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1.
JHEP Rep ; 6(4): 100997, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38425450

RESUMO

Background & Aims: Particulate hepatitis B core antigen (HBcoreAg) is a potent immunogen used as a vaccine carrier platform. HBcoreAg produced in E. coli encapsidates random bacterial RNA (bRNA). Using the heterologous protein-prime, viral-vector-boost therapeutic hepatitis B vaccine TherVacB, we compared the properties of different HBcoreAg forms. We explored how the content of HBcoreAg modulates antigen stability, immunogenicity, and antiviral efficacy. Methods: bRNA was removed from HBcoreAg by capsid disassembly, followed by reassembly in the absence or presence of specific nucleic acid-based adjuvants poly I:C or CpG. The morphology and structure of empty, bRNA-containing and adjuvant-loaded HBcoreAg were monitored by electron microscopy and nuclear magnetic resonance spectroscopy. Empty, bRNA-containing or adjuvant-loaded HBcoreAg were applied together with HBsAg and with or without nucleic acid-based external adjuvants within the TherVacB regimen in both wild-type and HBV-carrier mice. Results: While HBcoreAg retained its structure upon bRNA removal, its stability and immunogenicity decreased significantly. Loading HBcoreAg with nucleic acid-based adjuvants re-established stability of the capsid-like antigen. Immunization with poly I:C- or CpG-loaded HBcoreAg induced high antibody titers against co-administered HBsAg. When applied within the TherVacB regimen, they activated vigorous HBcoreAg- and HBsAg-specific T-cell responses in wild-type and HBV-carrier mice, requiring a significantly lower dose of adjuvant compared to externally added adjuvant. Finally, immunization with adjuvant-loaded HBcoreAg mixed with HBsAg led to long-term control of persistent HBV replication in the HBV-carrier mice. Conclusion: Adjuvant-loaded HBcoreAg retained capsid integrity and stability, was as immunogenic in vivo as externally adjuvanted HBcoreAg, requiring lower adjuvant levels, and supported immunity against co-administered, non-adjuvanted HBsAg. Thus, adjuvant-loaded HBcoreAg represents a promising novel platform for vaccine development. Impact and implications: Hepatitis B core antigen (HBcoreAg) recapitulates the capsid of the HBV that hosts the viral genome. Produced recombinantly, it is not infectious but emerges as a potent immunogen in vaccine development. In this preclinical study, we show that loading HBcoreAg with defined nucleic-acid-based adjuvants on the one hand stabilizes the HBcoreAg with standardized capsid content and, on the other hand, efficiently promotes the immunity of HBcoreAg and a co-administered antigen, allowing for reduced adjuvant doses. Therefore, adjuvant-loaded HBcoreAg not only serves as an encouraging option for therapeutic hepatitis B vaccines, but could also act as an efficient adjuvant delivery system for other types of vaccine.

2.
Aging (Albany NY) ; 16(5): 4250-4269, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38407978

RESUMO

Lei's formula (LSF), a traditional Chinese herbal remedy, is recognized for its remarkable clinical effectiveness in treating osteoarthritis (OA). Despite its therapeutic potential, the exact molecular mechanisms underlying LSF's action in OA have remained enigmatic. Existing research has shed light on the role of the mTOR signaling pathway in promoting chondrocyte senescence, a central factor in OA-related cartilage degeneration. Consequently, targeting mTOR to mitigate chondrocyte senescence presents a promising avenue for OA treatment. The primary objective of this study is to establish LSF's chondroprotective potential and confirm its anti-osteoarthritic efficacy through mTOR inhibition. In vivo assessments using an OA mouse model reveal substantial articular cartilage degeneration. However, LSF serves as an effective guardian of articular cartilage, evidenced by reduced subchondral osteosclerosis, increased cartilage thickness, improved surface smoothness, decreased OARSI scores, elevated expression of cartilage anabolic markers (Col2 and Aggrecan), reduced expression of catabolic markers (Adamts5 and MMP13), increased expression of the chondrocyte hypertrophy marker (Col10), and decreased expression of chondrocyte senescence markers (P16 and P21). In vitro findings demonstrate that LSF shields chondrocytes from H2O2-induced apoptosis, inhibits senescence, enhances chondrocyte differentiation, promotes the synthesis of type II collagen and proteoglycans, and reduces cartilage degradation. Mechanistically, LSF suppresses chondrocyte senescence through the mTOR axis, orchestrating the equilibrium between chondrocyte anabolism and catabolism, ultimately leading to reduced apoptosis and decelerated OA cartilage degradation. LSF holds significant promise as a therapeutic approach for OA treatment, offering new insights into potential treatments for this prevalent age-related condition.


Assuntos
Cartilagem Articular , Osteoartrite , Camundongos , Animais , Condrócitos/metabolismo , Peróxido de Hidrogênio/farmacologia , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Cartilagem Articular/metabolismo
3.
Org Biomol Chem ; 22(11): 2182-2186, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38390690

RESUMO

Three novel phragmalin-type limonoids, swieteliacates S-U (1-3), were isolated from Swietenia macrophylla leaves, alongside four previously identified limonoids (4-7). The structures, encompassing absolute configurations, were delineated through 1D and 2D NMR analyses, high-resolution mass spectrometry (HR-MS), and NMR and ECD calculations. Swieteliacate S (1) is a distinctive cryptate comprising a tricyclo[4.2.110,30.11,4]decane fragment and an additional five-membered oxygen ring. Compounds 3 and 5 exhibited inhibition rates of 26.08 ± 2.26% and 15.42 ± 3.66%, respectively, on triglyceride (TG) production in Hep G2 cells at 40 µM.


Assuntos
Limoninas , Meliaceae , Limoninas/química , Limoninas/farmacologia , Estrutura Molecular , Espectroscopia de Ressonância Magnética , Meliaceae/química
4.
Biomater Sci ; 12(6): 1573-1589, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38319143

RESUMO

Implant-associated infections are significant impediments to successful surgical outcomes, often resulting from persistent bacterial contamination. It has been hypothesized that bacteria can transfer electrons to semiconductors with comparable potential to the biological redox potential (BRP). Building on this concept, we developed an antibiotic-free bactericidal system, Co3O4/TiO2-Ti, capable of achieving real-time and sustainable bactericidal effects. Our study demonstrated that Co3O4/TiO2-Ti, possessing an appropriately set valence band, initiated charge transfer, reactive oxygen species (ROS) production, and membrane damage in adherent Staphylococcus aureus (S. aureus). Notably, in vivo experiments illustrated the remarkable antibacterial activity of Co3O4/TiO2-Ti, while promoting soft-tissue reconstruction and demonstrating excellent cytocompatibility. Transcriptomic analysis further revealed a down-regulation of aerobic respiration-associated genes and an up-regulation of ROS-associated genes in S. aureus in the presence of Co3O4/TiO2-Ti compared to Ti. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and gene set enrichment analysis (GSEA) identified alterations in respiratory metabolism, oxidative phosphorylation, and the synthesis of amino acid in S. aureus cultured on Co3O4/TiO2-Ti. Furthermore, when combined with near-infrared (NIR) irradiation and photothermal therapy (PTT), Co3O4/TiO2-Ti eliminated 95.71% of floating and adherent S. aureus in vitro. The findings suggest that this antibiotic-free strategy holds substantial promise in enhancing implant sterilization capabilities, thereby contributing to the prevention and treatment of bacterial infections through bandgap engineering of implants and NIR irradiation.


Assuntos
Cobalto , Óxidos , Terapia Fototérmica , Staphylococcus aureus , Espécies Reativas de Oxigênio , Elétrons , Antibacterianos/farmacologia , Titânio/química
5.
Phytomedicine ; 126: 155444, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367423

RESUMO

BACKGROUND: Stomach diseases have become global health concerns. Protoberberine alkaloids (PBAs) are a group of quaternary isoquinoline alkaloids from abundant natural sources and have been shown to improve gastric disorders in preclinical and clinical studies. The finding that PBAs exhibit low oral bioavailability but potent pharmacological activity has attracted great interest. PURPOSE: This review aims to provide a systematic review of the molecular mechanisms of PBAs in the treatment of gastric disorders and to discuss the current understanding of the pharmacokinetics and toxicity of PBAs. METHODS: The articles related to PBAs were collected from the Web of Science, Pubmed, and China National Knowledge Infrastructure databases using relevant keywords. The collected articles were screened and categorized according to their research content to focus on the gastroprotective effects, pharmacokinetics, and toxicity of PBAs. RESULTS: Based on the results of preclinical studies, PBAs have demonstrated therapeutic effects on chronic atrophic gastritis and gastric cancer by activating interleukin-4 (IL-4)/signal transducer and activator of transcription 6 (STAT6) pathway and suppressing transforming growth factor-beta 1 (TGF-ß1)/phosphoinositide 3-kinase (PI3K), Janus kinase-2 (JAK2)/signal transducers and activators of transcription 3 (STAT3), and mitogen-activated protein kinase (MAPK) pathways. The major PBAs exhibit similar pharmacokinetic properties, including rapid absorption, slow elimination, and low bioavailability. Notably, the natural organ-targeting property of PBAs may account for the finding of their low blood levels and high pharmacological activity. PBAs interact with other compounds, including conventional drugs and natural products, by modulation of metabolic enzymes and transporters. The potential tissue toxicity of PBAs should be emphasized due to their high tissue accumulation. CONCLUSION: This review highlights the gastroprotective effects, pharmacokinetics, and toxicity of PBAs and will contribute to the evaluation of drug properties and clinical translational studies of PBAs, accelerating their transfer from the laboratory to the bedside.


Assuntos
Alcaloides , Alcaloides de Berberina , Medicamentos de Ervas Chinesas , Fosfatidilinositol 3-Quinases , Alcaloides/farmacologia , Alcaloides/química , Alcaloides de Berberina/farmacologia , Medicamentos de Ervas Chinesas/farmacologia
6.
Elife ; 122024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236718

RESUMO

As the genome is organized into a three-dimensional structure in intracellular space, epigenomic information also has a complex spatial arrangement. However, most epigenetic studies describe locations of methylation marks, chromatin accessibility regions, and histone modifications in the horizontal dimension. Proper spatial epigenomic information has rarely been obtained. In this study, we designed spatial chromatin accessibility sequencing (SCA-seq) to resolve the genome conformation by capturing the epigenetic information in single-molecular resolution while simultaneously resolving the genome conformation. Using SCA-seq, we are able to examine the spatial interaction of chromatin accessibility (e.g. enhancer-promoter contacts), CpG island methylation, and spatial insulating functions of the CCCTC-binding factor. We demonstrate that SCA-seq paves the way to explore the mechanism of epigenetic interactions and extends our knowledge in 3D packaging of DNA in the nucleus.


Assuntos
Cromatina , Epigenômica , Cromatina/genética , Cromossomos , DNA , Sequências Reguladoras de Ácido Nucleico , Metilação de DNA
7.
ACS Biomater Sci Eng ; 10(1): 525-536, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38099722

RESUMO

Piezoelectric materials have received increasing attention in bone regeneration due to their prominent role in bioelectricity in bone homeostasis. This study aimed to develop bioactive barium titanate-chitosan-graphene oxide piezoelectric nanoparticles (BCG-NPs) to improve biocompatibility and stimulate bone repair. Butterfly loops, hysteresis loops, and in vitro microcurrent studies on BCG-NPs confirmed their good piezoelectric properties. BCG-NPs exhibited enhanced alkaline phosphatase activity, mineralized nodule formation, and expression of osteogenic-associated proteins and genes in human umbilical cord Wharton's jelly-derived mesenchymal stem cells by creating microelectric environments in response to noninvasive ultrasound stimulation. Further, BCG-NPs upregulated intracellular calcium ions via electrical stimulation. They acted synergistically with piezo-type mechanosensitive ion channel component 1 and calcium-permeable cation channel transient receptor potential vanilloid 4 to activate osteogenic differentiation. In conclusion, ultrasound-assisted BCG-NPs created a microelectric environment that putatively promoted bone repair in a noninvasive manner.


Assuntos
Cálcio , Osteogênese , Humanos , Osteogênese/genética , Vacina BCG , Biomimética , Regeneração Óssea
8.
Nucleic Acids Res ; 51(22): e112, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37941145

RESUMO

We presented an experimental method called FLOUR-seq, which combines BD Rhapsody and nanopore sequencing to detect the RNA lifecycle (including nascent, mature, and degrading RNAs) in cells. Additionally, we updated our HIT-scISOseq V2 to discover a more accurate RNA lifecycle using 10x Chromium and Pacbio sequencing. Most importantly, to explore how single-cell full-length RNA sequencing technologies could help improve the RNA velocity approach, we introduced a new algorithm called 'Region Velocity' to more accurately configure cellular RNA velocity. We applied this algorithm to study spermiogenesis and compared the performance of FLOUR-seq with Pacbio-based HIT-scISOseq V2. Our findings demonstrated that 'Region Velocity' is more suitable for analyzing single-cell full-length RNA data than traditional RNA velocity approaches. These novel methods could be useful for researchers looking to discover full-length RNAs in single cells and comprehensively monitor RNA lifecycle in cells.


Assuntos
Sequenciamento por Nanoporos , Análise de Sequência de RNA , Análise de Célula Única , Algoritmos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sequenciamento por Nanoporos/métodos , Análise de Sequência de RNA/métodos
9.
Mar Environ Res ; 191: 106124, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37586224

RESUMO

For marine animals living in estuarine, coastal, and intertidal areas, salinity changes and periodic hypoxia are typical stressors; however, how the varying salinity and dissolved oxygen affect the quality and nutrition of marine aquaculture species, such as oysters remains unknown. In this study, we evaluated the diel-cycling hypoxia under different salinities on fatty acid composition and lipid metabolism in oyster Crassostrea hongkongensis digestive glands. After 28 days of exposure, both hypoxia and elevated salinity caused a decrease in the saturated fatty acid (SFA)/polyunsaturated fatty acid (PUFA) ratio of C. hongkongensis, salinity mainly causes changes in C17:0, C17:1, C18:1n9, C20:1n9, C20:4n6, C21:5n3, C22:5n3, with high salinity being more damaging to the fatty acid fractions. Also, Hypoxia accelerates the synthesis of C18:1n9 and C20:4n6. Fatty acid synthase (FAS) synthesis is increased by reduced salinity or hypoxia, but Acetyl CoA carboxylase (ACC) only weakly promotes fatty acid synthesis. Under hypoxic conditions, the activity of both hepatic lipase (HL) and lipoprotein lipase activity (LPL) decreases, which is contrary to the results for dissolved oxygen. The increase in salinity under dissolved oxygen leads to a decrease in LPL activity and an increase in HL activity. Our findings highlighted that exposure to a combination of salinity and hypoxia stressors, can disrupt the protective mechanisms of the oyster and affect the function of its lipid metabolism. Therefore, long-term exposure to periodic hypoxia with salinity changes poses a risk to the nutritional quality of C. hongkongensis, affecting oyster aquaculture and the coastal ecosystem.

10.
J Biomed Mater Res A ; 111(11): 1808-1821, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37548424

RESUMO

Polyetheretherketone (PEEK) is a promising material for use in orthopedic implants, but its bio-inert character and lack of antibacterial activity limit its applications in bone repair. In the present study, considering the advantages of PEEK in self-initiated graft polymerization and of hydrogels in bone tissue engineering, we constructed a hydrogel coating (GPL) consisting of Gelatin methacryloyl (GelMA), methacrylamide-modified ε-poly-l-lysine (ε-PLMA) and Laponite on PEEK through UV-initiated crosslinking. The coating improved the hydrophilicity of PEEK, and the coating degraded slowly so that approximately 80% was retained after incubation in PBS for 8 weeks. In vitro studies revealed that as compared to culturing on PEEK, culturing on PEEK-GPL led to enhanced viability and adhesion of cultured human umbilical cord Wharton's jelly-derived mesenchymal stem cells (hWJ-MSCs). Due to the synergistic effect of the micron-scale three-dimensional surface and Laponite, PEEK-GPL exhibited a significantly improved induction of osteogenic differentiation of hWJ-MSCs compared to PEEK, as demonstrated by increased alkaline phosphatase activity, matrix mineralization, and expression of osteogenesis-related genes. Furthermore, PEEK-GPL showed antibacterial activity upon contact with Staphylococcus aureus and Escherichia coli, and this activity would be maintained before complete degradation of the hydrogel because the ε-PLMA was cross-linked covalently into the coating. Thus, PEEK-GPL achieved both osteogenesis and infection prevention in a single simple step, providing a feasible approach for the extensive use of PEEK in bone implants.


Assuntos
Osteogênese , Polilisina , Humanos , Polilisina/farmacologia , Hidrogéis/farmacologia , Polimerização , Polietilenoglicóis/farmacologia , Cetonas/farmacologia , Antibacterianos/farmacologia , Propriedades de Superfície
11.
Acta Neurochir (Wien) ; 165(10): 3077-3087, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37488398

RESUMO

BACKGROUND: Visual instruments are essential to ensure high-quality surgical outcomes for minimally invasive procedures and have gradually become the focus of research. Recently, a novel visual auxiliary instrument, a 3-dimensional exoscope (EX), has been applied for spinal surgery. However, its advantages over other auxiliary means (OAMs) in anterior cervical surgery need to be assessed. OBJECTIVE: To compare and evaluate the clinical outcomes of EX and OAMs in anterior cervical spine surgery using a meta-analysis and to provide the latest clinical evidence. METHODS: PubMed, Embase, Cochrane Library, Web of Science, CNKI, and Wanfang Database were systematically reviewed for relevant literature published prior to January 21, 2023. Two researchers independently screened the literature, extracted data, and assessed bias risk in the included literature. Review Manager software (version 5.4; the Cochrane Collaboration) was used to conduct the meta-analysis. RESULTS: five studies, one prospective and four retrospective cohort studies, with a total of 349 patients (154 in the EX group and 195 in the OAMs group) were included. A meta-analysis showed that compared to OAMs, EX-assisted anterior cervical spine surgery resulted in less intraoperative hemorrhage [WMD = -8.96, 95% CI (-14.21, -3.71), P = 0.0008]. Nevertheless, no significant differences in VAS scores, JOA scores, operation time, hospitalization time, and complication rate were observed between the two groups (P > 0.05). CONCLUSION: EX and OAMs are equally safe and effective for anterior cervical spine surgery; however, compared to OAMs, EX results in less intraoperative hemorrhage.


Assuntos
Vértebras Cervicais , Fusão Vertebral , Humanos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Estudos Retrospectivos , Estudos Prospectivos , Fusão Vertebral/métodos , Perda Sanguínea Cirúrgica , Resultado do Tratamento
12.
Sci Total Environ ; 893: 164836, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37321498

RESUMO

Nano-TiO2 can act as a vector to organic compounds, such as pentachlorophenol (PCP) posing a potential threat to the marine ecosystems. Studies showed that nano pollutant toxicity can be modulated by abiotic factors, but little is known about the potential influence of biotic stressors (such as predators) on the physiological responses to pollutants in marine organisms. We explored the effects of n-TiO2 and PCP on the mussel Mytilus coruscus in the presence of its natural predator, the swimming crab Portunus trituberculatus. Exposure to n-TiO2, PCP, and predation risk showed interactive effects on antioxidant and immune parameters of the mussels. Elevated activities of catalase (CAT), glutathione peroxidase (GPX), acid phosphatase (ACP) and alkaline phosphatase (AKP), suppressed activity of superoxide dismutase (SOD), lower levels of glutathione (GSH) and increased malondialdehyde (MDA) levels indicated dysregulation of the antioxidant system and immune stress induced by single PCP or n-TiO2 exposure. Integrated biomarker (IBR) response values showed the effect of PCP was concentration dependent. Of the two used n-TiO2 sizes (25 and 100 nm), larger particles induced higher antioxidant and immune disturbances indicating higher toxicity possibly due to higher bioavailability. Compared to single PCP exposure, the combination of n-TiO2 and PCP enhanced the imbalance of SOD/CAT and GSH/GPX and led to elevated oxidative lesions and activation of immune-related enzymes. Overall, the combined impacts of pollutants and biotic stress exhibited a greater magnitude of adverse effects on antioxidant defense and immune parameters in mussels. The toxicological effects of PCP were exacerbated in the presence of n-TiO2, and the deleterious impact of these stressors was further amplified under predator-induced risk after prolonged (28 days) exposure. However, the underlying physiological regulatory mechanisms governing the interplay of these stressors and predatory cues on mussels remain elusive, warranting further investigation.


Assuntos
Poluentes Ambientais , Mytilus , Pentaclorofenol , Poluentes Químicos da Água , Animais , Antioxidantes/metabolismo , Pentaclorofenol/toxicidade , Ecossistema , Comportamento Predatório , Mytilus/fisiologia , Glutationa , Superóxido Dismutase/metabolismo , Imunidade , Estresse Oxidativo , Poluentes Químicos da Água/toxicidade
13.
Environ Pollut ; 331(Pt 2): 121921, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37263564

RESUMO

Anthropologic activities caused frequent eutrophication in coastal and estuarine waters, resulting in diel-cycling hypoxia. Given global climate change, extreme weather events often occur, thus salinity fluctuation frequently breaks out in these waters. This study aimed to evaluate the combined effects of salinity and hypoxia on intestinal microbiota and digestive enzymes of Crassostrea hongkongensis. Specifically, we sequenced 16 S rRNA of intestinal microbiota and measured the digestive enzymes trypsin (TRS), lipase (LPS) and amylase (AMY) in oysters exposed for 28 days to three salinities (10, 25 and 35) and two dissolved oxygen conditions, normoxia (6 mg/L) and hypoxia (6 mg/L for 12 h, 2 mg/L for 12 h). Oysters in normoxia and salinity of 25 were treated as control. After 28-day exposure, for microbial components, Fusobacteriota, Firmicutes, Bacteroidota, Proteobacteria and Actinobacteriota comprised the majority for all experimental groups. Compared with the control group, the diversity and structure of intestinal microbiota tended to change in all treated groups. The species richness in C. hongkongensis intestine also changed. It was the most significant that high salinity increased Proteobacteria proportion while low salinity and hypoxia increased Fusobacteriota but decreased Proteobacteria, respectively. Additionally, Actinobacteriota was sensitive and changed under environmental stressor (P < 0.01). The prediction results on intestinal microbiota showed that, all functions of oysters were up-regulated to distinct degrees under low/high salinity with hypoxia. According to the KEGG prediction, cellular processes were more active and energy metabolism upregulated, indicating the adaptation of C. hongkongensis to environmental change. Periodical hypoxia and low/high salinity had complex effect on the digestive enzymes, in which the activity of TRS and LPS decreased while AMY increased. High/low salinity and periodical hypoxia can change the secretion of digestive enzymes and influence intestinal microbial diversity and species richness of C. hongkongensis, deducing the chronic adverse effects on the digestive physiology in long-term exposure.


Assuntos
Crassostrea , Microbioma Gastrointestinal , Animais , Crassostrea/metabolismo , Salinidade , Lipopolissacarídeos , Hipóxia
14.
Front Microbiol ; 14: 1108651, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37032874

RESUMO

Recently, several reports showed that n-alkanes were abundant in the hadal zone, suggesting that n-alkanes could be an important source of nutrients for microorganisms in hadal ecosystems. To date, most of the published studies on the microbial capacity to degrade hydrocarbons were conducted only at atmospheric temperature and pressure (0.1 MPa), and little is known about whether and which microbes could utilize n-alkanes at in situ environmental conditions in the hadal zone, including low temperature and high hydrostatic pressure (especially >30 MPa). In this study, a piezotolerant bacterium, strain C2-1, was isolated from a Mariana Trench sediment at depth of 5,800 m. Strain C2-1 was able to grow at in situ temperature (4°C) and pressure (58 MPa) with n-alkanes as the sole carbon source. Phylogenetically, strain C2-1 and related strains (TMPB967, ST750PaO-4, IMCC1826, and TTBP476) should be classified into the genus Venatorbacter. Metagenomic analysis using ~5,000 publicly available datasets showed that Venatorbacter has a wide environmental distribution in seawater (38), marine sediments (3), hydrothermal vent plumes (2), Antarctic ice (1), groundwater (13), and marine sponge ecosystems (1). Most Venatorbacter species are non-obligate n-alkane degraders that could utilize, at a minimal, C16-C18 n-alkanes, as well as other different types of carbon substrates, including carbohydrates, amino acids, peptides, and phospholipids. The type II secretion system, extracellular proteases, phospholipase, and endonuclease of Venatorbacter species were robustly expressed in the metatranscriptomes of deep-sea hydrothermal vents, suggesting their important contribution to secondary productivity by degrading extracellular macromolecules. The identification of denitrifying genes suggested a genus-specific ecological potential that allowed Venatorbacter species to be active in anoxic environments, e.g., the oxygen-minimal zone (OMZ) and the deeply buried marine sediments. Our results show that Venatorbacter species are responsible for the degradation of hydrocarbon and extracellular macromolecules, suggesting that they may play an important role in the biogeochemistry process in the Trench ecosystems.

15.
Sci Total Environ ; 881: 163499, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37062322

RESUMO

Nano­titanium dioxide (nTiO2) is a widely used nanomaterial posing potential ecological risk for marine ecosystems that might be enhanced by elevated temperatures such as expected during climate change. nTiO2 may affect benthic filter feeders like mussels through waterborne exposures and via food chain due to the adsorption on/in algae. Mussel byssus are proteinaceous fibers secreted by byssal glands of the mussels for attachment. Byssus production and mechanical properties are sensitive to environmental stressors but the combined effects of warming and nTiO2 on byssus performance of mussels are unclear hampering our understanding of the predation and dislodgement risk of mussels under the multiple stressor scenarios. We explored the effects of a short-term (14-day) single and combined exposures to warming (28 °C) and 100 µg L-1 nTiO2 (including food co-exposure) on the byssus performance of the thick shell mussel Mytilus coruscus. The mechanical strength (measured as the breaking force) of the byssal threads was impaired by warming and nTiO2 (including food co-exposure), but the number and length of the byssal threads were increased. The mRNA expression levels of mussel foot proteins (mfp-3, mfp-5) and pre-collagens (preCOL-D, preCOL-P, preCOL-NG) were up-regulated to varying degrees, with the strongest effects induced by warming. This indicates that the physiological and molecular mechanisms of byssus secretion are plastic. However, downregulation of the mRNA expression of preCOL-D and preCOL-P under the combined warming and nTiO2 exposures indicate the limits of these plasticity mechanisms and suggest that the attachment ability and survival of the mussels may be impaired if the pollution or temperature conditions further deteriorate.


Assuntos
Ecossistema , Mytilus , Animais , Exposição Dietética , Mytilus/fisiologia , Proteínas , Oceanos e Mares , RNA Mensageiro
16.
Microorganisms ; 11(3)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36985204

RESUMO

Recent studies reported that highly abundant alkane content exists in the ~11,000 m sediment of the Mariana Trench, and a few key alkane-degrading bacteria were identified in the Mariana Trench. At present, most of the studies on microbes for degrading hydrocarbons were performed mainly at atmospheric pressure (0.1 MPa) and room temperature; little is known about which microbes could be enriched with the addition of n-alkanes under in-situ environmental pressure and temperature conditions in the hadal zone. In this study, we conducted microbial enrichments of sediment from the Mariana Trench with short-chain (SCAs, C7-C17) or long-chain (LCAs, C18-C36) n-alkanes and incubated them at 0.1 MPa/100 MPa and 4 °C under aerobic or anaerobic conditions for 150 days. Microbial diversity analysis showed that a higher microbial diversity was observed at 100 MPa than at 0.1 MPa, irrespective of whether SCAs or LCAs were added. Non-metric multidimensional scaling (nMDS) and hierarchical cluster analysis revealed that different microbial clusters were formed according to hydrostatic pressure and oxygen. Significantly different microbial communities were formed according to pressure or oxygen (p < 0.05). For example, Gammaproteobacteria (Thalassolituus) were the most abundant anaerobic n-alkanes-enriched microbes at 0.1 MPa, whereas the microbial communities shifted to dominance by Gammaproteobacteria (Idiomarina, Halomonas, and Methylophaga) and Bacteroidetes (Arenibacter) at 100 MPa. Compared to the anaerobic treatments, Actinobacteria (Microbacterium) and Alphaproteobacteria (Sulfitobacter and Phenylobacterium) were the most abundant groups with the addition of hydrocarbon under aerobic conditions at 100 MPa. Our results revealed that unique n-alkane-enriched microorganisms were present in the deepest sediment of the Mariana Trench, which may imply that extremely high hydrostatic pressure (100 MPa) and oxygen dramatically affected the processes of microbial-mediated alkane utilization.

17.
Genome Biol ; 24(1): 61, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991510

RESUMO

Epigenetic modifications of histones are associated with development and pathogenesis of disease. Existing approaches cannot provide insights into long-range interactions and represent the average chromatin state. Here we describe BIND&MODIFY, a method using long-read sequencing for profiling histone modifications and transcription factors on individual DNA fibers. We use recombinant fused protein A-M.EcoGII to tether methyltransferase M.EcoGII to protein binding sites to label neighboring regions by methylation. Aggregated BIND&MODIFY signal matches bulk ChIP-seq and CUT&TAG. BIND&MODIFY can simultaneously measure histone modification status, transcription factor binding, and CpG 5mC methylation at single-molecule resolution and also quantifies correlation between local and distal elements.


Assuntos
Eucariotos , Histonas , Eucariotos/genética , Histonas/metabolismo , Cromatina , Metilação , DNA/metabolismo , Metilação de DNA
18.
Sensors (Basel) ; 23(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36772577

RESUMO

To achieve automatic disc cutter replacement of shield machines, measuring the accurate pose of the disc cutter holder by machine vision is crucial. However, under polluted and restricted illumination conditions, achieving pose estimation by vision is a great challenge. This paper proposes a line-features-based pose estimation method for the disc cutter holder of the shield machine by using a monocular camera. For the blurring effect of rounded corners on the image edge, a rounded edge model is established to obtain edge points that better match the 3D model of the workpiece. To obtain the edge search box corresponding to each edge, a contour separation method based on an adaptive threshold region growing method is proposed. By preprocesses on the edge points of each edge, the efficiency and the accuracy of RANSAC linear fitting are improved. The experimental result shows that the proposed pose estimation method is highly reliable and can meet the measurement accuracy requirements in practical engineering applications.

19.
Microb Ecol ; 86(2): 1200-1212, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36068360

RESUMO

Intestinal microbes are essential participants in host vital activities. The composition of the microbiota is closely related to the environmental factors. Predator presence may impact on intestinal microbiota of prey. In the present study, stone crab Charybdis japonica was used as potential predator, an external stress on mussel Mytilus coruscus, to investigate the intestinal microbiota alteration in M. coruscus. We set up two forms of predator presence including free crab and trapped crab, with a blank treatment without crab. The composition of intestinal microbiota in mussels among different treatments showed significant differences by 16S rRNA techniques. The biodiversity increased with trapped crab presence, but decreased with free crab presence. Neisseria, the most abundant genus, fell with the presence of crabs. Besides, the Arcobacter, a kind of pathogenic bacteria, increased with free crab presence. Regarding PICRUTs analysis, Environmental Information Processing, Genetic Information Processing and Metabolism showed differences in crab presence treatments compared with the blank, with a bit higher in the presence of free crab than trapped crab. In conclusion, trapped crab effects activated the metabolism and immunity of the intestinal flora, but free crabs made mussels more susceptible to disease and mortality, corresponding to the decreased biodiversity and the increased Arcobacter in their intestine.


Assuntos
Braquiúros , Microbioma Gastrointestinal , Mytilus , Animais , Humanos , RNA Ribossômico 16S/genética , Biodiversidade
20.
Orthop Surg ; 14(12): 3358-3366, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36419319

RESUMO

OBJECTIVE: Hook plate fixation is the traditional method for treating distal clavicle fractures. However, in recent years, locked plate applications have emerged as a promising treatment method. This study aimed to compare the short- and mid-term clinical efficacy of anatomical locked plate fixation with coracoclavicular ligament augmentation using anchor nails to that of hook plate fixation in treating distal clavicle fractures. METHODS: This was a retrospective single-center cohort study investigating patients with distal clavicle fractures treated between January 2016 and February 2019 in Zhongnan Hospital of Wuhan University. Fifty-nine eligible patients who underwent either anatomical locked plate fixation with coracoclavicular ligament augmentation using anchor nails (LPF&CLA group; 20 patients) or clavicle hook plate fixation (CHPF group; 39 patients) were included. The visual analog scale (VAS) and Constant-Murley shoulder scores were used to assess shoulder function. In addition, the coracoclavicular distance between the affected and unaffected shoulders (ΔCC distance) was measured to assess the reduction. Patients were followed up at 3 months, 6 months, and 1 year postoperatively. The comparisons between the two groups were made using Student's t-test, chi-square test, or Fisher's exact test, if appropriate. RESULTS: Preoperative VAS scores were similar in both groups. At 3- and 6-month follow-up, the VAS score was significantly higher in the CHPF group than in the LPF&CLA group. In contrast, the Constant-Murley shoulder score was significantly lower in the CHPF group than in the LPF&CLA group. When the hook plates were removed, there was no statistical difference in both VAS (0.2 ± 0.4 in LPF&CLA group vs. 0.5 ± 0.5 in CHPF group, p = 0.05) and Constant-Murley shoulder (96.1 ± 3.1 in LPF&CLA group vs. 93.8 ± 5.2 in CHPF group, p = 0.08) scores at the last follow-up. Postoperatively, the ΔCC distance was 2.37 ± 1.93 mm in the LPF&CLA group and -1.56 ± 1.34 mm in the CHPF group. One year after surgery, ΔCC distance increased to 3.96 ± 1.17 mm in the LPF&CLA group and to -0.89 ± 1.39 mm in the CHPF group. CONCLUSION: For distal clavicle fractures in which the coracoclavicular ligament is disrupted, anatomical locked plate fixation with coracoclavicular ligament augmentation achieved better functional recovery and less pain than hook plate fixation at the 6-month follow-up. However, the hook plate provided better reduction throughout the follow-up period and shoulder pain could be relieved using removal surgery. Therefore, locked plates with coracoclavicular ligament augmentation favors post-surgery pain relief while harvesting similar functional outcomes to hook plate fixation.


Assuntos
Ligamentos , Humanos , Estudos de Coortes , Estudos Retrospectivos
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