Project description:We applied small RNA Solexa sequencing technology to identify microRNA expression in human liver samples from surgically removed liver tissues including three normal liver tissues (distal normal liver tissue of liver hemangioma), an hepatitis B virus (HBV)-infected liver, a severe chronic hepatitis B liver, two HBV-related hepatocellular carcinoma (HCC), an hepatitis C virus (HCV)-related HCC, and an HCC without HBV or HCV infection. All samples were collected with the informed consent of the patients and the experiments were approved by the ethics committee of Second Military Medical University, Shanghai, China. We investigated the miRNome in human normal liver and suggested some deregulated abundantly expressed microRNAs in HCC. center_name: National Key Laboratory of Medical Immunology & Institute of Immunology, Second Military Medical University, Shanghai, China.
Project description:Clonal emergence is a major driver for changes in bacterial disease epidemiology. Recently, it has been proposed that episodic emergence of novel, hypervirulent clones of group A Streptococcus (GAS) results from horizontal gene transfer (HGT) and recombination events leading to increased expression of the cytotoxins Nga (NADase) and SLO (streptolysin O). We previously described a gene fusion event involving the gene encoding the GAS M protein (emm) and an adjacent M-like protein (enn) in the emm4 GAS population, a GAS emm type that lacks the hyaluronic acid capsule. Using whole genome sequencing of a temporally and geographically diverse set of 1,127 isolates, we discovered that the North American emm4 GAS population has undergone clonal replacement with emergent GAS strains completely replacing historical isolates by 2017. Emergent emm4 GAS strains were defined by a handful of small genetic variations, including the emm-enn gene fusion, and showed a marked in vitro growth defect compared to historical strains. In contrast to other previously described GAS clonal emergence events, emergent emm4 GAS lacked significant HGT events and showed no significant increase in transcript levels of nga/slo toxin gene via RNA sequencing and quantitative real-time PCR analysis relative to historic strains. Despite the in vitro growth differences, emergent emm4 GAS strains demonstrated hypervirulence in mouse and ex vivo growth in human blood compared to historical strains. Thus, these data detail the emergence and dissemination of a hypervirulent acapsular GAS clone defined by small genetic variation thereby defining a novel model for GAS strain replacement.
Project description:Formalin induces inter- and intra-molecular crosslinks within exposed cells. This cross-linking can be exploited to characterise chromatin state as in the FAIRE (Formaldehyde-Assisted Isolation of Regulatory Elements) and MNase (micrococcal nuclease) assays. Here, we optimised the FAIRE and MNase assays for application upon heavily-fixed tissues as is typically found in historical formalin-preserved museum specimens. We demonstrate these assays in formalin-fixed mouse specimens and compare the chromatin signatures to specimen-matched fresh tissues. We found that heavy formalin fixation modulates rather than eliminates signatures of differential chromatin accessibility and that these chromatin profiles are reproducible, tissue-specific and sex-specific in vertebrate specimens.
Project description:Natural history museum specimens of historical honeybees have been successfully used to explore the genomic past of the honeybee, indicating fast and rapid changes between historical and modern specimens, possibly as a response to current challenges. In our study we explore a potential untapped archive from natural history collections - specimens of beeswax. We examine an Apis mellifera mellifera queen cell specimen from the 19th century. The intact and closed cell was analysed by X-ray Computed Tomography (CT) to reveal a perfectly preserved queen bee inside her cell. Subsequently, a micro-destructive approach was used to evaluate the possibility of protein extraction from the cell. Our results show that studies on specimens such as these provide valuable information about the past rearing of queens, their diet and development, which is relevant for understanding current honeybee behaviour. In addition we evaluate the feasibility of using historical beeswax as a biomolecular archive for ancient proteins to study honeybees.
Project description:A common technique used for sensitive and specific diagnostic virus detection in clinical samples is PCR. However, an unbiased diagnostic microarray containing probes for all human pathogens could replace hundreds of individual PCR-reactions and remove the need for a clear clinical hypothesis regarding a suspected pathogen. We have established such a diagnostic platform for unbiased random amplification and subsequent microarray identification of viral pathogens in clinical samples. We show that Phi29 polymerase-amplification of a diverse set of clinical samples generates enough viral material for successful identification by the Microbial Detection Array developed at the Lawrence Livermore National Laboratory, California, USA, demonstrating the potential of the microarray technique for broad-spectrum pathogen detection. We conclude that this method detects both DNA and RNA virus, present in the same sample, as well as differentiates between different virus subtypes. We propose this assay for unbiased diagnostic analysis of all viruses in clinical samples.
Project description:Formalin induces inter- and intra-molecular crosslinks within exposed cells. This cross-linking can be exploited to characterise chromatin state as in the FAIRE (Formaldehyde-Assisted Isolation of Regulatory Elements) and MNase (micrococcal nuclease) assays. Here, we optimised the FAIRE and MNase assays for application upon heavily-fixed tissues as is typically found in historical formalin-preserved museum specimens. We demonstrate these assays in formalin-fixed mouse specimens and compare the chromatin signatures to specimen-matched fresh tissues. We found that heavy formalin fixation modulates rather than eliminates signatures of differential chromatin accessibility and that these chromatin profiles are reproducible, tissue-specific and sex-specific in vertebrate specimens.
Project description:This study investigated the consumption of milk products in the archaeological record, utilizing human dental calculus as a reservoir of dietary proteins from archaeological samples from across Eurasia. Protein extraction and generation of tryptic peptides from dental calculus was performed using a filter-aided sample preparation (FASP) protocol, modified for ancient samples, on 92 samples of archaeological dental calculus. Samples were extracted at three laboratories; the Functional Genomics Centre Zürich (FGCZ), the Centre for GeoGenetics at the National History Museum of Denmark, and BioArCh at the University of York. Sample extracts were sequenced (LC-MS/MS) using an LTQ-Orbitrap Velos (FGCZ), a Q-Exactive Hybrid Quadrupole Orbitrap and an LTQ-Orbitrap Elite (Central Proteomics Facility, Target Discovery Institute, Oxford).
Project description:This study investigated the consumption of milk products in the archaeological record, utilizing human dental calculus as a reservoir of dietary proteins from archaeological samples from across Eurasia. Protein extraction and generation of tryptic peptides from dental calculus was performed using a filter-aided sample preparation (FASP) protocol, modified for ancient samples, on 92 samples of archaeological dental calculus. Samples were extracted at three laboratories; the Functional Genomics Centre Zürich (FGCZ), the Centre for GeoGenetics at the National History Museum of Denmark, and BioArCh at the University of York. Sample extracts were sequenced (LC-MS/MS) using an LTQ-Orbitrap Velos (FGCZ), a Q-Exactive Hybrid Quadrupole Orbitrap and an LTQ-Orbitrap Elite (Central Proteomics Facility, Target Discovery Institute, Oxford).