Characterisation of the mitochondrial genome and phylogenetic analysis of Toxocara apodemi (Nematoda: Ascarididae)

We first sequenced and characterised the complete mitochondrial genome of Toxocara apodeme, then studied the evolutionary relationship of the species within Toxocaridae. The complete mitochondrial genome was amplified using PCR with 14 specific primers. The mitogenome length was 14303 bp in size, including 12 PCGs (encoding 3,423 amino acids), 22 tRNAs, 2 rRNAs, and 2 NCRs, with 68.38% A+T contents. The mt genomes of T. apodemi had relatively compact structures with 11 intergenic spacers and 5 overlaps. Comparative analyses of the nucleotide sequences of complete mt genomes showed that T. apodemi had higher identities with T. canis than other congeners. A sliding window analysis of 12 PCGs among 5 Toxocara species indicated that nad4 had the highest sequence divergence, and cox1 was the least variable gene. Relative synonymous codon usage showed that UUG, ACU, CCU, CGU, and UCU most frequently occurred in the complete genomes of T. apodemi. The Ka/Ks ratio showed that all Toxocara mt genes were subject to purification selection. The largest genetic distance between T. apodemi and the other 4 congeneric species was found in nad2, and the smallest was found in cox2. Phylogenetic analyses based on the concatenated amino acid sequences of 12 PCGs demonstrated that T. apodemi formed a distinct branch and was always a sister taxon to other congeneric species. The present study determined the complete mt genome sequences of T. apodemi, which provide novel genetic markers for further studies of the taxonomy, population genetics, and systematics of the Toxocaridae nematodes.

Constructing Robust 3D Ionomer Networks in the Catalyst Layer to Achieve Stable Water Electrolysis for Green Hydrogen Production

The widespread application of proton exchange membrane water electrolyzers (PEMWEs) is hampered by insufficient lifetime caused by degradation of the anode catalyst layer (ACL). Here, an important degradation mechanism has been identified, attributed to poor mechanical stability causing the mass transfer channels to be blocked by ionomers under operating conditions. By using liquid-phase atomic force microscopy, we directly observed that the ionomers were randomly distributed (RD) in the ACL, which occupied the mass transfer channels due to swelling, creeping, and migration properties. Interestingly, we found that alternating treatments of the ACL in different water/temperature environments resulted in forming three-dimensional ionomer networks (3D INs) in the ACL, which increased the mechanical strength of microstructures by 3 times. Benefitting from the efficient and stable mass transfer channels, the lifetime was improved by 19 times. A low degradation rate of approximately 3.0 μV/h at 80 °C and a high current density of 2.0 A/cm2 was achieved on a 50 cm2 electrolyzer. These data demonstrated a forecasted lifetime of 80 000 h, approaching the 2026 DOE lifetime target. This work emphasizes the importance of the mechanical stability of the ACL and offers a general strategy for designing and developing a durable PEMWE.

[The influencing factors on the spinal sagittal alignment and global balance status of degenerative thoracolumbar kyphosis]

Objective: To explore the effect of degenerative thoracolumbar kyphosis (DTLK) on the sagittal alignment of the spine, as well as the impact on spinal parameters and imbalance secondary to thoracolumbar kyphosis. Methods: A case-control study. A total of 128 DTLK patients who aged over 50 years [thoracolumbar kyphosis (TLK)>15°] treated in Peking University People's Hospital from January 2018 to December 2021 (DTLK group) were retrospectively included in this study. Other 73 contemporaneous patients with lumbar spinal stenosis or disc herniation without thoracolumbar kyphosis (TLK=0°±15°) were enrolled into the control group. The following parameters were obtained on spine X-ray: TLK, thoracic kyphosis (TK), lumbar lordosis (LL) and sagittal vertical axis (SVA). In addition, the osteoporosis (OP) was evaluated by dual-emission X-ray absorptiometry (DXA), and the L5/S1 disc signal grading (Pfirrmann grading) was evaluated on MRI. Based on the age, the Lafage formula SVA=2× (age-55)+25 was used to distinguish balance/imbalance, and the DTLK patients were divided into balanced and an imbalanced group, the characteristics and influencing factors of the loss of sagittal balance in this population were clarified, and the interaction among various parts of the spine under a state of balance was analyzed too. Results: The TK (30.0°±13.5° vs 24.2°±7.4°) and TLK (26.6°±9.7° vs 6.0°±6.6°) in the DTLK group were both larger than those in control group while LL was smaller (34.4°±17.7° vs 44.2°±10.3°) (all P<0.001). TK was correlated to TLK (r=0.234, P=0.008) and LL (r=0.539, P<0.001) in DTLK group. LL loss was positively correlated to L5/S1 disc signal reduction (r=0.253, P=0.044). LL loss [RR=1.04(1.01-1.08)] and OP [RR=3.97(1.09, 14.50)] were influencing factors for the occurrence of imbalance in DTLK patients. The influencing factors for TK in DTLK balance group were LL (β=0.572, P<0.001) and age (β=0.351, P=0.045). The positive influencing factor for TK in imbalanced group is LL (β=0.209, P=0.015), and the impact is weaker than balanced group. Conclusions: Loss of LL and osteoporosis are more likely to cause imbalance and kyphosis in DTLK patients. In DTLK balance group, the proximal spine is regulated by lumbar spine, and the synergistic effect between the two parts maintains balance.

A high resolution reaction microscope with universal two-region time-focusing method

This paper presents a novel reaction microscope designed for ion-atom collision investigations, established at the Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China. Its time-of-flight (TOF) spectrometer employs an innovative flight-time focusing method consisting of two acceleration regions, providing optimal time focusing conditions for charged fragments with diverse initial velocities. The TOF spectrometer's axis intentionally tilts by 12° relative to the ion beam direction, preventing potential obstructions from the TOF grid electrodes. The introduced focusing method allows for a flexible time-focusing TOF spectrometer design without restricting the length ratio of the two regions. In addition, this configuration in our case significantly suppresses noise on the recoil ion detector produced by residual gas in the ion beam trajectory, which is a considerable challenge in longitudinal spectrometers. In a test experiment on the single electron capture reaction involving 62.5 keV/u He2+ ions and a helium atomic beam, the recoil longitudinal momentum resolution achieved 0.068 atomic units. This novel configuration and successful test run show excellent precision for ion-atom collision studies.

Preparation and characterization of pickering emulsion stabilized by lovastatin nanoparticles for vaccine adjuvants

While research on mevalonate inhibitors as vaccine adjuvants has made great progress to enhance the effectiveness of the vaccine, co delivery of lovastatin and antigens (OVA) remains an enormous challenge. Here, we encapsulated lovastatin into PLGA nanoparticles. PLGA loading lovastatin was further emulsified with squalene to prepare Pickering emulsion. The emulsification conditions of Pickering emulsion were optimized, and the optimal preparation conditions were obtained. After loading lovastatin and OVA, the size and zeta potential of LS-PPAS/OVA was 1043.33 nm and -22.07 mv, the adsorption rate of OVA was 63.34 %. The adsorbing of LS-PLGA nanoparticles on the surface of squalene in Pickering emulsions was demonstrated by Fluorescent confocal microscopy. After immunization, LS-PPAS enhanced the activation of dendritic cells in lymph nodes, further study found LS-PPAS not only elicited elevated levels of OVA-specific IgG and its subtypes, but also promoted the secretion of TNF-α, IFN-γ, and IL-6 in serum as a marker of cellular immunity. Importantly, LS-PPAS showed sufficient security through monitoring levels of biochemical parameters in serum and pathological observation of organ following vaccinations. LS-PPAS may act as a promising vaccine carrier to produce strong humoral and cellular immunity with acceptable safety.

Neuroprotective effects of Rehmannia glutinosa polysaccharide on chronic constant light (CCL)-induced oxidative stress and autophagic cell death via the AKT/mTOR pathway in mouse hippocampus and HT-22 cells

Rehmannia glutinosa polysaccharide (RGP) has been reported to exhibit anti-anxiety effects, yet the underlying mechanism remains unclear. Chronic constant light (CCL) induced cognitive dysfunction associated with oxidative stress in mice has been reported. Here, the neuroprotective effect of RGP on hippocampal neuron damage in CCL-treated mice was investigated. In vivo study, mice were subjected to CCL for 4 weeks and/or oral administration of 100, 200 and 400 mg/kg RGP every other day. In vitro experiment, hippocampal neuron cells (HT-22) was exposed to LED light and/or supplemented with 62.5, 125 and 250 μg/mL RGP. Mice exposed to CCL showed impaired cognitive and depressive-like behavior in the hippocampus, which were reversed by RGP. Meanwhile, RGP reversed light-induced oxidative stress and autophagy both in mice and hippocampal neuron cells (HT-22). Furthermore, compared with Light-exposed group, RGP treatment activated the AKT/mTOR pathway. Importantly, the AKT inhibitor Perifosine significantly weakened the neuroprotective of RGP on Light-induced oxidative stress and autophagy in HT-22 cells by inhibiting AKT/mTOR pathway and increasing the content of autophagy-related protein. Our data demonstrated, for the first time, that oxidative stress and the AKT/mTOR pathway plays a critical role in Light-induced apoptosis and autophagic cell death in mice and HT-22 cells.

A silver-mediated radical process of β-keto sulfones for the synthesis of 2,3-diacyl furans

A facile and efficient method for constructing 2,3-diacyl trisubstituted furans via a silver-mediated radical process of β-keto sulfones is developed. The reaction mechanism has been carefully investigated, revealing that the transformation proceeds through a radical pathway, leading to moderate to good yields of desired products.

Adaptive convolutional sparsity with sub-band correlation in the NSCT domain for MRI image fusion

Objective.Multimodal medical image fusion (MMIF) technologies merges diverse medical images with rich information, boosting diagnostic efficiency and accuracy. Due to global optimization and single-valued nature, convolutional sparse representation (CSR) outshines the standard sparse representation (SR) in significance. By addressing the challenges of sensitivity to highly redundant dictionaries and robustness to misregistration, an adaptive convolutional sparsity scheme with measurement of thesub-band correlationin the non-subsampled contourlet transform (NSCT) domain is proposed for MMIF.Approach.The fusion scheme incorporates four main components: image decomposition into two scales, fusion of detail layers, fusion of base layers, and reconstruction of the two scales. We solved a Tikhonov regularization optimization problem with source images to obtain the base and detail layers. Then, after CSR processing, detail layers were sparsely decomposed using pre-trained dictionary filters for initial coefficient maps. NSCT domain'ssub-band correlationwas used to refine fusion coefficient maps, and sparse reconstruction produced the fused detail layer. Meanwhile, base layers were fused using averaging. The final fused image was obtained via two-scale reconstruction.Main results.Experimental validation of clinical image sets revealed that the proposed fusion scheme can not only effectively eliminate the interference of partial misregistration, but also outperform the representative state-of-the-art fusion schemes in the preservation of structural and textural details according to subjective visual evaluations and objective quality evaluations.Significance. The proposed fusion scheme is competitive due to its low-redundancy dictionary, robustness to misregistration, and better fusion performance. This is achieved by training the dictionary with minimal samples through CSR to adaptively preserve overcompleteness for detail layers, and constructing fusion activity level withsub-band correlationin the NSCT domain to maintain CSR attributes. Additionally, ordering the NSCT for reverse sparse representation further enhancessub-band correlationto promote the preservation of structural and textural details.

Treatment with glatiramer acetate in APPswe/PS1dE9 mice at an early stage of Alzheimer's disease prior to amyloid-beta deposition delays the disease's pathological development and ameliorates cognitive decline

Background

Alzheimer's disease (AD) is characterized by neuroinflammation, which is frequently accompanied by immune system dysfunction. Although the mechanism of neurodegenerative lesions is unclear, various clinical trials have highlighted that early intervention in AD is crucial to the success of treatment. In order to explore the potential of immunotherapy in the early period of AD, the present study evaluated whether application of glatiramer acetate (GA), an immunomodulatory agent approved for remitting-relapsing multiple sclerosis (RRMS), in the early stages of AD prior to amyloid beta (Aβ) deposition altered the Aβ pathology and cognitive impairments in APPswe/PSEN1dE9 (APP/PS1) transgenic mice.

Methods

We treated two cohorts of pre-depositing and amyloid-depositing (2- and 6-month-old) APP/PS1 mice with weekly-GA subcutaneous injection over a 12-week period. We then tested spatial learning and memory using the Morris water maze (MWM) and the Y maze. Immunohistochemistry staining was utilized to analyze Aβ burden in the brain as well as activated microglia. Furthermore, the inflammatory cytokine milieu within brains was estimated by quantitative real-time polymerase chain reaction, and the peripheral CD4+CD25+Foxp3+ regulatory T cells (Tregs) in the spleen were measured by flow cytometry.

Results

We found that early GA administration reduced Aβ burden and ameliorated cognitive decline. Meanwhile, the immune microenvironment had changed in the brain, with an increase in the production of anti-inflammatory cytokines and a decrease in microglial activation. Interestingly, early GA administration also modulated the peripheral immune system through the amplification of Tregs in the spleen.

Conclusion

Overall, our findings revealed that GA treatment might enhance the central and peripheral immune systems' protective capabilities in the early stages of AD, eventually improving cognitive deficits. Our research supports the advantages of immunomodulatory treatments for AD at an early stage.

Association of cord plasma metabolites with birth weight: results from metabolomic and lipidomic studies of discovery and validation cohorts

BACKGROUND

Birth weight is a good predictor of fetal intrauterine growth and long-term health. Although several studies have evaluated the relationship between metabolites and birth weight, no prior study has comprehensively investigated the metabolomic and lipidomic and further validated and quantified meaningful metabolites.

METHODS

Firstly, a pseudotargeted metabolomics approach was applied to detect 2418 metabolites in 504 cord blood samples in the discovery set enrolled from the Wuhan Healthy Baby Cohort (HBC), China. Metabolome-wide association scan (MWAS) analysis and pathway enrichment were applied to discover metabolites and metabolic pathways that were significantly associated with birth weight for gestational age (BWGA) z-score. Logistic regression models were used to analyze the association of metabolites in the most significantly associated pathways with small for gestational age (SGA) and low birth weight (LBW). Subsequently, 350 cord blood samples in a validation cohort were subjected to targeted analysis to validate the metabolites screened from the discovery cohort.

RESULTS

In the discovery set, 513 metabolites were significantly associated with BWGA z-score (PFDR <0.05), of which 298 KEGG-annotated metabolites were included in the pathway analysis. The primary bile acid biosynthesis pathway was the most relevant metabolic pathway associated with BWGA z-score in our study. Elevated cord plasma primary bile acids were associated with lower BWGA z-score and higher odds of SGA or LBW in the discovery and validation cohorts. In the validation set, a 2-fold increase in taurochenodeoxycholic acid (TCDCA) and taurocholic acid (TCA) was associated with 0.10 (95% CI: 0.00, 0.20) and 0.18 (95 %CI: 0.04, 0.31) decrease in BWGA z-score, respectively, after adjusting for covariates. In addition, a 2-fold increase in cord plasma TCDCA and TCA was associated with an adjusted odds ratio of 1.52 (1.00, 2.30) and 1.77 (1.05, 2.98) for SGA, respectively. The adjusted ORs for a 2-fold increase in TCDCA and TCA concentrations were 2.39 (95% CI 1.00, 5.71) and 3.21 (0.96, 10.74) for LBW, respectively.

CONCLUSIONS

The results indicate a significant association between primary bile acids and lower BWGA z-score, as well as higher risk of SGA and LBW. Abnormalities of primary bile acid metabolism may play an important role in restricted fetal development. This article is protected by copyright. All rights reserved.

Molecular Ionization Dissociation Induced by Interatomic Coulombic Decay in an ArCH_{4}-Electron Collision System

Interatomic Coulombic decay (ICD) is a significant fragmentation mechanism observed in weakly bound systems. It has been widely accepted that ICD-induced molecular fragmentation occurs through a two-step process, involving ICD as the first step and dissociative-electron attachment (DEA) as the second step. In this study, we conducted a fragmentation experiment of ArCH_{4} by electron impact, utilizing the coincident detection of one electron and two ions. In addition to the well-known decay pathway that induces pure ionization of CH_{4}, we observed a new channel where ICD triggers the ionization dissociation of CH_{4}, resulting in the cleavage of the C-H bond and the formation of the CH_{3}^{+} and H ion pair. The high efficiency of this channel, as indicated by the relative yield of the Ar^{+}/CH_{3}^{+} ion pair, agrees with the theoretical prediction [L. S. Cederbaum, J. Phys. Chem. Lett. 11, 8964 (2020).JPCLCD1948-718510.1021/acs.jpclett.0c02259; Y. C. Chiang et al., Phys. Rev. A 100, 052701 (2019).PLRAAN2469-992610.1103/PhysRevA.100.052701]. These results suggest that ICD can directly break covalent bonds with high efficiency, bypassing the need for DEA. This finding introduces a novel approach to enhance the fragmentation efficiency of molecules containing covalent bonds, such as DNA backbone.

Polysaccharide from walnut green husk alleviates liver inflammation and gluconeogenesis dysfunction by altering gut microbiota in ochratoxin A-induced mice

Walnut green husk polysaccharides (WGP) are isolated from the walnut green husk with a mean molecular weight of 12.77 kDa. The structural characterization revealed by methylation and NMR analysis indicated that WGP might consist of →4-α-D-Galp-(1→, α-D-Galp (1→, and →2)-α-L-Rhap-(1→. Previous studies have been demonstrated that WGP effectively prevented liver injury and modulated gut microbiota in high fructose-treated mice and high fat diet-treated rats. In this study, we found for the first time that WGP presenting outstanding protective effects on liver inflammation and gluconeogenesis dysfunction induced by ochratoxin A (OTA) in mice. Firstly, WGP decreased oxidative stress, down-regulated the expression of inflammatory factors and inhibited the TLR4/p65/IκBα pathway in the liver. Then, WGP reversed OTA-induced lower phosphoenolpyruvate carboxyl kinase (PEPCK), and glucose 6-phosphatase (G6PC) activities in the liver. Furthermore, WGP increased the diversity of gut microbiota and the abundance of beneficial bacteria, especially Lactobacillus and Akkermansia. Importantly, the results of fecal microbiota transplantation (FMT) experiment further confirmed that gut microbiota involved in the protective effects of WGP on liver damage induced by OTA. Our results indicated that the protective effect of WGP on liver inflammation and gluconeogenesis dysfunction caused by OTA may be due to the regulation of gut microbiota.

Evaluation of Treatment Interruptions and Recovery during Biology-Guided Radiotherapy Delivery

PURPOSE/OBJECTIVE(S)

A Biology-guided Radiotherapy (BgRT) based device is designed to use Positron Emission Tomography (PET) signals to achieve tracked dose delivery. The goal of this study is to investigate the dose delivery accuracy in case of interruption during BgRT treatment, and resumption in a separate treatment session for a multi-target delivery, as the PET activity continues to decay.

MATERIALS/METHODS

A custom-built large anthropomorphic phantom (LAP) including a 26 mm spherical target with 3D independent motion and two 22 mm spherical targets with 1D sinusoidal motion embedded in water was used. All three targets were filled with FGD in an 8:1 target to background uptake ratio (41.52 kBq/ml in target and 5.19 kBq/ml in background). During BgRT delivery, the treatment was intentionally paused during delivery to the second target and the current treatment session was ended to generate a partial fraction. Then the partial fraction was continued in a new session, where the CT scan localization and PET pre-scan were repeated using the existing PET activity present in the phantom. The newly acquired PET pre-scan, was then used to determine if sufficient PET counts were present to resume treatment delivery. The interruption and recovery algorithm is designed to calculate the fluence that needs to be delivered to the remaining targets as well as the residual fluence to be given to the targets that have already received partial dose prior to the interruption. Once the new fluence is recomputed, the treatment is resumed. The delivered doses were captured using radiochromic film (EBT-XD) inserted in the target as well as post-treatment dose calculations based on the delivered beamlet sequence to evaluate the results in terms of dosimetric coverage and margin loss. The margin loss is calculated as the maximum difference between the distance from the Clinical Target Volume (CTV) contour to the 97% isodose contour in the treatment plan and the on the film. The dosimetric coverage is defined as the percentage of voxels within the CTV that lies within 97% and 130% of the prescribed dose.

RESULTS

As shown in the table below, a margin loss of less than 3 mm for all targets and 100% CTV coverage was achieved. After treatment interruptions, the PET safety evaluation based on the PET pre-scan helped to determine whether the treatment could be continued on the same day using the same injected PET activity (an NTS value ≧ 2 and AC value ≧ 5 kBq/ml).

CONCLUSION

This study demonstrated that the BgRT system is able to deliver the prescribed dose to all targets with independent motion, even when an interruption and resumption occurs during treatment. In case such an interruption if the remaining PET activity satisfies the BgRT safety evaluation, the treatment can continue to deliver the remainder of the BgRT doses.

Intrafraction Dosimetric Evaluation of Biology-Guided Radiotherapy to a Target Under Respiratory Motion

PURPOSE/OBJECTIVE(S)

To evaluate the reproducibility and variability of biology-guided radiotherapy (BgRT) treatments using a large anthropomorphic phantom modeling the motion amplitude of a lung tumor.

MATERIALS/METHODS

RefleXion X1 is equipped with two opposing 90 degrees PET detector arcs to capture the radionuclide emissions and direct the 6MV Linac to treat the lesions in real time. A custom-built phantom filled with a liquid [¹⁸F]Fluorodeoxyglucose (FDG) solution was used. Fillable target and OAR structures were 3D printed and attached to motion stages. The GTV = CTV was matched to the spherical 22 mm diameter target, and the PTV was a 5 mm expansion from the CTV volume. The Biology Tracking Zone (BTZ) was generated after adding 5 mm margin to the motion extent of the CTV. The OAR was a large C-shape annulus (emulating a heart) that was approximately 3 cm from the target. The 3D independent motion trajectory of the target was designed to mimic lung motion: range of +5.8 mm to -4.9 mm in LR, range of +14.4 mm to -11.3 mm in SI, and range of +5.2 mm to -5.1 mm in AP directions. The OAR motion waveform used a 1D sinusoidal pattern with a 5 mm amplitude in SI direction. The target and the OAR were filled with 40 kBq/mL while the background had 5 kBq/mL FDG. A BgRT Modeling (imaging-only) PET acquisition was performed using RefleXion X1 and used to generate a 4-fraction BgRT treatment plan prescribing 10 Gy/fraction to PTV. For each delivery, target, OAR and background were filled with the same FDG concentrations as in the BgRT Modeling PET planning scan. Dosimetry to the target and OAR were both measured using an ion-chamber (Exradin A14SL) and film in the coronal plane through the center of the GTV for all 4 fractions.

RESULTS

The mean activity concentration within the (BTZ) was 7.4 ± 0.8 kBq/mL. The calculated signal-to-noise ratio metric (Normalized Target Signal) within the BTZ was 4.0 ± 0.3. Total treatment times were all less than 35 minutes (34.3 ± 0.2). Prescription dose coverage to the CTV for all 4 fractions was 100%. Ion chamber measurements in the CTV were -1.6 ± 1.3% relative to the planned dose over the active area of the ion-chamber. Minimum and maximum doses to the CTV, measured on film, were -7.7 ± 2.2% and 1.3 ± 1.4%, calculated relative to the planned dose distribution, respectively. The OAR maximum point dose measured on film was -8.7 ± 2.9%, calculated relative to the maximum OAR dose predicted on the bounded dose-volume histogram.

CONCLUSION

Based on this initial study, accurate and reproducible dosimetry can be achieved for targets under respiratory motion using biology-guided radiotherapy over the course of a complete course of treatment. Further studies are needed to evaluate the intrafraction dosimetry of BgRT delivery under various motion models and tumor sizes.

Dosimetric Accuracy of Multi-Target Biology-Guided Radiotherapy Treatments in a Single Session

PURPOSE/OBJECTIVE(S)

We present the first dosimetric measurements of single session, multi-target BgRT deliveries using a clinically realistic motion phantom on a research-only version of the RefleXion X1 system.

MATERIALS/METHODS

A custom-made anthropomorphic phantom of a human torso with embedded fillable targets mimicking 18F-FDG-avid lesions was used. From the three embedded spherical targets, Target 1 was 26 mm in diameter coupled with a 3D independent respiratory motion with 22 mm range, whereas Target 2 and 3 were 22 mm in diameter and moved with a 1D 5 mm maximum sinusoidal motion. The 18F-FDG concentration in the background cavity of the phantom was 5 kBq/ml, and the targets were loaded with 10:1, 8:1 and 6:1 contrast relative to the background for Targets 1, 2, 3, respectively. Spherical structures were contoured as GTVs (CTV = GTV) and a 5 mm margin was added to create PTVs. Motion extent of the tumors were captured to create biological tracking zones for each target. Treatment plans were generated using a research version of the Reflexion treatment planning software to deliver 8 Gy/fx to the PTVs. The treatment delivery was repeated 2 times, and each time the phantom was refilled according to the plan. PET image evaluation metrics for each of the three targets were also recorded. Target dosimetry was measured using a combination of radiographic film and ion chamber. The maximum distance between the 97% prescription isodose line from the plan and the film measurements was used to characterize the dosimetric accuracy of the tracked deliveries. CTV and PTV min, max, and mean doses measured on film were also recorded for each target.

RESULTS

Treatment plans were successfully created with 100% prescription dose coverage to each target loaded with different FDG ratios. Total treatment times for the single-plan, three-target deliveries were less than 80 minutes. PET evaluation metrics at imaging-only and pre-scan, and planning and film dosimetry to the GTV and PTV for each of the three targets is shown in table below (mean ± standard deviation of both deliveries). The CTV dose coverage was maintained for all targets. The shrinkage distance of the 97% prescription dose isodose line on the film plane for all three targets was less than 3 mm for both tests, and ranged from -0.4 to -2.34 mm.

CONCLUSION

These results demonstrate that high tracking accuracy and dosimetric accuracy can be achieved in single session, multi-target deliveries over a range of target-to-background 18F-FDG concentrations and target motion patterns.

Treatment Plan Creation and Delivery with and without BgRT for Static and Motion Trajectories

PURPOSE/OBJECTIVE(S)

In this work we try to validate the motion tracking capabilities of BgRT for periodic and step motion trajectories. SBRT plans that matches the corresponding BgRT plans are created and delivered to the same phantom with and without motion and results are evaluated. Using BgRT based SBRT plans eliminates any user bias and creates SBRT plans that would represent treatment delivery scenarios that could have happened if the PET guided BgRT was not present for that treatment.

MATERIALS/METHODS

To validate SBRT plans that matches the BgRT plans, we used three different types of motion patterns (1) static, (2) lung tumor motion and (3) one-centimeter step-shift. The lung tumor motion (∼25 mm in IEC-Y, ∼7 mm in IEC-X and ∼ 10 mm in IEC-Z) was used as it represents a continuous motion of the target for the entire length of the study while the step-shift case corresponds to the patient or tumor shifting between the localization CT and the start of treatment. First, a 10 Gy per fraction BgRT plan was created for each of the three experiments based on the corresponding PET image. Then, the BgRT plans were delivered to the corresponding targets with and without motion and results are evaluated. To perform a comparative study that assess the performance of BgRT and traditional SBRT (planning and delivery methods), the exact same plan fluence of BgRT plan for each experiment was used to create the corresponding SBRT plans. The newly created SBRT plans were delivered to the corresponding phantom experiments and were compared against BgRT delivery in terms of dose coverage and target margin loss using radiochromic film that moves with the target. The margin loss was calculated as the difference between the distance from the CTV contour to the 97% isodose contour in the treatment plan and the CTV contour to the 97% isodose contour on the film. Dosimetric coverage was on the other hand calculated as the percentage of the voxels within the CTV that lies within 97% and 130% of the prescribed dose.

RESULTS

The results showed that the margin loss for BgRT is less than 3 mm, while for the SBRT plans were more than 3 mm when target motion is present. The dosimetric coverage for BgRT was 100% for all three cases, however less than 100% for the SBRT cases with motion. Table showing margin loss for the various experiments for a prescription dose of 10 Gy.

CONCLUSION

The results shows that BgRT is capable of tracking the tumor motion and delivering the prescribed dose to the moving target.

A Feasibility Study of Dose Band Prediction in Radiotherapy: Predicting a Dose Spectrum

PURPOSE/OBJECTIVE(S)

Current deep learning-based dose prediction methods can only predict a specific dose distribution. If the predicted dose is inaccurate, no more options can be selected. We proposed a novel dose prediction method named dose band prediction, which outcomes a spectrum of predicted dose distribution for planning and quality assurance (QA).

MATERIALS/METHODS

Upper-Band and Lower-Band losses were involved in 3D convolution neural networks to establish the Upper-Band Network (UBN) and Lower-Band Network (LBN). Each voxel's ideal dose spectrum (dose band) was defined by the maximum/minimum rational dose predicted by UBN/LBN. 130 NPC cases with Tomotherapy (dataset 1), 49 cervix cases with IMRT (dataset 2) and 43 cervix cases with VMAT (dataset 3) were enrolled to establish and evaluate our dose band prediction method.

RESULTS

The dose band prediction method can successfully predict a spectrum of doses. Upper-Band/Lower-Band presents maximum/minimum rational dose; Middle-Line presents the average of Upper-Band and Lower-Band. The clinical implement dose was used as the reference dose. We evaluated the maximum interval between the reference and Upper-Band/Middle-Line/Lower-Band doses, and the percentage dose difference was used as the evaluation method. The differences in PTV for Upper-Band, Middle-Line and Lower-Band in dataset 1 were within 2.47%, 0.54%, and 2.8%; in dataset 2, they were within 0.37%, 1.15%, and 2.69%; in dataset 3, they were within 0.96%, 0.35%, and 1.66%. The mean difference of OARs for the Upper-Band, Middle-Line and Lower-Band in dataset 1 were within 8.13%, 4.97%, and 8.19%; in dataset 2, they were within 8.8%, 4.48%, and 5.52%; in dataset 3, they were within 4.01%, 3.13%, and 5.79% (shown in Table 1).

CONCLUSION

Dose Band prediction achieved high-accuracy dose prediction by the Middle-Line. More importantly, the Upper-Band/Lower-Band provided a spectrum of possible rational doses. Our Dose Band prediction method is based on a specific loss function, so it can easily be applied in various network and patient cases. Dose Band prediction towards a more robust plan QA and planning assistance. Table 1. The maximum interval of doses (percentage dose difference, %).

Characterization of Biology-Guided Radiotherapy Accuracy as a Function of PET Tracer Uptake

PURPOSE/OBJECTIVE(S)

To characterize the tracking capability and dosimetric accuracy of biology-guided radiotherapy (BgRT) under clinically relevant PET tracer uptake scenarios relative to the background.

MATERIALS/METHODS

A custom-made anthropomorphic phantom filled with a liquid 18F-FDG solution including two embedded fillable 22 mm diameter spherical structures mimicking GTV (= CTV) and OAR was coupled to motion stages to create an independent 3D respiratory motion with 22 mm maximum range for target and a 5 mm 1D sinusoidal motion in the OAR. The biology-tracking zone (BTZ) was generated by adding 5 mm margin to the motion extent. The three BgRT scenarios studied were representative of tumors with good (8:1), borderline (4:1) and undesired (2:1) PET biodistributions compared to background. The clinical safety limit of BgRT uses Activity Concentration within the BTZ (AC ≥ 5 kBq/ml) and Normalized Target Signal as a contrast metric (NTS ≧ 2.7 for planning and ≧ 2 for delivery). The BgRT deliveries were repeated 3 times with radiochromic film and integrated ion chamber capturing the target and OAR doses. Tracked dosimetry was assessed using a margin-loss calculation defined as the maximum linear difference in distance between the planned and delivered 97% prescription iso-dose lines.

RESULTS

The imaging-only PET images used to create BgRT plans had an AC of 7.0, 5.3, and 1.6 kBq/ml with an NTS of 6.8, 5.3, and 1.8 for 8:1, 4:1, and 2:1 concentrations, respectively. Qualitatively, the target was not visible on the planning PET images 2:1 loading scenario. At delivery, the mean pre-scan activity concentrations were 6.8, 4.7, and 3.7 kBq/ml with corresponding mean NTS of 3.7, 2.6, 1.5 for 8:1, 4:1 and 2:1 deliveries. The pre-scan values of AC or NTS did not satisfy the clinical system safety limits for 4:1 and 2:1 ratio experiments, but the engineering software allowed for the delivery to capture the resulting doses. The deliveries showed a prescription dose coverage to the CTV of 100% for the 8:1 and 4:1 cases, but 88% for the 2:1 case. When compared to the planned dose values, the delivered minimum doses were -7.6%, -8.6% and -10.9%, whereas the maximum dose differences in CTV were 1.2%, 0% and -4.8% of the planned dose distributions of the 8:1, 4:1 and 2:1 cases, respectively. Calculated margin losses were -2.3, -3.8, and -5.5 mm, for the 8:1, 4:1, and 2:1 cases, respectively. The maximum OAR doses were less than the maximum doses predicted on the bounded DVH curves for all scenarios.

CONCLUSION

With sufficient tracer uptake in the target, BgRT can deliver tracked dosimetry for targets with a large respiratory motion profile. Both the good BgRT candidate and borderline cases produced clinically acceptable delivered doses, even though the borderline case was flagged by the clinical system safety checks. As expected, the delivered BgRT dose distributions were suboptimal with reduced tumor over background PET contrast.

Workplace bullying and suicidal ideation and behaviour: a systematic review and meta-analysis

OBJECTIVES

Suicidal ideation and behaviour are potential outcomes of workplace bullying. This review aimed to determine the extent of the association between workplace bullying and suicidal ideation and behaviour.

STUDY DESIGN

The study incorporated a systematic review and meta-analysis.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was followed to conduct a comprehensive systematic review and meta-analysis. A combination of subject terms and free words was used to search nine electronic databases. Two reviewers independently screened articles and extracted information according to the inclusion criteria. A meta-analysis was performed with averaged weighted correlations across samples using the STATA software (version 16.0) from pooled estimates of the main results from all studies.

RESULTS

In total, 25 articles of high or medium quality were included in the systematic review; 15 of these were included in the meta-analysis. The prevalence of suicidal ideation and behaviour was 18% and 4%, respectively. Individuals who experienced workplace bullying had 2.03-times and 2.67-times higher odds of reporting suicidal ideation and behaviour, respectively, after adjustment for confounding factors. Moderating and mediating factors may help reduce the risk of suicidal ideation and behaviour for individuals experiencing workplace bullying.

CONCLUSION

This study indicated that exposure to workplace bullying significantly increased the risk of suicidal ideation and behaviour.

Neuroprotective effects of Lycium barbarum polysaccharide on light-induced oxidative stress and mitochondrial damage via the Nrf2/HO-1 pathway in mouse hippocampal neurons

Light at night (LAN) induced cognitive impairment associated with oxidative stress in mice has been reported. Lycium barbarum polysaccharide (LBP) exhibits anti-tumor, anti-oxidant and neuroprotective effects, yet the neuroprotective effect on light-induced neuron damage still unclear. Here, mice exposed to LAN displayed cognitive impairment and depressive like behavior, which was reversed by LBP treatment. Meanwhile, LBP alleviated light-induced higher apoptosis and mitochondrial damage in HT-22 cells. Also, LBP prevented the decreased of mitochondrial membrane permeabilization (MMP) level in light-treated cells. Additionally, LBP demonstrated its antioxidant potential by reducing ROS production and malondialdehyde (MDA) level, while simultaneously enhancing the levels of superoxide dismutase (SOD) and glutathione peroxidases (GSH-Px) in both light-treated mice and HT-22 cells. Furthermore, the mRNA and protein expression of Nrf2 (NF-E2-related factor 2), heme oxygenease-1 (HO-1), and NAD(P)H quinone oxidoreductase (NQO1) were decreased in both light-treated mice and cells. Additionally, LBP treatment reversed light-induced the inhibition of Nrf2/HO-1 signaling pathway in both mice and cells. Moreover, Nrf2 antagonist ML385 significantly eliminated the neuroprotection of LBP on cell apoptosis, oxidative stress and mitochondrial damage in light-treated cells. These results indicate that LBP can rescue light-induced neurotoxicity in mice and HT-22 cells by activating the Nrf2/HO-1 signaling pathway.

Does Periodontitis Affect the Association of Biological Aging with Mortality?

The prevalence of periodontitis is increasing with the aging of the global population. Periodontitis has been suggested to accelerate aging and increase mortality. The present nationwide prospective cohort study aimed to determine whether periodontitis could modify the association of biological aging with all-cause and cause-specific mortality in middle-aged and older adults. Participants ≥40 y of age from the Third National Health and Nutrition Examination Survey (NHANES III) were included (n = 6,272). Phenotypic age acceleration (PhenoAgeAccel) was used to evaluate the biological aging process. Moderate/severe periodontitis was defined using a half-reduced Centers for Disease Control and Prevention and American Academy of Periodontology case definition. Multivariable Cox proportional hazard regression was conducted to estimate the association between PhenoAgeAccel and mortality risk, followed by effect modification analysis to test whether periodontitis modified the association. During a median follow-up of 24.5 y, 3,600 (57.4%) deaths occurred. The positive relationships between PhenoAgeAccel and all-cause and cause-specific mortality were nonlinear. After adjusting for potential confounders, the highest quartile of PhenoAgeAccel was associated with increased all-cause mortality in individuals with no/mild periodontitis (hazard ratio for Q4 vs. Q1 [HR_Q4vs.Q1] = 1.789; 95% confidence interval [CI], 1.541-2.076). In contrast, the association was enhanced in patients with moderate/severe periodontitis (HR_Q4vs.Q1 = 2.446 [2.100-2.850]). Periodontal status significantly modified the association between PhenoAgeAccel and all-cause mortality (P for interaction = 0.012). In subgroup analyses, the modifying effect of periodontitis was observed in middle-aged adults (40-59 y), females, and non-Hispanic Whites. Although cause-specific mortality showed a similar trend, the PhenoAgeAccel × periodontitis interaction did not reach statistical significance. In conclusion, periodontitis might enhance the association of biological aging with all-cause mortality in middle-aged and older adults. Hence, maintaining and enhancing periodontal health is expected to become an intervention to slow aging and extend life span.

FRUCTOSE INSENSITIVE1 regulates stem cell function in Arabidopsis in response to fructose signalling

Stem cell function in different meristems of Arabidopsis is mainly defined by WUSCHEL (WUS)/WUSCHEL-RELATED HOMEOBOX (WOX) family of proteins. Sugars have also been demonstrated to play pivotal roles in stem cell function and development of plants. As a cytosolic fructose 1,6-bisphosphatase, FRUCTOSE INSENSITIVE1 (FINS1) has been demonstrated to regulate plant growth in response to fructose signalling. However, it remains to be elucidated how stem cell function is regulated in response to fructose signalling. Our work showed that FINS1 interacts with WUS/WOX protein as a complex, which further binds to the promoter of WUS/WOX and regulates its expression in response to fructose signalling. FINS1 might act as a bifunctional factor that promotes WUS/WOX expression in the presence of low concentrations of fructose, and represses WUS/WOX expression in the presence of high concentrations of fructose. Therefore, FINS1 regulates stem cell function in response to fructose signalling during the growth and development of Arabidopsis.

Prevotella intermedia Aggravates Subclinical Hypothyroidism

Subclinical hypothyroidism (SCH) has been shown to be associated with microbiota. However, the association between SCH and oral microbiota has not yet been elucidated. The results of our previous clinical studies showed that Prevotella intermedia was abundant in the oral microbiota of SCH patients. This study aimed to investigate the relationship between SCH and oral microbiota, verify the pathogenicity of P. intermedia in SCH, and preliminarily explore the possible mechanism. The SCH mouse model with oral application of P. intermedia was established, and the variance in the mouse oral microbiota and changes in thyroid function and metabolism were detected in mice. Student's t test and analysis of variance were used for statistical analysis. Oral application of P. intermedia changed the composition of the oral microbiota of SCH mice, which enhanced the damage to the thyroid and decreased the expression of functional genes of the thyroid. Moreover, P. intermedia decreased oxygen consumption and aggravated glucose and lipid metabolism disorders in SCH mice. Glucose tolerance and insulin tolerance decreased, and the triglyceride content of the liver and inflammatory infiltration in adipose tissue increased in SCH mice after P. intermedia stimulation. Mechanistically, P. intermedia increased the proportion of CD4⁺ T cells in cervical lymph nodes and thyroids in SCH mice. Th1 cells were suggested to play an important role in the pathogenesis of SCH involving P. intermedia. In conclusion, P. intermedia aggravated SCH manifestations, including thyroid dysfunction and glucose and lipid metabolism disorders, by causing immune imbalance in mice. This study sheds new light on the pathogenesis of SCH from the perspective of oral microbiota.

Octahedral Distortion and Displacement-Type Ferroelectricity with Switchable Photovoltaic Effect in a 3d^{3}-Electron Perovskite System

Because of the half-filled t_{2g}-electron configuration, the BO_{6} octahedral distortion in a 3d^{3} perovskite system is usually very limited. In this Letter, a perovskitelike oxide Hg_{0.75}Pb_{0.25}MnO_{3} (HPMO) with a 3d^{3} Mn^{4+} state was synthesized by using high pressure and high temperature methods. This compound exhibits an unusually large octahedral distortion enhanced by approximately 2 orders of magnitude compared with that observed in other 3d^{3} perovskite systems like RCr^{3+}O_{3} (R=rare earth). Essentially different from centrosymmetric HgMnO_{3} and PbMnO_{3}, the A-site doped HPMO presents a polar crystal structure with the space group Ama2 and a substantial spontaneous electric polarization (26.5  μC/cm^{2} in theory) arising from the off-center displacements of A- and B-site ions. More interestingly, a prominent net photocurrent and switchable photovoltaic effect with a sustainable photoresponse were observed in the current polycrystalline HPMO. This Letter provides an exceptional d^{3} material system which shows unusually large octahedral distortion and displacement-type ferroelectricity violating the "d^{0}-ness" rule.

Bacterial antibiotic resistance among cancer inpatients in China: 2016-20

BACKGROUND

The incidence of infections among cancer patients is as high as 23.2-33.2% in China. However, the lack of information and data on the number of antibiotics used by cancer patients is an obstacle to implementing antibiotic management plans.

AIM

This study aimed to investigate bacterial infections and antibiotic resistance in Chinese cancer patients to provide a reference for the rational use of antibiotics.

DESIGN

This was a 5-year retrospective study on the antibiotic resistance of cancer patients.

METHODS

In this 5-year surveillance study, we collected bacterial and antibiotic resistance data from 20 provincial cancer diagnosis and treatment centers and three specialized cancer hospitals in China. We analyzed the resistance of common bacteria to antibiotics, compared to common clinical drug-resistant bacteria, evaluated the evolution of critical drug-resistant bacteria and conducted data analysis.

FINDINGS

Between 2016 and 2020, 216 219 bacterial strains were clinically isolated. The resistance trend of Escherichia coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, cefotaxime, piperacillin/tazobactam and imipenem was relatively stable and did not significantly increase over time. The resistance of Pseudomonas aeruginosa strains to all antibiotics tested, including imipenem and meropenem, decreased over time. In contrast, the resistance of Acinetobacter baumannii strains to carbapenems increased from 4.7% to 14.7%. Methicillin-resistant Staphylococcus aureus (MRSA) significantly decreased from 65.2% in 2016 to 48.9% in 2020.

CONCLUSIONS

The bacterial prevalence and antibiotic resistance rates of E. coli, K. pneumoniae, P. aeruginosa, A. baumannii, S. aureus and MRSA were significantly lower than the national average.

[Malaria control knowledge and behaviors and their influencing factors among residents in Banlao Township, Cangyuan County, Yunnan Province]

OBJECTIVE

To investigate the awareness of malaria-related knowledge, the use of mosquito nets and their influencing factors among residents in Banlao Township, Cangyuan County, Yunnan Province.

METHODS

In August 2020, 19 settlement sites in Banlao Township, Cangyuan County, Lincang City, Yunnan Province were selected as study areas, and permanent residents at ages of 10 years and older were enrolled for a questionnaire survey, including residents' demographics, family economic status, malaria control knowledge and use of mosquito nets. In addition, the factors affecting the use of mosquito nets in the night prior to the survey were identified using multivariate logistic regression analysis.

RESULTS

A total of 320 questionnaires were allocated, and all were recovered (a 100% recovery rate). There were 316 valid questionnaires, with an effective recovery rate of 98.75%. The 316 respondents included 152 men and 164 women and 250 Chinese respondents and 66 foreign respondents. The awareness of clinical syndromes of malaria was significantly higher among Chinese residents (71.60%) than among foreign residents (50.00%) (χ² = 11.03, P < 0.01), and the proportions of Chinese and foreign residents sleeping under mosquito nets were 46.00% and 69.70% on the night prior to the survey, respectively (χ² = 11.73, P < 0.01). Multivariate logistic regression analysis identified ethnicity group and type of residence as factors affecting the use of mosquito nets in the night prior to the survey.

CONCLUSIONS

The awareness of malaria control knowledge, the coverage and the use of mosquito nets were low among residents in Banlao Township, Cangyuan County, Yunnan Province. Targeted health education is recommended to improve the awareness of malaria control knowledge and self-protection ability. In addition, improving the allocation of long-lasting mosquito nets and health education pertaining to their uses and increasing the proportion of using mosquito nets correctly is needed to prevent re-establishment of imported malaria.

Cationic Nanoparticle-Stabilized Vaccine Delivery System for the H9N2 Vaccine to Promote Immune Response in Chickens

Chinese yam polysaccharides (CYPs) have received wide attention for their immunomodulatory activity. Our previous studies had discovered that the Chinese yam polysaccharide PLGA-stabilized Pickering emulsion (CYP-PPAS) can serve as an efficient adjuvant to trigger powerful humoral and cellular immunity. Recently, positively charged nano-adjuvants are easily taken up by antigen-presenting cells, potentially resulting in lysosomal escape, the promotion of antigen cross-presentation, and the induction of CD8 T-cell response. However, reports on the practical application of cationic Pickering emulsions as adjuvants are very limited. Considering the economic damage and public-health risks caused by the H9N2 influenza virus, it is urgent to develop an effective adjuvant for boosting humoral and cellular immunity against influenza virus infection. Here, we applied polyethyleneimine-modified Chinese yam polysaccharide PLGA nanoparticles as particle stabilizers and squalene as the oil core to fabricate a positively charged nanoparticle-stabilized Pickering emulsion adjuvant system (PEI-CYP-PPAS). The cationic Pickering emulsion of PEI-CYP-PPAS was utilized as an adjuvant for the H9N2 Avian influenza vaccine, and the adjuvant activity was compared with the Pickering emulsion of CYP-PPAS and the commercial adjuvant (aluminum adjuvant). The PEI-CYP-PPAS, with a size of about 1164.66 nm and a ζ potential of 33.23 mV, could increase the H9N2 antigen loading efficiency by 83.99%. After vaccination with Pickering emulsions based on H9N2 vaccines, PEI-CYP-PPAS generated higher HI titers and stronger IgG antibodies than CYP-PPAS and Alum and increased the immune organ index of the spleen and bursa of Fabricius without immune organ injury. Moreover, treatment with PEI-CYP-PPAS/H9N2 induced CD4⁺ and CD8⁺ T-cell activation, a high lymphocyte proliferation index, and increased cytokine expression of IL-4, IL-6, and IFN-γ. Thus, compared with the CYP-PPAS and aluminum adjuvant, the cationic nanoparticle-stabilized vaccine delivery system of PEI-CYP-PPAS was an effective adjuvant for H9N2 vaccination to elicit powerful humoral and cellular immune responses.

Astragalus polysaccharides combined with simvastatin as an immunostimulant enhances the immune adjuvanticity of oil-in-water emulsion and immune responses in mice

Oil-in-water emulsion-based adjuvants have demonstrated acceptable safety in many disease indications, while their adjuvant activities for vaccines still need to be improved. Recently, the strategy of combining adjuvants with multiple types of immunostimulants has been shown to enhance immune responses. In this study, astragalus polysaccharides were combined with simvastatin as an immunostimulant to construct a compound O/W emulsion adjuvant. The formulations were optimized according to the OVA-specific antibody responses induced in mice. For this reason, high (5 mg/mL), medium (2.5 mg/mL), and low (1.25 mg/mL) concentrations of astragalus polysaccharides and high (10 mg/mL), medium (1 mg/mL), and low (0.1 mg/mL) concentrations of simvastatin were selected. The final optimal formulation of the immunostimulant was a high concentration of astragalus polysaccharides combined with a medium concentration of simvastatin. The optimal compound O/W emulsion adjuvant could induce effective humoral and cellular immune responses that were stronger and more stable than those induced by aluminum adjuvant and Freund's adjuvant. The OVA/HAPS-MSim-OE induced dramatically strong and persistent IgG expressions and Th1-polarized immune responses. What's more, the highest CD4⁺/CD8⁺lymphocyte ratios were observed in OVA/HAPS-MSim-OE group. In addition, compound O/W emulsion adjuvant groups significantly promoted the secretion of IFN-γ and IL-6, which also indicated that the compound O/W emulsion adjuvants could induce both enhanced Th1 and Th2-mediated immune responses but prefer the Th1-mediated ones. This study would contribute to an interesting and promising direction in the development of emulsion-based adjuvants.

Structure of a Pueraria root polysaccharide and its immunoregulatory activity on T and B lymphocytes, macrophages, and immunosuppressive mice

In this experiment, the polysaccharide was extracted from Pueraria lobata (Willd.) Ohwi, and its structural characteristics and bioactivity were investigated. The results showed that Pueraria lobata polysaccharide (PLP) was composed of fucose, arabinose, galactose, glucose, xylose, mannose in a molar proportion of 0.09:1.25:2.19:95.74:0.43:0.30 with a number molar masses (Mn) weight of 14.463 kDa. Besides, FT-IR, Methylation, and NMR analysis revealed that PLP were mainly composed of the main chain →4)-α-Glcp (1→ and →4,6)-α-Glcp (1→, and the branched chain α-Glcp (1→. In vitro experiment, the results showed that PLP could stimulate the expression of surface molecules on RAW264.7 and (T and B) lymphocytes proliferation, simultaneously to stimulate their cytokines secretion. In vivo experiment, the immune organ index, cytokine content, and T lymphocyte subtype in cyclophosphamide-induced immunosuppressed mice could be improved by PLP. These data proved that PLP could be used as a useful immunomodulator to enhance the immune activity of RAW264.7, T, and B cells and improve the immune function of cyclophosphamide-treated mice.

[Changes in percentage of GATA3+ regulatory T cells and their pathogenic roles in allergic rhinitis]

OBJECTIVE

To investigate the changes in percentage of GATA3⁺ regulatory T (Treg) cells in patients with allergic rhinitis (AR) and mouse models.

METHODS

The nasal mucosa specimens were obtained from 6 AR patients and 6 control patients for detection of nasal mucosal inflammation. Peripheral blood mononuclear cells (PBMC) were collected from 12 AP patients and 12 control patients to determine the percentages of Treg cells and GATA3⁺ Treg cells. In a C57BL/6 mouse model of AR, the AR symptom score, peripheral blood OVA-sIgE level, and nasal mucosal inflammation were assessed, and the spleen of mice was collected for detecting the percentages of Treg cells and GATA3⁺ Treg cells and the expressions of Th2 cytokines.

RESULTS

Compared with the control patients, AR patients showed significantly increased eosinophil infiltration and goblet cell proliferation in the nasal mucosa (P < 0.01) and decreased percentages of Treg cells and GATA3⁺ Treg cells (P < 0.05). The mouse models of AR also had more obvious allergic symptoms, significantly increased OVA-sIgE level in peripheral blood, eosinophil infiltration and goblet cell hyperplasia (P < 0.01), markedly lowered percentages of Treg cells and GATA3⁺ Treg cells in the spleen (P < 0.01), and increased expressions of IL-4, IL-6 and IL-10 (P < 0.05).

CONCLUSION

The percentage of GATA3⁺ Treg cells is decreased in AR patients and mouse models. GATA3⁺ Treg cells possibly participate in Th2 cell immune response, both of which are involved in the occurrence and progression of AR, suggesting the potential of GATA3⁺ Treg cells as a new therapeutic target for AR.

Negative refraction in hyperbolic hetero-bicrystals

We visualized negative refraction of phonon polaritons, which occurs at the interface between two natural crystals. The polaritons-hybrids of infrared photons and lattice vibrations-form collimated rays that display negative refraction when passing through a planar interface between the two hyperbolic van der Waals materials: molybdenum oxide (MoO₃) and isotopically pure hexagonal boron nitride (h¹¹BN). At a special frequency ω₀, these rays can circulate along closed diamond-shaped trajectories. We have shown that polariton eigenmodes display regions of both positive and negative dispersion interrupted by multiple gaps that result from polaritonic-level repulsion and strong coupling.

Ultra-low-dose CT lung screening with artificial intelligence iterative reconstruction: evaluation via automatic nodule-detection software

AIM

To test the feasibility of ultra-low-dose (ULD) computed tomography (CT) combined with an artificial intelligence iterative reconstruction (AIIR) algorithm for screening pulmonary nodules using computer-assisted diagnosis (CAD).

MATERIALS AND METHODS

A chest phantom with artificial pulmonary nodules was first scanned using the routine protocol and the ULD protocol (3.28 versus 0.18 mSv) to compare the image quality and to test the acceptability of the ULD CT protocol. Next, 147 lung-screening patients were enrolled prospectively, undergoing an additional ULD CT immediately after their routine CT examination for clinical validation. Images were reconstructed with filtered back-projection (FBP), hybrid iterative reconstruction (HIR), the AIIR, and were imported to the CAD software for preliminary nodule detection. Subjective image quality on the phantom was scored using a five-point scale and compared using the Mann-Whitney U-test. Nodule detection using CAD was evaluated for ULD HIR and AIIR images using the routine dose image as reference.

RESULTS

Higher image quality was scored for AIIR than for FBP and HIR at ULD (p<0.001). As reported by CAD, 107 patients were presented with more than five nodules on routine dose images and were chosen to represent the challenging cases at an early stage of pulmonary disease. Among such, the performance of nodule detection by CAD on ULD HIR and AIIR images was 75.2% and 92.2% of the routine dose image, respectively.

CONCLUSION

Combined with AIIR, it was feasible to use an ULD CT protocol with 95% dose reduction for CAD-based screening of pulmonary nodules.

Endotyping of nasal polyps in a multiracial Asian population

Background: Chronic rhinosinusitis is a heterogenous disease with variation in the endotypes of nasal polyps, with type 2 inflammation being more prevalent in Caucasian populations whereas Chinese populations are more heterogenous. We aim to describe the variation in endotypes for patients with chronic rhinosinusitis with nasal polyposis in our unique multiracial population. Methodology: Demographic, clinical and structured histopathological data of 66 patients who underwent sinus surgery for nasal polyposis were evaluated retrospectively. Results: 54.6% had eosinophilic disease, and 45.4% had non-eosinophilic disease with no significant demographic differences between the 2 populations. There were significantly higher peripheral eosinophil levels in patients with eosinophil-predominant inflammation on tissue histology (mean absolute eosinophil count 0.59 ± 0.18 x 109) compared with non-eosinophilic disease (mean absolute eosinophil count 0.24 ± 0.11 x 109). Structured histopathological reporting revealed that patients with eosinophilic disease had higher degree of inflammation and eosinophil aggregates. Conclusions: Our population is shown to have a slight preponderance toward eosinophilic disease, however the Chinese majority tended to have non-eosinophilic disease. Serum eosinophilia and the presence of asthma seems to correlate well with tissue eosinophilia, which can potentially be utilised as markers of type 2 inflammatory disease.

Identification of key gene networks controlling polysaccharide accumulation in different tissues of Polygonatum cyrtonema Hua by integrating metabolic phenotypes and gene expression profiles

Plant polysaccharides, a type of important bioactive compound, are involved in multiple plant defense mechanisms, and in particular polysaccharide-alleviated abiotic stress has been well studied. Polygonatum cyrtonema Hua (P. cyrtonema Hua) is a medicinal and edible perennial plant that is used in traditional Chinese medicine and is rich in polysaccharides. Previous studies suggested that sucrose might act as a precursor for polysaccharide biosynthesis. However, the role of sucrose metabolism and transport in mediating polysaccharide biosynthesis remains largely unknown in P. cyrtonema Hua. In this study, we investigated the contents of polysaccharides, sucrose, glucose, and fructose in the rhizome, stem, leaf, and flower tissues of P. cyrtonema Hua, and systemically identified the genes associated with the sucrose metabolism and transport and polysaccharide biosynthesis pathways. Our results showed that polysaccharides were mainly accumulated in rhizomes, leaves, and flowers. Besides, there was a positive correlation between sucrose and polysaccharide content, and a negative correlation between glucose and polysaccharide content in rhizome, stem, leaf, and flower tissues. Then, the transcriptomic analyses of different tissues were performed, and differentially expressed genes related to sucrose metabolism and transport, polysaccharide biosynthesis, and transcription factors were identified. The analyses of the gene expression patterns provided novel regulatory networks for the molecular basis of high accumulation of polysaccharides, especially in the rhizome tissue. Furthermore, our findings explored that polysaccharide accumulation was highly correlated with the expression levels of SUS, INV, SWEET, and PLST, which are mediated by bHLH, bZIP, ERF, ARF, C2H2, and other genes in different tissues of P. cyrtonema Hua. Herein, this study contributes to a comprehensive understanding of the transcriptional regulation of polysaccharide accumulation and provides information regarding valuable genes involved in the tolerance to abiotic stresses in P. cyrtonema Hua.