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The dissemination of Klebsiella pneumoniae carbapenemases (KPCs) among Gram-negative bacteria is an important threat to global health. However, KPC-producing bacteria from environmental samples are rarely reported. This study aimed to elucidate the underlying resistance mechanisms of three carbapenem-resistant Aeromonas taiwanensis isolates recovered from river sediment samples. Pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS) analysis indicated a close evolutionary relationship among A. taiwanensis isolates. S1-PFGE, Southern blot and conjugation assays confirmed the presence of bla KPC–2 and qnrS2 genes on a non-conjugative plasmid in these isolates. Plasmid analysis further showed that pKPC-1713 is an IncP-6 plasmid with a length of 53,205 bp, which can be transformed into DH5α strain and mediated carbapenems and quinolones resistance. The plasmid backbone of p1713-KPC demonstrated 99% sequence identity to that of IncP-6-type plasmid pKPC-cd17 from Aeromonas spp. and IncP-6-type plasmid: 1 from Citrobacter freundii at 74% coverage. A 14,808 bp insertion sequence was observed between merT gene and hypothetical protein in p1713-KPC, which include the quinolone resistance qnrS2 gene. Emergence of plasmid-borned bla KPC and qnrS2 genes from A. taiwanensis isolates highlights their possible dissemination into the environment. Therefore, potential detection of such plasmids from clinical isolates should be closely monitored. [ABSTRACT FROM AUTHOR]

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Aiming at solving the existing issues in purity identification of Cucurbita moschata hybrids by SSR, such as complex operation and difficult application in production practice, in this study, a simple SSR-based method was established for purity identification of Cucurbita moschata hybrids. By using the established simple method, without grinding, freezing, centrifugation and drying, the genomic DNA extraction process is shorter than 3 min. compared with the conventional method, PCR detection system and silver staining in polyacrylamide gel electrophoresis of the established method are more time-saving and cost-saving. The whole detection process is shorter than 4 h, and 480 samples can be detected with this method by one person in one day. In addition, the detection result exhibits a coincidence rate of 99% with field identification. The simple SSR-based method established in this study can provide basis for large-scale rapid purity identification of Cucurbita moschata hybrids. [ABSTRACT FROM AUTHOR]

Background: Chrysomya megacephala (Fabricius), a prevalent necrophagous blowfly that is easily mass reared, is noted for being a mechanical vector of pathogenic microorganisms, a pollinator of numerous crops, and a resource insect in forensic investigation in the postmortem interval. In the present study, in order to comprehensively understand the physiological and biochemical functions of C. megacephala, we performed RNA-sequencing and digital gene expression (DGE) profiling using Solexa/Illumina sequencing technology. Methodology/Principal Findings: A total of 39,098,662 clean reads were assembled into 27,588 unigenes with a mean length of 768 nt. All unigenes were searched against the Nt database, Nr database, Swiss-Prot, Cluster of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genome (KEGG) with the BLASTn or BLASTx algorithm (E-value<0.00001) for annotations. In total, 7,081 unigenes and 14,099 unigenes were functionally classified into 25 COG categories and 240 KEGG pathways, respectively. Furthermore, 20,216 unigenes were grouped into 48 sub-categories belonging to 3 main Gene Ontology (GO) categories (ontologies). Using the transcriptome data as references, we analyzed the differential gene expressions between a soybean oil-fed group (SOF) and a lard oil-fed group (LOF), compared to the negative control group (NC), using the DGE approach. We finally obtained 1,566 differentially expressed genes in SOF/NC, and 1,099 genes in LOF/NC. For further analysis, GO and KEGG functional enrichment were performed on all differentially expressed genes, and a group of differentially expressed candidate genes related to lipometabolism were identified. Conclusions/Significance: This study provides a global survey of C. megacephala and provides the basis for further research on the functional genomics of this insect. [ABSTRACT FROM AUTHOR]

By adding different amount of zinc into the artificial medium of the insect larvae, the zinc-induced apoptosis of the larvae haemocytes of the herbivorous insect Spodoptera litura Fabricius was investigated with flow cytometer. The results showed that the increase of zinc dose in the artificial feed led to the accumulations of zinc in the larval hemolymph and fat body, and more zinc was accumulated in fat body than in hemolymph. The apoptosis of hemocytes was significantly induced at high zinc concentration (1000 mg·kg-1) in the insect diet, and the apoptosis rate was 63.63%, which was remarkably higher than that at control and lower concentrations (50–500 mg·kg-1). This suggests that the high dose of zinc in the artificial diet of S. litura larvae could induce the apoptosis of the larval hemocytes of S. litura. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide/SiO2 (RGO/SiO2) serving as a novel spherical support for Ziegler-Natta (Z-N) catalyst is reported. The surface and interior of the support has a porous architecture formed by RGO/SiO2 sandwich structure. The sandwich structure is like a brick wall coated with a graphene layer of concreted as skeleton which could withstand external pressures and endow the structure with higher support stabilities. After loading the Z-N catalyst, the active components anchor on the surface and internal pores of the supports. When the ethylene molecules meet the active centers, the molecular chains grow from the surface and internal catalytic sites in a regular and well-organized way. And the process of the nascent molecular chains filled in the sandwich structure polymerization could ensure the graphene disperse uniformly in the polymer matrix. Compared with traditional methods, the porous spherical graphene support of this strategy has far more advantages and could maintain an intrinsic graphene performance in the nanocomposites. [ABSTRACT FROM AUTHOR]

Bacterial translocation (BT) is thought to play an important role in the development of liver cirrhosis, but the mechanisms have not been fully explored. This study aims to investigate the distribution of Treg (CD3+CD4+CD25+Foxp3+), Th17 (CD3+CD4+IL-17+), and Th1 (CD3+CD4+IFN-γ+) cells in the intestinal lamina propria, liver and blood and to explore their relationships with BT. Cirrhotic rats with ascites were induced by CCl4. We found that there were lower levels of total protein and albumin, lower albumin/globulin ratio, lower body weight and higher spleen weight and ascites volume in cirrhotic rats with than without BT. We found that BT may cause increase of Treg cells in the proximal small intestine and decrease of Th17 cells in the whole intestine and blood in cirrhotic rats. It may also aggravate the CCl4-induced decrease in Th1 cells in the whole intestine, liver, caecum, and blood and the CCl4-induced increase in Th17 cells in the liver and Tregs in the distal small intestine, colon, and liver. Our data suggest that BT may aggravate liver injury and decrease liver function via an interaction with CD4+ T Cells. The results of this study may be helpful for the development of new treatments for liver cirrhosis. [ABSTRACT FROM AUTHOR]

The dissemination of Klebsiella pneumoniae carbapenemases (KPCs) among Gram-negative bacteria is an important threat to global health. However, KPC-producing bacteria from environmental samples are rarely reported. This study aimed to elucidate the underlying resistance mechanisms of three carbapenem-resistant Aeromonas taiwanensis isolates recovered from river sediment samples. Pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS) analysis indicated a close evolutionary relationship among A. taiwanensis isolates. S1-PFGE, Southern blot and conjugation assays confirmed the presence of bla KPC- 2 and qnrS2 genes on a non-conjugative plasmid in these isolates. Plasmid analysis further showed that pKPC-1713 is an IncP-6 plasmid with a length of 53,205 bp, which can be transformed into DH5α strain and mediated carbapenems and quinolones resistance. The plasmid backbone of p1713-KPC demonstrated 99% sequence identity to that of IncP-6-type plasmid pKPC-cd17 from Aeromonas spp. and IncP-6-type plasmid: 1 from Citrobacter freundii at 74% coverage. A 14,808 bp insertion sequence was observed between merT gene and hypothetical protein in p1713-KPC, which include the quinolone resistance qnrS2 gene. Emergence of plasmid-borned bla KPC and qnrS2 genes from A. taiwanensis isolates highlights their possible dissemination into the environment. Therefore, potential detection of such plasmids from clinical isolates should be closely monitored., (Copyright © 2019 Hu, Yu, Shang, Xu, Guo, Liang, Kang, Song, Sun, Yue, Mao and Zheng.)

Objectives: The bla KPC gene is rarely reported in Citrobacter koseri. Here we report the first draft genome sequence of a bla KPC-2 -carrying C. koseri isolate from a patient with diarrhoea., Methods: Transferability of the bla KPC-2 -bearing plasmid was determined by the filter mating method. The whole genome sequence of C. koseri L168 was determined using an Illumina HiSeq platform. The genome was de novo assembled using Velvet 1.2.10. Acquired antimicrobial resistance genes and plasmid replicons were identified using ResFinder 2.1 and PlasmidFinder 1.3, respectively., Results: Antimicrobial susceptibility testing (AST) showed that C. koseri L168 was resistant to multiple antibiotics but was susceptible to ciprofloxacin, gentamicin, tobramycin, amikacin, tigecycline and colistin. A KPC-2-harbouring plasmid was conjugative and the transconjugants conferred increased resistance to carbapenems confirmed by conjugation experiments and AST. In silico analysis revealed the presence of the β-lactam resistance genes bla KPC-2 and bla MAL-1 . Additionally, plasmids of incompatibility groups IncFII and IncX4 were identified in the genome by PlasmidFinder. BLAST analysis revealed that bla KPC-2 was located on a Tn3 transposon element in C. koseri L168 with the conserved linear structure ISKpn27-bla KPC-2 -ΔISKpn6-korC-klcA., Conclusions: To our knowledge, this is only the second report of C. koseri producing KPC-2, and we report the first draft genome sequence of a bla KPC-2 -carrying C. koseri isolate from a patient with diarrhoea in China. This work may facilitate our understanding of the pathogenesis, multidrug resistance mechanisms and genomic features of this species. Further monitoring of bacteria carrying carbapenemase genes in patients' gut microbiota is warranted., (Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.)

Alterations in the gut microbiome have been reported in liver cirrhosis, and probiotic interventions are considered a potential treatment strategy. This study aimed to evaluate the effects and mechanisms of Lactobacillus salivarius LI01, Pediococcus pentosaceus LI05, Lactobacillus rhamnosus GG, Clostridium butyricum MIYAIRI and Bacillus licheniformis Zhengchangsheng on CCl 4 -induced cirrhotic rats. Only administration of LI01 or LI05 prevented liver fibrosis and down-regulated the hepatic expression of profibrogenic genes. Serum endotoxins, bacterial translocations (BTs), and destruction of intestinal mucosal ultrastructure were reduced in rats treated with LI01 or LI05, indicating maintenance of the gut barrier as a mechanism; this was further confirmed by the reduction of not only hepatic inflammatory cytokines, such as TNF-α, IL-6, and IL-17A, but also hepatic TLR2, TLR4, TLR5 and TLR9. Metagenomic sequencing of 16S rRNA gene showed an increase in potential beneficial bacteria, such as Elusimicrobium and Prevotella, and a decrease in pathogenic bacteria, such as Escherichia. These alterations in gut microbiome were correlated with profibrogenic genes, gut barrier markers and inflammatory cytokines. In conclusion, L. salivarius LI01 and P. pentosaceus LI05 attenuated liver fibrosis by protecting the intestinal barrier and promoting microbiome health. These results suggest novel strategies for the prevention of liver cirrhosis.

Bacterial translocation (BT) is thought to play an important role in the development of liver cirrhosis, but the mechanisms have not been fully explored. This study aims to investigate the distribution of Treg (CD3 + CD4 + CD25 + Foxp3 + ), Th17 (CD3 + CD4 + IL-17 + ), and Th1 (CD3 + CD4 + IFN-γ + ) cells in the intestinal lamina propria, liver and blood and to explore their relationships with BT. Cirrhotic rats with ascites were induced by CCl 4 . We found that there were lower levels of total protein and albumin, lower albumin/globulin ratio, lower body weight and higher spleen weight and ascites volume in cirrhotic rats with than without BT. We found that BT may cause increase of Treg cells in the proximal small intestine and decrease of Th17 cells in the whole intestine and blood in cirrhotic rats. It may also aggravate the CCl 4 -induced decrease in Th1 cells in the whole intestine, liver, caecum, and blood and the CCl 4 -induced increase in Th17 cells in the liver and Tregs in the distal small intestine, colon, and liver. Our data suggest that BT may aggravate liver injury and decrease liver function via an interaction with CD4 + T Cells. The results of this study may be helpful for the development of new treatments for liver cirrhosis., Competing Interests: The authors declare no competing financial interests.

We report a draft genome sequence of Lactobacillus panis DSM 6035(T), isolated from sourdough. The genome of this strain is 2,082,789 bp long, with 47.9% G+C content. A total of 2,047 protein-coding genes were predicted., (Copyright © 2015 Zhu et al.)

Staphylococcus gallinarum DSM 20610(T) is a rare pathogen in humans. The increasing relevance of human health prompted us to determine the genomic sequence of S. gallinarum. The complete genome sequence of S. gallinarum includes a genome of 3,171,720 bp (33.02% G+C content) without any plasmids., (Copyright © 2015 Shi et al.)