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1.
Proc Natl Acad Sci U S A ; 120(5): e2207091120, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36689650

RESUMO

Galectin-4, a member of the galectin family of animal glycan-binding proteins (GBPs), is specifically expressed in gastrointestinal epithelial cells and is known to be able to bind microbes. However, its function in host-gut microbe interactions remains unknown. Here, we show that intracellular galectin-4 in intestinal epithelial cells (IECs) coats cytosolic Salmonella enterica serovar Worthington and induces the formation of bacterial chains and aggregates. Galectin-4 enchains bacteria during their growth by binding to the O-antigen of lipopolysaccharides. Furthermore, the binding of galectin-4 to bacterial surfaces restricts intracellular bacterial motility. Galectin-4 enhances caspase-1 activation and mature IL-18 production in infected IECs especially when autophagy is inhibited. Finally, orally administered S. enterica serovar Worthington, which is recognized by human galectin-4 but not mouse galectin-4, translocated from the intestines to mesenteric lymph nodes less effectively in human galectin-4-transgenic mice than in littermate controls. Our results suggest that galectin-4 plays an important role in host-gut microbe interactions and prevents the dissemination of pathogens. The results of the study revealed a novel mechanism of host-microbe interactions that involves the direct binding of cytosolic lectins to glycans on intracellular microbes.


Assuntos
Galectina 4 , Inflamassomos , Animais , Camundongos , Humanos , Inflamassomos/metabolismo , Galectina 4/metabolismo , Células Epiteliais/metabolismo , Bactérias , Antígenos O/metabolismo
2.
Inorg Chem ; 63(24): 11361-11368, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38815165

RESUMO

Herein, we report the synthesis of a flexible bis-cyclopentadienyl ligand L (the doubly deprotonated form of H2L (1,3-bis(2,4-di-tert-butylcyclopentadienyldimethylsilyl)benzene)), demonstrating its ability to stabilize a series of di-iron hydrido complexes. Notably, this ligand facilitates the isolation of an unprecedented anionic cyclopentadienyl ligand-supported di-iron trihydride complex, LFe2(µ-H)3Li(THF) (2), functioning as a synthon for the [Fe2(µ-H)3]- core and providing access to heterobimetallic complexes 4-6 with coinage metals.

3.
Genomics ; 115(4): 110648, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37217086

RESUMO

Programmed death-ligand 1 (PD-L1) has been widely used in immunotherapy evaluation of patients with non-small cell lung cancer (NSCLC). However, the effect is not particularly ideal, and the association between PD-L1 and genetic alterations requires more exploration. Here, we performed targeted next-generation sequencing and PD-L1 immunohistochemistry (IHC) testing for PD-L1 expression on both tumor cells (TCs) and tumor-infiltrating immune cells (ICs) in 1549 patients. Our studies showed that surgical method of resection was positively correlated with IC+, and a low tumor mutation burden (TMB) was negatively correlated with TC+. Furthermore, we found that EGFR was mutually exclusive with both ALK and STK11. In addition, the features between PD-L1 expression status and genomic alterations were characterized. These results suggest that clinical characteristics and molecular phenotypes are associated with PD-L1 expression signatures, which may provide novel insights for improving the efficiency of immune checkpoint inhibitors (ICIs) in immunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamento farmacológico , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Mutação , Imunoterapia/métodos
4.
Circulation ; 146(25): 1950-1967, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36420731

RESUMO

BACKGROUND: Cardiac regeneration after injury is limited by the low proliferative capacity of adult mammalian cardiomyocytes (CMs). However, certain animals readily regenerate lost myocardium through a process involving dedifferentiation, which unlocks their proliferative capacities. METHODS: We bred mice with inducible, CM-specific expression of the Yamanaka factors, enabling adult CM reprogramming and dedifferentiation in vivo. RESULTS: Two days after induction, adult CMs presented a dedifferentiated phenotype and increased proliferation in vivo. Microarray analysis revealed that upregulation of ketogenesis was central to this process. Adeno-associated virus-driven HMGCS2 overexpression induced ketogenesis in adult CMs and recapitulated CM dedifferentiation and proliferation observed during partial reprogramming. This same phenomenon was found to occur after myocardial infarction, specifically in the border zone tissue, and HMGCS2 knockout mice showed impaired cardiac function and response to injury. Finally, we showed that exogenous HMGCS2 rescues cardiac function after ischemic injury. CONCLUSIONS: Our data demonstrate the importance of HMGCS2-induced ketogenesis as a means to regulate metabolic response to CM injury, thus allowing cell dedifferentiation and proliferation as a regenerative response.


Assuntos
Infarto do Miocárdio , Miócitos Cardíacos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Coração , Miocárdio/metabolismo , Camundongos Knockout , Regeneração/genética , Proliferação de Células , Mamíferos
5.
J Am Chem Soc ; 145(39): 21378-21386, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37733877

RESUMO

Stimuli-responsive molecular crystals have attracted considerable attention as promising smart materials with applications in various fields such as sensing, actuation, and optoelectronics. Understanding the structure-mechanical property relationships, however, remains largely unexplored when it comes to functionalizing these organic crystals. Here, we report three polymorphic crystals (Forms A, B, and C) formed by the non-threaded complexation of a dibenzo[18]crown-6 (DB18C6) ether ring and an azobenzene-based ammonium cation, each exhibiting distinct thermal phase transitions, photoinduced deformations, and mechanical behavior. Structural changes on going from Form A to Form B and from Form C to Form B during heating and cooling, respectively, are observed by single-crystal X-ray crystallography. Form A shows photoinduced reversible bending, whereas Form B exhibits isotropic expansion. Form C displays uniaxial negative expansion with a remarkable increase of 44% in thickness under photoirradiation. Force measurements and nanoindentation reveal that the soft crystals of Form A with a low elastic modulus demonstrate a significant photoresponse, attributed to the non-threaded molecular structure, which permits flexibility of the azobenzene unit. This work represents a significant advance in the understanding of the correlation between structure-thermomechanical and structure-photomechanical properties necessary for the development of multi-stimulus-responsive materials with tailored properties.

6.
J Org Chem ; 88(19): 13528-13534, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37681712

RESUMO

Enantioselective synthesis of nabscessin C (1), an aminocyclitol amide with antimicrobial activity, is reported. Starting from myo-inositol, (+)-nabscessin C was synthesized in 12 isolation steps. Desymmetrization of 2-deoxygenated 4,6-dibenzylinositol was achieved using lipase from porcine pancreas (PPL), and the stereochemistry was established by X-ray crystallography. This method has the potential for synthesizing other cyclitol-derived compounds.


Assuntos
Ciclitóis , Animais , Suínos , Ciclitóis/química , Estereoisomerismo , Lipase , Inositol
7.
Genome Res ; 29(10): 1622-1634, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31537639

RESUMO

How individual genes are regulated from a mitochondrial polycistronic transcript to have variable expression remains an enigma. Here, through bisulfite sequencing and strand-specific mapping, we show mitochondrial genomes in humans and other animals are strongly biased to light (L)-strand non-CpG methylation with conserved peak loci preferentially located at gene-gene boundaries, which was also independently validated by MeDIP and FspEI digestion. Such mtDNA methylation patterns are conserved across different species and developmental stages but display dynamic local or global changes during development and aging. Knockout of DNMT3A alone perturbed mtDNA regional methylation patterns, but not global levels, and altered mitochondrial gene expression, copy number, and oxygen respiration. Overexpression of DNMT3A strongly increased mtDNA methylation and strand bias. Overall, methylation at gene bodies and boundaries was negatively associated with mitochondrial transcript abundance and also polycistronic transcript processing. Furthermore, HPLC-MS confirmed the methylation signals on mitochondria DNA. Together, these data provide high-resolution mtDNA methylation maps that revealed a strand-specific non-CpG methylation, its dynamic regulation, and its impact on the polycistronic mitochondrial transcript processing.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/genética , DNA Mitocondrial/genética , Epigenoma/genética , Animais , Ilhas de CpG/genética , DNA Metiltransferase 3A , Regulação da Expressão Gênica/genética , Humanos , Mitocôndrias/genética
8.
Nitric Oxide ; 120: 9-15, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34995767

RESUMO

Hydrogen sulfide (H2S) as an endogenous gaseous signaling molecule had been proved to play a vital role in gametes physiology, covering meiosis, maturation and aging. However, little is known about H2S involvement in embryonic development. The present study explored the positive effect of H2S on human early embryonic development. Results validated that the two H2S producing enzymes, CBS and CSE mRNA and proteins were identified in donated human cleavage and blastocyst-stage embryos. The l-cysteine incubation produced endogenous H2S in human blastocysts. NaHS positively affected in vitro blastulation. Single-cell RNA-seq analysis identified 228 differentially expressed genes (DEGs) after NaHS treatment versus the control. The Gene Ontology (GO) enrichment analysis of DEGs showed that genes for protein modification and metabolism were significantly enriched in the NaHS treatment group. For the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, 2-oxocarboxylic acid metabolism, glycosaminoglycan biosynthesis-keratan sulfate, steroid biosynthesis, carbon metabolism, and biosynthesis of amino acids were significantly enriched. Six DEGs, including Neural EGFL like 1 (NELL1), aconitase 1 (ACO1), phosphoglycerate mutase 1 (PGAM1), TP53 induced glycolysis regulatory phosphatase (TIGAR), UDP-GlcNAc:betaGal beta-1,3-N-acetylglucosaminyltransferase 2 (B3GNT2), and carbohydrate Sulfotransferase 4 (CHST4) were validate by real-time RT-PCR. These findings suggest that H2S is a positive regulator of early embryonic development and may alter the transcription of embryonic genes for protein modification and metabolism in human embryos.


Assuntos
Blastocisto/fisiologia , Desenvolvimento Embrionário/fisiologia , Expressão Gênica/fisiologia , Sulfeto de Hidrogênio/metabolismo , Blastocisto/efeitos dos fármacos , Cistationina beta-Sintase/genética , Cistationina beta-Sintase/metabolismo , Cistationina gama-Liase/genética , Cistationina gama-Liase/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Humanos , RNA Mensageiro/metabolismo , Sulfetos/farmacologia , Transcriptoma/efeitos dos fármacos
9.
Inorg Chem ; 61(3): 1327-1334, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34994560

RESUMO

Titanium phosphorus oxides (TiPOs) are promising energy-conversion materials, but most are of tetravalent titanium (TiIV), with the trivalent TiIIIPOs less explored because of instability and obstacles in synthesis. In this study, we used a simple synthetic strategy and prepared three new TiIIIPOs with different phosphorus oxoanions: the phosphate Ca2Ti(HPO4)2(PO4)·H2O (1), the phosphite CaTi2(H2O)(HPO3)4·H2O (2), and the hypophosphite Ti(H2PO2)3 (3). Each possesses different structures in one, two, and three dimensions, yet they are related to one another because of their infinite chains. Compound 1 exhibits proton-coupled electron transfer (PCET) reactivity in a solid state, losing one proton from its own HPO4 in oxidation to yield Ca2Ti(HPO4)(PO4)2·H2O (designated as 1O), while compound 2 also exhibits PCET reactivity in which the octahedral core [TiIII(H2O)]3+ gives off two protons to become a titanyl unit [TiIV═O]2+ under oxidation, yielding CaTi2O(HPO3)4·H2O (2O). Both 1O and 2O retain their original frameworks from before oxidation, but there are some changes in the hydrogen and Ti-O bonds that affect the IR absorption and powder X-ray diffraction patterns. Compound 3 represents the first titanium hypophosphite, and two polymorphs were discovered that show structures related to 1 and 2. This work demonstrates a simple strategy that is effective for preparing titanium(III) compounds in a pure phase; further, new findings in the pathways of solid-state PCET reactions promote a greater understanding of the self-sustaining oxidation behavior for TiIIIPO solid materials.

10.
Environ Sci Technol ; 56(23): 17197-17205, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36342784

RESUMO

Fixed capital stock functions as an embodied energy storage system that connects economic activities which do not happen simultaneously. This paper constructs a dynamic energy input-output model to analyze embodied energy flows and stocks along both temporal and spatial dimensions from 2000 to 2014. The results show that 2043 exajoule of embodied energy was stored in the global fixed capital stock in 2014, which was about three times the world's direct energy use. Compared with those in developed countries, the gaps between the dynamic energy footprints and the traditional ones were larger in fast-developing countries. Net embodied energy usually flowed from high-intensity economies to lower-intensity economies, and around 10% of the energy embodied in trade came from depreciation. The dynamic embodied energy indicators provide information for improving energy efficiency and mitigating corresponding problems from the perspective of consumption.


Assuntos
Comércio , Fontes Geradoras de Energia , China , Fenômenos Físicos
11.
Mol Biol Rep ; 49(6): 4929-4941, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35025029

RESUMO

N6-methyladenosine (m6A), the methylation targeting the N6 position of adenosine, is the most common internal modification of mRNA in eukaryotes. Considering the roles of m6A in regulating gene expression, the investigation of m6A roles in the biological processes including cell renewal, differentiation, apoptosis, and invasion of cancer cells has become a hot research topic. There are three kinds of protein involved in m6A regulation. The methyltransferases and demethylases cooperatively regulate the m6A levels, while the m6A reading proteins recognize the m6A sites and mediate multiple m6A-dependent biological functions including mRNA splicing, transfer, translation, and degradation. At present, a large number of studies have found that the changes of m6A levels in tumor cells play a very important role in the occurrence and development of tumors, as well as metastasis and invasion of tumor cells. This review summarizes the different roles of m6A modification in the occurrence and development of various cancers, and discusses the possibility of choosing the m6A related proteins as potential therapeutic targets.


Assuntos
Adenosina , Neoplasias , Adenosina/análogos & derivados , Adenosina/metabolismo , Humanos , Metilação , Neoplasias/metabolismo , RNA Mensageiro/genética
12.
Proc Natl Acad Sci U S A ; 116(9): 3518-3523, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808745

RESUMO

The globo-series glycosphingolipids (GSLs) SSEA3, SSEA4, and Globo-H specifically expressed on cancer cells are found to correlate with tumor progression and metastasis, but the functional roles of these GSLs and the key enzyme ß1,3-galactosyltransferase V (ß3GalT5) that converts Gb4 to SSEA3 remain largely unclear. Here we show that the expression of ß3GalT5 significantly correlates with tumor progression and poor survival in patients, and the globo-series GSLs in breast cancer cells form a complex in membrane lipid raft with caveolin-1 (CAV1) and focal adhesion kinase (FAK) which then interact with AKT and receptor-interacting protein kinase (RIP), respectively. Knockdown of ß3GalT5 disrupts the complex and induces apoptosis through dissociation of RIP from the complex to interact with the Fas death domain (FADD) and trigger the Fas-dependent pathway. This finding provides a link between SSEA3/SSEA4/Globo-H and the FAK/CAV1/AKT/RIP complex in tumor progression and apoptosis and suggests a direction for the treatment of breast cancer, as demonstrated by the combined use of antibodies against Globo-H and SSEA4.


Assuntos
Neoplasias da Mama/genética , Galactosiltransferases/genética , Glicoesfingolipídeos/genética , Microdomínios da Membrana/genética , Antígenos Glicosídicos Associados a Tumores/genética , Antígenos Glicosídicos Associados a Tumores/metabolismo , Apoptose/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caveolina 1/genética , Caveolina 1/metabolismo , Progressão da Doença , Proteína de Domínio de Morte Associada a Fas/genética , Feminino , Proteína-Tirosina Quinases de Adesão Focal/genética , Regulação Neoplásica da Expressão Gênica/genética , Glicoesfingolipídeos/metabolismo , Humanos , Substâncias Macromoleculares/química , Substâncias Macromoleculares/metabolismo , Microdomínios da Membrana/metabolismo , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-akt/genética , Saporinas/genética , Transdução de Sinais/genética , Antígenos Embrionários Estágio-Específicos/genética , Antígenos Embrionários Estágio-Específicos/metabolismo
13.
J Obstet Gynaecol Res ; 48(7): 1816-1828, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35373468

RESUMO

AIM: The purpose of the study was to establish a mathematical model to help rank the order of blastocysts and assist selection of which blastocysts to warm in vitrified-thawed embryo transfer cycles. DESIGN: A total of 2862 women who underwent first vitrified-thawed single blastocyst transfer (SBT) between July 2015 and July 2019 were retrospectively recruited and randomized into a training set (n = 2289) and testing set (n = 573). Least absolute shrinkage and selection operator (LASSO) regression was used to screen the factors critical to live birth (LB). Subsequently, a nomogram model was established to convert the effect of each factor on LB into a measurable score. The efficacy of the model was then evaluated by the receiver operating characteristic and calibration curve. The performance of the model was also internally tested in the testing set. RESULTS: Maternal age, endometrial thickness, oocyte number, day-3 embryo quality, blastocyst morphology, and blastulation day were selected as the critical predictors of LB in the vitrified-thawed SBT cycle and fitted into a nomogram model. The area under the curve (AUC) of the model was 0.67, and the AUC in the testing set was 0.64, which indicates moderate discrimination. The calibration curve showed good concordance between prediction and observation. Importantly, the score of each variable in the nomogram helped to rank the order of the blastocysts resulting in LB. CONCLUSIONS: The nomogram model can provide guidance for embryo selection in vitrified-thawed blastocyst transfer cycles, which may help to optimize the LB rate.


Assuntos
Transferência Embrionária , Nomogramas , Blastocisto , Criopreservação , Transferência Embrionária/métodos , Feminino , Humanos , Nascido Vivo , Gravidez , Taxa de Gravidez , Distribuição Aleatória , Estudos Retrospectivos , Vitrificação
14.
Socioecon Plann Sci ; 80: 101029, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35283541

RESUMO

In recent years, public health emergencies have occurred frequently, posing a serious threat to the regional economy and the safety of people's lives and property. In particular, the outbreak of the COVID-19 novel coronavirus this year has caused serious losses to the global economy. On this basis, this article attempts to use modern advanced artificial intelligence technology and modern social science and technology to provide technical assistance and support for the prevention and control of major public health incidents, in order to improve the Chinese government's public relations capabilities and response to public health emergencies. Ability and level. This article attempts to use 3S technology closely related to artificial intelligence technology to design and establish a public health emergency response system, so as to improve the government's response and decision-making ability to respond to and deal with public health emergencies, and reduce the occurrence of emergencies. The results showed that among the 298 respondents, 145 believed that public health emergencies depend on human-to-human transmission. Most event information is acceptable, while 169 people who rely on mobile phones for information think that most of them are acceptable, and 89 people who rely on TV media for information think that most of them are acceptable. It shows that the use of artificial intelligence technology can effectively solve and prevent the further development of the situation, and at the same time improve the government's ability and level to respond to major public health emergencies, and increase the government's prestige in the eyes of the public.

15.
Plant Mol Biol ; 105(6): 585-599, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33651261

RESUMO

KEY MESSAGE: Total of 14 SNPs associated with overwintering-related traits and 75 selective regions were detected. Important candidate genes were identified and a possible network of cold-stress responses in woody plants was proposed. Local adaptation to low temperature is essential for woody plants to against changeable climate and safely survive the winter. To uncover the specific molecular mechanism of low temperature adaptation in woody plants, we sequenced 134 core individuals selected from 494 paper mulberry (Broussonetia papyrifera), which naturally distributed in different climate zones and latitudes. The population structure analysis, PCA analysis and neighbor-joining tree analysis indicated that the individuals were classified into three clusters, which showed forceful geographic distribution patterns because of the adaptation to local climate. Using two overwintering phenotypic data collected at high latitudes of 40°N and one bioclimatic variable, genome-phenotype and genome-environment associations, and genome-wide scans were performed. We detected 75 selective regions which possibly undergone temperature selection and identified 14 trait-associated SNPs that corresponded to 16 candidate genes (including LRR-RLK, PP2A, BCS1, etc.). Meanwhile, low temperature adaptation was also supported by other three trait-associated SNPs which exhibiting significant differences in overwintering traits between alleles within three geographic groups. To sum up, a possible network of cold signal perception and responses in woody plants were proposed, including important genes that have been confirmed in previous studies while others could be key potential candidates of woody plants. Overall, our results highlighted the specific and complex molecular mechanism of low temperature adaptation and overwintering of woody plants.


Assuntos
Adaptação Fisiológica/genética , Temperatura Baixa , Fenômenos Fisiológicos Vegetais , Plantas/genética , Alelos , Sequência de Bases , Clima , Estudo de Associação Genômica Ampla , Morus/genética , Morus/fisiologia , Fenótipo , Polimorfismo de Nucleotídeo Único , Temperatura
16.
J Sci Food Agric ; 101(15): 6452-6462, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33997981

RESUMO

BACKGROUND: The separation and purification of Porphyra haitanensis polysaccharide (PHP), and the determination of changes in molecular weight (Mw) and antioxidant capacity after in vitro digestion, were undertaken. RESULTS: Analysis of two polysaccharide fractions (PHP0.5-1-UF and PHP1.0-1-UF) by various techniques showed that they were very pure sulfated polysaccharides without pigment or protein. PHP0.5-1-UF was filamentous or 'tape-like' sheets, whereas PHP1.0-1-UF had some filaments and large numbers of rounded aggregates. The Mw of PHP, PHP0.5-1-UF and PHP1.0-1-UF was 2.06 × 106 (±2.02%), 6.68 × 106 (±3.17%), and 1.14 × 106 (±3.44%) (g mol-1 ), respectively. After in vitro digestion, the Mw of PHP, PHP0.5-1-UF, and PHP1.0-1-UF decreased. Their antioxidant capacities were markedly higher than before digestion, especially PHP0.5-1-UF and its digestion products, which might be related to the reductions in Mw. CONCLUSION: These findings provide a greater understanding of the separation and purification of sulfated polysaccharides and the influence of digestion on biological activity. They also contribute to the practical application of sulfated polysaccharides in functional foods. © 2021 Society of Chemical Industry.


Assuntos
Antioxidantes/química , Extratos Vegetais/isolamento & purificação , Polissacarídeos/isolamento & purificação , Porphyra/química , Antioxidantes/isolamento & purificação , Peso Molecular , Extratos Vegetais/química , Polissacarídeos/química , Análise Espectral , Sulfatos/química , Difração de Raios X
17.
Circulation ; 139(5): 647-659, 2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30586712

RESUMO

BACKGROUND: The impact of gut microbiota on the regulation of host physiology has recently garnered considerable attention, particularly in key areas such as the immune system and metabolism. These areas are also crucial for the pathophysiology of and repair after myocardial infarction (MI). However, the role of the gut microbiota in the context of MI remains to be fully elucidated. METHODS: To investigate the effects of gut microbiota on cardiac repair after MI, C57BL/6J mice were treated with antibiotics 7 days before MI to deplete mouse gut microbiota. Flow cytometry was applied to examine the changes in immune cell composition in the heart. 16S rDNA sequencing was conducted as a readout for changes in gut microbial composition. Short-chain fatty acid (SCFA) species altered after antibiotic treatment were identified by high-performance liquid chromatography. Fecal reconstitution, transplantation of monocytes, or dietary SCFA or Lactobacillus probiotic supplementation was conducted to evaluate the cardioprotective effects of microbiota on the mice after MI. RESULTS: Antibiotic-treated mice displayed drastic, dose-dependent mortality after MI. We observed an association between the gut microbiota depletion and significant reductions in the proportion of myeloid cells and SCFAs, more specifically acetate, butyrate, and propionate. Infiltration of CX3CR1+ monocytes to the peri-infarct zone after MI was also reduced, suggesting impairment of repair after MI. Accordingly, the physiological status and survival of mice were significantly improved after fecal reconstitution, transplantation of monocytes, or dietary SCFA supplementation. MI was associated with a reorganization of the gut microbial community such as a reduction in Lactobacillus. Supplementing antibiotic-treated mice with a Lactobacillus probiotic before MI restored myeloid cell proportions, yielded cardioprotective effects, and shifted the balance of SCFAs toward propionate. CONCLUSIONS: Gut microbiota-derived SCFAs play an important role in maintaining host immune composition and repair capacity after MI. This suggests that manipulation of these elements may provide opportunities to modulate pathological outcome after MI and indeed human health and disease as a whole.


Assuntos
Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Monócitos/imunologia , Infarto do Miocárdio/microbiologia , Miocárdio/imunologia , Animais , Bactérias/imunologia , Bactérias/metabolismo , Modelos Animais de Doenças , Disbiose , Ácidos Graxos/administração & dosagem , Ácidos Graxos/metabolismo , Transplante de Microbiota Fecal , Feminino , Interações Hospedeiro-Patógeno , Lactobacillus/imunologia , Lactobacillus/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/metabolismo , Monócitos/transplante , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Probióticos/administração & dosagem , Células RAW 264.7
18.
Plant Biotechnol J ; 18(2): 373-388, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31276273

RESUMO

Orchardgrass (Dactylis glomerata L.) is an important forage grass for cultivating livestock worldwide. Here, we report an ~1.84-Gb chromosome-scale diploid genome assembly of orchardgrass, with a contig N50 of 0.93 Mb, a scaffold N50 of 6.08 Mb and a super-scaffold N50 of 252.52 Mb, which is the first chromosome-scale assembled genome of a cool-season forage grass. The genome includes 40 088 protein-coding genes, and 69% of the assembled sequences are transposable elements, with long terminal repeats (LTRs) being the most abundant. The LTRretrotransposons may have been activated and expanded in the grass genome in response to environmental changes during the Pleistocene between 0 and 1 million years ago. Phylogenetic analysis reveals that orchardgrass diverged after rice but before three Triticeae species, and evolutionarily conserved chromosomes were detected by analysing ancient chromosome rearrangements in these grass species. We also resequenced the whole genome of 76 orchardgrass accessions and found that germplasm from Northern Europe and East Asia clustered together, likely due to the exchange of plants along the 'Silk Road' or other ancient trade routes connecting the East and West. Last, a combined transcriptome, quantitative genetic and bulk segregant analysis provided insights into the genetic network regulating flowering time in orchardgrass and revealed four main candidate genes controlling this trait. This chromosome-scale genome and the online database of orchardgrass developed here will facilitate the discovery of genes controlling agronomically important traits, stimulate genetic improvement of and functional genetic research on orchardgrass and provide comparative genetic resources for other forage grasses.


Assuntos
Dactylis , Evolução Molecular , Flores , Redes Reguladoras de Genes , Dactylis/genética , Flores/genética , Repetições de Microssatélites , Fenótipo , Filogenia
19.
Ann Rheum Dis ; 79(6): 811-818, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32269059

RESUMO

OBJECTIVES: Obesity is a well-recognised risk factor for osteoarthritis (OA). Our aim is to characterise body mass index (BMI)-associated pathological changes in the osteochondral unit and determine if obesity is the major causal antecedent of early joint replacement in patients with OA. METHODS: We analysed the correlation between BMI and the age at which patients undergo total knee replacement (TKR) in 41 023 patients from the Australian Orthopaedic Association National Joint Replacement Registry. We then investigated the effect of BMI on pathological changes of the tibia plateau of knee joint in a representative subset of the registry. RESULTS: 57.58% of patients in Australia who had TKR were obese. Patients with overweight, obese class I & II or obese class III received a TKR 1.89, 4.48 and 8.08 years earlier than patients with normal weight, respectively. Microscopic examination revealed that horizontal fissuring at the osteochondral interface was the major pathological feature of obesity-related OA. The frequency of horizontal fissure was strongly associated with increased BMI in the predominant compartment. An increase in one unit of BMI (1 kg/m2) increased the odds of horizontal fissures by 14.7%. 84.4% of the horizontal fissures were attributable to obesity. Reduced cartilage degradation and alteration of subchondral bone microstructure were also associated with increased BMI. CONCLUSIONS: The key pathological feature in OA patients with obesity is horizontal fissuring at the osteochondral unit interface. Obesity is strongly associated with a younger age of first TKR, which may be a result of horizontal fissures.


Assuntos
Cartilagem Articular/patologia , Obesidade/complicações , Osteoartrite do Joelho/etiologia , Osteoartrite do Joelho/patologia , Tíbia/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho , Índice de Massa Corporal , Epífises/patologia , Feminino , Humanos , Peso Corporal Ideal , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia
20.
Appl Environ Microbiol ; 86(18)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32651209

RESUMO

The genetic basis of plant local adaptation has been extensively studied, yet the interplay between local adaptation, plant genetic divergence, and the microbial community remains unclear. Our study used the restriction-site associated DNA sequencing (RAD-seq) approach to explore genetic divergence in Broussonetia papyrifera and used internal transcribed spacers (ITS) to characterize fungal community. RAD-seq results show that B. papyrifera individuals could be divided into three genotypes; this genotyping result was consistent with the classification of climate type at the sample site. Most of the 101 highly differentiated genes were related to stress resistance and the microbiome. Moreover, ß-diversity results indicated that genetic divergence had a significant effect on fungal community across all compartments (P < 0.01). At genus and operational taxonomic unit (OTU) level, Mortierella, Hannaella oryzae, OTU81578 (Mortierella), and OTU1665209 (H. oryzae) were found to be the major OTUs that contribute to differences in fungal community. The properties of cooccurrence networks vary greatly among three genotypes. The results of redundancy analysis (RDA) indicated that B. papyrifera-associated fungal community was significantly related to its local adaptability. Our findings suggest that genetic divergence of B. papyrifera is closely related to local adaptation, with significant effects on the associated fungal community, which in turn would enhance host local adaptability. This improves present understanding about the coevolution of microbial communities and the host plant.IMPORTANCE The coevolution of plants with the associated fungal community and its effect on plant adaptability are not clear, especially for native trees. This study focuses on the genetic basis of local adaptation in plants and the effect of genetic divergence of Broussonetia papyrifera on the associated fungal community. We identified genes related to the microbiome that are important for local adaptation of the host. Our results show that genetic divergence in B. papyrifera significantly affects the fungal community, which has a close connection with local adaptation. This helps us to understand the relationship between local adaptation, genetic divergence, and associated fungal communities. This study highlights the effect of plant genetic divergence on associated fungal community for native trees and establishes a close connection between this effect and local adaptability in the host. In addition, these observations lay a foundation for the research of coevolution of plants and their symbiotic microbiome through genome-wide association study (GWAS).


Assuntos
Broussonetia/genética , Broussonetia/microbiologia , Fungos/isolamento & purificação , Variação Genética , Micobioma , Adaptação Fisiológica , Simbiose
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