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1.
PLoS Genet ; 20(7): e1011358, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38991029

ABSTRACT

Heterochromatin is critical for maintaining genome stability, especially in flowering plants, where it relies on a feedback loop involving the H3K9 methyltransferase, KRYPTONITE (KYP), and the DNA methyltransferase CHROMOMETHYLASE3 (CMT3). The H3K9 demethylase INCREASED IN BONSAI METHYLATION 1 (IBM1) counteracts the detrimental consequences of KYP-CMT3 activity in transcribed genes. IBM1 expression in Arabidopsis is uniquely regulated by methylation of the 7th intron, allowing it to monitor global H3K9me2 levels. We show the methylated intron is prevalent across flowering plants and its underlying sequence exhibits dynamic evolution. We also find extensive genetic and expression variations in KYP, CMT3, and IBM1 across flowering plants. We identify Arabidopsis accessions resembling weak ibm1 mutants and Brassicaceae species with reduced IBM1 expression or deletions. Evolution towards reduced IBM1 activity in some flowering plants could explain the frequent natural occurrence of diminished or lost CMT3 activity and loss of gene body DNA methylation, as cmt3 mutants in A. thaliana mitigate the deleterious effects of IBM1.


Subject(s)
Arabidopsis Proteins , Arabidopsis , DNA Methylation , Evolution, Molecular , Gene Expression Regulation, Plant , Heterochromatin , Heterochromatin/genetics , Heterochromatin/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Arabidopsis/genetics , DNA Methylation/genetics , Jumonji Domain-Containing Histone Demethylases/genetics , Jumonji Domain-Containing Histone Demethylases/metabolism , Introns/genetics , Histones/metabolism , Histones/genetics , Mutation , DNA-Cytosine Methylases/metabolism , DNA-Cytosine Methylases/genetics , Genomic Instability
3.
Ultrason Sonochem ; 108: 106967, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38917596

ABSTRACT

The transformation of salvianolic acid B brought on by heat treatment recovery of ethanol eluent, which is a difficult problem in pharmaceutical technology, affects the purity of raw material when the medicinal raw material salvianolic acid B is purified by resin. Ultrasonic-assisted nanofiltration separation (UANS) was first employed to improve efficiency of resource utilization by regulating rejection and separating salvianolic acid B and rosmarinic acid from organic pharmaceutical wastewater. The rejection was related to three variables: ultrasonic power, pH, and ethanol concentration. But there were differences in the effects of variables on the rejections of salvianolic acid B and rosmarinic acid. The rejections of rosmarinic acid and salvianolic acid B showed a decreasing trend with an increase in ultrasonic power or a decrease in pH; however, when the concentration of ethanol was increased from 5 % to 35 %, the salvianolic acid B rejection increased from 84.96 % to 96.60 % and the rosmarinic acid rejection decreased from 35.09 % to 17.51 %. On the basis of response surface methodology (RSM), the optimal UANS parameters for solution conditions involving different ethanol concentrations are as follows: 10 % ethanol solution (ultrasonic power 500 W and pH 6.15), 20 % ethanol solution (ultrasonic power 500 W and pH 6.54), and 30 % ethanol solution (ultrasonic power 460 W and pH 6.34). The molecular proportions of salvianolic acid B were 10.75 %, 7.13 %, and 8.27 % in 10 %, 20 %, and 30 % ethanol wastewater, while the molecular proportions of rosmarinic acid were 40.52 %, 33.83 %, and 69.87 %, respectively. And the recoveries of salvianolic acid B in 10 %, 20 %, and 30 % ethanol wastewater were 93.56 %, 95.04 %, and 97.30 %, respectively, while the recoveries of rosmarinic acid were 3.19 %, 2.27 %, and 0.56 %. The molecular proportion and the rejection are correlated exponentially. In comparison with conventional nanofiltration separation (CNS), UANS is able to resolve the conflict between rosmarinic acid and salvianolic acid B in pharmaceutical wastewater, as well as enhance resource recycling and separation efficiency to prevent pollution of the environment from pharmaceutical wastewater. Experiments using UANS at different power intensities suggest that the ultrasonic at a power intensity of 46-50 W/L and the power density of 0.92-1.00 W/cm2 may resolve the separation conflict between rosmarinic acid and salvianolic acid B. This work suggests that UANS may be a significant advancement in the field of ultrasonic separation and has several potential uses in the water treatment industry.


Subject(s)
Benzofurans , Ethanol , Filtration , Wastewater , Wastewater/chemistry , Benzofurans/isolation & purification , Ethanol/chemistry , Filtration/methods , Nanotechnology/methods , Depsides/isolation & purification , Depsides/chemistry , Rosmarinic Acid , Hydrogen-Ion Concentration , Ultrasonic Waves , Cinnamates/isolation & purification , Cinnamates/chemistry
4.
Macromol Rapid Commun ; : e2400336, 2024 Jun 23.
Article in English | MEDLINE | ID: mdl-38924226

ABSTRACT

Poly(ethylene glycol) (PEG) or oligo (ethylene glycol) (OEG) grafted anion exchange membranes (AEMs) exhibit improved ionic conductivity, high alkaline stability, and subsequent boosted AEM fuel cell performance, but too much PEG/OEG side chains may can result in a reduction in the ion exchange capacity (IEC), which can have adverse effects on ion transport. Here, a series of partially PEG-grafted poly(terphenyl piperidinium) with different side chain length are synthesized using simple postpolymerization modification to produce AEMs with balanced properties. The polar and flexible PEG side chains are responsible for the controlled water uptake and swelling, superior hydroxide conductivity (122 mS cm-1 at 80 °C with an IEC of 1.99 mmol g-1), and enhanced alkaline stability compared to the reference sample without PEG grafts (PTP). More importantly, the performance of AEM fuel cell (AEMFC) with the membrane containing partial PEG side chains surpasses that with PTP membrane, demonstrating a highest peak power density of 1110 mW cm-2 at 80 °C under optimized conditions. This work provides a novel approach to the fabrication of high-performance AEM materials with balanced properties for alkaline fuel cell application.

5.
Article in English | MEDLINE | ID: mdl-38713571

ABSTRACT

Text-to-image generation models have significantly broadened the horizons of creative expression through the power of natural language. However, navigating these models to generate unique concepts, alter their appearance, or reimagine them in unfamiliar roles presents an intricate challenge. For instance, how can we exploit language-guided models to transpose an anime character into a different art style, or envision a beloved character in a radically different setting or role? This paper unveils a novel approach named DreamAnime, designed to provide this level of creative freedom. Using a minimal set of 2-3 images of a user-specified concept such as an anime character or an art style, we teach our model to encapsulate its essence through novel "words" in the embedding space of a pre-existing text-to-image model. Crucially, we disentangle the concepts of style and identity into two separate "words", thus providing the ability to manipulate them independently. These distinct "words" can then be pieced together into natural language sentences, promoting an intuitive and personalized creative process. Empirical results suggest that this disentanglement into separate word embeddings successfully captures a broad range of unique and complex concepts, with each word focusing on style or identity as appropriate. Comparisons with existing methods illustrate DreamAnime's superior capacity to accurately interpret and recreate the desired concepts across various applications and tasks. Code is available at https://github.com/chnshx/DreamAnime.

6.
Cont Lens Anterior Eye ; : 102192, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38806328

ABSTRACT

PURPOSE: To investigate bilateral axial length (AL) growth patterns and interactions of myopic eyes in anisometropic children during unilateral orthokeratology (OK) treatment in their singularly myopic eyes (Eyes1), followed by bilateral treatment when their second eyes (Eyes2) developed myopia. METHODS: This study enrolled 94 eyes from 47 anisometropes (20 males). All patients had undergone monocular OK treatment for > 1 year followed by binocular treatment for > 1 year. Axial growth of Eyes1 and Eyes2 during the first year of monocular treatment (Stage 1), average annual axial elongation during the monocular treatment period, and axial elongation during the first year of binocular treatment (Stage 2) were respectively termed: S1E1 and S1E2, Annual E1 and Annual E2, and S2E1 and S2E2. Associations between AL growth and age, sex, interval time, and ocular parameters were analysed using correlation and generalised estimating equation (GEE) analysis. RESULTS: During the monocular period, Eyes1 showed less AL growth (S1E1: 0.05 ± 0.18 mm; Annual E1: 0.05 ± 0.21 mm) than Eyes2 (S1E2: 0.51 ± 0.24 mm; Annual E2: 0.52 ± 0.25 mm) (all p < 0.001). During the binocular period, there was no significant difference between S2E1 and S2E2(0.21 ± 0.14 mm v. 0.19 ± 0.17 mm, p = 0.951). Between monocular and binocular periods, Eyes1 had significantly higher S2E1 compared to S1E1 and Annual E1 (both p < 0.001), and Eyes2 had significantly lower S2E2 than S1E2 and Annual E2 (both p < 0.001). In the GEE model, spherical equivalent refraction (SER) and between periods interval time showed independently significant associations with AL growth after adjusting for age and sex. CONCLUSION: Orthokeratology can significantly control AL growth in unilateral myopia. AL growth of the initial myopic OK-treated eyes accelerated relative to the monocular period when contralateral eyes developed myopia and assumed OK treatment. During the binocular treatment phase, OK lenses showed moderate and comparable effects on AL retardation across both eyes.

7.
J Cell Mol Med ; 28(8): e18285, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38597406

ABSTRACT

Microglial polarization and associated inflammatory activity are the key mediators of depression pathogenesis. The natural Smilax glabra rhizomilax derivative engeletin has been reported to exhibit robust anti-inflammatory activity, but no studies to date have examined the mechanisms through which it can treat depressive symptoms. We showed that treatment for 21 days with engeletin significantly alleviated depressive-like behaviours in chronic stress social defeat stress (CSDS) model mice. T1-weighted imaging (T1WI), T2-weighted imaging (T2WI) imaging revealed no significant differences between groups, but the bilateral prefrontal cortex of CSDS mice exhibited significant increases in apparent diffusion coefficient and T2 values relative to normal control mice, with a corresponding reduction in fractional anisotropy, while engeletin reversed all of these changes. CSDS resulted in higher levels of IL-1ß, IL-6, and TNF-a production, enhanced microglial activation, and greater M1 polarization with a concomitant decrease in M2 polarization in the mPFC, whereas engeletin treatment effectively abrogated these CSDS-related pathological changes. Engeletin was further found to suppress the LCN2/C-X-C motif chemokine ligand 10 (CXCL10) signalling axis such that adeno-associated virus-induced LCN2 overexpression ablated the antidepressant effects of engeletin and reversed its beneficial effects on the M1/M2 polarization of microglia. In conclusion, engeletin can alleviate CSDS-induced depressive-like behaviours by regulating the LCN2/CXCL10 pathway and thereby altering the polarization of microglia. These data suggest that the antidepressant effects of engeletin are correlated with the polarization of microglia, highlighting a potential avenue for future design of antidepressant strategies that specifically target the microglia.


Subject(s)
Antidepressive Agents , Flavonols , Glycosides , Microglia , Mice , Animals , Microglia/metabolism , Antidepressive Agents/pharmacology , Antidepressive Agents/therapeutic use , Depression/drug therapy , Depression/etiology , Signal Transduction
8.
Biomedicines ; 12(3)2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38540274

ABSTRACT

The emergence of castration-resistant prostate cancer (CRPC) following androgen deprivation therapy (ADT) is associated with increased malignancy and limited treatment options. This study aims to investigate potential connections between immune cell infiltration and inflammatory cytokines with the YAP1/AR/PSA axis by exploring their interactions with autophagy. Our research reveals heightened levels of Yes-associated protein 1 (YAP1) expression in CRPC tissues compared with tissues from androgen-dependent prostate cancer (ADPC) and benign prostate hyperplasia (BPH). Additionally, a correlation was observed between YAP1 and PSA expressions in CRPC tissues, suggesting that YAP1 may exert a regulatory influence on PSA expression within CRPC. Enhanced YAP1 expression in C4-2 cells resulted in the upregulation of androgen receptor (AR) nuclear translocation and intracellular prostate-specific antigen (PSA) levels. Conversely, the suppression of YAP1 led to a decrease in PSA expression, suggesting that YAP1 may positively regulate the PSA in castration-resistant prostate cancer (CRPC) by facilitating AR nuclear import. The modulation of the autophagy activity exerts a significant impact on the expression levels of YAP1, the AR, and the PSA. Moreover, recent advancements in immunity and inflammation studies present promising avenues for potential therapies targeting prostate cancer (PC).

9.
Nanoscale ; 16(14): 7085-7092, 2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38488869

ABSTRACT

A fiber-optic surface plasmon resonance (SPR) biosensor based on a silver-coated hollow fiber (HF) structure for glucose detection is presented. The sensor surface was immobilized with 4-mercaptophenylboronic acid (PMBA) acting as a glucose recognition monolayer. Then, gold nanoparticles (AuNPs) modified with 2-aminoethanethiol (2-AET) and PMBA were introduced onto the sensor surface after glucose was captured to enhance the wavelength shift of the SPR phenomenon excited by the light transmitted in the wall of the HF sensor. Instead of the conventional one-step sensitization pretreatment commonly used in the deposition process of silver films for fiber-optic SPR sensors, a sensitization-activation two-step activation method was adopted in the fabrication of the proposed sensor. Experiments for glucose detection were performed on the fabricated sensors in the concentration range of 1 nM-1 mM. Results showed that the sensor fabricated by the two-step activation method has a much larger shift of resonance wavelength than the sensor fabricated using the one-step sensitization method. The resonance wavelength shift was found to be linear to the logarithm of the concentration in the range of 1 nM-1 mM. The sensor achieved a limit of detection (LOD) of as low as 1 nM, which is at least an order of magnitude lower than that of other fiber-optic sensors for glucose detection reported previously. The presented HF glucose sensor has the potential for biosensing applications and provides a large reference value in the study of optical fiber SPR sensors for biosensing.

10.
Proc Natl Acad Sci U S A ; 121(14): e2317444121, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38527208

ABSTRACT

Dust loading in West and South Asia has been a major environmental issue due to its negative effects on air quality, food security, energy supply and public health, as well as on regional and global weather and climate. Yet a robust understanding of its recent changes and future projection remains unclear. On the basis of several high-quality remote sensing products, we detect a consistently decreasing trend of dust loading in West and South Asia over the last two decades. In contrast to previous studies emphasizing the role of local land use changes, here, we attribute the regional dust decline to the continuous intensification of Arctic amplification driven by anthropogenic global warming. Arctic amplification results in anomalous mid-latitude atmospheric circulation, particularly a deepened trough stretching from West Siberia to Northeast India, which inhibits both dust emissions and their downstream transports. Large ensemble climate model simulations further support the dominant role of greenhouse gases induced Arctic amplification in modulating dust loading over West and South Asia. Future projections under different emission scenarios imply potential adverse effects of carbon neutrality in leading to higher regional dust loading and thus highlight the importance of stronger anti-desertification counter-actions such as reforestation and irrigation management.

11.
Cancer Sci ; 115(5): 1492-1504, 2024 May.
Article in English | MEDLINE | ID: mdl-38476086

ABSTRACT

Long noncoding RNAs (lncRNAs) have emerged as important molecules and potential new targets for human cancers. This study investigates the function of lncRNA CTBP1 antisense RNA (CTBP1-AS) in prostate cancer (PCa) and explores the entailed molecular mechanism. Aberrantly expressed genes potentially correlated with PCa progression were probed using integrated bioinformatics analyses. A cohort of 68 patients with PCa was included, and their tumor and para-cancerous tissues were collected. CTBP1-AS was highly expressed in PCa tissues and cells and associated with poor patient prognosis. By contrast, tumor protein p63 (TP63) and S100 calcium binding protein A14 (S100A14) were poorly expressed in the PCa tissues and cells. CTBP1-AS did not affect TP63 expression; however it blocked the TP63-mediated transcriptional activation of S100A14, thereby reducing its expression. CTBP1-AS silencing suppressed proliferation, apoptosis resistance, migration, invasion, and tumorigenicity of PCa cell lines, while its overexpression led to inverse results. The malignant phenotype of cells was further weakened by TP63 overexpression but restored following artificial S100A14 silencing. In conclusion, this study demonstrates that CTBP1-AS plays an oncogenic role in PCa by blocking TP63-mediated transcriptional activation of S100A14. This may provide insight into the management of PCa.


Subject(s)
Cell Proliferation , Disease Progression , Gene Expression Regulation, Neoplastic , Prostatic Neoplasms , RNA, Long Noncoding , Transcription Factors , Tumor Suppressor Proteins , Animals , Humans , Male , Mice , Alcohol Oxidoreductases/genetics , Alcohol Oxidoreductases/metabolism , Apoptosis/genetics , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Prognosis , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Prostatic Neoplasms/metabolism , RNA, Antisense/genetics , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Transcriptional Activation , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism
12.
Front Immunol ; 15: 1324010, 2024.
Article in English | MEDLINE | ID: mdl-38370418

ABSTRACT

Triggering receptor expressed on myeloid cells 1 (TREM1), which belongs to the Ig-like superfamily expressed on myeloid cells, is reportedly involved in various diseases but has rarely been studied in glioma. In this study, the prognostic value and functional roles of TREM2 in glioma were analyzed. TERM1 was observed to be significantly upregulated in GBM compared to in other grade gliomas and was associated with poor prognosis. Increased TREM1 accompanied distinct mutation and amplification of driver oncogenes. Moreover, gene ontology and KEGG analyses showed that TREM1 might play a role in immunologic biological processes in glioma. TREM1 was also found to be tightly correlated with immune checkpoint molecules. xCell research revealed a link between TREM1 expression and multiple immune cell types, especially monocytes and macrophages. Single-cell analysis and immunofluorescence results showed that macrophages expressed TREM1. In vitro, inhibition of TREM1 signaling could result in a decrease in tumor-promoting effects of monocytes/TAMs. In summary, TREM1 may be a potential independent prognostic factor and immune target, which might provide new avenues to improve the efficacy of immunotherapy in glioma patients.


Subject(s)
Glioma , Macrophages , Humans , Triggering Receptor Expressed on Myeloid Cells-1/genetics , Triggering Receptor Expressed on Myeloid Cells-1/metabolism , Prognosis , Macrophages/metabolism , Glioma/genetics , Glioma/metabolism , Monocytes/metabolism
13.
Ultrason Sonochem ; 103: 106781, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38281445

ABSTRACT

Ultrasonic-assisted activated carbon separation (UACS) was first employed to improve product quality by regulating adsorption rate and removing bacterial endotoxin from salvia miltiorrhizae injection. The adsorption rate was related to three variables: activated carbon dosage, ultrasonic power, and pH. With the increase of activated carbon dosage from 0.05 % to 1.0 %, the adsorption rates of salvianolic acids and bacterial endotoxin increased simultaneously. The adsorption rates at which bacteria endotoxins increased from 52.52 % to 97.16 % were much higher than salvianolic acids. As the ultrasonic power increased from 0 to 700 W, the adsorption rates of salvianolic acids on activated carbon declined to less than 10 %, but bacterial endotoxin increased to more than 87 %. As the pH increased from 2.00 to 8.00, the adsorption rate of salvianolic acid dropped whereas bacterial endotoxin remained relatively stable. On the basis of response surface methodology (RSM), the optimal separation conditions were established to be activated carbon dose of 0.70 %, ultrasonic power of 600 W, and pH of 7.90. The experimental adsorption rates of bacterial endotoxin were 94.15 %, which satisfied the salvia miltiorrhizae injection quality criterion. Meanwhile, salvianolic acids' adsorption rates were 1.92 % for tanshinol, 4.05 % for protocatechualdehyde, 2.21 % for rosmarinic acid, and 3.77 % for salvianolic acid B, all of which were much lower than conventional activated carbon adsorption (CACA). Salvianolic acids' adsorption mechanism on activated carbon is dependent on the component's molecular state. Under ideal separation conditions, the molecular states of the four salvianolic acids fall between 1.13 % and 6.60 %. The quality of salvia miltiorrhizae injection can be improved while maintaining injection safety by reducing the adsorption rates of salvianolic acids to less than 5 % by the use of ultrasound to accelerate the desorption mass transfer rate on the activated carbon surface. When activated carbon adsorption was used in the process of producing salvia miltiorrhizae injection, the pH of the solution was around 5.00, and the proportion of each component's molecular state was tanshinol 7.05 %, protocatechualdehyde 48.93 %, rosmarinic acid 13.79 %, and salvianolic acid B 10.28 %, respectively. The loss of useful components was evident, and the corresponding activated carbon adsorption rate ranged from 20.74 % to 41.05 %. The average variation rate in plasma His and IgE was significant (P < 0.05) following injection of 0.01 % activated carbon, however the average variation rate of salvia miltiorrhizae injection was dramatically decreased with the use of UACS and CACA (P > 0.05). The ultrasonic at a power intensity of 60 W/L and the power density of 1.20 W/cm2 may resolve the separation contradiction between salvianolic acids and bacterial endotoxin, according to experiments conducted with UACS at different power intensities. According to this study, UACS has a lot of potential applications in the pharmaceutical manufacturing industry and may represent a breakthrough in the field of ultrasonic separation.


Subject(s)
Alkenes , Benzaldehydes , Benzofurans , Caffeic Acids , Catechols , Depsides , Drugs, Chinese Herbal , Polyphenols , Salvia miltiorrhiza , Drugs, Chinese Herbal/chemistry , Salvia miltiorrhiza/chemistry , Charcoal , Ultrasonics , Rosmarinic Acid , Endotoxins
14.
Sci Total Environ ; 916: 170253, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38253097

ABSTRACT

Root exudates are pivotal in plant stress responses, however, the impact of microplastics (MPs) on their release and characteristics remains poorly understood. This study delves into the effects of 0.05 % and 0.1 % (w/w) additions of polyethylene (PE) MPs on the growth and physiological properties of lettuce (Lactuca sativa L.) following 28 days of exposure. The release characteristics of root exudates were assessed using UV-vis and 3D-EEM. The results indicated that PE increased leaf number but did not significantly affect other agronomic traits or pigment contents. Notably, 0.05 % PE increased the total root length and surface area compared to the 0.1 % addition, while a non-significant trend towards decreased root activity was observed with PE MPs. PE MPs with 0.1 % addition notably reduced the DOC concentration in root exudates by 37.5 %, while 0.05 % PE had no impact on DOC and DON concentrations. PE addition increased the SUVA254, SUVA260, and SUVA280 values of root exudates, with the most pronounced effect seen in the 0.05 % PE treatment. This suggests an increase of aromaticity and hydrophobic components induced by PE addition. Fluorescence Regional Integration (FRI) analysis of 3D-EEM revealed that aromatic proteins (region I and II) were dominant in root exudates, with a slight increase in fulvic acid-like substances (region III) under 0.1 % PE addition. Moreover, prolonged PE exposure induced ROS damage in lettuce leaves, evidenced by a significant increase in content and production rate of O2·-. The decrease in CAT and POD activities may account for the lettuce's response to environmental stress, potentially surpassing its tolerance threshold or undergoing adaptive regulation. These findings underscore the potential risk of prolonged exposure to PE MPs on lettuce growth.


Subject(s)
Microplastics , Plastics , Microplastics/metabolism , Plastics/metabolism , Polyethylene/metabolism , Lactuca , Hydroponics , Oxidative Stress
15.
Soft Matter ; 20(6): 1253-1262, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38235808

ABSTRACT

Small-molecular-induced intermolecular hydrogen bonding (inter-HB) interactions were reported to increase the glass transition temperature (Tg) while decrease the dynamic fragility (m) of polymers. Herein, enthalpy relaxation parameters heat capacity jump (ΔCp) at Tg and enthalpy hysteresis (ΔHR) were investigated to help clarify the effect of macromolecular-induced inter-HB on Tg and m using amorphous polyamides as model polymers. The inter-HB strength was weakened by random copolymerization with varied chain rigidity, but was enhanced by decreasing steric hindrance. It was found that Tg and m increased after copolymerization due to the increased chain rigidity. Nevertheless, increasing steric hindrance leads to an increased Tg while anomalously reduced m. Further results found that m can be well correlated to Tg·ΔCp/ΔHR. ΔCp increases more significantly than ΔHR in co-polyamides, and thus the entropy change dominates the activation free energy of cooperative rearrangement. By contrast, ΔHR increases more significantly than ΔCp with increasing steric hindrance, and thus it is reasonable that Tg increases while m decreases. Most importantly, ΔCp and ΔHR decrease with increasing inter-HB strength regardless of the variation of Tg. These results indicate that the inter-HB strength may be very strong and insensitive to temperature in polyamides, thus behaving like physical cross-linking.

16.
J Orthop Res ; 42(3): 685-699, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37794686

ABSTRACT

Traditional growing rod (TGR) provides a corrective moment for deformed segments to straighten the spine, whose clinical efficacy has proven positive and growth-friendly. However, an insufficient understanding of orthopedic mechanisms can affect the development of clinical strategies. This research attempts to analyze the spine that has undergone four distraction operations: exploring the spinal orthopedic mechanism, including alignment, growth, and morphology. In this study, the spinal morphology curves were illustrated in three human planes to exhibit the changes in spinal alignment. The spinal growth characteristics were measured to discuss the unsynchronized and diminishing growth rate. The spinal deformations were evaluated to indicate asymmetric growth. As a result, the spinal alignment changes indicated the orthopedic process improved, but the re-unbalance occurred after multiple distractions. Then, unsynchronized growth existed in the superior and inferior segments, and the growth rate over every distraction diminished. Finally, asymmetric growth was indicated as the axial/circumferential growth ratio getting greater and the cuneate level approaching normal. Accordingly, a TGR is growth-friendly, but combining the osteotomy fusion of lumbar segments for severe early-onset scoliosis may be an excellent choice to solve the insufficient corrective stimulation. Regarding the distraction process, reshaping before the final fusion can fix the balance loss, and a prolonged distraction frequency fits the law of diminishing return. In conclusion, studying orthopedic mechanisms based on morphological measurement can guide clinical strategy optimization.


Subject(s)
Orthopedic Procedures , Osteogenesis, Distraction , Scoliosis , Humans , Scoliosis/surgery , Spine/surgery , Treatment Outcome , Osteotomy , Retrospective Studies
17.
Neural Netw ; 169: 378-387, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37924607

ABSTRACT

The effective use of temporal relationships while extracting fertile spatial features is the key to video action understanding. Video action understanding is a challenging visual task because it generally necessitates not only the features of individual key frames but also the contextual understanding of the entire video and the relationships among key frames. Temporal relationships pose a challenge to video action understanding. However, existing 3D convolutional neural network approaches are limited, with a great deal of redundant spatial and temporal information. In this paper, we present a novel two-stream approach that incorporates Spatial Residual Attention and Temporal Markov (SRATM) to learn complementary features to achieve stronger video action understanding performance. Specifically, the proposed SRATM consists of spatial residual attention and temporal Markov. Firstly, the spatial residual attention network captures effective spatial feature representation. Further, the temporal Markov network enhances the model by learning the temporal relationships via conducting probabilistic logic calculation among frames in a video. Finally, we conduct extensive experiments on four video action datasets, namely, Something-Something-V1, Something-Something-V2, Diving48, and Mini-Kinetics, show that the proposed SRATM method achieves competitive results.


Subject(s)
Learning , Neural Networks, Computer , Physics
18.
Biomed Tech (Berl) ; 69(2): 151-165, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-37823389

ABSTRACT

OBJECTIVES: Fatigue has a considerable impact on the driver's vehicle and even the driver's own operating ability. METHODS: An intelligent algorithm is proposed for the problem that it is difficult to classify the degree of drowsiness generated by the driver during the driving process. By studying the driver's electrocardiogram (ECG) during driving, two models were established to jointly classify the ECG signals as awake, stress, and fatigue or drowsiness states for drowsiness levels. Firstly, the deep learning method was used to establish the model_1 to predict the drowsiness of the original ECG, and model_2 was developed using the combination of principal component analysis (PCA) and weighted K-nearest neighbor (WKNN) algorithm to classify the heart rate variability characteristics. Then, the drowsiness prediction results of the two models were weighted according to certain rules, and the hybrid learning model combining dilated convolution and bidirectional long short-term memory network with PCA and WKNN algorithm was established, and the mixed model was denoted as DiCNN-BiLSTM and PCA-WKNN (DBPW). Finally, the validity of the DBPW model was verified by simulation of the public database. RESULTS: The experimental results show that the average accuracy, sensitivity and F1 score of the test model in the dataset containing multiple drivers are 98.79, 98.81, and 98.79 % respectively, and the recognition accuracy for drowsiness or drowsiness state is 99.33 %. CONCLUSIONS: Using the proposed algorithm, it is possible to identify driver anomalies and provide new ideas for the development of intelligent vehicles.


Subject(s)
Algorithms , Wakefulness , Humans , Wakefulness/physiology , Computer Simulation , Electrocardiography , Fatigue
19.
Sci Rep ; 13(1): 21592, 2023 12 07.
Article in English | MEDLINE | ID: mdl-38062071

ABSTRACT

Ferroptosis is a form of cell death that is triggered by iron-dependent lipid peroxidation and is closely associated with osteoarthritis. The primary interventions for inhibiting ferroptosis in osteoarthritis are anti-lipid peroxidation and iron chelation. The objective of our study is to investigate the characteristics of ferroptosis in osteoarthritis and identify the optimal time points for inhibiting ferroptosis to alleviate disease progression. Ferroptosis-related alterations and markers of OA were analyzed in paired intact and damaged cartilages from OA patients by immunofluorescence, qRT-PCR, mitochondrial membrane potential and immunohistochemistry. We also compared Ferroptosis-related alterations in cartilage of mild, moderate, and severe OA (according to the modified Mankin score). In addition, we compared the effect of Fer-1 on ferroptosis and the protection of chondrocytes by detecting markers of both ferroptosis and OA by immunofluorescence, CCK8 and qRT-PCR. Ferroptosis-related alterations (GPX4 downregulation, ACSL4 upregulation, MDA, LPO accumulation, Mitochondrial membrane potential decreased) in the damaged area cartilage were more severe than those in the intact area and increased with the progression of OA. Compared with mild OA group, the activity of chondrocytes treated with Fer-1 (a ferroptosis inhibitor) was increased, mitochondrial function was improved, and ferroptosis was reduced (GPX4 upregulation, SLC7A11 upregulation, ACSL4 downregulation,), and promoted the expression of COL2A1 and inhibited the expression of MMP13. However, these changes were not observed in moderate and severe OA chondrocytes. Ferroptosis occurs in a region-specific manner and is exacerbated with the progression of human OA cartilage degeneration. Inhibition of ferroptosis might had a therapeutic effect on chondrocytes with mild OA but had no significant therapeutic effect on chondrocytes with moderate to severe OA.


Subject(s)
Cartilage, Articular , Ferroptosis , Osteoarthritis , Humans , Cartilage, Articular/metabolism , Cells, Cultured , Osteoarthritis/metabolism , Chondrocytes/metabolism
20.
J Cell Mol Med ; 27(23): 3928-3938, 2023 12.
Article in English | MEDLINE | ID: mdl-37799103

ABSTRACT

Major depressive disorder (MDD) is a severe mental disorder associated with high rates of morbidity and mortality. Current first-line pharmacotherapies for MDD are based on enhancement of monoaminergic neurotransmission, but these antidepressants are still insufficient and produce significant side-effects. Consequently, the development of novel antidepressants and therapeutic targets is desired. Engeletin, a natural Smilax glabra rhizomilax derivative, is a compound with proven efficacy in treating ischemic stroke, yet its therapeutic effects and mechanisms for depression remain unexplored. The effects of engeletin were assessed in the forced swimming test (FST) and tail suspension test (TST) in mice. Engeletin was also investigated in the chronic restraint stress (CRS) mouse model of depression with fluoxetine (FLX) as the positive control. Changes in prefrontal cortex (PFC) spine density, synaptic plasticity-linked protein expressions and the brain-derived neurotrophic factor (BDNF)-tyrosine kinase B (TrkB)- mammalian target of rapamycin complex 1 (mTORC1) signalling pathway after chronic stress and engeletin treatment were then investigated. The TrkB and mTORC1 selective inhibitors, ANA-12 and rapamycin, respectively, were utilized to assess the engeletin's antidepressive mechanisms. Our data shows that engeletin exhibited antidepressant-like activity in the FST and TST in mice without affecting locomotor activity. Furthermore, it exhibited efficiency against the depression of CRS model. Moreover, it enhanced the BDNF-TrkB-mTORC1 pathway in the PFC during CRS and altered the reduction in dendritic spine density and levels of synaptic plasticity-linked protein induced by CRS. In conclusion, engeletin has antidepressant activity via activation of the BDNF-TrkB-mTORC1 signalling pathway and upregulation of PFC synaptic plasticity.


Subject(s)
Depressive Disorder, Major , Neuronal Plasticity , Receptor, trkB , Animals , Humans , Mice , Antidepressive Agents/pharmacology , Antidepressive Agents/therapeutic use , Brain-Derived Neurotrophic Factor/drug effects , Brain-Derived Neurotrophic Factor/metabolism , Depressive Disorder, Major/drug therapy , Hippocampus/metabolism , Mammals/metabolism , Mechanistic Target of Rapamycin Complex 1/drug effects , Mechanistic Target of Rapamycin Complex 1/metabolism , Protein-Tyrosine Kinases/metabolism , Stress, Psychological/drug therapy , Stress, Psychological/metabolism , Neuronal Plasticity/drug effects , Receptor, trkB/drug effects , Receptor, trkB/metabolism
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