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1.
Sci Adv ; 10(21): eadj8184, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38781332

RESUMO

Sinking particles are a critical conduit for the transport of surface microbes to the ocean's interior. Vertical connectivity of phylogenetic composition has been shown; however, the functional vertical connectivity of microbial communities has not yet been explored in detail. We investigated protein and taxa profiles of both free-living and particle-attached microbial communities from the surface to 3000 m depth using a combined metaproteomic and 16S rRNA amplicon sequencing approach. A clear compositional and functional vertical connectivity of microbial communities was observed throughout the water column with Oceanospirillales, Alteromonadales, and Rhodobacterales as key taxa. The surface-derived particle-associated microbes increased the expression of proteins involved in basic metabolism, organic matter processing, and environmental stress response in deep waters. This study highlights the functional vertical connectivity between surface and deep-sea microbial communities via sinking particles and reveals that a considerable proportion of the deep-sea microbes might originate from surface waters and have a major impact on the biogeochemical cycles in the deep sea.


Assuntos
Microbiota , Oceanos e Mares , Filogenia , RNA Ribossômico 16S , Água do Mar , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Bactérias/genética , Bactérias/classificação
2.
World J Diabetes ; 15(3): 552-564, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38591089

RESUMO

BACKGROUND: The association of single nucleotide polymorphism of KCNQ1 gene rs2237895 with type 2 diabetes mellitus (T2DM) is currently controversial. It is unknown whether this association can be gene realized across different populations. AIM: To determine the association of KCNQ1 rs2237895 with T2DM and provide reliable evidence for genetic susceptibility to T2DM. METHODS: We searched PubMed, Embase, Web of Science, Cochrane Library, Medline, Baidu Academic, China National Knowledge Infrastructure, China Biomedical Liter-ature Database, and Wanfang to investigate the association between KCNQ1 gene rs2237895 and the risk of T2DM up to January 12, 2022. Review Manager 5.4 was used to analyze the association of the KCNQ1 gene rs2237895 polymorphism with T2DM and to evaluate the publication bias of the selected literature. RESULTS: Twelve case-control studies (including 11273 cases and 11654 controls) met our inclusion criteria. In the full population, allelic model [odds ratio (OR): 1.19; 95% confidence interval (95%CI): 1.09-1.29; P < 0.0001], recessive model (OR: 1.20; 95%CI: 1.11-1.29; P < 0.0001), dominant model (OR: 1.27. 95%CI: 1.14-1.42; P < 0.0001), and codominant model (OR: 1.36; 95%CI: 1.15-1.60; P = 0.0003) (OR: 1.22; 95%CI: 1.10-1.36; P = 0.0002) indicated that the KCNQ1 gene rs2237895 polymorphism was significantly correlated with susceptibility to T2DM. In stratified analysis, this association was confirmed in Asian populations: allelic model (OR: 1.25; 95%CI: 1.13-1.37; P < 0.0001), recessive model (OR: 1.29; 95%CI: 1.11-1.49; P = 0.0007), dominant model (OR: 1.35; 95%CI: 1.20-1.52; P < 0.0001), codominant model (OR: 1.49; 95%CI: 1.22-1.81; P < 0.0001) (OR: 1.26; 95%CI: 1.16-1.36; P < 0.0001). In non-Asian populations, this association was not significant: Allelic model (OR: 1.06, 95%CI: 0.98-1.14; P = 0.12), recessive model (OR: 1.04; 95%CI: 0.75-1.42; P = 0.83), dominant model (OR: 1.06; 95%CI: 0.98-1.15; P = 0.15), codominant model (OR: 1.08; 95%CI: 0.82-1.42; P = 0.60. OR: 1.15; 95%CI: 0.95-1.39; P = 0.14). CONCLUSION: KCNQ1 gene rs2237895 was significantly associated with susceptibility to T2DM in an Asian population. Carriers of the C allele had a higher risk of T2DM. This association was not significant in non-Asian populations.

3.
J Ethnopharmacol ; 325: 117897, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38336180

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bushen Quhan Zhiwang decoction (BQZD), a formula in traditional Chinese medicine (TCM), effectively delays bone destruction in rheumatoid arthritis (RA) patients. However, its chemical constituents, absorbed components, and metabolites remain unrevealed, and its mechanism in treating bone destruction in RA needs further investigation. AIM OF THE STUDY: Our objective is to identify the chemical constituents, absorbed components, and metabolites of BQZD and explore the potential mechanisms of BQZD in treating bone destruction in RA. MATERIALS AND METHODS: This study systematically identified the chemical constituents, absorbed components, and metabolites of BQZD using ultra-performance liquid chromatography with Q-Exactive Orbitrap mass spectrometry combined with parallel reaction monitoring. The absorbed components and metabolites were subjected to network pharmacology analysis to predict the potential mechanisms of BQZD in treating bone destruction in RA. The in vivo anti-osteoclastogenic and underlying mechanism were further verified in collagen-induced arthritis (CIA) rats. RESULTS: A total of 182 compounds were identified in BQZD, 27 of which were absorbed into plasma and organs and 42 metabolites were identified in plasma and organs. The KEGG analysis revealed that MAPK signaling pathway was highly prioritized. BQZD treatment attenuated paw swelling and the arthritis index; suppressed synovial hyperplasia, bone destruction, and osteoclast differentiation; and inhibited the levels of TNF-α, IL-1ß, and IL-6 in CIA rats. Mechanically, BQZD significantly decreased the protein expression levels of TRAF6, NFATc1, p-JNK, and p-p38, which might be related to 9 absorbed components and 1 metabolite. CONCLUSION: This study revealed the key active components and metabolites of BQZD. BQZD exhibits bone-protective effects via TRAF6/p38/JNK MAPK pathway, which may be associated with 9 absorbed components and 1 metabolite.


Assuntos
Artrite Experimental , Artrite Reumatoide , Medicamentos de Ervas Chinesas , Humanos , Ratos , Animais , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Farmacologia em Rede , Fator 6 Associado a Receptor de TNF , Artrite Reumatoide/tratamento farmacológico , Medicina Tradicional Chinesa , Artrite Experimental/tratamento farmacológico
4.
Methods ; 220: 106-114, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37972913

RESUMO

Discovering new indications for existing drugs is a promising development strategy at various stages of drug research and development. However, most of them complete their tasks by constructing a variety of heterogeneous networks without considering available higher-order connectivity patterns in heterogeneous biological information networks, which are believed to be useful for improving the accuracy of new drug discovering. To this end, we propose a computational-based model, called SFRLDDA, for drug-disease association prediction by using semantic graph and function similarity representation learning. Specifically, SFRLDDA first integrates a heterogeneous information network (HIN) by drug-disease, drug-protein, protein-disease associations, and their biological knowledge. Second, different representation learning strategies are applied to obtain the feature representations of drugs and diseases from different perspectives over semantic graph and function similarity graphs constructed, respectively. At last, a Random Forest classifier is incorporated by SFRLDDA to discover potential drug-disease associations (DDAs). Experimental results demonstrate that SFRLDDA yields a best performance when compared with other state-of-the-art models on three benchmark datasets. Moreover, case studies also indicate that the simultaneous consideration of semantic graph and function similarity of drugs and diseases in the HIN allows SFRLDDA to precisely predict DDAs in a more comprehensive manner.


Assuntos
Algoritmos , Semântica , Serviços de Informação
5.
BMC Bioinformatics ; 24(1): 451, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030973

RESUMO

BACKGROUND: As an important task in bioinformatics, clustering analysis plays a critical role in understanding the functional mechanisms of many complex biological systems, which can be modeled as biological networks. The purpose of clustering analysis in biological networks is to identify functional modules of interest, but there is a lack of online clustering tools that visualize biological networks and provide in-depth biological analysis for discovered clusters. RESULTS: Here we present BioCAIV, a novel webserver dedicated to maximize its accessibility and applicability on the clustering analysis of biological networks. This, together with its user-friendly interface, assists biological researchers to perform an accurate clustering analysis for biological networks and identify functionally significant modules for further assessment. CONCLUSIONS: BioCAIV is an efficient clustering analysis webserver designed for a variety of biological networks. BioCAIV is freely available without registration requirements at http://bioinformatics.tianshanzw.cn:8888/BioCAIV/ .


Assuntos
Biologia Computacional , Software , Análise por Conglomerados
6.
Cell Death Dis ; 14(11): 743, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968261

RESUMO

BRISC (BRCC3 isopeptidase complex) is a deubiquitinating enzyme that has been linked with inflammatory processes, but its role in liver diseases and the underlying mechanism are unknown. Here, we investigated the pathophysiological role of BRISC in acute liver failure using a mice model induced by D-galactosamine (D-GalN) plus lipopolysaccharide (LPS). We found that the expression of BRISC components was dramatically increased in kupffer cells (KCs) upon LPS treatment in vitro or by the injection of LPS in D-GalN-sensitized mice. D-GalN plus LPS-induced liver damage and mortality in global BRISC-null mice were markedly attenuated, which was accompanied by impaired hepatocyte death and hepatic inflammation response. Constantly, treatment with thiolutin, a potent BRISC inhibitor, remarkably alleviated D-GalN/LPS-induced liver injury in mice. By using bone marrow-reconstituted chimeric mice and cell-specific BRISC-deficient mice, we demonstrated that KCs are the key effector cells responsible for protection against D-GalN/LPS-induced liver injury in BRISC-deficient mice. Mechanistically, we found that hepatic and circulating levels of TNF-α, IL-6, MCP-1, and IL-1ß, as well as TNF-α- and MCP-1-producing KCs, in BRISC-deleted mice were dramatically decreased as early as 1 h after D-GalN/LPS challenge, which occurred prior to the elevation of the liver injury markers. Moreover, LPS-induced proinflammatory cytokines production in KCs was significantly diminished by BRISC deficiency in vitro, which was accompanied by potently attenuated NF-κB activation. Restoration of NF-κB activation by two small molecular activators of NF-κB p65 effectively reversed the suppression of cytokines production in ABRO1-deficient KCs by LPS. In conclusion, BRISC is required for optimal activation of NF-κB-mediated proinflammatory cytokines production in LPS-treated KCs and contributes to acute liver injury. This study opens the possibility to develop new strategies for the inhibition of KCs-driven inflammation in liver diseases.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Animais , Camundongos , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Células de Kupffer/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fígado/metabolismo , Inflamação/metabolismo , Galactosamina , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo
7.
J Chromatogr Sci ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37873817

RESUMO

Fructus Corni (F. Corni) is the dried mature pulp of Cornus officinalis Sieb. et Zucc.(Cornaceae), which is rich in iridoids. In this study, a simple, sensitive and rapid UPLC-MS/MS method was developed for the simultaneous determination of 13 iridoid glycosides of F. Corni from different areas. Specifically, we included five new compounds (cornusdiridoid C, cornusdiridoid E, cornusdiridoid F, 3'',5''-dehydroxycornuside and 2'-O-p-coumaroyl-kingiside) and isomers (2'-O-p-E-coumaroylloganin and 2'-O-p-Z-coumaroylloganin) for the first time in the quality markers of F. Corni. A total of 13 compounds and two pairs of isomers were well isolated and tested within just 14 min. All calibration curves showed good linear regression (r2 ≥ 0.99) within the tested concentration ranges. The limit of detection and limit of quantification were in the range of 0.19-1.90 and 0.38-3.76 ng/mL, respectively. The intra-day and inter-day precision were <3.21% and 12.49%, the RSD values of repeatability did not exceed 6.81% and the average recoveries were 90.95-113.59% for the analytes. All iridoid glycosides stabilized within 12 h (RSD < 10.99%). This method has been successfully applied to the quality evaluation of crude and processed F. Corni from different areas. The determination of characteristic iridoid glycosides and isomers will provide a more reliable and comprehensive method for the evaluation of F. Corni.

8.
Phytomedicine ; 120: 155061, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37689035

RESUMO

BACKGROUND: The extension of average life expectancy and the aggravation of population aging have become the inevitable trend of human development. In an aging society, various problems related to medical care for the elderly have become increasingly prominent. However, most of the age-related diseases have the characteristics of multiple diseases at the same time, prone to complications, and atypical clinical manifestations, which bring great difficulties to its treatment. Galangin (3,5,7-trihydroxyflavone) is a natural active compound extracted from the root of Alpinia officinarum Hance (Zingiberaceae). Recently, many studies have shown that galangin has potential advantages in the treatment of neurodegenerative diseases and cardiovascular and cerebrovascular diseases, which are common in the elderly. In addition, it also showed that galangin had prospective activities in the treatment of tumor, diabetes, liver injury, asthma and arthritis. PURPOSE: This review aims to systematically summarize and discuss the effects and the underlying mechanism of galangin in the treatment of age-related diseases. METHODS: We searched PubMed, SciFinder, Web of Science and CNKI literature database resources, combined with the keywords "galangin", "neurodegenerative disease", "tumor", "diabetes", "pharmacological activity", "drug combination", "pharmacokinetics", "drug delivery system" and "safety", and comprehensively reviewed the pharmacological activities and mechanism of galangin in treating age-related diseases. RESULTS: According to the previous studies on galangin, the anti-neurodegenerative activity, cardiovascular and cerebrovascular protective activity, anti-tumor activity, anti-diabetes activity, anti-arthritis activity, hepatoprotective activity and antiasthmatic activity of galangin were discussed, and the related mechanisms were classified and summarized in detail. In addition, the drug combination, pharmacokinetics, drug delivery system and safety of galangin were furtherly discussed. CONCLUSIONS: This review will provide reference for galangin in the treatment of age-related diseases. Meanwhile, further experimental research and long-term clinical trials are needed to determine the therapeutic safety and efficacy of galangin.


Assuntos
Artrite , Asma , Flavonas , Idoso , Humanos , Estudos Prospectivos , Envelhecimento
9.
Sci Total Environ ; 897: 165374, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37422230

RESUMO

Fungi represent the dominant eukaryotic group of organisms in anoxic marine sedimentary ecosystems, ranging from a few centimeters to ~ 2.5 km below seafloor. However, little is known about how fungi can colonize anaerobic subseafloor environments for tens of millions of years and whether they play a role in elemental biogeochemical cycles. Based on metabolite detection, isotope tracer and gene analysis, we examined the anaerobic nitrogen conversion pathways of 19 fungal species (40 strains) isolated from1.3 to 2.5 km coal-bearing sediments below seafloor. Our results show for the first time that almost all fungi possess anaerobic denitrification, dissimilatory nitrate reduction to ammonium (DNRA), and nitrification pathways, but not anaerobic ammonium oxidation (anammox). Moreover, the distribution of fungi with different nitrogen-conversion abilities in subseafloor sediments was mainly determined by in situ temperature, CaCO3, and inorganic carbon contents. These findings suggest that fungi have multiple nitrogen transformation processes to cope with their requirements for a variety of nitrogen sources in nutrient deficient anaerobic subseafloor sedimentary environments.


Assuntos
Compostos de Amônio , Ecossistema , Nitrogênio/análise , Nitratos/análise , Compostos de Amônio/metabolismo , Fungos/metabolismo , Oxirredução , Desnitrificação
10.
BMC Psychiatry ; 23(1): 367, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231397

RESUMO

BACKGROUND: This study explored the feasibility of using EEG gamma-band (30-49 Hz) power as an index of cue-elicited craving in METH-dependent individuals. METHODS: Twenty-nine participants dependent on methamphetamine (METH) and 30 healthy participants were instructed to experience a METH-related virtual reality (VR) social environment. RESULTS: Individuals with METH dependence showed significantly stronger self-reported craving and higher gamma power in a VR environment than healthy individuals. In the METH group, the VR environment elicited a significant increase in gamma power compared with the resting state. The METH group then received a VR counterconditioning procedure (VRCP), which was deemed useful in suppressing cue-induced reactivity. After VRCP, participants showed significantly lower self-reported craving scores and gamma power when exposed to drug-related cues than the first time. CONCLUSIONS: These findings suggest that the EEG gamma-band power may be a marker of cue-induced reactivity in patients with METH dependence.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas , Metanfetamina , Humanos , Fissura , Sinais (Psicologia) , Eletroencefalografia
11.
Sci Total Environ ; 869: 161846, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36709898

RESUMO

Phaeocystis is a globally distributed Prymnesiophyte genus and usually forms massive harmful colony blooms, which impact marine ecosystem, mariculture, human health, and even threaten coastal nuclear power plant safety. However, the mechanisms behind the colony formation from the solitary cells remain poorly understood. Here, we investigated metabolic processes of both solitary and non-flagellated colonial cells of Phaeocystis globosa at different colony bloom stages in the subtropical Beibu Gulf using a metaproteomic approach. Temperature was significantly correlated with Phaeocystis colony bloom formation, and the flagellated motile solitary cells with abundant flagellum-associated proteins, such as tubulin and dynein, were the exclusive cellular morphotype at the solitary cell stage featured with temperatures ≥21 °C. When the temperature decreased to <21 °C, tiny colonies appeared and the flagellum-associated proteins were down-regulated in both solitary and non-flagellated colonial cells, while proteins involved in biosynthesis, chain polymerization and aggregation of glycosaminoglycan (GAG), a key constituent of gelatinous matrix, were up-regulated, indicating the central role of active GAG biosynthesis during the colony formation. Furthermore, light utilization, carbon fixation, nitrogen assimilation, and amino acid and protein synthesis were also enhanced to provide sufficient energy and substrates for GAG biosynthesis. This study highlighted that temperature induced re-allocation of energy and substances toward GAG biosynthesis is essential for colony bloom formation of P. globosa.


Assuntos
Haptófitas , Humanos , Ecossistema , Temperatura , Alimentos , Proliferação Nociva de Algas
12.
J Cardiovasc Pharmacol ; 81(1): 85-92, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36027482

RESUMO

ABSTRACT: Salidroside has anti-inflammatory and antiatherosclerotic effects, and mitochondrial homeostasis imbalance is closely related to cardiovascular disease. The aim of this study was to investigate the effect of salidroside on mitochondrial homeostasis after macrophage polarization and elucidate its possible mechanism against atherosclerosis. RAW264.7 cells were stimulated with 1 µg·mL -1 Lipopolysaccharide and 50 ng·mL -1 IFN-γ establish M1 polarization and were also pretreated with 400 µM salidroside. The relative expression of proinflammatory genes was detected by RT-PCR whereas that of mitochondrial homeostasis-related proteins and nuclear factor kappa-B (NF-κB) was detected by WB. Levels of intracellular reactive oxygen species (ROS), mitochondrial membrane potential, and mass were measured by chemifluorescence whereas that of NF-κB nuclear translocation was detected by immunofluorescence. Compared with the Mφ group, the M1 group demonstrated increased mRNA expression of interleukin-1ß , inductible nitric oxide synthase (iNOS), and tumor necrosis factor-α ; increased protein expression of iNOS, NOD-like receptor protein 3, putative kinase 1 , and NF-κB p65 but decreased protein expression of MFN2, Tom20, and PGC-1α; decreased mitochondrial membrane potential and mass; and increased ROS levels and NF-κB p65 nuclear translocation. Salidroside intervention decreased mRNA expression of interleukin-1ß and tumor necrosis factor-α compared with the M1 group but did not affect that of iNOS. Furthermore, salidroside intervention prevented the changes in protein expression, mitochondrial membrane potential and mass, ROS levels, and NF-κB p65 nuclear translocation observed in the M1 group. In summary, salidroside ultimately inhibits M1 macrophage polarization and maintains mitochondrial homeostasis after macrophage polarization by increasing mitochondrial membrane potential, decreasing ROS levels, inhibiting NF-κB activation, and in turn regulating the expression of proinflammatory factors and mitochondrial homeostasis-associated proteins.


Assuntos
NF-kappa B , Fator de Necrose Tumoral alfa , NF-kappa B/metabolismo , Interleucina-1beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Macrófagos , Lipopolissacarídeos/farmacologia , Óxido Nítrico Sintase/metabolismo , Homeostase , RNA Mensageiro/metabolismo
13.
Front Cardiovasc Med ; 9: 959955, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093159

RESUMO

Long non-coding RNA (lncRNAs) are longer than 200 nucleotides and cannot encode proteins but can regulate the expression of genes through epigenetic, transcriptional, and post-transcriptional modifications. The pathophysiology of smooth muscle cells can lead to many vascular diseases, and studies have shown that lncRNAs can regulate the phenotypic conversion of smooth muscle cells so that smooth muscle cells proliferate, migrate, and undergo apoptosis, thereby affecting the development and prognosis of vascular diseases. This review discusses the molecular mechanisms of lncRNA as a signal, bait, stent, guide, and other functions to regulate the phenotypic conversion of vascular smooth muscle cells, and summarizes the role of lncRNAs in regulating vascular smooth muscle cells in atherosclerosis, hypertension, aortic dissection, vascular restenosis, and aneurysms, providing new ideas for the diagnosis and treatment of vascular diseases.

14.
Zool Res ; 43(3): 380-390, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35362675

RESUMO

Maternal sleep deprivation (MSD) is a global public health problem that affects the physical and mental development of pregnant women and their newborns. The latest research suggests that sleep deprivation (SD) disrupts the gut microbiota, leading to neuroinflammation and psychological disturbances. However, it is unclear whether MSD affects the establishment of gut microbiota and neuroinflammation in the newborns. In the present study, MSD was performed on pregnant Sprague-Dawley rats in the third trimester of pregnancy (gestational days 15-21), after which intestinal contents and brain tissues were collected from offspring at different postnatal days (P1, P7, P14, and P56). Based on microbial profiling, microbial diversity and richness increased in pregnant rats subjected to MSD, as reflected by the significant increase in the phylum Firmicutes. In addition, microbial dysbiosis marked by abundant Firmicutes bacteria was observed in the MSD offspring. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) showed that the expression levels of proinflammatory cytokines interleukin 1ß (IL-1ß) and tumor necrosis factor α (TNF-α) were significantly higher in the MSD offspring at adulthood (P56) than in the control group. Through Spearman correlation analysis, IL-1ß and TNF-α were also shown to be positively correlated with Ruminococcus_1 and Ruminococcaceae_UCG-005 at P56, which may determine the microbiota-host interactions in MSD-related neuroinflammation. Collectively, these results indicate that MSD changes maternal gut microbiota and affects the establishment of neonatal gut microbiota, leading to neuroinflammation in MSD offspring. Therefore, understanding the role of gut microbiota during physiological development may provide potential interventions for cognitive dysfunction in MSD-impacted offspring.


Assuntos
Microbioma Gastrointestinal , Doenças dos Roedores , Animais , Disbiose/etiologia , Disbiose/veterinária , Feminino , Microbioma Gastrointestinal/fisiologia , Humanos , Doenças Neuroinflamatórias/veterinária , Gravidez , Ratos , Ratos Sprague-Dawley , Privação do Sono/complicações , Privação do Sono/veterinária
15.
Environ Sci Technol ; 56(8): 5247-5255, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35352563

RESUMO

Diatoms, accounting for 40% of the marine primary production and 20% of global carbon dioxide fixation, are threatened by the ongoing ocean warming (OW). However, whether and how these ecologically important phytoplankton adapt to OW remains poorly unknown. Here, we experimentally examined the metabolic adaptation of a globally important diatom species Skeletonema dohrnii (S. dohrnii) to OW at two elevated temperatures (24 and 28 °C compared with 20 °C) under short-term (∼300 generations) and long-term (∼700 generations) selection. Both warming levels significantly increased the cell growth rate but decreased the chlorophyll a content. The contents of particulate organic carbon (POC) and particulate organic nitrogen (PON) decreased significantly initially (i.e., until 300 generations) at two temperature treatments but completely recovered after 700 generations of selection, suggesting that S. dohrnii ultimately developed thermal adaptation. Proteomic analysis demonstrated that elevated temperatures upregulated energy metabolism via glycolysis, tricarboxylic acid cycle, and fatty acid oxidation as well as nitrogen acquisition and utilization, which in turn reduced substance storage because of trade-off in the 300th generation, thus decreasing POC and PON. Interestingly, populations at both elevated temperatures exhibited significant proteome plasticity in the 700th generation, as primarily demonstrated by the increased lipid catabolism and glucose accumulation, accounting for the recovery of POC and PON. Changes occurring in cells at the 300th and 700th generations demonstrate that S. dohrnii can adapt to the projected OW, and readjusting the energy metabolism is an important adaptive strategy.


Assuntos
Diatomáceas , Clorofila A/metabolismo , Nitrogênio/metabolismo , Proteômica , Temperatura
16.
Rev Sci Instrum ; 92(8): 083201, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470413

RESUMO

We design and develop a high-performance magnetic shielding system for a long baseline fountain-type atom interferometer. The shielding system is achieved by a combination of passive shielding using permalloy and active compensation with coils. An 11.4 m-long three-layer cylindrical shield is completed by the process of welding, local annealing, and entire annealing. The active compensations compress the residual magnetic field to 8.0 nT max-to-min and the corresponding gradient below 30 nT/m over 10 m along the axial direction in which external compensation, internal compensation, and constant magnetic field (C-field) compensation reduce the inhomogeneities to 25.0, 12.6, and 1.7 nT (standard deviation) sequentially. We estimate that this system could reduce the systematic error of the quadratic Zeeman shift to the 10-13 level for the weak equivalence principle test with a simultaneous 85Rb-87Rb dual-species atom interferometer.

17.
Blood ; 135(25): 2302-2315, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32384137

RESUMO

Erythropoiesis is a complex multistage process that involves differentiation of early erythroid progenitors to enucleated mature red blood cells, in which lineage-specific transcription factors play essential roles. Erythroid Krüppel-like factor (EKLF/KLF1) is a pleiotropic erythroid transcription factor that is required for the proper maturation of the erythroid cells, whose expression and activation are tightly controlled in a temporal and differentiation stage-specific manner. Here, we uncover a novel role of G-protein pathway suppressor 2 (GPS2), a subunit of the nuclear receptor corepressor/silencing mediator of retinoic acid and thyroid hormone receptor corepressor complex, in erythrocyte differentiation. Our study demonstrates that knockdown of GPS2 significantly suppresses erythroid differentiation of human CD34+ cells cultured in vitro and xenotransplanted in nonobese diabetic/severe combined immunodeficiency/interleukin-2 receptor γ-chain null mice. Moreover, global deletion of GPS2 in mice causes impaired erythropoiesis in the fetal liver and leads to severe anemia. Flow cytometric analysis and Wright-Giemsa staining show a defective differentiation at late stages of erythropoiesis in Gps2-/- embryos. Mechanistically, GPS2 interacts with EKLF and prevents proteasome-mediated degradation of EKLF, thereby increasing EKLF stability and transcriptional activity. Moreover, we identify the amino acids 191-230 region in EKLF protein, responsible for GPS2 binding, that is highly conserved in mammals and essential for EKLF protein stability. Collectively, our study uncovers a previously unknown role of GPS2 as a posttranslational regulator that enhances the stability of EKLF protein and thereby promotes erythroid differentiation.


Assuntos
Eritropoese/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Fatores de Transcrição Kruppel-Like/fisiologia , Sequência de Aminoácidos , Animais , Células Cultivadas , Sequência Conservada , Células Precursoras Eritroides/citologia , Técnicas de Silenciamento de Genes , Transplante de Células-Tronco Hematopoéticas , Humanos , Subunidade gama Comum de Receptores de Interleucina/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/química , Fígado/embriologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Mapeamento de Interação de Proteínas , Processamento de Proteína Pós-Traducional , Estabilidade Proteica , Proteólise , Interferência de RNA , RNA Interferente Pequeno/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Transplante Heterólogo , Ubiquitinação , Regulação para Cima
18.
Sci Total Environ ; 698: 134289, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514034

RESUMO

Microeukaryotes are the key ecosystem drivers mediating marine productivity, the food web and biogeochemical cycles. The northwestern Pacific Ocean (NWPO), as one of the world's largest oligotrophic regions, remains largely unexplored regarding diversity and biogeography of microeukaryotes. Here, we investigated the community composition and geographical distribution of microeukaryotes collected from the euphotic zone of three different regions in the NWPO using high-throughput sequencing of the 18S rRNA gene and quantified the contributions of environmental factors on the distributions of microeukaryotes. The relative abundance of different group taxa, except for Ciliophora, presented distinct patterns in each region, and Metazoa and Dinoflagellata dominated the community, contributing approximately half of reads abundance. Spatial and environmental factors explained 66.01% of community variation in the NWPO. Temperature was the most important environmental factor significantly correlated with community structure. Bacterial biomass was also significantly correlated with microeukaryotic distribution, especially for Dinoflagellata and Diatomea. Network analysis showed strong correlations between microeukaryotic groups and free-living bacteria and different bacterial taxa were correlated with specific microeukaryotic groups, indicating that their interactions enabled microeukaryotic groups to adapt to diverse environments. This study provides a first glance at the diversity and geographical distribution of microeukaryotes in the NWPO and sheds light on the biotic and abiotic factors in shaping the microeukaryotic community in the ocean.


Assuntos
Biodiversidade , Monitoramento Ambiental , Cilióforos , Diatomáceas , Dinoflagellida , Ecossistema , Eutrofização , Oceano Pacífico , Água do Mar
19.
Math Biosci Eng ; 16(5): 3345-3367, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-31499617

RESUMO

The convolutional neural networks (CNN) applied in remote sensing scene classification have two common problems. One is that these models have large number of parameters, which causes over-fitting easily. The other is that the network is not deep enough, thus more abstract semantic information cannot be extracted. To solve these two problems, we propose a simple and efficient full convolutional network based on DenseNet for remote sensing scene classification. We construct a small number of convolutional kernels to generate a large number of reusable feature maps by dense connections, which makes the network deeper, but does not increase the number of parameters significantly. Our network is so deep that it has more than 100 layers. However, it has only about 7 million parameters, which is far less than the number of VGG's parameters. Then we incorporate an adaptive average 3D pooling operation in our network. This operation fixes feature maps of size 7 × 7 from the last DenseBlock to 1 × 1 and decreases the number of channels from 1024 to 512, thus the whole network can accept input images with different sizes. Furthermore, we design the convolutional layer instead of the fully connected layer that is used as a classifier usually, so that the output features of the network can be classified without flattening operation, which simplifies the classification operation. Finally, a good model is trained by exploiting pre-trained weights and data augmentation technology. Compared with several state-of-the-art algorithms, our algorithm improves classification performance significantly on UCM dataset, AID dataset, OPTIMAL-31 dataset and NWPU-RESISC45 dataset.

20.
Appl Environ Microbiol ; 85(19)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31375486

RESUMO

Phytoplankton blooms are natural phenomena in the ocean, which are the results of rapid cell growth of some phytoplankton species in a unique environment. However, little is known about the molecular events occurring during the bloom. Here, we compared metaproteomes of two phytoplankton Heterosigma akashiwo and Prorocentrum donghaiense in the coastal East China Sea. H. akashiwo and P. donghaiense accounted for 7.82% and 4.74% of the phytoplankton community protein abundances in the nonbloom sample, whereas they contributed to 60.13% and 78.09%, respectively, in their individual blooming samples. Compared with P. donghaiense, H. akashiwo possessed a significantly higher abundance of light-harvesting complex proteins, carbonic anhydrasem and RuBisCO. The blooming H. akashiwo cells expressed more proteins related to external nutrient acquisition, such as bicarbonate transporter SLC4, ammonium transporter, nitrite transporter, and alkaline phosphatase, while the blooming P. donghaiense cells highly expressed proteins related to extra- and intracellular organic nutrient utilization, such as amino acid transporter, 5'-nucleotidase, acid phosphatase, and tripeptidyl-peptidase. The strong capabilities of light harvesting, as well as acquisition and assimilation of inorganic carbon, nitrogen, and phosphorus, facilitated the formation of the H. akashiwo bloom under the high turbidity and inorganic nutrient-sufficient condition, whereas the competitive advantages in organic nutrient acquisition and reallocation guaranteed the occurrence of the P. donghaiense bloom under the inorganic nutrient-insufficient condition. This study highlights the power of metaproteomics for revealing the underlying molecular behaviors of different coexisting phytoplankton species and advances our knowledge on the formation of phytoplankton blooms.IMPORTANCE A deep understanding of the mechanisms driving bloom formation is a prerequisite for effective bloom management. Metaproteomics was applied in this study to reveal the adaptive and responsive strategies of two coexisting phytoplankton species, H. akashiwo and P. donghaiense, during their bloom periods. Metabolic features and niche divergence in light harvesting, as well as carbon, nitrogen, and phosphorus acquisition and assimilation likely promoted the bloom occurrence under different environments. The molecular behaviors of coexisting bloom-causing species will give clues for bloom monitoring and management in the oceans.


Assuntos
Fitoplâncton/genética , Fitoplâncton/metabolismo , Proteoma/metabolismo , Carbono/metabolismo , China , Proliferação Nociva de Algas , Nitrogênio/metabolismo , Oceano Pacífico , Fósforo/metabolismo
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