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1.
Drug Resist Updat ; 67: 100918, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36610180

RESUMEN

Almost all the formation of hypervirulent and carbapenem-resistant Klebsiella pneumoniae follow two major patterns: KL1/KL2 hvKP strains acquire carbapenem-resistance plasmids (CR-hvKP), and carbapenem-resistant Klebsiella pneumoniae (CRKP) strains obtain virulence plasmids (hv-CRKP). These two patterns may pose different phenotypes. In this study, three typical resistance and hypervirulent K. pneumoniae (KL1, KL2, and ST11-KL64), isolating from poor prognosis patients, were selected. Compared with ST11-KL64 hv-CRKP, KL1/KL2 hypervirulent lineages harbor significantly fewer resistance determinants and exhibited lower-level resistance to antibiotics. Notably, though the blaKPC gene could be detected in all these isolates, KL1/KL2 hvKP strain did not exhibit corresponding high-level carbapenem resistance. Unlike the resistance features, we did not observe significant virulence differences between the three strains. The ST11-KL64 hv-CRKP (1403) in this study, showed similar mucoviscosity, siderophores production, and biofilm production compared with KL1 and KL2 hvKP. Moreover, the hypervirulent of ST11-KL64 hvKP also verified with the human lung epithelial cells infection and G. mellonella infection models. Moreover, we found the pLVPK-like virulence plasmid and IncF blaKPC-2 plasmid was crucial for the formation of hypervirulent and carbapenem-resistant K. pneumoniae. The conservation of origin of transfer site (oriT) in these virulence and blaKPC-2 plasmids, indicated the virulence plasmids could transfer to CRKP with the help of blaKPC-2 plasmids. The co-existence of virulence plasmid and blaKPC-2 plasmid facilitate the formation of ST11-KL64 hv-CPKP, which then become nosocomial epidemic under the antibiotic stress. The ST11-KL64 hv-CPKP may poses a substantial threat to healthcare networks, urgent measures were needed to prevent further dissemination in nosocomial settings.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos , Infección Hospitalaria , Infecciones por Klebsiella , Humanos , Klebsiella pneumoniae/genética , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , beta-Lactamasas/genética
2.
Small ; 19(26): e2207716, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36938701

RESUMEN

Metal selenides are considered as one of the most promising anode materials for Na-ion batteries owing to high specific capacity and relatively higher electronic conductivity compared with metal sulfides or oxides. However, such anodes still suffer from huge volume change upon repeated Na+ insertion/extraction processes and simultaneously undergo severe shuttle effect of polyselenides, thus leading to poor electrochemical performance. Herein, a facile chemical-blowing and selenization strategy to fabricate 3D interconnected hybrids built from metal selenides (MSe, M = Mn, Co, Cr, Fe, In, Ni, Zn) nanoparticles encapsulated in in situ formed N-doped carbon foams (NCFs) is reported. Such hybrids not only provide ultrasmall active nanobuilding blocks (≈15 nm), but also efficiently anchor them inside the conductive NCFs, thus enabling both high-efficiency utilization of active components and high structural stability. On the other hand, Cu-driven replacement reaction is utilized for efficiently inhibiting the shuttle effect of polyselenides in ether-based electrolyte. Benefiting from the combined merits of the unique MSe@NCFs and the utilization of the conversion of metal selenides to copper selenides, the as-obtained hybrids (MnSe as an example) exhibit superior rate capability (386.6 mAh g-1 up to 8 A g-1 ) and excellent cycling stability (347.7 mAh g-1 at 4.0 A g-1 after 1200 cycles).

3.
Plant Physiol ; 190(4): 2430-2448, 2022 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-36053177

RESUMEN

Cucurbitales are an important order of flowering plants known for encompassing edible plants of economic and medicinal value and numerous ornamental plants of horticultural value. By reanalyzing the genomes of two representative families (Cucurbitaceae and Begoniaceae) in Cucurbitales, we found that the previously identified Cucurbitaceae common paleotetraploidization that occurred shortly after the core-eudicot-common hexaploidization event is shared by Cucurbitales, including Begoniaceae. We built a multigenome alignment framework for Cucurbitales by identifying orthologs and paralogs and systematically redating key evolutionary events in Cucurbitales. Notably, characterizing the gene retention levels and genomic fractionation patterns between subgenomes generated from different polyploidizations in Cucurbitales suggested the autopolyploid nature of the Begoniaceae common tetraploidization and the allopolyploid nature of the Cucurbitales common tetraploidization and the Cucurbita-specific tetraploidization. Moreover, we constructed the ancestral Cucurbitales karyotype comprising 17 proto-chromosomes, confirming that the most recent common ancestor of Cucurbitaceae contained 15 proto-chromosomes and rejecting the previous hypothesis for an ancestral Cucurbitaceae karyotype with 12 proto-chromosomes. In addition, we found that the polyploidization and tandem duplication events promoted the expansion of gene families involved in the cucurbitacin biosynthesis pathway; however, gene loss and chromosomal rearrangements likely limited the expansion of these gene families.


Asunto(s)
Cucurbitaceae , Magnoliopsida , Genoma de Planta/genética , Evolución Molecular , Filogenia , Magnoliopsida/genética , Cucurbitaceae/genética , Poliploidía
4.
Appl Opt ; 62(25): 6603-6608, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37706791

RESUMEN

A low-crosstalk 3D display without color moiré patterns based on color light source array is proposed. The proposed 3D display consists of a color light source array, a transparent liquid crystal display (T-LCD) panel, a scattering layer, and a parallax barrier from back to front. The color light source array consists of three primary color light sources that correspond to the sub-pixels on the T-LCD panel. These light sources project the sub-pixels with matching color to the same location on the scattering layer to form new pixels without color moiré patterns. The new pixels have inter-pixel gaps that enhance signal bandwidth and decrease crosstalk. The parallax barrier projects the new pixels of parallax images to different viewpoints, creating a 3D effect. A prototype is developed and evaluated.

5.
Emerg Infect Dis ; 28(7): 1421-1430, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35731165

RESUMEN

Carbapenem-resistant Enterobacterales (CRE) infection is highly endemic in China; Klebsiella pneumoniae carbapenemase (KPC) 2-producing CRE is the most common, whereas KPC-3-producing CRE is rare. We report an outbreak of KPC-3-producing Enterobacterales infection in China. During August 2020-June 2021, 25 blaKPC-3-positive Enterobacteriale isolates were detected from 24 patients in China. Whole-genome sequencing analysis revealed that the blaKPC-3 genes were harbored by IncX8 plasmids. The outbreak involved clonal expansion of KPC-3-producing Serratia marcescens and transmission of blaKPC-3 plasmids across different species. The blaKPC-3 plasmids demonstrated high conjugation frequencies (10-3 to 10-4). A Galleria mellonella infection model showed that 2 sequence type 65 K2 K. pneumoniae strains containing blaKPC-3 plasmids were highly virulent. A ceftazidime/avibactam in vitro selection assay indicated that the KPC-3-producing strains can readily develop resistance. The spread of blaKPC-3-harboring IncX8 plasmids and these KPC-3 strains should be closely monitored in China and globally.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Carbapenémicos , China/epidemiología , Brotes de Enfermedades , Humanos , Infecciones por Klebsiella/epidemiología , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Serratia marcescens/genética , beta-Lactamasas/genética
6.
Small ; 18(14): e2106657, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35023632

RESUMEN

Mapping technique has been the powerful tool for the design of next-generation energy storage devices. Unlike the traditional ion-insertion based lithium batteries, the Li-S battery is based on the complex conversion reactions, which require more cooperation from mapping techniques to elucidate the underlying mechanism. Therefore, in this review, the representative works of mapping techniques for Li-S batteries are summarized, and categorized into the studies of lithium metal anode and sulfur cathode, with sub-sections based on shared characterization mechanisms. Due to specific features of mapping techniques, various aspects such as compositional distribution, in-plain/cross section characterization, coin cell/pouch cell configuration, and structural/mechanical analysis are emphasized in each study, aiming for the guidance for developing strategies to improve the battery performances. Benefited from the achieved progresses, suggestions for future studies based on mapping techniques are proposed to accelerate the development and commercialization of the Li-S battery.

7.
Eur Spine J ; 31(2): 473-481, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34981259

RESUMEN

PURPOSE: This study aimed to compare osteotomized debridement (OD) with traditional curetted debridement (CD) in treating thoracolumbar tuberculosis (TB). METHODS: A total of 188 patients were diagnosed with active thoracolumbar TB and underwent one-stage posterior surgery at our institution. Of the 188 patients, 85 patients were treated with OD, and 103 patients were treated with traditional CD. The patient information, laboratory results, imaging findings, and clinical effectiveness were, respectively, compared between the two groups. RESULTS: Group OD consumed less operation time and blood loss than group CD (P < 0.05 for both values). No significant difference in hospitalization time was found between the two groups (P > 0.05). The values of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) in both groups returned to the normal range within one month postoperatively. All patients had significant improvement in visual analog scale (VAS) and oswestry disability index (ODI) postoperatively. The mean fusion time in group OD was shorter than that in group CD (P < 0.05). There was no statistically significant difference in preoperative kyphotic angle between the two groups (P > 0.05), but group OD showed less correction loss than group CD at the final follow-up (P < 0.05). The rate of recurrence and surgery-related complications in group OD was lower than group CD. CONCLUSIONS: Posterior OD, reconstruction with titanium mesh cages (TMCs), and instrumentation is feasible and effective in treating thoracolumbar TB. Compared with the traditional CD, OD can achieve radical lesion removal, more effective kyphosis correction, lower recurrence rate, and fewer complications.


Asunto(s)
Fusión Vertebral , Tuberculosis de la Columna Vertebral , Desbridamiento/métodos , Humanos , Vértebras Lumbares/cirugía , Estudios Retrospectivos , Fusión Vertebral/métodos , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/cirugía , Resultado del Tratamiento , Tuberculosis de la Columna Vertebral/complicaciones , Tuberculosis de la Columna Vertebral/diagnóstico por imagen , Tuberculosis de la Columna Vertebral/cirugía
8.
BMC Genomics ; 22(1): 460, 2021 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-34147070

RESUMEN

BACKGROUND: Duplicated gene pairs produced by ancient polyploidy maintain high sequence similarity over a long period of time and may result from illegitimate recombination between homeologous chromosomes. The genomes of Asian cultivated rice Oryza sativa ssp. indica (XI) and Oryza sativa ssp. japonica (GJ) have recently been updated, providing new opportunities for investigating ongoing gene conversion events and their impact on genome evolution. RESULTS: Using comparative genomics and phylogenetic analyses, we evaluated gene conversion rates between duplicated genes produced by polyploidization 100 million years ago (mya) in GJ and XI. At least 5.19-5.77% of genes duplicated across the three rice genomes were affected by whole-gene conversion after the divergence of GJ and XI at ~ 0.4 mya, with more (7.77-9.53%) showing conversion of only portions of genes. Independently converted duplicates surviving in the genomes of different subspecies often use the same donor genes. The ongoing gene conversion frequency was higher near chromosome termini, with a single pair of homoeologous chromosomes, 11 and 12, in each rice genome being most affected. Notably, ongoing gene conversion has maintained similarity between very ancient duplicates, provided opportunities for further gene conversion, and accelerated rice divergence. Chromosome rearrangements after polyploidization are associated with ongoing gene conversion events, and they directly restrict recombination and inhibit duplicated gene conversion between homeologous regions. Furthermore, we found that the converted genes tended to have more similar expression patterns than nonconverted duplicates. Gene conversion affects biological functions associated with multiple genes, such as catalytic activity, implying opportunities for interaction among members of large gene families, such as NBS-LRR disease-resistance genes, contributing to the occurrence of the gene conversion. CONCLUSION: Duplicated genes in rice subspecies generated by grass polyploidization ~ 100 mya remain affected by gene conversion at high frequency, with important implications for the divergence of rice subspecies.


Asunto(s)
Oryza , Anciano de 80 o más Años , Evolución Molecular , Duplicación de Gen , Genes Duplicados , Genoma de Planta , Humanos , Oryza/genética , Filogenia
9.
J Cell Biochem ; 120(2): 1643-1650, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30324654

RESUMEN

Atherosclerosis has been recognized as a chronic inflammatory disease, which can harden the vessel wall and narrow the arteries. MicroRNAs exhibit crucial roles in various diseases including atherosclerosis. However, so far, the role of miR-328 in atherosclerosis remains barely explored. Therefore, our study concentrated on the potential role of miR-328 in vascular endothelial cell injury during atherosclerosis. In our current study, we observed that oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells (HUVECs) apoptosis and inhibited cell viability dose-dependently and time-dependently. In addition, indicated dosage of ox-LDL obviously triggered HUVECs inflammation and oxidative stress process. Then, it was found that miR-328 in HUVECs was reduced by ox-LDL. HUVECs apoptosis was greatly repressed and cell survival was significantly upregulated by overexpression of miR-328. Furthermore, mimics of miR-328 rescued cell inflammation and oxidative stress process induced by ox-LDL. Oppositely, inhibitors of miR-328 strongly promoted ox-LDL-induced endothelial cells injury in HUVECs. By using bioinformatics analysis, high-mobility group box-1 (HMGB1) was predicted as a downstream target of miR-328. HMGB1 has been reported to be involved in atherosclerosis development. The correlation between miR-328 and HMGB1 was validated in our current study. Taken these together, it was implied that miR-328 ameliorated ox-LDL-induced endothelial cells injury through targeting HMGB1 in atherosclerosis.

10.
Small ; 15(35): e1901980, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31267654

RESUMEN

As one important electrode reaction in electrocatalytic and photoelectrochemical cells for renewable energy circulation, oxygen catalysis has attracted considerable research in developing efficient and cost-effective catalysts. Due to the inevitable formation of oxygenic intermediates on surface sites during the complex reaction steps, the surface structure dynamically evolves toward reaction-preferred active species. To date, transition metal compounds, here defined as TM-Xides, where "X" refers to typical nonmetal elements from group IIIA to VIA, including hydroxide as well, are reported as high-performance oxygen evolution reaction (OER) electrocatalysts. However, more studies observe at least exterior oxidation or amorphization of materials. Thus, whether the TM-Xides can be defined as OER catalysts deserves further discussion. This Review pays attention to recent progress on the surface reconstruction of TM-Xide OER electrocatalysts with an emphasis on the identification of the true active species for OER, and aims at disseminating the real contributors of OER performance, especially under long-duration electrocatalysis.

11.
Angew Chem Int Ed Engl ; 58(48): 17458-17464, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31550415

RESUMEN

The oxygen evolution reaction (OER) has been explored extensively for reliable hydrogen supply to boost the energy conversion efficiency. The superior OER performance of newly developed non-noble metal electrocatalysts has concealed the identification of the real active species of the catalysts. Now, the critical active phase in nickel-based materials (represented by NiNPS) was directly identified by observing the dynamic surface reconstruction during the harsh OER process via combining in situ Raman tracking and ex situ microscopy and spectroscopy analyses. The irreversible phase transformation from NiNPS to α-Ni(OH)2 and reversible phase transition between α-Ni(OH)2 and γ-NiOOH prior to OER demonstrate γ-NiOOH as the key active species for OER. The hybrid catalyst exhibits 48-fold enhanced catalytic current at 300 mV and remarkably reduced Tafel slope to 46 mV dec-1 , indicating the greatly accelerated catalytic kinetics after surface evolution.

12.
Angew Chem Int Ed Engl ; 58(14): 4484-4502, 2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30277009

RESUMEN

Electrocatalytic water splitting is one of the most promising sustainable energy conversion technologies, but is limited by the sluggish electrochemical reactions. Inorganic nanomaterials have been widely used as efficient catalysts for promoting the electrochemical kinetics. Several approaches to optimize the activities of these nanocatalysts have been developed. The electronic structures of the catalysts play a pivotal role in governing the activity and thus have been identified as an essential descriptor. However, the underlying working mechanisms related to the refined electronic structures remain elusive. To establish the structure-electronic-behavior-activity relationship, a comprehensive overview of the developed strategies to regulate the electronic structures is presented, emphasizing the surface modification, strain, phase transition, and heterostructure. Current challenges to the fundamental understanding of electron behaviors in the nanocatalysts are fully discussed.

13.
Small ; 14(38): e1802477, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30146774

RESUMEN

Cu nanocrystals of various shapes are synthesized via a universal, eco-friendly, and facile colloidal method on Al substrates using hexadecylamine (HDA) as a capping agent and glucose as a reductant. By tuning the concentration of the capping agent, hierarchical 3D Cu nanocrystals show pronounced surface-enhanced Raman scattering (SERS) through the concentrated hot spots at the sharp tips and gaps due to the unique 3D structure and the resulting plasmonic couplings. Intriguingly, 3D sword-shaped Cu crystals have the highest enhancement factor (EF) because of their relatively uniform size distribution and alignment. This work opens new pathways for efficiently realizing morphology control for Cu nanocrystals as highly efficient SERS platforms.

14.
Arch Orthop Trauma Surg ; 137(4): 517-522, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28236185

RESUMEN

STUDY DESIGN: This is a cadaver specimen study to confirm new pedicle screw (PS) entry point and trajectory for subaxial cervical PS insertion. OBJECTIVE: To assess the accuracy of the lateral vertebral notch-referred PS insertion technique in subaxial cervical spine in cadaver cervical spine. BACKGROUNDS: Reported morphometric landmarks used to guide the surgeon in PS insertion show significant variability. In the previous study, we proposed a new technique (as called "notch-referred" technique) primarily based on coronal multiplane reconstruction images (CMRI) and cortical integrity after PS insertion in cadavers. However, the PS position in cadaveric cervical segment was not confirmed radiologically. Therefore, the difference between the pedicle trajectory and the PS trajectory using the notch-referred technique needs to be illuminated. METHODS: Twelve cadaveric cervical spines were conducted with PS insertion using the lateral vertebral notch-referred technique. The guideline for entry point and trajectory for each vertebra was established based on the morphometric data from our previous study. After 3.5-mm diameter screw insertion, each vertebra was dissected and inspected for pedicle trajectory by CT scan. The pedicle trajectory and PS trajectory were measured and compared in axial plane. The perforation rate was assessed radiologically and was graded from ideal to unacceptable: Grade 0 = screw in pedicle; Grade I = perforation of pedicle wall less than one-fourth of the screw diameter; Grade II = perforation more than one-fourth of the screw diameter but less than one-second; Grade III = perforation more than one-second outside of the screw diameter. In addition, pedicle width between the acceptable and unacceptable screws was compared. RESULTS: A total of 120 pedicle screws were inserted. The perforation rate of pedicle screws was 78.3% in grade 0 (excellent PS position), 10.0% in grade I (good PS position), 8.3% in grade II (fair PS position), and 3.3% in grade III (poor PS position). The overall accepted accuracy of pedicle screws was 96.7% (Grade 0 + Grade I + Grade II), and only 3.3% had critical breach. There was no statistical difference between the pedicle trajectory and PS trajectory (p > 0.05). Compared to the pedicle width (4.4 ± 0.7 mm) in acceptably inserted screw, the unacceptably screw is 3.2 ± 0.3 mm which was statistically different (p < 0.05). CONCLUSION: The accuracy of the notch-referred PS insertion in cadaveric subaxial cervical spine is satisfactory.


Asunto(s)
Vértebras Cervicales/cirugía , Procedimientos Ortopédicos/métodos , Tornillos Pediculares , Adulto , Tornillos Óseos , Cadáver , Vértebras Cervicales/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Modelos Anatómicos , Tomografía Computarizada por Rayos X
15.
Inorg Chem ; 54(2): 667-74, 2015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-25559416

RESUMEN

Olivine-type lithium manganese phosphate (LiMnPO4) has been considered as a promising cathode for next-generation Li-ion batteries. Preparation of high-performance LiMnPO4 still remains a great challenge because of its intrinsically low Li-ion/electronic conductivity. In this work, significant performance enhancement of LiMnPO4 has been realized by a controllable acid-engaged morphology tailoring from large spindles into small plates. We find that acidity plays a critical role in altering the morphology of the LiMnPO4 crystals. We also find that size decrease and plate-like morphology are beneficial for the performance improvement of LiMnPO4. Among the plate-like samples, the one with the smallest size shows the best electrochemical performance. After carbon coating, it can deliver high discharge capacities of 104.0 mAh g(-1) at 10 C and 85.0 mAh g(-1) at 20 C. After 200 cycles at 1 C, it can still maintain a high discharge capacity of 106.4 mAh g(-1), showing attractive applications in high-power and high-energy Li-ion batteries.

16.
mSphere ; 9(1): e0061223, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38193656

RESUMEN

The emergence of Klebsiella pneumoniae carbapenemase-2 (KPC-2) and New Delhi metallo-ß-lactamase (NDM)-coproducing hypervirulent carbapenem-resistant Klebsiella pneumoniae (KPC-2-NDM-hv-CRKP) poses a certain threat to public health. Currently, only a few sporadic reports of such double-positive hv-CRKPs were available. In this study, we isolated two KPC-2-NDM-5-hv-CRKPs from elderly patients with serious underlying diseases and poor prognoses. We found both FK3122 and FK3127 were typical multidrug-resistant (MDR) isolates, exhibiting high-level resistance to both carbapenems and novel ß-lactamase inhibitors ceftazidime/avibactam. Notably, FK3122 is even resistant to cefiderocol due to multiple blaNDM-5 elements. Besides the MDR phenotype, A549 human lung epithelial cells and Galleria mellonella infection model all indicated that FK3122 and FK3127 were highly pathogenic. According to the whole-genome sequencing analysis, we observed over 10 resistant elements, and the uncommon co-existence of blaKPC-2, blaNDM-5, and virulence plasmids in both two isolates. Both virulence plasmids identified in FK3122 and FK3127 shared a high identity with classical virulence plasmid pK2044, harboring specific hypervirulent factors: rmpA and iuc operon. We also found that the resistance and virulence plasmids in FK3127 could not only be transferred to Escherichia coli EC600 independently but also together as a co-transfer, which was additionally confirmed by the S1-pulsed-field gel electrophoresis plasmid profile. Moreover, polymorphic mobile genetic elements were found surrounding resistance genes, which may stimulate the mobilization of resistance genes and result in the duplication of these elements. Considering the combination of high pathogenicity, limited therapy options, and easy transmission of KPC-2-NDM-5-hv-CRKP, our study emphasizes the need for underscores the imperative for ongoing surveillance of these pathogens.IMPORTANCEHypervirulent Klebsiella pneumoniae drug resistance has increased gradually with the emergence of carbapenem-resistant hypervirulent K. pneumoniae (hv-CRKP). However, little information is available on the virulence characteristics of the New Delhi metallo-ß-lactamase (NDM) and Klebsiella pneumoniae carbapenemase-2 (KPC-2) co-producing K. pneumoniae strains. In this study, we obtained two KPC-2-NDM-hv-CRKPs from elderly patients, each with distinct capsule types and sequence types: ST11-KL64 and ST15-KL24; these ST-type lineages are recognized as classical multidrug-resistant (MDR) K. pneumoniae. We found these KPC-2-NDM-hv-CRKPs were not only typical MDR isolates, including resistance to ceftazidime/avibactam and cefiderocol, but also displayed exceptionally high levels of pathogenicity. In addition, these high-risk factors can also be transferred to other isolates. Consequently, our study underscores the need for ongoing surveillance of these isolates due to their heightened pathogenicity, limited therapeutic options, and potential for easy transmission.


Asunto(s)
Compuestos de Azabiciclo , Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella , Humanos , Anciano , Ceftazidima/farmacología , Klebsiella pneumoniae , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones por Klebsiella/epidemiología , Carbapenémicos/farmacología , Escherichia coli/genética
17.
Infect Drug Resist ; 17: 2541-2554, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38933778

RESUMEN

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections are a great threat to public health worldwide. Ceftazidime-avibactam (CZA) is an effective ß-lactam/ß-lactamase inhibitors against CRKP. However, reports of resistance to CZA, mainly caused by Klebsiella pneumoniae carbapenemase (KPC) variants, have increased in recent years. In this study, we aimed to describe the resistance characteristics of KPC-12, a novel KPC variant identified from a CZA resistant K. pneumoniae. Methods: The K. pneumoniae YFKP-97 collected from a patient with respiratory tract infection was performed whole-genome sequencing (WGS) on the Illumina NovaSeq 6000 platform. Genomic characteristics were analyzed using bioinformatics methods. Antimicrobial susceptibility testing was conducted by the broth microdilution method. Induction of resistant strain was carried out in vitro as previously described. The G. mellonella killing assay was used to evaluate the pathogenicity of strains, and the conjugation experiment was performed to evaluate plasmid transfer ability. Results: Strain YFKP-97 was a multidrug-resistant clinical ST11-KL47 K. pneumoniae confers high-level resistance to CZA (16/4 µg/mL). WGS revealed that a KPC variant, KPC-12, was carried by the IncFII (pHN7A8) plasmids (pYFKP-97_a and pYFKP-97_b) and showed significantly decreased activity against carbapenems. In addition, there was a dose-dependent effect of bla KPC-12 on its activity against ceftazidime. In vitro inducible resistance assay results demonstrated that the KPC-12 variant was more likely to confer resistance to CZA than the KPC-2 and KPC-3 variants. Discussion: Our study revealed that patients who was not treated with CZA are also possible to be infected with CZA-resistant strains harbored a novel KPC variant. Given that the transformant carrying bla KPC-12 was more likely to exhibit a CZA-resistance phenotype. Therefore, it is important to accurately identify the KPC variants as early as possible.

18.
Anticancer Res ; 43(7): 3037-3046, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37351956

RESUMEN

BACKGROUND/AIM: The present study aimed to identify key long noncoding RNAs (lncRNAs) involved in survival and metastasis of clear cell renal cell carcinoma (ccRCC). MATERIALS AND METHODS: A systemic screening for genes with differential expression in ccRCC was performed using publicly available databases. Cox regression analysis was used to identify lncRNAs associated with survival. A competing endogenous RNAs (ceRNA) regulation network of metastasis-related lncRNAs was constructed and hub lncRNAs were identified. Functional and pathway enrichment analyses were performed to investigate the role of lncRNA in ccRCC. Cell Counting Kit-8 and Transwell assays were used to determine the levels of cell proliferation, migration, and invasion. RESULTS: A total of 732 lncRNAs were found to be differentially expressed between ccRCC tumors and healthy samples. Among them, 139 lncRNAs were differentially expressed between metastasis and non-metastasis ccRCC samples and 75 lncRNAs were associated with overall survival and curated metastasis-related genes. Notably, LINC01480 was identified as the hub lncRNA involved in regulation of ccRCC metastasis. Clinically, LINC01480 may act as an independent factor for poor overall survival of ccRCC patients (log-rank p<0.05). Reverse transcription-quantitative PCR analysis validated that LINC01480 was significantly up-regulated in ccRCC compared to paired normal samples (n=20). Moreover, LINC01480 silencing inhibited the proliferation, migration, and invasion of ccRCC cells in vitro. Gene set enrichment analysis showed that high LINC01480 expression may promote ccRCC metastasis through enhancing immunodeficiency and amino acid metabolism. CONCLUSION: LINC01480 may act as a novel biomarker for overall prognosis in ccRCC and exhibit potential as a therapeutic target for the treatment of metastatic ccRCC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , ARN Largo no Codificante , Humanos , Carcinoma de Células Renales/patología , Neoplasias Renales/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Pronóstico , Línea Celular Tumoral , Proliferación Celular/genética
19.
Materials (Basel) ; 16(8)2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37110007

RESUMEN

Water electrolysis as an important and facile strategy to generate hydrogen has attracted great attention, and efficient electrocatalysts play a key role in hydrogen evolution reaction (HER). Herein, vertical graphene (VG)-supported ultrafine NiMo alloy nanoparticles (NiMo@VG@CC) were fabricated successfully via electro-depositing as efficient self-supported electrocatalysts for HER. The introduction of metal Mo optimized the catalytic activity of transition metal Ni. In addition, VG arrays as the three-dimensional (3D) conductive scaffold not only ensured high electron conductivity and robust structural stability, but also endowed the self-supported electrode large specific surface area and exposed more active sites. With the synergistic effect between NiMo alloys and VG, the optimized NiMo@VG@CC electrode exhibited a low overpotential of 70.95 mV at 10 mA cm-2 and a remarkable stable performance over 24 h. This research is anticipated to offer a powerful strategy for the fabrication of high-performance hydrogen evolution catalysts.

20.
Infect Drug Resist ; 16: 403-411, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36718464

RESUMEN

Background: Patients with neurological disorders were easier to develop severe intracranial infections caused by hypervirulent and carbapenem-resistant K. pneumoniae, leading to a distressing clinical outcome. In this study, eight hv-CRKP were isolated from neurological patients, to clarify the resistant and virulent features. Methods: We tested the susceptibility of common antibiotics in these isolates to feature the antibiotic-resistant phenotypes. We also detected the key virulence factors, including mucoviscosity, siderophores production, biofilm formation in vitro, and further evaluated the virulence potential with serum killing model. We also used whole-genome sequencing (WGS) to investigate the molecular mechanisms. Results: We observed that ST11-KL64 hv-CRKP (6/8) has an overwhelming epidemic dominance in these hypervirulent and carbapenem-resistant K. pneumoniae. Though the acquirement of virulence plasmid made no influence to the maintain of multidrug-resistant phenotype of these isolates, only the ST11-KL64 strains fully exhibited the hypervirulent features. Compared with ST11-KL47 and ST15-KL24 strains, ST11-KL64 hv-CRKP were more advantages in productions of capsule polysaccharide, biofilm, and siderophores. The virulence potential of ST11-KL64 hv-CRKP was further confirmed by using serum killing model. Previous studies have demonstrated that IncFII plasmid could act as a helper plasmid to mobile the non-conjugative IncFIB/IncHIB virulence plasmids. We could only observe the co-existence of IncFII resistance plasmid and IncFIB/IncHIB virulence plasmids in ST11-KL64 isolates. The co-existence of such two plasmids facilitated the formation of ST11-KL64 hv-CPKP, which then become nosocomial epidemic under the antibiotic stress. Conclusion: Overall, we observed the ST11-KL64 hv-CRKP dominated in the isolates from neurological patients, and required most clinical attention.

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