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1.
J Am Chem Soc ; 146(15): 10822-10832, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591182

RESUMO

Cerium-stabilized zirconia (Ce1-xZrxOy, CZO) is renowned for its superior oxygen storage capacity (OSC), a key property long believed to be beneficial to catalytic oxidation reactions. However, 50% Ce-containing CZO recorded with the highest OSC has disappointingly poor performance in catalytic oxidation reactions compared to those with higher Ce contents but lower OSC ability. Here, we employ global neural network (G-NN)-based potential energy surface exploration methods to establish the first ternary phase diagram for bulk structures of CZO, which identifies three critical compositions of CZO, namely, 50, 60, and 80% Ce-containing CZO that are thermodynamically stable under typical synthetic conditions. 50% Ce-containing CZO, although having the highest OSC, exhibits the lowest O vacancy (Ov) diffusion rate. By contrast, 60% Ce-containing CZO, despite lower OSC (33.3% OSC compared to that of 50% Ce-containing CZO), reaches the highest Ov diffusion ability and thus offers the highest CO oxidation catalytic performance. The physical origin of the high performance of 60% Ce-containing CZO is the abundance of energetically favorable Ov pairs along the ⟨110⟩ direction, which reduces the energy barrier of Ov diffusion in the bulk and promotes O2 activation on the surface. Our results clarify the long-standing puzzles on CZO and point out that 60% Ce-containing CZO is the most desirable composition for typical CZO applications.

2.
Molecules ; 29(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38611855

RESUMO

Quinoa, known as the "golden grain" for its high nutritional value, has polysaccharides as one of its sources of important nutrients. However, the biological functions of quinoa polysaccharides remain understudied. In this study, two crude polysaccharide extracts of quinoa (Q-40 and Q-60) were obtained through sequential precipitation with 40% and 60% ethanol, with purities of 58.29% (HPLC) and 62.15% (HPLC) and a protein content of 8.27% and 9.60%, respectively. Monosaccharide analysis revealed that Q-40 contained glucose (Glc), galacturonic acid (GalA), and arabinose (Ara) in a molar ratio of 0.967:0.027:0.006. Q-60 was composed of xylose (xyl), arabinose (Ara), galactose, and galacturonic acid (GalA) with a molar ratio of 0.889:0.036:0.034:0.020. The average molecular weight of Q-40 ranged from 47,484 to 626,488 Da, while Q-60 showed a range of 10,025 to 47,990 Da. Rheological experiments showed that Q-40 exhibited higher viscosity, while Q-60 demonstrated more elastic properties. Remarkably, Q-60 showed potent antioxidant abilities, with scavenging rates of 98.49% for DPPH and 57.5% for ABTS. Antibacterial experiments using the microdilution method revealed that Q-40 inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), while Q-60 specifically inhibited MRSA. At lower concentrations, both polysaccharides inhibited MDA (MD Anderson Cancer Center) cell proliferation, but at higher concentrations, they promoted proliferation. Similar proliferation-promoting effects were observed in HepG2 cells. The research provides important information in the application of quinoa in the food and functional food industries.


Assuntos
Chenopodium quinoa , Ácidos Hexurônicos , Staphylococcus aureus Resistente à Meticilina , Arabinose , Escherichia coli , Grão Comestível
3.
Arch Microbiol ; 206(4): 171, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491219

RESUMO

A Gram-negative, facultatively anaerobic, short rod-shaped bacterium, designated as strain HZ0627T, was isolated from the appendiceal pus of a patient with appendicitis in Yongzhou, Hunan, China. This strain was subjected to comprehensive phenotypic, phylogenetic, and genomic analyses using polyphasic taxonomic methods. Phylogenetic analysis of the 16S rRNA gene sequence revealed that this strain belonged to the genus Proteus and the family Morganellaceae, whereas that based on the rpoB gene sequence and phylogenomic analysis demonstrated that this strain was distinctly separated from other type strains of Proteus species. Moreover, whole-genome-based analyses, including in silico DNA-DNA hybridization (isDDH) and average nucleotide identity (ANI), revealed that strain HZ0627T had much lower isDDH rates (24.5-55.6%) and ANI (82.04-93.90%) than those of the thresholds (i.e., 70% and 95%, respectively) for species delineation, when compared to the type strains of other Proteus species. The cellular fatty acid profile of strain HZ0627T was dominated by C16:0 (34.5%), cyclo C17:0 (25.8%), C14:0 (12.6%), C16:1 iso I/14:0 3-OH (7.7%), C18:1ω7c/18:1ω6c (6.5%), and C16:1ω7c/16:1ω6c (4.9%), which clearly differentiated it from the documented type strains of Proteus species. In addition, several specific physiological traits, including optimal growth temperature, tolerance to sodium chloride, and carbon source utilization, differed from those of other Proteus species. Therefore, we propose the name Proteus appendicitidis sp. nov. for strain HZ0627T (= CCTCC AB 2022380T = KCTC 92986T), which represents the type strain of this novel Proteus species.


Assuntos
Apendicite , Humanos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Proteus/genética , Ácidos Graxos/análise , China , DNA , Supuração , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Hibridização de Ácido Nucleico
4.
BMC Microbiol ; 24(1): 91, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500062

RESUMO

BACKGROUND: Probiotics are a potentially effective therapy for inflammatory bowel disease (IBD); IBD is linked to impaired gut microbiota and intestinal immunity. However, the utilization of an antibiotic cocktail (Abx) prior to the probiotic intervention remains controversial. This study aims to identify the effect of Abx pretreatment from dextran sulfate sodium (DSS)-induced colitis and to evaluate whether Abx pretreatment has an enhanced effect on the protection of Clostridium butyricum Miyairi588 (CBM) from colitis. RESULTS: The inflammation, dysbiosis, and dysfunction of gut microbiota as well as T cell response were both enhanced by Abx pretreatment. Additionally, CBM significantly alleviated the DSS-induced colitis and impaired gut epithelial barrier, and Abx pretreatment could enhance these protective effects. Furthermore, CBM increased the benefit bacteria abundance and short-chain fatty acids (SCFAs) level with Abx pretreatment. CBM intervention after Abx pretreatment regulated the imbalance of cytokines and transcription factors, which corresponded to lower infiltration of Th1 and Th17 cells, and increased Th2 cells. CONCLUSIONS: Abx pretreatment reinforced the function of CBM in ameliorating inflammation and barrier damage by increasing beneficial taxa, eliminating pathogens, and inducing a protective Th2 cell response. This study reveals a link between Abx pretreatment, microbiota, and immune response changes in colitis, which provides a reference for the further application of Abx pretreatment before microbiota-based intervention.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Probióticos , Humanos , Animais , Camundongos , Antibacterianos/efeitos adversos , Células Th2 , Células Th17 , Colite/induzido quimicamente , Colite/prevenção & controle , Probióticos/farmacologia , Inflamação , Imunidade , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
5.
Front Genet ; 15: 1197151, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38380423

RESUMO

Background and aims: Defective enzymes, cofactors, or transporters of metabolic pathways cause inherited metabolic disorders (IMDs), a group of genetic disorders. Several IMDs have serious consequences for the affected neonates. Newborn screening for IMDs is conducted by measuring specific metabolites between 3 and 7 days of life. Herein, we analyzed the incidence, spectrum, and genetic characteristics of IMDs in newborns in the Zhuzhou area. Methods: Tandem mass spectrometry was conducted on 90,829 newborns who were admitted to the Women and Children Healthcare Hospital of Zhuzhou and requested for screening for IMDs. These newborns were subsequently subjected to next-generation sequencing and further validated using Sanger sequencing. Results: 30 IMDs cases were found in 90,829 cases of newborns screened for IMDs, and the overall incidence was 1/3,027. The incidence of amino acid, organic acid, fatty acid oxidation and urea cycle disorders were 1/8,257, 1/18,165, 1/7,569, and 1/45,414, respectively. Additionally, 9 cases of maternal IMDs were found in our study, and unreported gene mutations of 3 cases IMDs were identified. Conclusion: Our data indicated that IMDs are never uncommon in zhuzhou, meanwhile, we also found that primary carnitine deficiency was the only disorder of fatty acid oxidation in Zhuzhou, and the incidence (1/7,569) was higher than the national level, organic acid metabolic diseases are mostly inherited. Therefore, our study has clarified the disease spectrum and genetic backgrounds, contributing to the treatment and prenatal genetic counseling of these disorders in this region.

6.
Dalton Trans ; 53(6): 2762-2769, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38226665

RESUMO

The hydrogen oxidation reaction is an important process in anion exchange membrane fuel cells with alkaline solutions. The pursuit of efficient catalysts for alkaline hydrogen oxidation has attracted considerable attention. In this study, we present a precursor route for the synthesis of a new Ir-based catalyst (Ir-Ni/NiO/C), in which Ir nanoclusters were immobilized on the generated Ni/NiO/C support derived from a metal-organic framework. The small size of Ir clusters facilitates the exposure of catalytically active sites. The electronic interplay between the Ir nanoclusters and the Ni/NiO/C support optimized the hydrogen binding energy (HBE) and hydroxide binding energy (OHBE) on the surface, which is unattainable on the contrasting Ir-C, Ir-Ni/C, and Ir-NiO/C products. The optimized catalyst shows excellent mass activity for alkaline hydrogen oxidation, which is 3.1 times that of the Pt/C catalyst. This study presents a promising pathway for the development of advanced HOR catalysts.

7.
J Invest Surg ; 37(1): 2302564, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38234036

RESUMO

PURPOSE: Limited attention was paid to focus on rectal melanomas (RM). This study aimed to evaluate the survival rate and prognostic factors of RM. METHODS: The data for patients with RM from Surveillance, Epidemiology, and End Results (SEER) database were used to analyze tumor survival. Kaplan-Meier method and log-rank test were employed to estimate cancer-specific survival (CSS) and overall survival (OS). A nomogram was established based on the risk factors of survival by the forest plot for multivariate Cox regression analysis. Receiver operating characteristic (ROC) and calibration curve were conducted for validation. RESULTS: A total of 187 patients with RM were selected to perform survival analyses. The median survival time of OS was 12 months (range: 0-146 months), and the median survival time of CSS was 12 months (range: 0-74 months). Patients' age, tumor size, stage, the number of nodes examined, surgery, and radiation were identified as prognostic indicators for CSS by the forest plot for multivariate Cox regression analysis. The nomogram was validated as a reliable model for CSS. CONCLUSION: Clinicopathologic relevance with tumor prognosis was confirmed in this study. Our nomogram can provide a relatively accurate prediction of the survival rate of patients with RM.


Assuntos
Melanoma , Neoplasias Retais , Humanos , Estados Unidos/epidemiologia , Melanoma/diagnóstico , Melanoma/epidemiologia , Prognóstico , Neoplasias Retais/epidemiologia , Neoplasias Retais/terapia , Nomogramas , Bases de Dados Factuais
8.
Sci Rep ; 14(1): 1614, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238351

RESUMO

In this study, a accurate, rapid quantitative PCR method for the simultaneous detection of 4 kinds of pathogenic bacteria in water was established, and the distribution of pathogenic bacteria in surface waters with different levels of pollution (Yulin region, China) was detected. The results showed that the detection accuracy was 94%; the detection limit was 2.7 in bacterial cells. Salmonella enterica subsp. enterica serovar typhimurium and Salmonella dysenteria were always present in water when the universal primer for pathogenic bacteria abundance detection was greater than 104 copies 100 mL-1. When the detection value is lower than 104 copy 100 mL-1, the bacteria in the water are rarely pathogenic bacteria, so the detection value of 104 copy 100 mL-1 can be used as a new indicator of waterborne pathogen pollution.


Assuntos
Bactérias , Salmonella typhimurium , Bactérias/genética , Poluição da Água , China
9.
Apoptosis ; 29(3-4): 331-343, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37848671

RESUMO

Tumor immune escape is an important manner for colon cancer to escape effective killing by immune system. Currently, the immune checkpoint PD-1/PD-L1-targeted immunotherapy has emerged as a promising therapeutic strategy in colon cancer. Here, present work aims to investigate the biological function of N6-methyladenosine (m6A) reader insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1) in regulating colon cancer's immune escape and CD8 + T cells-mediated tumor cytotoxicity and apoptosis. Results illustrated that IGF2BP1 was closely correlated to the colon cancer patients' poor clinical outcome. Functionally, upregulation of IGF2BP1 suppressed the CD8+ T-cells mediated antitumor immunity through reducing their tumor cytotoxicity. Mechanistically, MeRIP-Seq revealed that programmed death ligand 1 (PD-L1) mRNA had a remarkable m6A modified site on 3'-UTR genomic. Moreover, PD-L1 acted as the target of IGF2BP1, which enhanced the stability of PD-L1 mRNA. Overall, these results indicated that IGF2BP1 targeted PD-L1 to accelerate the immune escape in colon cancer by reducing CD8 + T cells-mediated tumor cytotoxicity in m6A-dependent manner. The findings demonstrate the potential of m6A-targeted immune checkpoint blockade in colon cancer, providing a novel insight for colon cancer immune escape and antitumor immunity in further precise treatment.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias do Colo , Humanos , Linfócitos T CD8-Positivos/metabolismo , Antígeno B7-H1/genética , Apoptose/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , RNA Mensageiro/metabolismo
11.
Complement Ther Med ; 80: 103009, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38081432

RESUMO

OBJECTIVE: To understand research advances and frontiers of acupuncture regulation on the autonomic nervous system (ANS) over the past decade through a bibliometric analysis. METHODS: Publications related to acupuncture regulation on the ANS were retrieved from the Web of Science Core Collection (WoSCC) database. CiteSpace software was used to analyze the datasets and generate knowledge maps. RESULTS: A total of 445 relevant publications published between 2013 and 2022 were included in this bibliometric analysis. The number of annual publications fluctuated from 2013 to 2016 but increased gradually from 2016 to 2022. China produced the highest number of publications, while the USA established the most extensive cooperation relationships. China Academy of Chinese Medical Science was the most productive institution. Chen Jiande D.Z. was the most prolific author and Rong Peijing holds the most extensive cooperation network. Han Jisheng was the most co-cited author. Relevant research involved mechanism exploration and clinical efficacy research, and "anti-inflammatory effect" was the most active research topic, especially cholinergic anti-inflammatory mechanisms. The most cited references mainly focused on inflammation. Gastrointestinal and cardiovascular disorders were the most active medical conditions studied in this field. CONCLUSIONS: Research related to acupuncture regulation on the ANS mainly focused on anti-inflammation, and regulating gastrointestinal and cardiovascular function over the past decade. However, the mechanisms of the autonomic effects of acupuncture need further investigation. High-quality clinical studies are required to determine the optimal parameters of acupuncture for clinical application.


Assuntos
Terapia por Acupuntura , Medicina Tradicional do Leste Asiático , Humanos , Sistema Nervoso Autônomo , Bibliometria , Anti-Inflamatórios
12.
Int J Biol Macromol ; 258(Pt 2): 128833, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128806

RESUMO

Natural polysaccharides exhibit numerous beneficial properties, such as antioxidant, antitumor, hypoglycemic, and hypolipidemic activities. Moringa oleifera seeds are of high dietary and therapeutic value which drew a lot of attention. However, the regulation effect on anti-inflammatory activity of polysaccharides remains to be studied. Herein, novel bioactive polysaccharides (MOSP-1) were extracted from Moringa oleifera seeds, and the anti-inflammatory properties of MOSP-1 were uncovered. Ultrasound-assisted extraction (UAE) was used to prepare the polysaccharides with optimized conditions (70 °C, 43 min, and liquid-solid-ratio 15 mL/g). Then, DEAE-Sepharose Fast Flow columns were applied to isolate and purify MOSP-1. Rhamnose, arabinose, galactose, and glucose were identified as the monosaccharide constituents of MOSP-1, with a molecular weight of 5.697 kDa. Their proportion in molarity was 1:0.183:0.108:0.860 and 8 types of glycosidic linkages were discovered. Bioactive assays showed that MOSP-1 possessed scavenging activities against DPPH and ABTS radicals, confirming its potential antioxidation efficacy. In vitro experiments revealed that MOSP-1 could reduce the expression of inflammation-related cytokines, inhibit the activation of ERK, JNK, and p38 (the MAPK signaling pathway), and enhance phagocytic functions. This study indicates that polysaccharides (MOSP-1) from Moringa oleifera seeds with anti-inflammatory properties may be used for functional food and pharmaceutical product development.


Assuntos
Moringa oleifera , Moringa oleifera/química , Ultrassom , Polissacarídeos/química , Antioxidantes/química , Anti-Inflamatórios , Sementes/química
13.
Anal Chem ; 96(1): 41-48, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38100715

RESUMO

In this work, based on boron nitride quantum dots (BNQDs) as energy donors and MnO2@MWCNTs-COOH as energy receptors, we designed an efficient electrochemiluminescence resonance energy transfer (ECL-RET) immunosensor for the detection of amyloid-ß (Aß42) protein, a biomarker of Alzheimer's disease (AD). First, the signal amplification of a ternary ECL system composed of BNQDs (as the ECL emitter), K2S2O8 (as the coreactant), and silver metal-organic gels (AgMOG, as the coreaction accelerator) was realized, and PDDA as stabilizer was added, a strong and stable initial ECL signal was obtained. AgMOG could not only support a large amount of BNQDs and Aß42 capture antibody (Ab1) through Ag-N bond but also exhibit excellent ECL catalytic performance and enhance the luminescent intensity of BNQDs@PDDA-K2S2O8 system. In addition, due to the broad absorption spectrum of MnO2@MWCNTs-COOH and the extensive overlap with the ECL emission spectrum of BNQDs, the quenching probe Ab2-MnO2@MWCNTs-COOH could be introduced into the ternary system through a sandwich immune response. On this basis, the signal on-off ECL immunosensor was constructed to achieve the ultrasensitive detection of Aß42 through signal transformation. Under the optimal conditions, the prepared ECL biosensor manifested a wide linear range (10 fg/mL-100 ng/mL) with a detection limit of 2.89 fg/mL and showed excellent stability, selectivity, and repeatability, which provided an effective strategy for the ultrasensitive detection of biomarkers in clinical analysis.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Pontos Quânticos , Pontos Quânticos/química , Peptídeos beta-Amiloides/análise , Medições Luminescentes , Compostos de Manganês/química , Óxidos , Imunoensaio , Transferência de Energia , Técnicas Eletroquímicas , Limite de Detecção , Nanopartículas Metálicas/química
14.
Anal Chem ; 95(50): 18436-18442, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38058120

RESUMO

Two-dimensional (2D) iron/cobalt metal-organic framework nanosheets (Fe/Co-MOF NSs) were synthesized via the cooperative self-assembly reaction of Fe3+/Co2+ and terephthalic acid at room temperature. The as-prepared 2D Fe/Co-MOF NSs display superior performance in catalysis of the chemiluminescence (CL) reaction between luminol and H2O2. The CL spectrum, UV-vis absorption spectroscopy, radical scavenger experiments, and electron spin resonance (ESR) spectroscopy are utilized to research the possible CL mechanism of the luminol-H2O2-Fe/Co-MOF NSs system. All results indicate that Fe/Co-MOF NSs present outstanding peroxidase-like activity and could catalyze H2O2 to produce 1O2, O2·-, and ·OH, which could react rapidly with the luminol anion radical and result in strong CL. With the highly efficient CL of the luminol-H2O2-Fe/Co-MOF NSs system, a sensitive sensor for the detection of dopamine (DA) is developed based on the inhibitory effect of DA on the CL intensity. Good linearity over the range of 50-800 nM is achieved with a limit of detection of 20.88 nM (S/N = 3). This research demonstrates that 2D Fe/Co-MOF NSs is a highly effective catalyst for luminol CL reaction and has great application potential in the CL field.

15.
Int Wound J ; 21(3): e14523, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38050653

RESUMO

In a meta-study, we evaluated the effectiveness and security of the combination of topical anaesthetic and dexmedetomidine in the treatment of postoperative pain in patients with lumbar disease. Four databases were systematically searched for possible related articles. Only English-language research was taken into account on the Internet. Furthermore, we only took into account the studies that were published prior to 2023. Only those that fulfilled the eligibility criteria were considered: (1) in adults who were about to undergo spine operation, (2) dexmedetomidine combined with local anaesthesia, (3) Visual Analog Scale scores at 4 and 24 h after the event and (4) this was a randomized or nonrandomized, controlled study. The meta-analysis was carried out with Revman 5.3 software. A ROBINS-I-based instrument was used to evaluate controlled studies. All trials were synthesized by computing the end results with either a fixed or a random effect model, which was dependent on statistical diversity. Five trials showed a marked reduction in wound pain at 4 h after the operation in patients who were treated with dexmedetomidine for lumbar spinal surgery (MD, -0.81; 95% CI, -1.24, -0.35; p = 0.0005). In the case of lumbar spinal operations, the addition of dexmedetomidine to the postoperative treatment resulted in a marked reduction in the pain at 24 h post-operation (MD, -0.64; 95% CI, -0.79, -0.48; p < 0.0001). The quality of the data we evaluated was 'moderate' to 'good'; thus, we have limited confidence in the impact estimation, and the actual impact might be significantly different from what we had expected. Additional studies should concentrate on practices that are well known to cause severe postoperative pain, especially for cases where the improvement of pain management may lead to substantial clinical benefits in terms of reduction of morbidity or cost-effectiveness in terms of quicker healing and release.

16.
Zool Stud ; 62: e47, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965299

RESUMO

octurnal animals use their vision and acute hearing to adapt to the nighttime environment. Light pollution has become a serious problem for nocturnal animals in coastal areas, especially nesting sea turtles and sea turtle hatchlings. Hatchlings use visual clues to find the ocean. However, when the artificial light is stronger than the natural light, hatchlings become either misoriented, disoriented or both. Due to rapid tourism development on Lanyu Island, new sources of light pollution, especially streetlights, pose a serious threat to sea turtle hatchlings. In this study, we used a portable lamp constructed by Liteon Inc. on a circular area of a turtle nesting beach to see how artificial light sources could affect green turtle hatchlings' sea finding behavior. In the experiments, we tested hatchling behavior under different lamp settings (strong or weak light intensity; white or yellow light; lamp shield presence or absence) and moon visibilities (moonlit or moonless). The hatchlings' crawling tracks and locations at the end of the trials were recorded. Results showed that the light intensity had no effect on hatchling sea finding behavior. White light had a stronger impact on hatchling sea finding behavior than yellow light. When the lamp shield was installed on moonlit nights, more hatchings were able to find the sea under both white and yellow lights. Thus, it is recommended that light shields be installed on the streetlights of Lanyu Island in order to protect the sea turtle hatchlings effectively.

17.
Front Microbiol ; 14: 1293206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029151

RESUMO

Paraclostridium bifermentans (P.b) is an emerging human pathogen that is phylogenomically close to Paeniclostridium sordellii (P.s), while their populational genomic features and virulence capacity remain understudied. Here, we performed comparative genomic analyses of P.b and compared their pan-genomic features and virulence coding profiles to those of P.s. Our results revealed that P.b has a more plastic pangenome, a larger genome size, and a higher GC content than P.s. Interestingly, the P.b and P.s share similar core-genomic functions, but P.b encodes more functions in nutrient metabolism and energy conversion and fewer functions in host defense in their accessory-genomes. The P.b may initiate extracellular infection processes similar to those of P.s and Clostridium perfringens by encoding three toxin homologs (i.e., microbial collagenase, thiol-activated cytolysin, phospholipase C, which are involved in extracellular matrices degradation and membrane damaging) in their core-genomes. However, P.b is less toxic than the P.s by encoding fewer secretion toxins in the core-genome and fewer lethal toxins in the accessory-genome. Notably, P.b carries more toxins genes in their accessory-genomes, particularly those of plasmid origin. Moreover, three within-species and highly conserved plasmid groups, encoding virulence, gene acquisition, and adaptation, were carried by 25-33% of P.b strains and clustered by isolation source rather than geography. This study characterized the pan-genomic virulence features of P.b for the first time, and revealed that P. bifermentans is an emerging pathogen that can threaten human health in many aspects, emphasizing the importance of phenotypic and genomic characterizations of in situ clinical isolates.

18.
J Glob Antimicrob Resist ; 35: 268-270, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866682

RESUMO

OBJECTIVES: Prevotella bivia is a species that commonly colonizes various human body sites, and it is associated with lots of human infections. However, until now, no complete genome sequence of this species has been published. Here, we assembled the first complete genome of P. bivia from a clinically derived strain PLW0727, to characterize its general genomic features, and to profile the capacity in encoding antibiotic resistance and virulence factors. METHODS: Whole-genome sequencing was performed using Illumina and Nanopore platforms. Hybrid assembly was conducted using flye v2.9.1 and Unicycler v0.4.9b. Assembly completeness was assessed using CheckM v1.0.12. Comprehensive genome annotation was performed using eggNOG-mapper v2.1.5 and PATRIC v3.6.10. RESULTS: The complete genome of PLW0727 consists of two circular chromosomes, chr1 and chr2, exhibiting a completeness of 99.66%, a G+C content of 39.5%, and a total size of 2.43 Mb. Chr1 and chr2 have lengths of 1 272 652 bp and 1 155 021 bp, harbouring 1 132 CDSs and 1 055 CDSs, respectively. Completion of the genome significantly reduced the proportion of hypothetical CDS annotations compared with the draft genomes. A gene-encoding antibiotic resistance to beta-lactams (i.e., cfxA3) has been annotated in chr2. By providing the genome sequence, strain PLW0727 was identified as a human pathogen with a probability of 0.614 using the PathogenFinder. Furthermore, genes involved in virulence-related functions, including host cell adherence and capsule immune modulation were also annotated. CONCLUSIONS: This study assembles the first complete genome for P. bivia, providing valuable genomic insights into its phylogeny, pathogenicity, and antibiotic resistance. These findings have important implications for the clinical management and prevention of P. bivia infections.


Assuntos
Genoma Bacteriano , Prevotella , Humanos , Prevotella/genética , Sequenciamento Completo do Genoma , Genômica
19.
J Biotechnol ; 376: 53-63, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37813281

RESUMO

Quinoline is a hard-to-degrade organic compound widely found in coal chemical wastewater, that seriously affects the ecological environment and human health. A number of biochemical methods are already available for quinoline degradation, but the use of microbial community sensing for quinoline degradation has not been studied in depth. Therefore, this paper focuses on the enhanced mechanism of quorum-sensing signaling molecules in the biofilm formation process during quinoline degradation by functional strains of bacteria. In this paper, the effects of the signal molecules C4-HSL and C6-HSL on the adhesion ability, colony diameter, biofilm formation ability and biofilm morphology of functional strains of quinoline degrading bacteria (Ochrobactrum sp., LC-1) were investigated, and the results showed that both signal molecules promoted the biofilm formation process during the degradation of quinoline by exhibiting an efficient biofortification effect. Both signal molecules could enhance the colony diameter of strain LC-1, where C4-HSL could enhance the biomass of strain LC-1 and stimulate the secretion of extracellular polysaccharides; and C6-HSL could induce the enhancement of adhesion performance and the secretion of extracellular proteins from strain LC-1; both molecules together enhanced the biofilm formation process of strain LC-1. This study has practical application in the degradation of quinoline in coal chemical wastewater.


Assuntos
Quinolinas , Águas Residuárias , Humanos , Biofilmes , Percepção de Quorum , Bactérias , Quinolinas/farmacologia , Carvão Mineral
20.
J Anim Sci Biotechnol ; 14(1): 135, 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37805513

RESUMO

Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branched-chain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry.

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