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1.
Brief Bioinform ; 25(5)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39082651

RESUMO

Constructing accurate gene regulatory network s (GRNs), which reflect the dynamic governing process between genes, is critical to understanding the diverse cellular process and unveiling the complexities in biological systems. With the development of computer sciences, computational-based approaches have been applied to the GRNs inference task. However, current methodologies face challenges in effectively utilizing existing topological information and prior knowledge of gene regulatory relationships, hindering the comprehensive understanding and accurate reconstruction of GRNs. In response, we propose a novel graph neural network (GNN)-based Multi-Task Learning framework for GRN reconstruction, namely MTLGRN. Specifically, we first encode the gene promoter sequences and the gene biological features and concatenate the corresponding feature representations. Then, we construct a multi-task learning framework including GRN reconstruction, Gene knockout predict, and Gene expression matrix reconstruction. With joint training, MTLGRN can optimize the gene latent representations by integrating gene knockout information, promoter characteristics, and other biological attributes. Extensive experimental results demonstrate superior performance compared with state-of-the-art baselines on the GRN reconstruction task, efficiently leveraging biological knowledge and comprehensively understanding the gene regulatory relationships. MTLGRN also pioneered attempts to simulate gene knockouts on bulk data by incorporating gene knockout information.


Assuntos
Biologia Computacional , Redes Reguladoras de Genes , Biologia Computacional/métodos , Técnicas de Inativação de Genes , Redes Neurais de Computação , Humanos , Regiões Promotoras Genéticas , Algoritmos
2.
Brief Bioinform ; 24(6)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37742052

RESUMO

Drug-drug interaction (DDI) prediction can discover potential risks of drug combinations in advance by detecting drug pairs that are likely to interact with each other, sparking an increasing demand for computational methods of DDI prediction. However, existing computational DDI methods mostly rely on the single-view paradigm, failing to handle the complex features and intricate patterns of DDIs due to the limited expressiveness of the single view. To this end, we propose a Hierarchical Triple-view Contrastive Learning framework for Drug-Drug Interaction prediction (HTCL-DDI), leveraging the molecular, structural and semantic views to model the complicated information involved in DDI prediction. To aggregate the intra-molecular compositional and structural information, we present a dual attention-aware network in the molecular view. Based on the molecular view, to further capture inter-molecular information, we utilize the one-hop neighboring information and high-order semantic relations in the structural view and semantic view, respectively. Then, we introduce contrastive learning to enhance drug representation learning from multifaceted aspects and improve the robustness of HTCL-DDI. Finally, we conduct extensive experiments on three real-world datasets. All the experimental results show the significant improvement of HTCL-DDI over the state-of-the-art methods, which also demonstrates that HTCL-DDI opens new avenues for ensuring medication safety and identifying synergistic drug combinations.


Assuntos
Aprendizado Profundo , Interações Medicamentosas , Semântica
3.
Brief Bioinform ; 24(2)2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36892155

RESUMO

Drug-target interaction (DTI) prediction can identify novel ligands for specific protein targets, and facilitate the rapid screening of effective new drug candidates to speed up the drug discovery process. However, the current methods are not sensitive enough to complex topological structures, and complicated relations between multiple node types are not fully captured yet. To address the above challenges, we construct a metapath-based heterogeneous bioinformatics network, and then propose a DTI prediction method with metapath-based hierarchical transformer and attention network for drug-target interaction prediction (MHTAN-DTI), applying metapath instance-level transformer, single-semantic attention and multi-semantic attention to generate low-dimensional vector representations of drugs and proteins. Metapath instance-level transformer performs internal aggregation on the metapath instances, and models global context information to capture long-range dependencies. Single-semantic attention learns the semantics of a certain metapath type, introduces the central node weight and assigns different weights to different metapath instances to obtain the semantic-specific node embedding. Multi-semantic attention captures the importance of different metapath types and performs weighted fusion to attain the final node embedding. The hierarchical transformer and attention network weakens the influence of noise data on the DTI prediction results, and enhances the robustness and generalization ability of MHTAN-DTI. Compared with the state-of-the-art DTI prediction methods, MHTAN-DTI achieves significant performance improvements. In addition, we also conduct sufficient ablation studies and visualize the experimental results. All the results demonstrate that MHTAN-DTI can offer a powerful and interpretable tool for integrating heterogeneous information to predict DTIs and provide new insights into drug discovery.


Assuntos
Desenvolvimento de Medicamentos , Descoberta de Drogas , Simulação por Computador , Descoberta de Drogas/métodos , Proteínas/química , Aprendizagem
4.
FASEB J ; 38(16): e23882, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39143727

RESUMO

Phillygenin (PHI) is an active ingredient derived from the leaf of Forsythia suspensa that has been found to alleviate inflammation and peroxidation response. Avian infectious bronchitis (IB) is a major threat to poultry industry viral respiratory tract disease that infected with infectious bronchitis virus (IBV). This study investigated the protection of PHI to CEK cell and broiler's tracheal injury triggered by avian infectious bronchitis virus (IBV). The results showed that IBV infection did not cause serious clinical symptoms and slowing-body weight in PHI-treated broilers. The expression of virus loads, pro-inflammation factors (IL-6, TNF-α, and IL-1ß) in CEK cell, and tracheas were decreased compared to the IBV group, exhibiting its potent anti-inflammation. Mechanistically, the study demonstrated that the inhibition of TLR7/MyD88/NF-κB pathway was mainly involved in the protection effect of PHI to inflammation injury. Interestingly, a higher abundance of Firmicutes and Lactobacillus in respiratory tract was observed in PHI-treated broilers than in the IBV group. Significant differences were observed between the IBV group and PHI-treated group in the Ferroptosis, Tryptophan metabolism, and Glutathione metabolism pathways. PHI exhibited potent protection effect on IBV infection and alleviated inflammation injury, mainly through inhibiting TLR7/MyD88/NF-κB pathway. The study encourages further development of PHI, paving the way to its clinical use as a new candidate drug to relieve IBV-induced respiratory symptoms.


Assuntos
Galinhas , Infecções por Coronavirus , Vírus da Bronquite Infecciosa , Fator 88 de Diferenciação Mieloide , NF-kappa B , Doenças das Aves Domésticas , Receptor 7 Toll-Like , Animais , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/metabolismo , Receptor 7 Toll-Like/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/veterinária , Microbiota/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
5.
Mol Biol Rep ; 51(1): 84, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38183522

RESUMO

PURPOSE: Investigate the role of COX signaling in activating the PGE2-EP2 pathway. METHODS: Utilized a marine Mycobacterium infection model in zebrafish. Marine mycobacteria were stained with fluorescein isothiocyanate. The COX inhibitor indomethacin, EP2 receptor inhibitor AH6809, EP4 receptor inhibitor AH23848 and clodronate Liposomes were used to investigate the role of COX, EP2, EP4 and macrophage whether participating in combat marine mycobacterial infection. The expression level of the target gene was detected using real-time fluorescence quantitative PCR instrument. RESULTS: The findings revealed that larvae exposed to the COX inhibitor indomethacin or the EP2 receptor inhibitor AH6809 demonstrated a significantly higher mortality rate due to marine mycobacterium infection than those in the control group. Administration of exogenous prostaglandin E2 (PGE2) rescued the survival of zebrafish infected with marine mycobacteria and treated with indomethacin. Additionally, a significant reduction in survival rate was noted in macrophage-depleted zebrafish infected with marine mycobacteria. CONCLUSION: The host may combat marine mycobacterium infection via COX signaling, which activates the PGE2-EP2 pathway and mediates macrophage resistance.


Assuntos
Infecções por Mycobacterium , Mycobacterium marinum , Animais , Dinoprostona , Prostaglandina-Endoperóxido Sintases , Peixe-Zebra , Indometacina/farmacologia
6.
BMC Vet Res ; 20(1): 19, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195531

RESUMO

BACKGROUND: The present study aimed to investigate the prevalence and molecular characterization of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli (E. coli) isolated from dairy cattle with endometritis in China. The prevalence of ESBL-producing E. coli in sample was detected using ChromID ESBL agar, and genotyping of the ESBL producers was performed by PCR and DNA sequencing. RESULTS: The results revealed that the proportion of positive pathogens tested was 69.76% (180/258) in samples obtained from cows diagnosed with clinical endometritis, with E. coli accounting for 170 out of the 180 positive samples. The infection rate of isolated E. coli was 39.14% (101/258), and co-infections with other pathogens were prevalent. Furthermore, among the 158 E. coli isolates, 50 strains were identified as ESBL producers, with TEM and CTX-M prevalence rates at 78.00% and 32.00%, respectively. Drug sensitivity experiments indicated that 50 isolates of ESBL- producing E. coli were multidrug resistance (MDR), with 48.0% of them exhibiting positive results for both the class 1 integron gene and five gene cassettes associated with resistance to trimethoprim (dfr1 and dfrA17) and aminoglycosides (aadA1, aadA5, and dfrA1), respectively. CONCLUSION: This investigation demonstrated a substantial prevalence and heightened level of antimicrobial resistance among ESBL-producing E. coli isolates derived from dairy cattle infected with endometritis in China.


Assuntos
Doenças dos Bovinos , Endometrite , Feminino , Animais , Bovinos , Endometrite/epidemiologia , Endometrite/veterinária , Escherichia coli/genética , Prevalência , China/epidemiologia , beta-Lactamases/genética , Doenças dos Bovinos/epidemiologia
7.
Int J Mol Sci ; 25(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38396786

RESUMO

An increasing amount of evidence indicates that Baicalin (Bai, a natural glycosyloxyflavone compound) exhibits an antiviral effect against avian viruses. However, it remains unclear if the antiviral effect of Bai against infectious bronchitis virus (IBV) is exerted indirectly by modulating respiratory tract microbiota and/or their metabolites. In this study, we investigated the protection efficacy of Bai in protecting cell cultures and broilers from IBV infection and assessed modulation of respiratory tract microbiota and metabolites during infection. Bai was administered orally to broilers by being mixed in with drinking water for seven days. Ultimately, broilers were challenged with live IBV. The results showed that Bai treatment reduced respiratory tract symptoms, improved weight gain, slowed histopathological damage, reduced virus loads and decreased pro-inflammation cytokines production. Western blot analysis demonstrated that Bai treatment significantly inhibited Toll-like receptor 7 (TLR7), myeloid differentiation factor 88 (MyD88) and nuclear factor kappa-B (NF-κB) expression both in cell culture and cells of the trachea. Bai treatment reversed respiratory tract microbiota dysbiosis, as shown by 16S rDNA sequencing in the group of broilers inoculated with IBV. Indeed, we observed a decrease in Proteobacteria abundance and an increase in Firmicutes abundance. Metabolomics results suggest that the pentose phosphate pathway, amino acid and nicotinamide metabolism are linked to the protection conferred by Bai against IBV infection. In conclusion, these results indicated that further assessment of anti-IBV strategies based on Bai would likely result in the development of antiviral molecule(s) which can be administered by being mixed with feed or water.


Assuntos
Infecções por Coronavirus , Flavonoides , Gammacoronavirus , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Animais , Galinhas , Traqueia , Antivirais/farmacologia , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/microbiologia
8.
Angew Chem Int Ed Engl ; 63(20): e202402829, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38380830

RESUMO

Post-synthetic modification plays a crucial role in precisely adjusting the structure and functions of advanced materials. Herein, we report the self-assembly of a tubular heterometallic Pd3Cu6L16 capsule that incorporates Pd(II) and CuL1 metalloligands. This capsule undergoes further modification with two tridentate anionic ligands (L2) to afford a bicapped Pd3Cu6L16L22 capsule with an Edshammer polyhedral structure. By employing transition metal ions, acid, and oxidation agents, the bicapped capsule can be converted into an uncapped one. This uncapped form can then revert back to the bicapped structure on the addition of Br- ions and a base. Interestingly, introducing Ag+ ions leads to the removal of one L2 ligand from the bicapped capsule, yielding a mono-capped Pd3Cu6L16L2 structure. Furthermore, the size of the anions critically influences the precise control over the post-synthetic modifications of the capsules. It was demonstrated that these capsules selectively encapsulate tetrahedral anions, offering a novel approach for the design of intelligent molecular delivery systems.

9.
BMC Musculoskelet Disord ; 24(1): 728, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37700293

RESUMO

BACKGROUND: To investigate the risk factors for new vertebral compression fractures (NVCFs) after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCFs) and to create a nomogram to predict the occurrence of new postoperative fractures. METHODS: This was a retrospective analysis of the clinical data of 529 OVCF patients who received PKP treatment in our hospital from June 2017 to June 2020. Based on whether there were new fractures within 2 years after surgery, the patients were divided into a new fracture group and a nonnew fracture group. Univariate and multivariate analyses were used to determine the risk factors for the occurrence of NVCFs after surgery. The data were randomly divided into a training set (75%) and a testing set (25%). Nomograms predicting the risk of NVCF occurrence were created based on the results of the multivariate analysis, and performance was evaluated using receiver operating characteristic curves (ROCs), calibration curves, and decision curve analyses (DCAs). A web calculator was created to give clinicians a more convenient interactive experience. RESULTS: A total of 56 patients (10.6%) had NVCFs after surgery. The univariate analysis showed significant differences in sex and the incidences of cerebrovascular disease, a positive fracture history, and bone cement intervertebral leakage between the two groups (P < 0.05). The multivariate analysis showed that sex [OR = 2.621, 95% CI (1.030-6.673), P = 0.043], cerebrovascular disease [OR = 28.522, 95% CI (8.749-92.989), P = 0.000], fracture history [OR = 12.298, 95% CI (6.250-24.199), P = 0.000], and bone cement intervertebral leakage [OR = 2.501, 95% CI (1.029-6.082), P = 0.043] were independent risk factors that were positively associated with the occurrence of NVCFs. The AUCs of the model were 0.795 (95% CI: 0.716-0.874) and 0.861 (95% CI: 0.749-0.974) in the training and testing sets, respectively, and the calibration curves showed high agreement between the predicted and actual states. The areas under the decision curve were 0.021 and 0.036, respectively. CONCLUSION: Female sex, cerebrovascular disease, fracture history and bone cement intervertebral leakage are risk factors for NVCF after PKP. Based on this, a highly accurate nomogram was developed, and a webpage calculator ( https://new-fracture.shinyapps.io/DynNomapp/ ) was created.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas da Coluna Vertebral , Idoso , Humanos , Feminino , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/epidemiologia , Fraturas por Compressão/etiologia , Nomogramas , Cimentos Ósseos/efeitos adversos , Cifoplastia/efeitos adversos , Estudos Retrospectivos
10.
Molecules ; 28(13)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37446922

RESUMO

Benefiting from a high quantum efficiency, low thermal emittance, and large absorption coefficient, InxGa1-xAs is an excellent group III-V compound for negative electron affinity (NEA) photocathodes. As the emission layer, InxGa1-xAs, where x = 0.15, has the optimal performance for detection in the near-infrared (NIR) region. Herein, an NEA In0.15Ga0.85As photocathode with Al0.63Ga0.37As as the buffer layer is designed in the form of a transmission mode module. The electronic band structures and optical properties of In0.15Ga0.85As and Al0.63Ga0.37As are calculated based on density functional theory. The time response characteristics of the In0.15Ga0.85As photocathode have been fully investigated by changing the photoelectron diffusion coefficient, the interface recombination velocity, and the thickness of the emission layer. Our results demonstrate that the response time of the In0.15Ga0.85As photocathode can be reduced to 6.1 ps with an incident wavelength of 1064 nm. The quantum efficiency of the In0.15Ga0.85As photocathode is simulated by taking into account multilayer optical thin film theory. The results indicate that a high quantum efficiency can be obtained by parameter optimization of the emission layer. This paper provides significant theoretical support for the applications of semiconductor photocathodes in the near-infrared region, especially for the study of ultrafast responses in the photoemission process.


Assuntos
Eletrônica , Semicondutores , Tempo de Reação , Modelos Teóricos
11.
Angew Chem Int Ed Engl ; 62(50): e202315020, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37884445

RESUMO

The development of energy-saving technology for the efficient separation of olefin and paraffin is highly important for the chemical industry. Herein, we report a self-assembled Fe4 L6 capsule containing a hydrophobic cavity, which can be used to encapsulate and separate propylene/propane. The successful encapsulation of propylene and propane by the Fe4 L6 cage in a water solution was documented by NMR spectroscopy. The binding constants K for the Fe4 L6 cage toward propylene and propane were determined to be (5.0±0.1)×103  M-1 and (2.1±0.7)×104  M-1 in D2 O at 25 °C, respectively. Experiments and theoretical studies revealed that the cage exhibited multiple weak interactions with propylene and propane. The polymer-grade propylene (>99.5 %) can be obtained from a mixture of propylene and propane by using the Fe4 L6 cage as a separation material in a U-shaped glass tube. This work provides a new strategy for the separation of olefin/paraffin.

12.
Inorg Chem ; 61(13): 5196-5200, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35324197

RESUMO

Herein we report a discrete heterometallic Pd4Cu8L8 cage with a tubular structure, which was synthesized by the assembly of copper metalloligands and PdII ions in a stepwise manner. The Pd4Cu8L8 cage has been unequivocally characterized by single-crystal X-ray diffraction, electrospray ionization-mass spectroscopy, and energy dispersive spectroscopy. The cage showed excellent catalytic activity in the epoxidation of styrene and its derivatives under conditions without using additional solvent, providing potential material for catalyzing the oxidation reactions.

13.
BMC Infect Dis ; 22(1): 742, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123623

RESUMO

Coronavirus disease 2019 (COVID-19) continues to constitute an international public health emergency. Vaccination is a prospective approach to control this pandemic. However, apprehension about the safety of vaccines is a major obstacle to vaccination. Amongst health professionals, one evident concern is the risk of antibody-dependent enhancement (ADE), which may increase the severity of COVID-19. To explore whether ADE occurs in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and increase confidence in the safety of vaccination, we conducted a meta-analysis to investigate the relationship between post-immune infection and disease severity from a population perspective. Databases, including PubMed, EMBASE, Chinese National Knowledge Infrastructure, SinoMed, Scopus, Science Direct, and Cochrane Library, were searched for articles on SARS-CoV-2 reinfection published until 25 October 2021. The papers were reviewed for methodological quality, and a random effects model was used to analyse the results. Heterogeneity was assessed using the I2 statistic. Publication bias was evaluated using a funnel plot and Egger's test. Eleven studies were included in the final meta-analysis. The pooled results indicated that initial infection and vaccination were protective factors against severe COVID-19 during post-immune infection (OR = 0.55, 95%CI = 0.31-0.98). A subgroup (post-immune infection after natural infection or vaccination) analysis showed similar results. Primary SARS-CoV-2 infection and vaccination provide adequate protection against severe clinical symptoms after post-immune infection. This finding demonstrates that SARS-CoV-2 may not trigger ADE at the population level.


Assuntos
COVID-19 , Vacinas , Anticorpos Antivirais , Anticorpos Facilitadores , COVID-19/prevenção & controle , Humanos , SARS-CoV-2 , Vacinação
14.
Avian Pathol ; 51(6): 574-589, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35917182

RESUMO

Baicalin, a flavonoid compound extracted from the dry root of Scutellaria baicalensis Georgi, has been shown to have anti-inflammation, anti-viral, anti-bacterial, and immunomodulatory activity. However, the effect of baicalin against avian infectious bronchitis virus (IBV) remains unknown. The purpose of this study was to investigate the anti-IBV activity and underlying mechanism of baicalin in vitro. The results showed that baicalin has a direct virucidal effect but no prophylactic effect on IBV infection. The mRNA and protein of IBV N were decreased significantly when IBV-infected cells were treated with baicalin during the multiple stages of the virus replication cycle, including viral adsorption, invasion, internalization, and release. Stress granule (SG) formation resulted from the increase of G3BP1 and the phosphorylation of the PKR/eIF2α due to the treatment of IBV-infected cells with baicalin. The inhibitory activity of baicalin on IBV replication was increased when G3BP1 expression was inhibited, and the down-regulation of G3BP1 expression occurred when the expression of PKR and eIF2α was inhibited. These findings revealed that baicalin activates phosphorylation of the PKR/eIF2α pathway and induces SG formation by targeting G3BP1, initiating the antiviral response to suppress IBV replication in Vero cells. The results suggest that baicalin is a promising candidate drug to treat or prevent IBV infection.RESEARCH HIGHLIGHTS Baicalin inhibits IBV replication by reducing IBV N protein and mRNA.Baicalin disturbs multiple stages of the IBV life cycle.Baicalin activates PKR/eIF2α pathway and induces stress granule formation to exert anti-IBV response.


Assuntos
Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Chlorocebus aethiops , Animais , Antivirais/farmacologia , Células Vero , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , DNA Helicases/metabolismo , DNA Helicases/farmacologia , Proteínas de Ligação a Poli-ADP-Ribose , RNA Helicases/genética , RNA Helicases/metabolismo , RNA Helicases/farmacologia , Doenças das Aves Domésticas/tratamento farmacológico , Flavonoides/farmacologia , RNA Mensageiro , Replicação Viral
15.
BMC Microbiol ; 21(1): 281, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34657588

RESUMO

BACKGROUND: Bloodstream infection (BSI) caused by Staphylococcus aureus (S. aureus) can be life-threatening and pose a great challenge to infection control and clinical treatment. However, little information exists regarding the characterization of S. aureus in BSI patients in Shandong, China. To identify the clonality, virulence genes, and antibiotic resistance of S. aureus in blood, a total of 101 nonrepetitive blood isolates were collected. The antibiotic resistance phenotypes were determined, and virulence genes were analyzed with polymerase chain reaction (PCR). Finally, the genetic relatedness was investigated with Staphylococcus chromosomal cassette mec (SCCmec) typing for methicillin-resistant S. aureus (MRSA) isolates, Staphylococcal protein A (spa), and multilocus sequence typing (MLST) for all of 101 isolates. RESULTS: Of the 101 S. aureus isolates, 24 MRSA isolates and 77 methicillin-susceptible S. aureus (MSSA) isolates were identified. Overall, MRSA isolates had higher resistance rates than MSSA isolates when exposed to any of the 15 antibiotics tested in this study except for trimethoprim/sulfamethoxazole. Among the 17 virulence genes tested in this study, hla, hld, and hlg could be detected in all isolates. MRSA isolates were more likely to carry seb and hlb genes, while MSSA isolates were more likely to carry seg and sei genes. Thirty-five sequence types (STs) and 49 spa types were identified, of which ST59-t437 and ST398-t571 were the most abundant. These two genotypes were also the most abundant ST-spa types in MRSA and MSSA isolates, but their abundances shifted over time, with ST398-t571 being the predominant genotype from 2016 to 2017, and ST59-t437 from 2018 to 2020. Besides, all the ST59-t437 isolates harbored hlgb gene, whereas most (88.9%) ST398-t571 did not. In addition, twenty-four MRSA isolates were subject to SCCmec typing. SCCmec IVa was the most prevalent SCCmec type, and all the ST59-t437 MRSA isolates were SCCmec IVa. We also observed 15 new STs, and some of them were MRSA. CONCLUSION: These findings provide additional observations and epidemiological data for blood S. aureus isolates, which can improve future infection-control measures and aid in potential clinical treatments in hospitals and other clinical settings.


Assuntos
Bacteriemia/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Antibacterianos/farmacologia , China/epidemiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Genes Bacterianos/genética , Genótipo , Hospitais , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Proteína Estafilocócica A/genética , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Virulência/genética
16.
Inorg Chem ; 60(2): 565-569, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33405909

RESUMO

A unique metal-organic framework (MOF) with tetrazole-padded helical channels has been successfully synthesized in one pot from iron(II) trifluoromethanesulfonate, 4-formylimidazole, hydrazine, and sodium azide under solvothermal conditions and features a rare unh topology and porous structure for gas adsorption. Transformations of condensation, cycloaddition, and coordination occurred during the synthetic process, in which a 1,5-disubstituted tetrazole ligand was formed in situ.

17.
Inorg Chem ; 60(14): 10380-10386, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34171190

RESUMO

Water oxidation to molecular oxygen is indispensable but a challenge for splitting H2O. In this work, a series of Co-based metal-organic cages (MOCs) for photoinduced water oxidation were prepared. MOC-1 with both bis(µ-oxo) bridged dicobalt and Co-O (O from H2O) displays catalytic activity with an initial oxygen evolution rate of 80.4 mmol/g/h and a TOF of 7.49 × 10-3 s-1 in 10 min. In contrast, MOC-2 containing only Co-O (O from H2O) in the structure results in a lower oxygen evolution rate (40.8 mmol/g/h, 4.78 × 10-3 s-1), while the amount of oxygen evolved from the solution of MOC-4 without both active sites is undetectable. Isotope experiments with or without H218O as the reactant successfully demonstrate that the molecular oxygen was produced from water oxidation. Photophysical and electrochemical studies reveal that photoinduced water oxidation initializes via electron transfer from the excited [Ru(bpy)3]2+* to Na2S2O8, and then, the cobalt active sites further donate electrons to the oxidized [Ru(bpy)3]3+ to drive water oxidation. This proof-of-concept study indicates that MOCs can work as potential efficient catalysts for photoinduced water oxidation.

18.
Int J Med Sci ; 18(9): 1935-1945, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33850462

RESUMO

The prevalence of drug-resistant Mycobacterium tuberculosis (Mtb) strains makes disease control more complicated, which is the main cause of death in tuberculosis (TB) patients. Early detection and timely standard treatment are the key to current prevention and control of drug-resistant TB. In recent years, despite the continuous advancement in drug-resistant TB diagnostic technology, the needs for clinical rapid and accurate diagnosis are still not fully met. With the development of sequencing technology, the research of human microecology has been intensified. This study aims to use 16 rRNA sequencing technology to detect and analyze upper respiratory flora of TB patients with anti-TB drug sensitivity (DS, n = 55), monoresistance isoniazide (MR-INH, n = 33), monoresistance rifampin (MR-RFP, n = 12), multidrug resistance (MDR, n = 26) and polyresistance (PR, n = 39) in southern China. Potential microbial diagnostic markers for different types of TB drug resistance are searched by screening differential flora, which provides certain guiding significance for drug resistance diagnosis and clinical drug use of TB. The results showed that the pulmonary microenvironment of TB patients was more susceptible to infection by external pathogens, and the infection of different drug-resistant Mtb leads to changes in different flora. Importantly, seven novel microorganisms (Leptotrichia, Granulicatella, Campylobacter, Delfitia, Kingella, Chlamydophila, Bordetella) were identified by 16S rRNA sequencing as diagnostic markers for different drug resistance types of TB. Leptotrichia, Granulicatella, Campylobacter were potential diagnostic marker for TB patients with INH single-resistance. Delftia was a potential diagnostic marker for TB patients with RFP single drug-resistance. Kingella and Chlamydophila can be used as diagnostic markers for TB patients with PR. Bordetella can be used as a potential diagnostic marker for identification of TB patients with MDR.


Assuntos
Antituberculosos/farmacologia , Microbiota , Escarro/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Pulmonar/diagnóstico , Adolescente , Adulto , Idoso , Antituberculosos/uso terapêutico , DNA Bacteriano/isolamento & purificação , Feminino , Humanos , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Rifampina/farmacologia , Rifampina/uso terapêutico , Sensibilidade e Especificidade , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico , Adulto Jovem
19.
Sensors (Basel) ; 21(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671554

RESUMO

This paper considers the two-dimensional (2D) anchorless localization problem for sensor networks in global positioning system (GPS)-denied environments. We present an efficient method, based on the multidimensional scaling (MDS) algorithm, in order to estimate the positions of the nodes in the network using measurements of the inter-node distances. The proposed method takes advantage of the mobility of the nodes to address the location ambiguity problem, i.e., rotation and flip ambiguity, which arises in the anchorless MDS algorithm. Knowledge of the displacement of the moving node is used to produce an analytical solution for the noise-free case. Subsequently, a least squares estimator is presented for the noisy scenario and the associated closed-form solution derived. The simulations show that the proposed algorithm accurately and efficiently estimates the locations of nodes, outperforming alternative methods.

20.
Inorg Chem ; 59(23): 17374-17378, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33170005

RESUMO

A triangular prismatic metal-organic cage based on mixed valence copper ions has been designed and synthesized by using metallocycle panels and pillar ligands. The triangular prism will be quickly transformed to a 10-nuclear cage upon an external chemical stimulus, which features a bicapped square antiprism structure. This prismatic cage can act as a catalyst for oxidation of aromatic alcohols to their corresponding aromatic aldehydes with high yields at room temperature under O2 atmosphere.

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