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1.
Mol Biotechnol ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780825

RESUMO

Osteoporosis is a common chronic bone metabolism disorder characterized by decreased bone mass and reduced bone density in the bone tissue. Osteoporosis can lead to increased fragility of the skeleton, making it prone to brittle fractures. Osteoclasts are macrophage-like cells derived from hematopoietic stem cells, and their excessive activity in bone resorption leads to lower bone formation than absorption during bone remodeling, which is one of the important factors inducing osteoporosis. Therefore, how to inhibit osteoclast formation and reducing bone loss is an important direction for treating osteoporosis. Sophoraflavanone G, derived from Sophora flavescens Alt and Rhizoma Drynariae, is a flavonoid compound with various biological activities. However, there have been few studies on osteoporosis and osteoclasts so far. Therefore, we hypothesize that genistein G can inhibit osteoclast differentiation, alleviate bone loss phenomenon, and conduct in vitro and in vivo experiments for research and verification purposes.

2.
Proc Natl Acad Sci U S A ; 121(22): e2320468121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38768356

RESUMO

Spontaneous gain or loss of DNA methylation occurs in plant and animal genomes, and DNA methylation changes can lead to meiotically stable epialleles that generate heritable phenotypic diversity. However, it is unclear whether transgenerational epigenetic stability may be regulated by any cellular factors. Here, we examined spontaneously occurring variations in DNA methylation in wild-type and ros1 mutant Arabidopsis plants that were propagated for ten generations from single-seed descent. We found that the ros1 mutant, which is defective in active DNA demethylation, showed an increased transgenerational epimutation rate. The ros1 mutation led to more spontaneously gained methylation than lost methylation at individual cytosines, compared to the wild type which had similar numbers of spontaneously gained and lost methylation cytosines. Consistently, transgenerational differentially methylated regions were also biased toward hypermethylation in the ros1 mutant. Our results reveal a genetic contribution of the ROS1 DNA demethylase to transgenerational epigenetic stability and suggest that ROS1 may have an unexpected surveillance function in preventing transgenerational DNA methylation increases.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Desmetilação do DNA , Metilação de DNA , Epigênese Genética , Mutação , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , DNA de Plantas/genética , DNA de Plantas/metabolismo , Proteínas Nucleares
3.
J Interpers Violence ; : 8862605241253039, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769876

RESUMO

Bystanders play a role in school bullying; more specifically, the defending behaviors of bystanders play an important role in stopping bullying. This study explores the relationship between defending behaviors and family functioning in the context of school bullying from a family perspective. The role played by individual characteristics (empathy and gender) in this relationship was also focused on. The participants were 994 adolescents (average age = 13.34 ± 0.92 years) from the east of China. They completed the McMaster Family Assessment Device, the Basic Empathy Scale, and the Defending Behaviors subscale of the Participant Role Questionnaire. After controlling for residence and age, we found that family functioning significantly and positively influenced defending behaviors, and cognitive empathy rather than affective empathy mediated the relationship between family functioning and defending behaviors. In addition, family functioning influenced defending behaviors in boys more strongly than in girls. This study may increase the likelihood that bystanders will engage in defending behaviors by informing interventions for school bullying.

4.
J Org Chem ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728220

RESUMO

An efficient, practical, and metal-free protocol for the synthesis of silicon-containing isoindolin-1-ones and deuterated analogues via the synergistic combination of an organic photoredox and hydrogen atom transfer process is described. This strategy features mild reaction conditions, high atom economy, and excellent functional group compatibility, delivering a myriad of structurally diverse and valuable products with good to excellent yields.

5.
Sci Total Environ ; 931: 172920, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38701933

RESUMO

Scleractinian corals are capable of accumulating polycyclic aromatic hydrocarbons (PAHs) in reef environments; however, the mechanism behind their PAHs tolerance is unknown. This study investigated the occurrence and bioaccumulation of PAHs in coral reef ecosystems and examined the physiological responses induced by PAHs in coral hosts and their algal symbionts, the massive coral Galaxea fascicularis and branching coral Pocillopora damicornis. G. fascicularis had a higher PAHs accumulation capacity than P. damicornis. Both the coral hosts and algal symbionts preferentially accumulated acenaphthene, dibenzo(a,h)anthracene, and benzo(a)pyrene. The accumulated PAHs by G. fascicularis and P. damicornis hosts was accompanied by a reduction in detoxification ability. The accumulated PAHs could induce oxidative stress in P. damicorni hosts, thus G. fascicularis demonstrated a greater tolerance to PAHs compared to P. damicornis. Meanwhile, their algal symbionts had fewer physiological responses to accumulated PAHs than the coral hosts. Negative effects were not observed with benzo(a)pyrene. Taken together, these results suggest massive and branching scleractinian corals have different PAHs bioaccumulation and tolerance mechanisms, and indicate that long-term PAHs pollution could cause significant alterations of community structures in coral reef ecosystems.


Assuntos
Antozoários , Recifes de Corais , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Antozoários/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo , Bioacumulação , Monitoramento Ambiental , Simbiose
6.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38709871

RESUMO

Chirality, a fundamental property of matter, is often overlooked in the studies of marine organic matter cycles. Dihydroxypropanesulfonate (DHPS), a globally abundant organosulfur compound, serves as an ecologically important currency for nutrient and energy transfer from phytoplankton to bacteria in the ocean. However, the chirality of DHPS in nature and its transformation remain unclear. Here, we developed a novel approach using chiral phosphorus-reagent labeling to separate DHPS enantiomers. Our findings demonstrated that at least one enantiomer of DHPS is present in marine diatoms and coccolithophores, and that both enantiomers are widespread in marine environments. A novel chiral-selective DHPS catabolic pathway was identified in marine Roseobacteraceae strains, where HpsO and HpsP dehydrogenases at the gateway to DHPS catabolism act specifically on R-DHPS and S-DHPS, respectively. R-DHPS is also a substrate for the dehydrogenase HpsN. All three dehydrogenases generate stable hydrogen bonds between the chirality-center hydroxyls of DHPS and highly conserved residues, and HpsP also form coordinate-covalent bonds between the chirality-center hydroxyls and Zn2+, which determines the mechanistic basis of strict stereoselectivity. We further illustrated the role of enzymatic promiscuity in the evolution of DHPS metabolism in Roseobacteraceae and SAR11. This study provides the first evidence of chirality's involvement in phytoplankton-bacteria metabolic currencies, opening a new avenue for understanding the ocean organosulfur cycle.


Assuntos
Diatomáceas , Fitoplâncton , Rhodobacteraceae , Fitoplâncton/metabolismo , Estereoisomerismo , Diatomáceas/metabolismo , Rhodobacteraceae/metabolismo , Rhodobacteraceae/genética , Haptófitas/metabolismo , Oxirredutases/metabolismo , Oxirredutases/genética , Biotransformação , Redes e Vias Metabólicas , Alcanossulfonatos
7.
Aging (Albany NY) ; 162024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38809518

RESUMO

BACKGROUND: The role and clinical significance of the response gene to complement 32 (RGC32) in various cancers have been documented, yet its implications in clear cell Renal Cell Carcinoma (ccRCC) remain underexplored. METHODS: This study investigated RGC32's diagnostic and prognostic relevance in ccRCC using bioinformatics methods with data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). The impact of RGC32 on ccRCC progression was assessed through nude mouse tumor assays. Immunohistochemistry evaluated RGC32 levels in ccRCC and adjacent normal tissues, while cell proliferation, migration, and invasion capabilities were analyzed using CCK-8, monoclonal proliferation assays, Transwell, and wound healing assays, respectively. Western blotting measured relevant protein expressions. RESULTS: Bioinformatics analysis highlighted RGC32's significant role in ccRCC pathogenesis. Elevated RGC32 expression in ccRCC tissues was linked to disease progression. Functionally, RGC32 was found to enhance the expression of proteins such as p-PI3K, CyclinA1, CyclinD1, p-STAT3, MMP2, MMP3, MMP9, p-SMAD2/3, Snail, Slug, and N-Cadherin via the NF-κB/SHP2/EGFR pathway, while decreasing E-cadherin levels. Moreover, RGC32 facilitated ccRCC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). CONCLUSION: RGC32 is a pivotal factor in ccRCC development, primarily through the activation of the NF-κB/SHP2/EGFR signaling pathway.

8.
STAR Protoc ; 5(2): 102998, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38573862

RESUMO

We recently identified a class of small cytosolic double-stranded DNA (scDNA) approximately 20-40 bp in size in human and mouse cells. Here, we present a protocol for scDNA isolation from cultured murine cells. We describe steps for cytosolic compartment separation, DNA isolation in the cytosolic fraction using phenol-chloroform extraction, and ethanol precipitation. We then detail procedures for denaturing purified cytosolic DNA through urea polyacrylamide gel electrophoresis and obtaining scDNA in the cytosolic DNA fraction via gel purification. For complete details on the use and execution of this protocol, please refer to Liu et al.1.

9.
Langmuir ; 40(18): 9785-9796, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38680055

RESUMO

Surface modification, such as bioinspired nanostructured doubly reentrant surfaces that have presented superhydrophobic wettability even under low-surface-tension liquid, is a very promising technology for controlling droplet dynamics, heat transfer, and evaporation. In this article, we investigate the interfacial effects of nanostructured doubly reentrant surfaces on the flow behaviors and local concentration evolution during the evaporation of an ethanol/water multicomponent droplet. Using particle image velocimetry (PIV) and novel aggregate-induced emission-based (AIE) techniques, the flow patterns and local concentration distributions on both hydrophobic and nanostructured doubly reentrant surfaces were probed and compared. It is found that in addition to the established Marangoni flow-dominated stage, transition stage, and buoyancy-induced flow-dominated stage, a new transition stage and a rolling stage for the nanostructured doubly reentrant surface are detected in the late evaporation period. Differences in the local concentration distribution evolution occur depending on the hydrophobicity of the surface on which the droplet is placed. For the hydrophobic surface, a nonuniform local concentration distribution exists consistently, with a high water fraction in a shell-shaped region near the liquid-air interface and a secondary concentration gradient within this shell-shaped region. The concentration distribution on the nanostructured doubly reentrant surface evolves in a more complex manner, with a strip-shaped region of high water fraction forming in the intermediate stage and then reorganized by rolling flow in the late stage. Finally, theoretical analysis combining PIV and AIE visualization results reveals that the variations in droplet concentration distributions on surfaces with different hydrophobicities exert a significant impact on evaporative behaviors. These behaviors, in turn, affect the evolution of the local concentration distribution.

10.
Cancer Lett ; 590: 216870, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38614386

RESUMO

To seed lethal secondary lesions, circulating tumor cells (CTCs) must survive all rate-limiting factors during hematogenous dissemination, including fluid shear stress (FSS) that poses a grand challenge to their survival. We thus hypothesized that CTCs with the ability to survive FSS in vasculature might hold metastasis-initiating competence. This study reported that FSS of physiologic magnitude selected a small subpopulation of suspended tumor cells in vitro with the traits of metastasis-initiating cells, including stemness, migration/invasion potential, cellular plasticity, and biophysical properties. These shear-selected cells generated local and metastatic tumors at the primary and distal sites efficiently, implicating their metastasis competence. Mechanistically, FSS activated the mechanosensitive protein CXCR4 and the downstream PI3K/AKT signaling, which were essential in shear-mediated selection of metastasis-competent CTCs. In summary, these findings conclude that CTCs with metastasis-initiating competence survive FSS during hematogenous dissemination through CXCR4-PI3K/AKT signaling, which may provide new therapeutic targets for the early prevention of tumor metastasis.


Assuntos
Células Neoplásicas Circulantes , Transdução de Sinais , Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Movimento Celular , Metástase Neoplásica , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores CXCR4/metabolismo , Estresse Mecânico
11.
Antonie Van Leeuwenhoek ; 117(1): 67, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607451

RESUMO

A bacterial strain PJ23T was isolated from the rhizosphere soil of Elymus dahuricus Turcz. sampled from a temperate semi-arid steppe in the northern of Inner Mongolia Autonomous Region, China. The strain is Gram-stain-negative, aerobic, light-pink, short rod-shaped, and non-spore-forming. Cell growth could be observed at 4-29℃ (optimal at 24℃), pH 6.0-8.6 (optimal at 8.0) and in the presence of 0-5.0% (w/v) NaCl (optimal at 2.5%). The major cellular fatty acids of strain PJ23T were Summed feature 8 (C18:1 ω6c and/or C18:1 ω7c) (39.42%) and C16:0 (9.60%). The polar lipids were phosphatidylcholine, two unidentified glycolipids, one unidentified aminophospholipid, and two other unidentified polar lipids. The major respiratory quinone was ubiquinone-10. Phylogeny analysis based on 16S rRNA gene sequences retrieved from the genomes showed that, the strain was closely related to the species Terrihabitans soli IZ6T and Flaviflagellibacter deserti SYSU D60017T, with the sequence similarities of 96.79% and 96.15%, respectively. The G + C content was 65.23 mol% calculated on draft genome sequencing. Between the strains PJ23T and Terrihabitans soli IZ6T, the average nucleotide identity (ANI), amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) was 73.39%,71.12% and 15.7%, these values were lower than the proposed and generally accepted species boundaries of ANI, AAI and dDDH, respectively. Based on phenotypic, chemotaxonomic, and phylogenetic characteristics, strain PJ23T represents a novel species of Terrihabitans, for which the name Terrihabitans rhizophilus sp. nov. is proposed. The type strain is PJ23T (= KCTC 92977 T = CGMCC 1.61577 T).


Assuntos
Alphaproteobacteria , Rizosfera , Filogenia , RNA Ribossômico 16S/genética , Aminoácidos , Ácidos Graxos , DNA
12.
Antonie Van Leeuwenhoek ; 117(1): 66, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607563

RESUMO

The pink-colored and strictly aerobic bacterium strain, designated as TK19036T, was isolated from mesopelagic layer of the Southwest Indian Ocean. This novel isolate can grow at 10-45 °C (optimum, 30 °C), pH 6.0-8.0 (optimum, pH 7.0), and 2-14% NaCl concentrations (w/v) (optimum, 6%). The predominant respiratory quinone was Menaquinone-7. Major polar lipid profiles contained two aminolipids, aminophospholipid, two glycolipids, phosphatidylethanolamine, and three unknown polar lipids. The preponderant cellular fatty acids were iso-C15:0, C16:1 ω5c and iso-C17:0 3-OH. Phylogenetic analyses based on 16S rRNA gene sequence uncovered that the strain TK19036T pertained to the family Catalinimonadaceae under phylum Bacteroidota, and formed a distinct lineage with the closed species Tunicatimonas pelagia NBRC 107804T. The up-to-bacteria-core gene phylogenetic trees also demonstrated a deep and novel branch formed by the strain TK19036T within the family Catalinimonadaceae. Based on chemotaxonomic, phylogenetic and genomic features presented above, strain TK19036T represents a novel species from a novel genus of the family Catalinimonadaceae, for which the name Roseihalotalea indica gen. nov. sp. nov. is proposed. The type strain is TK19036T (= CGMCC 1.18940T = NBRC 116371T).


Assuntos
Bacteroidetes , Ácidos Graxos , Oceano Índico , Filogenia , RNA Ribossômico 16S/genética , Bacteroidetes/genética
13.
Sci Total Environ ; 926: 171599, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38490410

RESUMO

Estuarine-offshore sediments accumulate substantial particulate organic matter, containing organic sulfur as a key component. However, the distribution and sources of organic sulfur in such environments remain poorly understood. This study investigated organic sulfur in the Yangtze River Estuary and adjacent East China Sea. Dissolved organic sulfur varied from 0.65 to 1.99 µmol/L (molar S:C 0.006-0.018), while particulate organic sulfur ranged from 0.42 to 2.69 µmol/L (molar S:C 0.007-0.082). Sedimentary organic sulfur exhibited a similar molar S:C ratio (0.014-0.071) to particulate organic sulfur in bottom water, implying that particulate matter deposition is a potential source. Furthermore, sediments exposed to frequent hypoxia harbored significantly higher organic sulfur and S:C values compared to non-hypoxic areas. Laboratory incubation experiments revealed the underlying mechanism: sustained activity of sulfate-reducing bacteria in hypoxic sediments led to a substantial increase in sedimentary organic sulfur (from 15 to 53 µmol/g) within 600 days. This microbially driven sulfurization rendered over 90 % of the organic sulfur resistant to acid hydrolysis. Therefore, this study demonstrates that, alongside particle deposition, microbial sulfurization significantly contributes to organic sulfur enrichment and likely promotes organic matter preservation in estuarine-offshore sediments, particularly under hypoxic conditions. This finding advances our understanding of organic sulfur sources in these vital ecosystems.


Assuntos
Ecossistema , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Enxofre , Estuários , Material Particulado , China , Sedimentos Geológicos
14.
Water Res ; 254: 121388, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38430759

RESUMO

The periodate (PI)-based advanced oxidation process is valued for environmental remediation, but current activation methods involve high costs, secondary contamination risks, and limited applicability due to external energy inputs (e.g., UV), catalyst incorporation (e.g., Fe2+), or environmental modifications (e.g., freezing). In this work, novel bioelectric activation of PI using the electrons generated by electroactive bacteria was developed and investigated for rapid removal of carbamazepine (CBZ), achieving 100 %, 100 %, and 76 % removal efficiency for 4.22 µM of CBZ in 20 min at pH 2, 120 min at pH 6.4, and HRT of 30 min at pH 8.5, respectively, with a 1 mM PI dose and without an input voltage. It was deduced that electrons derived from bacteria could directly activate PI using Ti mesh electrodes and generate •IO3 via single electron transfer under strongly acidic conditions (e.g., pH 2). Nevertheless, under weak alkaline conditions (e.g., pH 8.5), biogenic electrons indirectly activated PI by generating OH-via 4e-reduction at the Ti mesh cathode, resulting in the formation of •O2- and 1O2. In addition to the metal cathode, a carbon-based cathode finely modulates the 2e-reduction, yielding H2O2 and activating PI to mainly form •OH. Moreover, primarily non-toxic IO3- was produced during treatment, while no detectable reactive iodine species (HOI, I2, and I3-) were observed. Furthermore, the bioelectric activation of PI demonstrated its capability to remove various micropollutants present in secondary-treated municipal wastewater, showcasing its broad-spectrum degradation ability. This study introduces a novel, cost-effective, and environmentally friendly PI activation technique with promising applicability for micropollutant elimination in water treatment.


Assuntos
Peróxido de Hidrogênio , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Águas Residuárias , Ácido Periódico , Oxirredução , Carbamazepina
15.
J Ginseng Res ; 48(2): 163-170, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38465221

RESUMO

Background: Mechanisms of synaptic plasticity in retinal ganglion cells (RGCs) are complex and the current knowledge cannot explain. Growth and regeneration of dendrites together with synaptic formation are the most important parameters for evaluating the cellular protective effects of various molecules. The effect of ginsenoside Rg1 (Rg1) on the growth of retinal ganglion cell processes has been poorly understood. Therefore, we investigated the effect of ginsenoside Rg1 on the neurite growth of RGCs. Methods: Expression of proteins and mRNA were detected by Western blot and qPCR. cAMP levels were determined by ELISA. In vivo effects of Rg1 on RGCs were evaluated by hematoxylin and eosin, and immunohistochemistry staining. Results: This study found that Rg1 promoted the growth and synaptic plasticity of RGCs neurite by activating the cAMP/PKA/CREB pathways. Meanwhile, Rg1 upregulated the expression of GAP43, Rac1 and PAX6, which are closely related to the growth of neurons. Meantime, H89, an antagonist of PKA, could block this effect of Rg1. In addition, we preliminarily explored the effect of Rg1 on enhancing the glycolysis of RGCs, which could be one of the mechanisms for its neuroprotective effects. Conclusion: Rg1 promoted neurite growth of RGCs through cAMP/PKA/CREB pathways. This study may lay a foundation for its clinical use of optic nerve diseases in the future.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38376765

RESUMO

BACKGROUND: Cytokine storm is known to impact the prognosis of coronavirus disease 2019 (COVID-19), since pro-inflammatory cytokine variants are associated with cytokine storm. It is tempting to speculate that pro-inflammatory cytokines variants may impact COVID-19 outcomes by modulating cytokine storm. Here, we verified this hypothesis via a comprehensive analysis. METHODS: PubMed, Cochrane Library, Central, CINAHL, and ClinicalTrials.gov were searched until December 15, 2023. Case-control or cohort studies that investigated the impacts of rs1800795 or rs1800629 on COVID-19 susceptibility, severity, mortality, IL-6, TNF-α, or CRP levels were included after an anonymous review by two independent reviewers and consultations of disagreement by a third independent reviewer. RESULTS: 47 studies (8305 COVID-19 individuals and 17,846 non-COVID-19 individuals) were analyzed. The rs1800629 A allele (adenine at the -308 position of the promoter was encoded by the A allele) was associated with higher levels of tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP). In contrast, the rs1800795 C allele (cytosine at the -174 position of the promoter was encoded by the C allele) was linked to higher levels of interleukin-6 (IL-6) and CRP. In addition, the A allele of rs1800629 increased the severity and mortality of COVID-19. However, the C allele of rs1800795 only increased COVID-19 susceptibility. CONCLUSIONS: rs1800629 and rs1800795 variants of pro-inflammatory cytokines have significant impacts on systemic inflammatory profile and COVID-19 clinical outcomes. rs1800629 may serve as a genetic marker for severe COVID-19.

17.
Molecules ; 29(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38338487

RESUMO

In this paper, a highly conductive alkali-activated graphitized carbon (a-GC) was prepared using tilapia fish scales as precursors through enzymolysis, activation and pyrolytic carbonization methods. The prepared a-GC was modified on the surface of a screen-printed carbon electrode to construct a flexible portable electrochemical sensing platform, which was applied to the differential pulse voltametric detection of dopamine (DA) using a U-disk electrochemical workstation combined with a smart phone and Bluetooth. The prepared a-GC possesses good electrical conductivity, a large specific surface area and abundant active sites, which are beneficial for the electrooxidation of DA molecules and result in excellent sensitivity and high selectivity for DA analysis. Under the optimal conditions, the oxidation peak current of DA increased gradually, with its concentrations in the range from 1.0 µmol/L to 1000.0 µmol/L, with the detection limit as low as 0.25 µmol/L (3S/N). The proposed sensor was further applied to the determination of DA in human sweat samples, with satisfactory results, which provided an opportunity for developing noninvasive early diagnosis and nursing equipment.


Assuntos
Carbono , Dopamina , Animais , Humanos , Dopamina/química , Carbono/química , Técnicas Eletroquímicas/métodos , Reprodutibilidade dos Testes , Carvão Vegetal , Eletrodos
18.
Acta Biomater ; 176: 321-333, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38272199

RESUMO

Hepatocellular carcinoma (HCC) cells, especially those with metastatic competence, show reduced stiffness compared to the non-malignant counterparts. However, it is still unclear whether and how the mechanics of HCC cells influence their migration and invasion. This study reports that HCC cells with enhanced motility show reduced mechanical stiffness and cytoskeleton, suggesting the inverse correlation between cellular stiffness and motility. Through pharmacologic and genetic approaches, inhibiting actomyosin activity reduces HCC cellular stiffness but promotes their migration and invasion, while activating it increases cell stiffness but impairs cell motility. Actomyosin regulates cell motility through the influence on cellular stiffness. Mechanistically, weakening/strengthening cells inhibits/promotes c-Jun N terminal kinase (JNK) phosphorylation, activation/inhibition of which rescues the effects of cell mechanics on their migration and invasion. Further, HCC cancer stem cells (CSCs) exhibit higher motility but lower stiffness than control cells. Increasing CSC stiffness weakens migration and invasion through the activation of JNK signaling. In conclusion, our findings unveil a new regulatory role of actomyosin-mediated cellular mechanics in tumor cell motility and present new evidence to support that tumor cell softening may be one driving force for HCC metastasis. STATEMENT OF SIGNIFICANCE: Tumor cells progressively become softened during metastasis and low cell stiffness is associated with high metastatic potential. However, it remains unclear whether tumor cell softening is a by-product of or a driving force for tumor progression. This work reports that the stiffness of hepatocellular carcinoma cells is linked to their migration and invasion. Importantly, tumor cell softening promotes migration and invasion, while cell stiffening impairs the mobility. Weakening/strengthening cells inhibits/promotes JNK phosphorylation, activation/inhibition of which rescues the effects of cell mechanics on their migration and invasion ability. Further, stiffening liver cancer stem cells attenuates their motility through activating JNK signaling. In summary, our study uncovers a previously unappreciated role of tumor cell mechanics in migration and invasion and implicates the therapeutic potential of cell mechanics in the mechanotargeting of metastasis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Actomiosina , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Invasividade Neoplásica
19.
Comput Struct Biotechnol J ; 23: 406-416, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38235362

RESUMO

Members of the phylum Bacteroidetes play a key role in the marine carbon cycle through their degradation of polysaccharides via carbohydrate-active enzymes (CAZymes) and polysaccharide utilization loci (PULs). The discovery of novel CAZymes and PULs is important for our understanding of the marine carbon cycle. In this study, we isolated and identified a potential new genus of the family Catalimonadaceae, in the phylum Bacteroidetes, from the southwest Indian Ocean. Strain TK19036, the type strain of the new genus, is predicted to encode CAZymes that are relatively abundant in marine Bacteroidetes genomes. Tunicatimonas pelagia NBRC 107804T, Porifericola rhodea NBRC 107748T and Catalinimonas niigatensis NBRC 109829T, which exhibit 16 S rRNA similarities exceeding 90% with strain TK19036, and belong to the same family, were selected as reference strains. These organisms possess a highly diverse repertoire of CAZymes and PULs, which may enable them to degrade a wide range of polysaccharides, especially pectin and alginate. In addition, some secretory CAZymes in strain TK19036 and its relatives were predicted to be transported by type IX secretion system (T9SS). Further, to the best of our knowledge, we propose the first reported "hybrid" PUL targeting alginates in T. pelagia NBRC 107804T. Our findings provide new insights into the polysaccharide degradation capacity of marine Bacteroidetes, and suggest that T9SS may play a more important role in this process than previously believed.

20.
ACS Omega ; 9(1): 817-827, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222570

RESUMO

Inflammation, extracellular matrix metabolic dysfunction, and oxidative stress are key pathogenic characteristics of intervertebral disk degeneration (IVDD), a major pathogenic cause of low back pain. Esculetin possesses anti-injury, anti-inflammation, and antinociceptive properties. This study aimed to explore its role in IVDD. In this research, esculetin exhibited little cytotoxicity to human nucleus pulposus cells (NPCs). Moreover, esculetin increased cell viability under IL-1ß stimulation but attenuated IL-1ß-induced cell apoptosis and caspase-3 activity. Furthermore, IL-1ß-evoked increases in intracellular reactive oxygen species and malondialdehyde (MDA) levels, and decreases in superoxide dismutase (SOD) activity were reversed after esculetin treatment, indicating the antioxidative stress efficacy of esculetin. Esculetin alleviated the inhibitory effects of IL-1ß on the transcription and protein expression of anabolic biomarkers (collagen II and aggrecan), accompanied by decreases in expression and release of catabolic biomarkers MMP-3 and MMP-13 from NPCs. Moreover, IL-1ß exposure enhanced the expression levels of the inflammatory mediator nitric oxide and inflammatory cytokine IL-6 and TNF-α, which were overturned after esculetin treatment. Additionally, esculetin activated the nuclear factor-erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) to inhibit the activation of nuclear factor κB (NF-κB) signaling in NPCs. Importantly, suppression of Nrf2 signaling reversed the protective efficacy of esculetin against IL-1ß-mediated oxidative injury, matrix metabolism disruption, and inflammatory response in NPCs. Together, esculetin may alleviate IL-1ß-induced dysfunction in NPCs by regulating the Nrf2/HO-1/NF-kb signaling, indicating its potential as a promising therapeutic agent against IVDD.

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