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1.
Angew Chem Int Ed Engl ; : e202408359, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106109

RESUMO

Direct aromatization of cyclohexanones to synthesize substituted phenols represents a significant challenge in modern synthetic chemistry. Herein, we describe a novel ene-reductase (TsER) catalytic system that converts substituted cyclohexanones into the corresponding phenols. This process involves the successive dehydrogenation of two saturated carbon-carbon bonds within the six-membered ring of cyclohexanones and utilizes molecular oxygen to drive the reaction cycle. It demonstrates a versatile and efficient approach for the synthesis of substituted phenols, providing a valuable complement to existing chemical methodologies.

2.
Talanta ; 280: 126681, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39142128

RESUMO

Mildewed tobacco leaves seriously impact on cigarette product quality and pose a health risk to person. However, early moldy tobacco leaves are hardly found by naked eyes in the workshop. In this work, we self-assemble AuAg nanoalloys on silicon wafers to construct Si/AuAg chips. The headspace-surface enhanced Raman scattering (SERS) protocol is developed to monitor volatile 1,2-dichloro-3-methoxybenzene (2,3-DCA) and 2,4,6-trichloroanisole (2,4,6-TCA) released from postharvest tobacco. Consequently, the visualization of the SERS peak at 1592 cm-1 assigned to ν(CC) after headspace collection for 10 min and the SERS intensity ratio of 1054 and 1035 cm-1 from 2,3-DCA and 2,4,6-TCA less than 0.5 could be used as indicators to predict early moldy tobacco. Additionally, with headspace collection time prolonging to 2 h, a SERS band at 682 cm-1 due to ν(CCl) of 2,4,6-TCA occurs, confirming the mildew of leaves. The headspace-SERS protocol paves a path for rapid and on-site inspection of the quality of tobacco leaves and cigarettes during storage with a portable Raman system.

3.
Angew Chem Int Ed Engl ; : e202412862, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39140466

RESUMO

In the field of biocatalysis, discovering novel reactivity from known enzymes has been a longstanding challenge. Fatty acid photo-decarboxylase from Chlorella variabilis (CvFAP) has drawn considerable attention as a promising photoenzyme with potential green chemistry applications; however, its non-natural reactivity has rarely been exploited to date. Herein we report a non-natural reductive dehalogenation (deacetoxylation) reactivity of CvFAP inspired by its natural oxidative decarboxylation process, enabling the  stereoselective synthesis of a series of chiral α-substituted tetralones with high yields (up to 99%) and e.r. values (up to 99:1). Mechanistic studies demonstrated that the native photoenzyme catalyzed the reductive dehalogenation via a novel mechanism involving oxidized state (FADox) / semiquinone state (FADsq) redox pair and an electron transfer (ET)/proton transfer (PT) process of radical termination, distinct from the previous reports. To our knowledge, this study represents a new example of CvFAP promiscuity, and thus expands the reactivity repertoire of CvFAP and highlights the versatility of CvFAP in asymmetric synthesis.

4.
J Environ Manage ; 367: 122076, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39111014

RESUMO

Rapid urbanization has highlighted ecological problems in the metropolitan area, with increasing landscape fragmentation and severe threats to ecosystem health (EH). Studying the spatio-temporal coupled relationship between landscape pattern and EH and its response to urbanization in the Fuzhou metropolitan area (FMA) can provide scientific reference for its long-term development planning. We examined the coupled relationship between landscape pattern and EH and its driving mechanism in the FMA at grid and township scales to address the gap. The results show that landscape heterogeneity, diversity, and dispersion are gradually increasing, and EH is rising progressively in the FMA from 2000 to 2020. The spatial distribution of landscape pattern indices and EH indicators showed a "high in the south and low in the north" trend. During the study period, the coupled relationship between landscape patterns and EH was increasingly powerful but with remarkable spatial heterogeneity. The study also found an inverted U-shaped relationship between urbanization and coupled relationships. Ecological landscapes' heterogeneity, diversity, and connectivity in low-urbanization areas are conducive to EH. The opposite is true for high-urbanization areas. This study provides a valuable reference for optimizing landscape planning and ecological management in metropolitan areas.


Assuntos
Ecossistema , Urbanização , Conservação dos Recursos Naturais
5.
Protein J ; 43(4): 683-696, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39068631

RESUMO

A recent study showed that just one point mutation F33 to Y in the complementarity-determining region 1 of heavy chain (H-CDR1) could lead to the auto-antibody losing its DNA binding ability. However, the potential molecular mechanisms have not been well elucidated. In this study, we investigated how the antibody lost the DNA binding ability caused by mutation F33 to Y in the H-CDR1. We found that the electrostatic force was not the primary driving force for the interaction between anti-DNA antibodies and the antigen single strand DNA (ssDNA), and that the H-CDR2 largely contributed to the binding of antigen ssDNA, even larger than H-CDR1. The H-F33Y mutation could increase the hydrogen-bond interaction but impair the pi-pi stacking interaction between the antibody and ssDNA. We further found that F33H, W98H and Y95L in the wiletype antibody could form the stable pi-pi stacking interaction with the nucleotide bases of ssDNA. However, the Y33 in mutant could not form the parallel sandwich pi-pi stacking interaction with the ssDNA. To further confirm the importance of pi-pi stacking, the wildtype antibody and the mutants (F33YH, F33AH, W98AH and Y95AL) were experimentally expressed in CHO cells and purified, and the results from ELISA clearly showed that all the mutants lost the ssDNA binding ability. Taken together, our findings may not only deepen the understanding of the underlying interaction mechanism between autoantibody and antigen, but also broad implications in the field of antibody engineer.


Assuntos
Regiões Determinantes de Complementaridade , DNA de Cadeia Simples , Mutação Puntual , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/química , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/química , Animais , Cricetulus , Células CHO , Autoanticorpos/genética , Autoanticorpos/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/química
6.
Behav Sci (Basel) ; 14(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-39062383

RESUMO

This study explores the learning effects of color cues in video lectures and their underlying mechanisms. With the rapid growth of online education, lifelong learning, and blended learning, video lectures have become integral to teaching and learning. Color, a crucial element in visual design, directs attention, organizes content, and integrates information. Evaluating 78 college students, we assessed learning performance by comparing video content with no-color, single-color, and multi-color cues using eye-tracking technology and cognitive load scales. Results indicate that students viewing videos with color cues demonstrated better retention and transfer test performance, while absence or excess of color cues increased cognitive load. These findings have practical implications for video producers and provide a theoretical foundation for enhancing learners' viewing experience and overall effectiveness. This study not only offers an in-depth analysis of color cue utilization in video lectures, highlighting their positive impact on learning outcomes but also introduces fresh perspectives for educational technology and cognitive psychology research. Future investigations should consider color cue effects in diverse cultural contexts and subject areas, exploring varied strategies to optimize the learning experience.

7.
BMC Infect Dis ; 24(1): 718, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039455

RESUMO

Mumps is a vaccine-preventable disease with high contagious capability. Its incidence declined rapidly since one dose of mumps vaccine was introduced into Expanded Program of Immunization (EPI) in 2008 in China. Nonetheless, the outbreaks of mumps remain frequent in China. Here we aim to assess herd immunity level followed by one-dose mumps ingredient vaccine and to elucidate the genetic characteristics of mumps viruses circulating in the post vaccine era in Jiangsu province of China. The complete sequences of mumps virus small hydrophobic(SH) gene were amplified and sequenced; coalescent-based Bayesian method was used to perform phylogenetic analysis with BEAST 1.84 software. Commercially available indirect enzyme-linked immune-sorbent IgG assay was used for the quantitative detection of IgG antibody against mumps virus. Our results show that genotype F was the predominant mumps viruses and belonged to indigenous spread, and most of Jiangsu sequences clustered together and formed a monophyly. The prevalence of mumps reached a peak in 2012 and subsequently declined, which presented an obvious different trajectory with virus circulating in other regions of China. The gene diversity of viruses circulating in Jiangsu province was far less than those in China. The antibody prevalence reached 70.42% in the general population during 2018 to 2020. The rising trend of antibody level was also observed. Although mumps antibody prevalence does not reach expected level, mumps virus faces higher pressure in Jiangsu province than the whole of China. To reduce further the prevalence of mumps viruses, two doses of mumps vaccine should be involved into EPI.


Assuntos
Anticorpos Antivirais , Vacina contra Caxumba , Vírus da Caxumba , Caxumba , Filogenia , Vírus da Caxumba/genética , Vírus da Caxumba/imunologia , Vírus da Caxumba/classificação , Humanos , China/epidemiologia , Caxumba/epidemiologia , Caxumba/virologia , Caxumba/imunologia , Caxumba/prevenção & controle , Anticorpos Antivirais/sangue , Vacina contra Caxumba/administração & dosagem , Vacina contra Caxumba/imunologia , Adulto , Adulto Jovem , Feminino , Masculino , Genótipo , Adolescente , Criança , Imunoglobulina G/sangue , Pessoa de Meia-Idade , Pré-Escolar , Imunidade Coletiva , Variação Genética , Proteínas Virais
8.
Genomics ; 116(5): 110906, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39084477

RESUMO

Enhancers are crucial in gene expression regulation, dictating the specificity and timing of transcriptional activity, which highlights the importance of their identification for unravelling the intricacies of genetic regulation. Therefore, it is critical to identify enhancers and their strengths. Repeated sequences in the genome are repeats of the same or symmetrical fragments. There has been a great deal of evidence that repetitive sequences contain enormous amounts of genetic information. Thus, We introduce the W2V-Repeated Index, designed to identify enhancer sequence fragments and evaluates their strength through the analysis of repeated K-mer sequences in enhancer regions. Utilizing the word2vector algorithm for numerical conversion and Manta Ray Foraging Optimization for feature selection, this method effectively captures the frequency and distribution of K-mer sequences. By concentrating on repeated K-mer sequences, it minimizes computational complexity and facilitates the analysis of larger K values. Experiments indicate that our method performs better than all other advanced methods on almost all indicators.

9.
Int J Biol Macromol ; 275(Pt 1): 133454, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964692

RESUMO

In the realization of the goal of circular economy, cellulose as one of sustainable biomass resources, have attracted much attention because of their abundant sources, biodegradability and renewability. However, the mechanical and waterproof performance of cellulose-based materials are usually not satisfying, which limits their high-value utilization. In this study, cellulose membrane with high-performance from the aspects of mechanical properties, water-resistance ability, oxygen barrier capacity and biodegradability, was prepared from bleached hardwood pulp (HBKP) in a AlCl3/ZnCl2/H2O solution. The AlCl3/ZnCl2/H2O acted as both solvent and catalyst to dissolve cellulose and facilitate the chemical crosslinking of epichlorohydrin (EPI) with cellulose, thus improved the overall performance of the obtained cellulose membrane. The addition sequence, amount and crosslinking time of EPI during chemical crosslinking had important effects on the properties of the membranes. When 7 wt% EPI was crosslinked for 24 h, the tensile stress reached 133 MPa and the strain reached 17 %. Moreover, the membrane had excellent oxygen insulation down to (1.1 ± 0.31) × 10-4 cm3/m2·d·Pa, and good water-resistance ability, no obvious swelling behavior after 450 days of immersion in distilled water. Furthermore, the membrane could be degraded by microorganisms in about 20 days. This cellulose-based membrane offers a sustainable and biodegradable packaging material.


Assuntos
Celulose , Membranas Artificiais , Celulose/química , Catálise , Água/química , Epicloroidrina/química , Resistência à Tração , Biodegradação Ambiental , Compostos de Zinco/química , Cloreto de Alumínio/química , Oxigênio/química , Embalagem de Produtos/métodos , Cloretos
10.
Front Oncol ; 14: 1325987, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988713

RESUMO

Objective: To investigate the feasibility and evaluate the safety and effectiveness of Computed Tomography (CT) guided125I radioactive particle implantation for treating lymph node metastases in radioiodine-refractory differentiated thyroid cancer (RAIR-DTC). To verify the accuracy of the computerized three-dimensional treatment planning system (TPS) in treating lymph node metastasis using125I particle implantation at the dosimetric level. Methods: A retrospective analysis was conducted on 42 patients with RAIR-DTC and lymph node metastases who were admitted to the General Hospital of the Northern Theater Command between December 2016 and January 2019. During this analysis, physicians utilized preoperative CT images to design an intraoperative plan using TPS. The dosimetric parameters of the postoperative plan were then compared to the preoperative plan. Additionally, this study examined the changes in tumor size and tumor-related marker Thyroglobulin (Tg) values in patients at 2, 6, and 12 months after the operation. Results: The number of125I radioactive particles implanted in 42 patients was 226, with an average of 14.5 (range 2.0-30.0) particles implanted per lesion. The local remission rates were 97.62% (41/42), 88.10% (37/42), and 85.71% (36/42) at 2, 6, and 12 months postoperatively, respectively. The volume of the lesions was (4.44 ± 1.57) cm3, (4.20 ± 1.70) cm3, and (4.23 ± 1.77) cm3at 2, 6, and 12 months after treatment, respectively, which significantly decreased from the preoperative baseline level of (6.87 ± 1.67) cm3(t-values: 9.466, 9.923, 7.566, all P<0.05). The Tg levels were 15.95 (5.45, 73.93) µg/L, 8.90 (2.20, 39.21) µg/L, and 6.00 (1.93, 14.18) µg/L at 2, 6, and 12 months after treatment, respectively, which were significantly lower than the preoperative baseline levels of 53.50 (20.94, 222.92) µg/L (Z values: -5.258, -5.009, -4.987, all P < 0.001). Postoperatively, Delivered to 90% of the GTV(D90) was slightly lower than the prescribed dose in 95.23% (40/42) of patients, but the difference was not statistically significant [(12,378.8 ± 3,182.0), (12,497.8 ± 1,686.4) cGy; t=0.251, P>0.05], and postoperative dose parameters delivered to 100% of the gross tumor volume (GTV)(D100) (6,881.5 ± 1,381.8) cGy, the volume percentages of GTV receiving 150% of the prescribed dose(V150) (58.5 ± 18.40)%) were lower than the preoperative plan D100 (8,085.8 ± 2,330.0) cGy, V150 (66.5 ± 17.70)%; t-value=8.913 and 3.032, both P<0.05; the remaining indicators were not significantly different from the preoperative plan (the differences in the number of implanted particles, Planning Target Volume(PTV), the volume percentages of GTV receiving 100% of the prescribed dose(V100), Homogeneity Index(HI)were not statistically significant (t/Z = -0.593, -1.604, 1.493, -0.663, all P>0.05). Conclusion: Referring to the TPS preoperative plan, the125I particle implantation therapy for RAIR-DTC lymph node metastasis can achieve the expected dose distribution, ensuring precise short-term local tumor control efficacy.

11.
Sensors (Basel) ; 24(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39000962

RESUMO

As one of the important lakes in the "One Lake and Two Seas" of the Inner Mongolia Autonomous Region, the monitoring of water quality in Lake Daihai has attracted increasing attention, and the concentration of chlorophyll-a directly affects the water quality, making the monitoring of chlorophyll-a concentration in Lake Daihai particularly crucial. Traditional methods of monitoring chlorophyll-a concentration are not only inefficient but also require significant human and material resources. Remote sensing technology has the advantages of wide coverage and short update cycles. For lakes such as Daihai with a high salinity content, salinity is considered a key factor when inverting the concentration of chlorophyll-a. In this study, machine learning models, including model stacking from ensemble learning, a ridge regression model, and a random forest model, were constructed. After comparing the training accuracy of the three models on Zhuhai-1 satellite data, the random forest model, which had the highest accuracy, was selected as the final training model. By comparing the accuracy changes before and after adding salinity factors to the random forest model, a high-precision model for inverting chlorophyll-a concentration in hypersaline lakes was obtained. The research results show that, without considering the salinity factor, the root mean square error (RMSE) of the model was 0.056, and the coefficient of determination (R2) was 0.64, indicating moderate model performance. After adding the salinity factor, the model accuracy significantly improved: the RMSE decreased to 0.047, and the R2 increased to 0.92. This study provides a solid basis for the application of remote sensing technology in hypersaline aquatic environments, confirming the importance of considering salinity when estimating chlorophyll-a concentration in hypersaline waters. This research helps us gain a deeper understanding of the water quality and ecosystem evolution in Daihai Lake.

12.
Neural Netw ; 178: 106468, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38943862

RESUMO

Knowledge graph reasoning, vital for addressing incompleteness and supporting applications, faces challenges with the continuous growth of graphs. To address this challenge, several inductive reasoning models for encoding emerging entities have been proposed. However, they do not consider the multi-batch emergence scenario, where new entities and new facts are usually added to knowledge graphs (KGs) in multiple batches in the order of their emergence. To simulate the continuous growth of knowledge graphs, a novel multi-batch emergence (MBE) scenario has recently been proposed. We propose a path-based inductive model to handle multi-batch entity growth, enhancing entity encoding with type information. Specifically, we observe a noteworthy pattern in which entity types at the head and tail of the same relation exhibit relative regularity. To utilize this regularity, we introduce a pair of learnable parameters for each relation, representing entity type features linked to the relation. The type features are dedicated to encoding and updating the features of entities. Meanwhile, our model incorporates a novel attention mechanism, combining statistical co-occurrence and semantic similarity of relations effectively for contextual information capture. After generating embeddings, we employ reinforcement learning for path reasoning. To reduce sparsity and expand the action space, our model generates soft candidate facts by grounding a set of soft path rules. Meanwhile, we incorporate the confidence scores of these facts in the action space to facilitate the agent to better distinguish between original facts and rule-generated soft facts. Performances on three multi-batch entity growth datasets demonstrate robust performance, consistently outperforming state-of-the-art models.


Assuntos
Redes Neurais de Computação , Algoritmos , Semântica , Conhecimento , Humanos , Aprendizado de Máquina , Simulação por Computador
13.
China CDC Wkly ; 6(19): 418-423, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38854752

RESUMO

What is already known on this topic?: In China, there is limited data available on the use and coverage of the non-program, combined diphtheria, tetanus toxoid, acellular pertussis adsorbed, inactivated poliovirus and haemophilus influenzae type b (DTaP-IPV/Hib) pentavalent vaccine, and its role as a substitute for the separately administered standalone program vaccines. What is added by this report?: We evaluated the use and coverage of the pentavalent vaccine in nine provincial-level administrative divisions (PLADs) spanning eastern, central, and western China from 2019 to 2021. Initial use and coverage were low, but demonstrated annual growth albeit with regional and urban-rural discrepancies. The pentavalent vaccine was increasingly substituted for standalone vaccines over the course of this period. What are the implications for public health practice?: Parents in China are increasingly opting to replace the standard program vaccines with voluntarily purchased combination vaccines, particularly the pentavalent vaccine. The development of combination vaccines should thus be promoted in China, as it could enhance utilization and coverage rates, and decrease the economic burden.

14.
Int J Biol Macromol ; 272(Pt 2): 132912, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38851617

RESUMO

The unique molecular structure of cellulose makes it challenging to dissolve at room temperature (R.T.), and the dissolution mechanism remains unclear. In this study, we employed ZnCl2 aqueous solution for cellulose dissolution at R.T., proposing a novel four-stage dissolution mechanism. The efficient dissolution of cellulose in ZnCl2 aqueous solution at R.T. involves four indispensable stages: rapid migration of hydrated Zn2+ ions towards cellulose, sufficient penetration between cellulose sheets, strong interaction with cellulose hydroxyl groups, and effective dispersion of separated cellulose chains. The proposed four-stage dissolution mechanism was validated through theoretical calculations and experimental evidence. The hydrated Zn2+ ions in ZnCl2 + 3.5H2O solvent exhibited ideal migration, penetration, interaction, and dispersion abilities, resulting in efficient cellulose dissolution at R.T. Moreover, only slight degradation of cellulose occurred in ZnCl2 + 3.5H2O at R.T. Consequently, the regenerated cellulose materials obtained from ZnCl2 + 3.5H2O (R.T.) exhibited better mechanical properties. Notably, the solvent recovery rate reached about 95 % based on previous usage during five cycles. The solvent is outstanding for its green, low-cost, efficiency, simplicity, R.T. conditions and recyclability. This work contributes to a better understanding of the cellulose dissolution mechanisms within inorganic salt solvents at R.T., thereby guiding future development efforts towards greener and more efficient cellulosic solvents.


Assuntos
Celulose , Cloretos , Solubilidade , Temperatura , Água , Compostos de Zinco , Celulose/química , Compostos de Zinco/química , Cloretos/química , Água/química , Soluções , Solventes/química , Zinco/química
15.
J Colloid Interface Sci ; 670: 311-322, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38763027

RESUMO

The green synthesis strategy for cellulose-containing hydrogel electrolytes is significant for effectively managing resources, energy, and environmental concerns in the contemporary world. Herein, we propose an all-green strategy using AlCl3/ZnCl2/H2O solvent to create cellulose/polyacrylamide-based hydrogel (AZ-Cel/PAM) with expanded hierarchical topologies. The aqueous AlCl3/ZnCl2 facilitates the efficient dissolution of cellulose at room temperature, and the dispersed Al3+-Zn2+ ions autocatalytic system catalyzes in-situ polymerization of acrylamide (AM) monomer. This expands the AM network within the cellulose framework, forming multiple bonding interactions and stable ion channels. The resulting hybrid hydrogel exhibits improved mechanical properties (tensile strength of 56.54 kPa and compressive strength of 359.43 kPa) and enhanced ionic conductivity (1.99 S/m). Furthermore, it also demonstrates excellent adhesion, freeze resistance (-45 °C), and water retention capabilities. Quantum simulations further clarify the mechanical composition and ion transport mechanism of AZ-Cel/PAM hydrogels. The assembled supercapacitor with the hydrogel electrolyte, demonstrates an ideal area-specific capacitance of 203.80 mF/cm2. This all-green strategy presents a novel approach to developing sustainable energy storage devices.

16.
New Microbiol ; 47(1): 68-79, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38700886

RESUMO

We aimed to investigate the role of Synbiotic preparations on the interaction of gut microbiota with AD development. APP/PS1 mice were randomized into APP/PS1 and Synbiotics groups, and C57BL/6J mice were used as wild type (WT) control group. The mice in the Synbiotics group and the APP/PS1 group were given Synbiotics and xylo-oligosaccharides for 3 months, respectively. The mice in the WT group were given the same amount of normal saline. Cognitive function was measured. Positron emission computed tomography/magnetic resonance imaging (PET/MRI) was used to detect fasting blood glucose level. Immunohistochemical assay, ELISA, western blot and qRT-PCR were carried out to detect inflammatory factors. DNA extraction of fecal sample was performed to carry out sequencing. Bioinformatics analysis, metabolites sample preparation and Liquid Chromatograph Mass Spectrometer (LC/MS) analysis were also performed. Synbiotics treatment can significantly ameliorate learning and memory competence by inhibiting Aß protein deposition. Different bacteria in the intestine were significantly improved and changes in gut microbiota can affect the intestinal metabolism to affect multiple potential pathways after Synbiotics treatment. Synbiotics treatment can activate peroxisome proliferator activated receptor (PPARs) signaling pathway and significantly reduce neuroinflammation in APP/PS1 mice brains. Synbiotics treatment can effectively reduce neuro-inflammatory response through the regulation of intestinal microflora to delay AD development.


Assuntos
Doença de Alzheimer , Modelos Animais de Doenças , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Receptores Ativados por Proliferador de Peroxissomo , Simbióticos , Animais , Camundongos , Simbióticos/administração & dosagem , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Progressão da Doença , Transdução de Sinais , Masculino , Camundongos Transgênicos
17.
Int J Biol Macromol ; 270(Pt 2): 132416, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754653

RESUMO

Inflammation-related bone defects often lead to poor osteogenesis. Therefore, it is crucial to reduce the inflammation response and promote the osteogenic differentiation of stem/progenitor cells to revitalize bone physiology. Here, a kind of hybrid nano-hydroxyapatite was prepared using the confined phosphate ion release method with the participation of fucoidan, a marine-sourced polysaccharide with anti-inflammation property. The physicochemical analyses confirmed that the fucoidan hybrid nano-hydroxyapatite (FC/n-HA) showed fine needle-like architectures. With a higher amount of fucoidan, the crystal size and crystallinity of the FC/n-HA reduced while the liquid dispersibility was improved. Cell experiences showed that FC/n-HA had an optimal cytocompatibility at concentration of 50 µg/mL. Moreover, the lipopolysaccharide-induced cellular inflammatory model with PDLSCs was established and used to evaluate the anti-inflammatory and osteogenic properties. For the 1%FC/n-HA group, the expression levels of TNF-α and IL-1ß were significantly reduced at 24 h, while the expression of alkaline phosphatase of PDLSCs was significantly promoted at days 3 and 7, and calcium precipitates was enhanced at 21 days. In this study, the FC/n-HA particles showed effective anti-inflammatory properties and facilitated osteogenic differentiation of PDLSCs, indicating which has potential application in treating bone defects associated with inflammation, such as periodontitis.


Assuntos
Diferenciação Celular , Durapatita , Nanopartículas , Osteogênese , Ligamento Periodontal , Polissacarídeos , Células-Tronco , Humanos , Osteogênese/efeitos dos fármacos , Polissacarídeos/farmacologia , Polissacarídeos/química , Durapatita/química , Durapatita/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/metabolismo , Nanopartículas/química , Ligamento Periodontal/citologia , Ligamento Periodontal/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/patologia , Células Cultivadas
18.
Int Med Case Rep J ; 17: 439-445, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765866

RESUMO

Background: Although percutaneous osteoplasty (POP) has been widely accepted and is now being performed for the treatment of painful bone metastases outside the spine. It is emerging as one of the most promising procedures for patients with painful bone metastasis who are unsuitable for surgery or who show resistance to radiotherapy and/or analgesic therapies. However, there are only scarce reports regarding osteoplasty in painful sternal metastases. Subjects and Method: We report four patients with sternal metastases suffered with severe pain of anterior chest wall. The original tumors included lung cancer and thyroid cancer. For the initially pain medication failing, all the four patients received POP procedure under fluoroscopic and cone-beam CT (CBCT) guidance, and obtained satisfying resolution of painful symptoms at 6-month postop follow-up. Conclusion: POP is a safe and effective treatment for pain caused by metastatic bone tumors in the sternum. In practice, however, percutaneous puncture of pathologic sternal fractures can be a challenge because of the long flat contour and the defacement by lytic tumor of bony landmarks. We find that the use of fluoroscopic and CBCT can facilitate POP for flat bone fractures with displacing the trajectory planning, needle advancement, and cement delivery in time.

19.
Sensors (Basel) ; 24(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38793982

RESUMO

The main aim of this study was to utilize remote sensing data to establish regression models through machine learning to predict locust density in the upcoming year. First, a dataset for monitoring grassland locust density was constructed based on meteorological data and multi-source remote sensing data in the study area. Subsequently, an SVR (support vector regression) model, BP neural network regression model, random forest regression model, BP neural network regression model with the PCA (principal component analysis), and deep belief network regression model were built on the dataset. The experimental results show that the random forest regression model had the best prediction performance among the five models. Specifically, the model achieved a coefficient of determination (R2) of 0.9685 and a root mean square error (RMSE) of 1.0144 on the test set, which were the optimal values achieved among all the models tested. Finally, the locust density in the study area for 2023 was predicted and, by comparing the predicted results with actual measured data, it was found that the prediction accuracy was high. This is of great significance for local grassland ecological management, disaster warning, scientific decision-making support, scientific research progress, and sustainable agricultural development.

20.
Foods ; 13(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731658

RESUMO

Parkinson's disease (PD), the second most common neurodegenerative disorder, is linked to α-synuclein (α-Syn) aggregation. Despite no specific drug being available for its treatment, curcumin, from the spice turmeric, shows promise. However, its application in PD is limited by a lack of understanding of its anti-amyloidogenic mechanisms. In this study, we first reconstructed the liquid-liquid phase separation (LLPS) of α-Syn in vitro under different conditions, which may be an initial step in entraining the pathogenic aggregation. Subsequently, we evaluated the effects of curcumin on the formation of droplets, oligomers, and aggregated fibers during the LLPS of α-synuclein, as well as its impact on the toxicity of aggregated α-synuclein to cultured cells. Importantly, we found that curcumin can inhibit amyloid formation by inhibiting the occurrence of LLPS and the subsequent formation of oligomers of α-Syn in the early stages of aggregation. Finally, the molecular dynamic simulations of interactions between α-Syn decamer fibrils and curcumin showed that van der Waal's interactions make the largest contribution to the anti-aggregation effect of curcumin. These results may help to clarify the mechanism by which curcumin inhibits the formation of α-Syn aggregates during the development of PD.

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