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1.
Int J Biol Macromol ; 277(Pt 4): 134562, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39116982

RESUMO

Antifreeze proteins (AFPs) can inhibit ice crystal growth. The ice-binding mechanism of AFPs remains unclear, yet the hydration shells of AFPs are thought to play an important role in modulating the binding of AFPs and ice. Here, we performed all-atom molecular dynamics simulations of an AFP from Choristoneura fumiferana (CfAFP) at four different temperatures, with a focus on analysis at 240 and 300 K, to investigate the dynamic and thermodynamic characteristics of hydration shells around ice-binding surfaces (IBS) and non-ice-binding surfaces (NIBS). Our results revealed that the dynamics of CfAFP hydration shells were highly heterogeneous, with its IBS favoring a less dense and more tetrahedral solvation shell, and NIBS hydration shells having opposite features to those of the IBS. The IBS of nine typical hyperactive AFPs were found to be in pure low-entropy hydration shell region, indicating that low-entropy hydration shell region of IBS and the tetrahedral arrangements of water molecules around them mediate the ice-binding mechanism of AFPs. It is because the entropy increase of the low-entropy hydration shell around IBS, while the higher entropy water molecules at NIBS most likely prevent ice crystal growth. These findings provide new mechanistic insights into the ice-binding of AFPs.

2.
Nat Commun ; 15(1): 6973, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143058

RESUMO

Mechanochemistry studies the effect of mechanical force on chemical bonds, bringing opportunities for synthesizing alloys, ceramics, organics, polymers, and biomaterials. A vital issue of applying macro-scale mechanical force to manipulate crystal structures is finding ways to precisely adjust the force directions to break micro-scale target chemical bonds. Inspired by a common technique of driving a wedge into the wood to make wood chopping much easier, a wedging strategy of splitting three-dimensional structured crystalline frameworks and then converting them to nanosheets was proposed, where specific molecules were wedged into crystalline frameworks to drive the directional transmission of mechanical force to break chemical bonds. As a result, various crystalline framework nanosheets including metal-organic framework nanosheets, covalent organic framework nanosheets, and coordination polymer nanosheets were fabricated. This wedging crystal strategy exhibits advantages of operability, flexibility and designability, and furthermore, it is expected to expand mechanochemistry applications in material preparation.

3.
Food Chem ; 459: 140345, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38986204

RESUMO

Considering the high abundance of bound polyphenols (BP) in whole grain dietary fiber (DF), this study utilized multi-omics approach to evaluate the impact of BP of defatted rice bran insoluble DF (RIDF) in modulating obesity. Mice on high-fat diet were gavage-administered RIDF, BP-removed or formulated RIDF. The results indicated that DF significantly reduced serum total cholesterol, triglycerides, high-density and low-density lipoprotein cholesterol levels. Moreover, hepatic lipid accumulation and damage induced by high-fat diet were significantly ameliorated with DF intervention. The presence of BP increased the abundance of beneficial bacteria g_Akkermansia and g_Butyricicocus, as well as the expression of butyric acid/propionic acid. Furthermore, the expression of hepatic lipids and lipid-like molecules was significantly decreased under the combined intervention of BP and DF, and this was accompanied by alterations in genes related to lipid, sterol, and cholesterol metabolic biological processes. These findings suggest that BP contribute to the anti-obesity effects of DF.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39004908

RESUMO

BACKGROUND: Prostate cancer is an adverse tumor that occurs in the male reproductive system. The symptoms of patients in the early stage are not obvious and are generally difficult to detect. AIM: The aim of this study was to determine the regulation of lncRNA GABPB1-AS1 (GABPB1-AS1) on prostate cancer progression and explore the diagnostic potential of GABPB1-AS1. METHODS: The contents of serum GABPB1-AS1 and miR-330-3p were examined by RT-qPCR assay. The functions of silencing GABPB1-AS1 and miR-330-3p inhibitor in prostate cancer cells were determined using transfection assay, CCK-8 assay and Transwell assay. The target of GABPB1-AS1 was predicted and verified at the molecular level by bioinformatics and luciferase reporter gene assay. The function of GABPB1-AS1 in prostate cancer diagnosis was evaluated via ROC method. RESULTS: GABPB1-AS1 was upregulated in prostate cancer serum, which was associated with patients' Gleason score and TNM stage. Mechanistically, GABPB1-AS1 directly targeted miR-330-3p, and there was a negative correlation between them. Reduced levels of GABPB1-AS1 in cells after knockdown of GABPB1-AS1 resulted in decreased prostate cancer cell growth and activity, and these inhibitory effects were repaired by miR-330-3p inhibitor. CONCLUSION: The present study confirmed that GABPB1-AS1 was overexpressed in prostate cancer, and its sponge miR-330-3p may be an effective target for timely diagnosis of prostate cancer.

5.
Neural Netw ; 178: 106491, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38972131

RESUMO

In this paper, we propose a novel two-layer fuzzy neural network model (TLFNN) for solving the inequality-constrained ℓ1-minimization problem. The stability and global convergence of the proposed TLFNN model are detailedly analyzed using the Lyapunov theory. Compared with the existing three-layer neural network model (TLNN) recently designed by Yang et al., the proposed TLFNN model possesses less storage, stronger robustness, faster convergence rate and higher convergence accuracy. These advantages are illustrated by some numerical experiments, where it is shown that the TLFNN model can achieve a convergence accuracy of 10-13 within 5s while the TLNN model can only acquire 10-6 in 105s when some random coefficient matrices are applied. Since the linear equality-constrained conditions can be equivalently transformed into double inequality-constrained ones, some simulation experiments for sparse signal reconstruction show that the proposed TLFNN model also has less convergence time and stronger robustness than the existing state-of-the-art neural network models for the equality-constrained ℓ1-minimization problem.


Assuntos
Lógica Fuzzy , Redes Neurais de Computação , Algoritmos , Simulação por Computador , Humanos
6.
Huan Jing Ke Xue ; 45(7): 3919-3929, 2024 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-39022940

RESUMO

Organophosphates (OPEs) are widely used as flame retardants and additives and thus are commonly detected in the environment. In order to explore their environmental behavior, the concentrations of 13 OPEs in the surface water and sediment of Dongting Lake were analyzed using UPLC-MS/MS. The results showed that 11 OPEs were detected, with detection frequencies of 5.26%-100% and 58.3%-100%, and the concentrations of OPEs were 2.06-2 028 ng·L-1 and 19.6-2 232 ng·g-1 in water and sediment, respectively. Overall, contamination concentrations were ranked in descending order as follows: inflowing rivers, lake area, and outlet, whereas the spatial distribution of concentrations in sediment was inversely proportional to hydrodynamics. The concentration of OPEs in Dongting Lake was at a high level compared with that of domestic and foreign lakes. Among the detected 11 OPEs, tri-iso-butyl phosphate (TnBP) and (TiBP) were dominant in water, accounting for 52.3% and 22.4% of ∑OPEs, respectively. TPhP was the dominant OPEs in sediment, accounting for 31.2% of ∑OPEs. The correlation and principal component analysis indicated that OPEs pollution in Dongting Lake was mainly affected by industrial production emissions, fishery aquaculture, and atmospheric deposition. The assessment results of the risk entropy showed that most of the detected OPEs in water had relatively low ecological risks, whereas the ecological risk of 2-ethylhexyl diphenyl phosphate (EHDPP) at some sampling points requires further attention.

7.
Food Res Int ; 189: 114535, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876588

RESUMO

The impact of different forms of dietary fiber (total, insoluble or soluble) derived from the same source on health remains incompletely understood. In this study, the effects of total, insoluble, and soluble dietary fiber extracted from highland barley (HDF, HIDF, and HSDF) on combating obesity were evaluated and compared. A high-fat diet (HFD) was used to induce obesity in a murine model, followed by gavage administration of HDF, HIDF, or HSDF, and a comprehensive multi-omics approach was utilized to assess and compare the effects of these dietary fibers on obesity-related parameters. The results showed that all three dietary fibers significantly reduced body weight, modified blood lipid profiles, and ameliorated tissue damage in HFD-fed mice. Additionally, 16S rRNA sequencing analysis of mice feces showed that three types of dietary fiber exerted varying degrees of impact on the composition and abundance of gut microbiota while simultaneously promoting the biosynthesis of short-chain fatty acids. Specifically, HDF supplementation remarkably enhanced the abundance of Coprococcus, while HIDF and HSDF supplementation elevated the levels of Akkermansia and Allobaculum, respectively. Transcriptomic and proteomic results suggested the PPAR signaling pathway as a central regulatory mechanism influenced by these fibers. HDF and HIDF were particularly effective in modulating biological processes related to triglyceride and fatty acid metabolism, identifying Abcc3 and Dapk1 as potential targets. Conversely, HSDF primarily affected processes related to membrane lipids, ceramides, and phospholipids metabolism, with Pck1 identified as a potential target. Collectively, HDF, HIDF, and HSDF demonstrated distinct mechanisms in exerting exceptional anti-obesity properties. These insights may inform the development of personalized dietary interventions for obesity.


Assuntos
Fármacos Antiobesidade , Dieta Hiperlipídica , Fibras na Dieta , Microbioma Gastrointestinal , Hordeum , Camundongos Endogâmicos C57BL , Obesidade , Hordeum/química , Fibras na Dieta/farmacologia , Animais , Camundongos , Masculino , Fármacos Antiobesidade/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Proteômica , Modelos Animais de Doenças , Multiômica
8.
J Agric Food Chem ; 72(25): 14315-14325, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38847877

RESUMO

This study aimed to investigate the mitigation effect of epigallocatechin gallate (EGCG) on aging induced by 3-monochloropropane-1,2-diol (3-MCPD) in Caenorhabditis elegans, evaluate health indicators during the process, and reveal the underlying mechanism through transcriptomics and identification of mutants. The results showed that EGCG alleviated the declined fertility, shortened lifespan, reduced body size, weakened movement, increased reactive oxygen species and lipofuscin, and damaged antioxidative stress response and excessive heat shock proteins caused by 3-MCPD. Transcriptomics study indicated that treatment with 3-MCPD and EGCG altered gene expression, and gene mutants confirmed the involvement of insulin/IGF-1 signaling pathway in mediating the process that EGCG alleviated the aging toxicity induced by 3-MCPD. The study showed that EGCG alleviated the aging toxicity induced by 3-MCPD.


Assuntos
Envelhecimento , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Catequina , Proteínas de Choque Térmico , Reprodução , alfa-Cloridrina , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Catequina/análogos & derivados , Catequina/farmacologia , Reprodução/efeitos dos fármacos , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Envelhecimento/efeitos dos fármacos , alfa-Cloridrina/toxicidade , Transdução de Sinais/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Longevidade/efeitos dos fármacos
9.
ACS Appl Mater Interfaces ; 16(27): 35024-35032, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38935758

RESUMO

Inorganic metal sulfides have received extensive investigation as anode materials in lithium-ion batteries (LIBs). However, applications of crystalline organic hybrid metal sulfides as anode materials in LIBs are quite rare. In addition, combining the nanoparticles of crystalline organic hybrid metal sulfides with conductive materials is expected to enhance the electrochemical lithium storage performance. Nevertheless, due to the difficulty of harvesting the nanoparticles of crystalline organic hybrid metal sulfides, this approach has never been tried to date. Herein, nanoparticles of a crystalline organic hybrid cadmium antimony sulfide (1,4-DABH2)Cd2Sb2S6 (DCAS) were prepared by a top-down method, including the procedures of solvothermal synthesis, ball milling, and ultrasonic pulverization. Thereafter, the nanoparticles of DCAS with sizes of ∼500 nm were intercalated into graphene oxide nanosheets through a freeze-drying treatment and a DCAS@GO composite was obtained. Compared with the reported Sb2S3- and CdS-based composites, the DCAS@GO composite exhibited superior electrochemical Li+ ion storage performance, including a high capacity of 1075.6 mAh g-1 at 100 mA g-1 and exceptional rate tolerances (646.8 mAh g-1 at 5000 mA g-1). In addition, DCAS@GO can provide a high capacity of 705.6 mAh g-1 after 500 cycles at 1000 mA g-1. Our research offers a viable approach for preparing the nanoparticles of crystalline organic hybrid metal sulfides and proves that intercalating organic hybrid metal sulfide nanoparticles into GO nanosheets can efficiently boost the electrochemical Li+ ion storage performance.

10.
Org Lett ; 26(21): 4526-4531, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38761124

RESUMO

We report a novel organic photoredox catalysis to achieve unprecedented γ-(hetero)aryl/alkenyl-δ-silyl aliphatic amines via silyl-mediated distal (hetero)aryl/alkenyl migration of aromatic/alkenyl amines bearing unactivated alkenes with hydrosilanes. This protocol features mild and metal-free reaction conditions, high atom economy, excellent selectivity, and functional group compatibility. Mechanistic studies suggest that silylation and (hetero)aryl/alkenylation involve photoredox hydrogen atom transfer catalysis and subsequent 1,4-migration of a remote (hetero)aryl/alkenyl group from nitrogen to carbon.

11.
Int J Biol Macromol ; 270(Pt 1): 132066, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705323

RESUMO

A comprehensive multiscale analysis was conducted to explore the effects of different ratios of these materials on its properties. The results show that KC played a crucial role in controlling solution viscosity and gel and sol temperatures. The dissolution time at high water temperatures primarily decreased with an increase in SA content. Higher KC and CS content increased tensile strength (TS) and elongation at break (ε), while also exhibiting better thermal stability. Water vapor transmission (WVT) and permeability (PV) initially decreased, then increased with the increase of SA and CS contents. Finally, an SA:KC:CS ratio of 1:3:2 showed optimal comprehensive properties, with a dissolution time of about 60.0 ± 3.8 s, TS of 23.80 ± 0.29 MPa, ε of 18.61 ± 0.34 %, WVT of 21.74 ± 0.62 g/m2·24h, and PV of 5.39 ± 0.17 meq/kg. Meanwhile, the SA:KC:CS edible food packaging only introduced minimal effects on food after dissolution, and the total bacterial count met regulatory standards.


Assuntos
Filmes Comestíveis , Embalagem de Alimentos , Permeabilidade , Água , Embalagem de Alimentos/métodos , Água/química , Polissacarídeos/química , Solubilidade , Temperatura Alta , Viscosidade , Resistência à Tração , Vapor , Fenômenos Mecânicos , Fast Foods/análise
12.
BMC Cancer ; 24(1): 549, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693523

RESUMO

BACKGROUND: Accurate assessment of axillary status after neoadjuvant therapy for breast cancer patients with axillary lymph node metastasis is important for the selection of appropriate subsequent axillary treatment decisions. Our objectives were to accurately predict whether the breast cancer patients with axillary lymph node metastases could achieve axillary pathological complete response (pCR). METHODS: We collected imaging data to extract longitudinal CT image features before and after neoadjuvant chemotherapy (NAC), analyzed the correlation between radiomics and clinicopathological features, and developed models to predict whether patients with axillary lymph node metastasis can achieve axillary pCR after NAC. The clinical utility of the models was determined via decision curve analysis (DCA). Subgroup analyses were also performed. Then, a nomogram was developed based on the model with the best predictive efficiency and clinical utility and was validated using the calibration plots. RESULTS: A total of 549 breast cancer patients with metastasized axillary lymph nodes were enrolled in this study. 42 independent radiomics features were selected from LASSO regression to construct a logistic regression model with clinicopathological features (LR radiomics-clinical combined model). The AUC of the LR radiomics-clinical combined model prediction performance was 0.861 in the training set and 0.891 in the testing set. For the HR + /HER2 - , HER2 + , and Triple negative subtype, the LR radiomics-clinical combined model yields the best prediction AUCs of 0.756, 0.812, and 0.928 in training sets, and AUCs of 0.757, 0.777 and 0.838 in testing sets, respectively. CONCLUSIONS: The combination of radiomics features and clinicopathological characteristics can effectively predict axillary pCR status in NAC breast cancer patients.


Assuntos
Axila , Neoplasias da Mama , Linfonodos , Metástase Linfática , Terapia Neoadjuvante , Nomogramas , Tomografia Computadorizada por Raios X , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Metástase Linfática/diagnóstico por imagem , Pessoa de Meia-Idade , Linfonodos/patologia , Linfonodos/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Terapia Neoadjuvante/métodos , Adulto , Idoso , Estudos Retrospectivos , Radiômica
13.
ACS Chem Biol ; 19(6): 1237-1242, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38723147

RESUMO

As an important functional monosaccharide, glucosamine (GlcN) is widely used in fields such as medicine, food nutrition, and health care. Here, we report a distinct GlcN biosynthesis method that utilizes engineered Bacillus subtilis glucosamine-6-phosphate synthase (BsGlmS) to convert D-fructose to directly generate GlcN. The best variant obtained by using a combinatorial active-site saturation test/iterative saturation mutagenesis (CAST/ISM) strategy was a quadruple mutant S596D/V597G/S347H/G299Q (BsGlmS-BK19), which has a catalytic activity 1736-fold that of the wild type toward D-fructose. Upon using mutant BK19 as a whole-cell catalyst, D-fructose was converted into GlcN with 65.32% conversion in 6 h, whereas the wild type only attained a conversion rate of 0.31% under the same conditions. Molecular docking and molecular dynamics simulations were implemented to provide insights into the mechanism underlying the enhanced activity of BK19. Importantly, the BsGlmS-BK19 variant specifically catalyzes D-fructose without the need for phosphorylated substrates, representing a significant advancement in GlcN biosynthesis.


Assuntos
Bacillus subtilis , Glucosamina , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante) , Engenharia de Proteínas , Glucosamina/biossíntese , Glucosamina/metabolismo , Glucosamina/química , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/química , Bacillus subtilis/enzimologia , Bacillus subtilis/metabolismo , Bacillus subtilis/genética , Simulação de Acoplamento Molecular , Frutose/metabolismo , Frutose/química , Frutose/biossíntese , Simulação de Dinâmica Molecular , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Domínio Catalítico
14.
Aging (Albany NY) ; 16(11): 9386-9409, 2024 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-38819232

RESUMO

OBJECTIVE: To investigate whether telomerase-associated lncRNA expression affects the prognosis and anti-tumor immunity of patients with renal clear cell carcinoma (ccRCC). METHODS: A series of analyses were performed to establish a prognostic risk model and validate its accuracy. Immune-related analyses were performed to assess further the association between immune status, tumor microenvironment, and prognostic risk models. RESULTS: Eight telomerase-associated lncRNAs associated with prognosis were identified and applied to establish a prognostic risk model. Overall survival was higher in the low-risk group. CONCLUSION: The established prognostic risk model has a good predictive ability for the prognosis of ccRCC patients and provides a new possible therapeutic target for ccRCC.


Assuntos
Carcinoma de Células Renais , Imunoterapia , Neoplasias Renais , RNA Longo não Codificante , Telomerase , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/terapia , Carcinoma de Células Renais/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Humanos , Neoplasias Renais/genética , Neoplasias Renais/imunologia , Neoplasias Renais/mortalidade , Neoplasias Renais/terapia , Telomerase/genética , Telomerase/metabolismo , Prognóstico , Imunoterapia/métodos , Regulação Neoplásica da Expressão Gênica , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Transdução de Sinais/genética , Masculino , Feminino , Redes Reguladoras de Genes
15.
Food Funct ; 15(11): 5942-5954, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38738974

RESUMO

Our laboratory previously extracted bound polyphenols (BPP) in insoluble dietary fiber from navel orange peel (NOP-IDF), and the aim of this study was to investigate the anti-inflammatory activity and potential molecular mechanisms of BPP by establishing an LPS-induced intestinal-like Caco-2/RAW264.7 co-culture inflammation model. The results demonstrated that BPP reduced the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), as well as the production of pro-inflammatory cytokines, nitric oxide (NO), and reactive oxidative species (ROS) during the inflammatory damage process. Furthermore, BPP alleviated the lipopolysaccharides (LPS)-induced intestinal barrier damage by attenuating the decrease in trans-epithelial electrical resistance (TEER), diamine oxidase (DAO) activity, and intestinal alkaline phosphatase (IAP) activity, as well as the downregulation of ZO-1, Occludin, and Claudin-1 protein expression levels. RNA-seq results on RAW264.7 cells in the co-culture model showed that the NF-κB and JAK-STAT pathways belonged to the most significantly affected signaling pathways in the KEGG analysis, and western blot confirmed that they are essential for the role of BPP in intestinal inflammation. Additionally, overexpression of the granulocyte-macrophage colony-stimulating factor (CSF2) gene triggered abnormal activation of the NF-κB and JAK-STAT pathways and high-level expression of inflammatory factors, while BPP effectively improved this phenomenon. The above results suggested that BPP could inhibit intestinal inflammatory injury and protect intestinal barrier integrity through CSF2-mediated NF-κB and JAK-STAT pathways.


Assuntos
Citrus sinensis , Técnicas de Cocultura , Fibras na Dieta , Lipopolissacarídeos , Polifenóis , Transdução de Sinais , Animais , Humanos , Camundongos , Células CACO-2 , Citrus sinensis/química , Fibras na Dieta/farmacologia , Frutas/química , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Janus Quinases/metabolismo , Lipopolissacarídeos/efeitos adversos , NF-kappa B/metabolismo , NF-kappa B/genética , Polifenóis/farmacologia , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição STAT/metabolismo
16.
Sci Total Environ ; 927: 172338, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608897

RESUMO

Algal blooms in lakes have been a challenging environmental issue globally under the dual influence of human activity and climate change. Considerable progress has been made in the study of phytoplankton dynamics in lakes; The long-term in situ evolution of dominant bloom-forming cyanobacteria in meso-eutrophic plateau lakes, however, lacks systematic research. Here, the monthly parameters from 12 sampling sites during the period of 1997-2022 were utilized to investigate the underlying mechanisms driving the superiority of bloom-forming cyanobacteria in Erhai, a representative meso-eutrophic plateau lake. The findings indicate that global warming will intensify the risk of cynaobacteria blooms, prolong Microcystis blooms in autumn to winter or even into the following year, and increase the superiority of filamentous Planktothrix and Cylindrospermum in summer and autumn. High RUETN (1.52 Biomass/TN, 0.95-3.04 times higher than other species) under N limitation (TN < 0.5 mg/L, TN/TP < 22.6) in the meso-eutrophic Lake Erhai facilitates the superiority of Dolichospermum. High RUETP (43.8 Biomass/TP, 2.1-10.2 times higher than others) in TP of 0.03-0.05 mg/L promotes the superiority of Planktothrix and Cylindrospermum. We provided a novel insight into the formation of Planktothrix and Cylindrospermum superiority in meso-eutrophic plateau lake with low TP (0.005-0.07 mg/L), which is mainly influenced by warming, high RUETP and their vertical migration characteristics. Therefore, we posit that although the obvious improvement of lake water quality is not directly proportional to the control efficacy of cyanobacterial blooms, the evolutionary shift in cyanobacteria population structure from Microcystis, which thrives under high nitrogen and phosphorus conditions, to filamentous cyanobacteria adapted to low nitrogen and phosphorus levels may serve as a significant indicator of water quality amelioration. Therefore, we suggest that the risk of filamentous cyanobacteria blooms in the meso-eutrophic plateau lake should be given attention, particularly in light of improving water quality and global warming, to ensure drinking water safety.


Assuntos
Cianobactérias , Eutrofização , Lagos , Temperatura , Lagos/microbiologia , Lagos/química , China , Monitoramento Ambiental , Nitrogênio/análise , Fitoplâncton , Mudança Climática , Estações do Ano , Fósforo/análise , Nutrientes/análise , Aquecimento Global
17.
AMB Express ; 14(1): 48, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38678482

RESUMO

Escherichia coli Nissle 1917 (EcN) is an important chassis strain widely used for the development of live biotherapeutic products (LBPs). EcN strain naturally harbors two cryptic plasmids with unknown function. During the development of LBPs using EcN strain, the cryptic plasmids were cured usually to avoid plasmid incompatibility or alleviate metabolic burdens associated with these cryptic plasmids. While the cryptic plasmids curing in EcN may appear to be a routine procedure, the comprehensive impact of cryptic plasmids curing on the EcN strain remains incompletely understood. In the present study, the effects of cryptic plasmids curing on EcN were investigated using transcriptome sequencing. The results revealed that only a small number of genes showed significant changes in mRNA levels after cryptic plasmid curing (4 upregulated and 6 downregulated genes), primarily involved in amino acid metabolism. Furthermore, the flu gene showed the most significant different expression, encoding Antigen 43 (Ag43) protein, a Cah family adhesin. Mass spectrometry analysis further confirmed the significant increase in Ag43 expression. Ag43 is commonly present in Escherichia coli and mediates the bacterial autoaggregation. However, despite the upregulation of Ag43 expression, no Ag43-mediated cell self-sedimentation was observed in the cured EcN strain. These findings contribute to making informed decisions regarding the curing of the cryptic plasmids when Escherichia coli Nissle 1917 is used as the chassis strain.

18.
Food Funct ; 15(8): 4154-4169, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38482844

RESUMO

The consumption of dietary fiber is beneficial for gut health, but the role of bound polyphenols in dietary fiber has lacked systematic study. The aim of this study is to evaluate the ameliorative effect of mung bean coat dietary fiber (MDF) on DSS-induced ulcerative colitis in mice in the presence and absence of bound polyphenols. Compared to polyphenol-removed MDF (PR-MDF), MDF and formulated-MDF (F-MDF,backfilling polyphenols by the amount of extracted from MDF into PR-MDF) alleviated symptoms such as weight loss and colonic injury in mice with colitis, effectively reduced excessive inflammatory responses, and the bound polyphenols restored the integrity of the intestinal barrier by promoting the expression of tight junction proteins. Additionally, bound polyphenols restored the expression of autophagy-related proteins (mTOR, beclin-1, Atg5 and Atg7) and inhibited the excessive expression of apoptotic-related proteins (Bax, caspase-9, and caspase-3). Furthermore, bound polyphenols could ameliorate the dysregulation of the intestinal microbiota by increasing the abundance of beneficial bacteria and inhibiting the abundance of harmful bacteria. Thus, it can be concluded that the presence of bound polyphenols in MDF plays a key role in the alleviation of DSS-induced ulcerative colitis.


Assuntos
Colite Ulcerativa , Sulfato de Dextrana , Fibras na Dieta , Microbioma Gastrointestinal , Polifenóis , Vigna , Animais , Polifenóis/farmacologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colite Ulcerativa/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Fibras na Dieta/farmacologia , Sulfato de Dextrana/efeitos adversos , Vigna/química , Masculino , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Humanos
19.
Angew Chem Int Ed Engl ; 63(20): e202402621, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38443314

RESUMO

The incorporation of pentagon-heptagon pairs into helical nanographenes lacks a facile synthetic route, and the impact of these pairs on chiroptical properties remains unclear. In this study, a method for the stepwise construction of pentagon-heptagon pairs in helical nanographenes by the dehydrogenation of [6]helicene units was developed. Three helical nanographenes containing pentagon-heptagon pairs were synthesized and characterized using this approach. A wide variation in the molecular geometries and photophysical properties of these helical nanographenes was observed, with changes in the helical length of these structures and the introduction of the pentagon-heptagon pairs. The embedded pentagon-heptagon pairs reduced the oxidation potential of the synthesized helical nanographenes. The high isomerization energy barriers enabled the chiral resolution of the helicene enantiomers. Chiroptical investigations revealed remarkably enhanced circularly polarized luminescence and luminescence dissymmetry factors with an increasing number of the pentagon-heptagon pairs.

20.
Int J Biol Macromol ; 266(Pt 1): 131179, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552698

RESUMO

Collagen (COL) is the most widespread functional protein. Designing and developing dual-dynamic-bond cross-linked COL adhesive hydrogel sealants with multifunctional is highly advantageous for achieving a superior wound closure effect and hemostasis. In this study, we developed hybrid hydrogels consisting of fish-skin COL, oxidized sodium alginate (OSA), borax and polyvinyl alcohol (PVA) to enhance full-thickness wound healing. The hydrogels were furnished with first-rate self-healing capabilities through the dual-dynamic-bond cross-linking of dynamic Schiff base bonds (COL-OSA) and diol boric acid bonds (OSA-borax) with reversible breakage and re-formation. Moreover, the incorporation of PVA stimulated the formation of hydrogen bonds in the system, bolstering the stability of the hydrogel framework. The prepared hydrogel manifests self-healing, injectability, multifunctional adhesiveness and biodegradability. In vivo assessment of the hemostatic capacity of COSP20 hydrogel was superior to gauze both in the mice liver injury model and mice tail amputation model. In addition, a full-thickness skin wound model in mice revealed that the COSP20 hydrogel facilitated faster wound closure by accelerating reepithelialization, COL deposition and angiogenesis. These findings illustrate the potential of hybrid fish-skin COL-based hydrogels to enhance wound healing and promote rapid tissue repair, and provide new possibilities for the effective utilization of marine fishery resources.


Assuntos
Boratos , Colágeno , Peixes , Hemostasia , Hidrogéis , Pele , Cicatrização , Animais , Cicatrização/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Colágeno/química , Hemostasia/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/lesões , Alginatos/química , Alginatos/farmacologia , Álcool de Polivinil/química
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