Purpose The main objectives of the present study were to detect the antimicrobial susceptibility and molecular characteristics of Klebsiella pneumoniae isolated from different hosts and to investigate the possibility of K. pneumoniae transmission between animals and humans. Materials and methods A total of 189 nonduplicate K. pneumoniae isolates were collected from hospitals and four species of animals in Henan Province, China. The disk diffusion method was used for antimicrobial susceptibility testing, and resistance and virulence genes were screened by polymerase chain reaction (PCR). The molecular types were identified through multilocus sequence typing (MLST), and the hypermucoviscous (HMV) phenotype was identified using the “string-forming test”. Pearson’s parameters were used to determine the potential link among the molecular types and resistance and virulence genes of all K. pneumoniae strains. Results The resistance rates of the 189 K. pneumoniae isolates against 15 antibiotics ranged from 11.6% to 77.8%. The highest multidrug resistance rate was detected in the pig strains (93.6%), followed by the human strains (90.4%), chicken strains (88.9%), cow strains (52.0%) and sheep strains (50.0%). Forty-eight (25.4%) K. pneumoniae strains presented the HMV phenotype. entB, fimH-1 and mrkD were the most prevalent of the detected virulence genes, and magA and rmpA were the least prevalent genes in all the isolates. The MLST analysis revealed 24 unique sequence types (STs) among from the 189 isolates. ST11, ST235 and ST258 were common STs among the five isolates of host origin. ST258 exhibited significantly positive correlations with blaNDM, magA and the HMV phenotype and a negative correlation with qnrB . Conclusion K. pneumoniae strains from different hosts, including humans and animals, have common molecular types and similar phenotypes, and these strains can potentially be transmitted between humans and animals.

We investigate theoretically the transport properties of surface plasmon in a metal nanowire with linear and nonlinear dispersion relations coupled to a quantum dot with three levels in cascaded configuration by full quantum-mechanical approach. The transmission and reflection amplitudes are obtained. The reflection spectrum shows two peaks for the surface plasmon with linear dispersion relation while it can exhibit four peaks when the plasmon has quadratic dispersion relation. The calculations reveal that one can control the plasmon transport properties by adjusting Rabi frequency and circular frequency of a classic optical field.

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We investigate theoretically entanglement generation between two distant quantum dot molecules (QDMs) mediated by quantum bus of metal nanoring with surface plasmon polaritons. We show that the two QDMs can be in an entangled state by adjusting the external gate voltage and the coupling strength between the QDMs and the surface plasmon polaritons. The quantum state transfer between the two QDMs is also discussed. Our scheme may find applications in on-chip quantum networks and integrated optoelectronics devices.

Epidermal growth factor receptor (EGFR) and insulin-like growth factor 1 receptor (IGF-1R) both overexpressed on non-small cell lung cancer (NSCLC) and are known cooperatively to promote tumor progression and drug resistance. This study was to construct a novel bispecific fusion protein EGF-IGF-LDP-AE consisting of EGFR and IGF-IR specific ligands (EGF and IGF-1) and lidamycin, an enediyne antibiotic with potent antitumor activity, and investigate its antitumor efficacy against NSCLC. Binding and internalization assays showed that EGF-IGF-LDP protein could bind to NSCLC cells with high affinity and then internalized into cells with higher efficiency than that of monospecific proteins. In vitro, the enediyne-energized analogue of bispecific fusion protein (EGF-IGF-LDP-AE) displayed extremely potent cytotoxicity to NSCLC cell lines with IC50<10−11 mol/L. Moreover, the bispecific protein EGF-IGF-LDP-AE was more cytotoxic than monospecific proteins (EGF-LDP-AE and LDP-IGF-AE) and lidamycin. In vivo, EGF-IGF-LDP-AE markedly inhibited the growth of A549 xenografts, and the efficacy was more potent than that of lidamycin and monospecific counterparts. EGF-IGF-LDP-AE caused significant cell cycle arrest and it also induced cell apoptosis in a dosage-dependent manner. Pretreatment with EGF-IGF-LDP-AE inhibited EGF-, IGF-stimulated EGFR and IGF-1R phosphorylation, and blocked two main downstream signaling molecules AKT and ERK activation. These data suggested that EGF-LDP-IGF-AE protein would be a promising targeted agent for NSCLC patients with EGFR and/or IGF-1R overexpression.