ABSTRACT
BACKGROUND: Danggui Shaoyao San (DSS), a frequently prescribed Chinese medicine formula, has demonstrated clinical efficacy in the treatment of Alzheimer's disease (AD). This study aims to explore the differences in therapeutic effects of DSS and its disassembled prescriptions, Suangan (SG) and Xingan (XG), in treating Alzheimer's Disease and the mechanism of DSS recovering autophagy in AD. METHODS: A network pharmacology strategy was employed to delineate the bioactive constituents, associated targets, and regulatory mechanisms of DSS in AD, encompassing in silico target forecasting, the generation and scrutiny of PPI networks, alongside GO and KEGG-based pathway elucidation. An AD mouse model, induced by intracerebroventricular injection of Aß1-42, was used to evaluate the therapeutic effects of DSS and its disassembled prescriptions on AD. Cognitive function was evaluated using the Morris water maze. Expression levels of inflammatory cytokines were quantified via RT-qPCR and ELISA. Western blotting was used to detect the expression of proteins related to AD pathological markers and the AMPK/mTOR signaling pathway. RESULTS: 50 active compounds and 718 HUB genes were screened from relevant databases and literature. KEGG and GO analyses indicated that DSS's potential mechanisms against AD involved the AMPK/mTOR signaling pathway and mitophagy. In vivo animal model, the results demonstrated that DSS, SG, and XG treatments improved cognitive function and ameliorated neuroinflammation in mice. Additionally, they alleviated the pathological changes of neuronal cells. These treatments also increased the protein level of PSD-95, and decreased levels of APP and p-Tau. Among them, DSS exhibited the best efficacy. Furthermore, DSS, SG, and XG upregulated the expression of LC3, Beclin1, and p-AMPK, while decreasing the expression of P62 and p-mTOR. CONCLUSIONS: DSS, SG, and XG were found to ameliorate AD-related pathological symptoms in Aß1-42-injected mice, likely through the AMPK/mTOR autophagy signaling pathway.
Subject(s)
Alzheimer Disease , Autophagy , Drugs, Chinese Herbal , Neuroprotective Agents , TOR Serine-Threonine Kinases , Animals , Male , Mice , Alzheimer Disease/drug therapy , AMP-Activated Protein Kinases/metabolism , Autophagy/drug effects , Disease Models, Animal , Drugs, Chinese Herbal/pharmacology , Neuroprotective Agents/pharmacology , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/metabolismABSTRACT
BACKGROUND: Major depressive disorder (MDD) is a prevalent and disabling mood disorder, thought to be linked with brain white matter (WM) alterations. Prior diffusion tensor imaging (DTI) studies have reported inconsistent changes in fractional anisotropy (FA) across different brain regions in MDD patients. However, none of these studies utilized raw t-map data for WM meta-analysis in MDD. Our study aims to address this gap by conducting a whole-brain-based meta-analysis of FA in MDD using Seed-based d mapping via permutation of subject images (SDM-PSI), combining reported peak coordinates and raw statistical parametric maps. OBJECTIVES: Following PRISMA guidelines, we performed a systematic search and meta-analysis to compare FA in MDD patients with healthy controls (HC). Our goal was to identify WM abnormalities in MDD, using SDM, which could shed light on the disorder's pathogenesis. RESULTS: The meta-analysis included 39 studies with 3696 participants (2094 with MDD, 1602HC). It revealed that MDD patients, in comparison to HC, have lower FA in the corpus callosum (CC) and anterior thalamic projections (ATP). Subgroup analyses indicated that the CC is a more stable pathogenic factor in MDD. Meta-regression analyses showed no linear correlation between the mean age, percentage of female patients, duration of depression, and FA abnormalities. This suggests that WM impairments in interhemispheric connections and anterior thalamocortical circuits are significant in the pathogenesis of MDD.
Subject(s)
Corpus Callosum , Depressive Disorder, Major , Diffusion Tensor Imaging , White Matter , Female , Humans , Male , Anisotropy , Corpus Callosum/diagnostic imaging , Corpus Callosum/pathology , Depressive Disorder, Major/diagnostic imaging , Depressive Disorder, Major/pathology , Thalamus/diagnostic imaging , Thalamus/pathology , White Matter/diagnostic imaging , White Matter/pathologyABSTRACT
The viscosity and viscoelasticity of polyelectrolyte solutions with a single electrostatic interaction have been carefully studied experimentally and theoretically. Despite some theoretical models describe experimental results well, the influence of multiple interactions (electrostatic and hydrophobic) on rheological scaling is not yet fully resolved. Herein, we systematically study the microstructures and rheological properties of short-side-chain perfluorosulfonic acid (S-PFSA), the most promising candidate of a proton exchange membrane composed of a hydrophobic backbone with hydrophilic side-chains, in water/2-propanol. Small-angle X-ray scattering confirms that semiflexible S-PFSA colloidal particles with a length of ~38 nm and a diameter of 1-1.3 nm are formed, and the concentration dependence of the correlation length (ξ) obeys the power law ξ~c-0.5 consistent with the prediction of Dobrynin et al. By combining macrorheology with diffusing wave spectroscopy microrheology, the semidilute unentangled, semidilute entangled, and concentrated regimes corresponding to the scaling relationships ηsp~c0.5, ηsp~c1.5, and ηsp~c4.1 are determined. The linear viscoelasticity indicates that the entanglement concentration (ce) obtained from the dependence of ηsp on the polymer concentration is underestimated owing to hydrophobic interaction. The true entanglement concentration (cte) is obtained by extrapolating the plateau modulus (Ge) to the terminal modulus (Gt). Furthermore, Ge and the plateau width, τr/τe (τr and τe denote reptation time and Rouse time), scale as Ge~c2.4 and τr/τe~c4.2, suggesting that S-PFSA dispersions behave like neutral polymer solutions in the concentrated regime. This work provides mechanistic insight into the rheological behavior of an S-PFSA dispersion, enabling quantitative control over the flow properties in the process of solution coating.
ABSTRACT
Alzheimer's disease (AD) is a neurodegenerative brain disorder that progressively impairs long-term and working memory. The function and mechanism of PA(Patchouli alcohol) in improving AD in the external treatment of encephalopathy remain unclear. This study aimed to investigate the therapeutic effect of PA on AD using an Aß1-42 induced AD mouse model with LPS(Lipopolysaccharide) stimulation of BV2 microglial cells. Additionally, we aimed to explore the potential mechanism of PA in enhancing autophagy and reducing neuroinflammation through the AMPK (AMP-activated protein kinase)/mTOR (Mammaliam target of rapamycin) signaling pathway. The Morris water maze was used to assess cognitive function, and cortical and hippocampal tissues were collected for further analysis of the corresponding signaling pathways and inflammatory changes through biological experiments. Our research findings demonstrate that PA has a significant positive impact on cognitive and memory impairments in mice that have been induced with Aß1-42-induced AD. Additionally, PA was also found to revert the activation of microglia induced by LPS. These effects may be attributed to the reduction of neuroinflammation and enhancement of the AMPK/mTOR autophagy pathway. Therefore, PA may serve as an effective therapeutic option to prevent or delay the progression of AD-associated memory dysfunction.
Subject(s)
AMP-Activated Protein Kinases , Alzheimer Disease , Amyloid beta-Peptides , Cognitive Dysfunction , Microglia , Peptide Fragments , Signal Transduction , TOR Serine-Threonine Kinases , Animals , Amyloid beta-Peptides/metabolism , TOR Serine-Threonine Kinases/metabolism , Mice , Alzheimer Disease/metabolism , Alzheimer Disease/drug therapy , Cognitive Dysfunction/metabolism , Cognitive Dysfunction/drug therapy , Peptide Fragments/metabolism , Peptide Fragments/toxicity , AMP-Activated Protein Kinases/metabolism , Signal Transduction/drug effects , Male , Microglia/drug effects , Microglia/metabolism , Disease Models, AnimalABSTRACT
BACKGROUND: Although the pathophysiological mechanism of septic cardiomyopathy has been continuously discovered, it is still a lack of effective treatment method. Cortistatin (CST), a neuroendocrine polypeptide of the somatostatin family, has emerged as a novel cardiovascular-protective peptide, but the specific mechanism has not been elucidated. PURPOSE: The aim of our study is to explore the role of CST in cardiomyocytes pyroptosis and myocardial injury in sepsis and whether CST inhibits cardiomyocytes pyroptosis through specific binding with somastatin receptor 2 (SSTR2) and activating AMPK/Drp1 signaling pathway. METHODS AND RESULTS: In this study, plasma CST levels were significantly high and were negatively correlated with N-terminal pro-B type natriuretic peptide (NT-proBNP), a biomarker for cardiac dysfunction, in patients with sepsis. Exogenous administration of CST significantly improved survival rate and cardiac function in mouse models of sepsis by inhibiting the activation of the NLRP3 inflammasome and pyroptosis of cardiomyocytes (decreased cleavage of caspase-1, IL-1ß and gasdermin D). Pharmacological inhibition and genetic ablation revealed that CST exerted anti-pyroptosis effects by specifically binding to somatostatin receptor subtype 2 (SSTR2), thus activating AMPK and inactivating Drp1 to inhibit mitochondrial fission in cardiomyocytes. CONCLUSIONS: This study is the first to report that CST attenuates septic cardiomyopathy by inhibiting cardiomyocyte pyroptosis through the SSTR2-AMPK-Drp1-NLRP3 pathway. Importantly, CST specifically binds to SSTR2, which promotes AMPK phosphorylation, inhibits Drp1-mediated mitochondrial fission, and reduces ROS levels, thereby inhibiting NLRP3 inflammasome activation-mediated pyroptosis and alleviating sepsis-induced myocardial injury.
Subject(s)
AMP-Activated Protein Kinases , Cardiomyopathies , Mice, Inbred C57BL , Myocytes, Cardiac , NLR Family, Pyrin Domain-Containing 3 Protein , Neuropeptides , Pyroptosis , Receptors, Somatostatin , Sepsis , Signal Transduction , Animals , Pyroptosis/drug effects , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Receptors, Somatostatin/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Humans , Sepsis/drug therapy , Signal Transduction/drug effects , AMP-Activated Protein Kinases/metabolism , Neuropeptides/metabolism , Mice , Male , Cardiomyopathies/drug therapy , Cardiomyopathies/etiology , Cardiomyopathies/metabolism , Disease Models, Animal , Mice, KnockoutABSTRACT
Background: Identification is the first step for treatment of hypertension. However, the awareness rate of hypertension was not high globally. This study aimed to examine the potential role of health insurance for early-identifying hypertension among urban older residents in China. Methods: In this cross-sectional study, urban residents aged 60+ years were chosen from Nanjing municipality of China in 2018. The outcome measure was hypertension status ("no hypertension," "diagnosed hypertension" or "un-diagnosed hypertension"). Independent variable was health insurance ("Urban Employee Basic Medical Insurance scheme, UEBMI" or "Urban Resident Basic Medical Insurance scheme, URBMI"). Logistic regression models were introduced to estimate odds ratio (OR) and 95% confidence interval (CI) to examine the association between health insurance and hypertension. Results: Totally, 19,742 participants completed the study. Among overall, URBMI and UEBMI participants, 47.2% (95%CI = 46.5, 47.9%), 38.4% (95%CI = 37.3, 39.6%) and 52.1% (95%CI = 51.2, 53.0%), separately, were diagnosed with hypertension, while the prevalence of un-diagnosed hypertension was 12.7% (95%CI = 12.2, 13.2%), 18.5% (95%CI = 17.6, 19.4%) and 9.6% (95%CI = 9.1, 10.1%), respectively. For overall participants, those with UEBMI were more likely to have hypertension identified (OR = 1.20; 95%CI = 1.11, 1.29) and at lower odds to experience un-diagnosed hypertension (OR = 0.68; 95%CI = 0.61, 0.76) compared to their counterparts with URBMI after control for potential confounders. Moreover, such associations of health insurance with diagnosed and un-diagnosed hypertension were also observed among participants stratified by age and gender. Conclusion: Favorable health insurance may be a pathway for identifying hypertension among urban older residents in China. This study has important public health implications that hypertension may be identified early through favorable health insurance policies for older residents in China.
Subject(s)
Hypertension , Insurance, Health , Urban Population , Humans , Hypertension/epidemiology , Hypertension/diagnosis , Female , China/epidemiology , Male , Cross-Sectional Studies , Aged , Middle Aged , Insurance, Health/statistics & numerical data , Urban Population/statistics & numerical data , Aged, 80 and overABSTRACT
Polymers are ideally utilized as damping materials due to the high internal friction of molecular chains, enabling effective suppression of vibrations and noises in various fields. Current strategies rely on broadening the glass transition region or introducing additional relaxation components to enhance the energy dissipation capacity of polymeric damping materials. However, it remains a significant challenge to achieve high damping efficiency through structural control while maintaining dynamic characteristics. In this work, we propose a new strategy to develop hyperbranched vitrimers (HBVs) containing dense pendant chains and loose dynamic crosslinked networks. A novel yet weak dynamic transesterification between the carboxyl and boronic acid ester was confirmed and used to prepare HBVs based on poly (hexyl methacrylate-2-(4-ethenylphenyl)-5,5-dimethyl-1,3,2-dioxaborinane) P(HMA-co-ViCL) copolymers. The A B n ${{AB}_{n}}$ -type of macromonomers, the crosslinking points formed by the dynamic covalent connection via the associative exchange, and the weak yet dynamic exchange reaction are the three keys to developing high-performance HBV damping materials. We found that P(HMA-co-ViCL) 20k-40-60â HBV exhibited ultrahigh energy-dissipation performance over a broad frequency and temperature range, attributed to the synergistic effect of dense pendant chains and weak dynamic covalent crosslinks. This unique design concept will provide a general approach to developing advanced damping materials.
ABSTRACT
Ionogels with excellent mechanical performance and conductivity have been considered as ideal candidates for flexible ionotronics. However, current ionogels suffer from the well-known trade-off between mechanical strength and conductivity. Herein, we construct an ionogel with bicontinuous phase structures, a polymer-rich phase, and a solvent-rich phase. The synergy of the polymer-rich phase as an energy dissipation mechanism and the solvent-rich phase as a conductive nanochannel enables the resultant bicontinuous ionogel to show comprehensive properties, a tensile strength of 4.2 MPa, a toughness of 14.4 MJ/m3, a conductivity of 4.3 mS/cm, excellent self-healing capability, and reprocessability. Benefiting from the remarkable mechanical performance and high conductivity, the integrated supercapacitor achieves a high specific capacitance of 118 mF/cm2 (at a current density of 0.2 mA/cm2) and a capacitance retention of up to 90% (1000 charge-discharge cycles). More significantly, the resultant supercapacitor retains outstanding electrochemical performance even after being subjected to various deformations and even under harsh conditions. This study provides a reliable strategy for developing a high-performance ionogel electrolyte and broadens its application in flexible ionotronics.
ABSTRACT
Background: The mRNA vaccine has demonstrated significant effectiveness in protecting against SARS-CoV-2 during the pandemic, including against severe forms of the disease caused by emerging variants. In this study, we examined safety, immunogenicity, and relative efficacy of a heterologous booster of the lipopolyplex (LPP)-based mRNA vaccine (SW-BIC-213) versus a homologous booster of an inactivated vaccine (BBIBP) in Laos. Methods: In this phase 3 clinical trial, which was randomized, parallel controlled and double-blinded, healthy adults aged 18 years and above were recruited from the Southern Savannakhet Provincial Hospital and Champhone District Hospital. The primary outcomes were safety and immunogenicity, with efficacy as an exploratory endpoint. Participants who were fully immunized with a two-dose inactivated vaccine for more than 6 months were assigned equally to either the SW-BIC-213 group (25 µg) or BBIBP group. The primary safety endpoint was to describe the safety profile of all participants in each group up to 6 months post-booster immunization. The primary immunogenic outcome was to demonstrate the superiority of the neutralizing antibody response, in terms of geometric mean titers (GMTs) of SW-BIC-213, compared with BBIBP 28 days after the booster dose. The exploratory efficacy endpoint aimed to assess the relative efficacy of SW-BIC-213 compared to BBIBP against virologically confirmed symptomatic COVID-19 over a 6-month period. The trial was registered with ClinicalTrials.gov (NCT05580159). Findings: Between October 10, 2022, and January 13, 2023, 1200 participants were assigned to SW-BIC-213 group and 1203 participants in the BBIBP group. All adverse reactions observed during the study were tolerable, transient, and resolved spontaneously. Solicited local reactions were the main adverse reactions in both the SW-BIC-213 group (43.8%) and BBIBP group (14.8%) (p < 0.001). Heterologous boosting with SW-BIC-213 induced higher live virus neutralizing antibodies to SARS-CoV-2 wildtype and BA.5 strains with GMTs reaching 750.1 and 192.9 than homologous boosting with BBIBP with GMTs of 131.5 (p < 0.001) and 47.5 (p < 0.001) on day 29. The statistical findings revealed that, following a period of 14-day to 6-month after booster vaccination, the SW-BIC-213 group exhibited a relative vaccine efficacy (VE) of 70.1% (95% CI: 34.2-86.4) against symptomatic COVID-19 when compared to the BBIBP group. Interpretation: A heterologous booster with the COVID-19 mRNA vaccine SW-BIC-213 manifests a favorable safety profile and proves highly immunogenic and efficacious in preventing symptomatic COVID-19 in individuals who have previously received two doses of inactivated vaccine. Funding: Shanghai Strategic Emerging Industries Development Special Fund, Biomedical Technology Support Special Project of Shanghai "Science and Technology Innovation Action Plan", Shanghai Municipal Science and Technology Commission.
ABSTRACT
Matrix vesicles (MVs) have shown strong effects in diseases such as vascular ectopic calcification and pathological calcified osteoarthritis and in wound repair of the skeletal system due to their membranous vesicle characteristics and abundant calcium and phosphorus content. However, the role of MVs in the progression of osteoporosis is poorly understood. Here, we report that annexin A5, an important component of the matrix vesicle membrane, plays a vital role in bone matrix homeostasis in the deterioration of osteoporosis. We first identified annexin A5 from adherent MVs but not dissociative MVs of osteoblasts and found that it could be sharply decreased in the bone matrix during the occurrence of osteoporosis based on ovariectomized mice. We then confirmed its potential in mediating the mineralization of the precursor osteoblast lineage via its initial binding with collagen type I to achieve MV adhesion and the subsequent activation of cellular autophagy. Finally, we proved its protective role in resisting bone loss by applying it to osteoporotic mice. Taken together, these data revealed the importance of annexin A5, originating from adherent MVs of osteoblasts, in bone matrix remodeling of osteoporosis and provided a new strategy for the treatment and intervention of bone loss.
Subject(s)
Bone Diseases, Metabolic , Osteoporosis , Vascular Calcification , Animals , Mice , Annexin A5/metabolism , Calcification, Physiologic/physiology , Bone Matrix/metabolismABSTRACT
The jamming effect is critical in processing short fiber-reinforced thermoplastics (FRTs). Fiber jamming can induce discontinuous shear thickening (DST) in simple shear and result in fiber-matrix separation in more complex flows such as injection molding and compression molding of FRTs. The confinement effect commonly induces local jams and strongly enhances fiber jamming. However, the transient evolution of local fiber jams under confinement and its correlation with the tumbling of fibers are still elusive. In this study, we adopted rheo-PIV (particle image velocity) techniques to study this effect for glass fiber-reinforced thermoplastics (FRTs). The translational and tumbling motion of fiber were determined during rheological measurements, and the distribution of fiber orientation was determined by X-ray CT. Three shear banding regions appeared after the viscosity overshoot under high shear stress in suspensions with high fiber content, which was associated with the three regions of fiber orientation across the gap due to confinement. Shear banding was ascribed to the different tumbling speeds across the gap because of the different initial orientations and different wall confinements near and far from the wall. The local shear thickening and jamming behavior became most significant under intermediate confinement, and were affected by shear strain, shear stress, and fiber contents. 3D state diagrams were constructed to show the confinement effect on the evolution of shear banding and jamming.
ABSTRACT
Microglia hyperactivation is an important cause of neuroinflammation in Alzheimer's disease (AD). Paeoniflorin (PF), ferulic acid (FA), and atractylenolide III (ATL) are potent in anti-inflammation and neuroprotection. Multiple components can act on different targets simultaneously to exert synergistic therapeutic effects and exploring the synergistic potential between compounds is an important area of research. We investigated the effects of PF, FA, and ATL, alone or in combination, on LPS-induced neuroinflammation and autophagy in BV2 microglia cells. We found that PF, FA, and ATL, alone or in combination, significantly reduced the production of inflammatory factors such as IL-6, IL-1ß, and TNF-α, especially in the PF + FA + ATL group, which performed the best. In addition, the combination of PF, FA, and ATL significantly increased the expression of autophagy-related proteins p-AMPK, p-ULK1, Beclin1, LC3, and TFEB and decreased the expression of p62. Moreover, the restoration of autophagic flux by the combination of PF, FA, and ATL was abrogated by the addition of the autophagy inhibitor Wortmannin. In conclusion, PF, FA, and ATL have a synergistic effect in reducing LPS-induced inflammatory factor release from BV2 microglia cells, and its protective effect may be through activation of the AMPK/ULK1/TFEB autophagic signaling pathway.
Subject(s)
Lipopolysaccharides , Microglia , Humans , Microglia/metabolism , Lipopolysaccharides/pharmacology , AMP-Activated Protein Kinases/metabolism , Neuroinflammatory Diseases , AutophagyABSTRACT
In neurodegenerative diseases, microglial activation and neuroinflammation are essential for the control and progression of neurodegenerative diseases. Mitigating microglium-induced inflammation is one strategy for hindering the progression of neurodegenerative diseases. Ferulic acid (FA) is an effective anti-inflammatory agent, but its potential role and regulation mechanism in neuroinflammatory reactions have not been fully studied. In this study, the neuroinflammation model was established by lipopolysaccharide (LPS), and the inhibitory effect of FA on neuroinflammation of BV2 microglia was studied. The results showed that FA significantly reduced the production and expression of reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α), leukocyte-6 (IL-6) and interleukin-1ß (IL-1ß). We further studied the mechanism of FA's regulation of LPS-induced BV2 neuroinflammation and found that FA can significantly reduce the expression of mTOR in BV2 microglia induced by LPS, and significantly increase the expression of AMPK, indicating that FA may have an anti-inflammatory effect by activating the AMPK/mTOR signaling pathway to regulate the release of inflammatory mediators (such as NLRP3, caspase-1 p20 and IL-1ß). We further added an autophagy inhibitor (3-MA) and an AMPK inhibitor (compound C, CC) for reverse verification. The results showed that FA's inhibitory effects on TNF-α, IL-6 and IL-1ß and its regulatory effect on AMPK/mTOR were destroyed by 3-MA and CC, which further indicated that FA's inhibitory effect on neuroinflammation is related to its activation of the AMPK/mTOR autophagy signaling pathway. In a word, our experimental results show that FA can inhibit LPS-induced neuroinflammation of BV2 microglia by activating the AMPK/mTOR signaling pathway, and FA may be a potential drug for treating neuroinflammatory diseases.
Subject(s)
Lipopolysaccharides , Neurodegenerative Diseases , Humans , Lipopolysaccharides/pharmacology , Microglia , AMP-Activated Protein Kinases/metabolism , Tumor Necrosis Factor-alpha/metabolism , Interleukin-6/metabolism , Neuroinflammatory Diseases , Signal Transduction , Inflammation/chemically induced , Inflammation/drug therapy , Inflammation/metabolism , TOR Serine-Threonine Kinases/metabolism , Neurodegenerative Diseases/metabolism , NF-kappa B/metabolismABSTRACT
Soft body armor greatly improves the comfort and security of the wearers. Although laminates based on high-performance fabrics have been adopted, it remains an enormous challenge to develop fabric laminates having flexibility, low bulge deformation, and ballistic protection capability simultaneously. Herein, we report a bullet-proof bicontinuous hydrogel (BH)/ultrahigh-molecular weight polyethylene fabric (UPF) composite. The presence of the BH significantly improves the impact resistance performance of the UPF, without compromising its flexibility. In specific, the multiscale energy dissipation structures composed of hydrogen bond associations in the chain scale, bicontinuous phase structures in the nanoscale, and fibers in the microscale are broken to dissipate energy. As a result, the impact energy of the bullet is greatly absorbed and the bulge height of the composites is significantly reduced in contrast to the neat UPF laminates. This study indicates that the flexible BH-UPF composites with multiscale energy dissipation structures have a promising application in soft body armor.
ABSTRACT
High performance hydrogels have essential applications in many fields such as tissue engineering and soft robot. Herein, we develop an impact resistant hydrogel composed of bicontinuous structures of polymer-hard phase and polymer-soft phase. This unique bicontinuous phase structure is formed by modulating various hydrogen bonding interactions. During loading, the polymer-hard phase is broken accompanied by the dissociation of hydrogen bonds to dissipate energy, while the polymer-soft phase distributes the load to avoid stress concentration, thus enabling the bicontinuous hydrogel to achieve excellent strength and toughness simultaneously. Furthermore, the fracture of hierarchical energy dissipation structures efficiently reduces impact strength and increases buffer time. Owing to the synergy of the bicontinuous phase structure and hierarchical energy dissipation, the resulting bicontinuous hydrogel remains intact even if it undergoes impact at a strain rate of â¼13 000 s-1. Based on these findings, it is expected that the bicontinuous hydrogel has a potential application in the field of articular cartilage repair.
Subject(s)
Cartilage, Articular , Hydrogels , Hydrogels/chemistry , Tissue Engineering , Polymers/chemistry , Hydrogen BondingABSTRACT
Background and Objectives: Job burnout is prevalent among primary care providers (PCPs) in different countries, and the factors that can alleviate burnout in these countries have been explored. However, no study has addressed the prevalence and the correlates of job burnout among Togolese PCPs. Therefore, we aimed to examine the prevalence of burnout and its association with social support and psychological capital among PCPs in Togo. Material and Methods: We conducted a cross-sectional study in Togo from 5 to 17 November 2020 among 279 PCPs of 28 peripheral care units (PCUs). Participants completed the Maslach Burnout Inventory, Job Content Questionnaire, and Psychological Capital Questionnaire. Data were analyzed using the Mann-Whitney U test, Kruskal-Wallis H test, Pearson correlation analysis, and multiple linear regression. Results: We received 279 responses, out of which 37.28% experienced a high level of emotional exhaustion (EE), 13.62% had a high level of depersonalization (DP), and 19.71% experienced low levels of personal accomplishment (PA). EE had a significant negative correlation with the supervisor's support. In contrast, self-efficacy, hope, optimism, and resilience had a significant negative correlation with DP and a significant positive correlation with PA. Furthermore, supervisors' support significantly predicted lower levels of EE. Optimism significantly predicted lower levels of DP and higher levels of PA. Conclusions: Burnout is common among Togolese PCPs, and self-efficacy, optimism, and supervisors' support significantly contribute to low levels of job burnout among Togolese PCPs. This study provided insight into intervention programs to prevent burnout among PCPs in Togo.
Subject(s)
Burnout, Professional , Pneumonia, Pneumocystis , Humans , Cross-Sectional Studies , Togo/epidemiology , Burnout, Psychological , Burnout, Professional/epidemiology , Burnout, Professional/psychology , Social Support , Surveys and Questionnaires , Primary Health CareABSTRACT
Glucose oxidase (GOx) can catalyze the oxidation of ß-D-glucose under mild conditions to directly convert biological energy into electrical energy, which has great potential for applications in the fields of enzyme biofuel cells and glucose biosensors. In enzymatic biofuel cells, GOx is often used as an anodic catalyst to improve the performance. The important role of two intimate histidine residues, His505 and His548 (PDB code 4YNU), in the GOx active center has been highlighted in the catalytic oxidation of ß-D-glucose, but there is still a lack of systematic examination on the influence of different protonated states of His505 and His548 on the catalytic oxidation of ß-D-glucose in GOx. Therefore, in the present work, the GOx active center under the possible protonated states of His548 and His505 is systematically examined by using ONIOM calculations, as well as the influence of remote Arg210 is considered. The calculations reveal that the intimate His505 and His548 can modulate the interaction of the ß-D-glucose substrate with isoalloxazine and then control the deprotonization of the hydroxyl group bound to the anomeric carbon of ß-D-glucose like controllers. The remote Arg210 provides the driving force for the transfer of two electrons from ß-D-glucose to isoalloxazine of FAD via the long-range electrostatic attraction like a horse. Specially, the protonated His505 can serve as a good helper of Arg210 to promote the occurring of the two-proton-coupled two-electron transfer from ß-D-glucose to isoalloxazine and His548 in the active center of GOx. These findings provide much insight into the catalytic reactions of GOx in a low pH environment, which may be beneficial to expand the applications of GOx.
Subject(s)
Bioelectric Energy Sources , Glucose Oxidase , Horses , Animals , Glucose Oxidase/chemistry , Histidine , Electrodes , Glucose/chemistryABSTRACT
Identifying brain abnormalities in autism spectrum disorder (ASD) is critical for early diagnosis and intervention. To explore brain differences in ASD and typical development (TD) individuals by detecting structural features using T1-weighted magnetic resonance imaging (MRI), we developed a deep learning-based approach, three-dimensional (3D)-ResNet with inception (I-ResNet), to identify participants with ASD and TD and propose a gradient-based backtracking method to pinpoint image areas that I-ResNet uses more heavily for classification. The proposed method was implemented in a preschool dataset with 110 participants and a public autism brain imaging data exchange (ABIDE) dataset with 1099 participants. An extra epilepsy dataset with 200 participants with clear degeneration in the parahippocampal area was applied as a verification and an extension. Among the datasets, we detected nine brain areas that differed significantly between ASD and TD. From the ROC in PASD and ABIDE, the sensitivity was 0.88 and 0.86, specificity was 0.75 and 0.62, and area under the curve was 0.787 and 0.856. In a word, I-ResNet with gradient-based backtracking could identify brain differences between ASD and TD. This study provides an alternative computer-aided technique for helping physicians to diagnose and screen children with an potential risk of ASD with deep learning model.
Subject(s)
Autism Spectrum Disorder/diagnostic imaging , Brain/diagnostic imaging , Deep Learning , Adolescent , Autism Spectrum Disorder/pathology , Brain/pathology , Brain Mapping/methods , Case-Control Studies , Child , Child, Preschool , Datasets as Topic , Humans , Imaging, Three-Dimensional , Magnetic Resonance Imaging/methodsABSTRACT
Lipid rafts play important roles in signal transduction, particularly in responses to inflammatory processes. The current study aimed to identify whether lipid raft-mediated inflammation contributes to hyperhomocysteinemia (HHcy)-accelerated atherosclerosis (AS), and to investigate the underlying mechanisms. THP-1-derived macrophages were used for in vitro experiments. ApoE-/- mice were fed a high-fat diet for 12 weeks to establish an AS model, and a high-fat plus high-methionine diet was used to induce HHcy. We found that homocysteine (Hcy) increased the expression of p22phox and p67phox and promoted their recruitment into lipid rafts (indicating the assembly of the NOX complex), thereby increasing ROS generation and NOX activity, NLRP3 inflammasome activation, and pyroptosis. Mechanistically, Hcy activated the NOX-ROS-NLRP3 inflammasome pathway and induced pyroptosis by increasing the expression of acid sphingomyelinase (ASM) to promote the formation of lipid raft clustering. Importantly, lipid raft-mediated pyroptosis was confirmed in HHcy mice, and HHcy-promoted macrophage recruitment in atherosclerotic lesions and HHcy-aggravated AS were blocked by the lipid raft disruptor methyl-ß-cyclodextrin. The study findings indicate that Hcy promotes lipid raft clustering via the upregulation of ASM, which mediates the assembly of the NOX complex, causing an increase in ROS generation, NLRP3 inflammasome activation, and pyroptosis, and contributes to HHcy-induced AS.
Subject(s)
Atherosclerosis , Hyperhomocysteinemia , Animals , Apolipoproteins E , Atherosclerosis/metabolism , Hyperhomocysteinemia/metabolism , Inflammasomes/metabolism , Membrane Microdomains/metabolism , Mice , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Pyroptosis , Reactive Oxygen Species/metabolismABSTRACT
Using halo effect as the underlying theory, we examined how perceived quality of medical care influenced components of post-visit destination image (infrastructure, attraction, value for money, and enjoyment) and how each component influenced Bangladeshi outbound medical tourists' revisit intentions. Additionally, we examined how these relationships varied based on their length of stay (LOS) and travel-group size (TGS). Results showed a significant positive effect of the perceived quality of medical care on all four components of the post-visit destination image. Except for enjoyment, all three components had a significant positive influence on revisit intentions. All the proposed relationships were supported for medical tourists with higher LOS and TGS. However, for medical tourists with low LOS, the perceived quality of medical care did not influence value for money. Furthermore, value for money and enjoyment did not significantly influence revisit intentions for medical tourists with low LOS and TGS.