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1.
J Am Chem Soc ; 146(10): 6744-6752, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38422617

RESUMO

Zinc-iodine batteries are one of the most intriguing types of batteries that offer high energy density and low toxicity. However, the low intrinsic conductivity of iodine, together with high polyiodide solubility in aqueous electrolytes limits the development of high-areal-capacity zinc-iodine batteries with high stability, especially at low current densities. Herein, we proposed a hydrophobic polyiodide ionic liquid as a zinc-ion battery cathode, which successfully activates the iodine redox process by offering 4 orders of magnitude higher intrinsic electrical conductivity and remarkably lower solubility that suppressed the polyiodide shuttle in a dual-plating zinc-iodine cell. By the molecular engineering of the chemical structure of the polyiodide ionic liquid, the electronic conductivity can reach 3.4 × 10-3 S cm-1 with a high Coulombic efficiency of 98.2%. The areal capacity of the zinc-iodine battery can achieve 5.04 mAh cm-2 and stably operate at 3.12 mAh cm-2 for over 990 h. Besides, a laser-scribing designed flexible dual-plating-type microbattery based on a polyiodide ionic liquid cathode also exhibits stable cycling in both a single cell and 4 × 4 integrated cell, which can operate with the polarity-switching model with high stability.

2.
J Antimicrob Chemother ; 79(6): 1309-1312, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38564262

RESUMO

OBJECTIVES: To evaluate the performance of an in-house developed disk diffusion method for aztreonam in combination with avibactam against Enterobacteriales. METHODS: The in vitro antibacterial activity of aztreonam with avibactam against 204 carbapenemase-producing Enterobacteriales was determined by a disk diffusion method, with a broth microdilution method as a reference. RESULTS: The optimal S/R breakpoints for disk diffusion tests of 30/20 and 10/4 µg disks, calculated by the dBETs software using the model-based approaches, were ≥22/≤21 and ≥12/≤11 mm, respectively. On the basis of the estimated breakpoints, the CAs for disk diffusion tests of 30/20 and 10/4 µg aztreonam/avibactam disks were both 98.0%, with 0.5% major error and 37.5% very major error. CONCLUSIONS: The home-made disk diffusion method is an economical and practical method for clinical microbiology laboratories to determine the antibacterial susceptibility of aztreonam with avibactam against Enterobacteriales.


Assuntos
Antibacterianos , Compostos Azabicíclicos , Aztreonam , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Enterobacteriaceae , Aztreonam/farmacologia , Compostos Azabicíclicos/farmacologia , Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/métodos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/normas , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Humanos
3.
Angew Chem Int Ed Engl ; : e202407067, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771481

RESUMO

The instability of the solid electrolyte interface (SEI) is a critical challenge for the zinc metal anodes, leading to an erratic electrode/electrolyte interface and hydrogen evolution reaction (HER), ultimately resulting in anode failure. This study uncovers that the fluorine species dissolution is the root cause of SEI instability. To effectively suppress the F- dissolution, an introduction of low-polarity molecule, 1,4-thioxane (TX), is proposed, which reinforces the stability of the fluorine-rich SEI. Moreover, the TX molecule has a strong affinity for coordinating with Zn2+ and adsorbing at the electrode/electrolyte interface, thereby diminishing the activity of local water and consequently impeding SEI dissolution. The robust fluorine-rich SEI layer promotes the high durability of the zinc anode in repeated plating/stripping cycles, while concurrently suppressing HER and enhancing Coulombic efficiency. Furthermore, the Zn||KVOH full cell exhibits excellent capacity retention, averaging 6.8 mAh cm-2 with 98% retention after 400 cycles, even at high loading with a lean electrolyte. This work offers a novel perspective on SEI dissolution as a key factor in anode failure, providing valuable insights for the electrolyte design in energy storage devices.

4.
Hematol Oncol ; 41(3): 396-406, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36516297

RESUMO

Extranodal natural killer/T cell lymphoma (ENKTL) patients typically face a grim prognosis after relapse or progression following asparaginase-based chemotherapy. Currently, programmed cell death protein-1 (PD-1) immune checkpoint blockade has shown promising efficacy as an optimal regimen for relapsed or refractory ENKTL (rrENKTL) patients. This study retrospectively investigated the efficacy, safety, and factors influencing the survival of 26 rrENKTL patients who underwent monoclonal antibody treatment using PD-1 (Sintilimab or Camrelizumab) alone or combined with chemotherapy from January 2018 to February 2022. The disease control rate was 73.1%, and the objective response rate was 50.0%. 15.4% of the patients achieved complete remission, and 34.6% achieved partial remission (PR). After a median follow-up of 12 (range 3-47) months, the median progression-free survival (PFS) and overall survival (OS) were 6.5 and 13.3 months. The 1-year PFS and OS rate were 23.1% and 53.8%. 96.2% of patients experienced at least one adverse event and 26.9% experienced grade 1-2 immune-related adverse events. PD-1 inhibitor improved rrENKTL patient survival, and the AEs were controlled. We also observed that the prognostic index for NK cell lymphoma including Epstein-Barr virus (EBV) (PINK-E) and the nomogram-revised risk indexz for ENKTL patients could help identify a potentially unfavorable prognosis in this era of immunotherapy. More attention should be paid to the presence of EBV after anti-PD-1 immunotherapy, as it more accurately indicates a poor prognosis.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma Extranodal de Células T-NK , Humanos , Estudos Retrospectivos , Inibidores de Checkpoint Imunológico/efeitos adversos , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Linfoma Extranodal de Células T-NK/terapia , Herpesvirus Humano 4 , Recidiva Local de Neoplasia/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
5.
Plant J ; 106(2): 351-365, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33486798

RESUMO

Lotus plumule, the embryo of the seed of the sacred lotus (Nelumbo nucifera), contains a high accumulation of secondary metabolites including flavonoids and possesses important pharmaceutical value. Flavonoid C-glycosides, which accumulate exclusively in lotus plumule, have attracted considerable attention in recent decades due to their unique chemical structure and special bioactivities. As well as mono-C-glycosides, lotus plumule also accumulates various kinds of di-C-glycosides by mechanisms which are as yet unclear. In this study we identified two C-glycosyltransferase (CGT) genes by mining sacred lotus genome data and provide in vitro and in planta evidence that these two enzymes (NnCGT1 and NnCGT2, also designated as UGT708N1 and UGT708N2, respectively) exhibit CGT activity. Recombinant UGT708N1 and UGT708N2 can C-glycosylate 2-hydroxyflavanones and 2-hydroxynaringenin C-glucoside, forming flavone mono-C-glycosides and di-C-glycosides, respectively, after dehydration. In addition, the above reactions were successfully catalysed by cell-free extracts from tobacco leaves transiently expressing NnCGT1 or NnCGT2. Finally, enzyme assays using cell-free extracts of lotus plumule suggested that flavone di-C-glycosides (vicenin-1, vicenin-3, schaftoside and isoschaftoside) are biosynthesized through sequentially C-glucosylating and C-arabinosylating/C-xylosylating 2-hydroxynaringenin. Taken together, our results provide novel insights into the biosynthesis of flavonoid di-C-glycosides by proposing a new biosynthetic pathway for flavone C-glycosides in N. nucifera and identifying a novel uridine diphosphate-glycosyltransferase (UGT708N2) that specifically catalyses the second glycsosylation, C-arabinosylating and C-xylosylating 2-hydroxynaringenin C-glucoside.


Assuntos
Flavonoides/metabolismo , Glicosídeos/metabolismo , Nelumbo/metabolismo , Glicosilação , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Redes e Vias Metabólicas , Nelumbo/enzimologia , Nelumbo/genética , Filogenia , Plantas Geneticamente Modificadas , Nicotiana
6.
Gynecol Oncol ; 165(1): 105-113, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35151492

RESUMO

OBJECTIVE: Gastric-type cervical adenocarcinoma (GCA) is a rare and aggressive type of endocervical adenocarcinoma (ECA) with distinct histopathologic features and unfavorable treatment outcomes, but no genomic prognostic factor has been revealed. We aimed to systematically investigate the somatic alterations of GCA at genome-wide level and evaluate their prognostic value. METHODS: We performed whole-exome sequencing (WES) on 25 pairs of tumor and matched normal samples to characterize the genomic features of Chinese patients with GCA and investigated their relations to histopathological characterizations and prognosis. The prognostic value of the genomic alterations was evaluated in a total of 58 GCA patients. RESULTS: Mutations were commonly observed in reported GCA-related driver genes, including TP53 (32%), CDKN2A (20%), SKT11 (20%), BRCA2 (12%), SMAD4 (12%), and ERBB2 (12%). Recurrent novel trunk mutations were also observed in PBRM1 (12%), FRMPD4 (12%), and NOP2 (8%) with high variant allele frequency. Moreover, enrichment of the APOBEC signature was attributed to frequent gain of somatic copy number alteration (SCNA) of APOBEC3B (20%), which perfectly matched the nuclear-positive staining of APOBEC3B through immunohistochemistry. In contrast, APOBEC3B alteration was absent in patients with conventional type of ECA (N = 52). Notably, positive APOBEC3B was consistently enriched in patients with favorable prognosis in both the discovery cohort and an additional 33 GCA patients, thus indicating a significant association with lower relapse risk of GCA independent of cancer stage (P = 0.02). CONCLUSION: Our results can aid understanding of the molecular basis of GCA in the Chinese population by providing genomic profiles and highlighting the potential prognostic value of APOBEC3B for GCA through routine clinical IHC.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Neoplasias do Colo do Útero , Adenocarcinoma/genética , Adenocarcinoma/patologia , Citidina Desaminase/genética , Feminino , Humanos , Antígenos de Histocompatibilidade Menor/genética , Mutação , Recidiva Local de Neoplasia , Prognóstico , Neoplasias Gástricas/genética , Neoplasias do Colo do Útero/genética
7.
World J Surg Oncol ; 20(1): 92, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35321724

RESUMO

BACKGROUND: Leukocyte immunoglobulin-like receptor subfamily B (LILRB), including 5 subtypes, is a group of inhibitory receptors in the immune system. The LILRB family is known to be involved in the tumor progression of various cancer types, especially liver cancer. However, the expression patterns and prognostic values of LILRB family members in liver cancer tissues remain unclear. METHODS: We used the Oncomine database, GEPIA database, Kaplan-Meier Plotter, Timer, and TISIDB to assess the expression and prognostic value of the LILRB family in liver cancer patients. We also verified the expression of the LILRB family in tumor tissues and tumor-free liver tissues at the protein level by using immunohistochemistry. The STRING website was used to explore the interaction between the LILRB family and their related genes. The DAVID database was used to perform the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Flow cytometry was used to assess the infiltrated NK cells in liver cancer tissues. RESULTS: Our study revealed that the mRNA expression of LILRB1, LILRB2, LILRB3, and LILRB5 was downregulated, while compared with normal tissues, the mRNA expression of LILRB4 was upregulated in liver cancer tissues. Survival analysis revealed that LILRB2 and LILRB5 mRNA expression levels were significantly positively associated with overall survival (OS) and disease-free survival (DSS) and that the mRNA expression of all LILRB family members was significantly positively correlated with recurrence-free survival (RFS) and progression-free survival (PFS). Next, we further found that the mRNA expression of all LILRB family members was significantly associated with the infiltration of B cells, CD8+ T cells, CD4+ T cells, macrophages, neutrophils, and dendritic cells in liver cancer. Finally, GO and KEGG analyses found that the LILRB family and its related genes were involved in antigen processing and presentation and natural killer cell-mediated cytotoxicity pathways. CONCLUSIONS: Our study suggested that LILRB family expression was associated with the prognosis of liver cancer patients and infiltrated immune cells. The LILRB family might be involved in antigen processing and presentation and natural killer cell-mediated cytotoxicity pathways.


Assuntos
Antígenos CD , Linfócitos T CD8-Positivos , Neoplasias Hepáticas , Receptores Imunológicos , Antígenos CD/genética , Antígenos CD/metabolismo , Humanos , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/genética , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/metabolismo , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/imunologia , Glicoproteínas de Membrana/genética , Prognóstico , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo
8.
Chemistry ; 27(71): 17818-17823, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34533232

RESUMO

Coordination polymers are promising cathode materials for rechargeable alkaline batteries. Therefore, the precise modulation of these cathodes by chemical structure and in-depth structure transform study is necessary. Here, two model coordination polymer battery cathodes were designed to demonstrate the dynamic structure-performance relationship. We studied the electrochemical performance of two kinds of nickel-based coordination polymer, comprising a planar 2D cyanide-bridged network and a 3D cyanide-bridged network pillared by pyrazine molecules. The 2D coordination polymer showed serious voltage degradation with poor rate capability, whereas the 3D coordination polymer exhibited stable voltage output coupled with high rate at various current densities. The investigation revealed the underlining relationship of plateau voltage degradation and hydrolysis process of electrodes. It was revealed that the pyrazine pillar molecules in the 3D coordination polymer could suppress the hydrolysis and lead to the in situ formation of partially hydrolyzed structure with excellent electrochemical kinetics; this exhibited obvious smaller peak separation (27 mV compared with 149 mV) and hence an almost twofold increase in capacity retention (31.9 to 50.0 %) and energy density retention (18.2 to 35.9 %) at 10 A g-1 .

9.
Eur J Clin Microbiol Infect Dis ; 40(11): 2271-2283, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34013453

RESUMO

Sitafloxacin is one of the newer generation fluoroquinolones. Considering the ever-changing antimicrobial resistance, it is necessary to monitor the activities of sitafloxacin against recent pathogenic isolates. Therefore, we determined the minimum inhibitory concentrations (MICs) of sitafloxacin and comparators by broth microdilution or agar dilution method against 1101 clinical isolates collected from 2017 to 2019 in 31 hospitals across China. Sitafloxacin was highly active against gram-positive isolates evidenced by the MICs required to inhibit the growth of 50%/90% isolates (MIC50/90): ≤ 0.03/0.25, ≤ 0.03/0.125, ≤ 0.03/2, 0.125/0.25, 0.25/2, and 0.125/0.125 mg/L for methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-susceptible coagulase-negative Staphylococcus (MSCNS), methicillin-resistant S. aureus (MRSA), methicillin-resistant CNS, Enterococcus faecalis, and Streptococcus pneumoniae, respectively. Sitafloxacin inhibited 82.8% of the MRSA strains and 97.5% of MRCNS strains. Sitafloxacin was also potent against ciprofloxacin-susceptible Escherichia coli (MIC50/90: ≤ 0.03/0.06 mg/L) and Klebsiella pneumoniae (MIC50/90: ≤ 0.03/0.125 mg/L), non-ESBL-producing E. coli (MIC50/90: ≤ 0.03/1 mg/L) and K. pneumoniae (MIC50/90: ≤ 0.03/0.5 mg/L), Haemophilus influenzae (MIC50/90: ≤0.015/0.06 mg/L), Haemophilus parainfluenzae (MIC50/90: 0.125/0.5 mg/L), Moraxella catarrhalis (MIC50/90: ≤ 0.015/≤ 0.015 mg/L), Bacteroides fragilis (MIC50/90: 0.06/2 mg/L), Peptostreptococcus (MIC50/90: 0.125/4 mg/L), and Mycoplasma pneumoniae (≤ 0.03/≤ 0.03 mg/L). However, sitafloxacin was less active for Enterococcus faecium, ciprofloxacin-resistant and/or ESBL-producing E. coli, and K. pneumoniae strains. Sitafloxacin was superior or comparable to most of the comparators in activities against the abovementioned isolates, so sitafloxacin is still highly active against most of the clinical isolates in hospitals across China, proving its utility in treatment of the abovementioned susceptible strains.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Fluoroquinolonas/uso terapêutico , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , China , Ciprofloxacina/uso terapêutico , Hospitais/estatística & dados numéricos , Humanos , Meticilina/uso terapêutico , Testes de Sensibilidade Microbiana
10.
Eur J Clin Microbiol Infect Dis ; 40(6): 1149-1154, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33411173

RESUMO

Tigecycline is an alternative antibiotic for managing carbapenem-resistant Gram-negative bacterial infections. However, disk diffusion and automated testing often show false-intermediate or false-resistant results in tigecycline susceptibility, misleading clinical antimicrobial therapy. Broth microdilution (BMD) is the reference method for testing tigecycline susceptibility, but it is labor intensive and time consuming to perform in clinical laboratories. Therefore, a simple and accurate method is urgently needed. We evaluated the performance of VITEK 2, E-test, Kirby-Bauer disk diffusion (KB), and modified KB disk diffusion (mKB) versus BMD in testing tigecycline susceptibility of 372 strains of carbapenem-resistant Klebsiella pneumoniae (CRKP) and 346 strains of carbapenem-resistant Acinetobacter baumannii (CRAB). BMD confirmed that 96.8% of CRKP and 91% of CRAB strains were susceptible to tigecycline. E-test, VITEK 2, KB, and mKB yielded categorical agreement of 96.7/59.3%, 69.9/54.3%, 78.5/87.3%, and 96.5%/91% for CRKP/CRAB, respectively. No very major error was found for either CRKP or CRAB by any method. No major error was found for CRKP or CRAB by the mKB method. The mKB method enhanced by R-buffer is simple, accurate, and inexpensive for clinical laboratories to test the susceptibility of CRKP and CRAB isolates to tigecycline.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/métodos , Farmacorresistência Bacteriana , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Tigeciclina/farmacologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/crescimento & desenvolvimento , Carbapenêmicos/farmacologia , China , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/crescimento & desenvolvimento
11.
Clin Infect Dis ; 71(Suppl 4): S436-S439, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33367577

RESUMO

This is the first report of ceftazidime-avibactam resistance caused by the blaKPC-33 mutation through the D179Y variant during the treatment of blaKPC-2-positive Klebsiella pneumoniae-related infections in China. The blaKPC-33-containing K. pneumoniae was susceptible to meropenem-vaborbactam, cefepime-zidebactam, tigecycline, and polymyxin B. The blaKPC-33 gene was located on a 77 551-bp transformable plasmid harboring qnrS1 and blaLAP-2. Detecting blaKPC-33-positive K. pneumoniae clinical strains is important for infection control.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Proteínas de Bactérias/genética , Ceftazidima , China , Combinação de Medicamentos , Humanos , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
12.
Antimicrob Agents Chemother ; 64(11)2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32816731

RESUMO

The in vitro activities of ceftaroline and tedizolid were compared against Staphylococcus aureus, Enterococcus faecalis, and Enterococcus faecium clinical isolates collected from the China Antimicrobial Surveillance Network. Ceftaroline demonstrated potent activity against S. aureus isolates (MIC50/90, ≤0.25/1 mg/liter). Tedizolid was also highly active against S. aureus (MIC50/90, 0.25/0.5 mg/liter) and Enterococcus (MIC50/90, 0.5/0.5 mg/liter) isolates. Our results support the clinical usefulness of ceftaroline and tedizolid in treating Gram-positive infections.


Assuntos
Enterococcus , Staphylococcus aureus , Antibacterianos/farmacologia , Cefalosporinas , China , Testes de Sensibilidade Microbiana , Oxazolidinonas , Tetrazóis , Ceftarolina
13.
Artigo em Inglês | MEDLINE | ID: mdl-33139291

RESUMO

This study evaluated the in vitro activity of cefepime-zidebactam in comparison with that of ceftazidime-avibactam and other comparators against clinically significant Gram-negative bacillus isolates. A total of 3,400 nonduplicate Gram-negative clinical isolates were collected from 45 medical centers across China in the CHINET Program in 2018, including Enterobacterales (n = 2,228), Pseudomonas aeruginosa (n = 657), and Acinetobacter baumannii (n = 515). The activities of cefepime-zidebactam and 20 comparators were determined by broth microdilution as recommended by the Clinical and Laboratory Standards Institute. Cefepime-zidebactam demonstrated potent activity against almost all Enterobacterales (MIC50/90, 0.125/1 mg/liter) and good activity against P. aeruginosa (MIC50/90, 2/8 mg/liter). Among the 373 carbapenem-resistant Enterobacteriaceae isolates, 57.3% (213/373) and 15.3% (57/373) were positive for blaKPC-2 and blaNDM, respectively. Cefepime-zidebactam showed a MIC of ≤2 mg/liter for 92.0% (196/213) of blaKPC-2 producers and 79.7% (47/59) of blaNDM producers. Ceftazidime-avibactam showed good in vitro activity against Enterobacterales (MIC50/90, 0.25/2 mg/liter; 94.0% susceptible) and P. aeruginosa (MIC50/90, 4/16 mg/liter; 86.9% susceptible). Ceftazidime-avibactam was active against 9.1% of carbapenem-resistant Escherichia coli isolates (63.6% were blaNDM producers) and 84.6% of Klebsiella pneumoniae isolates (74.3% were blaKPC producers). Most (90.1%) blaKPC-2 producers were susceptible to ceftazidime-avibactam. Cefepime-zidebactam demonstrated limited activity (MIC50/90, 16/32 mg/liter) against the 515 A. baumannii isolates (79.2% were carbapenem resistant), and ceftazidime-avibactam was less active (MIC50/90, 64/>64 mg/liter). Cefepime-zidebactam was highly active against clinical isolates of Enterobacterales and P. aeruginosa, including blaKPC-2-positive Enterobacterales and blaNDM-positive Enterobacterales and carbapenem-resistant P. aeruginosa And ceftazidime-avibactam was highly active against blaKPC-2-positive Enterobacterales and carbapenem-resistant P. aeruginosa.


Assuntos
Acinetobacter baumannii , Pseudomonas aeruginosa , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Ceftazidima/farmacologia , Cefalosporinas , China , Ciclo-Octanos , Combinação de Medicamentos , Enterobacteriaceae , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/genética
14.
Anal Chem ; 92(8): 6072-6080, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32216261

RESUMO

Hypochlorite (ClO-) and singlet oxygen (1O2) commonly coexist in living systems and exert important interplaying roles in many diseases. To dissect their complex inter-relationship, it is urgently required to construct a fluorescent probe that can discriminate ClO- and 1O2 in living organisms. Herein, by taking the 3-(aliphaticthio)-propan-1-one group as the unique recognition unit for both ClO- and 1O2, we proposed the first fluorescent probe, Hy-2, to simultaneously discriminate ClO- and 1O2 with high sensitivity and selectivity. Probe Hy-2 itself showed fluorescence in blue channel. After treatment with ClO- and 1O2, respectively, pronounced fluorescence enhancements were observed in the green channel and red channel correspondingly. Moreover, upon development of the probe with aggregation-induced emission (AIE) characteristics, the probe could work well in a solution with high water volume fraction. Probe Hy-2 was also able to accumulate into mitochondria and was utilized as an effective tool to image exogenous and endogenous ClO- and 1O2 in mitochondria. Significantly, as the first trial, probe Hy-2 was employed to simultaneously monitor the variation of ClO- and 1O2 level in cecal tissues of rat in the cecal ligation and puncture (CLP)-induced polymicrobial sepsis model. The results demonstrated that the expressed ClO- and 1O2 levels were tightly correlated with the severity of sepsis, inferring that the overproduction of ClO- and 1O2 is an important factor in the pathogenesis of sepsis. The probe illustrated herein may provide a guide for further exploring the functions of ClO- and 1O2 in various diseases.


Assuntos
Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Imagem Óptica , Oxigênio/análise , Sepse/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Corantes Fluorescentes/síntese química , Ratos , Ratos Sprague-Dawley
15.
Artigo em Inglês | MEDLINE | ID: mdl-30617091

RESUMO

The in vitro activities of ceftazidime-avibactam (CZA), ceftolozane-tazobactam (C-T), and comparators were determined for 1,774 isolates of Enterobacteriaceae and 524 isolates of Pseudomonas aeruginosa collected by 30 medical centers from the China Antimicrobial Surveillance Network (CHINET) in 2017. Antimicrobial susceptibility testing was performed by the CLSI broth microdilution method, and blaKPC and blaNDM were detected by PCR for all carbapenem-resistant Enterobacteriaceae (CRE). Ceftazidime-avibactam demonstrated potent activity against almost all Enterobacteriaceae (94.6% susceptibility; MIC50, ≤0.25 mg/liter; MIC90, ≤0.25 to >32 mg/liter) and good activity against P. aeruginosa (86.5% susceptibility; MIC50/90, 2/16 mg/liter). Among the CRE, 50.8% (189/372 isolates) were positive for blaKPC-2, which mainly existed in ceftazidime-avibactam-susceptible Klebsiella pneumoniae isolates (92.1%, 174/189). Among the CRE, 17.7% (66/372 isolates) were positive for blaNDM, which mainly existed in strains resistant to ceftazidime-avibactam (71.7%, 66/92). Ceftolozane-tazobactam showed good in vitro activity against Escherichia coli and Proteus mirabilis (MIC50/90, ≤0.5/2 mg/liter; 90.5 and 93.8% susceptibility, respectively), and the rates of susceptibility of K. pneumoniae (MIC50/90, 2/>64 mg/liter) and P. aeruginosa (MIC50/90, 1/8 mg/liter) were 52.7% and 88.5%, respectively. Among the CRE strains, 28.6% of E. coli isolates and 85% of K. pneumoniae isolates were still susceptible to ceftazidime-avibactam, but only 7.1% and 1.9% of them, respectively, were susceptible to ceftolozane-tazobactam. The rates of susceptibility of the carbapenem-resistant P. aeruginosa isolates to ceftazidime-avibactam (65.7%) and ceftolozane-tazobactam (68%) were similar. Overall, both ceftazidime-avibactam and ceftolozane-tazobactam were highly active against clinical isolates of Enterobacteriaceae and P. aeruginosa recently collected across China, and ceftazidime-avibactam showed activity superior to that of ceftolozane-tazobactam against Enterobacteriaceae, whereas ceftolozane-tazobactam showed a better effect against P. aeruginosa.


Assuntos
Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Ceftazidima/farmacologia , Cefalosporinas/farmacologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Tazobactam/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , China , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Infecções por Enterobacteriaceae/microbiologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Infecções por Pseudomonas/microbiologia
16.
Biochem Biophys Res Commun ; 511(2): 447-453, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30797554

RESUMO

BACKGROUND: Caspase 3 is not only involved in apoptosis, but also participates in the nonapoptotic functions. Previously, we found that caspase 3 gene knockout mice displayed decreased number of dendritic cells (DCs). However, whether caspase 3 participate in the function of DCs is unclear. Thus, the present study aims to investigate the role of caspase 3 in the maturation and antitumor function of DCs. METHODS: Caspase 3 gene was overexpressed in DC2.4 cell line through Lentivirus system. The impact of caspase 3 gene overexpression on the biological behavior of DC2.4 cells was determined by CCK-8, colony formation and apoptosis analysis. The impact of caspase 3 gene overexpression on the antigen uptake, maturation, migration, T cell activation of DC2.4 cells was analyzed with phagocytosis, transwell and mixed lymphocyte reaction assay. Tumor growth and tumor infiltrated T cells were also investigated through tumor bearing model. RESULTS: Caspase 3 gene overexpression could slightly increase the apoptosis of DC2.4 cells. Antigen uptake capability and maturation of DC2.4 cells were significantly promoted through caspases 3 gene overexpression. However, CXCR4 expression on DC2.4 cells and migration of DC2.4 cells were not influenced. Caspase 3 gene overexpression also enhanced the T cell activation and cytotoxicity of activated T cells. Finally, overexpression of caspase 3 gene significantly increased the tumor suppression of DC2.4 cells, accompanied by increased infiltration of CD4+ and CD8+ Cells in tumor tissue. CONCLUSION: Caspase 3 gene overexpression could promote maturation and enhance antitumor capability of DC2.4 cells.


Assuntos
Caspase 3/imunologia , Células Dendríticas/imunologia , Neoplasias/imunologia , Animais , Apoptose , Carcinogênese/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Imunidade , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia
17.
Immunol Invest ; 48(7): 704-718, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31044626

RESUMO

Immunoglobulin-like transcript (ILT) 4 is an inhibitory immune receptor of the immunoglobulin superfamily, which could deliver inhibitory signals and induce immunosuppression. The significance of the expression of ILT4 in mDCs subsets in patients with hepatocellular carcinoma (HCC) remains unclear. In this study, the frequency of mDCs subsets in the peripheral blood of 121 patients with HCC and 103 normal controls, and in the tumor and tumor free liver tissues (TFL) of 43 HCC patients was analyzed by flow cytometry. Then, the expressions of ILT4 in mDCs subsets in the microenvironment of liver cancer were also analyzed. Results showed that the percentage of CD1c+ subset was dramatically decreased in peripheral blood mononuclear cells (PBMCs) of HCC patients compared with normal controls, and also significantly decreased in tumor tissue compared with the TFL. The decreased of CD1c+ subset in blood could be a diagnostic factor for HCC with the area under the receiver operating characteristic curve 0.975 (P < 0.01). The percentage of ILT4+CD1c+ subset was dramatically increased in tumor than that of TFL and blood. There were significant correlations between the percentage of ILT4+ in CD1c+ subset in tumor and that of in blood. The percentage of ILT4+CD1c+ subset in tumor tissue was strongly associated with the Edmondson-Steiner stage in HCC (P = 0.03). Furthermore, the capacity of ILT4+CD1c+ subset producing IFN-γ was lower than ILT4- CD1c subset in PBMC of HCC patients following Poly I:C stimulation. Taken together, the increased ILT4+CD1c+ subset in tumor tissue might play an important role in immune suppression for patients with HCC.


Assuntos
Carcinoma Hepatocelular/imunologia , Células Dendríticas/imunologia , Neoplasias Hepáticas/imunologia , Glicoproteínas de Membrana/imunologia , Células Mieloides/imunologia , Receptores Imunológicos/imunologia , Antígenos CD1/imunologia , Biomarcadores Tumorais/imunologia , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Células Dendríticas/patologia , Feminino , Glicoproteínas/imunologia , Humanos , Interferon gama/metabolismo , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Células Mieloides/patologia , Poli I-C/farmacologia , Curva ROC , Microambiente Tumoral
18.
Int J Med Sci ; 16(5): 741-750, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31217742

RESUMO

Autophagy plays a critical role in the regulation of innate and adaptive immune responses to pathogens and tumors. A previous study utilized proteasome and lysosome inhibitors to form autophagosomes (DRibbles) and the effect of dendritic cells (DCs) loaded with DRibbles in activating antigen-specific T cells has been demonstrated in a mouse experiment and human IL-4-DC. In this study, CMV-DRibbles derived from MDA cell lines expressing cytomegalovirus (CMV) pp65 protein were loaded onto human IFN-DC and IL-4-DC derived from monocytes, respectively. We observed that CMV-DRibbles resulted in the up-regulation of HLA-DR, CD11c, and CD83, but not co-stimulatory molecules CD 80 and CD86 on IFN-DC. Meanwhile, the expression of HLA-DR, CD80, CD83, and CD86, except for CD11c on IL-4-DC loaded with CMV-DRibbles were up-regulated. Moreover, CMV-DRibbles had no ability to stimulate these two moDCs to secrete cytokines IL-6, IL-1ß and IL-10. Then, we optimized the conditions for antigen up-take by DCs and found that mature moDCs had a superior ability to up-take CMV-DRibbles compared with immature DCs in a dose-dependent manner. Furthermore, the efficiency of CMV-DRibbles up-take by IFN-DC was superior compared to IL-4-DC. Finally, we observed that mIFN-DC was significantly more efficient at stimulating autologous CMV-specific CD4+ T cells (0.39 vs. 0.28 %, p<0.05) and CD8+ T cells (0.36 vs. 0.12%, p<0.05) to secrete IFN-γ compared with mIL-4-DC. Therefore, DRibbles containing specific viral antigens were efficient activators of human antigen-specific T cells. Our results demonstrated that IFN-DC loaded with CMV-DRibbles revealed a superior ability to induce CMV-specific T cells.


Assuntos
Autofagossomos/metabolismo , Interleucina-4/genética , Linfócitos T/metabolismo , Proteínas da Matriz Viral/genética , Autofagossomos/imunologia , Autofagia/genética , Doadores de Sangue , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Regulação Viral da Expressão Gênica/genética , Humanos , Interleucina-10/genética , Interleucina-1beta/genética , Interleucina-4/imunologia , Interleucina-6/genética , Linfócitos T/imunologia , Proteínas da Matriz Viral/imunologia
19.
J Sep Sci ; 42(18): 2888-2899, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31282097

RESUMO

Elm fruits were once an important food source in the years of famine. Research on the functional compounds in elm fruits was almost unavailable. In this study, we established an efficient high-performance liquid chromatography method for the simultaneous separation of eight chlorogenic acids and 28 flavonoids in elm fruits for the first time. Total flavonoid contents ranged from 286 mg/100 g (Ulmus laciniata) to 1228 mg/100 g (U. pumila). High concentrations of rutin, quercetin 3-O-glucoside, and kaempferol derivatives were present in U. laevis, U. castaneifolia, and U. pumila, respectively. Furthermore, the fruit extracts of U. americana, U. castaneifolia, U. davidiana, and U. pumila showed higher antioxidant activity. These results suggest that fruits of these species can be used as bioresources for the extraction of the corresponding functional compounds. This work provides informative data and can be an important reference for future research on elm fruits as a renewed food resource.


Assuntos
Antioxidantes/análise , Ácido Clorogênico/análise , Flavonoides/análise , Frutas/química , Ulmus/química , Antioxidantes/farmacologia , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Ácido Clorogênico/farmacologia , Flavonoides/farmacologia , Picratos/antagonistas & inibidores , Ácidos Sulfônicos/antagonistas & inibidores
20.
Nucleic Acids Res ; 45(6): 3086-3101, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-27956498

RESUMO

Recently, long non-coding RNAs (lncRNAs) have been shown to have important regulatory roles in human cancer biology. In our study, we found that lncRNA CCAT1, whose expression is significantly increased and is correlated with outcomes in Esophageal Squamous Cell Carcinoma (ESCC). Consecutive experiments confirmed that H3K27-acetylation could activate expression of colon cancer associated transcript-1 (CCAT1). Further experiments revealed that CCAT1 knockdown significantly repressed the proliferation and migration both in vitro and in vivo. RNA-seq analysis revealed that CCAT1 knockdown preferentially affected genes that are linked to cell proliferation, cell migration and cell adhesion. Mechanistic investigations found that CCAT1 could serve as a scaffold for two distinct epigenetic modification complexes (5΄ domain of CCAT1 binding Polycomb Repressive Complex 2 (PRC2) while 3΄ domain of CCAT1 binding SUV39H1) and modulate the histone methylation of promoter of SPRY4 (sprouty RTK signaling antagonist 4) in nucleus. In cytoplasm, CCAT1 regulates HOXB13 as a molecular decoy for miR-7, a microRNA that targets both CCAT1 and HOXB13, thus facilitating cell growth and migration. Together, our data demonstrated the important roles of CCAT1 in ESCC oncogenesis and might serve as targets for ESCC diagnosis and therapy.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas do Tecido Nervoso/genética , RNA Longo não Codificante/metabolismo , Acetilação , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Feminino , Inativação Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Metiltransferases/metabolismo , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Prognóstico , RNA Longo não Codificante/fisiologia , Proteínas Repressoras/metabolismo
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