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1.
Nat Immunol ; 21(8): 927-937, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32632289

RESUMO

In response to pathogenic threats, naive T cells rapidly transition from a quiescent to an activated state, yet the underlying mechanisms are incompletely understood. Using a pulsed SILAC approach, we investigated the dynamics of mRNA translation kinetics and protein turnover in human naive and activated T cells. Our datasets uncovered that transcription factors maintaining T cell quiescence had constitutively high turnover, which facilitated their depletion following activation. Furthermore, naive T cells maintained a surprisingly large number of idling ribosomes as well as 242 repressed mRNA species and a reservoir of glycolytic enzymes. These components were rapidly engaged following stimulation, promoting an immediate translational and glycolytic switch to ramp up the T cell activation program. Our data elucidate new insights into how T cells maintain a prepared state to mount a rapid immune response, and provide a resource of protein turnover, absolute translation kinetics and protein synthesis rates in T cells ( https://www.immunomics.ch ).


Assuntos
Ativação Linfocitária/fisiologia , Biossíntese de Proteínas/imunologia , Linfócitos T/imunologia , Humanos , RNA Mensageiro/imunologia , RNA Mensageiro/metabolismo , Fatores de Transcrição/imunologia , Fatores de Transcrição/metabolismo
2.
Nature ; 592(7855): 639-643, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33790470

RESUMO

Some Plasmodium falciparum repetitive interspersed families of polypeptides (RIFINs)-variant surface antigens that are expressed on infected erythrocytes1-bind to the inhibitory receptor LAIR1, and insertion of DNA that encodes LAIR1 into immunoglobulin genes generates RIFIN-specific antibodies2,3. Here we address the general relevance of this finding by searching for antibodies that incorporate LILRB1, another inhibitory receptor that binds to ß2 microglobulin and RIFINs through their apical domains4,5. By screening plasma from a cohort of donors from Mali, we identified individuals with LILRB1-containing antibodies. B cell clones isolated from three donors showed large DNA insertions in the switch region that encodes non-apical LILRB1 extracellular domain 3 and 4 (D3D4) or D3 alone in the variable-constant (VH-CH1) elbow. Through mass spectrometry and binding assays, we identified a large set of RIFINs that bind to LILRB1 D3. Crystal and cryo-electron microscopy structures of a RIFIN in complex with either LILRB1 D3D4 or a D3D4-containing antibody Fab revealed a mode of RIFIN-LILRB1 D3 interaction that is similar to that of RIFIN-LAIR1. The Fab showed an unconventional triangular architecture with the inserted LILRB1 domains opening up the VH-CH1 elbow without affecting VH-VL or CH1-CL pairing. Collectively, these findings show that RIFINs bind to LILRB1 through D3 and illustrate, with a naturally selected example, the general principle of creating novel antibodies by inserting receptor domains into the VH-CH1 elbow.


Assuntos
Anticorpos/química , Anticorpos/imunologia , Antígenos de Protozoários/química , Antígenos de Protozoários/imunologia , Microscopia Crioeletrônica , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/química , Plasmodium falciparum/química , Plasmodium falciparum/imunologia , Adolescente , Adulto , Sequência de Aminoácidos , Anticorpos/ultraestrutura , Especificidade de Anticorpos , Antígenos de Protozoários/ultraestrutura , Sítios de Ligação de Anticorpos , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Lactente , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/imunologia , Mali , Modelos Moleculares , Plasmodium falciparum/genética , Plasmodium falciparum/ultraestrutura , Domínios Proteicos , Adulto Jovem
3.
Nature ; 598(7882): 662-666, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34616044

RESUMO

The availability of L-arginine in tumours is a key determinant of an efficient anti-tumour T cell response1-4. Consequently, increases of typically low L-arginine concentrations within the tumour may greatly potentiate the anti-tumour responses of immune checkpoint inhibitors, such as programmed death-ligand 1 (PD-L1)-blocking antibodies5. However, currently no means are available to locally increase intratumoural L-arginine levels. Here we used a synthetic biology approach to develop an engineered probiotic Escherichia coli Nissle 1917 strain that colonizes tumours and continuously converts ammonia, a metabolic waste product that accumulates in tumours6, to L-arginine. Colonization of tumours with these bacteria increased intratumoural L-arginine concentrations, increased the number of tumour-infiltrating T cells and had marked synergistic effects with PD-L1 blocking antibodies in the clearance of tumours. The anti-tumour effect of these bacteria was mediated by L-arginine and was dependent on T cells. These results show that engineered microbial therapies enable metabolic modulation of the tumour microenvironment leading to enhanced efficacy of immunotherapies.


Assuntos
Imunoterapia/métodos , Engenharia Metabólica , Microrganismos Geneticamente Modificados , Neoplasias Experimentais/terapia , Transferência Adotiva , Animais , Arginina/metabolismo , Antígeno B7-H1/antagonistas & inibidores , Linhagem Celular Tumoral , Escherichia coli , Feminino , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/microbiologia , Probióticos , Proteoma , Biologia Sintética , Linfócitos T/imunologia , Microambiente Tumoral/imunologia
4.
J Neuroinflammation ; 21(1): 36, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38287311

RESUMO

BACKGROUND: Sepsis-associated encephalopathy (SAE) is an acute cerebral dysfunction caused by sepsis. Neuroinflammation induced by sepsis is considered a potential mechanism of SAE; however, very little is known about the role of the meningeal lymphatic system in SAE. METHODS: Sepsis was established in male C57BL/6J mice by intraperitoneal injection of 5 mg/kg lipopolysaccharide, and the function of meningeal lymphatic drainage was assessed. Adeno-associated virus 1-vascular endothelial growth factor C (AAV1-VEGF-C) was injected into the cisterna magna to induce meningeal lymphangiogenesis. Ligation of deep cervical lymph nodes (dCLNs) was performed to induce pre-existing meningeal lymphatic dysfunction. Cognitive function was evaluated by a fear conditioning test, and inflammatory factors were detected by enzyme-linked immunosorbent assay. RESULTS: The aged mice with SAE showed a significant decrease in the drainage of OVA-647 into the dCLNs and the coverage of the Lyve-1 in the meningeal lymphatic, indicating that sepsis impaired meningeal lymphatic drainage and morphology. The meningeal lymphatic function of aged mice was more vulnerable to sepsis in comparison to young mice. Sepsis also decreased the protein levels of caspase-3 and PSD95, which was accompanied by reductions in the activity of hippocampal neurons. Microglia were significantly activated in the hippocampus of SAE mice, which was accompanied by an increase in neuroinflammation, as indicated by increases in interleukin-1 beta, interleukin-6 and Iba1 expression. Cognitive function was impaired in aged mice with SAE. However, the injection of AAV1-VEGF-C significantly increased coverage in the lymphatic system and tracer dye uptake in dCLNs, suggesting that AAV1-VEGF-C promotes meningeal lymphangiogenesis and drainage. Furthermore, AAV1-VEGF-C reduced microglial activation and neuroinflammation and improved cognitive dysfunction. Improvement of meningeal lymphatics also reduced sepsis-induced expression of disease-associated genes in aged mice. Pre-existing lymphatic dysfunction by ligating bilateral dCLNs aggravated sepsis-induced neuroinflammation and cognitive impairment. CONCLUSION: The meningeal lymphatic drainage is damaged in sepsis, and pre-existing defects in this drainage system exacerbate SAE-induced neuroinflammation and cognitive dysfunction. Promoting meningeal lymphatic drainage improves SAE. Manipulation of meningeal lymphangiogenesis could be a new strategy for the treatment of SAE.


Assuntos
Lesões Encefálicas , Disfunção Cognitiva , Encefalopatia Associada a Sepse , Sepse , Camundongos , Masculino , Animais , Fator C de Crescimento do Endotélio Vascular , Lipopolissacarídeos , Doenças Neuroinflamatórias , Camundongos Endogâmicos C57BL , Sepse/complicações , Lesões Encefálicas/complicações
5.
Vet Res ; 55(1): 80, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886823

RESUMO

Bacteria utilize intercellular communication to orchestrate essential cellular processes, adapt to environmental changes, develop antibiotic tolerance, and enhance virulence. This communication, known as quorum sensing (QS), is mediated by the exchange of small signalling molecules called autoinducers. AI-2 QS, regulated by the metabolic enzyme LuxS (S-ribosylhomocysteine lyase), acts as a universal intercellular communication mechanism across gram-positive and gram-negative bacteria and is crucial for diverse bacterial processes. In this study, we demonstrated that in Streptococcus suis (S. suis), a notable zoonotic pathogen, AI-2 QS enhances galactose utilization, upregulates the Leloir pathway for capsular polysaccharide (CPS) precursor production, and boosts CPS synthesis, leading to increased resistance to macrophage phagocytosis. Additionally, our molecular docking and dynamics simulations suggest that, similar to S. pneumoniae, FruA, a fructose-specific phosphoenolpyruvate phosphotransferase system prevalent in gram-positive pathogens, may also function as an AI-2 membrane surface receptor in S. suis. In conclusion, our study demonstrated the significance of AI-2 in the synthesis of galactose metabolism-dependent CPS in S. suis. Additionally, we conducted a preliminary analysis of the potential role of FruA as a membrane surface receptor for S. suis AI-2.


Assuntos
Galactose , Percepção de Quorum , Streptococcus suis , Streptococcus suis/fisiologia , Galactose/metabolismo , Percepção de Quorum/fisiologia , Virulência , Animais , Cápsulas Bacterianas/metabolismo , Lactonas/metabolismo , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/imunologia , Homosserina/análogos & derivados , Homosserina/metabolismo , Polissacarídeos Bacterianos/metabolismo
6.
Appl Microbiol Biotechnol ; 108(1): 125, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38229330

RESUMO

The gut microbiota is the largest and most complex microecosystem in animals. It is influenced by the host's dietary habits and living environment, and its composition and diversity play irreplaceable roles in animal nutrient metabolism, immunity, and adaptation to the environment. Although the gut microbiota of red deer has been studied, the composition and function of the gut microbiota in Gansu red deer (Cervus elaphus kansuensis), an endemic subspecies of red deer in China, has not been reported. In this study, the composition and diversity of the gut microbiome and fecal metabolomics of C. elaphus kansuensis were identified and compared for the first time by using 16S rDNA sequencing, metagenomic sequencing, and LC-MS/MS. There were significant differences in gut microbiota structure and diversity between wild and farmed C. elaphus kansuensis. The 16S rDNA sequencing results showed that the genus UCRD-005 was dominant in both captive red deer (CRD) and wild red deer (WRD). Metagenomic sequencing showed similar results to those of 16S rDNA sequencing for gut microbiota in CRD and WRD at the phylum and genus levels. 16S rDNA and metagenomics sequencing data suggested that Bacteroides and Bacillus might serve as marker genera for CRD and WRD, respectively. Fecal metabolomics results showed that 520 metabolites with significant differences were detected between CRD and WRD and most differential metabolites were involved in lipid metabolism. The results suggested that large differences in gut microbiota composition and fecal metabolites between CRD and WRD, indicating that different dietary habits and living environments over time have led to the development of stable gut microbiome characteristics for CRD and WRD to meet their respective survival and reproduction needs. KEY POINTS: • Environment and food affected the gut microbiota and fecal metabolites in red deer • Genera Bacteroides and Bacillus may play important roles in CRD and WRD, respectively • Flavonoids and ascorbic acid in fecal metabolites may influence health of red deer.


Assuntos
Bacillus , Cervos , Microbioma Gastrointestinal , Animais , Microbioma Gastrointestinal/genética , Cromatografia Líquida , Espectrometria de Massas em Tandem , Bacillus/genética , DNA Ribossômico/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
7.
BMC Anesthesiol ; 24(1): 205, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858649

RESUMO

BACKGROUND: Laparoscopic partial hepatectomy inevitably decrease patient immune function. Propofol has been shown to have immunomodulatory effects but is associated with hemodynamic side effects. Despite studies showing a negligible impact of remimazolam tosylate on hemodynamics, it has not been reported for partial hepatectomy patients. Its influence on immune function also remains unexplored. This study sought to investigate the differences in immune function and intraoperative hemodynamics between patients who underwent laparoscopic partial hepatectomy with remimazolam tosylate and those who underwent laparoscopic partial hepatectomy with propofol. METHODS: This was a single-center, randomized controlled trial involving 70 patients, who underwent elective laparoscopic partial hepatectomy. The patients were randomly divided into two groups: the remimazolam group (group R) and the propofol group (group P). In this study, the primary outcomes assessed included the patient's immune function and hemodynamic parameters, and the secondary outcomes encompassed the patient's liver function and adverse events. RESULTS: Data from 64 patients (group R, n = 31; group P, n = 33) were analyzed. The differences in the percentages of CD3+, CD4+, CD8+, and NK cells and the CD4+/CD8+ ratio between the two groups were not statistically significant at 1 day or 3 days after surgery. Compared with those in group P, the MAP and HR at T2 and the MAP at T1 in group R were significantly increased(P < 0.05). The differences in HR and MAP at T0, T3, T4, T5, T6, and T7 and HR at T1 between the two groups were not statistically significant. There were no differences in liver function or adverse effects between the two groups, suggesting that remimazolam tosylate is a safe sedative drug(P > 0.05). CONCLUSION: The effects of remimazolam tosylate on the immune function of patients after partial hepatectomy are comparable to those of propofol. Additionally, its minimal effect on hemodynamics significantly decreases the incidence of hypotension during anesthesia induction, thereby enhancing overall perioperative safety. TRIAL REGISTRATION: The trial was registered on May 9, 2022 in the Chinese Clinical Trial Registry, registration number ChiCTR2200059715 (09/05/2022).


Assuntos
Hemodinâmica , Hepatectomia , Laparoscopia , Propofol , Humanos , Masculino , Feminino , Hepatectomia/métodos , Pessoa de Meia-Idade , Hemodinâmica/efeitos dos fármacos , Laparoscopia/métodos , Propofol/administração & dosagem , Propofol/farmacologia , Benzodiazepinas/administração & dosagem , Anestésicos Intravenosos/farmacologia , Anestésicos Intravenosos/administração & dosagem , Adulto , Idoso , Hipnóticos e Sedativos/administração & dosagem
8.
BMC Anesthesiol ; 24(1): 14, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38172686

RESUMO

BACKGROUND: Although video-assisted thoracoscopic surgery (VATS) has advantages of reduced injury and faster healing, patients still endure moderate and severe postoperative pain. Paracetamol and mannitol injection, the first acetaminophen injection in China, has the advantages of convenient administration, rapid onset of action, and no first-pass effect. This aim of this study was to investigate the efficacy of postoperative analgesia with paracetamol and mannitol injection, combined with thoracic paravertebral nerve block (TPVB) in post VATS pain. METHODS: This study was a single-center, prospective, randomized, double-blind controlled clinical trial. Patients scheduled for VATS were randomly divided into three groups, general anesthesia group (Group C), TPVB group (Group T) and TPVB + paracetamol and mannitol injection group (Group TP). In this study, the primary outcome was determined as visual analog scale (VAS) scores at rest and coughing, the secondary observation outcomes were the first time to use analgesic pump, the total consumption of oxycodone in the analgesic pump, number of effective and total analgesic pump compressions at first 48 h postoperatively, the perioperative consumption of sufentanil, time to extubation, hospital length of stay, urine volume, and the incidence of adverse events. RESULTS: In a state of rest and cough, patients in the Group TP showed significantly lower VAS pain scores at 1, 12, 24, and 48 postoperative-hour compared with Group C and Group T. Intraoperative sufentanil and postoperative oxycodone consumption, the first time to press analgesic pump, the times of effective and total compressions of patient- controlled analgesia (PCA) were lower than those of the Group C and Group T. Interestingly, urine output was higher in Group TP. There were no differences between the three groups in terms of extubation time, length of hospital stay and adverse effects, indicating that intravenous paracetamol and mannitol injection is an effective and safe perioperative analgesia method. CONCLUSIONS: Paracetamol and mannitol injection, combined with TPVB may provide important beneficial effects on acute pain control and reduce the consumption of opioid in patients undergoing VATS. TRIAL REGISTRATION: The trial was registered on Jun 19, 2023 in the Chinese Clinical Trial Registry ( https://www.chictr.org.cn/showproj.html?proj=199315 ), registration number ChiCTR2300072623 (19/06/2023).


Assuntos
Acetaminofen , Bloqueio Nervoso , Humanos , Acetaminofen/uso terapêutico , Cirurgia Torácica Vídeoassistida/métodos , Sufentanil , Oxicodona , Estudos Prospectivos , Bloqueio Nervoso/métodos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Analgésicos/uso terapêutico , Analgesia Controlada pelo Paciente/métodos , Tosse , Manitol
9.
Virol J ; 20(1): 164, 2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488599

RESUMO

BACKGROUND: Porcine epidemic diarrhea virus (PEDV) is an α-coronavirus that causes highly contagious intestinal infectious disease, involving clinically characterized by diarrhea, dehydration, vomiting, and high mortality to suckling piglets. As a strategy for antiviral therapy, artificial microRNA (amiRNA) mediated suppression of viral replication has recently become increasingly important. In this study, we evaluated the advantages of using an amiRNA vector against PEDV. METHODS: In this study, we evaluated the advantages of using an amiRNA vector against PEDV. We designed two single amiRNA sequences for different conserved sequences of the PEDV S and N genes, and tested their inhibitory effects on PEDV in Vero cells. RESULTS: It was obvious from the CCK-8 results that the transient transfection of amiRNA was non-toxic to the cells. In addition, our results showed that the transient expression of two amiRNAs (amiRNA-349 and amiRNA-1447) significantly reduced the expression of viral RNA and protein in the cells. The TCID50 results showed that the release of virus particles into the culture supernatant was significantly reduced, with an effect as high as 90%. To avoid virus mutation escape, the above two single amiRNA sequences were tandem in this study (amiRNA-349 + 1447), enabling a single microRNA to be expressed simultaneously. The real-time PCR and Western blot results showed that the inhibitory effect was significantly enhanced in each of the different time periods. The TCID50 results showed that the release of virus particles in the culture supernatant was significantly reduced at the different time periods. CONCLUSIONS: In summary, these results suggest that an RNAi based on amiRNA targeting the conserved region of the virus is an effective method to improve PEDV nucleic acid inhibitors and provide a novel treatment strategy for PEDV infection.


Assuntos
Coronavirus , MicroRNAs , Vírus da Diarreia Epidêmica Suína , Animais , Suínos , Chlorocebus aethiops , Células Vero , Interferência de RNA
10.
BMC Vet Res ; 19(1): 240, 2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980522

RESUMO

BACKGROUND: Leeches are an integral component of aquatic biocenosis and can be found in a wide range of ecosystems such as freshwater, saltwater, flowing, and still-water ecosystems. It especially plays an important role in the freshwater benthic community and is an important part of the food web. In this study, a leech species was found in the mantle cavity of wild freshwater mussels in Zigong City, Sichuan Province, China, and its identity was determined through morphological analysis and molecular biological analysis. RESULTS: The leech is Hemiclepsis khankiana, a new species of Hemiclepsis that has been discovered in Russia in recent years. Through morphological analysis, the current survey observed that the morphological characteristics of Hemiclepsis khankiana eyespots were significantly different from the first reported description. The first pair of eyespots on the leech were separated and clear, while it had been reduced to unclear shadows in the previous report. The phylogenetic tree based on the COI gene showed that the COI gene sequence obtained in this study was in the same evolutionary branch as Hemiclepsis khankiana (MN295420, MN295421). Genetically, it was most closely related to Hemiclepsis kasmiana (mean COI p-distance = 3.98%). CONCLUSIONS: The current study reported on the new distribution range of Hemiclepsis khankiana, which was initially discovered in China. This study indicates that the distribution range of the leech species has expanded, laying a foundation for further studies in China.


Assuntos
Ecossistema , Sanguessugas , Animais , Filogenia , Sanguessugas/genética , Evolução Biológica , China
11.
Int J Mol Sci ; 24(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37298239

RESUMO

Taraxacum kok-saghyz Rodin (TKS) has great potential as an alternative natural-rubber (NR)-producing crop. The germplasm innovation of TKS still faces great challenges due to its self-incompatibility. Carbon-ion beam (CIB) irradiation is a powerful and non-species-specific physical method for mutation creation. Thus far, the CIB has not been utilized in TKS. To better inform future mutation breeding for TKS by the CIB and provide a basis for dose-selection, adventitious buds, which not only can avoid high levels of heterozygosity, but also further improve breeding efficiency, were irradiated here, and the dynamic changes of the growth and physiologic parameters, as well as gene expression pattern were profiled, comprehensively. The results showed that the CIB (5-40 Gy) caused significant biological effects on TKS, exhibiting inhibitory effects on the fresh weight and the number of regenerated buds and roots. Then,15 Gy was chosen for further study after comprehensive consideration. CIB-15 Gy resulted in significant oxidative damages (hydroxyl radical (OH•) generation activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and malondialdehyde (MDA) content) and activated the antioxidant system (superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX)) of TKS. Based on RNA-seq analysis, the number of differentially expressed genes (DEGs) peaked at 2 h after CIB irradiation. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that DNA-replication-/repair- (mainly up-regulated), cell-death- (mainly up-regulated), plant-hormone- (auxin and cytokinin, which are related to plant morphogenesis, were mainly down-regulated), and photosynthesis- (mainly down-regulated) related pathways were involved in the response to the CIB. Furthermore, CIB irradiation can also up-regulate the genes involved in NR metabolism, which provides an alternative strategy to elevate the NR production in TKS in the future. These findings are helpful to understand the radiation response mechanism and further guide the future mutation breeding for TKS by the CIB.


Assuntos
Taraxacum , Transcriptoma , Taraxacum/metabolismo , Melhoramento Vegetal , Perfilação da Expressão Gênica , Borracha/metabolismo , Carbono/metabolismo , Regulação da Expressão Gênica de Plantas
12.
Int J Mol Sci ; 23(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35054839

RESUMO

Genetic variations are an important source of germplasm diversity, as it provides an allele resource that contributes to the development of new traits for plant breeding. Gamma rays have been widely used as a physical agent for mutation creation in plants, and their mutagenic effect has attracted extensive attention. However, few studies are available on the comprehensive mutation profile at both the large-scale phenotype mutation screening and whole-genome mutation scanning. In this study, biological effects on M1 generation, large-scale phenotype screening in M2 generation, as well as whole-genome re-sequencing of seven M3 phenotype-visible lines were carried out to comprehensively evaluate the mutagenic effects of gamma rays on Arabidopsis thaliana. A total of 417 plants with visible mutated phenotypes were isolated from 20,502 M2 plants, and the phenotypic mutation frequency of gamma rays was 2.03% in Arabidopsis thaliana. On average, there were 21.57 single-base substitutions (SBSs) and 11.57 small insertions and deletions (InDels) in each line. Single-base InDels accounts for 66.7% of the small InDels. The genomic mutation frequency was 2.78 × 10-10/bp/Gy. The ratio of transition/transversion was 1.60, and 64.28% of the C > T events exhibited the pyrimidine dinucleotide sequence; 69.14% of the small InDels were located in the sequence with 1 to 4 bp terminal microhomology that was used for DNA end rejoining, while SBSs were less dependent on terminal microhomology. Nine genes, on average, were predicted to suffer from functional alteration in each re-sequenced line. This indicated that a suitable mutation gene density was an advantage of gamma rays when trying to improve elite materials for one certain or a few traits. These results will aid the full understanding of the mutagenic effects and mechanisms of gamma rays and provide a basis for suitable mutagen selection and parameter design, which can further facilitate the development of more controlled mutagenesis methods for plant mutation breeding.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Mutação , Sequenciamento Completo do Genoma/métodos , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Raios gama/efeitos adversos , Genoma de Planta , Taxa de Mutação , Fenótipo , Melhoramento Vegetal
13.
Molecules ; 27(10)2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35630624

RESUMO

Ixeris chinensis (Thunb.) Nakai (IC) is a folk medicinal herb used in Mongolian medical clinics for the treatment of hepatitis and fatty liver diseases even though its pharmacological mechanism has not been well characterized. This study investigated the hepatoprotective mechanism of IC on mice with nonalcoholic fatty liver disease (NAFLD) by integrating gut microbiota and metabolomic analysis. A high-fat diet (HFD) was used to develop nonalcoholic fatty liver disease, after which the mice were treated with oral IC (0.5, 1.5 and 3.0 g/kg) for 10 weeks. HFD induced NAFLD and the therapeutic effects were characterized by pathological and histological evaluations, and the serum indicators were analyzed by ELISA. The gut microbial and metabolite profiles were studied by 16S rRNA sequencing and untargeted metabolomic analysis, respectively. The results showed that the administration of IC resulted in significant decreases in body weight; liver index; serum biomarkers such as ALT, TG, and LDL-C; and the liver inflammatory factors IL-1ß, IL-6, and TNF-α. The 16S rRNA sequencing results showed that administration of IC extract altered both the composition and abundance of the gut microbiota. Untargeted metabolomic analysis of liver samples detected a total of 212 metabolites, of which 128 were differentially expressed between the HFD and IC group. IC was found to significantly alter the levels of metabolites such as L-glutamic acid, pyridoxal, ornithine, L-aspartic acid, D-proline, and N4-acetylaminobutanal, which are involved in the regulation of glutamine and glutamate, Vitamin B6 metabolism, and arginine and proline metabolic pathways. Correlation analysis indicated that the effects of the IC extract on metabolites were associated with alterations in the abundance of Akkermansiaceae, Lachnospiraceae, and Muribaculaceae. Our study revealed that IC has a potential hepatoprotective effect in NAFLD and that its function might be linked to improvements in the composition of gut microbiota and their metabolites.


Assuntos
Asteraceae , Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica/efeitos adversos , Camundongos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Prolina/farmacologia , RNA Ribossômico 16S/genética
14.
J Infect Dis ; 223(12): 2174-2185, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33151309

RESUMO

Citrobacter freundii is a significant cause of human infections, responsible for food poisoning, diarrhea, and urinary tract infections. We previously identified a highly cytotoxic and adhesive C. freundii strain CF74 expressing a type VI secretion system (T6SS). In this study, we showed that in mice-derived macrophages, C. freundii CF74 activated the Nucleotide Oligomerization Domain -Like Receptor Family, Pyrin Domain Containing 3(NLRP3) inflammasomes in a T6SS-dependent manner. The C. freundii T6SS activated the inflammasomes mainly through caspase 1 and mediated pyroptosis of macrophages by releasing the cleaved gasdermin-N domain. The CF74 T6SS was required for flagellin-induced interleukin 1ß release by macrophages. We further show that the T6SS tail component and effector, hemolysin co-regulation protein-2 (Hcp-2), was necessary and sufficient to trigger NLRP3 inflammasome activation. In vivo, the T6SS played a key role in mediating interleukin 1ß secretion and the survival of mice during C. freundii infection in mice. These findings provide novel insights into the role of T6SS in the pathogenesis of C. freundii.


Assuntos
Citrobacter freundii , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Sistemas de Secreção Tipo VI , Animais , Caspase 1 , Citrobacter freundii/patogenicidade , Inflamassomos/imunologia , Interleucina-1beta , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Piroptose
15.
BMC Genomics ; 22(1): 416, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34090338

RESUMO

BACKGROUND: Copper was used for many years in aquaculture operations as an effective algaecide or a parasite treatment of fish. It is an essential nutrient with numerous functions in organisms, but is toxic at high concentrations. However, the toxicity of copper to fish remains unclear. In this study, we used the piebald naked carp, Gymnocypris eckloni, as a model. RNA-seq data from different tissues, including gills, kidney, and liver, were used to investigate the underlying mechanism of copper toxicology in G. eckloni. RESULTS: We compared the transcriptomes from different tissues with different time durations of copper ion treatment. After 72 h copper ion treatment, the number of genes with different expression in gills and liver changed dramatically, but not in kidneys. In KEGG functional enrichment, the pattern of differentially expressed genes (DEGs) was also similar in the gills and liver. The most enriched pathway of DEGs was "Ribosome" in both tissues. Furthermore, we analyzed the expression levels of genes involved in oxidative stress response and protein synthesis using qPCR and RNA-seq data. Our results showed that several genes involved in oxidative stress response were up-regulated both in gills and liver. Up-regulation of these genes indicated that copper treatment caused oxidative stress, which is likely to result in ribosome damage. In addition, our results showed that the expression of Eef1b2, a transcription elongation factor, was decreased in the liver under oxidative stress, and the expression of translation initiation factors Eif4ebp1 and eIF2α, and elongation factor eEF2 was up-regulated. These results supported the idea that oxidative stress inhibits protein synthesis in cells. CONCLUSIONS: Our results indicate that copper exposure caused different responses in different tissues, since the gene expression patterns changed substantially either in the gills or liver, while the effect on the kidney was relatively weak. Furthermore, our results indicated that the expression pattern of the genes involved in the ribosome, which is a complex molecular machine orchestrating protein synthesis in the cell, together with translation initiation factor and elongation factors, were affected by copper exposure both in the gills and liver of piebald naked carp. This result leads us to speculate that the downregulation of global protein synthesis is an acute response strategy of fish to metal-induced oxidative stress. Moreover, we speculate that this strategy not only exists in the selective translation of proteins but also exists in the specific translation of functional proteins in tissues and cells.


Assuntos
Carpas , Animais , Carpas/genética , Cobre/toxicidade , Perfilação da Expressão Gênica , Brânquias , Transcriptoma
16.
J Am Chem Soc ; 143(1): 513-523, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33370103

RESUMO

Catalytic transformation of alcohols via metal-catalyzed cross-coupling reactions is very important, but it typically relies on a multistep procedure. We here report a dynamic kinetic cross-coupling approach for the direct functionalization of alcohols. The feasibility of this strategy is demonstrated by a nickel-catalyzed cross-electrophile arylation reaction of benzyl alcohols with (hetero)aryl electrophiles. The reaction proceeds with a broad substrate scope of both coupling partners. The electron-rich, electron-poor, and ortho-/meta-/para-substituted (hetero)aryl electrophiles (e.g., Ar-OTf, Ar-I, Ar-Br, and inert Ar-Cl) all coupled well. Most of the functionalities, including aldehyde, ketone, amide, ester, nitrile, sulfone, furan, thiophene, benzothiophene, pyridine, quinolone, Ar-SiMe3, Ar-Bpin, and Ar-SnBu3, were tolerated. The dynamic nature of this method enables the direct arylation of benzylic alcohol in the presence of various nucleophilic groups, including nonactivated primary/secondary/tertiary alcohols, phenols, and free indoles. It thus offers a robust alternative to existing methods for the precise construction of diarylmethanes. The synthetic utility of the method was demonstrated by a concise synthesis of biologically active molecules and by its application to peptide modification and conjugation. Preliminary mechanistic studies revealed that the reaction of in situ formed benzyl oxalates with nickel, possibly via a radical process, is an initial step in the reaction with aryl electrophiles.

17.
Arch Insect Biochem Physiol ; 108(1): e21824, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34272758

RESUMO

Insect gonads develop under endocrine signals. In this study, we assessed the characters of partial complementary DNAs encoding the Teleogryllus emma orthologs of 20-hydroxyecdysone (20E)-related genes (RXR, E75, HR3, Hsc70, and Hsp90) and analyzed their expression patterns in both nymph and adult crickets. 20E treatment suppressed expression of TeEcR, TeRXR, TeE75, TeHR3, TeHsc70, and TeHsp90. Temporal expression analysis demonstrated that TeERR and 20E-related genes were expressed in four stages of gonadal development from the fourth-instar nymph stage to the adult stage. The expression pattern of these genes differed in testicular and ovarian development. TeRXR, HR3, TeHsc70, and TeHsp90 were irregularly expressed in gonads of the same developmental stages, while mRNAs encoding TeERR, TeEcR, and TeE75 accumulated in higher levels in ovaries than in testes. RNA interference (RNAi) of TeEcR expression led to decrease of the expression levels of TeEcR, TeRXR, TeHR3, and TeHsc70, while it enhanced TeE75 and TeHsp90 expressions. These results demonstrate that the TeERR and 20E-related genes help regulate gonadal development, while TeEcR appears to inhibit TeE75 expression, TeE75 inhibits HR3 expression. Hsc70 indirectly regulated the expression of the primary and secondary response genes E74A, E75B, and HR3. Hsp90 regulated Usp expression with no direct regulatory relationship with EcR.


Assuntos
Ecdisterona , Gônadas , Gryllidae/metabolismo , Animais , Ecdisterona/genética , Ecdisterona/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genes de Insetos , Gônadas/crescimento & desenvolvimento , Gônadas/metabolismo , Gryllidae/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Masculino , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Testículo/crescimento & desenvolvimento , Testículo/metabolismo
18.
BMC Anesthesiol ; 21(1): 234, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34587905

RESUMO

BACKGROUND: Postoperative nausea and vomiting (PONV) as a clinically most common postoperative complication requires multimodal antiemetic medications targeting at a wide range of neurotransmitter pathways. Lacking of neurobiological mechanism makes this 'big little problem' still unresolved. We aim to investigate whether gut-vagus-brain reflex generally considered as one of four typical emetic neuronal pathways might be the primary mediator of PONV. METHODS: Three thousand two hundred twenty-three patients who underwent vagus nerve trunk resection (esophagectomy and gastrectomy) and non-vagotomy surgery (hepatectomy, pulmonary lobectomy and colorectomy) from December 2016 to January 2019 were enrolled. Thirty cases of gastrectomy with selective resection on the gastric branch of vagus nerve were also recruited. Nausea and intensity of vomiting was recorded within 24 h after the operation. RESULTS: PONV occurred in 11.9% of 1187 patients who underwent vagus nerve trunk resection and 28.7% of 2036 non-vagotomy patients respectively. Propensity score matching showed that vagotomy surgeries accounted for 19.9% of the whole PONV incidence, much less than that observed in the non-PONV group (35.1%, P <  0.01). Multivariate logistic regression result revealed that vagotomy was one of underlying factor that significantly involved in PONV (OR = 0.302, 95% CI, 0.237-0.386). Nausea was reported in 5.9% ~ 8.6% vagotomy and 12 ~ 17% non-vagotomy patients. Most vomiting were mild, being approximately 3% in vagotomy and 8 ~ 13% in non-vagotomy patients, while sever vomiting was much less experienced. Furthermore, lower PONV occurrence (10%) was also observed in gastrectomy undergoing selective vagotomy. CONCLUSION: Patients undergoing surgeries with vagotomy developed less PONV, suggesting that vagus nerve dependent gut-brain signaling might mainly contribute to PONV.


Assuntos
Analgesia/métodos , Eixo Encéfalo-Intestino/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Náusea e Vômito Pós-Operatórios/epidemiologia , Nervo Vago/efeitos dos fármacos , Nervo Vago/cirurgia , Encéfalo/fisiopatologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/efeitos dos fármacos , Reflexo/efeitos dos fármacos
19.
Bull Environ Contam Toxicol ; 106(5): 792-798, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33759007

RESUMO

Zinc pollution impairs neural processes and protein function and also effects calcium-related transcriptional regulation and enzyme activity. In this study, we investigated pathways that potentially respond to calcium signaling under Zn2+ stress. Specifically we measured relative expressions of GeCNAα, GeCNB, GeMT, GeTNF-α, GeIL-1ß, and GeHsp90 in gills, livers, and kidneys of the indicator species Gymnocypris eckloni and found wide variation in their expression between tissues during the course of Zn2+ exposure. Notably, GeCNAα, GeCNB, GeTNF-α, GeIL-1ß, and GeMT were rapidly and strongly up-regulated in gills; GeIL-1ß and GeHsp90 transcription was quickly induced in kidneys; and GeCNB, GeTNF-α, GeIL-1ß, and GeHsp90 were most rapidly up-regulated in livers. GeCNAα and GeMT showed a contrasting late transcriptional up-regulation. These results suggest independent branches for chelation and immune responses during self-protection against Zn2+ toxicity, and the immune response appears to be faster than metal chelation.


Assuntos
Carpas , Cyprinidae , Animais , Calcineurina , Brânquias , Zinco/toxicidade
20.
BMC Vet Res ; 16(1): 456, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228649

RESUMO

BACKGROUND: Goose parvoviruses (GPVs) spread globally and cause a huge economic loss to the poultry industry. Although the attenuated GPV vaccines play a key role in preventing the disease caused by GPV, the molecular basis for the attenuation of GPV is barely known. RESULTS: A highly attenuated GPV strain, GPV-CZM-142, was generated through blindly passaging of the highly pathogenic strain, GPV-CZM, in goose embryonic fibroblasts (GEF) for 142 generations. The GEF-adapted GPV strain's virulence was 10,000 times weaker than its wild type counterpart, GPV-CZM, based on the ELD50 (50% Embryo Lethal Dose). By comparing with the wild type strain, genome sequencing analysis identified adapted mutations either in ITR or in NS and VP1 of GPV-CZM-142. CONCLUSIONS: The highly attenuated GPV strain, GPV-CZM-142, provides a GPV vaccine candidate, and the identified virulence-related mutations give a novel insight into the molecular determinants of GPV virulence.


Assuntos
Infecções por Parvoviridae/veterinária , Parvovirinae/crescimento & desenvolvimento , Parvovirinae/genética , Doenças das Aves Domésticas/virologia , Animais , Células Cultivadas , Fibroblastos , Gansos , Infecções por Parvoviridae/embriologia , Infecções por Parvoviridae/virologia , Parvovirinae/imunologia , Doenças das Aves Domésticas/embriologia , Doenças das Aves Domésticas/imunologia , Análise de Sequência de DNA , Vacinas Atenuadas , Vacinas Virais , Virulência
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