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1.
Int J Mol Sci ; 25(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38612440

RESUMO

Salinity is one of the most serious threats to sustainable agriculture. The Salt Overly Sensitive (SOS) signaling pathway plays an important role in salinity tolerance in plants, and the SOS2 gene plays a critical role in this pathway. Mulberry not only has important economic value but also is an important ecological tree species; however, the roles of the SOS2 gene associated with salt stress have not been reported in mulberry. To gain insight into the response of mulberry to salt stress, SOS2 (designated MulSOS2) was cloned from mulberry (Morus atropurpurea Roxb), and sequence analysis of the amino acids of MulSOS2 showed that it shares some conserved domains with its homologs from other plant species. Our data showed that the MulSOS2 gene was expressed at different levels in different tissues of mulberry, and its expression was induced substantially not only by NaCl but also by ABA. In addition, MulSOS2 was exogenously expressed in Arabidopsis, and the results showed that under salt stress, transgenic MulSOS2 plants accumulated more proline and less malondialdehyde than the wild-type plants and exhibited increased tolerance to salt stress. Moreover, the MulSOS2 gene was transiently overexpressed in mulberry leaves and stably overexpressed in the hairy roots, and similar results were obtained for resistance to salt stress in transgenic mulberry plants. Taken together, the results of this study are helpful to further explore the function of the MulSOS2 gene, which provides a valuable gene for the genetic breeding of salt tolerance in mulberry.


Assuntos
Arabidopsis , Morus , Tolerância ao Sal/genética , Morus/genética , Melhoramento Vegetal , Estresse Salino , Agricultura , Plantas Geneticamente Modificadas
2.
Physiol Plant ; 176(2): e14309, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659152

RESUMO

Although microRNAs (miRNAs) regulate the defense response of a variety of plant species against a variety of pathogenic fungi, the involvement of miRNAs in mulberry's defense against Botrytis cinerea has not yet been documented. In this study, we identified responsive B. cinerea miRNA mno-miR164a in mulberry trees. After infection with B. cinerea, the expression of mno-miR164a was reduced, which was fully correlated with the upregulation of its target gene, MnNAC100, responsible for encoding a transcription factor. By using transient infiltration/VIGS mulberry that overexpressed mno-miR164a or knocked-down MnNAC100, our study revealed a substantial enhancement in mulberry's resistance to B. cinerea when mno-miR164a was overexpressed or MnNAC100 expression was suppressed. This enhancement was accompanied by increased catalase (CAT) activity and reduced malondialdehyde (MDA) content. In addition, mno-miR164a-mediated inhibition of MnNAC100 enhanced the expression of a cluster of defense-related genes in transgenic plants upon exposure to B. cinerea. Meanwhile, MnNAC100 acts as a transcriptional repressor, directly suppressing the expression of MnPDF1.2. Our study indicated that the mno-miR164a-MnNAC100 regulatory module manipulates the defense response of mulberry to B. cinerea infection. This discovery has great potential in breeding of resistant varieties and disease control.


Assuntos
Botrytis , Resistência à Doença , Regulação da Expressão Gênica de Plantas , MicroRNAs , Morus , Doenças das Plantas , Proteínas de Plantas , Morus/genética , Morus/microbiologia , Botrytis/fisiologia , Botrytis/patogenicidade , MicroRNAs/genética , MicroRNAs/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Resistência à Doença/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Plantas Geneticamente Modificadas , Malondialdeído/metabolismo
3.
Front Cell Infect Microbiol ; 14: 1351607, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562965

RESUMO

Objective: Thrombocytopenia is commonly associated with infectious diseases and serves as an indicator of disease severity. However, reports on its manifestation in conjunction with Klebsiella pneumoniae liver abscess (KPLA) are scarce. The present study sought to elucidate the correlation between thrombocytopenia and KPLA severity and delve into the etiological factors contributing to the incidence of thrombocytopenia. Materials and methods: A retrospective analysis of the clinical data from patients with KPLA admitted between June 2012 and June 2023 was performed. Baseline characteristics, biochemical assessments, therapeutic interventions, complications, and clinical outcomes were compared between patients with and without thrombocytopenia. To investigate the potential etiologies underlying thrombocytopenia, the association between platelet count reduction and thrombophlebitis was examined, with a particular focus on platelet consumption. Furthermore, bone marrow aspiration results were evaluated to assess platelet production anomalies. Results: A total of 361 KPLA patients were included in the study, among whom 60 (17%) had concurrent thrombocytopenia. Those in the thrombocytopenia group exhibited significantly higher rates of thrombophlebitis (p = 0.042), extrahepatic metastatic infection (p = 0.01), septic shock (p = 0.024), admissions to the intensive care unit (p = 0.002), and in-hospital mortality (p = 0.045). Multivariate analysis revealed that thrombocytopenia (odds ratio, 2.125; 95% confidence interval, 1.114-4.056; p = 0.022) was independently associated with thrombophlebitis. Among the thrombocytopenic patients, eight underwent bone marrow aspiration, and six (75%) had impaired medullar platelet production. After treatment, 88.6% of thrombocytopenic patients (n = 47) demonstrated recovery in their platelet counts with a median recovery time of five days (interquartile range, 3-6 days). Conclusions: Thrombocytopenia in patients with KPLA is indicative of increased disease severity. The underlying etiologies for thrombocytopenia may include impaired platelet production within the bone marrow and augmented peripheral platelet consumption as evidenced by the presence of thrombophlebitis.


Assuntos
Infecções por Klebsiella , Abscesso Hepático , Trombocitopenia , Tromboflebite , Humanos , Estudos Retrospectivos , Klebsiella pneumoniae , Infecções por Klebsiella/complicações , Infecções por Klebsiella/epidemiologia , Abscesso Hepático/epidemiologia , Trombocitopenia/complicações , Gravidade do Paciente , Tromboflebite/complicações
4.
Adv Mater ; 36(14): e2311537, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38174591

RESUMO

Three kinds of coronaviruses are highly pathogenic to humans, and two of them mainly infect humans through Angiotensin-converting enzyme 2 (ACE2)receptors. Therefore, specifically blocking ACE2 binding at the interface with the receptor-binding domain is promising to achieve both preventive and therapeutic effects of coronaviruses. Alternatively, drug-targeted delivery based on ACE2 receptors can further improve the efficacy and safety of inhalation drugs. Here, these two approaches are innovatively combined by designing a nanoemulsion (NE) drug delivery system (termed NE-AYQ) for inhalation that targets binding to ACE2 receptors. This inhalation-delivered remdesivir nanoemulsion (termed RDSV-NE-AYQ) effectively inhibits the infection of target cells by both wild-type and mutant viruses. The RDSV-NE-AYQ strongly inhibits Severe acute respiratory syndrome coronavirus 2 at two dimensions: they not only block the binding of the virus to host cells at the cell surface but also restrict virus replication intracellularly. Furthermore, in the mouse model of acute lung injury, the inhaled drug delivery system loaded with anti-inflammatory drugs (TPCA-1-NE-AYQ) can significantly alleviate the lung tissue injury of mice. This smart combination provides a new choice for dealing with possible emergencies in the future and for the rapid development of inhaled drugs for the treatment of respiratory diseases.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Animais , Camundongos , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Peptidil Dipeptidase A/farmacologia , Replicação Viral
5.
Acta Pharm Sin B ; 14(1): 350-364, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38261817

RESUMO

Recent clinical studies have shown that mutation of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) gene in cancer cells may be associated with immunosuppressive tumor microenvironment (TME) and poor response to immune checkpoint blockade (ICB) therapy. Therefore, efficiently restoring PTEN gene expression in cancer cells is critical to improving the responding rate to ICB therapy. Here, we screened an adeno-associated virus (AAV) capsid for efficient PTEN gene delivery into B16F10 tumor cells. We demonstrated that intratumorally injected AAV6-PTEN successfully restored the tumor cell PTEN gene expression and effectively inhibited tumor progression by inducing tumor cell immunogenic cell death (ICD) and increasing immune cell infiltration. Moreover, we developed an anti-PD-1 loaded phospholipid-based phase separation gel (PPSG), which formed an in situ depot and sustainably release anti-PD-1 drugs within 42 days in vivo. In order to effectively inhibit the recurrence of melanoma, we further applied a triple therapy based on AAV6-PTEN, PPSG@anti-PD-1 and CpG, and showed that this triple therapy strategy enhanced the synergistic antitumor immune effect and also induced robust immune memory, which completely rejected tumor recurrence. We anticipate that this triple therapy could be used as a new tumor combination therapy with stronger immune activation capacity and tumor inhibition efficacy.

6.
Emerg Microbes Infect ; 13(1): 2294857, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38085548

RESUMO

Campylobacter upsaliensis was the most common Campylobacter species in pets' gastrointestinal tracts and has been isolated from patients with bacteremia, hemolytic-uremic syndrome, spontaneous abortion, and Guillain-Barré syndrome. However, the genetic characteristics and the full extent of its significance as a human pathogen remain to be fully understood. This study involved an investigation for genomic analysis of 154 strains from different sources and additional antimicrobial resistance profiles of 26 strains for this species. The genomes contained 1,558-1,971 CDS and the genome sizes were estimated to vary from 1.53 Mb to 1.86 Mb, with an average GC content of 34.71%. The entire analyzed genomes could be divided into three clades (A, B, and C) based on ANI and phylogenomic analysis. Significantly, nearly all strains in Clade B were isolated from patient samples, and the virulence-related sequences FlgD, GmhA, and CdtC might serve as determining factors for the classification of Clade B. Half of the tested isolates had MIC values over 64 µg mL-1 for nalidixic acid, gentamicin, and streptomycin. Isolates from pets in China carried more resistant elements in the genomes. This study both provided a comprehensive profile of C. upsaliensis for its genomic features and suggested some pathogenic agents for human infection with this species.


Assuntos
Infecções por Campylobacter , Campylobacter upsaliensis , Campylobacter , Humanos , Campylobacter upsaliensis/genética , Infecções por Campylobacter/veterinária , Genômica , China
7.
J Control Release ; 365: 640-653, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042374

RESUMO

To reduce recurrence rate after transurethral resection of bladder tumor, long-term intravesical instillations of Bacillus Calmette-Guérin (BCG) and/or chemotherapeutic drugs is the standard treatment for non-muscle invasive bladder carcinoma. However, the main challenges of intravesical therapy, such as short retention time and poor permeability of drugs in the bladder, often require frequent and high-dose administrations, leading to significant adverse effects and financial burden for patients. Aiming at addressing these challenges, we developed a novel approach, in which the cell-penetrating peptide modified oxaliplatin prodrug liposomes and a low-dose BCG were co-delivered via a viscous chitosan solution (LRO-BCG/CS). LRO-BCG/CS addressed these challenges by significantly improving the retention capability and permeability of chemotherapy agents across the bladder wall. Then, oxaliplatin triggered the immunogenic cell death, and the combination of BCG simultaneously further activated the systemic anti-tumor immune response in the MB49 orthotopic bladder tumor model. As a result, LRO-BCG/CS demonstrated superior anti-tumor efficacy and prolonged the survival time of tumor-bearing mice significantly, even at relatively low doses of oxaliplatin and BCG. Importantly, this combinational chemo-immunotherapy showed negligible side effects, offering a promising and well-tolerated therapeutic strategy for bladder cancer patients.


Assuntos
Pró-Fármacos , Neoplasias da Bexiga Urinária , Humanos , Camundongos , Animais , Vacina BCG , Oxaliplatina/uso terapêutico , Lipossomos/uso terapêutico , Pró-Fármacos/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Administração Intravesical , Imunoterapia , Adjuvantes Imunológicos/uso terapêutico , Recidiva Local de Neoplasia/patologia
8.
Mol Med Rep ; 29(1)2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37975263

RESUMO

Following the publication of this paper, it was drawn to the Editor's attention by a concerned reader that the GAPDH control western blotting data shown in Fig. 4A were strikingly similar to data appearing in different form in another article written by different authors at different research institutes. Owing to the fact that the contentious data in the above article had already been published prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 17: 8385­8390, 2018; DOI: 10.3892/mmr.2018.8887].

9.
Molecules ; 28(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38005212

RESUMO

Solid Oxide Fuel Cell (SOFC) cathodes operating in ambient atmospheric conditions inevitably encounter CO2 contamination, leading to sustained performance deterioration. In this investigation, we examined the impact of CO2 on three variants of (La,Sr)(Co,Fe)O3-δ cathodes and employed the distribution of relaxation times method to distinguish distinct electrochemical processes based on impedance spectra analysis. We meticulously analyzed and discussed the corrosion resistance of these (La,Sr)(Co,Fe)O3-δ cathodes under high CO2 concentrations, relying on the experimental data. Electrochemical impedance spectroscopy results revealed that La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF-6428), La0.4Sr0.6Co0.2Fe0.8O3-δ (LSCF-4628), and La0.4Sr0.6Co0.2Fe0.7Nb0.1O3-δ (LSCFN-46271) cathodes exhibited persistent degradation when exposed to CO2 at temperatures of 650 °C or 800 °C during the durability-testing period. An increase in electrode polarization resistance was observed upon CO2 introduction to the electrode, but electrode performance recovered upon returning to a pure air environment. Furthermore, X-ray diffraction and scanning electron microscopy analyses confirmed that CO2 did not cause permanent damage to the (La,Sr)(Co,Fe)O3-δ cathodes. These findings indicate that the (La,Sr)(Co,Fe)O3-δ cathodes exhibit excellent resistance to CO2-induced corrosion.

10.
Vet Sci ; 10(11)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37999453

RESUMO

The spread of antibiotic resistance genes (ARGs) in the environment exacerbates the contamination of these genes; therefore, the role plants play in the transmission of resistance genes in the food chain requires further research. Giant pandas consume different bamboo parts at different times, which provides the possibility of investigating how a single food source can affect the variation in the spread of ARGs. In this study, metagenomic analysis and the Comprehensive Antibiotic Resistance Database (CARD) database were used to annotate ARGs and the differences in gut microbiota ARGs during the consumption of bamboo shoots, leaves, and culms by captive giant pandas. These ARGs were then compared to investigate the impact of bamboo part consumption on the spread of ARGs. The results showed that the number of ARGs in the gut microbiota of the subjects was highest during the consumption of bamboo leaves, while the variety of ARGs was highest during the consumption of shoots. Escherichia coli, which poses a higher risk of ARG dissemination, was significantly higher in the leaf group, while Klebsiella, Enterobacter, and Raoultella were significantly higher in the shoot group. The ARG risk brought by bamboo shoots and leaves may originate from soil and environmental pollution. It is recommended to handle the feces of giant pandas properly and regularly monitor the antimicrobial and virulence genes in their gut microbiota to mitigate the threat of antibiotic resistance.

11.
Front Microbiol ; 14: 1278268, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881248

RESUMO

Arcobacter was recognized as an emerging enteropathogen and controversies regarding its classification persisted. This study aimed to reevaluate the taxonomy of Arcobacter utilizing the 16S rRNA gene, 23S rRNA gene, single-copy orthologous genes, as well as genomic indices such as Average Nucleotide Identity (ANI) and in silico DNA-DNA hybridization (isDDH). The taxonomy of this genus was reevaluated in this study using multiple indices with a dataset of 371 genomes comprising 34 known species and 14 potentially new species. Good discrimination could be achieved only in some species but not for the species with higher sequence similarity using the comparisons of the 16S rRNA gene and 23S rRNA gene sequences. A high-accuracy phylogenomic approach for Arcobacter was established using 84 single-copy orthologous genes obtained through various bioinformatics methods. One marker gene (gene711), which was found to possess the same distinguishing ability as ANI, isDDH, and single-copy orthologous methods, was identified as a reliable locus for inferring the phylogeny of the genus. The effective species classification was achieved by employing gene711 with a sequence similarity exceeding 96%, even for species like A. cloacae, A. lanthieri, and A. skirrowii, which exhibited ambiguous classification using ANI and isDDH. Additionally, excellent subspecies categorizing among A. cryaerophilus could be distinguished using gene711. In conclusion, this framework strategy had the potential advantage of developing rapid species identification, particularly for highly variable species, providing a novel insight into the behavior and characteristics of Arcobacter.

12.
Front Genet ; 14: 1240581, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37823030

RESUMO

In 2019, two distinct bacterial isolates were independently isolated from the fecal samples of separate dogs in Beijing, China. These cells exhibit microaerobic, are Gram-negative, motile, and possess a characteristic spiral shape with bipolar single flagellum. They display positive results for the oxidase test while being negative for both catalase and urease. These organisms measure approximately 0.2-0.3 µm in width and 4.5-6 µm in length. The colonies are wet, flat, grey, circular, and smooth with sizes ranging from 1 to 2 mm in diameter after 2 days of growth. However, strains may exhibit variations in size and morphology following extended incubation. Phylogenetic analyses based on the 16S rRNA gene and core genome indicated that these two isolates belong to the genus Helicobacter and formed a robust clade that was remains distinctly separate from currently recognized species. These two isolates shared low dDDH relatedness and ANI values with their closest species Helicobacter canis CCUG 32756T, with these values falling below the commonly cutoff values for strains of the same species. The genomic DNA G + C contents of strain XJK30-2 were 44.93 mol%. Comparing the phenotypic and phylogenetic features between these two isolates and their closely related species, XJK30-2 represents a novel species within the genus Helicobacter, for which the name Helicobacter zhangjianzhongii sp. nov. (Type strain XJK30-2T = GDMCC 1.3695T) is proposed.

13.
Microorganisms ; 11(9)2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37764121

RESUMO

Campylobacter is among the four main causes of gastroenteritis worldwide. Most reported Campylobacter infections are caused by C. jejuni and C. coli. However, other emerging Campylobacter pathogens have been recognized as important pathogens in humans and animals. A novel bacterial strain, PS10T, was isolated from the gastric mucous of pigs in 2022 in Beijing, China. The cell was Gram-negative, microaerobic, motile, and negative for catalase, oxidase, and urease. Phylogenetic and phylogenomic analyses based on the 16S rRNA gene and core genome indicated that this isolate belongs to the genus Campylobacter. There were low dDDH relatedness and ANI values shared within this strain and its closest species C. mucosalis below the cut-off values generally recognized for isolates of the same species. The draft genome size of PS10T is 2,240,910 bp in length with a percentage of DNA G+C contents of 37.72%. Comparing the phenotypic and phylogenetic features among this isolate and its related organisms, strain PS10T represents a novel species within the genus Campylobacter, for which the name Campylobacter gastrosuis sp. nov. (Type strain PS10T = GDMCC 1.3686T = JCM 35849T) is proposed.

14.
Entropy (Basel) ; 25(8)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37628199

RESUMO

The transformer-based U-Net network structure has gained popularity in the field of medical image segmentation. However, most networks overlook the impact of the distance between each patch on the encoding process. This paper proposes a novel GC-TransUnet for medical image segmentation. The key innovation is that it takes into account the relationships between patch blocks based on their distances, optimizing the encoding process in traditional transformer networks. This optimization results in improved encoding efficiency and reduced computational costs. Moreover, the proposed GC-TransUnet is combined with U-Net to accomplish the segmentation task. In the encoder part, the traditional vision transformer is replaced by the global context vision transformer (GC-VIT), eliminating the need for the CNN network while retaining skip connections for subsequent decoders. Experimental results demonstrate that the proposed algorithm achieves superior segmentation results compared to other algorithms when applied to medical images.

15.
Front Microbiol ; 14: 1211835, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426007

RESUMO

Introduction: Pyogenic liver abscess (PLA) patients combined with diabetes mellitus (DM) tend to have more severe clinical manifestations than without DM. The mechanism responsible for this phenomenon is not entirely clear. The current study therefore aimed to comprehensively analyze the microbiome composition and metabolome in pus from PLA patients with and without DM, to determine the potential reasons for these differences. Methods: Clinical data from 290 PLA patients were collected retrospectively. We analyzed the pus microbiota using 16S rDNA sequencing in 62 PLA patients. In addition, the pus metabolomes of 38 pus samples were characterized by untargeted metabolomics analysis. Correlation analyses of microbiota, metabolites and laboratory findings were performed to identify significant associations. Results: PLA patients with DM had more severe clinical manifestations than PLA patients without DM. There were 17 discriminating genera between the two groups at the genus level, among which Klebsiella was the most discriminating taxa. The ABC transporters was the most significant differential metabolic pathway predicted by PICRUSt2. Untargeted metabolomics analysis showed that concentrations of various metabolites were significantly different between the two groups and seven metabolites were enriched in the ABC transporters pathway. Phosphoric acid, taurine, and orthophosphate in the ABC transporters pathway were negatively correlated with the relative abundance of Klebsiella and the blood glucose level. Discussion: The results showed that the relative abundance of Klebsiella in the pus cavity of PLA patients with DM was higher than those without DM, accompanied by changes of various metabolites and metabolic pathways, which may be associated with more severe clinical manifestations.

16.
Front Microbiol ; 14: 1152719, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37323906

RESUMO

The prevalence of Campylobacter spp.in pets is a potential concern for human health. However, little is known about the pet-related Campylobacter spp. in China. A total of 325 fecal samples were collected from dogs, cats, and pet foxes. Campylobacter spp. were isolated by culture, and MALDI-TOF MS was used to identify 110 Campylobacter spp. isolates in total. C. upsaliensis (30.2%, 98/325), C. helveticus (2.5%, 8/325), and C. jejuni (1.2%, 4/325) were the three found species. In dogs and cats, the prevalence of Campylobacter spp. was 35.0% and 30.1%, respectively. A panel of 11 antimicrobials was used to evaluate the antimicrobial susceptibility by the agar dilution method. Among C. upsaliensis isolates, ciprofloxacin had the highest rate of resistance (94.9%), followed by nalidixic acid (77.6%) and streptomycin (60.2%). Multidrug resistance (MDR) was found in 55.1% (54/98) of the C. upsaliensis isolates. Moreover, 100 isolates, including 88 C. upsaliensis, 8 C. helveticus, and 4 C. jejuni, had their whole genomes sequenced. By blasting the sequence against the VFDB database, virulence factors were identified. In total, 100% of C. upsaliensis isolates carried the cadF, porA, pebA, cdtA, cdtB, and cdtC genes. The flaA gene was present in only 13.6% (12/88) of the isolates, while the flaB gene was absent. By analyzing the sequence against the CARD database, we found that 89.8% (79/88) of C. upsaliensis isolates had antibiotic target alteration in the gyrA gene conferring resistance to fluoroquinolone, 36.4% (32/88) had the aminoglycoside resistance gene, and 19.3% (17/88) had the tetracycline resistance gene. The phylogenetic analysis using the K-mer tree method obtained two major clades among the C. upsaliensis isolates. All eight isolates in subclade 1 possessed the gyrA gene mutation, the aminoglycoside and tetracycline resistance genes, and were phenotypically resistant to six classes of antimicrobials. It has been established that pets are a significant source of Campylobacter spp. strains and a reservoir for them. This study is the first to have documented the presence of Campylobacter spp. in pets in Shenzhen, China. In this study, C. upsaliensis of subclade 1 required additional attention due to its broad MDR phenotype and relatively high flaA gene prevalence.

17.
J Infect Dis ; 228(8): 1127-1136, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37208895

RESUMO

BACKGROUND: Klebsiella pneumoniae liver abscess (KPLA) with extrahepatic migratory infections is defined as invasive KPLA (IKPLA). The type VI secretion system (T6SS) is involved in the pathogenesis of KPLA. We hypothesized that T6SS plays a role in IKPLA. METHODS: 16S ribosomal RNA gene sequencing was performed on abscess samples. Polymerase chain reaction (PCR) and reverse-transcription PCR (RT-PCR) was used to validate the expression difference of T6SS hallmark genes. In vitro and in vivo experiments were performed to identify the pathogenic feature of T6SS. RESULTS: PICRUSt2 predicted that the T6SS-related genes were notably enriched in the IKPLA group. PCR detection of T6SS hallmark genes (hcp, vgrG, and icmF) showed that 197 (81.1%) were T6SS-positive strains. The T6SS-positive strain detection rate in the IKPLA group was higher than in the KPLA group (97.1% vs 78.4%; P < .05). RT-PCR showed that the hcp expression level was markedly increased in IKPLA isolates (P < .05). The T6SS-positive isolates showed higher survival against serum and neutrophil killing (all P < .05). The T6SS-positive K pneumoniae-infected mice had a shorter survival time, higher mortality, and an increased interleukin 6 expression in the liver and lungs (all P < .05). CONCLUSIONS: T6SS is an essential virulence factor for K pneumoniae and contributes to IKPLA.


Assuntos
Infecções por Klebsiella , Abscesso Hepático , Sistemas de Secreção Tipo VI , Animais , Camundongos , Sistemas de Secreção Tipo VI/genética , Sistemas de Secreção Tipo VI/metabolismo , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
18.
Microorganisms ; 11(4)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37110394

RESUMO

Nine novel bacterial strains were isolated from the feces of cats and sheep in 2019 and 2020 in Beijing, China. Cells were 1-3 µm long and ≤0.5 µm wide, Gram-stain negative, microaerobic, motile, oxidase positive, and urease negative. Phylogenetic analyses based on 16S rRNA gene sequences indicated that these nine isolates belong to the genus Campylobacter but formed two robust clades that were clearly separate from the currently recognized species and, respectively, isolated from the cat and sheep. Both these strains shared low 16S rRNA gene sequence similarity, dDDH relatedness, and ANI values with their closest species C. upsaliensis CCUG 14913T and C. lanienae NCTC 13004T, and against each other, which are below the cut-off values generally recognized for isolates of the same species. The genomic DNA G + C contents of type strains XJK22-1T and SYS25-1T were 34.99 mol% and 32.43 mol%, respectively. Electron microscopy showed that these cells were spiral shaped, with bipolar single flagella. Based on results from genotypic, phenotypic, phylogenetic, and phylogenomic analyses, these nine strains represent two novel species within the genus Campylobacter, for which the names Campylobacter felis sp. nov. (Type strain XJK22-1T = GDMCC 1.3684T = JCM 35847T) and Campylobacter ovis sp. nov. (Type strain SYS25-1T = GDMCC 1.3685T) are proposed.

19.
Animals (Basel) ; 13(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37106841

RESUMO

Climate change-induced food shortages pose major threats to wildlife conservation, and the exclusive reliance of giant pandas on bamboo makes them particularly vulnerable. The aim of this study was to provide insight into the reasons for the foraging strategies of giant pandas to selectively forage for different bamboo parts (bamboo shoot, culm, and leaf) during different seasons. This study used a metabolomic approach to analyze the fecal metabolites of giant pandas and conducted a correlation analysis with their gut microbiota. The results indicate that the fecal metabolites of giant pandas differ significantly depending on the bamboo parts they forage on, with higher sugar content observed when they consume bamboo culm with high fiber content. By functional annotation, culm group metabolites were enriched in the galactose metabolic pathway, while shoot group metabolites were enriched in the phenylalanine, tyrosine and tryptophan biosynthesis pathways. Moreover, Streptococcus showed a significant positive correlation with glucose and acetic acid content. Therefore, the foraging strategy of giant pandas is based on the ability to utilize the nutrient content of different bamboo parts. Captive feeding and habitat construction should enrich bamboo species to allow them to express their natural foraging strategies and improve their welfare and reproductive status.

20.
J Control Release ; 358: 190-203, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37116543

RESUMO

At present, the most widely used aluminum adjuvants have poor ability to induce effective Th1 type immune responses. Existing evidence suggests that manganese is a potential metal adjuvant by activating cyclic guanosine phospho-adenosine synthase (cGAS)-interferon gene stimulator protein (STING) signaling pathway to enhance humoral and cellular immune response. Hence, the effective modulation of metal components is expected to be a new strategy to improve the efficiency of vaccine immunization. Here, we constructed a manganese and aluminum dual-adjuvant antigen co-delivery system (MnO2-Al-OVA) to enhance the immune responses of subunit vaccines. Namely, the aluminum hydroxide was first fused on the surface of the pre-prepared MnO2 nanoparticles, which were synthesized by a simple redox reaction with potassium permanganate (KMnO4) and oleic acid (OA). The engineered MnO2-Al-OVA could remarkably promote cellular internalization and maturation of dendritic cells. After subcutaneous vaccination, MnO2-Al-OVA rapidly migrated into the lymph nodes (LNs) and efficiently activate the cGAS-STING pathway, greatly induced humoral and cellular immune responses. Of note, our findings underscore the importance of coordination manganese adjuvants in vaccine design by promoting the activation of the cGAS-STING-IFN-I pathway. With a good safety profile and facile preparation process, this dual-adjuvant antigen co-delivery nanovaccine has great potential for clinical translation prospects.


Assuntos
Alumínio , Nanopartículas , Alumínio/farmacologia , Manganês , Compostos de Manganês/farmacologia , Óxidos , Adjuvantes Imunológicos , Imunidade Celular , Antígenos , Vacinas de Subunidades Antigênicas , Nucleotidiltransferases/farmacologia , Células Dendríticas , Imunidade Humoral
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