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1.
Biotechnol J ; 19(4): e2300723, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622797

RESUMO

Polyurethane (PU) is a complex polymer synthesized from polyols and isocyanates. It contains urethane bonds that resist hydrolysis, which decreases the efficiency of biodegradation. In this study, we first expressed the amidase GatA250, and then, assessed the enzymatic characterization of GatA250 and its efficiency in degrading the polyester-PU. GatA250 degraded self-synthesized thermoplastic PU film and postconsumption foam with degradation efficiency of 8.17% and 4.29%, respectively. During the degradation, the film released 14.8 µm 4,4'-methylenedianiline (MDA), but 1,4-butanediol (BDO) and adipic acid (AA) were not released. Our findings indicated that GatA250 only cleaved urethane bonds in PU, and the degradation efficiency was extremely low. Hence, we introduced the cutinase LCC, which possesses hydrolytic activity on the ester bonds in PU, and then used both enzymes simultaneously to degrade the polyester-PU. The combined system (LCC-GatA250) had higher degradation efficiency for the degradation of PU film (42.2%) and foam (13.94%). The combined system also showed a 1.80 time increase in the production of the monomer MDA, and a 1.23 and 3.62 times increase in the production of AA and BDO, respectively, compared to their production recorded after treatment with only GatA250 or LCC. This study provides valuable insights into PU pollution control and also proposes applicable solutions to manage PU wastes through bio-recycling.


Assuntos
Compostos de Anilina , Hidrolases de Éster Carboxílico , Poliésteres , Poliuretanos , Poliésteres/química , Amidoidrolases
2.
Sensors (Basel) ; 24(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38610352

RESUMO

Ultrasound is extremely efficient for wireless signal transmission through metal barriers due to no limit of the Faraday shielding effect. Echoing in the ultrasonic channel is one of the most challenging obstacles to performing high-quality communication, which is generally coped with by using a channel equalizer or pre-distorting filter. In this study, a deep learning algorithm called a dual-path recurrent neural network (DPRNN) was investigated for echo cancellation in an ultrasonic through-metal communication system. The actual system was constructed based on the combination of software and hardware, consisting of a pair of ultrasonic transducers, an FPGA module, some lab-made circuits, etc. The approach of DPRNN echo cancellation was applied to signals with a different signal-to-noise ratio (SNR) at a 2 Mbps transmission rate, achieving higher than 20 dB SNR improvement for all situations. Furthermore, this approach was successfully used for image transmission through a 50 mm thick aluminum plate, exhibiting a 24.8 dB peak-signal-to-noise ratio (PSNR) and a about 95% structural similarity index measure (SSIM). Additionally, compared with three other echo cancellation methods-LMS, RLS and PNLMS-DPRNN has demonstrated higher efficiency. All those results firmly validate that the DPRNN algorithm is a powerful tool to conduct echo cancellation and enhance the performance of ultrasonic through-metal transmission.

4.
Wei Sheng Yan Jiu ; 53(2): 243-256, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38604960

RESUMO

OBJECTIVE: To understand the prevalence, genetic characteristics and drug resistance features of Salmonella Kentucky ST314 in Shenzhen. METHODS: Whole genome sequencing of 14 strains of Salmonella Kentucky ST314 collected from 2010-2021 by the Foodborne Disease Surveillance Network of Shenzhen Center for Disease Control and Prevention for phylogenetic evolutionary analysis, drug resistance gene and plasmid detection; drug susceptibility experiments were performed by micro-broth dilution method. RESULTS: A total of 57 strains of Salmonella Kentucky were collected from the foodborne disease surveillance network, 14 of which were ST314. The Shenzhen isolates were clustered with isolates from Southeast Asian countries such as Vietnam and Thailand on clade 314.2, and the single nucleotide polymorphism distance between local strains in Shenzhen was large, indicating dissemination. In this study, a total of 17 drug resistance genes/mutations in 9 categories were detected in the genome of Salmonella Kentucky ST314, carrying 3 extended spectrum beta-lactamases(ESBLs), including bla_(CTX-M-24)(14.3%, 2/14), bla_(CTX-M-55)(7.1%, 1/14), and bla_(CTX-M-130)(14.3%, 2/14), all located on plasmids. Regarding quinolone resistance factors, two plasmid-mediated quinolone resistance(PMQR) genes were identified in the genome: qnrB6(71.4%, 10/14) and aac(6')Ib-cr(78.6%, 11/14), a quinolone resistance quinolone resistance-determining regions(QRDR) mutation T57 S(100%, 14/14). The multi-drug resistance rate of Salmonella Kentucky ST314 in Shenzhen was 92.86%(13/14)with the highest rate of resistance to tetracycline and cotrimoxazole(100%, 14/14), followed by chloramphenicol(92.86%, 13/14), cefotaxime and ampicillin(78.57%, 11/14), ciprofloxacin and nalidixic acid(71.43%, 10/14), and ampicillin-sulbactam had the lowest resistance rate(21.43%, 3/14). CONCLUSION: ST314 is the second most prevalent ST type among Salmonella Kentucky in Shenzhen, mainly isolated from food, especially poultry; phylogenetic analysis suggests that ST314 is a disseminated infection and the genome shows a highly genetically conserved phenotype. Drug resistance of Salmonella Kentucky ST314 is very serious, especially QRDR mutation, PMQR gene co-mediated quinolone resistance and plasmid-mediated cephalosporin resistance are prominent and deserve extensive attention.


Assuntos
Doenças Transmitidas por Alimentos , Quinolonas , Humanos , Kentucky , Filogenia , Salmonella , Antibacterianos/farmacologia , Plasmídeos/genética , Resistência a Medicamentos , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla/genética , beta-Lactamases/genética
5.
World J Microbiol Biotechnol ; 40(5): 160, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607448

RESUMO

ß-Carotene is an orange fat-soluble compound, which has been widely used in fields such as food, medicine and cosmetics owing to its anticancer, antioxidant and cardiovascular disease prevention properties. Currently, natural ß-carotene is mainly extracted from plants and algae, which cannot meet the growing market demand, while chemical synthesis of ß-carotene cannot satisfy the pursuit for natural products of consumers. The ß-carotene production through microbial fermentation has become a promising alternative owing to its high efficiency and environmental friendliness. With the rapid development of synthetic biology and in-depth study on the synthesis pathway of ß-carotene, microbial fermentation has shown promising applications in the ß-carotene synthesis. Accordingly, this review aims to summarize the research progress and strategies of natural carotenoid producing strain and metabolic engineering strategies in the heterologous synthesis of ß-carotene by engineered microorganisms. Moreover, it also summarizes the adoption of inexpensive carbon sources to synthesize ß-carotene as well as proposes new strategies that can further improve the ß-carotene production.


Assuntos
Produtos Biológicos , beta Caroteno , Fermentação , Carotenoides , Antioxidantes
6.
J Control Release ; 369: 556-572, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38580136

RESUMO

Vaccines represent one of the most powerful and cost-effective innovations for controlling a wide range of infectious diseases caused by various viruses and bacteria. Unlike mRNA and DNA-based vaccines, subunit vaccines carry no risk of insertional mutagenesis and can be lyophilized for convenient transportation and long-term storage. However, existing adjuvants are often associated with toxic effect and reactogenicity, necessitating expanding the repertoire of adjuvants with better biocompatibility, for instance, designing self-adjuvating polymeric carriers. We herein report a novel subunit vaccine delivery platform constructed via in situ free radical polymerization of C7A (2-(Hexamethyleneimino) ethyl methacrylate) and acrylamide around the surface of individual protein antigens. Using ovalbumin (OVA) as a model antigen, we observed substantial increases in both diameter (∼70 nm) and surface potential (-1.18 mV) following encapsulation, referred to as n(OVA)C7A. C7A's ultra pH sensitivity with a transition pH around 6.9 allows for rapid protonation in acidic environments. This property facilitates crucial processes such as endosomal escape and major histocompatibility complex (MHC)-I-mediated antigen presentation, culminating in the substantial CD8+ T cell activation. Additionally, compared to OVA nanocapsules without the C7A components and native OVA without modifications, we observed heightened B cell activation within the germinal center, along with remarkable increases in serum antibody and cytokine production. It's important to note that mounting evidence suggests that adjuvant effects, particularly its targeted stimulation of type I interferons (IFNs), can contribute to advantageous adaptive immune responses. Beyond its exceptional potency, the nanovaccine also demonstrated robust formation of immune memory and exhibited a favorable biosafety profile. These findings collectively underscore the promising potential of our nanovaccine in the realm of immunotherapy and vaccine development.

7.
Sci China Life Sci ; 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38600293

RESUMO

Association networks are widely applied for the prediction of bacterial interactions in studies of human gut microbiomes. However, the experimental validation of the predicted interactions is challenging due to the complexity of gut microbiomes and the limited number of cultivated bacteria. In this study, we addressed this challenge by integrating in vitro time series network (TSN) associations and co-cultivation of TSN taxon pairs. Fecal samples were collected and used for cultivation and enrichment of gut microbiome on YCFA agar plates for 13 days. Enriched cells were harvested for DNA extraction and metagenomic sequencing. A total of 198 metagenome-assembled genomes (MAGs) were recovered. Temporal dynamics of bacteria growing on the YCFA agar were used to infer microbial association networks. To experimentally validate the interactions of taxon pairs in networks, we selected 24 and 19 bacterial strains from this study and from the previously established human gut microbial biobank, respectively, for pairwise co-cultures. The co-culture experiments revealed that most of the interactions between taxa in networks were identified as neutralism (51.67%), followed by commensalism (21.67%), amensalism (18.33%), competition (5%) and exploitation (3.33%). Genome-centric analysis further revealed that the commensal gut bacteria (helpers and beneficiaries) might interact with each other via the exchanges of amino acids with high biosynthetic costs, short-chain fatty acids, and/or vitamins. We also validated 12 beneficiaries by adding 16 additives into the basic YCFA medium and found that the growth of 66.7% of these strains was significantly promoted. This approach provides new insights into the gut microbiome complexity and microbial interactions in association networks. Our work highlights that the positive relationships in gut microbial communities tend to be overestimated, and that amino acids, short-chain fatty acids, and vitamins are contributed to the positive relationships.

8.
Nicotine Tob Res ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602278

RESUMO

INTRODUCTION: Cigarette smoking greatly promotes the progression and poor prognosis of colorectal cancer (CRC) patients, with the molecular mechanism still not fully clear. METHODS: In this study, CRC cells were exposed to tobacco specific nitrosamine 4­(methylnitrosamino)­1­(3­pyridyl) 1­butanone (NNK), and the differentially expressed smoking-related genes were identified based on both NNK-induced CRC cells and a total of 763 CRC tissues from TCGA cohort. Cox regression analysis, ROC curve and Kaplan-Meier plot were used to establish the risk score model for CRC prognosis. Moreover, qRT-PCR, western blotting, colony formation, migration and invasion assays were performed to verify the core differentially expressed smoking-related gene and its molecular function in NNK-induced CRC progression. RESULTS: Results indicated NNK significantly enhanced CRC cell proliferation, migration and invasion. Moreover, a four-gene signature containing AKR1B10, CALB2, PLAC1, GNA15 was established as CRC prognosis marker. Among these four genes, AKR1B10 was further validated as the core gene, and its expression was significantly inhibited after NNK exposure in CRC cells. Results of gene enrichment analysis and western blotting suggested AKR1B10 might reduce the malignant progression of NNK-induced CRC cells through inhibiting Wnt signaling pathway by promoting E-Cadherin expression and inhibiting the expression of N-Cadherin, ß-Catenin, Vimentin and Snail. CONCLUSION: In conclusion, a new four smoking-related genes can be jointly used as prognostic markers for CRC. AKR1B10 served as a tumor suppressor, can be used as a potential target to inhibit NNK-induced CRC malignant progression through regulating Wnt signaling pathway. IMPLICATIONS: This study demonstrates tobacco-derived NNK dependence would promote the malignant progression of colorectal cancer through regulating the expressions of AKR1B10/Wnt signaling pathway. And a novel four-gene signature is established for the prognosis prediction of smoking CRC patients. These findings have important translational implications given the continued use of tobacco and the difficulty in smoking cessation worldwide, which can be applied to alleviate the adverse effects induced by tobacco dependence on colorectal cancer patients.

9.
J Inflamm Res ; 17: 2023-2037, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577691

RESUMO

Background: Inflammatory bowel disease (IBD) is a chronic recurrent gastrointestinal inflammatory disease. Selenium has been reported to have therapeutic potential in IBD. Selenium yeast is a common selenium supplement that is convenient to access. This study explored the effect of selenium yeast on dextran sulfate sodium- (DSS-)induced chronic colitis in mice. Methods: Mice were randomly divided into four groups: the control group, selenium yeast group, chronic colitis group, and chronic colitis+selenium yeast group (n=6). Mice were killed on the 26th day. The disease activity index (DAI) score and histological damage score were calculated. Cytokines, serum selenium, colonic tissue selenium, gut microbiota and their metabolites short-chain fatty acids (SCFAs) were evaluated. Results: Selenium yeast lowered IL-1ß, IL-6, TNF-α, IL-17A, IL-22 and IFN-γ (P<0.05). In addition, selenium yeast significantly elevated Turicibacter, Bifidobacterium, Allobaculum, Prevotella, Halomonas, Adlercreutzia (P<0.05), and butyric acid (P<0.05). Conclusion: Selenium yeast could improve DSS-induced chronic colitis in mice by regulating cytokines, gut microbiota and their metabolites.

10.
Crit Rev Biotechnol ; : 1-17, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503543

RESUMO

As an important cell factory, industrial yeast has been widely used for the production of compounds ranging from bulk chemicals to complex natural products. However, various adverse conditions including toxic products, extreme pH, and hyperosmosis etc., severely restrict microbial growth and metabolic performance, limiting the fermentation efficiency and diminishing its competitiveness. Therefore, enhancing the tolerance and robustness of yeasts is critical to ensure reliable and sustainable production of metabolites in complex industrial production processes. In this review, we provide a comprehensive review of various strategies for improving the tolerance of yeast cells, including random mutagenesis, system metabolic engineering, and material-mediated immobilization cell technology. It is expected that this review will provide a new perspective to realize the response and intelligent regulation of yeast cells to environmental stresses.

11.
Front Cardiovasc Med ; 11: 1352515, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38433756

RESUMO

Objective: This study aims to explore the effects of the Information-Motivation-Behavioral (IMB) Skills Model on the prevention of Venous Thromboembolism (VTE) in elderly lung cancer patients. Methods: A convenience sampling method was used to select study participants who were hospitalized for treatment between November 2022 and August 2023 at a tertiary hospital in Neijiang and met the inclusion and exclusion criteria. The control group (n = 41) received conventional health education, while the intervention group (n = 40) received health education based on the IMB Skills Model over three months. The scores of the Venous Thrombosis Knowledge, Participation in Thrombosis Prevention Willingness and Behavior Questionnaire, and Quality of Life Measurement Scale (QLQ-C30) were compared before the intervention and after three months. After three months of intervention, the hospital satisfaction and VTE incidence rates in both groups were investigated and compared. Results: After three months of intervention, the scores for the Venous Thrombosis Knowledge, (Participation in Thrombosis Prevention Willingness and Behavior Questionnaire in the intervention group were higher than those in the control group (P < 0.05). The QLQ-C30 scores in the intervention group for physical function, role function, emotional function, insomnia, appetite loss, and overall health status were higher than those in the control group (P < 0.05). The intervention group rated higher in doctor's professional skills, information provision, accessibility; nurse's professional skills, humanistic care, information provision, accessibility; team communication, services of other personnel, overall satisfaction compared to the control group (P < 0.05). The rate of VTE in the intervention group was 2.5%(1/40), and that in the control group was 19.5%(8/41). There was a significant difference (χ2 = 4.336, P = 0.037). Conclusion: Nursing interventions based on the IMB Skills Model for elderly lung cancer patients can enhance patients' understanding of venous thrombosis, increase willingness and active participation in thrombosis prevention, improve quality of life, increase hospital satisfaction, and reduce the incidence of VTE.

12.
Exp Ther Med ; 27(5): 179, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38515649

RESUMO

[This retracts the article DOI: 10.3892/etm.2018.5714.].

13.
World J Gastroenterol ; 30(8): 956-968, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38516245

RESUMO

BACKGROUND: The prevalence of sarcopenia in patients undergoing liver transplantation (LT) remains to be determined partly because of different diagnostic criteria. Sarcopenia has recently been recognized as a new prognostic factor for predicting outcomes in LT candidates. AIM: To estimate the prevalence of sarcopenia and evaluate its clinical effect on LT candidates. METHODS: This systematic search was conducted in PubMed, Web of Science, Embase, and Cochrane Library for original English-language articles that investigated the prevalence and influence of sarcopenia in patients undergoing LT from database inception to November 30, 2022. Cohort studies of the definition of sarcopenia that estimate sarcopenia prevalence and evaluate its effect on clinical outcomes and the risk of mortality were included. RESULTS: Twenty-five studies involving 7760 patients undergoing LT were included. The pooled prevalence of sarcopenia in patients undergoing LT was 40.7% [95% confidence intervals (95%CI): 32.1-49.6]. The 1-, 3-, and 5-year cumulative probabilities of post-LT survival in patients with preoperative sarcopenia were all lower than those without sarcopenia (P < 0.05). Sarcopenia was associated with an increased risk of post-LT mortality in patients undergoing LT (adjusted hazard ratio: 1.58; 95%CI: 1.21-2.07). Patients with preoperative sarcopenia had a longer intensive care unit stay, a high risk ratio of sepsis, and serious post-LT complications than those without sarcopenia. CONCLUSION: Sarcopenia is prevalent in a substantial proportion of patients undergoing LT and is strongly and independently associated with higher a risk of mortality risk.


Assuntos
Transplante de Fígado , Sarcopenia , Humanos , Sarcopenia/etiologia , Transplante de Fígado/efeitos adversos , Prevalência , Razão de Chances , Probabilidade
14.
Appl Environ Microbiol ; 90(4): e0147723, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38445906

RESUMO

Plastic degradation by biological systems emerges as a prospective avenue for addressing the pressing global concern of plastic waste accumulation. The intricate chemical compositions and diverse structural facets inherent to polyurethanes (PU) substantially increase the complexity associated with PU waste management. Despite the extensive research endeavors spanning over decades, most known enzymes exhibit a propensity for hydrolyzing waterborne PU dispersion (i.e., the commercial Impranil DLN-SD), with only a limited capacity for the degradation of bulky PU materials. Here, we report a novel cutinase (CpCut1) derived from Cladosporium sp. P7, which demonstrates remarkable efficiency in the degrading of various polyester-PU materials. After 12-h incubation at 55°C, CpCut1 was capable of degrading 40.5% and 20.6% of thermoplastic PU film and post-consumer foam, respectively, while achieving complete depolymerization of Impranil DLN-SD. Further analysis of the degradation intermediates suggested that the activity of CpCut1 primarily targeted the ester bonds within the PU soft segments. The versatile performance of CpCut1 against a spectrum of polyester-PU materials positions it as a promising candidate for the bio-recycling of waste plastics.IMPORTANCEPolyurethane (PU) has a complex chemical composition that frequently incorporates a variety of additives, which poses significant obstacles to biodegradability and recyclability. Recent advances have unveiled microbial degradation and enzymatic depolymerization as promising waste PU disposal strategies. In this study, we identified a gene encoding a cutinase from the PU-degrading fungus Cladosporium sp. P7, which allowed the expression, purification, and characterization of the recombinant enzyme CpCut1. Furthermore, this study identified the products derived from the CpCut1 catalyzed PU degradation and proposed its underlying mechanism. These findings highlight the potential of this newly discovered fungal cutinase as a remarkably efficient tool in the degradation of PU materials.


Assuntos
Hidrolases de Éster Carboxílico , Cladosporium , Poliuretanos , Poliuretanos/química , Poliuretanos/metabolismo , Cladosporium/genética , Cladosporium/metabolismo , Estudos Prospectivos , Biodegradação Ambiental , Poliésteres/metabolismo , Plásticos
15.
Chin Med ; 19(1): 37, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429848

RESUMO

BACKGROUND: Osteoarthritis (OA) is a prevalent global health concern associated with the loss of articular cartilage and subchondral bone. The lack of disease-modifying drugs for OA necessitates the exploration of novel therapeutic options. Our previous study has demonstrated that traditional Chinese medical herb Trachelospermum jasminoides (Lindl.) Lem. extract suppressed osteoclastogenesis and identified trachelogenin (TCG) as a representative compound. Here, we delved into TCG's potential to alleviate OA. METHODS: We initially validated the in vivo efficacy of TCG in alleviating OA using a rat OA model. Subsequently, we isolated primary bone marrow-derived macrophages in vitro to investigate TCG's impact on osteoclastogenesis. We further employed a small molecule pull-down assay to verify TCG's binding target within osteoclasts. Finally, we isolated primary mouse chondrocytes in vitro to study TCG's regulatory effects and mechanisms on chondrocyte survival. RESULTS: TCG preserved subchondral bone integrity and protected articular cartilage in a rat OA model. Subsequently, in vitro experiments unveiled TCG's capability to inhibit osteoclastogenesis and function through binding to Ras association proximate 1 (Rap1) and inhibiting its activation. Further study demonstrated that TCG inhibited Rap1/integrin αvß3/c-Src/Pyk2 signaling cascade, and consequently led to failed F-actin ring formation. Besides, TCG promoted the proliferation of mouse primary chondrocytes while suppressing apoptosis in vitro. This is attributed to TCG's ability to upregulate HIF1α, thereby promoting glycolysis. CONCLUSION: TCG exerted inhibitory effects on osteoclastogenesis through binding to Rap1 and inhibiting Rap1 activation, consequently preventing subchondral bone loss. Moreover, TCG enhanced chondrocyte survival by upregulating HIF1α and promoting glycolysis. These dual mechanisms collectively provide a novel approach to prevented against cartilage degradation.

16.
Front Microbiol ; 15: 1301073, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440147

RESUMO

Introduction: Gut microbes form complex networks that significantly influence host health and disease treatment. Interventions with the probiotic bacteria on the gut microbiota have been demonstrated to improve host well-being. As a representative of next-generation probiotics, Christensenella minuta (C. minuta) plays a critical role in regulating energy balance and metabolic homeostasis in human bodies, showing potential in treating metabolic disorders and reducing inflammation. However, interactions of C. minuta with the members of the networked gut microbiota have rarely been explored. Methods: In this study, we investigated the impact of C. minuta on fecal microbiota via metagenomic sequencing, focusing on retrieving bacterial strains and coculture assays of C. minuta with associated microbial partners. Results: Our results showed that C. minuta intervention significantly reduced the diversity of fecal microorganisms, but specifically enhanced some groups of bacteria, such as Lactobacillaceae. C. minuta selectively enriched bacterial pathways that compensated for its metabolic defects on vitamin B1, B12, serine, and glutamate synthesis. Meanwhile, C. minuta cross-feeds Faecalibacterium prausnitzii and other bacteria via the production of arginine, branched-chain amino acids, fumaric acids and short-chain fatty acids (SCFAs), such as acetic. Both metagenomic data analysis and culture experiments revealed that C. minuta negatively correlated with Klebsiella pneumoniae and 14 other bacterial taxa, while positively correlated with F. prausnitzii. Our results advance our comprehension of C. minuta's in modulating the gut microbial network. Conclusions: C. minuta disrupts the composition of the fecal microbiota. This disturbance is manifested through cross-feeding, nutritional competition, and supplementation of its own metabolic deficiencies, resulting in the specific enrichment or inhibition of the growth of certain bacteria. This study will shed light on the application of C. minuta as a probiotic for effective interventions on gut microbiomes and improvement of host health.

17.
ACS Nano ; 18(11): 7945-7958, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38452275

RESUMO

Ferroptosis is a form of regulated cell death accompanied by lipid reactive oxygen species (ROS) accumulation in an iron-dependent manner. However, the efficiency of tumorous ferroptosis was seriously restricted by intracellular ferroptosis defense systems, the glutathione peroxidase 4 (GPX4) system, and the ubiquinol (CoQH2) system. Inspired by the crucial role of mitochondria in the ferroptosis process, we reported a prodrug nanoassembly capable of unleashing potent mitochondrial lipid peroxidation and ferroptotic cell death. Dihydroorotate dehydrogenase (DHODH) inhibitor (QA) was combined with triphenylphosphonium moiety through a disulfide-containing linker to engineer well-defined nanoassemblies (QSSP) within a single-molecular framework. After being trapped in cancer cells, the acidic condition provoked the structural disassembly of QSSP to liberate free prodrug molecules. The mitochondrial membrane-potential-driven accumulation of the lipophilic cation prodrug was delivered explicitly into the mitochondria. Afterward, the thiol-disulfide exchange would occur accompanied by downregulation of reduced glutathione levels, thus resulting in mitochondria-localized GPX4 inactivation for ferroptosis. Simultaneously, the released QA from the hydrolysis reaction of the adjacent ester bond could further devastate mitochondrial defense and evoke robust ferroptosis via the DHODH-CoQH2 system. This subcellular targeted nanoassembly provides a reference for designing ferroptosis-based strategy for efficient cancer therapy through interfering antiferroptosis systems.


Assuntos
Ferroptose , Compostos Organofosforados , Pró-Fármacos , Pró-Fármacos/farmacologia , Pró-Fármacos/metabolismo , Di-Hidro-Orotato Desidrogenase , Peroxidação de Lipídeos , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Dissulfetos/metabolismo
18.
Angew Chem Int Ed Engl ; : e202403424, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38545934

RESUMO

Rechargeable aluminum batteries (RABs) are a promising candidate for large-scale energy storage, attributing to the abundant reserves, low cost, intrinsic safety, and high theoretical capacity of Al. However, the cathode materials reported thus far still face challenges such as limited capacity, sluggish kinetics, and undesirable cycle life. Herein, we propose an organic cathode benzo[i] benzo[6,7] quinoxalino [2,3-a] benzo [6,7] quinoxalino [2,3-c] phenazine-5,8,13,16,21,24-hexaone (BQQPH) for RABs. The six C=O and six C=N redox active sites in each molecule enable BQQPH to deliver a record ultra-high capacity of 413 mAh g-1 at 0.2 A g-1. Encouragingly, the intermolecular hydrogen bonding network and π-π stacking interactions endow BQQPH with robust structural stability and minimal solubility, enabling an ultra-long lifetime of 100,000 cycles. Moreover, the electron-withdrawing carbonyl group induces a reduction in the energy level of the lowest unoccupied molecular orbital and expands the π-conjugated system, which considerably enhances both the discharge voltage and redox kinetics of BQQPH. In-situ and ex-situ characterizations combined with theoretical calculations unveil that the charge storage mechanism is reversible coordination/dissociation of AlCl2+ with the N and O sites in BQQPH accompanied by 12-electron transfer. This work provides valuable insights into the design of high-performance organic cathode materials for RABs.

19.
CNS Neurosci Ther ; 30(3): e14694, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38532579

RESUMO

BACKGROUND: Intracerebral hemorrhage (ICH) is a common cerebrovascular disease, and the complement cascade exacerbates brain injury after ICH. As the most abundant component of the complement system, complement component 3 (C3) plays essential roles in all three complement pathways. However, the effects of C3 on neurological impairment and brain injury in ICH patients and the related mechanism have not been fully elucidated. Normobaric hyperoxia (NBO) is regarded as a treatment for ICH patients, and recent clinical studies also have confirmed the neuroprotective role of NBO against acute ICH-mediated brain damage, but the underlying mechanism still remains elusive. AIMS: In the present study, we investigated the effects of complement C3 on NBO-treated ICH patients and model mice, and the underlying mechanism of NBO therapy in ICH-mediated brain injury. RESULTS: Hemorrhagic injury resulted in the high plasma C3 levels in ICH patients, and the plasma C3 levels were closely related to hemorrhagic severity and clinical outcomes after ICH. BO treatment alleviated neurologic impairments and rescued the hemorrhagic-induced increase in plasma C3 levels in ICH patients and model mice. Moreover, the results indicated that NBO exerted its protective effects of on brain injury after ICH by downregulating the expression of C3 in microglia and alleviating microglia-mediated synaptic pruning. CONCLUSIONS: Our results revealed that NBO exerts its neuroprotective effects by reducing C3-mediated synaptic pruning, which suggested that NBO therapy could be used for the clinical treatment of ICH.


Assuntos
Lesões Encefálicas , Hiperóxia , Humanos , Camundongos , Animais , Complemento C3/metabolismo , Complemento C3/uso terapêutico , Hemorragia Cerebral/metabolismo , Hemorragias Intracranianas
20.
Mater Today Bio ; 25: 101011, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38445010

RESUMO

Bone defects caused by trauma, tumor resection, or developmental abnormalities are important issues in clinical practice. The vigorous development of tissue engineering technology provides new ideas and directions for regenerating bone defects. Hydroxyapatite (HAp), a bioactive ceramic, is extensively used in bone tissue engineering because of its excellent osteoinductive performance. However, its application is challenged by its single function and conventional environment-unfriendly synthesis methods. In this study, we successfully "green" synthesized sr-silk fibroin co-assembly hydroxyapatite nanoparticles (Sr-SF-HA) using silk fibroin (SF) as a biomineralized template, thus enabling it to have angiogenic activity and achieving the combination of organic and inorganic substances. Then, the rough composite microspheres loaded with Sr-SF-HA (CS/Sr-SF-HA) through electrostatic spraying technology and freeze-drying method were prepared. The CCK-8 test and live/dead cell staining showed excellent biocompatibility of CS/Sr-SF-HA. Alkaline phosphatase (ALP) staining, alizarin red staining (ARS), immunofluorescence, western blotting, and qRT-PCR test showed that CS/Sr-SF-HA activated the expression of related genes and proteins, thus inducing the osteogenic differentiation of rBMSCs. Moreover, tube formation experiments, scratch experiments, immunofluorescence, and qRT-PCR detection indicated that CS/Sr-SF-HA have good angiogenic activity. Furthermore, in vivo studies showed that the CS/Sr-SF-HA possesses excellent biocompatibility, vascular activity, as well as ectopic osteogenic ability in the subcutaneous pocket of rats. This study indicates that the construction of CS/Sr-SF-HA with angiogenic and osteogenic properties has great potential for bone tissue engineering.

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