent and reliable results, fulfilling the requirements for oil well dynamic liquid level monitoring and measurement. This innovative system offers a new perspective and methodology for the computation and surveillance of dynamic liquid level depths.

An activatable azophenyl fluorescent probe for hypoxic fluorescence imaging in living cells

Cellular hypoxia is a common pathological process in various diseases. Detecting cellular hypoxia is of great scientific significance for early diagnosis of tumors. The hypoxia fluorescence probe analysis method can efficiently and conveniently evaluate the hypoxia status in tumor cells. These probes are covalently linked by hypoxic recognition groups and organic fluorescent molecules. Currently, the fluorescent molecules used in these probes often exhibit the aggregation-caused quenching effect, which is not conducive to fluorescence imaging in water. Herein, an activatable hypoxia fluorescence probe was constructed by covalently linking aggregation-induced emission luminogens to the hypoxic recognition group azobenzene. It does not emit fluorescence in solution and in solid state under light excitation due to the presence of photosensitive azo bonds. It can be cleaved by intracellular azoreductase into fluorescent amino derivatives with aggregation-induced emission characteristic. As the concentration of oxygen in cells decreases, its fluorescence intensity increases, making it suitable for fluorescence imaging to detect hypoxic environment in live cancer cells. This work broadens the molecular design approach for activatable hypoxia fluorescent probes.

Brassica napus BnaA09.MYB52 enhances seed coat mucilage accumulation and tolerance to osmotic stress during seed germination in Arabidopsis thaliana

Seed coat mucilage plays an important role in promoting seed germination under adversity. Previous studies have shown that Arabidopsis thaliana MYB52 (AtMYB52) can positively regulate seed coat mucilage accumulation. However, the role of Brassica napus MYB52 (BnaMYB52) in accumulation of seed coat mucilage and tolerance to osmotic stress during seed germination remains largely unknown. We cloned the BnaA09.MYB52 coding domain sequence from B. napus cv ZS11, identified its conserved protein domains and elucidated its relationship with homologues from a range of plant species. Transgenic plants overexpressing BnaA09.MYB52 in the A. thaliana myb52-1 mutant were generated through Agrobacterium-mediated transformation and used to assess the possible roles of BnaA09.MYB52 in accumulation of seed coat mucilage and tolerance to osmotic stress during seed germination. Subcellular localization and transcriptional activity assays demonstrated that BnaA09.MYB52 functions as a transcription factor. RT-qPCR results indicate that BnaA09.MYB52 is predominantly expressed in roots and developing seeds of B. napus cv ZS11. Introduction of BnaA09.MYB52 into myb52-1 restored thinner seed coat mucilage in this mutant to levels in the wild type. Consistently, expression levels of three key genes participating in mucilage formation in developing seeds of myb52-1 were also restored to wild type levels by overexpressing BnaA09.MYB52. Furthermore, BnaA09.MYB52 was induced by osmotic stress during seed germination in B. napus, and ectopic expression of BnaA09.MYB52 successfully corrected sensitivity of the myb52-1 mutant to osmotic stress during seed germination. These findings enhance our understanding of the functions of BnaA09.MYB52 and provide a novel strategy for future B. napus breeding.

Design and fabrication of highly thermally conductive 1-1-3 piezoelectric composites

1-3 piezoelectric composites have been widely used in transmitting transducers, medical devices, navigation, aerospace, etc. However, due to poor thermal conduction of inside piezoelectric composites, performance degradation and service life shortening of transmitting transducers are easily caused while working under high-power or continuously operated states. In this paper, a solution is provided by designing and creating highly efficient thermally conductive paths in 1-1-3 piezoelectric composite. This novel design resulted in two-fold increase in heat dissipation rate compared with traditional 1-3 piezoelectric composites, while maintaining high piezoelectric properties. Furthermore, we designed and fabricated an efficient heat dissipation transducer (EHDT) with the novel 1-1-3 piezoelectric composite as the core material, which can relief heat accumulation effectively compared with conventional transducers (CT). The EHDT can achieve three times more power output than the CT at the same temperature threshold of 90 °C.

Coating effect of renatured triple-helix lentinan on the morphology and antimicrobial activity of ZnO synthesized by hydrothermal method

Polysaccharides are considered to be ideal green raw materials for enhancing biocompatibility and dispersion effects of nanoparticles. In this study, we coated and dispersed ZnO nanoparticles (NPs) using the denaturation-renaturation process of a triple helix glucan lentinan (LNT), induced by changes in pH value within the reaction system. Various ZnO/LNT composites with different particle sizes and crystal morphologies were prepared and characterized. The results demonstrated that renatured LNT (r-LNT) effectively encapsulated the {101̄0} crystal planes of ZnO, preventing crystal growth during the renaturation process and resulting in smaller, uniformly dispersed nanoparticles. Among the samples, ZnO/r-LNT-2 exhibited significantly higher antimicrobial activity, and it had a certain inhibitory effect on various plant pathogens. It also displayed the highest inhibitory effect against Candida albicans, with a minimum inhibitory concentration (MIC) of up to 8 μg mL-1. Consistently, ZnO/r-LNT-2 generated the highest amount of reactive oxygen species (ROS), thus exhibiting the most effective antimicrobial activity. However, excessive introduction of the dispersant LNT may reduce these activities. This study provides a foundation for further exploring the detailed mechanism of ROS generation catalyzed by ZnO and for harnessing the full potential of this type of antimicrobial agent.

[Study of proanthocyanidin promotes osteogenic differentiation of human periodontal ligament stem cells through the transcription factor EB-induced autophagy-lysosome pathway]

Objective: To investigate the mechanism of proanthocyanidin (PA) in regulating the osteogenic differentiation of human periodontal ligament stem cells (PDLSCs), and to explore the effects of PA on the expression and nuclear translocation of transcription factor EB (TFEB) and on the autophagy-lysosome pathway. Methods: PDLSCs were divided into control group and PA group, which were subjected to RNA sequencing analysis (RNA Seq) to detect differentially expressed genes. The osteogenic differentiation ability and autophagy level were observed by real-time fluorescence quantitative PCR (RT-qPCR) analysis, alkaline phosphatase (ALP) staining and transmission electron microscope (TEM), respectively. Scratch assay and Transwell assay were used to detect the migration ability of PDLSCs. Lysotracker and immunofluorescence staining were used to detect the biogenesis of lysosomes. The total protein expression of transcription factor EB (TFEB) as well as that in cytoplasm and nucleus were detected by Western blotting. Confocal laser scanning microscope (CLSM) was used to observe the nuclear translocation of TFEB. The PDLSCs were treated with small interfering RNA (siRNA) technology to knock down the expression levels of TFEB gene with or without PA treatment. Western blotting was used to analyze the expressions of autophagy-related proteins Beclin1 and microtubule-associated protein 1 light chain 3 (LC3B), as well as osteogenic-related proteins runt-related transcription factor 2 (RUNX2), ALP, and osteocalcin in PDLSCs. Results: Compared with the control group, the osteogenic-related and autophagy-related genes showed differential expression in PDLSCs after PA treatment (P<0.05). The mRNA expression levels of osteogenic-related genes RUNX2 (2.32±0.15) and collagen type Ⅰ alpha 1 (COL1α1) (1.80±0.18), as well as the autophagy related genes LC3B (1.87±0.08) and Beclin1 (1.63±0.08) were significantly increased in the PA group, compared with the control group (1.01±0.16, 1.00±0.10, 1.00±0.07, 1.00±0.06, respectively, all P<0.01). Compared with the control group, the PA group had higher ALP activity, and more autophagosomes and autophagolysosomes observed by TEM. PA promoted the migration of PDLSCs (P<0.05) and the increased number of lysosomes and the expression of lysosomal associated membrane protein 1 (LAMP1). In the PA group, the relative expression level of total TFEB protein (1.49±0.07) and the nuclear/cytoplasmic expression of TFEB protein (1.52±0.12) were significantly higher than the control group (1.00±0.11, 1.00±0.13, respectively) (t=6.43, P<0.01; t=5.07, P<0.01). The relative nuclear/cytoplasmic fluorescence intensity of TFEB in the PA group (0.79±0.09) was increased compared with the control group (0.11±0.08) (t=8.32, P<0.01). Knocking down TFEB significantly reduced the expression of TFEB (1.00±0.15 vs 0.64±0.04), LAMP1 (1.00±0.10 vs 0.69±0.09), Beclin1 (1.00±0.05 vs 0.60±0.05), and LC3B Ⅱ/Ⅰ (1.00±0.06 vs 0.73±0.07) in PDLSCs (P<0.05, P<0.05, P<0.01, P<0.01). When TFEB gene was knocked down, the expression levels of Beclin1 (1.05±0.11), LC3B Ⅱ/Ⅰ (1.02±0.09), RUNX2 (1.04±0.10), ALP (1.04±0.16), and osteocalcin (1.03±0.15) proteins were significantly decreased in the PA group compared with the pre-knockdown period (1.28±0.03, 1.44±0.11, 1.38±0.11, 1.62±0.11, 1.65±0.17, respectively) (P<0.05, P<0.01, P<0.05, P<0.01, and P<0.01, respectively). Conclusions: PA promotes the osteogenic differentiation of PDLSCs through inducing the expression and nuclear translocation of TFEB and activating the autophagy-lysosome pathway.

Serous surface papillary borderline ovarian tumors: correlation of sonographic features with clinic pathological findings

Serous surface papillary borderline ovarian tumor (SSPBOT) is a distinct subtype of serous borderline ovarian tumor characterized by solid tissue deposition confined to the ovarian surface. Because SSPBOT is rare, there are few published reports on the ultrasonographic features of this condition. In this retrospective study, we investigated 12 cases of SSPBOT. Ultrasound imaging of SSPBOT showed grossly normal ovaries that were encased partially or wholly by tumor deposits that were confined to the surface, with clear demarcation between normal ovarian tissue and surrounding tumors. Color Doppler imaging demonstrated the 'fireworks sign' in all cases of SSPBOT, corresponding to an intratumoral vascular bundle originating from the ovarian vessels and supplying hierarchical branching blood flow to the surrounding tumor. No patient with ovarian high-grade serous carcinoma showed these morphological and Doppler features. In our series, the fireworks sign appeared to be a characteristic feature of SSPBOT that could facilitate correct identification of this tumor. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

[A retrospective study of postoperative adjuvant therapy following immunotherapy combined with targeted therapy and sequential curative surgical procedures for initially unresectable hepatocellular carcinoma]

Objective: To report the clinical efficacy of adjuvant therapy based on pathological results following immunotherapy combined with targeted therapy and sequential curative surgical procedures in patients with initially unresectable hepatocellular carcinoma. Methods: This is a retrospective case series study. Data from 100 patients who underwent adjuvant therapy based on pathological results following immunotherapy combined with targeted therapy and sequential curative surgical procedures with long-term survival were collected from December 2018 to December 2022 at the Faculty of Hepato-Pancreato-Biliary Surgery, First Medical Center, Chinese People's Liberation Army General Hospital. According to inclusion and exclusion criteria, 47 cases were included, among which patients who met the discontinuation criteria and maintained a drug-free tumor-free status. Thirty-nine male and eight female patients were included, with an age of (54.2±18.8)years(range:38 to 73 years) at initial diagnosis. At the time of initial diagnosis, 43 cases (91.5%) were classified as Barcelona Clinic Liver Cancer(BCLC) stage C. Survival curves were made using Kaplan Meier method. Results: Forty-seven patients underwent R0 resection, all achieved a drug-free tumor-free state through postoperative adjuvant therapy based on pathological examination results. Thirty-six patients(76.6%) maintained a drug-free tumor-free survival status for more than 6 months,28 patients(59.6%) for more than 12 months,and 8 patients(17.0%) for more than 24 months. The longest drug-free tumor-free survival in this cohort reached 48 months. The median follow-up time in this study was 32 months. After diagnosis, the overall survival rates at 1- and 3- years were 97.7%(95%CI:93.4% to 100%) and 90.7%(95%CI:82.5% to 99.8%). The postoperative recurrence-free survival rates at 1- and 3- years were 91.0%(95%CI:83.0% to 99.8%) and 71.3%(95%CI:58.7% to 86.5%). Conclusions: The adjuvant therapy based on pathological results following immunotherapy combined with targeted therapy and sequential curative surgical approach provides long-term survival benefits for patients with initially unresectable hepatocellular carcinoma. Standardized adjuvant therapy maybe sustain long-term tumor-free status,and achieve drug-free tumor-free survival.

[Transdermal patches containing Cassia seed extract applied at the navel for slow transit constipation in rats: therapeutic effect and analysis of the spectrum-effect relationship]

OBJECTIVE

To explore the therapeutic effect of transdermal patches containing Cassia seed extract applied at the navel on slow transit constipation (STC) in rats and explore the spectrum-effect relationship of the patches.

METHOD

In a STC rat model established by gavage of compound diphenoxylate suspension for 14 days, the transdermal patches containing low, medium and high doses of Cassia seed extract (41.75, 125.25, and 375.75 mg/kg, respectively) were applied at the Shenque acupoint on the abdomen for 14 days after modeling, with constipation patches (13.33 mg/kg) as the positive control. After the treatment, fecal water content and intestinal propulsion rate of the rats were calculated, the pathological changes in the colon were observed with HE staining. Serum NO and NOS levels and the total protein content and NO, NOS and AChE expressions in the colon tissue were determined. HPLC fingerprints of the transdermal patches were established, and the spectrum-effect relationship between the common peaks of the patches and its therapeutic effect were analyzed.

RESULTS

Treatment with the transdermal patches containing Cassia seed extract significantly increased fecal water content and intestinal propulsion rate of the rat models, where no pathological changes in the colon tissue were detected. The treatment also suppressed the elevations of serum and colonic NO and NOS levels and reduction of AChE in STC rats. Twenty-eight common peaks were confirmed in the HPLC fingerprints of 6 batches of Cassia seed extract-containing patches. Analysis of the spectrum-effect relationship showed that autrantio-obtusin had the greatest contribution to the therapeutic effect of the patches in STC rats.

CONCLUSION

The Cassia seed extract-containing patches alleviates STC in rats via synergistic actions of multiple active ingredients in the extract, where autrantio-obtusin, rhein, chrysoobtusin, obtusin, obtusifolin, emodin, chrysophanol, and physcion are identified as the main active ingredients.

Establishment of a Homologous Silencing System with Intact-Plant Infiltration and Minimized Operation for Studying Gene Function in Herbaceous Peonies

Gene function verification is a crucial step in studying the molecular mechanisms regulating various plant life activities. However, a stable and efficient homologous genetic transgenic system for herbaceous peonies has not been established. In this study, using virus-induced gene silencing technology (VIGS), a highly efficient homologous transient verification system with distinctive advantages was proposed, which not only achieves true "intact-plant" infiltration but also minimizes the operation. One-year-old roots of the representative species, Paeonia lactiflora Pall., were used as the materials; prechilling (4 °C) treatment for 3-5 weeks was applied as a critical precondition for P. lactiflora to acquire a certain chilling accumulation. A dormancy-related gene named HOMEOBOX PROTEIN 31 (PlHB31), believed to negatively regulate bud endodormancy release (BER), was chosen as the target gene in this study. GFP fluorescence was detected in directly infiltrated and newly developed roots and buds; the transgenic plantlets exhibited remarkably earlier budbreak, and PlHB31 was significantly downregulated in silenced plantlets. This study established a homologous transient silencing system featuring intact-plant infiltration and minimized manipulation for gene function research, and also offers technical support and serves as a theoretical basis for gene function discovery in numerous other geophytes.

Inferior Alveolar Nerve Canal Segmentation on CBCT Using U-Net with Frequency Attentions

Accurate inferior alveolar nerve (IAN) canal segmentation has been considered a crucial task in dentistry. Failing to accurately identify the position of the IAN canal may lead to nerve injury during dental procedures. While IAN canals can be detected from dental cone beam computed tomography, they are usually difficult for dentists to precisely identify as the canals are thin, small, and span across many slices. This paper focuses on improving accuracy in segmenting the IAN canals. By integrating our proposed frequency-domain attention mechanism in UNet, the proposed frequency attention UNet (FAUNet) is able to achieve 75.55% and 81.35% in the Dice and surface Dice coefficients, respectively, which are much higher than other competitive methods, by adding only 224 parameters to the classical UNet. Compared to the classical UNet, our proposed FAUNet achieves a 2.39% and 2.82% gain in the Dice coefficient and the surface Dice coefficient, respectively. The potential advantage of developing attention in the frequency domain is also discussed, which revealed that the frequency-domain attention mechanisms can achieve better performance than their spatial-domain counterparts.

[Influence of paraspinal muscle degeneration and postoperative Roussouly classification restoration on mechanical complications in female patients with degenerative scoliosis after surgery]

Objective: To investigate the impact of lumbar paraspinal muscle degeneration and postoperative failure to restore ideal Roussouly classification on the occurrence of mechanical complications (MC) following long-segment spinal correction surgery in female patients with degenerative scoliosis (DS). Methods: The clinical data of 72 female DS patients who underwent long-segment spinal correction surgery in Gulou Hospital from June 2017 to November 2021 were retrospectively analyzed. According to whether restoring the ideal Roussouly classification after surgery, the patients were divided into R group(recovery group) (n=51) and N group(non-recovery group) (n=21). According to whether mechanical complications occurred after operation within two years, the patients were divided into MC (mechanical complications)group (n=24) and NMC(non-mechanical complications) group (n=48). The RM group (n=14) experienced mechanical complications in the R group, while the RN group (n=37) did not. The NM group (n=10) experienced mechanical complications in the N group, while the NN group (n=11) did not.Radiographic assessment included Sagittal parameters of spine and pelvis, standardized cross-sectional area (SCSA) and fat infiltration rate (FI%) of paraspinal muscle at each lumbar disc level. Results: The age of DS patients in this study was (61.4±6.2) years.The incidence of MC was 33.33%(n=24)in all patients. The incidence of MC was 27.45%(n=14)in group R and 47.62%(n=10) in group N. The correction amount of pelvic tilt angle (PT) (-11.62°±10.06° vs -7.04°±8.45°, P=0.046) and T1 pelvic angle(TPA)(-12.88°±11.23° vs -7.31°±9.55°, P=0.031)during surgery were significantly higher in MC group compared to the NMC group. In group R, the FI% of paraspinal muscles in each lumbar segment of patients with postoperative MC was higher than that in patients without MC (P<0.05). In the R and N groups, there was no significant difference inthe SCSA of the lumbar paravertebral muscles between patients with postoperative MC and those without MC at each level (all P>0.05). Multivariate logistic regression analysis showed that the average FI% of lumbar PSM was correlated with the occurrence of MC after spinal fusion in DS patients.The average FI% of lumbar PSM≥22.63% was a risk factors for MC after spinal fusion (P=0.010,OR=1.088, 95%CI:1.020-1.160). Conclusions: Female DS patients with higher degree of preoperative paraspinal muscle degeneration have a higher incidence of postoperative mechanical complications. For these patients,.there is still a higher risk of mechanical complications after surgery even if the ideal Roussouly classification is restored after surgery.

Impaired local Vitamin D3 metabolism contributes to IL-36g overproduction in epithelial cells in chronic rhinosinusitis with nasal polyps

BACKGROUND

Vitamin D (VD) possesses immunomodulatory properties, but its role in chronic rhinosinusitis with nasal polyps (CRSwNP) remains poorly studied. Herein, we aim to explore the regulation and function of VD3 in CRSwNP.

METHODS

25-hydroxyvitamin D3 (25VD3) levels in serum and tissue lysates were detected by ELISA. The expression of VD receptor (VDR) and cytochrome P450 family 27 subfamily B member 1 (CYP27B1), the enzyme that converts 25VD3 to the active 1,25-hydroxyvitamin D3 (1,25VD3), and their expression regulation in human nasal epithelial cells (HNECs) were studied by RT-PCR, western blotting, immunofluorescence, and flow cytometry. RNA sequencing was performed to identify genes regulated by 1,25VD3 in HNECs. HNECs and polyp tissue explants were treated with 1,25VD3, 25VD3, and dexamethasone.

RESULTS

25VD3 levels in serum and nasal tissue lysates were decreased in patients with eosinophilic and noneosinophilic CRSwNP than control subjects. The expression of VDR and CYP27B1 were reduced in eosinophilic and noneosinophilic CRSwNP, particularly in nasal epithelial cells. VDR and CYP27B1 expression in HNECs were downregulated by interferon y and poly (I:C). Polyp-derived epithelial cells demonstrated an impaired ability to convert 25VD3 to 1,25VD3 than control tissues. 1,25VD3 and 25VD3 suppressed IL-36y production in HNECs and polyp tissues, and the effect of 25VD3 was abolished by siCYP27B1 treatment. Tissue 25VD3 levels negatively correlated with IL-36y expression and neutrophilic inflammation in CRSwNP.

CONCLUSION

Reduced systemic 25VD3 level, local 1,25VD3 generation and VDR expression result in impaired VD3 signaling activation in nasal epithelial cells, thereby exaggerating IL-36y production and neutrophilic inflammation in CRSwNP.

Comparison of Omicron breakthrough infection versus monovalent SARS-CoV-2 intramuscular booster reveals differences in mucosal and systemic humoral immunity

Our understanding of the quality of cellular and humoral immunity conferred by COVID-19 vaccination alone versus vaccination plus SARS-CoV-2 breakthrough (BT) infection remains incomplete. While the current (2023) SARS-CoV-2 immune landscape of Canadians is complex, in late 2021 most Canadians had either just received a third dose of COVID-19 vaccine, or had received their two-dose primary series and then experienced an Omicron BT. Herein we took advantage of this coincident timing to contrast cellular and humoral immunity conferred by three doses of vaccine versus two doses plus BT. Our results show thatBT infection induces cell-mediated immune responses to variants comparable to an intramuscular vaccine booster dose. In contrast, BT subjects had higher salivary immunoglobulin (Ig)G and IgA levels against the Omicron spike and enhanced reactivity to the ancestral spike for the IgA isotype, which also reacted with SARS-CoV-1. Serumneutralizing antibody levels against the ancestral strain and the variants were also higher after BT infection. Our results support the need for the development of intranasal vaccines that could emulate the enhanced mucosal and humoral immunity induced by Omicron BT without exposing individuals to the risks associated with SARS-CoV-2 infection.

Construct validation of machine learning for accurately predicting the risk of postoperative surgical site infection following spine surgery

BACKGROUND

This study aimed to evaluate the risk factors for machine learning (ML) algorithms in predicting postoperative surgical site infection (SSI) following spine surgery.

METHODS

This prospective cohort study included 986 patients who underwent spine surgery at Taizhou People's Hospital Affiliated to Nanjing Medical University from January 2015 to October 2022. Supervised ML algorithms included support vector machine, logistic regression, random forest, XGboost, decision tree, k-nearest neighbour, and naïve Bayes (NB), which were tested and trained to develop a predicting model. The ML model performance was evaluated from the test dataset. We gradually analysed their accuracy, sensitivity, and specificity, as well as the positive predictive value, negative predictive value, and area under the curve.

RESULTS

The rate of SSI was 9.33%. Using a backward stepwise approach, we identified that the remarkable risk factors predicting SSI in the multi-variate Cox regression analysis were age, body mass index, smoking, cerebrospinal fluid leakage, drain duration and pre-operative albumin level. Compared with other ML algorithms, the NB model had the highest performance in seven ML models, with an average area under the curve of 0.95, sensitivity of 0.78, specificity of 0.88, and accuracy of 0.87.

CONCLUSIONS

The NB model in the ML algorithm had excellent calibration and accurately predicted the risk of SSI compared with the existing models, and might serve as an important tool for the early detection and treatment of SSI following spinal infection.

Dental Pulp Stem Cell-Derived Exosomes Promote Sciatic Nerve Regeneration via Optimizing Schwann Cell Function

Repair strategies for injured peripheral nerve have achieved great progresses in recent years. However, the clinical outcomes remain unsatisfactory. Recent studies have found that exosomes secreted by dental pulp stem cells (DPSC-exos) have great potential for applications in nerve repair. In this study, we evaluated the effects of human DPSC-exos on improving peripheral nerve regeneration. Initially, we established a coculture system between DPSCs and Schwann cells (SCs) in vitro to assess the effect of DPSC-exos on the activity of embryonic dorsal root ganglion neurons (DRGs) growth in SCs. We extracted and labeled human DPSC-exos, which were subsequently utilized in uptake experiments in DRGs and SCs. Subsequently, we established a rat sciatic nerve injury model to evaluate the therapeutic potential of DPSC-exos in repairing sciatic nerve damage. Our findings revealed that DPSC-exos significantly promoted neurite elongation by enhancing the proliferation, migration, and secretion of neurotrophic factors by SCs. In vivo, DPSC-exos administration significantly improved the walking behavior, axon regeneration, and myelination in rats with sciatic nerve injuries. Our study underscores the vast potential of DPSC-exos as a therapeutic tool for tissue-engineered nerve construction.

Deciphering the developmental trajectory of tissue-resident Foxp3+ regulatory T cells

Foxp3+ TREG cells have been at the focus of intense investigation for their recognized roles in preventing autoimmunity, facilitating tissue recuperation following injury, and orchestrating a tolerance to innocuous non-self-antigens. To perform these critical tasks, TREG cells undergo deep epigenetic, transcriptional, and post-transcriptional changes that allow them to adapt to conditions found in tissues both at steady-state and during inflammation. The path leading TREG cells to express these tissue-specialized phenotypes begins during thymic development, and is further driven by epigenetic and transcriptional modifications following TCR engagement and polarizing signals in the periphery. However, this process is highly regulated and requires TREG cells to adopt strategies to avoid losing their regulatory program altogether. Here, we review the origins of tissue-resident TREG cells, from their thymic and peripheral development to the transcriptional regulators involved in their tissue residency program. In addition, we discuss the distinct signalling pathways that engage the inflammatory adaptation of tissue-resident TREG cells, and how they relate to their ability to recognize tissue and pathogen-derived danger signals.