89 results on '"Tucker AL"'
Search Results
2. What Are Those Checkerboard Things?: How QR Codes Can Enrich Student Projects
- Author
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Tucker, Al
- Abstract
Students enrolled in commercial arts program design and publish their school's yearbook. For the 2010-2011 school year, the students applied Quick Response (QR) code technology to include links to events that occurred after the yearbook's print deadline, including graduation. The technology has many applications in the school setting, and the author offers this article as an inspiration for technology and engineering and career and technical educators. The author discusses how QR codes can enrich student projects.
- Published
- 2011
3. What Are Those Checkerboard Things? How Quick Response Codes Can Enrich Student Projects
- Author
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Tucker, Al
- Abstract
Students enrolled in the author's commercial arts program design and publish the school's yearbook. For the 2010-2011 school year, the students applied Quick Response (QR) code technology to include links to events that occurred after the yearbook's print deadline, including graduation. The technology has many applications in the school setting, and the author offers this article as an inspiration for technology and engineering and career and technical educators.
- Published
- 2011
4. Driving change: Defense financial management--results of 2006 survey
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Canter, Rhoda and Tucker, Al
- Subjects
FINANCE - Defense Dept - United States ,SURVEYS - Abstract
por
- Published
- 2006
5. Phospholemman does not participate in forskolin-induced swine carotid artery relaxation
- Author
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Meeks, MK, primary, Han, S, additional, Tucker, AL, additional, and Rembold, CM, additional
- Published
- 2008
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6. From the executive director
- Author
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Tucker, Al
- Subjects
Business ,Military and naval science - Abstract
The theme for this issue of Armed Forces Comptroller is 'The Future of Financial Management.' Our authors present a good cross section of people looking into the future, seeking a [...]
- Published
- 2009
7. Phospholemman-mediated activation of Na/K-ATPase limits [Na]i and inotropic state during beta-adrenergic stimulation in mouse ventricular myocytes.
- Author
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Despa S, Tucker AL, Bers DM, Despa, Sanda, Tucker, Amy L, and Bers, Donald M
- Published
- 2008
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8. An evaluation of the American Cancer Society research scholar program.
- Author
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Tucker AL, Vogler WR, Kepner JL, Tucker, Alyce L, Vogler, William R, and Kepner, James L
- Abstract
Background: The American Cancer Society (ACS) allocated competitive funding for Research Project Grants (RPG) to investigators and health care professionals early in their careers. This study explored the process of applying for an ACS grant and determined the differences, if any, in applicants that were funded and applicants that were not funded.Methods: Applicants applying for RPG funding in the spring of 1996 were sent a questionnaire.Results: Most variables between funded and unfunded applicants did not show significant differences. The perception of the application process varied significantly between groups.Conclusions: The application process of RPG was highly valued among funded applicants. [ABSTRACT FROM AUTHOR]- Published
- 2007
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9. Jubilee shouts
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Turrentine, Tommy (trompette); Horace Parlan (piano), George Tucker (Al Harewood (batterie) (faces 1 & 2); Tommy Turrentine (trompette), Kenny Burrel (guitare), Sonny Clark (piano), Butch Warren (contrebasse), Al Harewood (batterie) (faces 3 & 4), Turrentine, Stanley (saxophone ténor, faces 1-4, aussi parmi les compositeurs), Turrentine, Tommy (trompette); Horace Parlan (piano), George Tucker (Al Harewood (batterie) (faces 1 & 2); Tommy Turrentine (trompette), Kenny Burrel (guitare), Sonny Clark (piano), Butch Warren (contrebasse), Al Harewood (batterie) (faces 3 & 4), and Turrentine, Stanley (saxophone ténor, faces 1-4, aussi parmi les compositeurs)
- Abstract
Jazz: Instrumental, Palmaro Collections Pouchet
- Published
- 1978
10. Rocky mountain spotted fever with thrombocytopenia
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Tucker Al, Phillips Cw, Kimbrough Gt, and Weaver Ja
- Subjects
Aspirin ,business.industry ,medicine.drug_class ,Chloramphenicol ,Rocky Mountain spotted fever ,Antibiotics ,General Medicine ,Anorexia ,medicine.disease ,Measles ,Thrombocytopenic purpura ,Thrombocytopenia ,Immunology ,medicine ,Humans ,Headaches ,medicine.symptom ,business ,Rocky Mountain Spotted Fever ,medicine.drug - Published
- 1960
11. Skin markings on dark races
- Author
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Hardy Sb and Tucker Al
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medicine.medical_specialty ,business.industry ,Racial Groups ,medicine ,Humans ,Surgery ,Surgery, Plastic ,business ,Dermatology ,Plastics ,Skin Diseases - Published
- 1959
12. Gene expression profiling in the lungs of pigs with different susceptibilities to Glässer's disease
- Author
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Sargent Carole A, Wilkinson Jamie M, Galina-Pantoja Lucina, and Tucker Alexander W
- Subjects
Biotechnology ,TP248.13-248.65 ,Genetics ,QH426-470 - Abstract
Abstract Background Haemophilus parasuis is the causative agent of Glässer's disease in pigs. Currently, little is known about the molecular mechanisms that contribute to disease susceptibility. This study used a porcine oligonucleotide microarray to identify genes that were differentially expressed (DE) in the lungs of colostrum-deprived animals previously characterized as being either 'Fully Resistant' (FR) or 'Susceptible' to infection by H. parasuis in a bacterial challenge experiment. Results Gene expression profiles of 'FR' and 'Susceptible' animals were obtained by the identification of genes that were differentially expressed between each of these groups and mock-inoculated 'Control' animals. At 24 hours post-inoculation, a total of 21 and 58 DE genes were identified in 'FR' and 'Susceptible' animals respectively. At 72 hours, the numbers of genes were 20 and 347 respectively. 'FR' animals at 24 hours exhibited an increased expression of genes encoding extracellular matrix and TGF-β signalling components, possibly indicative of tissue repair following the successful early resolution of infection. The gene expression profile of 'FR' animals at 72 hours supported the hypothesis that higher levels of antibacterial activity were responsible for the 'FR' phenotype, possibly due to an increase in natural immunoglobulin A and decrease in signalling by the immunoregulatory transcription factor peroxisome proliferator-activated receptor gamma (PPAR-γ). The expression profile of 'Susceptible' animals at both time-points was characterized by an imbalance in signalling between pro and anti-inflammatory cytokines and an increased expression of genes involved in biological processes associated with inflammation. These include the pro-inflammatory cytokine genes resistin (RETN) and interleukin 1-beta (IL1B). At 72 hours, a reduction in the expression of genes involved in antigen presentation by both MHC class I and II molecules was observed, which could have contributed to the inability of 'Susceptible' animals to clear infection. Conclusions This study is the first to have identified discrete sets of DE genes in pigs of differing susceptibility to H. parasuis infection. Consequently, several candidate genes and pathways for disease resistance or susceptibility phenotypes have been identified. In addition, the findings have shed light on the molecular pathology associated with Glässer's disease.
- Published
- 2010
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13. The identification of informative genes from multiple datasets with increasing complexity
- Author
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't Hoen Peter AC, Anvar S Yahya, and Tucker Allan
- Subjects
Computer applications to medicine. Medical informatics ,R858-859.7 ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background In microarray data analysis, factors such as data quality, biological variation, and the increasingly multi-layered nature of more complex biological systems complicates the modelling of regulatory networks that can represent and capture the interactions among genes. We believe that the use of multiple datasets derived from related biological systems leads to more robust models. Therefore, we developed a novel framework for modelling regulatory networks that involves training and evaluation on independent datasets. Our approach includes the following steps: (1) ordering the datasets based on their level of noise and informativeness; (2) selection of a Bayesian classifier with an appropriate level of complexity by evaluation of predictive performance on independent data sets; (3) comparing the different gene selections and the influence of increasing the model complexity; (4) functional analysis of the informative genes. Results In this paper, we identify the most appropriate model complexity using cross-validation and independent test set validation for predicting gene expression in three published datasets related to myogenesis and muscle differentiation. Furthermore, we demonstrate that models trained on simpler datasets can be used to identify interactions among genes and select the most informative. We also show that these models can explain the myogenesis-related genes (genes of interest) significantly better than others (P < 0.004) since the improvement in their rankings is much more pronounced. Finally, after further evaluating our results on synthetic datasets, we show that our approach outperforms a concordance method by Lai et al. in identifying informative genes from multiple datasets with increasing complexity whilst additionally modelling the interaction between genes. Conclusions We show that Bayesian networks derived from simpler controlled systems have better performance than those trained on datasets from more complex biological systems. Further, we present that highly predictive and consistent genes, from the pool of differentially expressed genes, across independent datasets are more likely to be fundamentally involved in the biological process under study. We conclude that networks trained on simpler controlled systems, such as in vitro experiments, can be used to model and capture interactions among genes in more complex datasets, such as in vivo experiments, where these interactions would otherwise be concealed by a multitude of other ongoing events.
- Published
- 2010
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14. Nudging Healthier Choices in a Hospital Cafeteria: Results From a Field Study.
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Mazza MC, Dynan L, Siegel RM, and Tucker AL
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- Beverages, Food Service, Hospital standards, Humans, Obesity, Choice Behavior, Feeding Behavior, Food Labeling methods, Food Service, Hospital organization & administration, Workplace
- Abstract
More than two thirds of adults and one third of children are overweight or obese in the United States. These trends have led to initiatives to provide information that supports informed choices. Traffic light labeling has been shown to increase consumer awareness and encourage healthy selections. This article contributes to the literature on healthy choices by comparing the additional contribution of a number of interventions used in combination with traffic light labeling. We conducted a 21-month field study in a workplace cafeteria. We analyzed cash register receipts, focusing on sales of beverages and chips. We found that the traffic light system was effective. The addition of caloric information to traffic light labeling had a positive effect on the purchase of healthy chips. However, other interventions appeared to produce more harm than good, essentially wiping out the benefits from traffic light labeling. These findings suggest that although it is possible to improve on traffic light labeling with selective interventions, caution is in order as some interventions may trigger compensatory behavior that results in the purchase of unhealthy items.
- Published
- 2018
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15. The impact of middle manager affective commitment on perceived improvement program implementation success.
- Author
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Fryer AK, Tucker AL, and Singer SJ
- Subjects
- Adult, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, Nurse Administrators organization & administration, Organizational Culture, Surveys and Questionnaires, Implementation Science, Leadership, Nurse Administrators psychology, Quality Improvement organization & administration
- Abstract
Background: Recent literature suggests that middle manager affective commitment (emotional attachment, identification, and involvement) to an improvement program may influence implementation success. However, less is known about the interplay between middle manager affective commitment and frontline worker commitment, another important driver of implementation success., Purpose: We contribute to this research by surveying middle managers who directly manage frontline workers on nursing units. We assess how middle manager affective commitment is related to their perceptions of implementation success and whether their perceptions of frontline worker support mediate this relationship. We also test whether a set of organizational support factors foster middle manager affective commitment., Methodology: We adapt survey measures of manager affective commitment to our research context of hospitals. We surveyed 67 nurse managers from 19 U.S. hospitals. We use hierarchical linear regression to assess relationships among middle manager affective commitment to their units' falls reduction program and their perceptions of three constructs related to the program: frontline worker support, organizational support, and implementation success., Results: Middle manager affective commitment to their unit's falls reduction program is positively associated with their perception of implementation success. This relationship is mediated by their perception of frontline worker support for the falls program. Moreover, middle managers' affective commitment to their unit's falls program mediates the relationship between perceived organizational support for the program and perceived implementation success., Conclusion: We, through this research, offer an important contribution by providing empirical support of factors that may influence successful implementation of an improvement program: middle manager affective commitment, frontline worker support, and organizational support for an improvement program., Practice Implications: Increasing levels of middle manager affective commitment to an improvement program could strengthen program implementation success by facilitating frontline worker support for the program. Furthermore, providing the organizational support items in our survey construct may bolster middle manager affective commitment.
- Published
- 2018
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16. Multidisciplinary Clinic to Identify Near Misses and Decrease Readmission Rates After Hospitalization for Myocardial Infarction.
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Cornielle-Caamano VM, Salerno M, Millard MA, Loguidice MJ, Lawlor BT, Shah IT, Chidester JP, Alhajri FH, Aktan I, Blakeney AK, Fauber NM, Ward KK, Tucker AL, and Keeley EC
- Subjects
- Health Status, Humans, Myocardial Infarction diagnosis, Myocardial Infarction mortality, Patient Care Team, Program Development, Program Evaluation, Quality Improvement, Quality Indicators, Health Care, Risk Factors, Time Factors, Treatment Outcome, Myocardial Infarction therapy, Near Miss, Healthcare, Patient Discharge, Patient Readmission
- Published
- 2017
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17. Applying Organizational Learning Research to Accountable Care Organizations.
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Nembhard IM and Tucker AL
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- Continuity of Patient Care organization & administration, Humans, Medicare organization & administration, Quality of Health Care organization & administration, Risk Sharing, Financial, United States, Accountable Care Organizations organization & administration, Cooperative Behavior, Learning, Organizational Culture
- Abstract
To accomplish the goal of improving quality of care while simultaneously reducing cost, Accountable Care Organizations (ACOs) need to find new and better ways of providing health care to populations of patients. This requires implementing best practices and improving collaboration across the multiple entities involved in care delivery, including patients. In this article, we discuss seven lessons from the organizational learning literature that can help ACOs overcome the inherent challenges of learning how to work together in radically new ways. The lessons involve setting expectations, creating a supportive culture, and structuring the improvement efforts. For example, with regard to setting expectations, framing the changes as learning experiences rather than as implementation projects encourages the teams to utilize helpful activities, such as dry runs and pilot tests. It is also important to create an organizational culture where employees feel safe pointing out improvement opportunities and experimenting with new ways of working. With regard to structure, stable, cross-functional teams provide a powerful building block for effective improvement efforts. The article concludes by outlining opportunities for future research on organizational learning in ACOs., (© The Author(s) 2016.)
- Published
- 2016
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18. Multidomain, Surface Layer-associated Glycoside Hydrolases Contribute to Plant Polysaccharide Degradation by Caldicellulosiruptor Species.
- Author
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Conway JM, Pierce WS, Le JH, Harper GW, Wright JH, Tucker AL, Zurawski JV, Lee LL, Blumer-Schuette SE, and Kelly RM
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- Bacterial Proteins chemistry, Bacterial Proteins genetics, Cloning, Molecular, Clostridiales chemistry, Clostridiales classification, Escherichia coli genetics, Escherichia coli metabolism, Gene Expression, Glucans metabolism, Glycoside Hydrolases chemistry, Glycoside Hydrolases genetics, Kinetics, Mutation, Phylogeny, Polysaccharides metabolism, Protein Binding, Protein Engineering, Protein Structure, Tertiary, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins metabolism, Substrate Specificity, Xylans metabolism, Bacterial Proteins metabolism, Clostridiales enzymology, Genome, Bacterial, Glycoside Hydrolases metabolism, Wood metabolism
- Abstract
The genome of the extremely thermophilic bacterium Caldicellulosiruptor kronotskyensisencodes 19 surface layer (S-layer) homology (SLH) domain-containing proteins, the most in any Caldicellulosiruptorspecies genome sequenced to date. These SLH proteins include five glycoside hydrolases (GHs) and one polysaccharide lyase, the genes for which were transcribed at high levels during growth on plant biomass. The largest GH identified so far in this genus, Calkro_0111 (2,435 amino acids), is completely unique toC. kronotskyensisand contains SLH domains. Calkro_0111 was produced recombinantly inEscherichia colias two pieces, containing the GH16 and GH55 domains, respectively, as well as putative binding and spacer domains. These displayed endo- and exoglucanase activity on the β-1,3-1,6-glucan laminarin. A series of additional truncation mutants of Calkro_0111 revealed the essential architectural features required for catalytic function. Calkro_0402, another of the SLH domain GHs inC. kronotskyensis, when produced inE. coli, was active on a variety of xylans and β-glucans. Unlike Calkro_0111, Calkro_0402 is highly conserved in the genus Caldicellulosiruptorand among other biomass-degrading Firmicutes but missing from Caldicellulosiruptor bescii As such, the gene encoding Calkro_0402 was inserted into the C. besciigenome, creating a mutant strain with its S-layer extensively decorated with Calkro_0402. This strain consequently degraded xylans more extensively than wild-typeC. bescii The results here provide new insights into the architecture and role of SLH domain GHs and demonstrate that hemicellulose degradation can be enhanced through non-native SLH domain GHs engineered into the genomes of Caldicellulosiruptorspecies., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)
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- 2016
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19. Incidence rate of pathogen-specific clinical mastitis on conventional and organic Canadian dairy farms.
- Author
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Levison LJ, Miller-Cushon EK, Tucker AL, Bergeron R, Leslie KE, Barkema HW, and DeVries TJ
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- Animals, Cattle, Cell Count veterinary, Dairying, Female, Incidence, Lactation, Mastitis, Bovine microbiology, Ontario epidemiology, Organic Agriculture, Species Specificity, Bacillus isolation & purification, Escherichia coli isolation & purification, Mastitis, Bovine epidemiology, Milk metabolism, Staphylococcus isolation & purification
- Abstract
Mastitis is a common and costly production disease on dairy farms. In Canada, the incidence rate of clinical mastitis (IRCM) has been determined for conventionally managed dairy farms; however, no studies to date have assessed rates in organically managed systems. The objectives of this observational study were (1) to determine the producer-reported IRCM and predominant pathogen types on conventional and organic dairy farms in Southern Ontario, Canada, and (2) to evaluate the association of both mean overall IRCM and pathogen-specific IRCM with management system, housing type, and pasture access. Data from 59 dairy farms in Southern Ontario, Canada, distributed across conventional (n=41) and organic management (n=18) systems, were collected from April 2011 to May 2012. In addition to management system, farms were categorized by housing method (loose or tie-stall) and pasture access for lactating cows. Participating producers identified and collected samples from 936 cases of clinical mastitis. The most frequently isolated mastitis pathogens were coagulase-negative staphylococci, Bacillus spp., Streptococcus spp., Staphylococcus aureus, and Escherichia coli. The IRCM was higher on conventional farms than organic (23.7 vs. 13.2 cases per 100 cow-years) and was not associated with housing type (loose or tie-stall), pasture access, or herd-average milk yield. Bulk tank somatic cell count tended to be lower on conventional farms than organic (222,000 vs. 272,000 cells/mL). Pathogen-specific IRCM attributed to Staph. aureus, Bacillus spp., and E. coli was greater on conventional than organic farms, but was not associated with housing or any other factors. In conclusion, organic management was associated with reduced overall and pathogen-specific IRCM., (Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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20. Spider crabs of the Western Atlantic with special reference to fossil and some modern Mithracidae.
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Klompmaker AA, Portell RW, Klier AT, Prueter V, and Tucker AL
- Abstract
Spider crabs (Majoidea) are well-known from modern oceans and are also common in the western part of the Atlantic Ocean. When spider crabs appeared in the Western Atlantic in deep time, and when they became diverse, hinges on their fossil record. By reviewing their fossil record, we show that (1) spider crabs first appeared in the Western Atlantic in the Late Cretaceous, (2) they became common since the Miocene, and (3) most species and genera are found in the Caribbean region from the Miocene onwards. Furthermore, taxonomic work on some modern and fossil Mithracidae, a family that might have originated in the Western Atlantic, was conducted. Specifically, Maguimithrax gen. nov. is erected to accommodate the extant species Damithrax spinosissimus, while Damithrax cf. pleuracanthus is recognized for the first time from the fossil record (late Pliocene-early Pleistocene, Florida, USA). Furthermore, two new species are described from the lower Miocene coral-associated limestones of Jamaica (Mithrax arawakum sp. nov. and Nemausa windsorae sp. nov.). Spurred by a recent revision of the subfamily, two known species from the same deposits are refigured and transferred to new genera: Mithrax donovani to Nemausa, and Mithrax unguis to Damithrax. The diverse assemblage of decapods from these coral-associated limestones underlines the importance of reefs for the abundance and diversity of decapods in deep time. Finally, we quantitatively show that these crabs possess allometric growth in that length/width ratios drop as specimens grow, a factor that is not always taken into account while describing and comparing among taxa.
- Published
- 2015
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21. Regulation of L-type calcium channel by phospholemman in cardiac myocytes.
- Author
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Zhang XQ, Wang J, Song J, Rabinowitz J, Chen X, Houser SR, Peterson BZ, Tucker AL, Feldman AM, and Cheung JY
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- Adenoviridae metabolism, Amino Acid Motifs, Animals, Cells, Cultured, Cytoplasm chemistry, Dogs, Heart Ventricles drug effects, Heart Ventricles metabolism, Ion Channel Gating drug effects, Isoproterenol pharmacology, Membrane Proteins chemistry, Mice, Mice, Inbred C57BL, Mice, Knockout, Mutant Proteins metabolism, Myocytes, Cardiac drug effects, Phosphoproteins chemistry, Phosphoserine metabolism, Protein Structure, Tertiary, Structure-Activity Relationship, Calcium Channels, L-Type metabolism, Membrane Proteins metabolism, Myocytes, Cardiac metabolism, Phosphoproteins metabolism
- Abstract
We evaluated whether phospholemman (PLM) regulates L-type Ca(2+) current (ICa) in mouse ventricular myocytes. Expression of α1-subunit of L-type Ca(2+) channels between wild-type (WT) and PLM knockout (KO) hearts was similar. Compared to WT myocytes, peak ICa (at -10 mV) from KO myocytes was ~41% larger, the inactivation time constant (τ(inact)) of ICa was ~39% longer, but deactivation time constant (τ(deact)) was similar. In the presence of isoproterenol (1 μM), peak ICa was ~48% larger and τ(inact) was ~144% higher in KO myocytes. With Ba(2+) as the permeant ion, PLM enhanced voltage-dependent inactivation but had no effect on τ(deact). To dissect the molecular determinants by which PLM regulated ICa, we expressed PLM mutants by adenovirus-mediated gene transfer in cultured KO myocytes. After 24h in culture, KO myocytes expressing green fluorescent protein (GFP) had significantly larger peak ICa and longer τ(inact) than KO myocytes expressing WT PLM; thereby independently confirming the observations in freshly isolated myocytes. Compared to KO myocytes expressing GFP, KO myocytes expressing the cytoplasmic domain truncation mutant (TM43), the non-phosphorylatable S68A mutant, the phosphomimetic S68E mutant, and the signature PFXYD to alanine (ALL5) mutant all resulted in lower peak ICa. Expressing PLM mutants did not alter expression of α1-subunit of L-type Ca(2+) channels in cultured KO myocytes. Our results suggested that both the extracellular PFXYD motif and the transmembrane domain of PLM but not the cytoplasmic tail were necessary for regulation of peak ICa amplitude. We conclude that PLM limits Ca(2+) influx in cardiac myocytes by reducing maximal ICa and accelerating voltage-dependent inactivation., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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22. Adult humans' understanding of support relations: an up-linkage replication.
- Author
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Silva FJ, Ten Hope MI, and Tucker AL
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- Humans, Photic Stimulation, Visual Perception physiology, Attention physiology, Cognition physiology, Comprehension physiology
- Abstract
In an up-linkage replication, three experiments examined adult humans' folk physics, i.e., their naturally occurring and spontaneous understanding of the physical world, using a violation of expectation (VOE) task and stimuli similar to those used to study chimpanzees', monkeys', and rooks' folk physics. Unlike what has been reported with nonhuman primates, adult humans did not look longer at physically impossible than possible events, though they did rate the physically impossible events as more interesting and novel than the possible events. These results underscore that behavior during a VOE experiment has many possible causes, only one of which may be a subject's folk physics.
- Published
- 2014
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23. The evolving literature on safety WalkRounds: emerging themes and practical messages.
- Author
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Singer SJ and Tucker AL
- Subjects
- Humans, Leadership, Organizational Culture, Patient Safety, Quality Assurance, Health Care, Safety Management
- Published
- 2014
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24. Process improvements and shared medical appointments for cardiovascular disease prevention in women.
- Author
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Pastore LM, Rossi AM, and Tucker AL
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- Female, Group Processes, Humans, United States, Appointments and Schedules, Cardiovascular Diseases prevention & control, Disease Management, Patient Satisfaction, Process Assessment, Health Care methods
- Abstract
Problem: Cardiovascular disease (CVD) is clinically unique in women and is often underdiagnosed and undertreated. Chronic diseases account for 75% of healthcare expenditures in the United States, of which 70% are preventable through lifestyle changes and active medical management. Lifestyle modification is difficult in the context of the traditional medical visit., Design: The Club Red Clinic uses a novel approach to enhance the care of women at risk for or with CVD. Through shared medical appointments (SMAs) and a multidisciplinary team approach, Club Red provides lifestyle training in addition to evidence-based practice to reduce CVD risk factors in women. In Club Red, nurse practitioners function independently and effectively in delivering lifestyle intervention for the management and prevention of CVD., Setting: The clinic functions within an academic medical school at the University of Virginia., Key Measures for Improvement: Patient access, patient satisfaction, provider efficiency, and frequency of cardiovascular visits., Effects of Change: Process improvements include reduced appointment wait times, improved provider efficiency (more patients seen with the SMAs), high patient satisfaction (96%), and improved adherence to recommended medical monitoring (3.8 visits/year)., Lessons Learned: Club Red improved patient access, patient satisfaction, medical and behavioral management, and health promotion education for women with or at risk for CVD., (©2013 American Association of Nurse Practitioners.)
- Published
- 2014
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25. Designed for workarounds: a qualitative study of the causes of operational failures in hospitals.
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Tucker AL, Heisler WS, and Janisse LD
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- Equipment and Supplies standards, Humans, Interdepartmental Relations, Qualitative Research, Surveys and Questionnaires, Efficiency, Organizational, Hospital Administration standards
- Abstract
Frontline care clinicians and staff in hospitals spend at least 10% of their time working around operational failures: situations in which information, supplies, or equipment needed for patient care are insufficient. However, little is known about underlying causes of operational failures and what hospitals can do to reduce their occurrence. To address this gap, we examined the internal supply chains at 2 hospitals with the aim of discovering organizational factors that contribute to operational failures. We conducted in-depth qualitative research, including observations and interviews of more than 80 individuals from 4 nursing units and the ancillary support departments that provide equipment and supplies needed for patient care. We found that a lack of interconnectedness among interdependent departments' routines was a major source of operational failures. The low levels of interconnectedness occurred because of how the internal supply chains were designed and managed rather than because of employee error or a shortfall in training. Thus, we propose that the time that hospital staff members spend on workarounds can be reduced through deliberate efforts to increase interconnectedness among hospitals' internal supply departments. Four dimensions of interconnectedness include: 1) hospital-level-rather than department-level-performance measures; 2) internal supply department routines that respond to specific patients' needs rather than to predetermined stocking routines; 3) knowledge that is necessary for efficient handoffs of materials that is translated across departmental boundaries; and 4) cross-departmental collaboration mechanisms that enable improvement in the flow of materials across departmental boundaries.
- Published
- 2014
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26. Risk of first-time heart disease higher for hormone therapy users with metabolic syndrome.
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Pinkerton JV, Pastore LM, Johns DW, and Tucker AL
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- Female, Humans, Coronary Disease epidemiology, Metabolic Syndrome complications, Women's Health
- Published
- 2013
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27. Phospholemman deficiency in postinfarct hearts: enhanced contractility but increased mortality.
- Author
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Mirza MA, Lane S, Yang Z, Karaoli T, Akosah K, Hossack J, McDuffie M, Wang J, Zhang XQ, Song J, Cheung JY, and Tucker AL
- Subjects
- Animals, Calcium Signaling, Cell Size, Heart Function Tests, Ion Channel Gating, Membrane Proteins metabolism, Mice, Mice, Inbred C57BL, Mice, Knockout, Models, Cardiovascular, Myocardial Infarction diagnostic imaging, Myocardial Infarction pathology, Myocytes, Cardiac pathology, Organ Size, Phosphoproteins metabolism, Phosphorylation, Sodium-Potassium-Exchanging ATPase metabolism, Survival Analysis, Ultrasonography, Membrane Proteins deficiency, Myocardial Contraction physiology, Myocardial Infarction metabolism, Myocardial Infarction physiopathology, Myocardium metabolism, Myocardium pathology, Phosphoproteins deficiency
- Abstract
Phospholemman (PLM) regulates [Na(+) ](i), [Ca(2+)](i) and contractility through its interactions with Na(+)-K(+)-ATPase (NKA) and Na(+) /Ca(2+) exchanger (NCX1) in the heart. Both expression and phosphorylation of PLM are altered after myocardial infarction (MI) and heart failure. We tested the hypothesis that absence of PLM regulation of NKA and NCX1 in PLM-knockout (KO) mice is detrimental. Three weeks after MI, wild-type (WT) and PLM-KO hearts were similarly hypertrophied. PLM expression was lower but fractional phosphorylation was higher in WT-MI compared to WT-sham hearts. Left ventricular ejection fraction was severely depressed in WT-MI but significantly less depressed in PLM-KO-MI hearts despite similar infarct sizes. Compared with WT-sham myocytes, the abnormal [Ca(2+) ], transient and contraction amplitudes observed in WT-MI myocytes were ameliorated by genetic absence of PLM. In addition, NCX1 current was depressed in WT-MI but not in PLM-KO-MI myocytes. Despite improved myocardial and myocyte performance, PLM-KO mice demonstrated reduced survival after MI. Our findings indicate that alterations in PLM expression and phosphorylation are important adaptations post-MI, and that complete absence of PLM regulation of NKA and NCX1 is detrimental in post-MI animals., (© 2012 Wiley Periodicals, Inc.)
- Published
- 2012
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28. Effect of in-water iodine supplementation on weight gain, diarrhea and oral and dental health of nursery pigs.
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Tucker AL, Farzan A, Cassar G, and Friendship RM
- Subjects
- Animals, Diarrhea prevention & control, Dietary Supplements, Female, Iodine chemistry, Male, Mouth Diseases prevention & control, Swine, Tooth Diseases prevention & control, Water chemistry, Diarrhea veterinary, Iodine pharmacology, Mouth Diseases veterinary, Swine Diseases prevention & control, Tooth Diseases veterinary, Weight Gain drug effects
- Abstract
A farm trial was conducted to evaluate the effect of in-water iodine on piglet growth, the incidence of diarrhea, and the development of deleterious oral and dental conditions. A total of 208 weaned piglets were included in the study. Piglets were weighed 3 times: within 24 h of weaning, and 3 wk and 6 wk after weaning. A concentration of 1 ppm iodine was provided in their drinking water. Swabs were taken from all water nipples and water lines and pooled fecal samples were collected from all pen floors. Fecal samples were also collected from sows at weaning. The swabs and fecal samples were tested for the presence of Salmonella and Escherichia coli. Within 24 h of each weighing, a complete oral examination was performed on each piglet. No significant difference in growth (P > 0.05) or dental conditions (P > 0.05) was found among treatment groups during the period that iodine was added to the drinking water. After weaning, all deleterious oral conditions increased (oral lesions from weaning to 6 wk, staining and caries from weaning to 3 wk, gingivitis from 3 wk to 6 wk; P < 0.05). Only gingivitis was found to be negatively associated with piglet weight (P < 0.05). Salmonella was cultured only twice from fecal samples and never from water nipples. Only 1 sow tested positive for Salmonella and E. coli O139: K82 and O157:K"V17 were cultured only rarely from the water nipples. No signs of diarrhea were noted throughout the study. Adding an aqueous iodine supplement to nursery pigs, therefore, did not provide an advantage for either growth or oral condition. Deleterious oral conditions do increase after weaning, with gingivitis being associated with lower piglet weight.
- Published
- 2011
29. Regulation of in vivo cardiac contractility by phospholemman: role of Na+/Ca2+ exchange.
- Author
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Wang J, Gao E, Rabinowitz J, Song J, Zhang XQ, Koch WJ, Tucker AL, Chan TO, Feldman AM, and Cheung JY
- Subjects
- Animals, Cardiotonic Agents pharmacology, Cells, Cultured, Heart drug effects, Heart physiology, Isoproterenol pharmacology, Membrane Potentials drug effects, Membrane Potentials physiology, Membrane Proteins metabolism, Mice, Mice, Inbred C57BL, Mice, Knockout, Myocardial Contraction drug effects, Myocytes, Cardiac drug effects, Myocytes, Cardiac physiology, Phosphoproteins metabolism, Sarcoplasmic Reticulum Calcium-Transporting ATPases metabolism, Sarcoplasmic Reticulum Calcium-Transporting ATPases physiology, Sodium-Calcium Exchanger metabolism, Sodium-Potassium-Exchanging ATPase metabolism, Sodium-Potassium-Exchanging ATPase physiology, Membrane Proteins physiology, Myocardial Contraction physiology, Phosphoproteins physiology, Sodium-Calcium Exchanger physiology
- Abstract
Phospholemman (PLM), when phosphorylated at serine 68, relieves its inhibition on Na(+)-K(+)-ATPase but inhibits Na(+)/Ca(2+) exchanger 1 (NCX1) in cardiac myocytes. Under stress when catecholamine levels are high, enhanced Na(+)-K(+)-ATPase activity by phosphorylated PLM attenuates intracellular Na(+) concentration ([Na(+)](i)) overload. To evaluate the effects of PLM on NCX1 on in vivo cardiac contractility, we injected recombinant adeno-associated virus (serotype 9) expressing either the phosphomimetic PLM S68E mutant or green fluorescent protein (GFP) directly into left ventricles (LVs) of PLM-knockout (KO) mice. Five weeks after virus injection, ∼40% of isolated LV myocytes exhibited GFP fluorescence. Expression of S68E mutant was confirmed with PLM antibody. There were no differences in protein levels of α(1)- and α(2)-subunits of Na(+)-K(+)-ATPase, NCX1, and sarco(endo)plasmic reticulum Ca(2+)-ATPase between KO-GFP and KO-S68E LV homogenates. Compared with KO-GFP myocytes, Na(+)/Ca(2+) exchange current was suppressed, but resting [Na(+)](i), Na(+)-K(+)-ATPase current, and action potential amplitudes were similar in KO-S68E myocytes. Resting membrane potential was slightly lower and action potential duration at 90% repolarization (APD(90)) was shortened in KO-S68E myocytes. Isoproterenol (Iso; 1 μM) increased APD(90) in both groups of myocytes. After Iso, [Na(+)](i) increased monotonically in paced (2 Hz) KO-GFP but reached a plateau in KO-S68E myocytes. Both systolic and diastolic [Ca(2+)](i) were higher in Iso-stimulated KO-S68E myocytes paced at 2 Hz. Echocardiography demonstrated similar resting heart rate, ejection fraction, and LV mass between KO-GFP and KO-S68E mice. In vivo closed-chest catheterization demonstrated enhanced contractility in KO-S68E compared with KO-GFP hearts stimulated with Iso. We conclude that under catecholamine stress when [Na(+)](i) is high, PLM minimizes [Na(+)](i) overload by relieving its inhibition of Na(+)-K(+)-ATPase and preserves inotropy by simultaneously inhibiting Na(+)/Ca(2+) exchanger.
- Published
- 2011
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30. The effect of dentition on feeding development in piglets and on their growth and behavior after weaning.
- Author
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Tucker AL, Duncan IJ, Millman ST, Friendship RM, and Widowski TM
- Subjects
- Animal Feed, Animals, Animals, Newborn physiology, Bicuspid growth & development, Body Weight physiology, Eating physiology, Swine physiology, Tooth Eruption physiology, Weaning, Dentition, Feeding Behavior physiology, Swine growth & development
- Abstract
The objectives of this study were to determine the effects of dentition on feed-oriented behavior and feed consumption before weaning at 28 d, and whether premolar eruption or occlusion at the time of weaning influenced postweaning growth or behavior. Over 3 trials, 24 litters of Yorkshire piglets (n = 233) were provided with creep feed marked with 1% chromic oxide on d 5. Dental exams were performed on d 2, 6, 9, 13, 16, 20, 23, and 27. Fecal samples were visually assessed for feed consumption (via fecal color) on the same day as dental exams, beginning on d 6. The duration of time spent at, and frequency of visits to, the creep feeder were determined from continuous video recordings on d 7, 10, 14, 17, 21, and 24 for 6 h/d (0700 to 1000 h, 1300 to 1600 h). After weaning, behavior was recorded every 5 min for three 2-h time periods (0600 to 0800 h, 1100 to 1300 h, and 1600 to 1800 h) on d 2, 4, 6, 8, 10, and 12. Piglets younger than 17 d with their premolars erupted and occluded spent less time at the creep feeder and visited it less often than piglets without their premolars erupted and occluded [duration: p(3) (premolar position 3 on maxilla), d 7 (P = 0.005); p(4) (premolar position 4 on mandible), d 7 (P < 0.0001), d 10 (P = 0.003); p(4 )(premolar position 4 on maxilla), d 17 (P = 0.012); occlusion, d 7 (P < 0.0001), d 10 (P = 0.0004); visits: p(3), d 7 (P < 0.0001); p(4), d 7 (P < 0.0001), d 10 (P = 0.001); p(3 )(premolar position 3 on mandible), d 14 (P = 0.037); p(4), d 17 (P = 0.024); occlusion, d 7 (P < 0.0001), d 10 (P = 0.003)]. By d 21 of age, this trend reversed such that piglets with premolars erupted and occluded spent more time at the feeder and visited it more frequently [duration: p(3), d 24 (P = 0.025); p(4), d 24 (P = 0.0005); occlusion, d 21 (P = 0.001), d 24 (P = 0.0001); visits: p(3), d 21 (P = 0.0002), d 24 (P < 0.0001); p(4), d 24 (P = 0.0002); occlusion, d 21 (P < 0.0001), d 24 (P < 0.0001)]. The percentages of piglets with positive fecal scores were 0, 1.4, 4.6, 8.0, 29.0, 44.9, and 60.6% on d 7, 10, 14, 17, 21, 24, and 27, respectively (P < 0.0001 between each day). No associations were found between the eruption or occlusion of premolars and feed consumption before weaning (P > 0.05), and no dental measures influenced growth rates (P > 0.10) or behavior (P > 0.10) after weaning. A more precise method may be necessary for detecting associations between dental eruption and feed consumption. However, the behavioral results indicate that, before weaning at 28 d, younger piglets are inhibited from feeding when their premolars first erupt, whereas older piglets with a more advanced dentition are more attracted to feed.
- Published
- 2010
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31. Metabolic indicators of nutritional stress are not predictive of abnormal oral behavior in piglets.
- Author
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Tucker AL, Atkinson JL, Millman ST, and Widowski TM
- Subjects
- 3-Hydroxybutyric Acid blood, Animals, Blood Glucose analysis, Drinking, Eating, Fatty Acids, Nonesterified blood, Mouth physiology, Nose physiology, Predictive Value of Tests, Stress, Physiological, Weaning, Weight Gain, Animals, Newborn physiology, Behavior, Animal physiology, Food Deprivation physiology, Health Status Indicators, Swine physiology, Swine psychology
- Abstract
Belly nosing is an abnormal oral-nasal behavior that can develop to high levels in newly weaned piglets and may signal nutritional need. The effects of feed restriction on both behavior and metabolic serum parameters were examined in 128 weaned piglets. All pigs were fed ad libitum during week 1, and during week 2, half of all pens (N=8) were restricted to 65% of ad libitum intake. Blood samples were collected on days 3 and 10 after weaning and behavior was observed from video recordings on days 5 and 12. Piglets were classified as early 'nosers' or early 'non-nosers' based on their behavior on day 5. Feed restriction resulted in elevated non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB) and both lower glucose and a NEFA/glucose ratio, but belly nosing was not affected. Piglets classified as 'nosers' did not have blood profiles indicating they were in greater nutritional need compared to 'non-nosers' in the first week of weaning, nor did they increase belly nosing or other piglet directed behaviors when restricted in week 2. Overall, no associations were found between blood parameters indicative of nutritional stress and belly nosing. This study identifies serum glucose, BHB and NEFA as well as the glucose/NEFA ratio as useful indicators of nutritional stress in newly weaned piglets., ((c) 2010 Elsevier Inc. All rights reserved.)
- Published
- 2010
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32. Phospholemman and beta-adrenergic stimulation in the heart.
- Author
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Wang J, Gao E, Song J, Zhang XQ, Li J, Koch WJ, Tucker AL, Philipson KD, Chan TO, Feldman AM, and Cheung JY
- Subjects
- Adrenergic beta-Agonists pharmacology, Animals, Calcium metabolism, Cells, Cultured, Heart drug effects, Isoproterenol pharmacology, Membrane Proteins genetics, Mice, Mice, Inbred C57BL, Mice, Knockout, Models, Animal, Myocardial Contraction drug effects, Myocardium cytology, Myocytes, Cardiac cytology, Myocytes, Cardiac drug effects, Phosphoproteins genetics, Sodium-Calcium Exchanger metabolism, Sodium-Potassium-Exchanging ATPase metabolism, Membrane Proteins metabolism, Myocardium metabolism, Myocytes, Cardiac metabolism, Phosphoproteins metabolism, Receptors, Adrenergic, beta metabolism
- Abstract
Phosphorylation at serine 68 of phospholemman (PLM) in response to beta-adrenergic stimulation results in simultaneous inhibition of cardiac Na(+)/Ca(2+) exchanger NCX1 and relief of inhibition of Na(+)-K(+)-ATPase. The role of PLM in mediating beta-adrenergic effects on in vivo cardiac function was investigated with congenic PLM-knockout (KO) mice. Echocardiography showed similar ejection fraction between wild-type (WT) and PLM-KO hearts. Cardiac catheterization demonstrated higher baseline contractility (+dP/dt) but similar relaxation (-dP/dt) in PLM-KO mice. In response to isoproterenol (Iso), maximal +dP/dt was similar but maximal -dP/dt was reduced in PLM-KO mice. Dose-response curves to Iso (0.5-25 ng) for WT and PLM-KO hearts were superimposable. Maximal +dP/dt was reached 1-2 min after Iso addition and declined with time in WT but not PLM-KO hearts. In isolated myocytes paced at 2 Hz. contraction and intracellular Ca(2+) concentration ([Ca(2+)](i)) transient amplitudes and [Na(+)](i) reached maximum 2-4 min after Iso addition, followed by decline in WT but not PLM-KO myocytes. Reducing pacing frequency to 0.5 Hz resulted in much smaller increases in [Na(+)](i) and no decline in contraction and [Ca(2+)](i) transient amplitudes with time in Iso-stimulated WT and PLM-KO myocytes. Although baseline Na(+)-K(+)-ATPase current was 41% higher in PLM-KO myocytes because of increased alpha(1)- but not alpha(2)-subunit activity, resting [Na(+)](i) was similar between quiescent WT and PLM-KO myocytes. Iso increased alpha(1)-subunit current (I(alpha1)) by 73% in WT but had no effect in PLM-KO myocytes. Iso did not affect alpha(2)-subunit current (I(alpha2)) in WT and PLM-KO myocytes. In both WT and NCX1-KO hearts, PLM coimmunoprecipitated with Na(+)-K(+)-ATPase alpha(1)- and alpha(2)-subunits, indicating that association of PLM with Na(+)-K(+)-ATPase did not require NCX1. We conclude that under stressful conditions in which [Na(+)](i) was high, beta-adrenergic agonist-mediated phosphorylation of PLM resulted in time-dependent reduction in inotropy due to relief of inhibition of Na(+)-K(+)-ATPase.
- Published
- 2010
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33. Health Heritage© a web-based tool for the collection and assessment of family health history: initial user experience and analytic validity.
- Author
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Cohn WF, Ropka ME, Pelletier SL, Barrett JR, Kinzie MB, Harrison MB, Liu Z, Miesfeldt S, Tucker AL, Worrall BB, Gibson J, Mullins IM, Elward KS, Franko J, Guterbock TM, and Knaus WA
- Subjects
- Adolescent, Adult, Aged, Female, Health Behavior, Humans, Male, Middle Aged, Population Surveillance, Risk Assessment, Software, Young Adult, Family Health, Internet statistics & numerical data, Medical History Taking statistics & numerical data, Medical Records Systems, Computerized instrumentation
- Abstract
A detailed family health history is currently the most potentially useful tool for diagnosis and risk assessment in clinical genetics. We developed and evaluated the usability and analytic validity of a patient-driven web-based family health history collection and analysis tool. Health Heritage(©) guides users through the collection of their family health history by relative, generates a pedigree, completes risk assessment, stratification, and recommendations for 89 conditions. We compared the performance of Health Heritage to that of Usual Care using a nonrandomized cohort trial of 109 volunteers. We contrasted the completeness and sensitivity of family health history collection and risk assessments derived from Health Heritage and Usual Care to those obtained by genetic counselors and genetic assessment teams. Nearly half (42%) of the Health Heritage participants reported discovery of health risks; 63% found the information easy to understand and 56% indicated it would change their health behavior. Health Heritage consistently outperformed Usual Care in the completeness and accuracy of family health history collection, identifying 60% of the elevated risk conditions specified by the genetic team versus 24% identified by Usual Care. Health Heritage also had greater sensitivity than Usual Care when comparing the identification of risks. These results suggest a strong role for automated family health history collection and risk assessment and underscore the potential of these data to serve as the foundation for comprehensive, cost-effective personalized genomic medicine., (Copyright © 2010 S. Karger AG, Basel.)
- Published
- 2010
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34. Extracellular potassium dependence of the Na+-K+-ATPase in cardiac myocytes: isoform specificity and effect of phospholemman.
- Author
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Han F, Tucker AL, Lingrel JB, Despa S, and Bers DM
- Subjects
- Animals, Gene Expression Regulation physiology, Isoenzymes, Membrane Proteins genetics, Mice, Mice, Knockout, Phosphoproteins genetics, Phosphorylation, Protein Binding, Sodium, Membrane Proteins metabolism, Myocytes, Cardiac enzymology, Phosphoproteins metabolism, Potassium metabolism, Sodium-Potassium-Exchanging ATPase metabolism
- Abstract
Cardiac Na(+)-K(+)-ATPase (NKA) regulates intracellular Na(+), which in turn affects intracellular Ca(2+) and contractility via the Na(+)/Ca(2+) exchanger. Extracellular K(+) concentration ([K(+)]) is a central regulator of NKA activity. Phospholemman (PLM) has recently been recognized as a critical regulator of NKA in the heart. PLM reduces the intracellular Na(+) affinity of NKA, an effect relieved by PLM phosphorylation. Here we tested whether the NKA alpha(1)- vs. alpha(2)- isoforms have different external K(+) sensitivity and whether PLM and PKA activation affects the NKA affinity for K(+) in mouse cardiac myocytes. We measured the external [K(+)] dependence of the pump current generated by the ouabain-resistant NKA isoform in myocytes from wild-type (WT) mice (i.e., current due to NKA-alpha(1)) and mice in which the NKA isoforms have swapped ouabain affinities (alpha(1) is ouabain sensitive and alpha(2) is ouabain resistant) to assess current due to NKA-alpha(2). We found that NKA-alpha(1) has a higher affinity for external K(+) than NKA-alpha(2) [half-maximal pump activation (K(0.5)) = 1.5 +/- 0.1 vs. 2.9 +/- 0.3 mM]. The apparent external K(+) affinity of NKA was significantly lower in myocytes from WT vs. PLM-knockout mice (K(0.5) = 2.0 +/- 0.2 vs. 1.05 +/- 0.08 mM). However, PKA activation by isoproterenol (1 microM) did not alter the K(0.5) of NKA for external K(+) in WT myocytes. We conclude that 1) NKA-alpha(1) has higher affinity for K(+) than NKA-alpha(2) in cardiac myocytes, 2) PLM decreases the apparent external K(+) affinity of NKA, and 3) phosphorylation of PLM at the cytosolic domain does not alter apparent extracellular K(+) affinity of NKA.
- Published
- 2009
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35. Normal profiles for deciduous dental eruption in domestic piglets: effect of sow, litter, and piglet characteristics.
- Author
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Tucker AL and Widowski TM
- Subjects
- Animals, Female, Male, Swine growth & development, Tooth Eruption physiology
- Abstract
The deciduous dentition of the domestic pig is comprised of 28 teeth (2 x incisors 3/3, canine 1/1, premolars 3/3, molars 0/0). The timing and sequence of deciduous dental eruption were determined from oral exams on 233 Yorkshire piglets from 0 to 5 wk of age. Eruption occurred sooner in gilts for all molariform premolars (p(3), p(4), and p(4), P < 0.01) and first incisor, i(1) (P = 0.004). Birth weight influenced eruption for all teeth except i(1) (i(1), p(3), p(3), p(4), and p(4); P < 0.01), with heavier piglets having earlier eruption. Average daily gain in wk 1 of life was associated with earlier eruption times of p(3) (P = 0.006), p(4) (P = 0.001), and i(1) (P = 0.001), whereas ADG during wk 2 was associated with earlier eruption for p(4) (P = 0.036). The parity (P = 0.025) and age (P = 0.013) of the sow were associated with earlier eruption of i(1). No litter characteristics were found to be significant. Sequence of eruption was determined to be i(1), p(3), p(4), i(1), p(3), p(4), although polymorphisms (reversals) were found to occur in over 40% of individuals of both sexes for mandibular i(1) and p(4) and maxillary p(3) and i(1). Size of the left i(3), which is already erupted at birth as part of the needle teeth dentition, was found to be larger in males (P = 0.026). Body weight gain was not associated with the size of i(3). Eruption times of p(3) and p(4) (the first premolars to erupt) occurred later than previously reported in the literature. Because these teeth are associated with initiation of feeding behavior for miniature breeds, implications of molar eruption on feeding behavior and feed intake should be considered.
- Published
- 2009
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36. Front-line staff perspectives on opportunities for improving the safety and efficiency of hospital work systems.
- Author
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Tucker AL, Singer SJ, Hayes JE, and Falwell A
- Subjects
- Health Priorities, Health Services Research, Hospital Administrators psychology, Hospital Design and Construction, Humans, Interdisciplinary Communication, Materials Management, Hospital, Personnel, Hospital psychology, Program Evaluation, Sampling Studies, United States, Attitude of Health Personnel, Efficiency, Organizational, Hospital Administration standards, Operations Research, Patient Care standards, Quality Assurance, Health Care, Safety Management
- Abstract
Objective: To contrast the safety-related concerns raised by front-line staff about hospital work systems (operational failures) with national patient safety initiatives., Data Sources: Primary data included 1,732 staff-identified operational failures at 20 U.S. hospitals from 2004 to 2006., Study Design: Senior managers observed front-line staff and facilitated open discussion meetings with employees about their patient safety concerns., Data Collection: Hospitals submitted data on the operational failures identified through managers' interactions with front-line workers. Data were analyzed for type of failure and frequency of occurrence. Recommendations from staff were compared with recommendations from national initiatives., Principal Findings: The two most frequent categories of operational failures, equipment/supplies and facility issues, posed safety risks and diminished staff efficiency, but have not been priorities in national initiatives., Conclusions: Our study suggests an underutilized strategy for improving patient safety and staff efficiency: leveraging front-line staff experiences with work systems to identify and address operational failures. In contrast to the perceived tradeoff between safety and efficiency, fixing operational failures can yield benefits for both. Thus, prioritizing improvement of work systems in general, rather than focusing more narrowly on specific clinical conditions, can increase safety and efficiency of hospitals.
- Published
- 2008
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37. Regulation of cardiac myocyte contractility by phospholemman: Na+/Ca2+ exchange versus Na+ -K+ -ATPase.
- Author
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Song J, Zhang XQ, Wang J, Cheskis E, Chan TO, Feldman AM, Tucker AL, and Cheung JY
- Subjects
- Adenoviridae genetics, Animals, Calcium metabolism, Calcium-Binding Proteins deficiency, Calcium-Binding Proteins genetics, Cells, Cultured, Dogs, Electric Capacitance, Genetic Vectors, Homeostasis, Humans, Membrane Potentials, Mice, Mice, Inbred C57BL, Mice, Knockout, Mutation, Signal Transduction, Time Factors, Transduction, Genetic, Calcium-Binding Proteins metabolism, Myocardial Contraction, Myocytes, Cardiac enzymology, Sodium-Calcium Exchanger metabolism, Sodium-Potassium-Exchanging ATPase metabolism
- Abstract
Phospholemman (PLM) regulates cardiac Na(+)/Ca(2+) exchanger (NCX1) and Na(+)-K(+)-ATPase in cardiac myocytes. PLM, when phosphorylated at Ser(68), disinhibits Na(+)-K(+)-ATPase but inhibits NCX1. PLM regulates cardiac contractility by modulating Na(+)-K(+)-ATPase and/or NCX1. In this study, we first demonstrated that adult mouse cardiac myocytes cultured for 48 h had normal surface membrane areas, t-tubules, and NCX1 and sarco(endo)plasmic reticulum Ca(2+)-ATPase levels, and retained near normal contractility, but alpha(1)-subunit of Na(+)-K(+)-ATPase was slightly decreased. Differences in contractility between myocytes isolated from wild-type (WT) and PLM knockout (KO) hearts were preserved after 48 h of culture. Infection with adenovirus expressing green fluorescent protein (GFP) did not affect contractility at 48 h. When WT PLM was overexpressed in PLM KO myocytes, contractility and cytosolic Ca(2+) concentration ([Ca(2+)](i)) transients reverted back to those observed in cultured WT myocytes. Both Na(+)-K(+)-ATPase current (I(pump)) and Na(+)/Ca(2+) exchange current (I(NaCa)) in PLM KO myocytes rescued with WT PLM were depressed compared with PLM KO myocytes. Overexpressing the PLMS68E mutant (phosphomimetic) in PLM KO myocytes resulted in the suppression of I(NaCa) but had no effect on I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the PLMS68E mutant were depressed compared with PLM KO myocytes overexpressing GFP. Overexpressing the PLMS68A mutant (mimicking unphosphorylated PLM) in PLM KO myocytes had no effect on I(NaCa) but decreased I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the S68A mutant were similar to PLM KO myocytes overexpressing GFP. We conclude that at the single-myocyte level, PLM affects cardiac contractility and [Ca(2+)](i) homeostasis primarily by its direct inhibitory effects on Na(+)/Ca(2+) exchange.
- Published
- 2008
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38. Characterization of the phospholemman knockout mouse heart: depressed left ventricular function with increased Na-K-ATPase activity.
- Author
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Bell JR, Kennington E, Fuller W, Dighe K, Donoghue P, Clark JE, Jia LG, Tucker AL, Moorman JR, Marber MS, Eaton P, Dunn MJ, and Shattock MJ
- Subjects
- Action Potentials physiology, Animals, Blood Pressure physiology, Calcium pharmacology, Electrophoresis, Gel, Two-Dimensional, Heart Conduction System physiology, In Vitro Techniques, Membrane Proteins genetics, Mice, Mice, Inbred C57BL, Mice, Knockout, Organ Size physiology, Phenotype, Phosphoproteins genetics, Ventricular Function, Left physiology, Heart physiology, Membrane Proteins physiology, Myocardium enzymology, Phosphoproteins physiology, Sodium-Potassium-Exchanging ATPase metabolism
- Abstract
Phospholemman (PLM, FXYD1), abundantly expressed in the heart, is the primary cardiac sarcolemmal substrate for PKA and PKC. Evidence supports the hypothesis that PLM is part of the cardiac Na-K pump complex and provides the link between kinase activity and pump modulation. PLM has also been proposed to modulate Na/Ca exchanger activity and may be involved in cell volume regulation. This study characterized the phenotype of the PLM knockout (KO) mouse heart to further our understanding of PLM function in the heart. PLM KO mice were bred on a congenic C57/BL6 background. In vivo conductance catheter measurements exhibited a mildly depressed cardiac contractile function in PLM KO mice, which was exacerbated when hearts were isolated and Langendorff perfused. There were no significant differences in action potential morphology in paced Langendorff-perfused hearts. Depressed contractile function was associated with a mild cardiac hypertrophy in PLM KO mice. Biochemical analysis of crude ventricular homogenates showed a significant increase in Na-K-ATPase activity in PLM KO hearts compared with wild-type controls. SDS-PAGE and Western blot analysis of ventricular homogenates revealed small, nonsignificant changes in Na- K-ATPase subunit expression, with two-dimensional gel (isoelectric focusing, SDS-PAGE) analysis revealing minimal changes in ventricular protein expression, indicating that deletion of PLM was the primary reason for the observed PLM KO phenotype. These studies demonstrate that PLM plays an important role in the contractile function of the normoxic mouse heart. Data are consistent with the hypothesis that PLM modulates Na-K-ATPase activity, indirectly affecting intracellular Ca and hence contractile function.
- Published
- 2008
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39. Task force 9: training in the care of adult patients with congenital heart disease.
- Author
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Child JS, Freed MD, Mavroudis C, Moodie DS, and Tucker AL
- Subjects
- Adult, Clinical Competence, Humans, Cardiology education, Curriculum standards, Education, Medical, Graduate standards, Heart Defects, Congenital therapy
- Published
- 2008
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40. RNA toxicity in myotonic muscular dystrophy induces NKX2-5 expression.
- Author
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Yadava RS, Frenzel-McCardell CD, Yu Q, Srinivasan V, Tucker AL, Puymirat J, Thornton CA, Prall OW, Harvey RP, and Mahadevan MS
- Subjects
- Animals, Connexin 43 metabolism, Connexins metabolism, Homeobox Protein Nkx-2.5, Humans, Mice, Mice, Transgenic, Myotonin-Protein Kinase, Protein Serine-Threonine Kinases genetics, RNA, Messenger toxicity, Gap Junction alpha-5 Protein, Homeodomain Proteins genetics, Myotonic Dystrophy genetics, Myotonic Dystrophy metabolism, Protein Serine-Threonine Kinases toxicity, Transcription Factors genetics
- Abstract
Myotonic muscular dystrophy (DM1) is the most common inherited neuromuscular disorder in adults and is considered the first example of a disease caused by RNA toxicity. Using a reversible transgenic mouse model of RNA toxicity in DM1, we provide evidence that DM1 is associated with induced NKX2-5 expression. Transgene expression resulted in cardiac conduction defects, increased expression of the cardiac-specific transcription factor NKX2-5 and profound disturbances in connexin 40 and connexin 43. Notably, overexpression of the DMPK 3' UTR mRNA in mouse skeletal muscle also induced transcriptional activation of Nkx2-5 and its targets. In human muscles, these changes were specific to DM1 and were not present in other muscular dystrophies. The effects on NKX2-5 and its downstream targets were reversed by silencing toxic RNA expression. Furthermore, using Nkx2-5+/- mice, we show that NKX2-5 is the first genetic modifier of DM1-associated RNA toxicity in the heart.
- Published
- 2008
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41. Lysophosphatidic acid (LPA) and angiogenesis.
- Author
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Rivera-Lopez CM, Tucker AL, and Lynch KR
- Subjects
- Amino Acid Sequence, Angiogenesis Inhibitors pharmacology, Animals, Chick Embryo, Drug Evaluation, Preclinical, Molecular Sequence Data, Organophosphates pharmacology, Pyridines pharmacology, Receptors, Lysophosphatidic Acid antagonists & inhibitors, Sequence Homology, Amino Acid, Sphingosine analogs & derivatives, Sphingosine pharmacology, Substrate Specificity, Vascular Endothelial Growth Factor A pharmacology, Lysophospholipids pharmacology, Neovascularization, Physiologic drug effects, Receptors, Lysophosphatidic Acid physiology
- Abstract
Lysophosphatidic acid (LPA) is a simple lipid with many important biological functions such as the regulation of cellular proliferation, cellular migration, differentiation, and suppression of apoptosis. Although a direct angiogenic effect of LPA has not been reported to date, there are indications that LPA promotes angiogenesis. In addition, LPA is a chemoattractant for cultured endothelial cells and promotes barrier function in such cultures. To test the hypothesis that LPA is angiogenic, we used the chicken chorio-allantoic membrane (CAM) assay. Sequence analysis of the cloned, full-length chicken LPA receptor cDNAs revealed three receptor types that are orthologous to the mammalian LPA(1), LPA(2), and LPA(3) receptors. We document herein that LPA is angiogenic in the CAM system and further that synthetic LPA receptor agonists and antagonists mimic or block this response, respectively. Our results predict that LPA receptor antagonists are a possible therapeutic route to interdicting angiogenesis.
- Published
- 2008
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42. Flow cytometry for the rapid detection of bacteria in cell culture production medium.
- Author
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McHugh IO and Tucker AL
- Subjects
- Bacteria isolation & purification, Bacteriological Techniques, Benzothiazoles, Biotechnology methods, Colony Count, Microbial, Predictive Value of Tests, Quinolines, Sensitivity and Specificity, Bacteria growth & development, Culture Media, Flow Cytometry methods
- Abstract
The rapid and sensitive detection of microbial contaminants is critical for timely contamination investigations and monitoring of process control for in vitro protein production systems. A flow cytometric method was developed to monitor two types of cell culture media used in large scale protein production. The process used a DNA dye, thiazole orange, which binds to nucleic acids of viable and nonviable organisms. To ensure a representative sample was tested and to enhance the detection limit, a concentration step before staining and analysis included a double centrifugation. In addition, a washing step was included to eliminate background fluorescence caused by material in the media formulations. The staining and analysis of concentrated and washed samples takes approximately 0.5 h and provides objective results. The feasibility of the method was demonstrated by spiking sterile media with six bacterial species that represent the most commonly encountered bacterial contaminants. In addition to the bacterial spiking study, 164 lots of large scale production medium were tested by the flow cytometric method in parallel with conventional culture using Trypticase Soy Broth (TSB). In the bacterial spiking study, the concentration method increased the microbial titer by 2 logs. The detection limit of organisms within the medium was determined to be 1 CFU/ml. There was 100% correlation between the flow cytometric method and the standard aerobic plate count method using Trypticase Soy Agar. In the parallel study on 164 lots of large scale production media, the flow cytometric method was compared against culture in TSB. The sensitivity of the method was determined to be 100%, the specificity was 99.4%, the positive predictive value was 83%, and the negative predictive value was 100%. To reduce reporting of false positives, an initial positive result should be confirmed by an additional sample. The analytic sensitivity, specificity, and objectivity of this flow cytometric method indicate this method is valuable in the monitoring of production media for microbial contamination., ((c) 2007 International Society for Analytical Cytology)
- Published
- 2007
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43. A1 adenosine receptor activation promotes angiogenesis and release of VEGF from monocytes.
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Clark AN, Youkey R, Liu X, Jia L, Blatt R, Day YJ, Sullivan GW, Linden J, and Tucker AL
- Subjects
- Adenosine analogs & derivatives, Adenosine pharmacology, Adenosine A1 Receptor Agonists, Animals, Aorta, Chick Embryo, Humans, Rats, Receptor, Adenosine A1 metabolism, Receptor, Adenosine A3 metabolism, Receptor, Adenosine A3 physiology, Receptors, Adenosine A2 metabolism, Receptors, Adenosine A2 physiology, Monocytes metabolism, Neovascularization, Physiologic, Receptor, Adenosine A1 physiology, Vascular Endothelial Growth Factor A metabolism
- Abstract
Adenosine is a proangiogenic purine nucleoside released from ischemic and hypoxic tissues. Of the 4 adenosine receptor (AR) subtypes (A1, A2A, A2B, and A3), the A2 and A3 have been previously linked to the modulation of angiogenesis. We used the chicken chorioallantoic membrane (CAM) model to determine whether A1 AR activation affects angiogenesis. We cloned and pharmacologically characterized chicken AR subtypes to evaluate the selectivity of various agonists and antagonists. Application of the A1 AR-selective agonist N6-cyclopentyladenosine (CPA; 100 nmol/L) to the CAM resulted in a 40% increase in blood vessel number (P<0.01), which was blocked by the A1 AR-selective antagonist C8-(N-methylisopropyl)-amino-N6-(5'-endohydroxy)-endonorbornan-2-yl-9-methyladenine (WRC-0571; 1 micromol/L). Selective A2A AR agonists did not stimulate angiogenesis in the CAM. In an ex vivo rat aortic ring model of angiogenesis that includes cocultured endothelial cells, fibroblasts, and smooth muscle cells, 50 nmol/L CPA did not directly stimulate capillary formation; however, medium from human mononuclear cells pretreated with CPA, but not vehicle, increased capillary formation by 48% (P<0.05). This effect was blocked by WRC-0571 (1.5 micromol/L) or anti-VEGF antibody (1 microg/mL). CPA (5 nmol/L) stimulated a 1.7-fold increase in VEGF release from the mononuclear cells. This is the first study to show that A1 AR activation induces angiogenesis. Stimulation of A2 ARs on endothelial cells results in proliferation and tube formation, and A2 and A3 ARs on inflammatory cells modulate release of angiogenic factors. We conclude that adenosine promotes a coordinated angiogenic response through its interactions with multiple receptors on multiple cell types.
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- 2007
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44. Regulation of cardiac Na+/Ca2+ exchanger by phospholemman.
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Cheung JY, Rothblum LI, Moorman JR, Tucker AL, Song J, Ahlers BA, Carl LL, Wang J, and Zhang XQ
- Subjects
- Animals, Calcium metabolism, Cell Line, Homeostasis, Humans, Immunoprecipitation, Sodium-Potassium-Exchanging ATPase metabolism, Calcium-Binding Proteins physiology, Myocardium metabolism, Sodium-Calcium Exchanger physiology
- Abstract
Phospholemman (PLM) is the first sequenced member of the FXYD family of regulators of ion transport. The mature protein has 72 amino acids and consists of an extracellular N terminus containing the signature FXYD motif, a single transmembrane (TM) domain, and a cytoplasmic C-terminal domain containing four potential sites for phosphorylation. PLM and other members of the FXYD family are known to regulate Na+-K+-ATPase. Using adenovirus-mediated gene transfer into adult rat cardiac myocytes, we showed that changes in contractility and intracellular Ca2+ homeostasis associated with PLM overexpression or downregulation are not consistent with the effects expected from inhibition of Na+-K+-ATPase by PLM. Additional studies with heterologous expression of PLM and cardiac Na+/Ca2+ exchanger 1 (NCX1) in HEK293 cells and cardiac myocytes isolated from PLM-deficient mice demonstrated by co-localization, co-immunoprecipitation, and electrophysiological and radioactive tracer uptake techniques that PLM associates with NCX1 in the sarcolemma and transverse tubules and that PLM inhibits NCX1, independent of its effects on Na+-K+-ATPase. Mutational analysis indicates that the cytoplasmic domain of PLM is required for its regulation of NCX1. In addition, experiments using phosphomimetic and phospho-deficient PLM mutants, as well as activators of protein kinases A and C, indicate that PLM phosphorylated at serine68 is the active form that inhibits NCX1. This is in sharp contrast to the finding that the unphosphorylated PLM form inhibits Na+-K+-ATPase. We conclude that PLM regulates cardiac contractility by modulating the activities of NCX and Na+-K+-ATPase.
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- 2007
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45. A mathematical model for the onset of avascular tumor growth in response to the loss of p53 function.
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Levine HA, Smiley MW, Tucker AL, and Nilsen-Hamilton M
- Abstract
We present a mathematical model for the formation of an avascular tumor based on the loss by gene mutation of the tumor suppressor function of p53. The wild type p53 protein regulates apoptosis, cell expression of growth factor and matrix metalloproteinase, which are regulatory functions that many mutant p53 proteins do not possess. The focus is on a description of cell movement as the transport of cell population density rather than as the movement of individual cells. In contrast to earlier works on solid tumor growth, a model is proposed for the initiation of tumor growth. The central idea, taken from the mathematical theory of dynamical systems, is to view the loss of p53 function in a few cells as a small instability in a rest state for an appropriate system of differential equations describing cell movement. This instability is shown (numerically) to lead to a second, spatially inhomogeneous, solution that can be thought of as a solid tumor whose growth is nutrient diffusion limited. In this formulation, one is led to a system of nine partial differential equations. We show computationally that there can be tumor states that coexist with benign states and that are highly unstable in the sense that a slight increase in tumor size results in the tumor occupying the sample region while a slight decrease in tumor size results in its ultimate disappearance.
- Published
- 2007
46. Phospholemman phosphorylation mediates the protein kinase C-dependent effects on Na+/K+ pump function in cardiac myocytes.
- Author
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Han F, Bossuyt J, Despa S, Tucker AL, and Bers DM
- Subjects
- Animals, Biological Transport drug effects, Biological Transport physiology, Carcinogens pharmacology, Cyclic AMP-Dependent Protein Kinases metabolism, Heart Ventricles cytology, Heart Ventricles metabolism, Membrane Proteins genetics, Mice, Mice, Inbred C57BL, Mice, Knockout, Monocytes metabolism, Phorbol 12,13-Dibutyrate pharmacology, Phosphoproteins genetics, Phosphorylation, Serine metabolism, Sodium metabolism, Membrane Proteins metabolism, Myocytes, Cardiac metabolism, Phosphoproteins metabolism, Protein Kinase C metabolism, Sodium-Potassium-Exchanging ATPase metabolism
- Abstract
Because phospholemman (PLM) regulates the Na(+)/K(+) pump (NKA) and is a major cardiac phosphorylation target for both protein kinase A (at Ser68) and protein kinase C (PKC) (at both Ser63 and Ser68), we evaluated whether PLM mediates the PKC-dependent regulation of NKA function and protein kinase A/PKC crosstalk in ventricular myocytes. PKC was activated by PDBu (300 nmol/L), and we measured NKA-mediated [Na(+)](i) decline (fluorescence measurements) and current (I(pump)) (voltage clamp). In wild-type mouse myocytes, PDBu increased PLM phosphorylation at Ser63 and Ser68, I(pump) (both at 10 and 100 mmol/L Na(+) in the pipette solution) and maximal NKA-mediated Na(+) extrusion rate (V(max)) from 7.9+/-1.1 to 12.7+/-1.9 mmol.L(-1) per minute without altering NKA affinity for internal Na(+) (K(0.5)). In PLM knockout mice, PDBu had no effect on either V(max) or K(0.5). After pretreatment with isoproterenol (ISO) (1 mumol/L), PDBu still increased the NKA V(max) and PLM phosphorylation at Ser63 and Ser68. Conversely, after pretreatment with PDBu, ISO further increased the Na(+) affinity of NKA and phosphorylation at Ser68, as it did alone without PDBu. The final NKA activity was independent of the application sequence. The NKA activity in PLM knockout myocytes, after normalizing the protein level, was similar to that after PDBu and ISO treatment. We conclude that (1) PLM mediates the PKC-dependent activation of NKA function in cardiac myocytes, (2) PDBu and ISO effects are additive in the mouse (affecting mainly V(max) and K(0.5), respectively), and (3) PDBu and ISO combine to activate NKA in wild-type to the level found in the PLM knockout mouse.
- Published
- 2006
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47. Altered contractility and [Ca2+]i homeostasis in phospholemman-deficient murine myocytes: role of Na+/Ca2+ exchange.
- Author
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Tucker AL, Song J, Zhang XQ, Wang J, Ahlers BA, Carl LL, Mounsey JP, Moorman JR, Rothblum LI, and Cheung JY
- Subjects
- Action Potentials, Animals, Cell Culture Techniques, Cells, Cultured, Crosses, Genetic, Homeostasis, Membrane Proteins genetics, Mice, Mice, Congenic, Mice, Inbred C57BL, Mice, Knockout, Patch-Clamp Techniques, Phosphoproteins genetics, Calcium metabolism, Membrane Proteins deficiency, Myocardial Contraction physiology, Myocytes, Cardiac physiology, Phosphoproteins deficiency, Sodium-Calcium Exchanger metabolism
- Abstract
Phospholemman (PLM) regulates contractility and Ca(2+) homeostasis in cardiac myocytes. We characterized excitation-contraction coupling in myocytes isolated from PLM-deficient mice backbred to a pure congenic C57BL/6 background. Cell length, cell width, and whole cell capacitance were not different between wild-type and PLM-null myocytes. Compared with wild-type myocytes, Western blots indicated total absence of PLM but no changes in Na(+)/Ca(2+) exchanger, sarcoplasmic reticulum (SR) Ca(2+)-ATPase, alpha(1)-subunit of Na(+)-K(+)-ATPase, and calsequestrin levels in PLM-null myocytes. At 5 mM extracellular Ca(2+) concentration ([Ca(2+)](o)), contraction and cytosolic [Ca(2+)] ([Ca(2+)](i)) transient amplitudes and SR Ca(2+) contents in PLM-null myocytes were significantly (P < 0.0004) higher than wild-type myocytes, whereas the converse was true at 0.6 mM [Ca(2+)](o). This pattern of contractile and [Ca(2+)](i) transient abnormalities in PLM-null myocytes mimics that observed in adult rat myocytes overexpressing the cardiac Na(+)/Ca(2+) exchanger. Indeed, we have previously reported that Na(+)/Ca(2+) exchange currents were higher in PLM-null myocytes. Activation of protein kinase A resulted in increased inotropy such that there were no longer any contractility differences between the stimulated wild-type and PLM-null myocytes. Protein kinase C stimulation resulted in decreased contractility in both wild-type and PLM-null myocytes. Resting membrane potential and action potential amplitudes were similar, but action potential duration was much prolonged (P < 0.04) in PLM-null myocytes. Whole cell Ca(2+) current densities were similar between wild-type and PLM-null myocytes, as were the fast- and slow-inactivation time constants. We conclude that a major function of PLM is regulation of cardiac contractility and Ca(2+) fluxes, likely by modulating Na(+)/Ca(2+) exchange activity.
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- 2006
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48. Operational failures and interruptions in hospital nursing.
- Author
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Tucker AL and Spear SJ
- Subjects
- Cross-Sectional Studies, Health Care Surveys, Humans, Interviews as Topic, United States, Equipment Failure statistics & numerical data, Nursing Informatics organization & administration, Nursing Staff, Hospital
- Abstract
Objective: To describe the work environment of hospital nurses with particular focus on the performance of work systems supplying information, materials, and equipment for patient care., Data Sources: Primary observation, semistructured interviews, and surveys of hospital nurses., Study Design: We sampled a cross-sectional group of six U.S. hospitals to examine the frequency of work system failures and their impact on nurse productivity., Data Collection: We collected minute-by-minute data on the activities of 11 nurses. In addition, we conducted interviews with six of these nurses using questions related to obstacles to care. Finally, we created and administered two surveys in 48 nursing units, one for nurses and one for managers, asking about the frequency of specific work system failures., Principal Findings: Nurses we observed experienced an average of 8.4 work system failures per 8-hour shift. The five most frequent types of failures, accounting for 6.4 of these obstacles, involved medications, orders, supplies, staffing, and equipment. Survey questions asking nurses how frequently they experienced these five categories of obstacles yielded similar frequencies. For an average 8-hour shift, the average task time was only 3.1 minutes, and in spite of this, nurses were interrupted mid-task an average of eight times per shift., Conclusions: Our findings suggest that nurse effectiveness can be increased by creating improvement processes triggered by the occurrence of work system failures, with the goal of reducing future occurrences. Second, given that nursing work is fragmented and unpredictable, designing processes that are robust to interruption can help prevent errors.
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- 2006
- Full Text
- View/download PDF
49. The allosteric enhancer PD81,723 increases chimaeric A1/A2A adenosine receptor coupling with Gs.
- Author
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Bhattacharya S, Youkey RL, Ghartey K, Leonard M, Linden J, and Tucker AL
- Subjects
- Adenosine analogs & derivatives, Adenosine pharmacology, Adrenergic alpha-Agonists pharmacology, Adrenergic alpha-Antagonists pharmacology, Animals, Cell Line, Cyclic AMP metabolism, Dogs, Humans, Iodobenzenes pharmacology, Kidney cytology, Protein Conformation, Protein Interaction Mapping, Protein Structure, Tertiary, Radioligand Assay, Receptor, Adenosine A1 chemistry, Receptor, Adenosine A1 genetics, Receptor, Adenosine A1 metabolism, Receptor, Adenosine A2A chemistry, Receptor, Adenosine A2A drug effects, Receptor, Adenosine A2A genetics, Recombinant Fusion Proteins chemistry, Recombinant Fusion Proteins metabolism, Transfection, Xanthines pharmacology, Allosteric Regulation drug effects, GTP-Binding Protein alpha Subunits, Gi-Go metabolism, GTP-Binding Protein alpha Subunits, Gs metabolism, Receptor, Adenosine A1 drug effects, Recombinant Fusion Proteins drug effects, Thiophenes pharmacology
- Abstract
PD81,723 {(2-amino-4,5-dimethyl-3-thienyl)-[3-(trifluromethyl)-phenyl]methanone} is a selective allosteric enhancer of the G(i)-coupled A1 AR (adenosine receptor) that is without effect on G(s)-coupled A2A ARs. PD81,723 elicits a decrease in the dissociation kinetics of A1 AR agonist radioligands and an increase in functional agonist potency. In the present study, we sought to determine whether enhancer sensitivity is dependent on coupling domains or G-protein specificity of the A1 AR. Using six chimaeric A1/A2A ARs, we show that the allosteric effect of PD81,723 is maintained in a chimaera in which the predominant G-protein-coupling domain of the A1 receptor, the 3ICL (third intracellular loop), is replaced with A2A sequence. These chimaeric receptors are dually coupled with G(s) and G(i), and PD81,723 increases the potency of N6-cyclopentyladenosine to augment cAMP accumulation with or without pretreatment of cells with pertussis toxin. Thus PD81,723 has similar functional effects on chimaeric receptors with A1 transmembrane sequences that couple with G(i) or G(s). This is the first demonstration that an allosteric regulator can function in the context of a switch in G-protein-coupling specificity. There is no enhancement by PD81,723 of G(i)-coupled A2A chimaeric receptors with A1 sequence replacing A2A sequence in the 3ICL. The results suggest that the recognition site for PD81,723 is on the A1 receptor and that the enhancer acts to directly stabilize the receptor to a conformational state capable of coupling with G(i) or G(s).
- Published
- 2006
- Full Text
- View/download PDF
50. Phospholemman inhibition of the cardiac Na+/Ca2+ exchanger. Role of phosphorylation.
- Author
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Zhang XQ, Ahlers BA, Tucker AL, Song J, Wang J, Moorman JR, Mounsey JP, Carl LL, Rothblum LI, and Cheung JY
- Subjects
- Adenosine Triphosphatases chemistry, Alanine chemistry, Animals, Calsequestrin chemistry, Cell Line, Cloning, Molecular, Colforsin chemistry, Colforsin pharmacology, Cyclic AMP-Dependent Protein Kinases metabolism, Glutamic Acid chemistry, Humans, Immunoblotting, Ions, Membrane Proteins metabolism, Mice, Mice, Knockout, Muscle Cells metabolism, Muscles metabolism, Mutation, Myocardium metabolism, Phosphoproteins metabolism, Phosphorylation, Serine chemistry, Sodium chemistry, Sodium-Calcium Exchanger genetics, Sodium-Calcium Exchanger physiology, Tetradecanoylphorbol Acetate chemistry, Transfection, Membrane Proteins physiology, Phosphoproteins physiology, Sodium-Calcium Exchanger chemistry
- Abstract
We have demonstrated previously that phospholemman (PLM), a 15-kDa integral sarcolemmal phosphoprotein, inhibits the cardiac Na+/Ca2+ exchanger (NCX1). In addition, protein kinase A phosphorylates serine 68, whereas protein kinase C phosphorylates both serine 63 and serine 68 of PLM. Using human embryonic kidney 293 cells that are devoid of both endogenous PLM and NCX1, we first demonstrated that the exogenous NCX1 current (I(NaCa)) was increased by phorbol 12-myristate 13-acetate (PMA) but not by forskolin. When co-expressed with NCX1, PLM resulted in: (i) decreases in I(NaCa), (ii) attenuation of the increase in I(NaCa) by PMA, and (iii) additional reduction in I(NaCa) in cells treated with forskolin. Mutating serine 63 to alanine (S63A) preserved the sensitivity of PLM to forskolin in terms of suppression of I(NaCa), whereas mutating serine 68 to alanine (S68A) abolished the inhibitory effect of PLM on I(NaCa). Mutating serine 68 to glutamic acid (phosphomimetic) resulted in additional suppression of I(NaCa) as compared with wild-type PLM. These results suggest that PLM phosphorylated at serine 68 inhibited I(NaCa). The physiological significance of inhibition of NCX1 by phosphorylated PLM was evaluated in PLM-knock-out (KO) mice. When compared with wild-type myocytes, I(NaCa) was significant larger in PLM-KO myocytes. In addition, the PMA-induced increase in I(NaCa) was significantly higher in PLM-KO myocytes. By contrast, forskolin had no effect on I(NaCa) in wild-type myocytes. We conclude that PLM, when phosphorylated at serine 68, inhibits Na+/Ca2+ exchange in the heart.
- Published
- 2006
- Full Text
- View/download PDF
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