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Radiotherapy requires the target area and the organs at risk to be contoured on the CT image of the patient. During the process of organs-at-Risk (OAR) of the chest and abdomen, the doctor needs to contour at each CT image. The delineations of large and varied shapes are time-consuming and laborious. This study aims to evaluate the results of two automatic contouring softwares on OARs definition of CT images of lung cancer and rectal cancer patients. The CT images of 15 patients with rectal cancer and 15 patients with lung cancer were selected separately, and the organs at risk were manually contoured by experienced physicians as reference structures. And then the same datasets were automatically contoured based on AiContour (version 3.1.8.0, Manufactured by Linking MED, Beijing, China) and Raystation (version 4.7.5.4, Manufactured by Raysearch, Stockholm, Sweden) respectively. Deep learning auto-segmentations and Atlas were respectively performed with AiContour and Raystation. Overlap index (OI), Dice similarity index (DSC) and Volume difference (Dv) were evaluated based on the auto-contours, and independent-sample t-test analysis is applied to the results. The results of deep learning auto-segmentations on OI and DSC were better than that of Atlas with statistical difference. There was no significant difference in Dv between the results of two software. With deep learning auto-segmentations, auto-contouring results of most organs in the chest and abdomen are good, and with slight modification, it can meet the clinical requirements for planning. With Atlas, auto-contouring results in most OAR is not as good as deep learning auto-segmentations, and only the auto-contouring results of some organs can be used clinically after modification.

This study aimed to genetically characterize two fully-sequenced novel IncFII-type multidrug resistant (MDR) plasmids, p0716-KPC and p12181-KPC, recovered from two different clinical Klebsiella pneumoniae isolates. p0716-KPC and p12181-KPC had a very similar genomic content. The backbones of p0716-KPC/p12181-KPC contained two different replicons (belonging to a novel IncFII subtype and the Rep_3 family), the IncFIIK and IncFIIY maintenance regions, and conjugal transfer gene sets from IncFIIK-type plasmids and unknown origins. p0716-KPC and p12181-KPC carried similar three accessory resistance regions, namely ΔTn6209, a MDR region, and the blaKPC-2 region. Resistance genes blaKPC-2, mph(A), strAB, aacC2, qacEΔ1, sul1, sul2, and dfrA25, which are associated with transposons, integrons, and insertion sequence-based mobile units, were located in these accessory regions. p0716-KPC carried two additional resistance genes: aphA1a and blaTEM-1. Together, our analyses showed that p0716-KPC and p12181-KPC belong to a novel IncFII subtype and display a complex chimeric nature, and that the carbapenem resistance gene blaKPC-2 coexists with a lot of additional resistance genes on these two plasmids.

Invasive species may change the life history strategies, distribution, genetic configuration and trophic interactions of native species. The diamondback moth, Plutella xylostella L., is an invasive herbivore attacking cultivated and wild brassica plants worldwide. Here we present phylogeographic analyses of P. xylostella and one of its major parasitoids, Cotesia vestalis, using mitochondrial markers, revealing the genetic diversity and evolutionary history of these two species. We find evidence that C. vestalis originated in Southwest China, then adapted to P. xylostella as a new host by ecological sorting as P. xylostella expanded its geographic range into this region. Associated with the expansion of P. xylostella, Wolbachia symbionts were introduced into local populations of the parasitoid through horizontal transfer from its newly associated host. Insights into the evolutionary history and phylogeographic system of the herbivore and its parasitoid provide an important basis for better understanding the impacts of biological invasion on genetic configuration of local species.

We previously reported the complete sequence of the resistance plasmid pP10164-NDM, harboring blaNDM (conferring carbapenem resistance) and bleMBL (conferring bleomycin resistance), which is recovered from a clinical Leclercia adecarboxylata isolate P10164 from China. This follow-up work disclosed that there were still two multidrug-resistant (MDR) plasmids pP10164-2 and pP10164-3 coexisting in this strain. pP10164-2 and pP10164-3 were completely sequenced and shown to carry a wealth of resistance genes, which encoded the resistance to at least 10 classes of antibiotics (β-lactams. macrolides, quinolones, aminoglycosides, tetracyclines, amphenicols, quaternary ammonium compounds, sulphonamides, trimethoprim and rifampicin) and 7 kinds of heavy mental (mercury, silver, copper, nickel, chromate, arsenic and tellurium). All of these antibiotic resistance genes are associated with mobile elements such as transposons, integrons and insertion sequence-based transposable units, constituting a total of three novel MDR regions, two in pP10164-2 and the other one in pP10164-3. Coexistence of three resistance plasmids pP10164-NDM, pP10164-2 and pP10164-3 makes L. adecarboxylata P10164 tend to become extensively drug-resistant.

A total of 26 blaIMP-4-carrying strains of Pseudomonas aeruginosa and Klebsiella pneumoniae were isolated from 2009 to 2013 in a Chinese teaching hospital, and these strains can be assigned into multiple sequence types or allelic profiles as determined by multilocus sequence typing. Of these strains, P. aeruginosa P378 and K. pneumoniae 1220 harbor the IMP-4-encoding plasmids pP378-IMP and p1220-IMP, respectively, whose complete nucleotide sequences are determined to be genetically closely related to the IncN1-type plasmid pIMP-HZ1. pP378-IMP/p1220-IMP-like plasmids are hinted to be present in all the other blaIMP-4-carrying strains, indicating the dissemination of pIMP-HZ1-related plasmids among K. pneumoniae or P. aeruginosa of different genotypes in this hospital. pP378-IMP carries two distinct accessory resistance regions, a blaIMP-4-carrying class 1 integron In823b, and a truncated Tn3-family unit transposon ΔTn6292-3′ harboring the quinolone resistance gene qnrS1. Massive fragmentation and rearrangement of these accessory genetic contents occur among p1220-IMP and IMP-HZ1 relative to pP378-IMP. blaIMP-4 is also present in the In823b remnants from p1220-IMP and IMP-HZ1, while qnrS1 is located in a Tn6292-derive fragment from pIMP-HZ1 but not found in p1220-IMP. pP378-IMP represents the first fully sequenced IncN-type plasmid from P. aeruginosa.

Hand, foot and mouth disease (HFMD) is a common childhood illness caused by enteroviruses. HFMD outbreaks and reported cases have sharply increased in China since 2008. Epidemiological and clinical data of HFMD cases reported in Henan Province were collected from 2008 to 2013. Clinical specimens were obtained from a subset of these cases. Descriptive epidemiological methods were used to analyze the time, region and population distribution. The VP1 gene from EV71 and CA16 isolates was amplified and the sequences were analyzed. 400,264 cases of HFMD were reported in this study, including 22,309 severe and 141 fatal cases. Incidence peaked between April and May. Laboratory confirmation was obtained for 27,692 (6.9%) cases; EV71, CA16 and other enteroviruses accounted for 59.5%, 14.1%, 26.4%, respectively. Phylogenetic analysis revealed that EV71 belonged to the C4a evolution branch of C4 sub-genotype and CA16 belonged to subtype B1a or B1b. The occurrence of HFMD in Henan was closely related to season, age and region distribution. Children under five were the most affected population. The major pathogens causing HFMD and their genotypes have not notably changed in Henan. The data strongly support the importance of EV71 vaccination in a high population density area such as Henan, China.