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1.
Nutrients ; 16(13)2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38999898

ABSTRACT

Alpinia officinarum Hance is rich in carbohydrates and is flavored by natives. The polysaccharide fraction 30 is purified from the rhizome of A. officinarum Hance (AOP30) and shows excellent immunoregulatory ability when administered to regulate immunity. However, the effect of AOP30 on the intestinal epithelial barrier is not well understood. Therefore, the aim of this study is to investigate the protective effect of AOP30 on the intestinal epithelial barrier using a lipopolysaccharide (LPS)-induced intestinal epithelial barrier dysfunction model and further explore its underlying mechanisms. Cytotoxicity, transepithelial electrical resistance (TEER) values, and Fluorescein isothiocyanate (FITC)-dextran flux are measured. Simultaneously, the protein and mRNA levels of tight junction (TJ) proteins, including zonula occludens-1 (ZO-1), Occludin, and Claudin-1, are determined using Western blotting and reverse-transcription quantitative polymerase chain reaction methods, respectively. The results indicate that AOP30 restores the LPS-induced decrease in the TEER value and cell viability. Furthermore, it increases the mRNA and protein expression of ZO-1, Occludin, and Claudin-1. Notably, ZO-1 is the primary tight junction protein altered in response to LPS-induced intestinal epithelial dysfunction. Additionally, AOP30 downregulates the production of TNFα via the Toll-like receptor 4 (TLR4)/NF-κB signaling pathway. Collectively, the findings of this study indicate that AOP30 can be developed as a functional food ingredient or natural therapeutic agent for addressing intestinal epithelial barrier dysfunction. It sheds light on the role of AOP30 in improving intestinal epithelial function.


Subject(s)
Alpinia , Intestinal Mucosa , Lipopolysaccharides , NF-kappa B , Polysaccharides , Rhizome , Signal Transduction , Toll-Like Receptor 4 , Toll-Like Receptor 4/metabolism , Humans , NF-kappa B/metabolism , Signal Transduction/drug effects , Rhizome/chemistry , Polysaccharides/pharmacology , Caco-2 Cells , Alpinia/chemistry , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Inflammation/drug therapy , Inflammation/metabolism , Tight Junctions/drug effects , Tight Junctions/metabolism
2.
Carbohydr Res ; 542: 109174, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38865798

ABSTRACT

A series of derivatives of salidroside with mirror isomer glucose and different phenyl moieties were synthesized by Schmidt glycosylation in satisfactory yields, and their antioxidant and anti-inflammatory activities were evaluated by using LPS-induced RAW264.7 cells. One of the synthesized derivatives ʟ-Sal-4, bearing ʟ-glycosyl and -OMe modification at the phenyl ring, exhibited high activity in inhibiting the production of pro-inflammatory cytokines and oxidative stress biomarker MDA as well as in enhancing the activity of SOD enzyme, compared with the natural product and its corresponding ᴅ-enantiomer. Further proteomic analysis suggested that ʟ-Sal-4 exerted its anti-inflammatory activity through metabolic reprogramming. The in vitro activity showed that ʟ-Sal-4 is a potent antioxidant and anti-inflammatory agent. Our finding indicated that the ʟ-glucose-derived salidroside might be a promising lead compound in the development of salidroside derivatives as therapeutic agents.


Subject(s)
Anti-Inflammatory Agents , Antioxidants , Glucosides , Phenols , Phenols/pharmacology , Phenols/chemistry , Phenols/chemical synthesis , Mice , Animals , Glucosides/pharmacology , Glucosides/chemical synthesis , Glucosides/chemistry , Antioxidants/pharmacology , Antioxidants/chemical synthesis , Antioxidants/chemistry , RAW 264.7 Cells , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemical synthesis , Anti-Inflammatory Agents/chemistry , Lipopolysaccharides/pharmacology , Lipopolysaccharides/antagonists & inhibitors , Structure-Activity Relationship , Oxidative Stress/drug effects
3.
Org Lett ; 26(12): 2478-2482, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38501865

ABSTRACT

A novel method for the glycosylation of selenoglycosides activated by iodosylbenzene was developed. The glycosylation reaction conditions were mild, fast, and efficient, with a high tolerance to diverse protecting groups and a wide substrate scope, which is advantageous for synthesizing complex glycosides. In addition, selenoglycosides were shown to be orthogonal to thioglycosides under the promotion of iodosylbenzene. Notably, a high yield of the poorly reactive glucuronidation reaction product was obtained by acetyl-protected selenoglycoside. Finally, the orthogonal one-pot synthesis of ß-(1→6) oligoglucans demonstrated the usefulness of this method in oligosaccharide synthesis.


Subject(s)
Iodobenzenes , Thioglycosides , Glycosylation , Glycosides , Oligosaccharides
4.
Cereb Cortex ; 34(3)2024 03 01.
Article in English | MEDLINE | ID: mdl-38518225

ABSTRACT

Focal seizures are a type of epileptic event that has plagued the medical community for a long time, and the existing drug treatment is mainly based on the modulation of ${GABA}_a$-receptors to affect GABAergic signaling to achieve the therapeutic purpose. The majority of research currently focuses on the impact of ${GABA}_a$-receptors on neuronal firing, failing to analyze the molecular and ionic mechanisms involved. Specifically, the research on deeper-level mechanisms on how ${GABA}_a$-receptors affect neuronal firing by altering ion activity has not been addressed. This research aimed to study the effects of different ${GABA}_a$-receptor structures on ion activity in focal seizures model by adjusting parameters of the ${GABA}_a$-receptors: the rise time constant (${tau}_1$) and decay time constant (${tau}_2$). The research indicates that as the values of ${tau}_1$ and ${tau}_2$ of the ${GABA}_a$-receptor change, the ion concentration will vary based on the change of the ${GABA}_a$-receptor potential. To a certain extent, the duration of epileptic activity will also be affected to a certain extent. In conclusion, the alteration of ${GABA}_a$-receptor structure will affect the inhibitory effect of interneurons on pyramidal neurons, and different parameters of the ${GABA}_a$-receptor will directly impact the therapeutic effect.


Subject(s)
Epilepsy , Patient Discharge , Humans , Neurons/physiology , Seizures , Receptors, GABA-A/physiology , gamma-Aminobutyric Acid/pharmacology
5.
J Environ Manage ; 355: 120491, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38437741

ABSTRACT

In the global wave of digitization, digital economic agglomeration, as an emerging model, profoundly impacts the economy, environment, and society. Countries worldwide are formulating strategies and policies to promote the development of digital economic agglomeration, yet they also face challenges of widening digital divide and environmental sustainability. Existing research primarily focuses on the positive effects of the digital economy, with limited assessment of the dual effects of digital economic agglomeration on sustainable development. This study utilizes panel data from 282 Chinese cities between 2011 and 2021, employing a two-tier stochastic frontier model. It reexamines the dual impacts and intrinsic mechanisms of digital economic agglomeration, attempting to capture regional and temporal variations in the dual effects to address this research gap. The study shows that: (1) The positive effect of digital economy agglomeration is much more than the negative effect, resulting in a positive net effect that shows an overall increasing trend with significant regional disparities. (2) Digital economic agglomeration has a significant negative spatial spillover effect, promoting local inclusive green growth while inhibiting inclusive green growth in neighboring cities. (3) Regarding the mediating mechanisms, industrial structure, technological innovation and resource allocation efficiency have positive indirect effects on inclusive green growth, while environmental regulation intensity has a negative indirect effect, and it has a nonlinear effect under the threshold constraint of the mediating mechanisms. This study provides policy insights for promoting inclusive green growth, emphasizing the need to consider regional differences in resource distribution, ecological environment, and social demands. It advocates for the organic integration of the digital economy across different regions, reducing polarization effects, and enhancing diffusion effects.


Subject(s)
Environment , Industry , Cities , Diffusion , Policy , China , Economic Development
6.
Aquat Toxicol ; 268: 106860, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38354462

ABSTRACT

Cyanobacteria cell lysates release numerous toxic substances (e.g., cyanotoxins) into the water, posing a serious threat to human health and aquatic ecosystems. Microcystins (MCs) are among the most abundant cyanotoxins in the cell lysates, with microcystin-LR (MC-LR) being one of the most common and highly toxic congeners. In this study, zebrafish (Danio rerio) were exposed to different levels MC-LR that from extracts of Microcystis aeruginosa. Changes in the MC-LR accumulations, organ coefficients, and antioxidant enzyme activities in the zebrafish were analyzed. Transgenerational reproductive toxicity of MC-LR in the maternal and paternal generations was further investigated, as well as the influences of extracts containing MC-LR exposures of the F1 on the growth of zebrafish. The study found that high levels of MC-LR could be detected in the major organs of adult zebrafish, particularly in spleen. Notably, concentration of MC-LR in the spermary was significantly higher than that in the ovarium. MC-LR could induce oxidative damage by affecting the activities of catalase and superoxide dismutase. Inherited from F0, MC-LR led to impaired development in the F1 generation. Difference in offspring survival rates could be observed in the groups with different MC-LR levels of maternal and paternal exposures. This study reveals transgenerational effects of MC-LR on the reproductive toxicity and offspring growth inhibition to the aquatic organisms, which should be emphasized in the future ecological risk assessment.


Subject(s)
Marine Toxins , Water Pollutants, Chemical , Zebrafish , Male , Animals , Female , Humans , Zebrafish/physiology , Microcystins/toxicity , Ecosystem , Water Pollutants, Chemical/toxicity , Antioxidants , Cyanobacteria Toxins
7.
Cereb Cortex ; 34(2)2024 01 31.
Article in English | MEDLINE | ID: mdl-38383723

ABSTRACT

Mild cognitive impairment (MCI) is the initial phase of Alzheimer's disease (AD). The cognitive decline is linked to abnormal connectivity between different regions of the brain. Most brain network studies fail to consider the changes in brain patterns and do not reflect the dynamic pathological characteristics of patients. Therefore, this paper proposes a method for constructing brain networks based on microstate sequences. It also analyzes the microstate temporal parameters and introduces a new feature, the brain homeostasis coefficient (Bhc), to quantify the stability of patient brain connections. The results showed that microstate class B parameters were higher in the MCI than in the HC group. Additionally, the Bhc values in most channels of the MCI and AD groups were lower than those of the HC group, with the most significant differences observed in the right frontal lobe. These differences were statistically significant (P < 0.05). The findings indicate that connectivity in the right frontal lobe may be most severely disrupted in patients with cognitive impairment. Furthermore, the Montreal Cognitive Assessment score showed a strong positive correlation with Bhc. This suggests that Bhc could be a novel biomarker for evaluating cognitive function in patients with cognitive impairment.


Subject(s)
Alzheimer Disease , Cognition Disorders , Cognitive Dysfunction , Humans , Brain/diagnostic imaging , Cognitive Dysfunction/diagnostic imaging , Cognition
8.
Anal Chem ; 96(5): 2041-2051, 2024 02 06.
Article in English | MEDLINE | ID: mdl-38270108

ABSTRACT

Ferroptosis is critical in the treatment of tumor therapies. Thus, monitoring reactive oxygen species (ROS) is of great significance for accurate assessment in ferroptosis without any interference. However, current probes for monitoring ROS during ferroptosis suffer from a drawback in that the probes consume ROS during detection, which inhibits the ferroptosis process and thus affects the accuracy and effectiveness of monitoring the process of ferroptosis. Herein, a new fluorescent donor probe, TFMU-SO2D, with the combination of the moiety of the SO2 donor is designed and synthesized by introducing the aryl boronate moieties that could give it the ability to effectively recognize ONOO-. The released SO2 could consume excess glutathione and regulate oxidative stress by elevating ROS levels, which would offset the ROS depletion by TFMU-SO2D and ensure accuracy in monitoring the ferroptosis process. The experimental results demonstrated that TFMU-SO2D possessed satisfactory performance for monitoring ONOO- as well as simultaneously releasing SO2 in oxidative stress stimulated by monensin and ferroptosis stimulated by erastin and RSL3. Additionally, the capability of SO2 synergized with ferroptosis to inhibit the viability of cancer cells was demonstrated by the CCK8 assay, which may be due to the fact that SO2 can potentiate ferroptosis cell death by increasing the ROS level. Overall, these combined results indicated that TFMU-SO2D possesses the excellent ability to precisely monitor ONOO- during ferroptosis without interference, which is significant for accurately accessing ferroptosis, cancer treatment, and drug development.


Subject(s)
Ferroptosis , Sulfur Dioxide , Reactive Oxygen Species/metabolism , Cell Death , Oxidative Stress
9.
Foods ; 13(2)2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38275700

ABSTRACT

Alpinia officinarum Hance, a well known agricultural product in the Lei Zhou peninsula, is generally rich in polysaccharides. In order to enhance the use of A. officinarum Hance polysaccharides (AOP) in functional food, AOP was extracted using an ultrasonic-assisted extraction method, and the ultrasonic extraction parameters of AOP was optimized. Furthermore, this study investigated the physicochemical and antioxidant activities of AOPs. In addition, the structural properties were preliminarily determined using Fourier-transform infrared spectroscopy (FTIR), high performance size exclusion chromatography, and a Zetasizer. Ultimately, this study explored the mechanism underlying the antioxidant activities of AOP. The results showed that the optimal ultrasonic-assisted extraction parameters were as follows: ultrasonic time, 6 min; ratio of water to material, 12 mL/g; and ultrasonic power, 380 W. Under these conditions, the maximum yield of AOPs was 5.72%, indicating that ultrasonic-assisted extraction technology is suitable for extracting AOPs due to the reduced time and water usage. Additionally, AOPs were purified using graded alcohol precipitation, resulting in three fractions (AOP30, AOP50, and AOP70). AOP30 had the lowest molecular weight of 11.07 kDa and mainly consisted of glucose (89.88%). The half inhibitory concentration (IC50) value of AOP30 and AOP70 was lower than that of AOP50 in the ability to scavenge the ABTS radical, while a reverse trend was observed in reducing ferric ions. Notably, the antioxidant activities of AOPs were highly correlated with their polydispersity index (Mw/Mn) and Zeta potential. AOP30, a negatively charged acidic polysaccharide fraction, exhibited electron donating capacities. Additionally, it displayed strong antioxidant abilities through scavenging 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radicals and reducing ferric ions. In conclusion, the present study suggests that AOP30 could be developed as an antioxidant ingredient for the food industry.

10.
BMC Genomics ; 25(1): 23, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38166718

ABSTRACT

BACKGROUND: Jianli pig, a renowned indigenous breed in China, has the characteristics of a two-end black (TEB) coat color, excellent meat quality, strong adaptability and increased prolificacy. However, there is limited information available regarding the genetic diversity, population structure and genomic regions under selection of Jianli pig. On the other hand, the genetic mechanism of TEB coat color has remained largely unknown. RESULTS: In this study, the whole genome resequencing of 30 Jianli pigs within a context of 153 individuals representing 13 diverse breeds was performed. The population structure analysis revealed that Jianli pigs have close genetic relationships with the Tongcheng pig breed, their geographical neighbors. Three methods (observed heterozygosity, expected heterozygosity, and runs of homozygosity) implied a relatively high level of genetic diversity and, a low inbreeding coefficient in Jianli compared with other pigs. We used Fst and XP-EHH to detect the selection signatures in Jianli pigs compared with Asian wild boar. A total of 451 candidate genes influencing meat quality (CREBBP, ADCY9, EEPD1 and HDAC9), reproduction (ESR1 and FANCA), and coat color (EDNRB, MITF and MC1R), were detected by gene annotation analysis. Finally, to fine-map the genomic region for the two-end black (TEB) coat color phenotype in Jianli pigs, we performed three signature selection methods between the TEB coat color and no-TEB coat color pig breeds. The current study, further confirmed that the EDNRB gene is a candidate gene for TEB color phenotype found in Chinese pigs, including Jinhua pigs, and the haplotype harboring 25 SNPs in the EDNRB gene may promote the formation of TEB coat color. Further ATAC-seq and luciferase reporter assays of these regions suggest that the 25-SNPs region was a strong candidate causative mutation that regulates the TEB coat color phenotype by altering enhancer function. CONCLUSION: Our results advanced the understanding of the genetic mechanism behind artificial selection, and provided further resources for the protection and breeding improvement of Jianli pigs.


Subject(s)
Genome , Receptor, Endothelin B , Selection, Genetic , Animals , Haplotypes , Homozygote , Phenotype , Polymorphism, Single Nucleotide , Receptor, Endothelin B/genetics , Swine/genetics
11.
Angew Chem Int Ed Engl ; 63(2): e202313985, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38014418

ABSTRACT

3-Deoxy-d-manno-oct-2-ulosonic acid (Kdo) is an eight-carbon monosaccharide found widely in bacterial lipopolysaccharides (LPSs) and capsule polysaccharides (CPSs). We developed an indirect method for the stereoselective synthesis of α-Kdo glycosides with a C3-p-tolylthio-substituted Kdo phosphite donor. The presence of the p-tolylthio group enhanced the reactivity, suppressed the formation of elimination by-products (2,3-enes), and provided complete α-stereocontrol. A variety of Kdo α-glycosides were synthesized by our method in excellent yields (up to 98 %). After glycosylation, the p-tolylthio group can be efficiently removed by free-radical reduction. Subsequently, the orthogonality of the phosphite donor and thioglycoside donor was demonstrated by the one-pot synthesis of a trisaccharide in Helicobacter pylori and Neisseria meningitidis LPS. Moreover, an efficient total synthesis route to the challenging 4,5-branched Kdo trisaccharide in LPSs from several A. baumannii strains was highlighted. To demonstrate the high reactivity of our approach further, the highly crowded 4,5,7,8-branched Kdo pentasaccharide was synthesized as a model molecule for the first time. Additionally, the reaction mechanism was investigated by DFT calculations.


Subject(s)
Glycosides , Phosphites , Oligosaccharides , Sugar Acids , Lipopolysaccharides , Trisaccharides
12.
Front Cardiovasc Med ; 10: 1161834, 2023.
Article in English | MEDLINE | ID: mdl-38075962

ABSTRACT

Objective: To compare the ultrasound guidance and traditional methods in femoral artery puncture. Methods: We searched the databases to evaluate the rate of success on first attempt and the incidence of hematoma. The random effects model was used for performing a meta-analysis to estimate the odds ratio (ORs), mean difference (MD), and 95% confidence interval (CI). Results: A total of nine articles including 2,361 patients were included in this meta-analysis. The rate of success on first attempt were 79.6% (1,289/1,619) and 54.1% (883/1,644) in patients of the ultrasound group and traditional method group, respectively [OR = 3.14 (95% CI = 2.30-4.28), combined OR value Z = 7.23 (P < 0.00001)]. The rates of incidence of hematoma in the ultrasound group and traditional puncture group patients were 1.4% (16/1,168) and 3.8% (45/1,193), respectively (OR = 0.41, 95% CI = 0.17-1.00, p = 0.05). Conclusion: Ultrasound-guided femoral artery puncture has certain advantages compared with traditional puncture with regard to success on first attempt and the incidence of hematoma. Moreover, ultrasound-guided puncture reduces the incidence of hematoma in the retrograde puncture group patients.

13.
Toxics ; 11(11)2023 Nov 11.
Article in English | MEDLINE | ID: mdl-37999575

ABSTRACT

Bisphenol AF (BPAF) is a newly identified contaminant in the environment that has been linked to impairment of the male reproductive system. However, only a few studies have systematically studied the mechanisms underlying BPAF-induced toxicity in testicular Sertoli cells. Hence, this study primarily aims to explore the toxic mechanism of BPAF on the porcine Sertoli cell line (ST cells). The effects of various concentrations of BPAF on ST cell viability and cytotoxicity were evaluated using the Counting Kit-8 (CCK-8) assay. The results demonstrated that exposure to a high concentration of BPAF (above 50 µM) significantly inhibited ST cell viability due to marked cytotoxicity. Flow cytometry analysis further confirmed that BPAF facilitated apoptosis and induced cell cycle arrest in the G2/M phase. Moreover, BPAF exposure upregulated the expression of pro-apoptotic markers BAD and BAX while downregulating anti-apoptotic and cell proliferation markers BCL-2, PCNA, CDK2, and CDK4. BPAF exposure also resulted in elevated intracellular levels of reactive oxygen species (ROS) and malondialdehyde (MDA), alongside reduced activities of the antioxidants glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). Furthermore, the ROS scavenger N-acetyl-L-cysteine (NAC) effectively blocked BPAF-triggered apoptosis and cell cycle arrest. Therefore, this study suggests that BPAF induces apoptosis and cell cycle arrest in ST cells by activating ROS-mediated pathways. These findings enhance our understanding of BPAF's role in male reproductive toxicity and provide a foundation for future toxicological assessments.

14.
Microorganisms ; 11(11)2023 Oct 26.
Article in English | MEDLINE | ID: mdl-38004647

ABSTRACT

Over the past few decades, nearly 300 known cyanotoxins and more than 2000 cyanobacterial secondary metabolites have been reported from the environment. Traditional studies have focused on the toxic cyanotoxins produced by harmful cyanobacteria, which pose a risk to both human beings and wildlife, causing acute and chronic poisoning, resulting in diarrhea, nerve paralysis, and proliferation of cancer cells. Actually, the biotechnological potential of cyanotoxins is underestimated, as increasing studies have demonstrated their roles as valuable products, including allelopathic agents, insecticides and biomedicines. To promote a comprehensive understanding of cyanotoxins, a critical review is in demand. This review aims to discuss the classifications; biosynthetic pathways, especially heterogenous production; and potential applications of cyanotoxins. In detail, we first discuss the representative cyanotoxins and their toxic effects, followed by an exploration of three representative biosynthetic pathways (non-ribosomal peptide synthetases, polyketide synthetases, and their combinations). In particular, advances toward the heterologous biosynthesis of cyanotoxins in vitro and in vivo are summarized and compared. Finally, we indicate the potential applications and solutions to bottlenecks for cyanotoxins. We believe that this review will promote a comprehensive understanding, synthetic biology studies, and potential applications of cyanotoxins in the future.

15.
Islets ; 15(1): 2252855, 2023 12 31.
Article in English | MEDLINE | ID: mdl-37660302

ABSTRACT

Somatostatin is a paracrine modulator of insulin secretion and beta cell function with pleotropic effects on glucose homeostasis. The mechanism of somatostatin-mediated communication between delta and beta cells is not well-understood, which we address in this study via the ciliary somatostatin receptor 3 (SSTR3). Primary cilia are membrane organelles that act as signaling hubs in islets by virtue of their subcellular location and enrichment in signaling proteins such as G-protein coupled receptors (GPCRs). We show that SSTR3, a ciliary GPCR, mediates somatostatin suppression of insulin secretion in mouse islets. Quantitative analysis of calcium flux using a mouse model of genetically encoded beta cell-specific GCaMP6f calcium reporter shows that somatostatin signaling alters beta cell calcium flux after physiologic glucose stimulation, an effect that depends on endogenous SSTR3 expression and the presence of intact primary cilia on beta cells. Comparative in vitro studies using SSTR isoform antagonists demonstrate a role for SSTR3 in mediating somatostatin regulation of insulin secretion in mouse islets. Our findings support a model in which ciliary SSTR3 mediates a distinct pathway of delta-to-beta cell regulatory crosstalk and may serve as a target for paracrine modulation.


Subject(s)
Cilia , Receptors, Somatostatin , Glucose , Somatostatin , Animals , Mice
16.
Water Sci Technol ; 88(1): 136-150, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37452539

ABSTRACT

Cyanotoxins produced by cyanobacteria are a significant threat to human health. However, their responses to nitrogen (N) supplies could differ between N-fixing and non-N-fixing species, which has been poorly understood. This study aimed to compare the responses of the non-N-fixing Microcystis aeruginosa and N-fixing Nostoc sp. to varying concentrations of nitrate and ammonium. This comparison had been conducted by analyzing chlorophyll-a contents, maximum quantum efficiencies of photosystem II, microcystin production, and related gene expressions. Our findings revealed that nitrate substantially stimulated the growth of both M. aeruginosa and Nostoc sp. with biomass increase by 366.2 ± 56.5 and 93.0 ± 14.0%, respectively, at 16 mg-N/L. In contrast, high ammonium concentrations suppressed their growth. Furthermore, the intracellular concentration of microcystins produced by M. aeruginosa was higher under high nitrate. Extracellular microcystins showed an opposite trend to increases in nitrate and ammonium. Ammonium increases the production and releases microcystin from Nostoc sp. N metabolism genes showed a similar trend with toxin formation genes, which were up-regulated under the high N treatments. This study provides valuable insights into the impacts of N supplies on growths of N- and non-N-fixing cyanobacteria, as well as microcystin production, which helps to develop effective strategies for managing cyanobacterial blooms.


Subject(s)
Ammonium Compounds , Microcystis , Nostoc , Humans , Microcystins , Nitrogen/metabolism , Nitrates/metabolism , Ammonium Compounds/metabolism , Nostoc/genetics , Nostoc/metabolism
17.
Entropy (Basel) ; 25(4)2023 Apr 16.
Article in English | MEDLINE | ID: mdl-37190457

ABSTRACT

As is well-known, ship-radiated noise (SN) signals, which contain a large number of ship operating characteristics and condition information, are widely used in ship recognition and classification. However, it is still a great challenge to extract weak operating characteristics from SN signals because of heavy noise and non-stationarity. Therefore, a new mono-component extraction method is proposed in this paper for taxonomic purposes. First, the non-local means algorithm (NLmeans) is proposed to denoise SN signals without destroying its time-frequency structure. Second, adaptive chirp mode decomposition (ACMD) is modified and applied on denoised signals to adaptively extract mono-component modes. Finally, sub-signals are selected based on spectral kurtosis (SK) and then analyzed for ship recognition and classification. A simulation experiment and two application cases are used to verify the effectiveness of the proposed method and the results show its outstanding performance.

18.
Behav Sci (Basel) ; 13(4)2023 Apr 03.
Article in English | MEDLINE | ID: mdl-37102816

ABSTRACT

Although there are many studies discussing the effect of Internet use on political participation, the literature has rarely focused on the relationship between the use of online-network groups and the political-participation intention in contemporary China. The discussion of this relationship is significant, as it offers a new perspective on reviewing the mobilization theory of media, especially in the context of online-network groups, and potentially provides a new channel for mobilizing a wider range of people for politics once the relationship is significant. This study aims to answer the following question: Can we predict the political-participation intention of Chinese citizens through the use of online-network groups? Based on the data of the China Social Survey 2019, this study uses the hierarchical logistic-regression method. The research finds that the specific online-network groups that can predict political-participation intention are mainly concentrated in the category of emotional relationships. Among them, although most of the online-network groups are positively correlated with political-participation intention, the possibility of generating political-participation intention of those who join the relative network group is significantly lower than for those who do not. The virtual connection built by online communication technology, the social relations, and the influence of social groups on individuals can help to explain the correlation between them.

19.
Environ Res ; 223: 115428, 2023 04 15.
Article in English | MEDLINE | ID: mdl-36746205

ABSTRACT

The over proliferation of harmful cyanobacteria and their cyanotoxins resulted in damaged aquatic ecosystem, polluted drinking water and threatened human health. Cyanophages are a kind of viruses that exclusively infect cyanobacteria, which is considered as a potential strategy to deal with cyanobacterial blooms. Nevertheless, the infecting host range and/or lysis efficiency of natural cyanophages is limited, rising the necessity of constructing non-natural cyanophages via artificial modification, design and synthesis to expand their host range and/or efficiency. The paper firstly reviewed representative cyanophages such as P60 with a short latent period of 1.5 h and S-CBS1 having a burst size up to 200 PFU/cell. To explore the in-silico design principles, we critically summarized the interactions between cyanophages and the hosts, indicating modifying the recognized receptors, enhancing the adsorption ability, changing the lysogeny and excluding the defense of hosts are important for artificial cyanophages. The research progress of synthesizing artificial cyanophages were summarized subsequently, raising the importance of developing genetic manipulation technologies and their rescue strategies in the future. Meanwhile, Large-scale preparation of cyanophages for bloom control is a big challenge. The application prospects of artificial cyanophages besides cyanobacteria bloom control like adaptive evolution and phage therapy were discussed at last. The review will promote the design, synthesis and application of cyanophages for cyanobacteria blooms, which may provide new insights for the related water pollution control and ensuring hydrosphere security.


Subject(s)
Bacteriophages , Cyanobacteria , Humans , Bacteriophages/genetics , Ecosystem
20.
Chem Commun (Camb) ; 59(10): 1337-1340, 2023 Jan 31.
Article in English | MEDLINE | ID: mdl-36645119

ABSTRACT

Mn metal batteries are rarely reported due to the lack of a stable electrolyte. Here, an N,N-dimethylformamide (DMF)-based organic electrolyte with stable Mn plating/stripping for over 500 h and high Coulombic efficiency (CE) for a Mn metal battery is presented. The battery-specifically composed of an electrolyte made of DMF and ethylenediamine (EDA), a cathode made of 3,4,9,10-perylenetetracarboxylicdiimide (PTCDI), and an anode made of Mn metal-displayed a specific capacity of 105 mA h g-1. These results indicated the effectiveness of our new method for preparing low-cost and highly stable secondary Mn ion batteries.

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