358 research outputs found

    High-sensitivity spin-based electrometry with an ensemble of nitrogen-vacancy centers in diamond

    Get PDF
    We demonstrate a spin-based, all-dielectric electrometer based on an ensemble of nitrogen-vacancy (NV[superscript −]) defects in diamond. An applied electric field causes energy-level shifts symmetrically away from the NV[superscript −]'s degenerate triplet states via the Stark effect; this symmetry provides immunity to temperature fluctuations allowing for shot-noise-limited detection. Using an ensemble of NV[superscript −]s, we demonstrate shot-noise-limited sensitivities approaching 1 (V/cm)/√Hz under ambient conditions, at low frequencies (<10 Hz), and over a large dynamic range (20 dB). A theoretical model for the ensemble of NV[superscript −]s fits well with measurements of the ground-state electric susceptibility parameter 〈k[subscript ⊥]〉. Implications of spin-based, dielectric sensors for micron-scale electric-field sensing are discussed.United States. National Aeronautics and Space Administration. Office of Chief Technologist (Space Technology Research Fellowship)United States. Air Force Office of Scientific Research. Presidential Early Career Award in Science and Engineerin

    CAPRG: Sequence Assembling Pipeline for Next Generation Sequencing of Non-Model Organisms

    Get PDF
    Our goal is to introduce and describe the utility of a new pipeline “Contigs Assembly Pipeline using Reference Genome” (CAPRG), which has been developed to assemble “long sequence reads” for non-model organisms by leveraging a reference genome of a closely related phylogenetic relative. To facilitate this effort, we utilized two avian transcriptomic datasets generated using ROCHE/454 technology as test cases for CAPRG assembly. We compared the results of CAPRG assembly using a reference genome with the results of existing methods that utilize de novo strategies such as VELVET, PAVE, and MIRA by employing parameter space comparisons (intra-assembling comparison). CAPRG performed as well or better than the existing assembly methods based on various benchmarks for “gene-hunting.” Further, CAPRG completed the assemblies in a fraction of the time required by the existing assembly algorithms. Additional advantages of CAPRG included reduced contig inflation resulting in lower computational resources for annotation, and functional identification for contigs that may be categorized as “unknowns” by de novo methods. In addition to providing evaluation of CAPRG performance, we observed that the different assembly (inter-assembly) results could be integrated to enhance the putative gene coverage for any transcriptomics study

    Multiple Environmental Stressors Induce Complex Transcriptomic Responses Indicative of Phenotypic Outcomes in Western Fence Lizard

    Get PDF
    Background The health and resilience of species in natural environments is increasingly challenged by complex anthropogenic stressor combinations including climate change, habitat encroachment, and chemical contamination. To better understand impacts of these stressors we examined the individual- and combined-stressor impacts of malaria infection, food limitation, and 2,4,6-trinitrotoluene (TNT) exposures on gene expression in livers of Western fence lizards (WFL, Sceloporus occidentalis) using custom WFL transcriptome-based microarrays. Results Computational analysis including annotation enrichment and correlation analysis identified putative functional mechanisms linking transcript expression and toxicological phenotypes. TNT exposure increased transcript expression for genes involved in erythropoiesis, potentially in response to TNT-induced anemia and/or methemoglobinemia and caused dose-specific effects on genes involved in lipid and overall energy metabolism consistent with a hormesis response of growth stimulation at low doses and adverse decreases in lizard growth at high doses. Functional enrichment results were indicative of inhibited potential for lipid mobilization and catabolism in TNT exposures which corresponded with increased inguinal fat weights and was suggestive of a decreased overall energy budget. Malaria infection elicited enriched expression of multiple immune-related functions likely corresponding to increased white blood cell (WBC) counts. Food limitation alone enriched functions related to cellular energy production and decreased expression of immune responses consistent with a decrease in WBC levels. Conclusions Despite these findings, the lizards demonstrated immune resilience to malaria infection under food limitation with transcriptional results indicating a fully competent immune response to malaria, even under bio-energetic constraints. Interestingly, both TNT and malaria individually increased transcriptional expression of immune-related genes and increased overall WBC concentrations in blood; responses that were retained in the TNT x malaria combined exposure. The results demonstrate complex and sometimes unexpected responses to multiple stressors where the lizards displayed remarkable resiliency to the stressor combinations investigated

    TOM40 Mediates Mitochondrial Dysfunction Induced by α-Synuclein Accumulation in Parkinson's Disease.

    Get PDF
    Alpha-synuclein (α-Syn) accumulation/aggregation and mitochondrial dysfunction play prominent roles in the pathology of Parkinson's disease. We have previously shown that postmortem human dopaminergic neurons from PD brains accumulate high levels of mitochondrial DNA (mtDNA) deletions. We now addressed the question, whether alterations in a component of the mitochondrial import machinery -TOM40- might contribute to the mitochondrial dysfunction and damage in PD. For this purpose, we studied levels of TOM40, mtDNA deletions, oxidative damage, energy production, and complexes of the respiratory chain in brain homogenates as well as in single neurons, using laser-capture-microdissection in transgenic mice overexpressing human wildtype α-Syn. Additionally, we used lentivirus-mediated stereotactic delivery of a component of this import machinery into mouse brain as a novel therapeutic strategy. We report here that TOM40 is significantly reduced in the brain of PD patients and in α-Syn transgenic mice. TOM40 deficits were associated with increased mtDNA deletions and oxidative DNA damage, and with decreased energy production and altered levels of complex I proteins in α-Syn transgenic mice. Lentiviral-mediated overexpression of Tom40 in α-Syn-transgenic mice brains ameliorated energy deficits as well as oxidative burden. Our results suggest that alterations in the mitochondrial protein transport machinery might contribute to mitochondrial impairment in α-Synucleinopathies

    Simplified RNA secondary structure mapping by automation of SHAPE data analysis

    Get PDF
    SHAPE (Selective 2′-hydroxyl acylation analysed by primer extension) technology has emerged as one of the leading methods of determining RNA secondary structure at the nucleotide level. A significant bottleneck in using SHAPE is the complex and time-consuming data processing that is required. We present here a modified data collection method and a series of algorithms, embodied in a program entitled Fast Analysis of SHAPE traces (FAST), which significantly reduces processing time. We have used this method to resolve the secondary structure of the first ∼900 nt of the hepatitis C virus (HCV) genome, including the entire core gene. We have also demonstrated the ability of SHAPE/FAST to detect the binding of a small molecule inhibitor to the HCV internal ribosomal entry site (IRES). In conclusion, FAST allows for high-throughput data processing to match the current high-throughput generation of data possible with SHAPE, reducing the barrier to determining the structure of RNAs of interest

    HVAD to HeartMate 3 left ventricular assist device exchange: Best practices recommendations

    Get PDF
    The HeartWare HVAD System (Medtronic) is a durable implantable left ventricular assist device that has been implanted in approximately 20,000 patients worldwide for bridge to transplant and destination therapy indications. In December 2020, Medtronic issued an Urgent Medical Device Communication informing clinicians of a critical device malfunction in which the HVAD may experience a delay or failure to restart after elective or accidental discontinuation of pump operation. Moreover, evolving retrospective comparative effectiveness studies of patients supported with the HVAD demonstrated a significantly higher risk of stroke and all-cause mortality when compared with a newer generation of a commercially available durable left ventricular assist device. Considering the totality of this new information on HVAD performance and the availability of an alternate commercially available device, Medtronic halted the sale and distribution of the HVAD System in June 2021. The decision to remove the HVAD from commercial distribution now requires the use of the HeartMate 3 left ventricular assist system (Abbott, Inc) if a patient previously implanted with an HVAD requires a pump exchange. The goal of this document is to review important differences in the design of the HVAD and HeartMate 3 that are relevant to the medical management of patients supported with these devices, and to assess the technical aspects of an HVAD-to-HeartMate 3 exchange. This document provides the best available evidence that supports best practices

    Broadly neutralizing antibody responses in a large longitudinal sub-Saharan HIV primary infection cohort

    Get PDF
    Author Summary Understanding how HIV-1-broadly neutralizing antibodies (bnAbs) develop during natural infection is essential to the design of an efficient HIV vaccine. We studied kinetics and correlates of neutralization breadth in a large sub-Saharan African longitudinal cohort of 439 participants with primary HIV-1 infection. Broadly nAb responses developed in 15% of individuals, on average three years after infection. Broad neutralization was associated with high viral load, low CD4+ T cell counts, virus subtype C infection and HLA*A3(-) genotype. A correlation with high overall plasma IgG levels and anti-Env binding titers was also found. Specificity mapping of the bnAb responses showed that glycan-dependent epitopes, in particular the N332 region, were most commonly targeted, in contrast to other bnAb epitopes, suggesting that the HIV Env N332-glycan epitope region may be a favorable target for vaccine design

    Bridging the Gap: Collaboration between a School of Pharmacy, Public Health, and Governmental Organizations to provide Clinical and Economic Services to Medicare Beneficiaries

    Get PDF
    Objective: Promoting healthy communities through the provision of accessible quality healthcare services is a common mission shared by schools of pharmacy, public health departments, and governmental agencies. The following study seeks to identify and detail the benefits of collaboration between these different groups. Methods: In total, 112 mobile clinics targeting Medicare beneficiaries were held in 20 cities across Northern/Central California from 2007 to 2016. Under the supervision of licensed pharmacists, trained student pharmacists provided vaccinations, health screenings, Medicare Part D plan optimization services, and Medication Therapy Management (MTM) to patients at each clinic site. Clinic support was extended by public health departments, governmental agency partners, and a health professional program. Results: Since clinic inception, 8,996 patients were provided services. In total, 19,441 health screenings and 3,643 vaccinations were collectively provided to clinic patients. We assisted 5,549 beneficiaries with their Part D benefit, resulting in an estimated aggregate out-of-pocket drug cost savings of $5.7 million. Comprehensive MTM services were provided to 4,717 patients during which 8,184 medication-related problem (MRP) were identified. In 15.3% of patients, the MRP was determined severe enough to warrant prescriber follow-up. In total, 42.9% of clinic patients were from racial/ethnic minority groups and 25.5% had incomes ≤150% of the Federal Poverty Level. Conclusion: Collaboration between a school of pharmacy, public health departments, and governmental organizations can effectively serve Medicare beneficiary populations and result in: 1) lower out-of-pocket drug costs, 2) minimization of medication-related problems, 3) increased vaccination uptake, and 4) increased utilization of health screenings. Conflict of Interest We declare no conflicts of interest or financial interests that the authors or members of their immediate families have in any product or service discussed in the manuscript, including grants (pending or received), employment, gifts, stock holdings or options, honoraria, consultancies, expert testimony, patents and royalties. Treatment of Human Subjects: IRB review/approval required and obtained &nbsp; Type: Original Researc

    The Sudden Dominance of blaCTX–M Harbouring Plasmids in Shigella spp. Circulating in Southern Vietnam

    Get PDF
    Shigellosis is a disease caused by bacteria belonging to Shigella spp. and is a leading cause of bacterial gastrointestinal infections in infants in unindustrialized countries. The Shigellae are dynamic and capable of rapid change when placed under selective pressure in a human population. Extended spectrum beta lactamases (ESBLs) are enzymes capable of degrading cephalosporins (a group of antimicrobial agents) and the genes that encode them are common in pathogenic E. coli and other related organisms in industrialized countries. In southern Vietnam, we have isolated multiple cephalosporin-resistant Shigella that express ESBLs. Furthermore, over two years these strains have replaced strains isolated from patients with shigellosis that cannot express ESBLs. Our work describes the genes responsible for this characteristic and we investigate one of the elements carrying one of these genes. These finding have implications for treatment of shigellosis and support the growing necessity for vaccine development. Our findings also may be pertinent for other countries undergoing a similar economic transition to Vietnam's and the corresponding effect on bacterial populations
    corecore