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1.
Environ Pollut ; 362: 124938, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39265766

RESUMO

At present, priority pollutants in printing and dyeing wastewater have attracted increasing attention, but their types and limits in the wastewater discharge standards for China's dyeing and finishing industry are still lacking. This study selected 9 printing and dyeing enterprises in a region of Zhejiang Province as the research objects. Through literature collection, field investigations, and chemical analysis, combined with industry priority pollutant screening technology, 103 and 21 characteristic pollutants were selected as preliminary and supplementary lists of priority pollutants, respectively. The results of the pollutant category analysis revealed that 55% of the pollutants on the preliminary list included carcinogens, and 29% of the pollutants on the supplementary list included alcohols. According to the four rules for in-depth screening, a total of 23 indicators (excluding those in GB 4287-2012 and its revised versions) were selected as the final list of priority pollutants, most of which were polycyclic aromatic hydrocarbons (PAHs) but also included a small number of lipid substances, such as bis (2-ethylhexyl) phthalate. The screening of these indicators not only provides data support for the expansion of water pollution control indicators and the determination of their limits in China's printing and dyeing industry, but also promotes the supplementation and improvement of the sewage discharge standard system in related industries.

2.
Adv Mater ; 36(36): e2309572, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39096076

RESUMO

The construction of ultrathin porous membranes with stable structures is critical for achieving efficient gas separation. Inspired by the binary-cooperative structural features of bones and teeth-composed of rigid hydroxyapatite and flexible collagen, which confer excellent mechanical strength-a binary-cooperative porous membrane constructed with gel-state zeolitic imidazolate frameworks (g-ZIFs), synthesized using a metal-gel-induced strategy, is proposed. The enlarged cavity size and flexible frameworks of the g-ZIF nanoparticles significantly improve gas adsorption and diffusion, respectively. After thermal treatment, the coordination structures forming rigid segments in the g-ZIF membranes appear at the stacked g-ZIF boundaries, exhibiting a higher Young's modulus than the g-ZIF nanoparticles, denoted as the flexible segments. The g-ZIF membranes demonstrate excellent tensile and compression resistances, attributed to the effective translation of binary-cooperative effects of rigidity and flexibility into the membranes. The resulting dual-aperture structure, composed of g-ZIF nanoparticles surrounded by nanoscale apertures at the boundaries, yields a membrane with a stable CO2 permeance of 4834 GPU and CO2/CH4 selectivity of 90 within 3.0 MPa.

3.
ISA Trans ; : 1-11, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39164133

RESUMO

In this paper, an event-triggered adaptive neural prescribed performance admittance control (ETANPPAC) scheme is proposed to control the constrained robotic systems without velocity sensors. To ensure compliance during human-robot interaction, the reference trajectory is obtained by reshaping the desired trajectory for the robotic systems based on the admittance relationship, where a saturation function is used to constrain the reference trajectory, avoiding excessive contact forces that could render the trajectory inexecutable. Moreover, a barrier Lyapunov function is used to constrain the tracking errors for prescribed performance, where a velocity observer and a radial basis function neural network are designed to estimate the velocity and the uncertainty of the robotic systems, respectively, to enhance control performance. To reduce the communication burden, an event-triggered mechanism is introduced and the Zeno behavior is avoided with the event-triggered condition. The stability of the whole control scheme is analyzed by the Lyapunov function. Simulation and experimental tests demonstrate that the proposed ETANPPAC scheme can track the desired trajectory well under constraints and reduce the communication burden, thereby achieving better efficiency for controlling the robotic systems compared with similar control schemes.

4.
Polymers (Basel) ; 16(15)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39125255

RESUMO

Ammonium polyphosphate (APP) and self-made nickel phytate (PANi) were used as modified materials to prepare green biomass rigid polyurethane foam (RPUF). The flame retardancy, thermal stability, smoke toxicity and mechanical properties of the modified RPUF were investigated by limiting oxygen index (LOI), a cone calorimetry (CONE) test, thermogravimetric analysis and a compression test. The results showed that the RPUF with 10 wt% APP (PANi/APP10) had the highest LOI of 26.5%. Its peak heat release rate (PHRR) and total heat release (THR) were reduced by 29.64% and 24.05% compared with PANi/APP0 without APP. And its smoke production rate (SPR) and total smoke release (TSR) decreased by 33.14% and 19.88%, respectively. Compared with pure RPUF, the compressive strength of PANi/APP10 was increased by 50%, mainly because APP itself was an ultra-fine powder, which was better compatible with the matrix and improved the hardness of the material. The results showed that the synergistic effect of the gas phase and the condensed phase mechanism could effectively improve the flame-retardant effect. The current research results provided a new strategy for the preparation of green and low-toxicity RPUF.

5.
Curr Med Sci ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145837

RESUMO

OBJECTIVE: Glioma is a central nervous system tumor arising from glial cells. Despite significant advances in diagnosis and treatment, most patients with high-grade gliomas have a poor prognosis. Many studies have shown that long noncoding RNAs (lncRNAs) may play important roles in the development, progression and treatment of many tumors, including gliomas. Molecularly targeted therapy may be a new direction for the adjuvant treatment of glioma. Therefore, we hope that by studying differentially expressed lncRNAs (DElncRNAs) in glioma, we can discover lncRNAs that can serve as biomarkers for glioma and provide better therapeutic modalities for glioma patients. METHODS: First, the expression of lncRNAs in 5 normal brain (NB) tissues and 10 glioma tissues was examined by RNA sequencing (RNA-seq). Next, we performed Kaplan-Meier analysis of data from The Cancer Genome Atlas (TCGA) database to assess the prognostic value of these variables. Finally, functional analysis of the DElncRNAs was performed by means of Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. RESULTS: RNA sequencing analysis revealed 85 upregulated miRNAs and 71 downregulated lncRNAs in low-grade glioma (LGG) and 50 upregulated lncRNAs and 70 downregulated lncRNAs in glioblastoma (GBM). Among them, AL355974.3 was the most upregulated lncRNA. LINC00632 was the most downregulated lncRNA. Second, LGG patients with higher AL355974.3 expression had worse overall survival according to Kaplan-Meier analysis of the TCGA database. Finally, bioinformatics analysis revealed that the target genes of these DElncRNAs were enriched in various biological processes and signaling pathways, such as cell metabolic and developmental processes. CONCLUSION: Our findings provide evidence that AL355974.3 may be a new biomarker for glioma.

6.
BJOG ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075929

RESUMO

OBJECTIVE: Pregnancy complicated with type B aortic dissection is a rare but devastating condition. Guidelines for managing this condition are lacking. We present our observation and experiences in managing five pregnant women with complicated type B aortic dissection in the second or third trimesters, aiming to gain insights that can aid in proposing an appropriate management strategy. DESIGN: A retrospective study. SETTING: Zhongnan Hospital of Wuhan University. POPULATION: Pregnant women with complicated type B aortic dissection. METHODS: Clinical data of five pregnant women with complicated type B aortic dissection admitted to Zhongnan Hospital of Wuhan University from January 2022 to June 2023 were collected. The clinical characteristics, treatment strategies, and corresponding maternal and infant outcomes were retrospectively analysed. MAIN OUTCOME MEASURES: Survival of mothers and foetuses. RESULTS: All five study participants were diagnosed with complicated type B aortic dissection by computed tomography angiography (CTA). The range of gestational weeks at admission was 27 weeks + 3 days to 36 weeks + 6 days. The first patient, planning a caesarean section (C-section) followed by thoracic endovascular aortic repair (TEVAR), died of aortic dissection rupture during C-section. Her neonate was successfully rescued. In contrast, the remaining four patients who underwent TEVAR first survived. Among them, three patients underwent single-stage aortic repair and delivery, while one patient received C-section 31 days after TEVAR. Three preterm live births were recorded among these surviving mothers. Neonatal death occurred in one case with a gestational age of 29 weeks + 5 days, who had foetal distress before surgery. During the follow-up period of up to 3 months, no maternal or infant death occurred. No device-related or systemic complications were observed in the surviving mothers after discharge. Routine physical examinations of the four live births showed no abnormalities. CONCLUSIONS: For pregnant women with thoracic back pain and high suspicion of aortic dissection, CTA should be conducted promptly to prevent missed or delayed diagnosis. Maternal survival should be prioritised over foetal outcome once diagnosed. TEVAR was demonstrated to be safe and feasible for such patients. For women with complicated type B aortic dissection in late pregnancy, TEVAR followed by C-section may be a promising treatment strategy.

7.
Sci Rep ; 14(1): 16651, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030238

RESUMO

A bio-based flame retardant nickel phytate (PA-Ni) was synthesized and combined with soybean oil-based polyol (SO) to create a green rigid polyurethane foam (RPUF) with enhanced compressive strength, good thermal stability and flame retardant. The results showed that the RPUF-SO2/Ni3 with 3 wt% PA-Ni had the highest initial and termination temperature, maximum thermal decomposition rate temperature and carbon residue, and better thermal stability. Its limiting oxygen index was increased by 2.6% compared with RPUF-SO2 without PA-Ni added, and the peak heat release rate (PHRR) and total heat release rate (THR) were reduced by 14.92% and 19.92%, respectively. In addition, RPUF-SO2/Ni3 had the lowest Ds under the conditions of flame (18.90) and flameless (22.41), and had the best smoke suppression effect. And the compressive strength of RPUF-SO/Ni3 was significantly enhanced by the addition of PA-Ni. The results show that the improvement of flame retardancy of RPUF is mainly the result of the combined effect of gas-phase and condensed-phase flame retardancy, among which the flame retardancy of RPUF-SO/Ni3 was the best. The current findings offer a practical way to produce green and low-carbon RPUF as well as promising prospects for the material's safe application.

8.
IEEE J Biomed Health Inform ; 28(9): 5335-5346, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38861440

RESUMO

Negative emotional states, such as anxiety and depression, pose significant challenges in contemporary society, often stemming from the stress encountered in daily activities. Stress (state or level) recognition is a crucial prerequisite for effective stress management and intervention. Presently, wearable devices have been employed to capture physiological signals and analyze stress states. However, their constant skin contact can lead to discomfort and disturbance during prolonged monitoring. In this paper, a peak attention-based multitasking framework is presented for non-contact stress recognition. The framework extracts rPPG signals from RGB facial videos, utilizing them as inputs for a novel multi-task attentional convolutional neural network for stress recognition (MTASR). It incorporates peak detection and HR estimation as auxiliary tasks to facilitate stress recognition. By leveraging multi-task learning, MTASR can utilize information related to stress physiological responses, thereby enhancing feature extraction efficiency. For stress recognition, two binary classification tasks are applied: stress state recognition and stress level recognition. The model is validated on the UBFC-Phys public dataset and demonstrates an accuracy of 94.33% for stress state recognition and 83.83% for stress level recognition. The proposed method outperforms the dataset's baseline methods and other competing approaches.


Assuntos
Face , Estresse Psicológico , Gravação em Vídeo , Humanos , Estresse Psicológico/fisiopatologia , Gravação em Vídeo/métodos , Face/fisiologia , Redes Neurais de Computação , Adulto , Masculino , Feminino , Algoritmos , Aprendizado de Máquina , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
9.
J Environ Manage ; 363: 121387, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850914

RESUMO

The persistence of dissolved organic matter (DOM) plays a crucial role in the cycling and distribution of carbon and nutrients. Nonetheless, our understanding of how environmental alterations affect the persistence of sedimentary DOM remains incomplete. Excitation Emission Fluorescence Matrix-Parallel Factor Analysis (EEM-PARAFAC) was used to examine the fluorescence and compositional characteristics of hydrophilic and hydrophobic DOM (separated using XAD-8 resin) within sediments from twelve lakes and reservoirs. Fluorescence analysis indicated that DOM persistence is dependent on the proportions of the three components derived from PARAFAC. The Mantel test showed that climatic factors had the most significant impact on DOM persistence (Mantel's r = 0.46-0.54, Mantel's p = 0.001-0.007), while anthropogenic (Mantel's r = 0.24-0.32, Mantel's p = 0.03-0.05) and hydrological factors (Mantel's r = 0.03-0.22, Mantel's p = 0.06-0.40) had a somewhat lesser influence. Environmental changes resulted in a consistent decline in DOM persistence from Northeast to Southwest China, accompanied by an increase in gross primary productivity (GPP). Reduced DOM persistence due to climate, hydrological, and anthropogenic factors may lead to elevated concentrations of total phosphorus (TP), contributing to deteriorating water quality and events such as algal blooms. The decline in water quality due to reduced DOM persistence in lakes with high GPP can exacerbate the transition from carbon sinks to carbon sources. Consequently, the persistence of sedimentary DOM significantly influences nutrient and carbon cycling in lakes. Investigating DOM persistence in lakes across diverse geographic locations offers a new perspective on lake eutrophication and carbon emissions. Furthermore, it is crucial to develop targeted recommendations for lake restoration and management.


Assuntos
Ciclo do Carbono , Sedimentos Geológicos , Lagos , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Lagos/química , Carbono/análise , Fósforo/análise , China , Monitoramento Ambiental
10.
Small ; : e2403879, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38881274

RESUMO

Ocean energy harvesting based on a triboelectric nanogenerator (TENG) has great application potential, while the encapsulation of triboelectric devices in water poses a critical issue. Herein, a triboelectric-electromagnetic hybrid nanogenerator (TE-HNG) consisting of TENGs and electromagnetic generators (EMGs) is proposed to harvest water flow energy. A magnetic coupling transmission component is applied to replace traditional bearing structures, which can realize the fully enclosed packaging of the TENG devices and achieve long-lasting energy harvesting from water flow. Under the intense water impact, magnetic coupling reduces the possibility of internal gear damage due to excessive torque, indicating superior stability and robustness compared to conventional TENG. At the waterwheel rotates speed of 75 rpm, the TE-HNG can generate an output peak power of 114.83 mW, corresponding to a peak power density of 37.105 W m-3. After 5 h of continuous operation, the electrical output attenuation of TENG is less than 3%, demonstrating excellent device durability. Moreover, a self-powered temperature sensing system and a self-powered cathodic protection system based on the TE-HNG are developed and illustrated. This work provides a prospective strategy for improving the output stability of TENGs, which benefits the practical applications of the TENGs in large-scale blue energy harvesting.

11.
Int Immunopharmacol ; 137: 112427, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38889506

RESUMO

The hematopoietic homeostasis in the bone marrow is inextricably intertwined with the immune milieu in peripheral circulation. Researches investigating the pathogenesis of systemic lupus erythematosus (SLE) have defined considerable secretion of inflammatory mediators and activation of pro-inflammatory cells. However, the impacts of "extrinsic" factors on hematopoietic stem and progenitor cells (HSPCs) remain unclear, and it is uncertain whether treatments can help coordinate the biased differentiation. In this study, we showed differences in the proportions of common myeloid progenitors (CMP) and myeloid output in the bone marrow of premorbid and morbid MRL/lpr mice using flow cytometry. RNA-seq analysis of lineage-affiliated transcriptional factors and dysregulated genes within lin- HSPCs revealed inflammation potentiation during disease progression. Further, intra-bone marrow mesenchymal stem cells transplantation (IBM-MSCT) partially coordinated myeloid generation and counteracted lupus-associated inflammation gene alterations, compared to intravenous injection. Additionally, co-culturing with umbilical cord mesenchymal stem cells (UC-MSCs) intervened in myeloid lineage tendency, as detected by RT-qPCR of myeloid-related genes. Our research demonstrated enhanced tendency toward myeloid differentiation and highlighted the feasibility of IBM-MSCT for lineage-biased HSPCs in MRL/lpr lupus model, providing novel insight into hematopoiesis and MSC-related treatments for SLE.


Assuntos
Células-Tronco Hematopoéticas , Lúpus Eritematoso Sistêmico , Transplante de Células-Tronco Mesenquimais , Camundongos Endogâmicos MRL lpr , Animais , Lúpus Eritematoso Sistêmico/terapia , Camundongos , Células-Tronco Hematopoéticas/metabolismo , Feminino , Células-Tronco Mesenquimais , Modelos Animais de Doenças , Diferenciação Celular , Células Mieloides/imunologia , Células Cultivadas , Humanos
12.
World J Stem Cells ; 16(3): 267-286, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38577236

RESUMO

BACKGROUND: The bone remodeling during orthodontic treatment for malocclusion often requires a long duration of around two to three years, which also may lead to some complications such as alveolar bone resorption or tooth root resorption. Low-intensity pulsed ultrasound (LIPUS), a noninvasive physical therapy, has been shown to promote bone fracture healing. It is also reported that LIPUS could reduce the duration of orthodontic treatment; however, how LIPUS regulates the bone metabolism during the orthodontic treatment process is still unclear. AIM: To investigate the effects of LIPUS on bone remodeling in an orthodontic tooth movement (OTM) model and explore the underlying mechanisms. METHODS: A rat model of OTM was established, and alveolar bone remodeling and tooth movement rate were evaluated via micro-computed tomography and staining of tissue sections. In vitro, human bone marrow mesenchymal stem cells (hBMSCs) were isolated to detect their osteogenic differentiation potential under compression and LIPUS stimulation by quantitative reverse transcription-polymerase chain reaction, Western blot, alkaline phosphatase (ALP) staining, and Alizarin red staining. The expression of Yes-associated protein (YAP1), the actin cytoskeleton, and the Lamin A/C nucleoskeleton were detected with or without YAP1 small interfering RNA (siRNA) application via immunofluorescence. RESULTS: The force treatment inhibited the osteogenic differentiation potential of hBMSCs; moreover, the expression of osteogenesis markers, such as type 1 collagen (COL1), runt-related transcription factor 2, ALP, and osteocalcin (OCN), decreased. LIPUS could rescue the osteogenic differentiation of hBMSCs with increased expression of osteogenic marker inhibited by force. Mechanically, the expression of LaminA/C, F-actin, and YAP1 was downregulated after force treatment, which could be rescued by LIPUS. Moreover, the osteogenic differentiation of hBMSCs increased by LIPUS could be attenuated by YAP siRNA treatment. Consistently, LIPUS increased alveolar bone density and decreased vertical bone absorption in vivo. The decreased expression of COL1, OCN, and YAP1 on the compression side of the alveolar bone was partially rescued by LIPUS. CONCLUSION: LIPUS can accelerate tooth movement and reduce alveolar bone resorption by modulating the cytoskeleton-Lamin A/C-YAP axis, which may be a promising strategy to reduce the orthodontic treatment process.

13.
Cell Prolif ; 57(8): e13640, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38556840

RESUMO

Macrophages play a pivotal role in the immunological cascade activated in response to biomedical implants, which predetermine acceptance or rejection of implants by the host via pro- and anti-inflammatory polarisation states. The role of chemical signals in macrophage polarisation is well-established, but how physical cues regulate macrophage function that may play a fundamental role in implant-bone interface, remains poorly understood. Here we find that bone marrow-derived macrophages (BMDM) cultured on polyacrylamide gels of varying stiffness exhibit different polarisation states. BMDM are 'primed' to a pro-inflammatory M1 phenotype on stiff substrates, while to an anti-inflammatory M2 phenotype on soft and medium stiffness substrates. It is further observed that matrix stiffening increases Piezo1 expression, as well as leads to subsequent activation of the mechanotransduction signalling effector YAP, thus favouring M1 polarisation whilst suppressing M2 polarisation. Moreover, upon treatment with YAP inhibitor, we successfully induce macrophage re-polarisation to the M2 state within the implant site microenvironment, which in turn promotes implant osseointegration. Collectively, our present study thus characterises the critical role of the Piezo1-YAP signalling axis in macrophage mechanosensing and stiffness-mediated macrophage polarisation and provides cues for the design of immuno-modulatory biomaterials that can regulate the macrophage phenotype.


Assuntos
Canais Iônicos , Macrófagos , Mecanotransdução Celular , Transdução de Sinais , Proteínas de Sinalização YAP , Macrófagos/metabolismo , Animais , Camundongos , Canais Iônicos/metabolismo , Proteínas de Sinalização YAP/metabolismo , Camundongos Endogâmicos C57BL , Polaridade Celular/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células Cultivadas , Matriz Extracelular/metabolismo , Resinas Acrílicas/química , Resinas Acrílicas/farmacologia , Proteínas de Ciclo Celular/metabolismo , Osseointegração/efeitos dos fármacos
14.
Anal Chem ; 96(17): 6523-6527, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38634570

RESUMO

Complete sample digestion is a prerequisite for acquiring high-quality analytical results for geological samples. Closed-vessel acid digestion (bomb) has typically been used for the total digestion of refractory geological samples. However, the long digestion time (4-5 days) and insoluble fluoride complexes still pose challenges for digesting refractory geological samples using this approach. In this study, an efficient and simplified digestion technique combining ultrafine powders from planetary ball milling with bomb digestion was developed for trace element analysis of refractory geological samples: peridotite and granitoid. The method shows two significant improvements compared with previous approaches. (1) By performing dry planetary ultrafine milling, the initial 200 mesh peridotite (<74 µm) could be reduced to 800 mesh (<20 µm) in 6 min at a ball-to-powder mass ratio of approximately 15 using 3 mm tungsten carbide milling balls. (2) Complete peridotite and granitoid dissolution were achieved in approximately 2 h, 60 times faster than what is achievable using previous methods (2 h vs 120 h). Moreover, ultrafine powders effectively suppressed insoluble fluoride formation during bomb digestion. A suite of peridotite and granitoid reference materials were measured to evaluate the stability of this method. This efficient, simple, and reliable sample digestion method could benefit geological, food, environmental, and other fields requiring solid sample decomposition via wet acid, fusion, combustion, or dry ashing.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38668842

RESUMO

The ammonia fiber expansion (AFEX) pretreatment of lignocellulosic biomass offers a significant advantage in terms of obtaining high glucan conversion, with the added benefit of ammonia being fully recyclable. However, despite the high efficiency of AFEX in pretreating lignocellulose, relatively high enzyme loading is still required for effective cellulose conversions. In this study, we have updated the AFEX pretreatment method; ammonia and sodium sulfite (ASS) can be used to produce a more digestible substrate. The results demonstrate that ASS-pretreated corn stover (CS) yields a higher fermentable sugar yield compared with AFEX pretreatment, even at lower enzyme loadings. Specifically, at an enzyme loading of 12 mg protein/g glucan, ASS-CS achieved 88.8% glucose and 80.6% xylose yield. Characterization analysis reveals that lignin underwent sulfonation during ASS pretreatment. This modification results in a more negative zeta potential for ASS-CS, indicating a reduction in nonproductive adsorption between lignin and cellulase through increased electrostatic repulsion.

16.
Brain Behav Immun ; 119: 56-83, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38555992

RESUMO

Decreased hippocampal tropomyosin receptor kinase B (TrkB) level is implicated in the pathophysiology of stress-induced mood disorder and cognitive decline. However, how TrkB is modified and mediates behavioral responses to chronic stress remains largely unknown. Here the effects and mechanisms of TrkB cleavage by asparagine endopeptidase (AEP) were examined on a preclinical murine model of chronic restraint stress (CRS)-induced depression. CRS activated IL-1ß-C/EBPß-AEP pathway in mice hippocampus, accompanied by elevated TrkB 1-486 fragment generated by AEP. Specifi.c overexpression or suppression of AEP-TrkB axis in hippocampal CaMKIIα-positive cells aggravated or relieved depressive-like behaviors, respectively. Mechanistically, in addition to facilitating AMPARs internalization, TrkB 1-486 interacted with peroxisome proliferator-activated receptor-δ (PPAR-δ) and sequestered it in cytoplasm, repressing PPAR-δ-mediated transactivation and mitochondrial function. Moreover, co-administration of 7,8-dihydroxyflavone and a peptide disrupting the binding of TrkB 1-486 with PPAR-δ attenuated depression-like symptoms not only in CRS animals, but also in Alzheimer's disease and aged mice. These findings reveal a novel role for TrkB cleavage in promoting depressive-like phenotype.


Assuntos
Depressão , Hipocampo , Estresse Psicológico , Animais , Hipocampo/metabolismo , Camundongos , Depressão/metabolismo , Masculino , Estresse Psicológico/metabolismo , Receptor trkB/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Comportamento Animal/fisiologia , Transdução de Sinais/fisiologia , Doença de Alzheimer/metabolismo , Glicoproteínas de Membrana/metabolismo
17.
Sci Total Environ ; 918: 170625, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38320705

RESUMO

Intensive anthropogenic activities, such as excessive nitrogen input and dam construction, have altered the nitrogen cycle in the global river system. However, the focus on the source, transformation and fate of nitrogen in the Yellow River is still scarce. In this study, the multiple isotopes (δ15N-NO3-, δ18O-NO3-, δ15N-NH4+ and δ15N-PN) were deciphered to explore the nitrogen cycling processes and the driving factors in the thermally stratified cascade reservoirs (Sanmenxia Reservoir: SMXR and Xiaolangdi Reservoir: XLDR) and Lower Yellow River (LYR) during the drainage period of the XLDR. In the SMXR, algal bloom triggered the assimilation process in the upper layer before the SMX Dam, followed by remineralization and subsequent nitrification processes in the lower water layers. The nitrification reaction in the XLDR progressively increased along both longitudinal and vertical directions to the lower layer of the XLD Dam, which was linked to the variation in the water residence time of riverine, transition and lentic zones. The robust nitrification rates in the lower layer of the lentic zone coincided with the substantial depletion of nitrate isotopic composition and enrichment of both δ15N-PN and δ15N-NH4+, indicating the longer water residence time not only promoted the growth of the nitrifying population but also facilitated the remineralization to enhance NH4+ availability. In the LYR, the slight nitrate assimilation, as indicated by nitrate isotopic composition and fractionation models, was the predominant nitrogen transformation process. The Bayesian isotope mixing model results showed that manure and sewage was the dominant nitrate source (50 %) in the middle and lower Yellow River. Notably, the in-reservoir nitrification was a significant nitrate source (27 %) in the XLDR and LYR. Our study deepens the understanding of anthropogenic activities impacting the nitrogen cycle in the river-reservoir system, providing valuable insight into water quality management and nitrogen cycle mechanisms in the Yellow River.

18.
PLoS Pathog ; 20(1): e1011729, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38206983

RESUMO

Both constitutive and inducible immune mechanisms are employed by hosts for defense against infection. Constitutive immunity allows for a faster response, but it comes with an associated cost that is always present. This trade-off between speed and fitness costs leads to the theoretical prediction that constitutive immunity will be favored where parasite exposure is frequent. We selected populations of Drosophila melanogaster under high parasite pressure from the parasitoid wasp Leptopilina boulardi. With RNA sequencing, we found the evolution of resistance in these populations was associated with them developing constitutively active humoral immunity, mediated by the larval fat body. Furthermore, these evolved populations were also able to induce gene expression in response to infection to a greater level, which indicates an overall more activated humoral immune response to parasitization. The anti-parasitoid immune response also relies on the JAK/STAT signaling pathway being activated in muscles following infection, and this induced response was only seen in populations that had evolved under high parasite pressure. We found that the cytokine Upd3, which induces this JAK/STAT response, is being expressed by immature lamellocytes. Furthermore, these immune cells became constitutively present when populations evolved resistance, potentially explaining why they gained the ability to activate JAK/STAT signaling. Thus, under intense parasitism, populations evolved resistance by increasing both constitutive and induced immune defenses, and there is likely an interplay between these two forms of immunity.


Assuntos
Parasitos , Vespas , Animais , Drosophila/genética , Drosophila melanogaster , Interações Hospedeiro-Parasita/genética , Vespas/genética
19.
IEEE Trans Med Imaging ; 43(2): 807-819, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37788194

RESUMO

Medical professionals rely on surgical video retrieval to discover relevant content within large numbers of videos for surgical education and knowledge transfer. However, the existing retrieval techniques often fail to obtain user-expected results since they ignore valuable semantics in surgical videos. The incorporation of rich semantics into video retrieval is challenging in terms of the hierarchical relationship modeling and coordination between coarse- and fine-grained semantics. To address these issues, this paper proposes a novel semantic-preserving surgical video retrieval (SPSVR) framework, which incorporates surgical phase and behavior semantics using a dual-level hashing module to capture their hierarchical relationship. This module preserves the semantics in binary hash codes by transforming the phase and behavior similarities into high- and low-level similarities in a shared Hamming space. The binary codes are optimized by performing a reconstruction task, a high-level similarity preservation task, and a low-level similarity preservation task, using a coordinated optimization strategy for efficient learning. A self-supervised learning scheme is adopted to capture behavior semantics from video clips so that the indexing of behaviors is unencumbered by fine-grained annotation and recognition. Experiments on four surgical video datasets for two different disciplines demonstrate the robust performance of the proposed framework. In addition, the results of the clinical validation experiments indicate the ability of the proposed method to retrieve the results expected by surgeons. The code can be found at https://github.com/trigger26/SPSVR.


Assuntos
Semântica , Cirurgiões , Humanos
20.
Adv Mater ; 36(8): e2306292, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37723937

RESUMO

Nanozymes, as one of the most efficient reactive oxygen species (ROS)-scavenging biomaterials, are receiving wide attention in promoting diabetic wound healing. Despite recent attempts at improving the catalytic efficiency of Pt-based nanozymes (e.g., PtCu, one of the best systems), they still display quite limited ROS scavenging capacity and ROS-dependent antibacterial effects on bacteria or immunocytes, which leads to uncontrolled and poor diabetic wound healing. Hence, a new class of multifunctional PtCuTe nanosheets with excellent catalytic, ROS-independent antibacterial, proangiogenic, anti-inflammatory, and immuno-modulatory properties for boosting the diabetic wound healing, is reported. The PtCuTe nanosheets show stronger ROS scavenging capacity and better antibacterial effects than PtCu. It is also revealed that the PtCuTe can enhance vascular tube formation, stimulate macrophage polarization toward the M2 phenotype and improve fibroblast mobility, outperforming conventional PtCu. Moreover, PtCuTe promotes crosstalk between different cell types to form a positive feedback loop. Consequently, PtCuTe stimulates a proregenerative environment with relevant cell populations to ensure normal tissue repair. Utilizing a diabetic mouse model, it is demonstrated that PtCuTe significantly facilitated the regeneration of highly vascularized skin, with the percentage of wound closure being over 90% on the 8th day, which is the best among the reported comparable multifunctional biomaterials.


Assuntos
Diabetes Mellitus , Cicatrização , Animais , Camundongos , Espécies Reativas de Oxigênio , Pele , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Materiais Biocompatíveis/farmacologia , Hidrogéis
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