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1.
Inorg Chem ; 63(24): 11317-11324, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38829674

RESUMO

Ruddlesden-Popper oxyfluorides of the substitution series La2Ni1-xCuxO3F2 (0 ≤ x ≤ 1) were obtained by topochemical fluorination with polyvinylidene fluoride (PVDF) of oxide precursors La2Ni1-xCuxO4. The thermal stability and the temperature-dependent unit cell evolution of the oxyfluorides were investigated by high-temperature XRD measurements. The oxyfluoride with x = 0.6 shows the highest decomposition temperature of θdec ∼ 520 °C, which is significantly higher than the ones found for the end members La2NiO3F2 (x = 0) θdec ∼ 460 °C and La2CuO3F2 (x = 1) θdec ∼ 430 °C. The magnetic properties of all La2Ni1-xCuxO3F2 oxyfluorides were characterized by field- and temperature-dependent measurements as well as DFT calculations of the magnetic ground state. An antiferromagnetic ordering was derived for all substitution levels. For the Néel temperature (TN), a nonlinear dependence on the copper content was found, and comparably high values of TN in the region of 200-250 K were observed in the broad composition range of 0.3 ≤ x ≤ 0.8.

2.
J Glob Antimicrob Resist ; 38: 116-122, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38735531

RESUMO

OBJECTIVES: To investigate the clinical and molecular epidemiological characteristics of blaIMP-4-carrying Klebsiella pneumoniae in a tertiary hospital in China. METHODS: Ten carbapenem-resistant K. pneumoniae (CRKP) isolates carrying the blaIMP-4 gene were collected. Molecular characteristics were analysed using whole-genome sequencing. Plasmid conjugation experiments were used to analyse conjugation of the plasmids. We compared and analysed K. pneumoniae-carrying blaIMP-4 genomic datasets obtained from the National Center for Biotechnology Information (NCBI) with the strains in this study. RESULTS: All 10 CRKP isolates carrying blaIMP-4 were collected from 10 adult patients in the respiratory intensive care unit. These strains were only sensitive to polymyxins and tigecycline due to them simultaneously carrying multiple resistance genes, namely blaOKP-A-5, fosA, oqxA, and oqxB. Notably, R29 harboured two carbapenemase genes (blaNDM-1 and blaIMP-4). These strains had similar drug-resistant phenotypes and genes, all belonging to sequence type (ST)196. Additionally, the patients had experienced spatiotemporal intersection during hospitalization, suggesting that these strains underwent clonal transmission, but they belonged to different clonal clusters from the blaIMP-4-positive K. pneumoniae currently published in the NCBI. Among the 10 strains, blaIMP-4 was located on the IncN plasmid, and six strains had successfully transferred the plasmid to the recipient strain EC600 through plasmid conjugation. CONCLUSIONS: The blaIMP-4-positive ST196 CRKP isolate showed clonal distribution in the respiratory intensive care unit, which was mediated by the IncN plasmid. Consequently, there should be increased monitoring of carbapenem-resistant strains in clinical settings to prevent and control its transmission.

3.
Inorg Chem ; 63(13): 6075-6081, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38506110

RESUMO

Ruddlesden-Popper oxyfluorides La2Ni1-xCuxO3F2 (0 ≤ x ≤ 1) were obtained by topochemical reaction of oxide precursors La2Ni1-xCuxO4, prepared by citrate-based soft chemistry synthesis, with polyvinylidene fluoride (PVDF) as the fluorine source. Systematic changes of the crystal structure in the oxide as well as the oxyfluoride substitution series were investigated. For 0.2 ≤ x ≤ 0.9, the oxyfluorides adopt the monoclinic (C2/c) structural distortion previously solved for the x = 0.8 compound based on neutron powder diffraction data, whereas the sample with a lower Cu content of x = 0.1 crystallizes in the orthorhombic (Cccm) structure variant of La2NiO3F2. The orthorhombic-to-monoclinic structural transition was found to be the result of an additional tilt component of the Jahn-Teller elongated CuO4F2 octahedra. The structural transitions were additionally studied by DFT calculations, confirming the monoclinic space group symmetry. The "channel-like" anionic ordering of the endmembers La2NiO3F2 and La2CuO3F2 was checked by 19F MAS NMR experiments and was found to persist throughout the entire substitution series.

4.
Ann Clin Microbiol Antimicrob ; 23(1): 13, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347529

RESUMO

BACKGROUND: Recently, extensively drug-resistant Pseudomonas aeruginosa (XDR-PA) isolates have been increasingly detected and posed great challenges to clinical anti-infection treatments. However, little is known about extensively resistant hypervirulent P. aeruginosa (XDR-hvPA). In this study, we investigate its epidemiological characteristics and provide important basis for preventing its dissemination. METHODS: Clinical XDR-PA isolates were collected from January 2018 to January 2023 and identified using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry; antibiotic susceptibility testing was performed by broth microdilution method, and minimum inhibitory concentrations (MICs) were evaluated. Virulence was evaluated using the Galleria mellonella infection model; molecular characteristics, including resistance genes, virulence genes, and homology, were determined using whole-genome sequencing. RESULTS: A total of 77 XDR-PA strains were collected; 47/77 strains were XDR-hvPA. Patients aged > 60 years showed a significantly higher detection rate of XDR-hvPA than of XDR-non-hvPA. Among the 47 XDR-hvPA strains, 24 strains carried a carbapenemase gene, including blaGES-1 (10/47), blaVIM-2 (6/47), blaGES-14 (4/47), blaIMP-45 (2/47), blaKPC-2 (1/47), and blaNDM-14 (1/47). ExoU, exoT, exoY, and exoS, important virulence factors of PA, were found in 31/47, 47/47, 46/47, and 29/47 strains, respectively. Notably, two XDR-hvPA simultaneously co-carried exoU and exoS. Six serotypes (O1, O4-O7, and O11) were detected; O11 (19/47), O7 (13/47), and O4 (9/47) were the most prevalent. In 2018-2020, O4 and O7 were the most prevalent serotypes; 2021 onward, O11 (16/26) was the most prevalent serotype. Fourteen types of ST were detected, mainly ST235 (14/47), ST1158 (13/47), and ST1800 (7/47). Five global epidemic ST235 XDR-hvPA carried blaGES and showed the MIC value of ceftazidime/avibactam reached the susceptibility breakpoint (8/4 mg/L). CONCLUSIONS: The clinical detection rate of XDR-hvPA is unexpectedly high, particularly in patients aged > 60 years, who are seemingly more susceptible to contracting this infection. Clonal transmission of XDR-hvPA carrying blaGES, which belongs to the global epidemic ST235, was noted. Therefore, the monitoring of XDR-hvPA should be strengthened, particularly for elderly hospitalized patients, to prevent its spread.


Assuntos
Antibacterianos , Infecções por Pseudomonas , Idoso , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Pseudomonas aeruginosa/genética , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/tratamento farmacológico , Proteínas de Bactérias/genética , beta-Lactamases/genética , Sorogrupo , China/epidemiologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla/genética
5.
BMC Genomics ; 25(1): 216, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413855

RESUMO

BACKGROUND: Shewanella xiamenensis, widely distributed in natural environments, has long been considered as opportunistic pathogen. Recently, significant changes in the resistance spectrum have been observed in S. xiamenensis, due to acquired antibiotic resistance genes. Therefore, a pan-genome analysis was conducted to illuminate the genomic changes in S. xiamenensis. RESULTS: Phylogenetic analysis revealed three major clusters and three singletons, among which close relationship between several strains was discovered, regardless of their host and niches. The "open" genomes with diversity of accessory and strain-specific genomes took advantage towards diversity environments. The purifying selection pressure was the main force on genome evolution, especially in conservative genes. Only 53 gene families were under positive selection pressure. Phenotypic resistance analysis revealed 21 strains were classified as multi-drug resistance (MDR). Ten types of antibiotic resistance genes and two heavy metal resistance operons were discovered in S. xiamenensis. Mobile genetic elements and horizontal gene transfer increased genome diversity and were closely related to MDR strains. S. xiamenensis carried a variety of virulence genes and macromolecular secretion systems, indicating their important roles in pathogenicity and adaptability. Type IV secretion system was discovered in 15 genomes with various sequence structures, indicating it was originated from different donors through horizontal gene transfer. CONCLUSIONS: This study provided with a detailed insight into the changes in the pan-genome of S. xiamenensis, highlighting its capability to acquire new mobile genetic elements and resistance genes for its adaptation to environment and pathogenicity to human and animals.


Assuntos
Variação Genética , Genoma Bacteriano , Shewanella , Animais , Humanos , Virulência/genética , Filogenia , Resistência Microbiana a Medicamentos
6.
World J Gastroenterol ; 29(39): 5435-5451, 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37900996

RESUMO

Small extracellular vesicles (exosomes) are important components of the tumor microenvironment. They are small membrane-bound vesicles derived from almost all cell types and play an important role in intercellular communication. Exosomes transmit biological molecules obtained from parent cells, such as proteins, lipids, and nucleic acids, and are involved in cancer development. MicroRNAs (miRNAs), the most abundant contents in exosomes, are selectively packaged into exosomes to carry out their biological functions. Recent studies have revealed that exosome-delivered miRNAs play crucial roles in the tumorigenesis, progression, and drug resistance of hepatocellular carcinoma (HCC). In addition, exosomes have great industrial prospects in the diagnosis, treatment, and prognosis of patients with HCC. This review summarized the composition and function of exosomal miRNAs of different cell origins in HCC and highlighted the association between exosomal miRNAs from stromal cells and immune cells in the tumor microenvironment and the progression of HCC. Finally, we described the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Exossomos , Vesículas Extracelulares , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/metabolismo , Exossomos/genética , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Microambiente Tumoral/genética
7.
J Phys Chem Lett ; 14(44): 9969-9977, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37905788

RESUMO

We study two-dimensional noble metal chalcogenides, with compositions {Cu, Ag, Au}2{S, Se, Te}, crystallizing in a snub-square lattice. This is a semiregular two-dimensional tesselation formed by triangles and squares that exhibits geometrical frustration. We use for comparison a square lattice, from which the snub-square tiling can be derived by a simple rotation of the squares. The monolayer snub-square chalcogenides are very close to thermodynamic stability, with the most stable system (Ag2Se) a mere 7 meV/atom above the convex hull of stability. All compounds studied in the square and snub-square lattice are semiconductors, with band gaps ranging from 0.1 to more than 2.5 eV. Excitonic effects are strong, with an exciton binding energy of around 0.3 eV. We propose the Cu (001) surface as a possible substrate to synthesize Cu2Se, although many other metal and semiconducting surfaces can be found with very good lattice matching.

8.
Neuron ; 111(17): 2709-2726.e9, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37348508

RESUMO

Programmed death protein 1 (PD-1) and its ligand PD-L1 constitute an immune checkpoint pathway. We report that neuronal PD-1 signaling regulates learning/memory in health and disease. Mice lacking PD-1 (encoded by Pdcd1) exhibit enhanced long-term potentiation (LTP) and memory. Intraventricular administration of anti-mouse PD-1 monoclonal antibody (RMP1-14) potentiated learning and memory. Selective deletion of PD-1 in excitatory neurons (but not microglia) also enhances LTP and memory. Traumatic brain injury (TBI) impairs learning and memory, which is rescued by Pdcd1 deletion or intraventricular PD-1 blockade. Conversely, re-expression of Pdcd1 in PD-1-deficient hippocampal neurons suppresses memory and LTP. Exogenous PD-L1 suppresses learning/memory in mice and the excitability of mouse and NHP hippocampal neurons through PD-1. Notably, neuronal activation suppresses PD-L1 secretion, and PD-L1/PD-1 signaling is distinctly regulated by learning and TBI. Thus, conditions that reduce PD-L1 levels or PD-1 signaling could promote memory in both physiological and pathological conditions.


Assuntos
Antígeno B7-H1 , Lesões Encefálicas Traumáticas , Humanos , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Aprendizagem , Hipocampo/metabolismo , Anticorpos Monoclonais/metabolismo , Neurônios/metabolismo
9.
Int J Nanomedicine ; 18: 2485-2502, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37192897

RESUMO

Purpose: As an under-explored biomaterial, bacterial biofilms have a wide range of applications in the green synthesis of nanomaterials. The biofilm supernatant of Pseudomonas aeruginosa PA75 was used to synthesize novel silver nanoparticles (AgNPs). BF75-AgNPs were found to possess several biological properties. Methods: In this study, we biosynthesized BF75-AgNPs using biofilm supernatant as the reducing agent, stabilizer, and dispersant and investigated their biopotential in terms of antibacterial, antibiofilm, and antitumor activities. Results: The synthesized BF75-AgNPs demonstrated a typical face-centered cubic crystal structure; they were well dispersed; and they were spherical with a size of 13.899 ± 4.036 nm. The average zeta potential of the BF75-AgNPs was -31.0 ± 8.1 mV. The BF75-AgNPs exhibited strong antibacterial activities against the methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum beta-lactamase Escherichia coli (ESBL-EC), extensively drug-resistant Klebsiella pneumoniae (XDR-KP), and carbapenem-resistant Pseudomonas aeruginosa (CR-PA). Moreover, the BF75-AgNPs had a strong bactericidal effect on XDR-KP at 1/2 × MIC, and the expression level of reactive oxygen species (ROS) in bacteria was significantly increased. A synergistic effect was observed when the BF75-AgNPs and colistin were used for the co-treatment of two colistin-resistant XDR-KP strains, with fractional inhibitory concentration index (FICI) values of 0.281 and 0.187, respectively. Furthermore, the BF75-AgNPs demonstrated a strong biofilm inhibition activity and mature biofilm bactericidal activity against XDR-KP. The BF75-AgNPs also exhibited a strong antitumor activity against melanoma cells and low cytotoxicity against normal epidermal cells. In addition, the BF75-AgNPs increased the proportion of apoptotic cells in two melanoma cell lines, and the proportion of late apoptotic cells increased with BF75-AgNP concentration. Conclusion: This study suggests that BF75-AgNPs synthesized from biofilm supernatant have broad prospects for antibacterial, antibiofilm, and antitumor applications.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Colistina/farmacologia , Pseudomonas aeruginosa , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Antibacterianos/química , Biofilmes
10.
Environ Res ; 228: 115866, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37037312

RESUMO

Hospital wastewater contains large amounts of antibiotic-resistant bacteria and serves as an important reservoir for horizontal gene transfer (HGT). However, the response of the microbiome in hospital wastewater to silver remains unclear. In this study, the short-term impacts of silver on the microbiome in hospital wastewater were investigated by metagenome next-generation sequencing. The influence of silver on the conjugation of plasmid carrying blaNDM-1 was further examined. Our results showed that in hospital wastewater, high abundances of antibiotic resistance genes (ARGs) were detected. The distribution tendencies of certain ARG types on chromosomes or plasmids were different. Clinically important ARGs were identified in phage-like contigs, indicating potential transmission via transduction. Pseudomonadales, Enterobacterales, and Bacteroidales were the major ARG hosts. Mobile genetic elements were mainly detected in plasmids and associated with various types of ARGs. The binning approach identified 29 bins that were assigned to three phyla. Various ARGs and virulence factors were identified in 14 and 11 bins, respectively. MetaCHIP identified 49 HGT events. The transferred genes were annotated as ARGs, mobile genetic elements, and functional genes, and they mainly originated from donors belonging to Bacteroides and Pseudomonadales. In addition, 20 nm AgNPs reduced microbial diversity and enhanced the relative abundance of Acinetobacter. The changes induced by 20 nm AgNPs included increases in the abundances of ARGs and genes involved lipid metabolism pathway. Conjugation experiments showed that Ag+ and 20 nm AgNPs caused 2.38-, 3.31-, 4.72-, and 4.57-fold and 1.46-, 1.61-, 3.86-, and 2.16-fold increases in conjugation frequencies of plasmid with blaNDM-1 at 0.1, 1, 10, and 100 µg/L, respectively. Our findings provide insight into the response of the microbiome in hospital wastewater to silver, emphasize the adaptation capability of Acinetobacter inhabiting hospitals against adverse environments, and highlight the promotion of silver for antibiotic resistance.


Assuntos
Nanopartículas Metálicas , Microbiota , Águas Residuárias , Prata , Metagenoma , Antibacterianos/farmacologia , Genes Bacterianos , Hospitais
11.
BMC Microbiol ; 23(1): 64, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882683

RESUMO

BACKGROUND: The prevalence of multidrug-resistant hypervirulent K. pneumoniae (MDR-hvKP) has gradually increased. It poses a severe threat to human health. However, polymyxin-resistant hvKP is rare. Here, we collected eight polymyxin B-resistant K. pneumoniae isolates from a Chinese teaching hospital as a suspected outbreak. RESULTS: The minimum inhibitory concentrations (MICs) were determined by the broth microdilution method. HvKP was identified by detecting virulence-related genes and using a Galleria mellonella infection model. Their resistance to serum, growth, biofilm formation, and plasmid conjugation were analyzed in this study. Molecular characteristics were analyzed using whole-genome sequencing (WGS) and mutations of chromosome-mediated two-component systems pmrAB and phoPQ, and the negative phoPQ regulator mgrB to cause polymyxin B (PB) resistance were screened. All isolates were resistant to polymyxin B and sensitive to tigecycline; four were resistant to ceftazidime/avibactam. Except for KP16 (a newly discovered ST5254), all were of the K64 capsular serotype and belonged to ST11. Four strains co-harbored blaKPC-2, blaNDM-1, and the virulence-related genes prmpA, prmpA2, iucA, and peg344, and were confirmed to be hypervirulent by the G. mellonella infection model. According to WGS analysis, three hvKP strains showed evidence of clonal transmission (8-20 single nucleotide polymorphisms) and had a highly transferable pKOX_NDM1-like plasmid. KP25 had multiple plasmids carrying blaKPC-2, blaNDM-1, blaSHV-12, blaLAP-2, tet(A), fosA5, and a pLVPK-like virulence plasmid. Tn1722 and multiple additional insert sequence-mediated transpositions were observed. Mutations in chromosomal genes phoQ and pmrB, and insertion mutations in mgrB were major causes of PB resistance. CONCLUSIONS: Polymyxin-resistant hvKP has become an essential new superbug prevalent in China, posing a serious challenge to public health. Its epidemic transmission characteristics and mechanisms of resistance and virulence deserve attention.


Assuntos
Farmacorresistência Bacteriana Múltipla , Infecções por Klebsiella , Klebsiella pneumoniae , Polimixina B , Humanos , China/epidemiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Polimixina B/farmacologia , Centros de Atenção Terciária , Surtos de Doenças , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/transmissão
12.
Adv Mater ; 35(22): e2210788, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36949007

RESUMO

Crystal-graph attention neural networks have emerged recently as remarkable tools for the prediction of thermodynamic stability. The efficacy of their learning capabilities and their reliability is however subject to the quantity and quality of the data they are fed. Previous networks exhibit strong biases due to the inhomogeneity of the training data. Here a high-quality dataset is engineered to provide a better balance across chemical and crystal-symmetry space. Crystal-graph neural networks trained with this dataset show unprecedented generalization accuracy. Such networks are applied to perform machine-learning-assisted high-throughput searches of stable materials, spanning 1 billion candidates. In this way, the number of vertices of the global T = 0 K phase diagram is increased by 30% and find more than ≈150 000 compounds with a distance to the convex hull of stability of less than 50 meV atom-1 . The discovered materials are then accessed for applications, identifying compounds with extreme values of a few properties, such as superconductivity, superhardness, and giant gap-deformation potentials.

13.
Neurospine ; 19(3): 671-686, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36203293

RESUMO

Physical rehabilitation is essential for enhancing recovery in individuals with spinal cord injury (SCI); however, aside from early surgical intervention and hemodynamic management, there are no proven interventions for promoting recovery in the acute phase. In general, early rehabilitation is considered beneficial, but optimal parameters and potential contraindications for implementing rehabilitation at very early time points are unclear. Moreover, clinical trials to date are limited to studies initiating rehabilitation 2 weeks after injury and later. To address these gaps, this article reviews the preclinical literature on physical interventions initiated within the first 8 days postinjury. Effects of early rehabilitation on molecular and structural nervous system changes, behavioral function, and body systems are considered. Most studies utilized treadmill or cycle training as the primary intervention. Treadmill training initiated within the first 3 days and terminated by 1 week after injury worsened autonomic function, inflammation, and locomotor outcomes, while swim training during this period increased microvascular dysfunction. In contrast, lower-intensity rehabilitation such as reach training, ladder training, or voluntary wheel or ball training showed benefits when implemented during the first 3 days. Rehabilitation initiated at 4 days postinjury was also associated with enhanced motor recovery. Cycling appears to have the greatest risk-benefit ratio; however, the effects of cycle training in the first 3 days were not investigated. Overall, research suggests that lower intensity or voluntary rehabilitation during the hyperacute phase is more appropriate until at least 4 days postinjury, at which point higher-intensity activity becomes safer and more beneficial for recovery.

14.
Neurospine ; 19(3): 689-702, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36203295

RESUMO

Acute traumatic spinal cord injury (SCI) can be a devastating and costly event for individuals, their families, and the health system as a whole. Prognosis is heavily dependent on the physical extent of the injury and the severity of neurological dysfunction. If not treated urgently, individuals can suffer exacerbated secondary injury cascades that may increase tissue injury and limit recovery. Initial recognition and rapid treatment of acute SCI are vital to limiting secondary injury, reducing morbidity, and providing the best chance of functional recovery. This article aims to review the pathophysiology of SCI and the most up-to-date management of the acute traumatic SCI, specifically examining the modern approaches to surgical treatments along with the ethical limitations of research in this field.

15.
Oxid Med Cell Longev ; 2022: 7608712, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36071871

RESUMO

Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase involved in cell proliferation, invasion, angiogenesis, and metastasis in various cancers, including hepatocellular carcinoma (HCC). However, the role and molecular mechanisms of EZH2 in HCC radiosensitivity remain unclear. Here, we show that EZH2 is upregulated in HCC cells and the aberrantly overexpressed EZH2 is associated with the poor prognosis of HCC patients. Using miRNA databases, we identified miR-138-5p as a regulator of EZH2. We also found that miR-138-5p was suppressed by EZH2-induced H3K27me3 in HCC cell lines. MiR-138-5p overexpression and EZH2 knockdown enhanced cellular radiosensitivity while inhibiting cell migration, invasion, and epithelial-mesenchymal transition (EMT). Analysis of RNA-seq datasets revealed that the hypoxia-inducible factor-1 (HIF-1) signaling pathway was the main enrichment pathway for differential genes after miR-138-5p overexpression or EZH2 knockdown. Expression level of HIF-1α was significantly suppressed after miR-138-5p overexpression or silencing of EZH2. HIF-1α silencing mitigated resistance of HCC cells and inhibited EMT. This study establishes the EZH2/miR-138-5p/HIF-1α as a potential therapeutic target for sensitizing HCC to radiotherapy.


Assuntos
Carcinoma Hepatocelular , Proteína Potenciadora do Homólogo 2 de Zeste , Subunidade alfa do Fator 1 Induzível por Hipóxia , Neoplasias Hepáticas , MicroRNAs , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/radioterapia , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/radioterapia , MicroRNAs/genética , MicroRNAs/metabolismo , Tolerância a Radiação/genética
16.
Front Cell Infect Microbiol ; 12: 925440, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36004330

RESUMO

Despite being a significant public health concern, hypervirulent Klebsiella pneumoniae (hvKP) has rarely been investigated in urinary tract infections (UTIs). To investigate the molecular and clinical characterization of hvKP in UTIs, we collected K. pneumoniae strains and clinical data from patients with UTIs. HvKP was confirmed by virulence-related genes and the Galleria mellonella model and sequenced by next-generation sequencing. Our data showed that 30/121 isolates were hvKP [17 carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP), 12 hvKP, and 1 extended-spectrum ß-lactamase-producing hvKP]; these had higher resistance to most antimicrobials and were more likely to cause complicated UTIs (cUTIs). Notably, the mucoid phenotype-regulating genes prmpA and prmpA2 were truncated in 3 and 19 hvKP, respectively. Eight serotypes were detected and divided into three groups: K64 (n = 17), K1/K2 (n = 6), and others (n = 7). Furthermore, 16/17 K64 hvKP isolates were CR-hvKP but with a lower mortality rate of G. mellonella as the truncated prmpA/prmpA2 incurred high fitness cost to the isolates. In addition, all K64 isolates belonged to ST11 with the same cluster, and in two of these strains (KP88 and KP92) bla KPC-2 gene was successfully transferred to EC600. Genetic environment analysis showed that IS26-tnpR-ISKpn27-bla KPC-2-ISKpn6 may be the core structure in the horizontal transfer of bla KPC-2. The highest mortality rate among the infected G. mellonella was observed in the K1/K2 group. In conclusion, hvKP had a higher resistance rate and was more likely to lead to cUTIs. Convergence of hypervirulence and carbapenem resistance in a transmissible ST11 clone of K64 K. pneumoniae was mediated by a plasmid in UTIs. Therefore, surveillance of hvKP in UTIs should be strengthened.


Assuntos
Infecções por Klebsiella , Infecções Urinárias , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Humanos , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae , Virulência/genética
17.
Exp Brain Res ; 240(9): 2413-2423, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35841411

RESUMO

The treatment of traumatic brain injury (TBI) in military populations is hindered by underreporting and underdiagnosis. Clinical symptoms and outcomes may be mitigated with an effective pre-injury prophylaxis. This study evaluates whether CN-105, a 5-amino acid apolipoprotein E (ApoE) mimetic peptide previously shown to modify the post-traumatic neuroinflammatory response, would maintain its neuroprotective effects if administered prior to closed-head injury in a clinically relevant murine model. CN-105 was synthesized by Polypeptide Inc. (San Diego, CA) and administered to C57-BL/6 mice intravenously (IV) and/or by intraperitoneal (IP) injection at various time points prior to injury while vehicle treated animals received IV and/or IP normal saline. Animals were randomized following injury and behavioral observations were conducted by investigators blinded to treatment. Vestibulomotor function was assessed using an automated Rotarod (Ugo Basile, Comerio, Italy), and hippocampal microglial activation was assessed using F4/80 immunohistochemical staining in treated and untreated mice 7 days post-TBI. Separate, in vivo assessments of the pharmacokinetics was performed in healthy CD-1. IV CN-105 administered prior to head injury improved vestibulomotor function compared to vehicle control-treated animals. CN-105 co-administered by IP and IV dosing 6 h prior to injury also improved vestibulomotor function up to 28 days following injury. Microglia counted in CN-105 treated specimens were significantly fewer (P = 0.03) than in vehicle specimens. CN-105 improves functional outcomes and reduces hippocampal microglial activation when administered prior to injury and could be adapted as a pre-injury prophylaxis for soldiers at high risk for TBI.


Assuntos
Lesões Encefálicas Traumáticas , Traumatismos Cranianos Fechados , Fármacos Neuroprotetores , Animais , Lesões Encefálicas Traumáticas/tratamento farmacológico , Modelos Animais de Doenças , Traumatismos Cranianos Fechados/complicações , Traumatismos Cranianos Fechados/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Microglia , Fármacos Neuroprotetores/farmacologia
18.
Clin Ther ; 44(5): 744-754, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35562205

RESUMO

PURPOSE: CN-105 is an IV, apolipoprotein E-mimetic pentapeptide. Preclinical studies have reported that CN-105 effectively down-regulates neuroinflammatory responses in microglia and mitigates neuronal excitotoxicity following acute brain injury. The CN-105 Phase I and II trials that have been done in the United States have demonstrated that CN-105 was well tolerated in US participants. Thus, the main objective of the present Phase I study was to investigate the tolerability and pharmacokinetic (PK) profiles of CN-105 in healthy Chinese participants. METHODS: This randomized, double-blind, placebo-controlled, dose-escalation study was performed in healthy participants using sequential 30-minute IV administration of single and multiple doses of CN-105 (four times daily for 13 doses). Forty volunteers were randomly assigned, in an 8:2 ratio, to one of four dosing groups, receiving either CN-105 (0.03, 0.1, 0.3, or 1 mg/kg), or placebo. Serial blood samples were collected for the measurement of plasma concentrations of CN-105. Tolerability was also assessed. FINDINGS: After single-dose administration, the plasma CN-105 concentration rapidly reached the peak by the end of infusion. The mean elimination half-life of CN-105 ranged from 2.3 to 3.6 hours. During single- and multiple-dosing paradigms, exposure to CN-105 (AUC) exhibited linear dependency on dose. Steady state was reached by the fourth dose, with minimal accumulation. The PK properties of CN-105 with single and multiple dosing were comparable to those observed in US participants. CN-105 was generally well tolerated in Chinese participants. A total of 13 adverse events were reported in 30% of subjects (12/40) at the 0.03 mg/kg (6/8), 0.1 mg/kg (1/8), 0.3 mg/kg (2/8), 1 mg/kg (0/8) doses and with placebo (3/8). All adverse events were mild or moderate in severity and self-limited, with no dose relationship observed. IMPLICATIONS: CN-105 was well tolerated in these healthy Chinese participants at doses of 0.1 to 1 mg/kg with single and multiple IV administrations. The PK characteristics of CN-105 were comparable among Chinese and Western subjects. A Phase II study in patients with intracranial hemorrhage is being planned in China. CLINICALTRIALS: gov identifiers: NCT02670824 and NCT03168581; Chinese Clinical Trial Registration identifier: CTR20202397.


Assuntos
Povo Asiático , Administração Oral , Área Sob a Curva , China , Relação Dose-Resposta a Droga , Método Duplo-Cego , Voluntários Saudáveis , Humanos
19.
Gynecol Oncol ; 166(1): 138-147, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35595569

RESUMO

OBJECTIVE: The role of kallikrein-related peptidase 5 (KLK5) has been studied in several diseases, including skin and ovarian cancers. However, its role in cervical cancer remains unclear, particularly in regulating the radiation resistance and growth of cervical cancer cells. Radiation resistance of cervical cancer is associated with local recurrence, distant metastasis, and reduced survival. METHODS: We first analyzed radiotherapy-naive samples and relevant clinical data from patients with cervical cancer who received radiotherapy without surgery or other antitumor treatment from 2014 to 2016. Subsequently, biopsied tissues, in vitro cells, and transplanted tumors in nude mice were investigated. RESULTS: Gene sequencing and clinical data analysis showed that KLK5 overexpression was associated with a poor prognosis post-radiotherapy. In in vitro cell and tumor transplantation experiments, KLK5 overexpression significantly increased radiation resistance. However, downregulating KLK5 expression increased radiosensitivity. CONCLUSION: Our results confirm that KLK5 is vital to the radioresistance of cervical cancer, and provide a new target and marker for the treatment of radioresistance in cervical cancer.


Assuntos
Calicreínas , Neoplasias do Colo do Útero , Agressão , Animais , Biomarcadores Tumorais/genética , Feminino , Humanos , Calicreínas/genética , Camundongos , Camundongos Nus , Tolerância a Radiação/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/radioterapia
20.
Infect Drug Resist ; 15: 1651-1657, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422644

RESUMO

Phialemonium species are a class of opportunistic pathogenic fungi widely present in the environment that cause invasive diseases in hosts with normal or weak immune functions. Common infections include peritonitis, endocarditis, osteomyelitis, and skin infections of wounds after burns, whereas endophthalmitis is rarely reported. Here, we report acute post-cataract endophthalmitis caused by Phialemoniopsis curvata in China. The isolated pathogen was identified using microscopy, culture, and sequencing. After vitrectomy, intraocular lens removal surgery, voriconazole injection, and topical voriconazole treatment, the patient's symptoms were alleviated.

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