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We further mapped our genome to the p17-84 OXA plasmid (accession number: CP059478) (Figure 1B), which is located in an ST63 pandrug-resistant I A. pittii i .[15] High nucleotide sequence identity was observed for some of the contigs in the TCM2 genome with p17-84 OXA (Figure 1C). Identified resistance genes were correlated with the actual antimicrobial resistance phenotype of the strain and a I bla i SB OXA-58 sb -bearing plasmid should be harbored by the TCM2 strain. Consequently, we concluded that there was a I bla i SB OXA-58 sb -bearing plasmid in the TCM2 strain, which was probably obtained from other I A. pittii i and I A. nosocomialis i strains collected in China in 2012 and 2014, respectively (Supplementary Table 2). [Extracted from the article]

The clinical responses to the EGFR kinase inhibitors in non-small cell lung cancer (NSCLC) patients are always followed by drug-resistance mutations, including the gatekeeper T790M mutation. Strategies targeting EGFRT790M are also limited by the toxicity due to the concurrent inhibition of wide-type (WT) EGFR. Here we employed splicing principle to design and synthesize a series of aminopyrimidine derivatives bearing dihydroquinoxalinone (8–15) as novel third-generation inhibitors against double mutant L858R/T790M in EGFR. It is worth noting that compound 10 presented remarkable inhibitory activity against EGFRL858R/T790M (IC50 = 15 ± 1.8 nM) and anti-proliferative effect against H1975 cells (IC50 = 166.43 ± 14.45 nM). Moreover, the obvious down-regulation effect of EGFR-mediated signaling pathways and the promotion of apoptosis in H1975 cells confirmed its potent efficacy. These results demonstrated that compound 10 deserves the further exploration. [ABSTRACT FROM AUTHOR]

Background. Triple-negative breast cancer (TNBC) is a subtype of breast cancer with limited therapeutic options. Eupalinolide O (EO) was reported to inhibit tumor growth. This study is aimed at exploring the role of EO on TNBC both in vivo and in vitro. Methods. In in vitro experiments, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clonogenic assay were conducted to measure the impact of EO on TNBC cell growth at different concentrations and time points. Flow cytometry was conducted to evaluate cell apoptosis. Mitochondrial membrane potential (MMP) loss, caspase-3 activity, and reactive oxygen species (ROS) generation were assessed. The expressions of apoptosis-related mRNAs and Akt/p38 MAPK signaling pathway-related proteins were measured. In in vivo experiments, by injecting TNBC cells into the nude mice to induce xenograft tumor, mice were treated with EO for 20 days. Then, in vivo bioluminescence imaging system was utilized to monitor the growth and distribution of TNBC cells. Tumor volume and weight were also recorded. Hematoxylin-eosin (HE) staining and ELISA assay were applied to observe tumor tissue morphology and ROS levels. Furthermore, western blotting was conducted to observe the expression of apoptosis-related proteins and Akt/p38 MAPK signaling pathway-associated proteins. Results. EO inhibited the cell viability and proliferation of TNBC cells but not normal epithelial cells. Furthermore, EO induced apoptosis, decreased MMP, and elevated caspase-3 activity and ROS content in TNBC cells. Meanwhile, the expression of apoptosis-related mRNAs and Akt/p38 MAPK pathway-related proteins was regulated by EO treatment. Besides, in vivo experiments demonstrated EO not only suppressed tumor growth, Ki67 expression, ROS generation, and Akt phosphorylation but also upregulated caspase-3 expression and p-38 phosphorylation. Conclusion. EO may induce cell apoptosis in TNBC via regulating ROS generation and Akt/p38 MAPK pathway, indicating EO may be a candidate drug for TNBC. [ABSTRACT FROM AUTHOR]

An efficient synthesis of indolizines with a thioether group is developed through employing [4+2]-annulation of N-substituted pyrrole-2-carboxaldehydes and prop-2-ynylsulfonium salts, forming a wide variety of target compounds with various substituents and functionalities in moderate to good yields. The success of this transformation makes it an alternative approach to previous protocols, and pharmaceutical and biomedical applications of the investigated compounds are expected with further development. [ABSTRACT FROM AUTHOR]

Lead (Pb) is an important environmental pollutant. Oxidative stress and the inflammatory response have been postulated as mechanisms involved in lead-induced renal damage. Smilax glabra Roxb. has been used for treatment of heavy-metal poisoning in China for 500 years. We investigated S. glabra flavonoids extract (SGF) could attenuate lead acetate-induced nephrotoxicity in weaning rats and human embryonic kidney (HEK)-293 cells, and investigated the possible mechanisms. Compared with Pb exposed group of weaning rats, SGF could significantly promote lead excretion in the blood and kidney, and increase the content of the renal-function indicators blood urea nitrogen, serum uric acid, and serum creatinine. SGF could improve the glomerular filtration rate (GFR) and histologic changes in the kidneys of weaning rats exposed to Pb. SGF could also reduce lead-induced cytotoxicity, improve DNA damage-induced apoptosis and cleaved caspase-3-mediated apoptosis in HEK-293 cells stimulated with Pb. SGF significantly increased the activity of the antioxidant enzymes superoxide dismutase, glutathione peroxidase and catalase, and decreased excessive release of reactive oxygen species (ROS) and malondialdehyde in the kidneys of the weaning rats and in HEK-293 cells. The antioxidant mechanism of SGF related to activation of the Kelch-like ECH-associated protein 1/nuclear-factor-E2-related factor 2/hemeoxygenase-1(Keap1/Nrf2/HO-1) pathway. SGF could inhibit secretion of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α induced by Pb in vivo and in vitro. The anti-inflammatory mechanism of SGF related to inhibition of ROS and pro-inflammatory cytokines triggered the nuclear factor-kappa B (NF-κB) pathway through blockade of inhibitors of I-κB degradation, phosphorylation of NF-κB p65, and nuclear translocation of p65. Our findings indicate that SGF could be a natural antioxidant and anti-inflammatory agent for treating lead-induced nephrotoxicity. [ABSTRACT FROM AUTHOR]

Hypervirulent carbapenem-resistant Klebsiella pneumoniae (hv-CRKP) has been widely reported and poses a global threat. However, the comprehensive genetic structure of ST11-KL64 hv-CRKP and the possible evolutionary mechanisms from a genetic structure perspective of this high-risk clone remain unclear. Here, a bla KPC-2 - bla NDM-1 -positive ST11-KL64 hv-CRKP isolate was obtained from a human bloodstream infection (BSI). Whole-genome sequencing and bioinformatics analyses revealed that it contained a fusion plasmid, pKPTCM2–1. pKPTCM2–1 is a conjugative plasmid composed of an oriT -positive pLVPK-like virulence plasmid and a type IV secretion system-produced bla NDM-1 -bearing IncX3 plasmid mediated by IS 26 -based co-integration. This progress generated 8-bp target site duplications (TGAAAACC) on both sides. The fusion plasmid possessed self-transferability and could be transferred to bla KPC-2 -harboring ST11-KL64 CRKP to form the ST11-KL64 hv-CRKP clone. The pLVPK-like-positive ST11-KL64 strain exhibited virulence levels similar to those of the typical hypervirulent K. pneumoniae NTUH-2044. The mutation, Tet(A) (A276S), which was believed to lead to tigecycline resistance was observed. Overall, this high-risk clone has emerged as a tremendous threat in fatal BSIs and thus, targeted surveillance is an urgent need to contain the hv-CRKP clones. • One bla KPC-2 - bla NDM-1 -positive ST11-KL64 hv-CRKP in human bloodstream infection. • oriT -positive pLVPK-like virulence plasmid and bla NDM-1 -bearing IncX3 plasmid fusion. • One mutation of Tet(A) (A276S) maybe lead to tigecycline resistance. [ABSTRACT FROM AUTHOR]

This study aimed to isolate, prepare and identify the main flavonoids from a standardized Smilax glabra flavonoids extract (SGF) using preparative HPLC, MS, 1H NMR and 13C NMR, determine the contents of these flavonoids using UPLC, then compare their pharmacological activities in vitro. We obtained six flavonoids from SGF: astilbin (18.10%), neoastilbin (11.04%), isoastilbin (5.03%), neoisoastilbin (4.09%), engeletin (2.58%) and (−)-epicatechin (1.77%). The antioxidant activity of six flavonoids were evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2′-Azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS+) radical scavenging activity and ferric reducing antioxidant power (FRAP). In addition, the anti-inflammatory activity of six flavonoids were evaluated by determining the production of cytokines (IL-1β, IL-6), nitric oxide (NO) using enzyme linked immunosorbent assay and the NF-κB p65 expression using Western blotting in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results showed that (−)-epicatechin, astilbin, neoastilbin, isoastilbin and neoisoastilbin had strong antioxidant activities, not only in DPPH and ABTS+ radicals scavenging capacities, but in FRAP system. Furthermore, all the six flavonoids could significantly inhibit the secretion of IL-1β, IL-6, NO (p < 0.01) and the protein expression of NF-κB p-p65 (p < 0.01) in LPS-stimulated RAW264.7 cells. This study preliminarily verified the antioxidant and anti-inflammatory activities of six flavonoids in S. glabra. [ABSTRACT FROM AUTHOR]

Competing Interests: The authors report no conflicts of interest in this work.

The emergence of carbapenemase-producing Acinetobacter spp. has been widely reported and become a global threat. However, carbapenem-resistant A. johnsonii strains are relatively rare and without comprehensive genetic structure analysis, especially for isolates collected from human specimen. Here, one A. johnsonii AYTCM strain, co-producing NDM-1, OXA-58, and PER-1 enzymes, was isolated from sputum in China in 2018. Antimicrobial susceptibility testing showed that it was resistant to meropenem, imipenem, ceftazidime, ciprofloxacin, and cefoperazone/sulbactam. Whole-genome sequencing and bioinformatic analysis revealed that it possessed 11 plasmids. bla OXA-58 and bla PER-1 genes were located in the pAYTCM-1 plasmid. Especially, a complex class 1 integron consisted of a 5' conserved segment (5' CS) and 3' CS, which was found to carry sul1, arr-3, qnrVC6 , and bla PER-1 cassettes. Moreover, the bla NDM-1 gene was located in 41,087 conjugative plasmids and was quite stable even after 70 passages under antibiotics-free conditions. In addition, six prophage regions were identified. Tracking of closely related plasmids in the public database showed that pAYTCM-1 was similar to pXBB1-9, pOXA23&#95;010062, pOXA58&#95;010030, and pAcsw19-2 plasmids, which were collected from the strains of sewage in China. Concerning the pAYTCM-3 plasmids, results showed that strains were collected from different sources and their hosts were isolated from various countries, such as China, USA, Japan, Brazil, and Mexico, suggesting that a wide spread occurred all over the world. In conclusion, early surveillance is warranted to avoid the extensive spread of this high-risk clone in the healthcare setting., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Tian, Song, Ren, Huang, Wang, Fu, Zhao, Bai, Fan, Ma and Ying.)

Objectives: To characterize one OXA-232-producing wzi93 -KL112-O1 carbapenem-resistant Klebsiella pneumoniae (CRKP) co-harboring chromosomal bla CTX-M-15 and one rmpA2 -associated virulence plasmid., Methods: Minimum inhibitory concentrations (MICs) were measured via broth microdilution method. Conjugation, chemical transformation, string test and Galleria mellonella infection model experiments were also conducted. Whole-genome sequencing (WGS) was performed on the Illumina and Nanopore platforms. Antimicrobial resistance determinants were identified using ABRicate program with ResFinder database. Insertion sequences (ISs) were identified using ISfinder. Bacterial virulence factors were identified using virulence factor database (VFDB). Wzi, capsular polysaccharide (KL) and lipoolygosaccharide (OCL) were analyzed using Kleborate with Kaptive . Phylogenetic analysis of 109 ST15 K. pneumoniae strains was performed using core genome multilocus sequence typing (cgMLST) on the Ridom SeqSphere+ server. MLST, replicons type, SNP strategies and another cgMLST analysis for 45 OXA-232-producing K. pneumoniae strains were further conducted using BacWGSTdb server., Results: K. pneumoniae KPTCM strain belongs to ST15 with wzi93 , KL112 and O1. It possessed a multidrug-resistant (MDR) profile and was resistant to carbapenems (meropenem and ertapenem), ciprofloxacin and amikacin. Virulence assays demonstrated KPTCM strain possesses a low virulence phenotype. WGS revealed it contained one circular chromosome and nine plasmids. The carbapenemase-encoding gene bla OXA-232 was located in a 6141-bp ColKP3-type non-conjugative plasmid and flanked by ΔIS Ecp1 and Δ lysR -Δ ereA . Interestingly, bla CTX-M-15 was located in the chromosome mediated by IS Ecp1- based transposon Tn 2012 . Importantly, it harbored a rmpA2 -associated pLVPK-like virulence plasmid with iutA - iucABCD gene cluster and one IS 26 -mediated MDR fusion plasmid according to 8-bp (AGCTGCAC or GGCCTTTG) target site duplications (TSD). Based on the cgMLST and SNP analysis, data showed OXA-232-producing ST15 K. pneumoniae isolates were mainly isolated from China and have evolved in recent years., Conclusions: Early detection of CRKP strains carrying chromosomal bla CTX-M-15 , OXA-232 carbapenemase and pLVPK-like virulence plasmid is recommended to avoid the extensive spread of this high-risk clone., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tian, Xing, Zhao, Fan, Bai, Fu and Wang.)

Objective: To characterize one KL38-OCL6-ST220 carbapenem-resistant Acinetobacter pittii strain, co-producing chromosomal NDM-1 and OXA-820 carbapenemases., Methods: A. pittii TCM strain was isolated from a bloodstream infection (BSI). Antimicrobial susceptibility tests were conducted via disc diffusion and broth microdilution. Stability experiments of bla NDM-1 and bla OXA-820 carbapenemase genes were further performed. Whole-genome sequencing (WGS) was performed on the Illumina and Oxford Nanopore platforms. Multilocus sequence typing (MLST) was analyzed based on the Pasteur and Oxford schemes. Resistance genes, virulence factors, and insertion sequences (ISs) were identified with ABRicate based on ResFinder 4.0, virulence factor database (VFDB), and ISfinder. Capsular polysaccharide (KL), lipooligosaccharide outer core (OCL), and plasmid reconstruction were tested using Kaptive and PLACNETw. PHASTER was used to predict prophage regions. A comparative genomics analysis of all ST220 A. pittii strains from the public database was carried out. Point mutations, average nucleotide identity (ANI), DNA-DNA hybridization (DDH) distances, and pan-genome analysis were performed., Results: A. pittii TCM was ST220 Pas and ST1818 Oxf with KL38 and OCL6, respectively. It was resistant to imipenem, meropenem, and ciprofloxacin but still susceptible to amikacin, colistin, and tigecycline. WGS revealed that A. pittii TCM contained one circular chromosome and four plasmids. The Tn 125 composite transposon, including bla NDM-1 , was located in the chromosome with 3-bp target site duplications (TSDs). Many virulence factors and the bla OXA-820 carbapenemase gene were also identified. The stability assays revealed that bla NDM-1 and bla OXA-820 were stabilized by passage in an antibiotic-free medium. Moreover, 12 prophage regions were identified in the chromosome. Phylogenetic analysis showed that there are 11 ST220 A. pittii strains, and one collected from Anhui, China was closely related. All ST220 A. pittii strains presented high ANI and DDH values; they ranged from 99.85% to 100% for ANI and from 97.4% to 99.9% for DDH. Pan-genome analysis revealed 3,200 core genes, 0 soft core genes, 1,571 shell genes, and 933 cloud genes among the 11 ST220 A. pittii strains., Conclusions: The coexistence of chromosomal NDM-1 and OXA-820 carbapenemases in A. pittii presents a huge challenge in healthcare settings. Increased surveillance of this species in hospital and community settings is urgently needed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tian, Xing, Fu, Zhao, Fan and Wang.)