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1.
JMIR Cardio ; 8: e49590, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38265849

ABSTRACT

BACKGROUND: The gap in anticoagulation use among patients with atrial fibrillation (AF) is a major public health threat. Inadequate patient education contributes to this gap. Patient portal-based messaging linked to educational materials may help bridge this gap, but the most effective messaging approach is unknown. OBJECTIVE: This study aims to compare the responsiveness of patients with AF to an AF or anticoagulation educational message between 2 portal messaging approaches: sending messages targeted at patients with upcoming outpatient appointments 1 week before their scheduled appointment (targeted) versus sending messages to all eligible patients in 1 blast, regardless of appointment scheduling status (blast), at 2 different health systems: the University of Massachusetts Chan Medical School (UMass) and the University of Florida College of Medicine-Jacksonville (UFL). METHODS: Using the 2 approaches, we sent patient portal messages to patients with AF and grouped patients by high-risk patients on anticoagulation (group 1), high-risk patients off anticoagulation (group 2), and low-risk patients who may become eligible for anticoagulation in the future (group 3). Risk was classified based on the congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke, vascular disease, age between 65 and 74 years, and sex category (CHA2DS2-VASc) score. The messages contained a link to the Upbeat website of the Heart Rhythm Society, which displays print and video materials about AF and anticoagulation. We then tracked message opening, review of the website, anticoagulation use, and administered patient surveys across messaging approaches and sites using Epic Systems (Epic Systems Corporation) electronic health record data and Google website traffic analytics. We then conducted chi-square tests to compare potential differences in the proportion of patients opening messages and other evaluation metrics, adjusting for potential confounders. All statistical analyses were performed in SAS (version 9.4; SAS Institute). RESULTS: We sent 1686 targeted messages and 1450 blast messages. Message opening was significantly higher with the targeted approach for patients on anticoagulation (723/1156, 62.5% vs 382/668, 57.2%; P=.005) and trended the same in patients off anticoagulation; subsequent website reviews did not differ by messaging approach. More patients off anticoagulation at baseline started anticoagulation with the targeted approach than the blast approach (adjusted percentage 9.3% vs 2.1%; P<.001). CONCLUSIONS: Patients were more responsive in terms of message opening and subsequent anticoagulation initiation with the targeted approach.

2.
J Mol Recognit ; 36(1): e2993, 2023 01.
Article in English | MEDLINE | ID: mdl-36112092

ABSTRACT

Atomic force microscopy (AFM) was used to conduct single-molecule imaging of protein/DNA complexes involved in the regulation of the arabinose operon of Escherichia coli. In the presence of arabinose, the transcription regulatory protein AraC binds to a 38 bp region consisting of the araI1 and araI2 half-sites. The domain positioning of full-length AraC, when bound to DNA, was not previously known. In this study, AraC was combined with 302 and 560 bp DNA and arabinose, deposited on a mica substrate, and imaged with AFM in air. High resolution images of 560 bp DNA, where bound protein was visible, showed that AraC induces a bend in the DNA with an angle 60° ± 12° with a median of 55°. These results are consistent with earlier gel electrophoresis measurements that measured the DNA bend angle based on migration rates. By using known domain structures of AraC, geometric constraints, and contacts determined from biochemical experiments, we developed a model of the tertiary and quaternary structure of DNA-bound AraC in the presence of arabinose. The DNA bend angle predicted by the model is in agreement with the measurement values. We discuss the results in view of other regulatory proteins that cause DNA bending and formation of the open complex to initiate transcription.


Subject(s)
AraC Transcription Factor , Escherichia coli Proteins , AraC Transcription Factor/genetics , AraC Transcription Factor/chemistry , AraC Transcription Factor/metabolism , Escherichia coli Proteins/metabolism , Microscopy, Atomic Force , Cytarabine/metabolism , Repressor Proteins/metabolism , DNA, Bacterial/genetics , DNA, Bacterial/metabolism , Bacterial Proteins/metabolism , Arabinose/chemistry , Arabinose/metabolism , Arabinose/pharmacology , Transcription Factors/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , DNA/metabolism , Protein Binding
3.
Cardiovasc Digit Health J ; 3(5): 241-246, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36310680

ABSTRACT

Background: The main approach to preventing stroke in patients with atrial fibrillation (AF) is anticoagulation (AC), but only about 60% of at-risk individuals are on AC. Patient-facing electronic health record-based interventions have produced mixed results. Little is known about the impact of health portal-based messaging on AC use. Objective: The purpose of this study was describe a protocol we will use to measure the association between AC use and patient portal message opening. We also will measure patient attitudes toward education materials housed on a professional society Web site. Methods: We will send portal messages to patients aged ≥18 years with AF 1 week before an office/teleconference visit with a primary care or cardiology provider. The message will be customized for 3 groups of patients: those on AC; those at elevated risk but off AC; and those not currently at risk but may be at risk in the future. Within the message, we will embed a link to UpBeat.org, a Web site of the Heart Rhythm Society containing patient educational materials. We also will embed a link to a survey. Among other things, the survey will request patients to rate their attitude toward the Heart Rhythm Society Web pages. To measure the effectiveness of the intervention, we will track AC use and its association with message opening, adjusting for potential confounders. Conclusion: If we detect an increase in AC use correlates with message opening, we will be well positioned to conduct a future comparative effectiveness trial. If patients rate the UpBeat.org materials highly, patients from other institutions also may benefit from receiving these materials.

4.
Sci Rep ; 10(1): 11908, 2020 07 17.
Article in English | MEDLINE | ID: mdl-32681044

ABSTRACT

Carbon nanotube porins (CNTPs), short pieces of carbon nanotubes capable of self-inserting into a lipid bilayer, represent a simplified model of biological membrane channels. We have used high-speed atomic force microscopy (HS-AFM) and all-atom molecular dynamics (MD) simulations to study the behavior of CNTPs in a mixed lipid membrane consisting of DOPC lipid with a variable percentage of DMPC lipid added to it. HS-AFM data reveal that the CNTPs undergo diffusive motion in the bilayer plane. Motion trajectories extracted from the HS-AFM movies indicate that CNTPs exhibit diffusion coefficient values broadly similar to values reported for membrane proteins in supported lipid bilayers. The data also indicate that increasing the percentage of DMPC leads to a marked slowing of CNTP diffusion. MD simulations reveal a CNTP-lipid assembly that diffuses in the membrane and show trends that are consistent with the experimental observations.

5.
Front Microbiol ; 10: 1486, 2019.
Article in English | MEDLINE | ID: mdl-31312189

ABSTRACT

Soils are crucial in regulating ecosystem processes, such as nutrient cycling, and supporting plant growth. To a large extent, these functions are carried out by highly diverse and dynamic soil microbiomes that are in turn governed by numerous environmental factors including weathering profile and vegetation. In this study, we investigate geophysical and vegetation effects on the microbial communities of iron-rich lateritic soils in the highly weathered landscapes of Western Australia (WA). The study site was a lateritic hillslope in southwestern Australia, where gradual erosion of the duricrust has resulted in the exposure of the different weathering zones. High-throughput amplicon sequencing of the 16S rRNA gene was used to investigate soil bacterial community diversity, composition and functioning. We predicted that shifts in the microbial community would reflect variations in certain edaphic properties associated with the different layers of the lateritic profile and vegetation cover. Our results supported this hypothesis, with electrical conductivity, pH and clay content having the strongest correlation with beta diversity, and many of the differentially abundant taxa belonging to the phyla Actinobacteria and Proteobacteria. Soil water repellence, which is associated with Eucalyptus vegetation, also affected beta diversity. This enhanced understanding of the natural system could help to improve future crop management in WA since the physicochemical properties of the agricultural soils in this region are inherited from laterites via the weathering and pedogenesis processes.

6.
Proteins ; 82(12): 3385-96, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25243377

ABSTRACT

Many mutations in the N-terminal arm of AraC result in constitutive behavior in which transcription of the araBAD genes occurs even in the absence of arabinose. To begin to understand the mechanism underlying this class of mutations, we used molecular dynamics with self-guided Langevin dynamics to simulate (1) wild-type (WT) AraC, (2) known constitutive mutants resulting from alterations in the regulatory arm, particularly alanine and glycine substitutions at residue 8 because P8G is constitutive, whereas P8A behaves like wild type, and (3) selected variant AraC proteins containing alterations in the dimerization core. In all of the constitutive arm mutants, but not the WT protein, residues 37-42, which are located in the core of the dimerization domain, became restructured. This raised the question of whether or not these structural changes are an obligatory component of constitutivity. Using molecular dynamics, we identified alterations in the core that produced a similar restructuring. The corresponding mutants were constructed and their ara constitutivity status was determined experimentally. Because the core mutants were not found to be constitutive, we conclude that restructuring of core residues 37-42 does not, itself, lead to constitutivity of AraC. The available data lead to the hypothesis that the interaction of the N-terminal arm with something other than the front lip is the primary determinant of the inducing versus repressing state of AraC.


Subject(s)
AraC Transcription Factor/metabolism , Arabinose/metabolism , Escherichia coli Proteins/metabolism , Escherichia coli/metabolism , Gene Expression Regulation, Bacterial , Models, Molecular , Operon , Alanine , Allosteric Regulation , Amino Acid Substitution , AraC Transcription Factor/chemistry , AraC Transcription Factor/genetics , Biocatalysis , Catalytic Domain , Databases, Protein , Dimerization , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Glycine , Molecular Dynamics Simulation , Mutagenesis, Site-Directed , Mutation , Proline , Protein Conformation , Protein Interaction Domains and Motifs
7.
Opt Lett ; 39(18): 5362-5, 2014 Sep 15.
Article in English | MEDLINE | ID: mdl-26466272

ABSTRACT

Ultrafast optical beam rotation is proposed for single-shot, time-resolved measurements. A pump-probe configuration is considered using a diffraction grating and focusing optics to create angular encoding of the time delay between the pump and probe pulses. The characteristic time t(ap) of the grating-lens system is derived as a function of dispersion, NA, and time window T. An analytical equation for time resolution is obtained that incorporates t(ap)laser pulse width, and beam crossing, enabling optimum selection of optical components. For commercial standard gratings with width W≤50 mm, laser λ=800 nm, and NA=.05, a 160 ps time window can be achieved, and t(ap)=23 fs for T=1 ps.

8.
Chest ; 135(3 Suppl): 56S-61S, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19265077

ABSTRACT

BACKGROUND: The Agency for Healthcare Research and Quality (AHRQ) Evidence Report identified and assessed audience characteristics (internal factors) and external factors that influence the effectiveness of continuing medical education (CME) in changing physician behavior. METHODS: Thirteen studies examined a series of CME audience characteristics (internal factors), and six studies looked at external factors to reinforce the effects of CME in changing behavior. RESULTS: With regard to CME audience characteristics, the 13 studies examined age, gender, practice setting, years in practice, specialty, foreign vs US medical graduate, country of practice, personal motivation, nonmonetary rewards and motivations, learning satisfaction, and knowledge enhancement. With regard to the external characteristics, the six studies looked at the role of regulation, state licensing boards, professional boards, hospital credentialing, external audits, monetary and financial rewards, academic advancement, provision of tools, public demand and expectations, and CME credit. No consistent findings were identified. CONCLUSIONS: The AHRQ Evidence Report provides no conclusions about the ways that internal or external factors influence CME effectiveness in changing physician behavior. However, given what is known about how individuals approach learning, it is likely that internal factors play an important role in the design of effective CME. Regulatory and professional organizations are providing new structures, mandates, and recommendations for CME activities that influence the way CME providers design and present activities, supporting a role that is not yet clear for external factors. More research is needed to understand the impact of these factors in enhancing the effectiveness of CME.


Subject(s)
Evidence-Based Medicine/education , Physician's Role/psychology , Practice Guidelines as Topic/standards , Attitude of Health Personnel , Clinical Competence , Evidence-Based Medicine/standards , Humans , United States
9.
Chest ; 135(3 Suppl): 69S-75S, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19265079

ABSTRACT

To ensure that continuing medical education (CME) continues to evolve so that it offers educational activities that are relevant to physicians in keeping with the definition of CME, CME providers must respond to and prepare for emerging expectations. This article puts into context the impact of the current emphasis on lifelong learning in medicine, particularly the requirement for maintenance of certification and licensure, on CME. Further, the effect of changing needs assessments and the impact of the integration of new technology in CME is included. Finally, a discussion of the emerging unique needs of CME providers and organizations related to these changes are addressed in the following four broad categories: CME as a value center, resources in support of CME, research to further advance the field, and leadership to guide the profession.


Subject(s)
Education, Medical, Continuing/trends , Evidence-Based Medicine/trends , Clinical Competence , Education, Medical, Continuing/standards , Evidence-Based Medicine/standards , Forecasting , Humans , Licensure/standards , United States
10.
Environ Microbiol ; 8(3): 490-503, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16478455

ABSTRACT

We used slot blot hybridization, quantitative polymerase chain reaction (qPCR), and flow cytometry microarrays to quantify specific 16S rDNAs in weekly fecal specimens from four monkeys housed in a research vivarium for periods ranging from five to 8 months. Even in these uniformly housed and fed animals the gut microbiota is idiosyncratic, very dynamic on short timescales, and shows significant positive and negative correlations among some bacteria as well as responses to heavy metal exposure. The relative quantification (fmol targets per total fmol bacterial 16S rDNA) afforded by flow cytometry microarrays agreed well with the absolute quantification (nanogram of target DNA per nanogram of fecal DNA) afforded by slot blots and qPCR. We also noted strengths and weaknesses in inter-method comparisons for DNA-based quantification of these complex bacterial communities.


Subject(s)
Bacteria/growth & development , Feces/microbiology , Haplorhini/microbiology , Animals , Anti-Bacterial Agents/pharmacology , Biodiversity , Colony Count, Microbial , DNA, Bacterial/analysis , DNA, Ribosomal/analysis , Flow Cytometry , Male , Metals, Heavy/pharmacology , Nucleic Acid Hybridization , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics
11.
Cytometry A ; 60(2): 135-44, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15290714

ABSTRACT

BACKGROUND: Complex mixtures of DNA may be found in environmental and medical samples. There is a need for techniques that can measure low concentrations of target DNAs. For a multiplexed, flow cytometric assay, we show that the signal-to-noise ratio for fluorescence detection may be increased with the use of 3DNA dendrimers. A single fluorescent DNA molecule per bead could be detected with conventional flow cytometry instrumentation. METHODS: The analyte consisted of single-stranded (ss) DNA amplicons that were hybridized to capture probes on the surface of fluorescent polystyrene microspheres (beads) and initially labeled with streptavidin-R-phycoerythrin (single-step labeling). These beads have a low reporter fluorescence background and high efficiency of DNA hybridization. The DNA/SA-RPE complex was then labeled with 3DNA dendrimers and SA-RPE. The bead complexes were detected with a Luminex 100 flow cytometer. Bead standards were developed to convert the intensity to the number of SA-RPE labels per bead and the number of dendrimers per bead. RESULTS: The dendrimer assay resulted in 10-fold fluorescence amplification compared with single-step SA-RPE labeling. Based on concentration curves of pure target ss-amplicons, the signal-to-noise ratio of the dendrimer assay was greater by a factor of 8.5 over single-step SA-RPE labeling. The dendrimer assay was tested on 16S ribosomal DNA amplified from filter retentates of contaminated groundwater. Multiplexed detection of a single dendrimer-labeled DNA molecule per bead was demonstrated. CONCLUSIONS: Multiplexed detection of DNA hybridization on a single molecule level per bead was achieved with conventional flow cytometry instrumentation. This assay is useful for detecting target DNAs at low concentrations.


Subject(s)
DNA/analysis , Flow Cytometry/methods , Calibration , DNA/chemistry , Fluorescent Dyes/chemistry , Microspheres , Nucleic Acid Hybridization , Phycoerythrin/chemistry , Sensitivity and Specificity , Streptavidin/chemistry
12.
Appl Environ Microbiol ; 69(10): 5884-91, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14532040

ABSTRACT

The potential for removing uranium from contaminated groundwater by stimulating the in situ activity of dissimilatory metal-reducing microorganisms was evaluated in a uranium-contaminated aquifer located in Rifle, Colo. Acetate (1 to 3 mM) was injected into the subsurface over a 3-month period via an injection gallery composed of 20 injection wells, which was installed upgradient from a series of 15 monitoring wells. U(VI) concentrations decreased in as little as 9 days after acetate injection was initiated, and within 50 days uranium had declined below the prescribed treatment level of 0.18 micro M in some of the monitoring wells. Analysis of 16S ribosomal DNA (rDNA) sequences and phospholipid fatty acid profiles demonstrated that the initial loss of uranium from the groundwater was associated with an enrichment of Geobacter species in the treatment zone. Fe(II) in the groundwater also increased during this period, suggesting that U(VI) reduction was coincident with Fe(III) reduction. As the acetate injection continued over 50 days there was a loss of sulfate from the groundwater and an accumulation of sulfide and the composition of the microbial community changed. Organisms with 16S rDNA sequences most closely related to those of sulfate reducers became predominant, and Geobacter species became a minor component of the community. This apparent switch from Fe(III) reduction to sulfate reduction as the terminal electron accepting process for the oxidation of the injected acetate was associated with an increase in uranium concentration in the groundwater. These results demonstrate that in situ bioremediation of uranium-contaminated groundwater is feasible but suggest that the strategy should be optimized to better maintain long-term activity of Geobacter species.


Subject(s)
Acetates/metabolism , Fresh Water/microbiology , Geobacter/growth & development , Uranium/metabolism , Water Pollution, Chemical , Acetates/pharmacology , DNA, Ribosomal/analysis , Ecosystem , Fatty Acids/analysis , Ferric Compounds/metabolism , Fresh Water/chemistry , Geobacter/drug effects , Geobacter/metabolism , Mining , Oxidation-Reduction , Phospholipids/analysis , RNA, Ribosomal, 16S/genetics , Sulfates/metabolism
13.
Nucleic Acids Res ; 31(13): 3746-50, 2003 Jul 01.
Article in English | MEDLINE | ID: mdl-12824409

ABSTRACT

PROBEmer (http://probemer.cs.loyola.edu) is a web-based software tool that enables a researcher to select optimal oligos for PCR applications and multiplex detection platforms including oligonucleotide microarrays and bead-based arrays. Given two groups of nucleic-acid sequences, a target group and a non-target group, the software identifies oligo sequences that occur in members of the target group, but not in the non-target group. To help predict potential cross hybridization, PROBEmer computes all near neighbors in the non-target group and displays their alignments. The software has been used to obtain genus-specific prokaryotic probes based on the 16S rRNA gene, gene-specific probes for expression analyses and PCR primers. In this paper, we describe how to use PROBEmer, the computational methods it employs, and experimental results for oligos identified by this software tool.


Subject(s)
DNA Probes/chemistry , Molecular Probe Techniques , Oligonucleotide Probes/chemistry , Sequence Analysis, DNA/methods , Software , Algorithms , Bacteria/genetics , Computational Biology , DNA Primers/chemistry , Databases, Genetic , Gene Expression Profiling/methods , Genome, Fungal , Internet , Oligonucleotide Array Sequence Analysis/methods , Open Reading Frames , Polymerase Chain Reaction/methods , RNA, Ribosomal, 16S/genetics , Saccharomyces cerevisiae/genetics , User-Computer Interface
14.
Appl Environ Microbiol ; 68(2): 1010-3, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11823255

ABSTRACT

A first application of a multiplexed, bead-based method is described for determining the abundances of target sequences in an environmental PCR product. Target sequences as little as 0.3% of the total amount of DNA can be quantified. Tests were conducted on 16S ribosomal DNA sequences from microorganisms collected from contaminated groundwater.


Subject(s)
DNA, Bacterial/analysis , Flow Cytometry , Fresh Water/microbiology , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , DNA, Ribosomal/analysis , Microspheres , Polystyrenes , Water Pollution, Chemical
15.
FEMS Microbiol Ecol ; 40(2): 123-34, 2002 May 01.
Article in English | MEDLINE | ID: mdl-19709219

ABSTRACT

This study explored the geochemistry and microbial diversity of a Superfund site containing trichloroethene (TCE) and an unusual co-pollutant, tetrakis(2-ethylbutoxy)silane. Geochemical analysis of contaminated groundwater indicated subsurface anaerobiosis, reductive dechlorination of TCE to predominantly cis-1,2-dichloroethene, and (transient) accumulation of 2-ethylbutanol and 2-ethylbutyrate as a result of tetrakis(2-ethylbutoxy)silane breakdown. Comparative analysis of 106 16S rDNA and 61 16S-23S rDNA intergenic spacer region sequences - obtained from pristine and contaminated groundwater via DNA extraction, PCR amplification, cloning and sequencing - revealed that the contaminated groundwater featured (i) a distinct microbial community, (ii) reduced species diversity, (iii) various anaerobes, and (iv) bacteria closely related to the TCE-dechlorinating, dichloroethene-accumulating genus Dehalobacter, whereas (v) the TCE-dechlorinating, ethene-producing species Dehalococcoides ethenogenes was not detectable. Thus, geochemical and molecular biological results were in excellent agreement in this first ecological field study linking in situ reductive dechlorination of TCE to metabolism of tetraalkoxysilanes.

16.
Public Health Rep ; 102(4 Suppl): 140, 1987 Jul.
Article in English | MEDLINE | ID: mdl-19313191

ABSTRACT

This panel addressed five pertinent sets of questions involved in the communication process between women and their health care providers. Does gender really make a difference in health service delivery? Are health professionals taught adequate communication skills? Do communication barriers stem from the clinical setting itself? What are the most important barriers to effective communication with respect to women and particularly elderly women? Has there been progress in communication between patients and health care providers?

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