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1.
World J Psychiatry ; 14(3): 409-420, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38617988

RESUMO

BACKGROUND: Dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis (MHD) that significantly affect their quality of life (QOL). High levels of social support can significantly improve the physical and mental well-being of patients undergoing MHD. Currently, there is limited research on how social support mediates the relationship between dysphoria, despondency, and overall QOL in patients undergoing MHD. It is imperative to investigate this mediating effect to mitigate dysphoria and despondency in patients undergoing MHD, ultimately enhancing their overall QOL. AIM: To investigate the mediating role of social support in relationships between dysphoria, despondency, and QOL among patients undergoing MHD. METHODS: Participants comprised 289 patients undergoing MHD, who were selected using a random sampling approach. The Social Support Rating Scale, Self-Rating Anxiety Scale, Self-Rating Depression Scale, and QOL Scale were administered. Correlation analysis was performed to examine the associations between social support, dysphoria, despondency, and QOL in patients undergoing MHD. To assess the mediating impact of social support on dysphoria, despondency, and QOL in patients undergoing MHD, a bootstrap method was applied. RESULTS: Significant correlations among social support, dysphoria, despondency, and quality in patients undergoing MHD were observed (all P < 0.01). Dysphoria and despondency negatively correlated with social support and QOL (P < 0.01). Dysphoria and despondency had negative predictive impacts on the QOL of patients undergoing MHD (P < 0.05). The direct effect of dysphoria on QOL was statistically significant (P < 0.05). Social support mediated the relationship between dysphoria and QOL, and this mediating effect was significant (P < 0.05). Similarly, the direct effect of despondency on QOL was significant (P < 0.05). Moreover, social support played a mediating role between despondency and QOL, with a significant mediating effect (P < 0.05). CONCLUSION: These findings suggest that social support plays a significant mediating role in the relationship between dysphoria, despondency, and QOL in patients undergoing MHD.

2.
Photochem Photobiol ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528682

RESUMO

Combining photodynamic antimicrobials with nonwovens is prospective. However, common photosensitizers still have drawbacks such as poor photoactivity and the inability to charge. In this study, a photodynamic and high-efficiency antimicrobial protective material was prepared by grafting bis benzophenone-structured 4,4-terephthaloyl diphthalic anhydride (TDPA) photosensitizer, and antimicrobial agent chlorogenic acid (CA) onto spunbond-meltblown-spunbond (SMS) membranes. The charging rates for ·OH and H2O2 were 6377.89 and 913.52 µg/g/h. The light absorption transients structural storage remained above 69% for 1 month. High electrical capacity remained after seven cycles indicating its rechargeability and recyclability. The SMS/TDPA/CA membrane has excellent bactericidal performance when under illumination or lightless conditions, and the bactericidal efficiency of Escherichia coli and Staphylococcus aureus reached over 99%. The construction of self-disinfection textiles based on the photodynamic strategies proposed in this paper is constructive for expanding and promoting the application of textile materials in the medical field.

3.
Food Chem X ; 22: 101259, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38444556

RESUMO

This research sought to examine how the physicochemical characteristics of soy globulins and different processing techniques influence the gel properties of soy yogurt. The goal was to improve these gel properties and rectify any texture issues in soy yogurt, ultimately aiming to produce premium-quality plant-based soy yogurt. In this research study, the investigation focused on examining the impact of 7S/11S, homogenization pressure, and glycation modified with glucose on the gel properties of soy yogurt. A plant-based soy yogurt with superior gel and texture properties was successfully developed using a 7S/11S globulin-glucose conjugate at a 1:3 ratio and a homogenization pressure of 110 MPa. Compared to soy yogurt supplemented with pectin or gelatin, this yogurt demonstrated enhanced characteristics. These findings provide valuable insights into advancing plant protein gels and serve as a reference for cultivating new soybean varieties by soybean breeding experts.

4.
Langmuir ; 40(14): 7384-7394, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38530344

RESUMO

Photocatalytic technology is a popular research area for converting solar energy into environmentally friendly chemicals and is considered the greenest approach for producing H2O2. However, the corresponding reactive oxygen species (ROS) and pathway involved in the photocatalytic generation of H2O2 by the Bi2.15WO6-glucose system are still not clear. Quenching experiments have established that neither •OH nor h+ contribute to the formation of H2O2, and show that the formed surface superoxo (≡Bi-OO•) and peroxo (≡Bi-OOH) species are the predominant ROS in H2O2 generation. In addition, various characterizations indicate the enhanced electron-transfer on the surface of Bi2.15WO6 with increasing contents of glucose via the ligand-to-metal charge transfer pathway, confirming H-transfer from glucose to ≡Bi-OO• or ≡Bi-OOH. The increased production of H2O2 with decreasing bond dissociation energy (BDEO-H) values of various phenolic compounds again supports the H-transfer mechanism from phenolic compounds to ≡Bi-OO• and then to ≡Bi-OOH. DFT calculations further reveal that on the Bi2.15WO6 surface, oxygen is sequentially reduced to ≡Bi-OO• and ≡Bi-OOH, while H-transfer from H2O or glucose to ≡Bi-OO• and ≡Bi-OOH, resulting in the production of H2O2. The lower energy barrier of H-transfer from adsorbed glucose (0.636 eV) than that from H2O (1.157 eV) indicates that H-transfer is more favorable from adsorbed glucose. This work gives new insight into the photocatalytic generation of H2O2 by Bi2.15WO6 in the presence of glucose/phenolic compounds via the H-abstraction pathway.

5.
Dev Comp Immunol ; 154: 105142, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38309673

RESUMO

The fall armyworm, Spodoptera frugiperda, poses a significant threat as a highly destructive agricultural pest in many countries. Understanding the complex interplay between the insect immune system and entomopathogens is critical for optimizing biopesticide efficacy. In this study, we identified a novel microbial binding protein, SfMBP, in S. frugiperda. However, the specific role of SfMBP in the immune response of S. frugiperda remains elusive. Encoded by the LOC118269163 gene, SfMBP shows significant induction in S. frugiperda larvae infected with the entomopathogen Beauveria bassiana. Consisting of 115 amino acids with a signal peptide, an N-terminal flexible region and a C-terminal ß-sheet, SfMBP lacks any known functional domains. It is expressed predominantly during early larval stages and in the larval epidermis. Notably, SfMBP is significantly induced in larvae infected with bacteria and fungi and in SF9 cells stimulated by peptidoglycan. While recombinant SfMBP (rSfMBP) does not inhibit bacterial growth, it demonstrates binding capabilities to bacteria, fungal spores, peptidoglycan, lipopolysaccharides, and polysaccharides. This binding is inhibited by monosaccharides and EDTA. Molecular docking reveals potential Zn2+-interacting residues and three cavities. Furthermore, rSfMBP induces bacterial agglutination in the presence of Zn2+. It also binds to insect hemocytes and SF9 cells, enhancing phagocytosis and agglutination responses. Injection of rSfMBP increased the survival of S. frugiperda larvae infected with B. bassiana, whereas blocking SfMBP with the antibody decreased survival. These results suggest that SfMBP acts as a pattern recognition receptor that enhances pathogen recognition and cellular immune responses. Consequently, this study provides valuable insights for the development of pest control measures.


Assuntos
Proteínas de Transporte , Mariposas , Animais , Spodoptera/fisiologia , Proteínas de Transporte/metabolismo , Simulação de Acoplamento Molecular , Peptidoglicano/metabolismo , Mariposas/metabolismo , Larva/metabolismo , Insetos/metabolismo , Receptores de Reconhecimento de Padrão/genética , Receptores de Reconhecimento de Padrão/metabolismo
6.
Glob Chang Biol ; 30(2): e17192, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38369693

RESUMO

Obtaining a holistic understanding of the impacts of atmospheric nitrogen deposition on multiple ecosystem services of forest is essential for developing comprehensive and sustainable strategies, particularly in heavy N deposition regions such as subtropical China. However, such impacts remain incompletely understood, with most previous studies focus on individual ecosystem function or service via understory N addition experiments. To address this knowledge gap, we quantified the effects of over-canopy and understory N additions on multiple ecosystem services based on a 7-year large-scale field experiment in a typical subtropical forest. Our results showed continued over-canopy N addition with 50 kg ha-1 year-1 over a period of 4-7 years significantly increased plant nutrient retention, but did not affect the services of soil nutrient accumulation, water yield, C sequestration (in plants and soil), or oxygen release. There were trade-offs between the soil and plant on providing the services of nutrient accumulation/retention and C sequestration under over-canopy N addition. However, without uptake and retention of tree canopy, the trade-off between soil and plant were more weaken under the understory N addition with 50 kg ha-1 year-1 , and their relationships were even synergetic under the understory N addition with 25 kg ha-1 year-1 . The results suggest that understory N addition cannot accurately simulate the effects of atmospheric N deposition on multiple services, along with mutual relationships. Interestingly, the services of plant N, P retention, and C sequestration exhibited a synergetic increase under the over-canopy N addition but a decrease under the understory N addition. Our results also found tree layer plays a primary role in providing plant nutrient retention service and is sensitive to atmospheric N deposition. Further studies are needed to investigate the generalized effects of forest canopy processes on alleviating the threaten of global change factors in different forest ecosystems.


Assuntos
Ecossistema , Nitrogênio , Nitrogênio/análise , Florestas , Árvores , Plantas , Solo
7.
Org Biomol Chem ; 22(4): 741-744, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38170630

RESUMO

An unexpected isomerization of azomethine ylides generated in situ from isatin with indoline-2-carboxylic acid has been disclosed, providing direct access to N-functionalized indole scaffolds. This protocol has good functional group tolerance and provides various 3-(1H-indol-1-yl)indolin-2-one derivatives in moderate to high yields simply by using alcohol as the solvent, with no additional additive being required.

8.
J Med Virol ; 96(1): e29396, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38235848

RESUMO

The RNA-dependent RNA polymerase (RdRp) is a crucial element in the replication and transcription of RNA viruses. Although the RdRps of lethal human coronaviruses severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), SARS-CoV, and Middle East respiratory syndrome coronavirus (MERS-CoV) have been extensively studied, the molecular mechanism of the catalytic subunit NSP12, which is involved in pathogenesis, remains unclear. In this study, the biochemical and cell biological results demonstrate the interactions between SARS-CoV-2 NSP12 and seven host proteins, including three splicing factors (SLU7, PPIL3, and AKAP8). The entry efficacy of SARS-CoV-2 considerably decreased when SLU7 or PPIL3 was knocked out, indicating that abnormal splicing of the host genome was responsible for this occurrence. Furthermore, the polymerase activity and stability of SARS-CoV-2 RdRp were affected by the three splicing factors to varying degrees. In addition, NSP12 and its homologues from SARS-CoV and MERS-CoV suppressed the alternative splicing of cellular genes, which were influenced by the three splicing factors. Overall, our research illustrates that SARS-CoV-2 NSP12 can engage with various splicing factors, thereby impacting virus entry, replication, and gene splicing. This not only improves our understanding of how viruses cause diseases but also lays the foundation for the development of antiviral therapies.


Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , COVID-19/genética , RNA Polimerase Dependente de RNA/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Fatores de Processamento de RNA
9.
Org Lett ; 26(3): 625-630, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38206574

RESUMO

We report a general copper/iodine co-catalyzed oxygenative transannulation strategy using readily available tryptamines. Molecular oxygen and water are used as oxygen sources and provide direct access to the donaxaridine scaffold and its derivatives. This methodology is applied to the efficient synthesis of the natural products donaxaridine, chimonamidine, donaxanine, donaxarine, and aline in just one or two steps. The tryptamines, albeit with oxy-sensitive dialkyl N-H groups, are selectively oxidized through a single-electron transfer dioxygenation process.

10.
J Magn Reson Imaging ; 59(3): 1034-1042, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37272790

RESUMO

BACKGROUND: The assessment of resectability after neoadjuvant chemotherapy of hepatoblastoma is dependent on Post-Treatment EXTENT of Disease (POSTTEXT) staging and its annotation factors P (portal venous involvement) and V (hepatic venous/inferior vena cava [IVC] involvement), but MR performance in assessing them remains unclear. PURPOSE: To assess the diagnostic performance of contrast-enhanced MR imaging for preoperative POSTTEXT staging and diagnosing vascular involvement in terms of annotation factors P and V in pediatric hepatoblastoma following neoadjuvant chemotherapy. STUDY TYPE: Retrospective. SUBJECTS: Thirty-five consecutive patients (17 males, median age, 24 months; age range, 6-98 months) with proven hepatoblastoma underwent preoperative MR imaging following neoadjuvant chemotherapy. FIELD STRENGTH/SEQUENCE: 3.0 T; T2-weighted imaging (T2WI), T2WI with fat suppression, diffusion weighted imaging, radial stack-of-the-star/Cartesian 3D Dixon T1-weighted gradient echo imaging. ASSESSMENT: Three radiologists independently assessed the POSTTEXT stages and annotation factors P and V based on the 2017 PRE/POSTTEXT system. The sensitivities and specificities were calculated for 1) diagnosing each POSTTEXT stage; 2) discrimination of stages III and IV (advanced) from those stages I and II (non-advanced) hepatoblastomas; and 3) annotation factors P and V. The combination of pathologic findings and surgical records served as the reference standard. STATISTICAL TESTS: Sensitivity, specificity, Fleiss kappa test. RESULTS: The sensitivity and specificity ranges for discriminating advanced from non-advanced hepatoblastomas were 73.3%-80.0% and 80.0%-90.0%, respectively. For annotation factor P, they were 66.7%-100.0% and 90.6%, respectively. For factor V, they were 75.0% and 67.7%-83.9%, respectively. There was excellent, substantial, and moderate agreement on POSTTEXT staging (Fleiss kappa = 0.82), factors P (Fleiss kappa = 0.64), and factors V (Fleiss kappa = 0.60), respectively. DATA CONCLUSION: MR POSTTEXT provides reliable discrimination between advanced and non-advanced tumors, and MR has moderate to excellent specificity at identifying portal venous and hepatic venous/IVC involvement. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Masculino , Criança , Humanos , Pré-Escolar , Lactente , Hepatoblastoma/tratamento farmacológico , Hepatoblastoma/patologia , Hepatoblastoma/cirurgia , Terapia Neoadjuvante , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Veias Hepáticas , Sensibilidade e Especificidade , Neoplasias Hepáticas/patologia , Estadiamento de Neoplasias
11.
ISA Trans ; 144: 352-363, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37907386

RESUMO

The three-phase four-wire voltage source inverter (3P4W VSI) is widely used in applications like uninterrupted power supply (UPS) and bidirectional onboard charger. The increasing power density demand requires higher switching frequency and lower switching loss. To fulfill the conflicting objectives, two-fold methodology is proposed in this paper: 1) SiC/Si hybrid switches (HyS) together with recently reported gate trigger are reported for the first time in the 3P4W VSI; 2) the natural point voltage is controlled to track a sinusoidal voltage with the frequency equal to 3 times of fundamental frequency in order to achieve higher DC-bus voltage utilization rate, and further reduce the switching loss. The traditional PI controller is very hard to achieve desired performance due to both the nonlinearity and the variant reference of the natural point voltage control system. Thereby, the super-twisting sliding mode control (ST-SMC) is proposed in this paper to achieve desired tracking performance and fast dynamic response. The effectiveness and superiority of the system are verified by both simulation and experiment comparison with the existing methods using a 5 kW prototype.

12.
Sci Data ; 10(1): 921, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129455

RESUMO

Santalum album is a well-known aromatic and medicinal plant that is highly valued for the essential oil (EO) extracted from its heartwood. In this study, we present a high-quality chromosome-level genome assembly of S. album after integrating PacBio Sequel, Illumina HiSeq paired-end and high-throughput chromosome conformation capture sequencing technologies. The assembled genome size is 207.39 M with a contig N50 of 7.33 M and scaffold N50 size of 18.31 M. Compared with three previously published sandalwood genomes, the N50 length of the genome assembly was longer. In total, 94.26% of the assembly was assigned to 10 pseudo-chromosomes, and the anchor rate far exceeded that of a recently released value. BUSCO analysis yielded a completeness score of 94.91%. In addition, we predicted 23,283 protein-coding genes, 89.68% of which were functionally annotated. This high-quality genome will provide a foundation for sandalwood functional genomics studies, and also for elucidating the genetic basis of EO biosynthesis in S. album.


Assuntos
Genoma de Planta , Óleos Voláteis , Santalum , Sesquiterpenos , Cromossomos , Genômica , Filogenia , Santalum/genética
13.
Biomed Mater ; 18(6)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37908154

RESUMO

Bone tissue engineering scaffolds should have bone compatibility, biological activity, porosity, and degradability. In this study, flake-like hydroxyapatite was synthesized by hydrothermal method and mixed with sodium alginate to make a gel, which was injected into a hollow braid. Porous and degradable SA/n-Hap woven scaffolds were prepared by freeze-drying technology. The morphology of hydroxyapatite was characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and x-ray diffraction. The scaffolds were characterized by an improved liquid replacement method, compression test, and degradation test. The results showed that the hydroxyapatite synthesized at 160 °C had a scaly morphology. The prepared scaffold had a pore size of 5-100 µm, a porosity of 60%-70%, and a swelling rate of more than 300%. After 21 d the degradation rate reached 5.54%, and a cell survival rate of 214.98%. In summary, it is feasible to prepare porous bone scaffolds for potential bone tissue engineering. This study shows the feasibility of applying textile structures to the field of tissue scaffolds and provides a new idea for the application structure of tissue engineering scaffolds.


Assuntos
Durapatita , Engenharia Tecidual , Engenharia Tecidual/métodos , Durapatita/química , Tecidos Suporte/química , Osso e Ossos , Difração de Raios X , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Angew Chem Int Ed Engl ; 62(51): e202313687, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37950324

RESUMO

Herein, we report an unprecedented skeletal rearrangement reaction of tetrahydro-ß-carbolines enabled by copper-catalyzed single-electron oxidative oxygenation, in which H2 O and O2 act as oxygen sources to generate a unique 2-hydroxyl-3-peroxide indoline intermediate. The synthetic reactivity of 2-hydroxyl-3-peroxide indoline species was demonstrated by a unique multi-step bond cleavage and formation cascade. Using a readily available copper catalyst under open-air conditions, highly important yet synthetically difficult spiro[pyrrolidone-(3,1-benzoxazine)] products were obtained in a single operation. The synthetic utility of this methodology is demonstrated by the efficient synthesis of the natural products donaxanine and chimonamidine, as well as the 3-hydroxyl-pyrroloindoline scaffold, in just one or two steps.

15.
Sci Data ; 10(1): 819, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993453

RESUMO

The application of DNA barcoding has been significantly limited by the scarcity of reliable specimens and inadequate coverage and replication across all species. The deficiency of DNA barcode reference coverage is particularly striking for highly biodiverse subtropical and tropical regions. In this study, we present a comprehensive barcode library for woody plants in tropical and subtropical China. Our dataset includes a standard barcode library comprising the four most widely used barcodes (rbcL, matK, ITS, and ITS2) for 2,520 species from 4,654 samples across 49 orders, 144 families, and 693 genera, along with 79 samples identified at the genus level. This dataset also provides a super-barcode library consisting of 1,239 samples from 1,139 species, 411 genera, 113 families, and 40 orders. This newly developed library will serve as a valuable resource for DNA barcoding research in tropical and subtropical China and bordering countries, enable more accurate species identification, and contribute to the conservation and management of tropical and subtropical forests.


Assuntos
Código de Barras de DNA Taxonômico , Plantas , China , Florestas , Filogenia , Plantas/genética , Madeira
16.
Langmuir ; 39(41): 14638-14651, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37782834

RESUMO

In harsh environments, it is crucial to design personal protective materials that possess both puncture/cut resistance and chemical resistance. In order to fulfill these requirements, this study introduces an innovative approach that combines hydrophobically modified rigid nanoparticles with thermoplastic polyurethane elastomers. These materials are then laminated with high-performance aramid fabrics through a scraping process, resulting in a multifunctional composite with puncture/cut resistance, superhydrophobicity, self-cleaning properties, and acid/alkali resistance. The quasi-static puncture tests conducted reveal the remarkable performance of the composite. The maximum spike puncture resistance reaches 267.62 N, which is 17.14 times higher than that of the pure fabric (15.61 N). Similarly, the maximum knife puncture resistance reaches 115.02 N, exhibiting a 5.01 times increase compared to that of the pure aramid fabric (22.97 N). Furthermore, the results obtained from the yarn pull-out, fabric burst strength, and tearing experiments demonstrate that the incorporation of rigid nanoparticles significantly enhances the friction between the yarns, enabling a greater number of yarns to participate in the dissipation of impact energy. As a result, the puncture resistance of the fabric is greatly improved. Significantly, the composite exhibits sustained superhydrophobicity even after exposure to harsh chemicals such as concentrated sulfuric acid and sodium hydroxide as well as undergoing cyclic mechanical wear. These findings highlight the composite's exceptional durability and resistance to corrosion. Overall, this study offers insights and methods for the development of multifunctional flexible puncture-resistant equipment for individuals.

17.
J Biomater Sci Polym Ed ; 34(18): 2498-2515, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37795599

RESUMO

When impaired bones are grafted with bone scaffolds, the behaviors of osteoblast are dependent on the implant materials and surface morphology. To this end, we modulated the surface morphology of scaffolds that promote cell growth. In this study, ice-template and spraying method methods are employed to coat different proportions of PDA and PPy over the PLA/PVA weaving scaffolds, after which HA is Coated over via the electrochemical deposition, forming weaving scaffolds with electrically conductive PDA/PPy/HA coating. The test results indicate that with a PPy/PDA concentration ratio is 30, the PPy particles are more uniformly distributed on the fiber surface. The scaffolds are wrapped in a HA coating layer with a high purity, and calcium and phosphorus elements are evenly dispersed with a Ca/P ratio being 1.69. Owing to the synergistic effect between PDA and PPy coating, the scaffolds demonstrate excellent electrochemical stability and electrochemical activity. The biological activity of the scaffold increased to 274.66% under electrical stimulation. The new thinking proposed by this study extends the worth of applying textile structure to the medical field, the application of which highly increases the prospect of bone tissue engineering.


Assuntos
Durapatita , Polímeros , Polímeros/química , Durapatita/química , Pirróis/química , Engenharia Tecidual , Tecidos Suporte/química , Condutividade Elétrica
18.
Int J Ophthalmol ; 16(9): 1456-1464, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37724274

RESUMO

AIM: To investigate the role of autophagy inhibitor 3-methyladenine (3-MA) on a diabetic mice model (DM) and the potential mechanism. METHODS: Male C57BL/6J mice were randomly divided into a normal control group (NC group) and an DM group. DM were induced by multiple low-dose intraperitoneal injection of streptozotocin (STZ) 60 mg/kg·d for 5 consecutive days. DM mice were randomly subdivided into untreated group (DM group), 3-MA (10 mg/kg·d by gavage) treated group (DM+3-MA group) and chloroquine (CQ; 50 mg/kg by intraperitoneal injection) treated group (DM+CQ group). The fasting blood glucose (FBG) levels were recorded every week. At the end of experiment, retinal samples were collected. The expression levels of pro-apoptotic proteins cleaved caspase-3, cleaved poly ADP-ribose polymerase 1 (PARP1) and Bax, anti-apoptotic protein Bcl-2, fibrosis-associated proteins Fibronectin and type 1 collagen α1 chain (COL1A1), vascular endothelial growth factor (VEGF), inflammatory factors interleukin (IL)-1ß and tumor necrosis factor (TNF)-α, as well as autophagy related proteins LC3, Beclin-1 and P62 were determined by Western blotting. The oxidative stress indicators 8-hydroxydeoxyguanosine (8-OHdG) and malondialdehyde (MDA) were detected by commercial kits. RESULTS: Both 3-MA and CQ had short-term hypoglycemic effect on FBG and reduced the expression of VEGF and inflammatory factors IL-1ß and TNF-α in DM mice. 3-MA also significantly alleviated oxidative stress indicators 8-OHdG and MDA, decreased the expression of fibrosis-related proteins Fibronectin and COL1A1, pro-apoptotic proteins cleaved caspase-3, cleaved PARP1, as well as the ratio of Bax/Bcl-2. CQ had no significant impact on the oxidative stress indicators, fibrosis, and apoptosis related proteins. The results of Western blotting for autophagy related proteins showed that the ratio of LC3 II/LC3 I and the expression of Beclin-1 in the retina of DM mice were decreased by 3-MA treatment, and the expression of P62 was further increased by CQ treatment. CONCLUSION: 3-MA has anti-apoptotic and anti-fibrotic effects on the retina of DM mice, and can attenuate retinal oxidative stress, VEGF expression and the production of inflammatory factors in the retina of DM mice. The underlying mechanism of the above effects of 3-MA may be related to its inhibition of early autophagy and hypoglycemic effect.

19.
Front Microbiol ; 14: 1252563, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37670992

RESUMO

Two novel chlorinated and nitrogenated azaphilones, namely N-butyl-2-aza-2-deoxychaetoviridin A (1) and N-hexyl-2-aza-2-deoxychaetoviridin A (2), along with a previously identified analogue, chaetoviridin A (3), were successfully obtained from Chaetomium globosum 2020HZ23, a marine algal-sourced endophytic fungus. The planar structures as well as the absolute configurations of these new metabolites were determined utilizing a synergistic approach that involved both spectroscopic techniques (1D/2D NMR and HRESIMS) and Density Functional Theory (DFT) calculations. Each compound was subject to in vitro cytotoxicity evaluation toward the A549 cancer cell line. Both compounds 1 and 2 demonstrated significant cytotoxicity, as evidenced by their respective IC50 values of 13.6 and 17.5 µM. Furthermore, 1 and 2 demonstrated potent cell migration inhibition, which elevated with increasing dose concentration. In contrast, compound 3 exhibited less cytotoxic activity relative to 1 and 2, suggesting that the cytotoxic potency escalates with N-substitution at the C-2 position and the introduction of a side chain. This finding could offer implications for future studies aimed at designing and refining lead compounds within this class.

20.
Int J Biol Macromol ; 253(Pt 3): 126737, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37689298

RESUMO

This study designed a novel co-electrospun cellulose acetate (CA)/thermoplastic polyurethane (TPU) photodynamic helical fiber antibacterial membrane as a potential environmentally friendly medical protective material. A central combined design method (CCD) based on response surface methodology (RSM) was used to analyze essential variables' influence. The optimized parameters for CCD were TPU (wt%) 11.68 %, CA (wt%) 13.89 %, DMAc/ACE volume ratio 0.147, LiCl (wt%) 1.39 %, and voltage (kV) 14.43 V. Pitch and pitch diameter were the response process as the critical output variable. The membranes were characterized by SEM, TG, FT-IR, and molecular structure analysis. The results showed that the photodynamic helical fiber antimicrobial membrane exhibited synergistic effects of the antibacterial photodynamic therapy (APDT) and antimicrobial agent under average daylight irradiation. The release rate of -OH was 98.22 %, and H2O2 was 88.36 % under the action of 20 min of light. The bactericidal rates of S. aureus and E. coli reached 99.9 % and 99.7 %, respectively. The fiber helical structure can increase the light absorption rate, thus increasing the release rate and amount of reactive oxygen species (ROS) species, increasing the antibacterial rate. After washing five times, the antibacterial membrane has excellent antibacterial performance and a dark antibacterial effect.


Assuntos
Escherichia coli , Poliuretanos , Poliuretanos/farmacologia , Poliuretanos/química , Staphylococcus aureus , Espectroscopia de Infravermelho com Transformada de Fourier , Biomimética , Peróxido de Hidrogênio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química
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