295 research outputs found
New methods in provenance studies based on heavy minerals: an example from Miocene sands in Jylland, Denmark
New techniques using Computer Controlled Scanning Electron Microscopy (CCSEM) and Laser Ablation – Inductively Coupled Plasma – Mass Spectroscopy (LA-ICP-MS) have recently been developed at the Geological Survey of Denmark and Greenland (GEUS) to determine source, compositional variation and sedimentary pathways of sandstones. These new time- and cost-efficient methods are highly applicable in petroleum and mineral exploration. This paper illustrates how the provenance and variability of Miocene titanium-rich sands in western and central Jylland have been investigated, but the methods are presently also used offshore the Faroe Islands and in East and West Greenland. CCSEM and LA-ICP-MS utilise simple sample preparation methods, are relatively rapid and less expensive than conventional methods and yield more information
Bacterial Bio-indicators of Marcellus Shale Activities in Pennsylvania: A Molecular Ecology Survey
The practice of hydraulic fracking has increased over the years especially in Pennsylvania where most of the subterraneous gas-rich Marcellus Shale formations are located. Our previous work showed that headwater streams in proximity to hydraulic fracking operations have significantly different bacterial assemblages as compared to un-impacted streams in central PA. Aquatic bacterial communities are of great importance because they are often the ‘first-responders’ to environmental perturbations. We are interested in which bacteria become enriched, as this might serve as robust biomarkers of fracking, and can potentially biodegrade constituents of fracking fluids. In this study, we plan to expand upon our previous work to identify additional sentinel bacterial taxa in other areas in PA (Northeast and Southwest) heavily impacted by fracking. Water and sediment samples have been collected from Northern Pennsylvania (n=31) and Southwestern (n=11) regions upstream and downstream of fracking activities. Bacterial community profiles of these samples were generated via high-throughput sequencing of the 16S rRNA, a robust phylogenetic marker for bacterial identification. The data generated provide a snapshot of all bacteria taxa present and their relative abundance. Thus, differences in bacterial community structure between impacted and un-impacted environments can help glean which bacterial taxa are responding to environmental perturbations associated with fracking. This research can help us generate a list of potential bioindicators of nascent fracking activities and can be used to help track impacts and bioremediation potential within environmental scenarios
Early-life formula feeding is associated with infant gut microbiota alterations and an increased antibiotic resistance load
Background Infants are at a high risk of acquiring fatal infections, and their treatment relies on functioning antibiotics. Antibiotic resistance genes (ARGs) are present in high numbers in antibiotic-naive infants' gut microbiomes, and infant mortality caused by resistant infections is high. The role of antibiotics in shaping the infant resistome has been studied, but there is limited knowledge on other factors that affect the antibiotic resistance burden of the infant gut. Objectives Our objectives were to determine the impact of early exposure to formula on the ARG load in neonates and infants born either preterm or full term. Our hypotheses were that diet causes a selective pressure that influences the microbial community of the infant gut, and formula exposure would increase the abundance of taxa that carry ARGs. Methods Cross-sectionally sampled gut metagenomes of 46 neonates were used to build a generalized linear model to determine the impact of diet on ARG loads in neonates. The model was cross-validated using neonate metagenomes gathered from public databases using our custom statistical pipeline for cross-validation. Results Formula-fed neonates had higher relative abundances of opportunistic pathogens such as Staphylococcus aureus, Staphylococcus epidermidis, Klebsiella pneumoniae, Klebsiella oxytoca, and Clostridioides difficile. The relative abundance of ARGs carried by gut bacteria was 69% higher in the formula-receiving group (fold change, 1.69; 95% CI: 1.12-2.55; P = 0.013; n = 180) compared to exclusively human milk-fed infants. The formula-fed infants also had significantly less typical infant bacteria, such as Bifidobacteria, that have potential health benefits. Conclusions The novel finding that formula exposure is correlated with a higher neonatal ARG burden lays the foundation that clinicians should consider feeding mode in addition to antibiotic use during the first months of life to minimize the proliferation of antibiotic-resistant gut bacteria in infants.Peer reviewe
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Essiac? and Flor-Essence? herbal tonics stimulate the in vitro growth of human breast cancer cells
People diagnosed with cancer often self-administer complementary and alternative medicines (CAMs) to supplement their conventional treatments, improve health, or prevent recurrence. Flor-Essence{reg_sign} and Essiac{reg_sign} Herbal Tonics are commercially available complex mixtures of herbal extracts sold as dietary supplements and used by cancer patients based on anecdotal evidence that they can treat or prevent disease. In this study, we evaluated Flor-Essence{reg_sign} and Essiac{reg_sign} for their effects on the growth of human tumor cells in culture. The effect of Flor-Essence{reg_sign} and Essiac{reg_sign} herbal tonics on cell proliferation was tested in MCF-7, MDA-MB-436, MDA-MB-231, and T47D cancer cells isolated from human breast tumors. Estrogen receptor (ER) dependent activation of a luciferase reporter construct was tested in MCF-7 cells. Specific binding to the ER was tested using an ICI 182,780 competition assay. Flor-Essence{reg_sign} and Essiac{reg_sign} herbal tonics at 1%, 2%, 4% and 8% stimulated cell proliferation relative to untreated controls and activated ER dependent luciferase activity in MCF-7 cells. A 10{sup -7} M concentration of ICI 870,780 inhibited the induction of ER dependent luciferase activity by Flor-Essence{reg_sign} and Essiac{reg_sign}, but did not affect cell proliferation. Flor-Essence{reg_sign} and Essiac{reg_sign} Herbal Tonics can stimulate the growth of human breast cancer cells through ER mediated as well as ER independent mechanisms of action. Cancer patients and health care providers can use this information to make informed decisions about the use of these CAMs
Bacterial Community Dynamics In Dichloromethane-Contaminated Groundwater Undergoing Natural Attenuation
The uncontrolled release of the industrial solvent methylene chloride, also known as dichloromethane (DCM), has resulted in widespread groundwater contamination in the United States. Here we investigate the role of groundwater bacterial communities in the natural attenuation of DCM at an undisclosed manufacturing site in New Jersey. This study investigates the bacterial community structure of groundwater samples differentially contaminated with DCM to better understand the biodegradation potential of these autochthonous bacterial communities. Bacterial community analysis was completed using high-throughput sequencing of the 16S rRNA gene of groundwater samples (n = 26) with DCM contamination ranging from 0.89 to 9,800,000 μg/L. Significant DCM concentration-driven shifts in overall bacterial community structure were identified between samples, including an increase in the abundance of Firmicutes within the most contaminated samples. Across all samples, a total of 6,134 unique operational taxonomic units (OTUs) were identified, with 16 taxa having strong correlations with increased DCM concentration. Putative DCM degraders such as Pseudomonas, Dehalobacterium and Desulfovibrio were present within groundwater across all levels of DCM contamination. Interestingly, each of these taxa dominated specific DCM contamination ranges respectively. Potential DCM degrading lineages yet to be cited specifically as a DCM degrading organisms, such as the Desulfosporosinus, thrived within the most heavily contaminated groundwater samples. Co-occurrence network analysis revealed aerobic and anaerobic bacterial taxa with DCM-degrading potential were present at the study site. Our 16S rRNA gene survey serves as the first in situ bacterial community assessment of contaminated groundwater harboring DCM concentrations ranging over seven orders of magnitude. Diversity analyses revealed known as well as potentially novel DCM degrading taxa within defined DCM concentration ranges, indicating niche-specific responses of these autochthonous populations. Altogether, our findings suggest that monitored natural attenuation is an appropriate remediation strategy for DCM contamination, and that high-throughput sequencing technologies are a robust method for assessing the potential role of biodegrading bacterial assemblages in the apparent reduction of DCM concentrations in environmental scenarios.Frontiers in Microbiology 8. (2017
CHO-K1 host cells adapted to growth in glutamine-free medium by FACS-assisted evolution
Biomarkers of insulin resistance, oxidative stress, and nutrition and the brain
Alzheimer’s disease (AD) is a neurological disorder that has been linked with nutrition and lifestyle choices throughout the lifespan. Although there is currently no cure, recent research supports dietary changes as a preventative measure for AD. However, it is not clear which nutritional markers underlie the structural and functional changes in the brain that are seen in AD, and subsequently what aspect of the diet should be targeted in AD prevention and treatment. The projects described in this dissertation provide four nutritional biomarkers that are associated with AD pathology: the metabolism-regulating enzyme autotaxin, the insulin transporter and modifier insulin-like growth factor binding protein 2, the antioxidant superoxide dismutase 1, and the micronutrient involved in methylation of proteins and lipids as well as homocysteine metabolism, vitamin B12. These studies analyze neurological associations through region of interest approaches, voxel-wise analyses, and statistical analyses (i.e. linear mixed models, mediation models, logistic regression) with established cerebrospinal fluid (CSF) biomarkers of AD, cognitive test scores, and baseline and follow-up diagnoses. Our findings suggest that CSF autotaxin is detrimental to brain health and superoxide dismutase 1 is most likely beneficial. Insulin-like growth factor binding protein is suggested to be beneficial early in the AD trajectory, but detrimental as the disease progresses. Lastly, our results suggest that higher serum vitamin B12 may be indicative of worse AD outcomes in an aged population but contrastingly better cognitive associations in a young population. Future studies are needed to determine causation as well as the impact of nutritional modifications on these biomarkers and subsequent brain health.</p
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