Project description:Embryo DNA fingerprinting represents an important tool for tracking embryo-specific outcomes after multiple embryo transfer during IVF. The situation in which 2 embryos are transferred and only one implants represents a unique opportunity for the most well-controlled comparison of competent and incompetent embryos. Specifically, this design eliminates all patient-related variables from the comparison of embryos with or without reproductive potential. However, in order to determine which embryo implanted, the investigator must wait until newborn DNA is available upon delivery. This study validates a non-invasive fetal DNA fingerprinting method that reduces the time to identify which embryo implanted by approximately 31 weeks. Thirty-four patients were studied to determine if fingerprinting of fetal DNA extracted from maternal plasma at 9 gestational weeks concurred with the buccal DNA results obtained from the newborn after delivery. This validation required single nucleotide polymorphism (SNP) profiles on each couples’ preimplantation embryos, enriched fetal DNA from maternal plasma at 9 weeks gestation, and newborn DNA obtained from buccal swabs after delivery. The predictions from fetal DNA-based embryo tracking and gender assignments made at 9 weeks gestation were 100% consistent with standardized methods of assessment performed after term delivery. This study demonstrates the first validated fetal DNA fingerprinting method which predicts both gender and which embryo implanted at 9 weeks gestation following multiple embryo transfer. Affymetrix SNP arrays were processed and successfully completed according to the manufacturer's directions on DNA extracted from 136 embryos, 33 parental blood samples, 17 enriched fetal DNA samples and 21 buccal DNA samples.
Project description:Embryo DNA fingerprinting represents an important tool for tracking embryo-specific outcomes after multiple embryo transfer during IVF. The situation in which 2 embryos are transferred and only one implants represents a unique opportunity for the most well-controlled comparison of competent and incompetent embryos. Specifically, this design eliminates all patient-related variables from the comparison of embryos with or without reproductive potential. However, in order to determine which embryo implanted, the investigator must wait until newborn DNA is available upon delivery. This study validates a non-invasive fetal DNA fingerprinting method that reduces the time to identify which embryo implanted by approximately 31 weeks. Thirty-four patients were studied to determine if fingerprinting of fetal DNA extracted from maternal plasma at 9 gestational weeks concurred with the buccal DNA results obtained from the newborn after delivery. This validation required single nucleotide polymorphism (SNP) profiles on each couples’ preimplantation embryos, enriched fetal DNA from maternal plasma at 9 weeks gestation, and newborn DNA obtained from buccal swabs after delivery. The predictions from fetal DNA-based embryo tracking and gender assignments made at 9 weeks gestation were 100% consistent with standardized methods of assessment performed after term delivery. This study demonstrates the first validated fetal DNA fingerprinting method which predicts both gender and which embryo implanted at 9 weeks gestation following multiple embryo transfer.
Project description:The model prokaryote Escherichia coli can exist as a either a commensal or a pathogen in the gut of diverse mammalian hosts. These associations, coupled with its ease of cultivation and genetic variability, have made E. coli a popular indicator organism for tracking the origin of fecal water contamination. Source tracking accuracy is predicated on the assumption that E. coli isolates recovered from contaminated water present a genetic signature characteristic of the host from which they originated. In this study, we compared the accuracy with which E. coli isolated from humans, bear, cattle and deer could be identified by standard fingerprinting methods used for library-based microbial source tracking (repetitive element PCR and pulsed-field gel electrophoresis) in relation to microarray-based analysis of genome content. Our results show that patterns of gene presence or absence were more useful for distinguishing E. coli isolates from different sources than traditional fingerprinting methods, particularly in the case of human strains. Host-associated differences in genome composition included the presence or absence of mobile IS1 elements as well as genes encoding the ferric dicitrate iron transporter (fec), E. coli common pilus (ECP), type 1 fimbriae and the CRISPR associated cas proteins. Many of these differences occurred in regions of the E. coli chromosome previously shown to be “hot spots” for the integration of horizontally-acquired DNA. PCR primers designed to amplify the IS1 and fec loci confirmed array results and demonstrated the ease with which gene presence/absence data can be converted into a diagnostic assay. The data presented here suggest that, despite the high level of genetic diversity observed among isolates by PFGE, human-derived strains may constitute a distinct ecotype distinguished by multiple potential library-independent source tracking markers.
Project description:<p class='ql-align-justify'>The gut microbiome has been associated with pathological neurophysiological evolvement in extremely premature infants suffering from brain injury. The exact underlying mechanism and its associated metabolic signatures in infants are not fully understood. To decipher metabolite profiles linked to neonatal brain injury, we investigated the longitudinal fecal and plasma metabolome of 51 extremely premature infants using LC-HRMS-based untargeted metabolomics. This was expanded by an investigation of bile acids and amidated bile acid conjugates in feces and plasma by LC-MS/MS-based targeted metabolomics. The resulting data was integrated with 16S rRNA gene amplicon gut microbiome profiles as well as patient cytokine, growth factor and T-cell profiles. We identified an early onset of differentiation in neuroactive metabolites and bile acids between infants with and without brain injury. We detected several bacterially-derived bile acid amino acid conjugates and secondary bile acids in the plasma already 3 days after delivery, indicating the early establishment of a metabolically active gut microbiome. These results give new insights into the early life metabolome of extremely premature infants.</p>
Project description:The model prokaryote Escherichia coli can exist as a either a commensal or a pathogen in the gut of diverse mammalian hosts. These associations, coupled with its ease of cultivation and genetic variability, have made E. coli a popular indicator organism for tracking the origin of fecal water contamination. Source tracking accuracy is predicated on the assumption that E. coli isolates recovered from contaminated water present a genetic signature characteristic of the host from which they originated. In this study, we compared the accuracy with which E. coli isolated from humans, bear, cattle and deer could be identified by standard fingerprinting methods used for library-based microbial source tracking (repetitive element PCR and pulsed-field gel electrophoresis) in relation to microarray-based analysis of genome content. Our results show that patterns of gene presence or absence were more useful for distinguishing E. coli isolates from different sources than traditional fingerprinting methods, particularly in the case of human strains. Host-associated differences in genome composition included the presence or absence of mobile IS1 elements as well as genes encoding the ferric dicitrate iron transporter (fec), E. coli common pilus (ECP), type 1 fimbriae and the CRISPR associated cas proteins. Many of these differences occurred in regions of the E. coli chromosome previously shown to be M-bM-^@M-^\hot spotsM-bM-^@M-^] for the integration of horizontally-acquired DNA. PCR primers designed to amplify the IS1 and fec loci confirmed array results and demonstrated the ease with which gene presence/absence data can be converted into a diagnostic assay. The data presented here suggest that, despite the high level of genetic diversity observed among isolates by PFGE, human-derived strains may constitute a distinct ecotype distinguished by multiple potential library-independent source tracking markers. Twelve isolates of E. coli ( 3 from bear, 3 from cattle, 3 from deer and 3 from humans) were isolated from feces and/or raw sewage. Genome content for each strain was assessed in duplicate using comparative genome hybridization with E. coli K12 MG1655 as the reference for a total of 24 arrays.
Project description:The anaerobic digestion microbiomes has been puzzling us since the dawn of molecular methods for mixed microbial community analysis. Monitoring of the anaerobic digestion microbiome can either take place via a holistic evaluation of the microbial community through fingerprinting or by targeted monitoring of selected taxa. Here, we compared four different microbial community fingerprinting methods, i.e., amplicon sequencing, metaproteomics, metabolomics and phenotypics, in their ability to reflect the full-scale anaerobic digestion microbiome. The phenotypic fingerprinting reflects a, for anaerobic digestion, novel, single cell-based approach of direct microbial community fingerprinting. Three different digester types, i.e., sludge digesters, digesters treating agro-industrial waste and dry anaerobic digesters reflected different operational parameters. The α-diversity analysis yielded inconsistent results, especially for richness, across the different methods. In contrast, β-diversity analysis resulted in comparable profiles, even when translated into phyla or functions, with clear separation of the three digester types. In-depth analysis of each method's features i.e., operational taxonomic units, metaproteins, metabolites, and phenotypic traits, yielded certain similar features yet, also some clear differences between the different methods, which was related to the complexity of the anaerobic digestion process. In conclusion, phenotypic fingerprinting is a reliable, fast method for holistic monitoring of the anaerobic digestion microbiome, and the complementary identification of key features through other methods could give rise to a direct interpretation of anaerobic digestion process performance.