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The enhanced utilization of biomass-derived chemicals for the generation of high value aromatics through an advanced catalytic strategy has captured considerable attention within the realm of eco-friendly manufacturing. This work presented four innovative three-dimensional rod-shaped mesoporous Ce-based MOF materials, which were coupled with a H-donor solvent to facilitate vanillin hydrodeoxygenation and macromolecular lignin. Under the optimized conditions (30 mg CoCe@C catalyst, 2 MPa N2 pressure, 15 mL isopropanol, 190 °C, and 5 h), the CoCe@C catalyst achieved nearly complete conversion of vanillin and demonstrated 87.8 % selectivity in the hydrogen-donor solvent. The characterization findings suggested that the synergy between metallic Co and oxygen vacancy sites enabled the effective activation of CHO group in vanillin, leading to formation of reactive product MMP. In addition, the optimal CoCe@C catalyst could also achieve macromolecular lignin hydrodeoxygenation to obtain high yield of lignin oil products with narrower molecular weight distribution. This study presented a viable approach for the concurrent utilization of lignin derivatives in the generation of high value fuels and chemicals.
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Lignina , Estruturas Metalorgânicas , Oxigênio , Fenóis , Lignina/química , Catálise , Oxigênio/química , Estruturas Metalorgânicas/química , Fenóis/química , Cobalto/química , Benzaldeídos/químicaRESUMO
The development of high-temperature nondestructive testing (NDT) requires ultrasonic transducers with good temperature resistance and high sensitivity for improved detection efficiency. Piezoelectric composite can improve the performance of transducers because of its high electromechanical coupling coefficient and adjustable acoustic impedance. In this study, 1-3-2 composites and 1-3-2 high-temperature composite ultrasonic transducers (HTCUTs) based on 0.36BiScO3-0.64PbTiO3 (BSPT), which is preferred piezoelectric materials at 200 ° C- 300 ° C, and high-temperature epoxy with a center frequency of 6 MHz were designed and fabricated. From 25 ° C to 250 ° C, 1-3-2 composites show a higher electromechanical coupling coefficient kt especially at high temperatures (~0.53 at 25 ° C and ~0.64 at 250 ° C) than monolithic BSPT (~0.5). The signal of the pulse-echo response of 1-3-2 HTCUTs is distinguishable up to 250 ° C and remains stable ( [Formula: see text] mV) below 150 ° C, exhibiting higher sensitivity (improved by 7 dB) than that of monolithic BSPT high-temperature ultrasonic transducers (HTUTs). Bandwidth has been greatly enhanced especially at high temperatures (~103% at 250 ° C) compared with that of monolithic BSPT HTUTs (~30% at 250 ° C). To verify the excellent performance, B-mode scanning imaging measurement of a stepped steel block and defect location detection of a steel block was performed, showing the potential for high-temperature NDT applications.
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Modulation of cell death is a powerful strategy employed by pathogenic bacteria to evade host immune clearance and occupy profitable replication niches during infection. Intracellular pathogens employ the type III secretion system (T3SS) to deliver effectors, which interfere with regulated cell death pathways to evade immune defenses. Here, we reveal that poly(ADP-ribose) polymerase-1 (PARP1)-dependent cell death restrains Edwardsiella piscicida's proliferation in mouse monocyte macrophages J774A.1, of which PARP1 activation results in the accumulation of poly(ADP-ribose) (PAR) and enhanced inflammatory response. Moreover, E. piscicida, an important intracellular pathogen, leverages a T3SS effector YfiD to impair PARP1's activity and inhibit PAR accumulation. Once translocated into the host nucleus, YfiD binds to the ADP-ribosyl transferase (ART) domain of PARP1 to suppress its PARylation ability as the pharmacological inhibitor of PARP1 behaves. Furthermore, the interaction between YfiD and ART mainly relies on the complete unfolding of the helical domain, which releases the inhibitory effect on ART. In addition, YfiD impairs the inflammatory response and cell death in macrophages and promotes in vivo colonization and virulence of E. piscicida. Collectively, our results establish the functional mechanism of YfiD as a potential PARP1 inhibitor and provide more insights into host defense against bacterial infection.
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Edwardsiella , Infecções por Enterobacteriaceae , Animais , Camundongos , Sistemas de Secreção Tipo III/metabolismo , Poli Adenosina Difosfato Ribose , Virulência , Edwardsiella/metabolismoRESUMO
The purpose of this study was to evaluate the preventive role and underlying mechanisms of fucoxanthin (Fx) on dextran sulfate sodium (DSS)-induced colitis in mice. The present data demonstrated that oral administration of Fx (50 and 200 mg/kg body weight/day) for 36 days significantly alleviated the severity of colitis in DSS-treated mice, as evidenced by attenuating body weight loss, bloody stool, diarrhea, shortened colon length, colonic epithelium distortion, a thin mucus layer, goblet cell depletion, damaged crypts, and extensive infiltration of inflammatory cells in the colonic mucosa. Additionally, Fx notably relieved DSS-induced intestinal epithelial barrier dysfunction via maintaining the tight junction function and preventing excessive apoptosis of colonic epithelial cells. Moreover, Fx effectively diminished colonic inflammation and oxidative stress in DSS-treated mice, and its mechanisms might be due to blunting the activation of NF-κB and NLRP3 inflammasome signaling pathways. Furthermore, Fx also modulates DSS-induced gut microbiota dysbiosis via recovering the richness and diversity of gut microbiota and reshaping the structure of gut microbiota, such as increasing the Firmicutes and Bacteroidota (F/B) ratio and elevating the relative abundance of some potential beneficial bacteria, including Lactobacillaceae and Lachnospiraceae. Overall, Fx might be developed as a promising functional ingredient to prevent colitis and maintain intestinal homeostasis.
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Colite , Microbioma Gastrointestinal , Xantofilas , Camundongos , Animais , Sulfato de Dextrana/efeitos adversos , Disbiose/induzido quimicamente , Disbiose/tratamento farmacológico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Colo/metabolismo , Camundongos Endogâmicos C57BL , Modelos Animais de DoençasRESUMO
Optical imaging and phototherapy in deep tissues face notable challenges due to light scattering. We use encoded acoustic holograms to generate three-dimensional acoustic fields within the target medium, enabling instantaneous and robust modulation of the volumetric refractive index, thereby noninvasively controlling the trajectory of light. Through this approach, we achieved a remarkable 24.3% increase in tissue heating rate in vitro photothermal effect tests on porcine skin. In vivo photoacoustic imaging of mouse brain vasculature exhibits an improved signal-to-noise ratio through the intact scalp and skull. These findings demonstrate that our strategy can effectively suppress light scattering in complex biological tissues by inducing low-angle scattering, achieving an effective depth reaching the millimeter scale. The versatility of this strategy extends its potential applications to neuroscience, lithography, and additive manufacturing.
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Técnicas Fotoacústicas , Camundongos , Animais , Suínos , Técnicas Fotoacústicas/métodos , Fototerapia , Crânio , Acústica , RefratometriaRESUMO
H-NS, the histone-like nucleoid-structuring protein in bacteria, regulates the stability of the bacterial genome by inhibiting the transcription of horizontally transferred genes, such as the type III and type VI secretion systems (T3/T6SS). While eukaryotic histone posttranslational modifications (PTMs) have been extensively studied, little is known about prokaryotic H-NS PTMs. Here, we report that the acetylation of H-NS attenuates its ability to silence horizontally transferred genes in response to amino acid nutrition and immune metabolites. Moreover, LC-MS/MS profiling showed that the acetyllysine sites of H-NS and K120 are indispensable for its DNA-binding ability. Acetylation of K120 leads to a low binding affinity for DNA and enhances T3/T6SS expression. Furthermore, acetylation of K120 impairs the AT-rich DNA recognition ability of H-NS. In addition, lysine acetylation in H-NS modulates in vivo bacterial virulence. These findings reveal the mechanism underlying H-NS PTMs and propose a novel mechanism by which bacteria counteract the xenogeneic silencing of H-NS.
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Proteínas de Bactérias , Proteínas de Ligação a DNA , Processamento de Proteína Pós-Traducional , Acetilação , Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cromatografia Líquida , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Regulação Bacteriana da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Lisina/metabolismo , Espectrometria de Massas em TandemRESUMO
BACKGROUND: Sex hormones play important roles in the estrus return of post-weaning sows. Previous studies have demonstrated a complex and bi-directional regulation between sex hormones and gut microbiota. However, the extent to which the gut microbiota affects estrus return of post-weaning sows is largely unknown. RESULTS: In this study, we first screened 207 fecal samples from well-phenotyped sows by 16S rRNA gene sequencing and identified significant associations between microbes and estrus return of post-weaning sows. Using metagenomic sequencing data from 85 fecal samples, we identified 37 bacterial species that were significantly associated with estrus return. Normally returning sows were characterized by increased abundances of L. reuteri and P. copri and decreased abundances of B. fragilis, S. suis, and B. pseudolongum. The changes in gut microbial composition significantly altered the functional capacity of steroid hormone biosynthesis in the gut microbiome. The results were confirmed in a validation cohort. Significant changes in sex steroid hormones and related compounds were found between normal and non-return sows via metabolome analysis. An integrated analysis of differential bacterial species, metagenome, and fecal metabolome provided evidence that normal return-associated bacterial species L. reuteri and Prevotella spp. participated in the degradation of pregnenolone, progesterone, and testosterone, thereby promoting estrogen biosynthesis. Furthermore, the microbial metabolites related to sow energy and nutrient supply or metabolic disorders also showed relationships with sow estrus return. CONCLUSIONS: An integrated analysis of differentially abundant bacterial species, metagenome, and fecal metabolome revealed the involvement of L. reuteri and Prevotella spp. in sow estrus return. These findings provide deep insight into the role of gut microbiota in the estrus return of post-weaning sows and the complex cross-talk between gut microbiota and sex hormones, suggesting that the manipulation of the gut microbiota could be an effective strategy to improve sow estrus return after weaning.
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SCOPE: Skeletal muscle atrophy is a critical feature of cancer-associated cachexia (CAC) and it is responsible for poor quality of life and high mortality in cancer patients. The previous study demonstrates that eicosapentaenoic acid-enriched phospholipids (EPA-PL) prevent body weight loss in a mouse model of CAC. However, the role of EPA-PL on cancer-induced skeletal muscle atrophy remains unclear. METHODS AND RESULTS: In the present study, a Lewis lung carcinoma (LLC) mouse model is established, then the effect and underlying mechanism of EPA-PL on skeletal muscle atrophy in LLC-bearing mice are investigated. The results reveal that EPA-PL treatment significantly attenuates skeletal muscle atrophy in LLC-bearing mice, as evidenced by suppressing the reductions of skeletal muscle mass, myofiber cross-sectional area, and grip strength. Besides, the study finds that EPA-PL alleviated cancer-induced skeletal muscle atrophy via balancing muscle protein degradation and synthesis, inhibiting type I oxidative muscle fibers atrophy, and promoting mitochondrial function. Furthermore, the results also indicate that EPA-PL may counteract skeletal muscle atrophy in LLC mouse model via a sirtuin 1-dependent mechanism. CONCLUSION: These findings provide evidence that EPA-PL may be beneficial as a nutritional supplement for prevention and treatment of cancer-induced skeletal muscle atrophy.
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Carcinoma Pulmonar de Lewis , Camundongos , Animais , Carcinoma Pulmonar de Lewis/complicações , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/metabolismo , Ácido Eicosapentaenoico/farmacologia , Ácido Eicosapentaenoico/metabolismo , Fosfolipídeos/metabolismo , Qualidade de Vida , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/etiologia , Atrofia Muscular/prevenção & controle , Caquexia/tratamento farmacológico , Caquexia/etiologia , Caquexia/prevenção & controle , Modelos Animais de Doenças , Músculo Esquelético/metabolismoRESUMO
The viable but nonculturable (VBNC) state is a dormant state of nonsporulating bacteria that enhances survival in adverse environments. Systematic genome-wide research on the genetic basis of VBNC formation is warranted. In this study, we demonstrated that the marine bacterium Vibrio alginolyticus lost culturability but remained viable and entered into the VBNC state when exposed to low nutrient concentrations for prolonged periods of time. Using transposon-insertion sequencing (Tn-seq), we identified 635 determinants governing the formation of the VBNC state, including 322 genes with defective effects on VBNC formation and 313 genes contributing to entry into the VBNC state. Tn-seq analysis revealed that genes involved in various metabolic pathways were shown to have an inhibitory effect on VBNC formation, while genes related to chemotaxis or folate biosynthesis promoted entry into the VBNC state. Moreover, the effects of these genes on the formation of VBNC were validated with the growth of deletion mutants of eight selected genes under nutrient-limited conditions. Interestingly, fleQ and pyrI were identified as essential for entry into the VBNC state, and they affected the formation of the VBNC state independent of RpoE or ToxR regulation. Collectively, these results provide new insights into the mechanism of VBNC formation. KEY POINTS: ⢠Vibrio alginolyticus has the ability to enter into the VBNC state under low nutrient conditions at low temperature. ⢠The 635 determinants for entry into the VBNC state were systematically identified by transposon-insertion sequencing. ⢠PyrI and FleQ were validated to play significant roles in the formation of the VBNC state.
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Temperatura Baixa , Vibrio alginolyticus , Viabilidade MicrobianaRESUMO
The urban development in the Yellow River basin (YRB) varies widely. Therefore, it is necessary to choose a development path that fits the characteristics of each city to achieve high-quality development. The purpose of this paper is to address the problem of how to choose a characteristic path for high-quality development and clarify its suitability for YRB cities. Firstly, based on data from 50 YRB cities from 2011 to 2020, the suitability evaluation was carried out from the perspective of an ecological niche, followed by the measurement of sub-dimensional niche breadth and overlap. The results confirmed the great diversity of development between cities and the intense competition for resources. Then, based on the classification approach using the k-means method, this study proposes a method for selecting a suitable path for high-quality development. It classifies the suitable paths into 3 major types with 7 minor types and recommends policies for the suitable paths for YRB cities. The systematic thinking and specific path selection method for the high-quality development of YRB cities is not only of practical significance for implementing city classification strategies but also provides a reference for the sustainable development of basin cities in other countries.
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Ecossistema , Rios , Humanos , Cidades , Políticas , Convulsões , ChinaRESUMO
In this work, a bilayer nanocoating was constructed on the surface of flexible polyurethane (FPU) foam with Ti3C2 MXene and polyethyleneimine-modified silica nanoparticles (mSiO2-NP@PEI) through layer-by-layer self-assembly technology, successfully obtaining modified flexible polyurethane composites (MFPU) with excellent flame retardancy, photothermal conversion and solar water desalination properties. The structure and morphology of MFPU foams were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Transmission electron microscope (TEM) and Scanning electron microscope (SEM). The MFPU with three coating cycles (MFPU3) had the best flame retardancy and smoke suppression performances, mainly in terms of decreased peak heat release rate (pHRR), peak smoke production rate (pSPR) and total smoke production (TSP) by 71.3 %, 62.1 % and 74.5 %, respectively, compared to those of neat FPU. In addition, MFPU foams exhibited extraordinary light-to-heat conversion and solar water desalination capabilities. MFPU3 could reach 120 °C in 138 s and its steam conversion efficiency η was as high as 89.6 %, which was 116.0 % higher than that of unmodified foam and had a 262.8 % increase over pure water. The flame retardant MFPU foams with excellent photothermal conversion efficiency will exhibit great application potential in solar water desalination and power generation.
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Skeletal muscle fiber characteristics (MFCs) have been extensively studied due to their importance to human health and athletic ability, as well as to the quantity and quality of livestock meat production. Hence, we performed a genome-wide association study (GWAS) on nine muscle fiber traits by using whole genome sequence data in an eight-breed crossed heterogeneous stock pig population. This GWAS revealed 67 quantitative trait loci (QTLs) for these traits. The most significant GWAS signal was detected in the region of Sus scrofa chromosome 12 (SSC12) containing the MYH gene family. Notably, we identified a significant SNP rs322008693 (P = 7.52E-09) as the most likely causal mutation for the total number of muscle fibers (TNMF) QTL on SSC1. The results of EMSA and luciferase assays indicated that the rs322008693 SNP resided in a functional element. These findings provide valuable molecular markers for pig meat production selection as well as for deciphering the genetic mechanisms of the muscle fiber physiology.
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Estudo de Associação Genômica Ampla , Fibras Musculares Esqueléticas , Humanos , Animais , Suínos/genética , Locos de Características Quantitativas , Carne/análise , Fenótipo , Polimorfismo de Nucleotídeo Único , Sus scrofa/genéticaRESUMO
Intestinal barrier dysfunction has emerged as a potential contributor to the development of several severe diseases. Herein, the effect and underlying mechanism of DHA-enriched phospholipids (DHA-PL) and EPA-enriched phospholipids (EPA-PL) on protecting against lipopolysaccharide (LPS)-induced intestinal barrier injury were elucidated. C57BL/6J male mice were fed an AIN-93G diet containing 1% DHA-PL or EPA-PL for 4 weeks and then were intraperitoneally injected with LPS (10 mg/kg) to cause intestinal barrier injury. The results manifested that DHA-PL and EPA-PL pretreatment balanced apoptosis and autophagy in intestinal epithelial cells and maintained intestinal tight junction integrity. Our findings also demonstrated that cotreatment with EX-527, a sirtuin 1 specific inhibitor, hindered the role of DHA-PL and EPA-PL against LPS-evoked intestinal barrier injury through reversing the inhibitory action of them on NF-κB and MAPKs activation as well as their potentiating actions on Nrf2 nuclear translocation. Overall, DHA-PL and EPA-PL alleviated LPS-mediated intestinal barrier injury via inactivation of the NF-κB and MAPKs pathways as well as activating the Nrf2 antioxidant pathway via up-regulating sirtuin 1.
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Ácido Eicosapentaenoico , Lipopolissacarídeos , Animais , Ácidos Docosa-Hexaenoicos/farmacologia , Lipopolissacarídeos/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosfolipídeos , Sirtuína 1/genética , Sirtuína 1/metabolismoRESUMO
Maternal gut microbiota is an important regulator for the metabolism and immunity of the fetus during pregnancy. Recent studies have indicated that maternal intestinal microbiota is closely linked to the development of fetus and infant health. Some bacterial metabolites are considered to be directly involved in immunoregulation of fetus during pregnancy. However, the detailed mechanisms are largely unknown. In this study, we exploited the potential correlation between the gut microbiota of pregnant sows and the occurrence of stillborn piglets by combining the 16S rRNA gene and metagenomic sequencing data, and fecal metabolome in different cohorts. The results showed that several bacterial species from Bacteroides, potential pathogens, and LPS-producing bacteria exhibited significantly higher abundances in the gut of sows giving birth to stillborn piglets. Especially, Bacteroides fragilis stood out as the key driver in both tested cohorts and showed the most significant association with the occurrence of stillborn piglets in the DN1 cohort. However, several species producing short-chain fatty acids (SCFAs), such as Prevotella copri, Clostridium butyricum and Faecalibacterium prausnitzii were enriched in the gut of normal sows. Functional capacity analysis of gut microbiome revealed that the pathways associated with infectious diseases and immune diseases were enriched in sows giving birth to stillborn piglets. However, energy metabolism had higher abundance in normal sows. Fecal metabolome profiling analysis found that Lysophosphatidylethanolamine and phosphatidylethanolamine which are the main components of cell membrane of Gram-negative bacteria showed significantly higher concentration in stillbirth sows, while SCFAs had higher concentration in normal sows. These metabolites were significantly associated with the stillborn-associated bacterial species including Bacteroides fragilis. Lipopolysaccharide (LPS), IL-1ß, IL-6, FABP2, and zonulin had higher concentration in the serum of stillbirth sows, indicating increased intestinal permeability and pro-inflammatory response. The results from this study suggested that certain sow gut bacterial species in late trimester of pregnancy, e.g., an excess abundance of Bacteroides fragilis, produced high concentration of LPS which induced sow pro-inflammatory response and might cause the death of the relatively weak piglets in a farrow. This study provided novel evidences about the effect of maternal gut microbiota on the fetus development and health.
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Microbioma Gastrointestinal , Natimorto , Humanos , Animais , Suínos , Gravidez , Feminino , RNA Ribossômico 16S , Lipopolissacarídeos , Bactérias , InflamaçãoRESUMO
Under adverse circumstances, bacteria enter the viable but non-culturable (VBNC) state, a dormancy-like state for survival. The altered gene regulation underlying the entry of the VBNC state has not yet been well elucidated. Here, we reported that a subpopulation of cells (23.8 %) in Vibrio alginolyticus cultures enters the VBNC state in response to nutrient limitation at alkaline pH. The proteolysis of pivotal virulence regulator ToxR at these conditions is associated with VBNC formation. Meantime, ToxR abrogation impaired the mobility and the expression of virulence-associated genes, resulting in attenuated virulence in V. alginolyticus. RNA-seq and ChIP-seq analyses of the cells grown in VBNC-inducing conditions revealed that ToxR directly controls the expression of â¼8 genes including ahpC and dps involved in reactive oxygen species (ROS) resistance. ToxR binds to the promoter regions of kdgR, ppiC, ahpC, and dps and further controls their respective expression under oxidative stress conditions. The cells with impaired ToxR accumulated detrimental intracellular ROS. Moreover, these genes contribute to bacterial culturability as their in-frame deletion strains exhibiting severely decreased plate counts and the complementary strain showed rescued viability. Collectively, this study revealed the role of ToxR in switching on the VBNC state by sensing unfavorable environmental signals such as endogenous ROS (hydrogen peroxide, H2O2) in V. alginolyticus and provided mechanistic insights into Vibrio lifestyle adaptation in the marine environment.
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Vibrio alginolyticus , Virulência , Adaptação Fisiológica/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Peróxido de Hidrogênio , Proteólise , Espécies Reativas de Oxigênio/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Vibrio alginolyticus/efeitos dos fármacos , Vibrio alginolyticus/genética , Vibrio alginolyticus/patogenicidade , Virulência/genéticaRESUMO
BACKGROUND: Members of the Erysipelotrichaceae family have a high abundance in the intestinal tract of mammals, and have been reported to be associated with host metabolic disorders and inflammatory diseases. In our previous study, we found that the abundance of Erysipelotrichaceae strains in the cecum was associated with the concentration of N-acetylgalactosamine (GalNAc). However, only a few members of Erysipelotrichaceae have been isolated and cultured, and their main characteristics, genomic information and the functional capacity of carbohydrate metabolism remain unknown. RESULTS: In this study, we tested 10 different kinds of commercially available media and successfully isolated five Erysipelotrichaceae strains from healthy porcine feces. The five isolates were Gram-positive, and their colonies on Gifu anaerobic medium (GAM) or modified GAM were approximately 0.25-1.0 mm in diameter, and they were circular, white, convex, moist, translucent, and contained colony margins. These isolates were subjected to Oxford Nanopore and Illumina whole-genome sequencing, genome assembly, and annotation. Based on whole-genome sequences, the five strains belong to Erysipelotrichaceae bacterium OH741_COT-311, Eubacterium sp. AM28-29, and Faecalitalea cylindroides. The GC content of the five strains ranged from 34.1 to 37.37%. Functional annotation based on the Kyoto encyclopedia of genes and genomes pathways revealed tens to hundreds of strain-specific proteins among different strains, and even between the strains showing high 16S rRNA gene sequence identity. Prediction analysis of carbohydrate metabolism revealed different capacities for metabolizing carbohydrate substrates among Erysipelotrichaceae strains. We identified that genes related to the GalNAc metabolism pathway were enriched in the genomes of all five isolates and 16 Erysipelotrichaceae strains downloaded from GenBank, suggesting the importance of GalNAc metabolism in Erysipelotrichaceae strains. Polysaccharide utilization loci (PUL) analysis revealed that the strains of Erysipelotrichaceae may have the ability to utilize plant polysaccharides. CONCLUSIONS: The present study not only reports the successful isolation of novel Erysipelotrichaceae strains that enrich the cultured strains of Erysipelotrichaceae, but also provided the genome information of Erysipelotrichaceae strains for further studying the function roles of Erysipelotrichaceae in host phenotypes.
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Firmicutes/genética , Genoma Bacteriano/genética , Suínos/microbiologia , Animais , Fezes/microbiologia , Firmicutes/isolamento & purificação , RNA Ribossômico 16S/genéticaRESUMO
Pesticide residue is a common problem worldwide. Cypermethrin is a type II pyrethroid pesticide that has been widely used in recent years. It has become a widespread residual pesticide in the environment and agricultural products. The neurotoxicity of cypermethrin remains a matter of concern. However, few studies have evaluated its toxicity on cerebral cortical neurons. As the center of the nervous system, the cerebral cortex is involved in a series of biological processes, such as learning, memory, emotions, and movement. The Nrf2/ARE signaling pathway has been considered to play a protective role in several central nervous system (CNS) diseases. We investigated whether this pathway plays a protective role in cypermethrin-induced apoptosis of the cortical neurons. We established a cypermethrin-induced apoptosis model in the cortical neurons using different cypermethrin doses and different incubation periods. The changes in Nrf2 protein and mRNA expression and its downstream genes HO-1 and NQO1 were detected by quantitative real-time PCR and Western blotting to study the role of the Nrf2/ARE pathway in cypermethrin-induced apoptosis of the cortical neurons. The results showed that the Nrf2/ARE signaling pathway has a protective effect in cypermethrin-induced apoptosis of the cortical neurons. However, this protective effect of the Nrf2/ARE pathway is very limited and is dependent on the exposure dose and exposure period of cypermethrin.
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Fator 2 Relacionado a NF-E2 , Piretrinas , Apoptose , Córtex Cerebral , Neurônios , Estresse Oxidativo , Transdução de SinaisRESUMO
BACKGROUND: Meat production from the commercial crossbred Duroc × (Landrace × Yorkshire) (DLY) pig is predominant in the pork industry, but its meat quality is often impaired by low ultimate pH (pHu). Muscle glycogen level at slaughter is closely associated with pHu and meat technological quality, but its genetic basis remains elusive. The aim of this study was to identify genes and/or causative mutations associated with muscle glycogen level and other meat quality traits by performing a genome-wide association study (GWAS) and additional analyses in a population of 610 DLY pigs. RESULTS: Our initial GWAS identified a genome-wide significant (P = 2.54e-11) quantitative trait locus (QTL) on SSC15 (SSC for Sus scrofa chromosome) for the level of residual glycogen and glucose (RG) in the longissimus muscle at 45 min post-mortem. Then, we demonstrated that a low-frequency (minor allele frequency = 0.014) R200Q missense mutation in the PRKAG3 (RN) gene caused this major QTL effect on RG. Moreover, we showed that the 200Q (RN-) allele was introgressed from the Hampshire breed into more than one of the parental breeds of the DLY pigs. After conditioning on R200Q, re-association analysis revealed three additional QTL for RG on SSC3 and 4, and on an unmapped scaffold (AEMK02000452.1). The SSC3 QTL was most likely caused by a splice mutation (g.8283C>A) in the PHKG1 gene that we had previously identified. Based on functional annotation, the genes TMCO1 on SSC4 and CKB on the scaffold represent promising candidate genes for the other two QTL. There were significant interaction effects of the GWAS tag SNPs at those two loci with PRKAG3 R200Q on RG. In addition, a number of common variants with potentially smaller effects on RG (P < 10-4) were uncovered by a second conditional GWAS after adjusting for the two causal SNPs, R200Q and g.8283C>A. CONCLUSIONS: We found that the RN- allele segregates in the parental lines of our DLY population and strongly influences its meat quality. Our findings also indicate that the genetic basis of RG in DLY can be mainly attributed to two major genes (PRKAG3 and PHKG1), along with many minor genes.
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Proteínas Quinases Ativadas por AMP/genética , Glicogênio/metabolismo , Carne/análise , Músculo Esquelético/metabolismo , Fosforilase Quinase/genética , Suínos/metabolismo , Animais , Estudos de Coortes , Feminino , Qualidade dos Alimentos , Variação Genética , Estudo de Associação Genômica Ampla/veterinária , Masculino , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Subunidades Proteicas/genética , Locos de Características Quantitativas , Especificidade da Espécie , Suínos/genéticaRESUMO
OBJECTIVE: To study the role of Nrf2/ARE signaling pathway in cypermethrin-induced oxidative stress and apoptosis of cerebral cortex neurons in C57BL/6 mice. METHODS: The cortical neurons of C57BL/6 mice were cultured and identified, and a cypermethrin-induced cell injury model was established by treating the cells with 0, 25, 50 and 100 µmol/L of cypermethrin for 48 h. CCK-8 assay was used to analyze the effects of cypermethrin on the cell viability, and the fluorescence probe DCFH-DA was used for detecting intracellular reactive oxygen species (ROS); flow cytometry was performed for determining the apoptosis rate of the cells. The mRNA and protein expression levels of Nrf2 and its downstream genes HO-1 and NQO1 were detected using qPCR and Western blotting. RESULTS: Exposure to cypermethrin at different doses inhibited the viability of the cultured cortical neurons. With the increase of cypermethrin dose, the viability of the neurons decreased progressively, the intracellular ROS and the cell apoptosis rate increased, and the neuronal injury worsened. At the dose of 50 and 100 µmol/L, cypermethrin significantly down-regulated the expressions of HO-1, NQO1 and Nrf2 at both the mRNA and protein levels in the cells (P < 0.01). CONCLUSIONS: Cypermethrin exposure shows a dose-dependent neurotoxicity by inhibiting Nrf2/ARE signaling pathway, down-regulating the expression of Nrf2 and its downstream genes HO-1, NQO1 mRNA and protein, and inducing oxidative damage and apoptosis in primary mouse cortical neurons, .
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Transdução de Sinais , Animais , Hidrolases de Éster Carboxílico , Córtex Cerebral , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2 , Neurônios , PiretrinasRESUMO
Only one crystal form of metoprolol succinate (Form I) was reported during previous researches and production. In this study, a new polymorph of metoprolol succinate (here named as Form II) was discovered and investigated by X-ray diffraction, thermoanalysis and infrared spectroscopy. The results show its crystal structure and thermal properties are significantly different with Form I. Compared with Form I, Form II exhibits specific diffraction pattern, lower melting temperature and weaker hydrogen bond effect. The thermostability testing suggests Form II is a metastable crystal form and will gradually transform into Form I undergoing treatment of high temperature and humidity. Metastable crystal form generally has better dissolubility than its corresponding stable form. Subsequent measurement also verified that Form II can dissolve in the water more quickly than Form I.