bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changing Team Practice: Applying Evidence‐Based Brain Injury Guidelines to Clinical Practice
Authors: Bader Mary Kay 
Published: December 2004

ABSTRACT Background: Trauma teams strive to provide care based on best practice. Examining the outcomes of patients sustaining severe traumatic brain injury (TBI) at our trauma center from 1994–1997, we discovered that at 6 months, 43% of the patients had expired and 30% sustained severe disability. The outcomes were consistent with some studies published on TBI in the 1980s and early 1990s. Research in the past decade on resuscitation efforts and new technology for monitoring the effects of secondary brain injury has produced improved outcomes in managing these patients. In 1995, evidence‐based clinical guidelines for treating severe TBI were published recommending changes in the care of these patients. The guidelines challenged hospitals to evaluate their care practices and examine the clinical outcomes of this high‐risk group. Approach: Motivated by the new practice recommendations and the potential for impacting patient outcomes, the neuro clinical nurse specialist (CNS) formed a multidisciplinary team to begin the process of performance improvement. Patient management practices were examined and relevant research evaluated. The team melded the national guidelines and supporting literature into hospital‐based clinical guidelines with a series of care algorithms directing the care of these patients from admission, through the operative period, to the intensive care (ICU) phase. Prospective data were collected, and care patterns were analyzed on an annual basis. The team reconvened as needed every 12 to 18 months to discuss issues, review new literature, and alter the clinical guidelines. A vital issue emerged in 2000, which was brought to the neuro CNS by several families. Although liberal family presence was supported in the ICU, this practice was not present on the floor or rehab areas. A team of practitioners and former patients   and families collaborated in August of 2000 exploring the patient‐family experiences during the hospitalization. Supporting evidence‐based nursing literature was reviewed, which led to the adoption of family‐centered care throughout patients' hospitalization. Findings: Seven years after integrating these changes, the 6‐month outcomes have improved dramatically: 72.1% showed good outcome/moderate disability, 13.6% showed severe disability to persistent vegetative state, and 14.3% died. In addition, families have become a vital force in our team's care. With key hospital team members, the families have developed a TBI family manual and formed a “call‐back program” to provide support to new TBI families. The TBI families have donated more than $3 million in gifts/money to support the program. Discussion: This presentation will utilize a performance improvement approach revealing the actions used by the team to apply evidence‐based guidelines and literature to the clinical setting. Statistical analysis using an ordinal regression model will provide outcome data emphasizing the positive aspects of applying evidence‐based guidelines/literature to practice.
Learning from Experience: U.K. Perspectives on Translation Research
Authors: Rycroft‐Malone Joanne 
Published: December 2004

ABSTRACT Objective: Evidence‐based practice has emerged as the dominant theme of practice, policy, management, and education within the United Kingdom's National Health Service (NHS). Policy frameworks typically indicate that the implementation of evidence into practice follows a logical and rational model from production, to dissemination, and then implementation, audit, and improvement. However, examples and experience from practice suggest that getting evidence into practice is a messy and complex process, which cannot be explained by simplistic processes. This paper will outline some examples from U.K.‐based translation research and consider the implications they have for the advancement of translation science. Approach: Findings from U.K. projects such as the Promoting Action on Clinical Effectiveness (PACE) programme (Dopson et al. 1999) and the South Thames Evidence‐Based Practice Project (STEP; Redfern et al. 2000) have been reviewed. From this analysis, a number of main themes emerge as influential in the uptake of evidence into practice. Findings: Key findings include: “Evidence” is socially and historically constructed, change does not follow a prescribed or logical path, context can be a potent mediator, and individuals and groups have significant roles to play in both facilitating and inhibiting implementation efforts. Conclusions: Based on these findings, a number of suggestions can be made for translation science: (1) There is a need to particularise and situate evidence, (2) improving practice is likely to mean drawing on different forms of information and knowledge to ascertain evidence of what works, (3) approaches and interventions that work with and develop the context may be more successful than those that ignore it, and (4) there is a need to pay more attention to the social and human aspects of getting evidence into practice. Implications: The implications these conclusions have for research and practice will be considered as part of this presentation.
Translating Research into Practice: A United States Perspective
Authors: Titler Marita 
Published: December 2004

ABSTRACT Objective: This paper overviews the state of the science of translation research in the United States, using examples to illustrate major findings. Design/Methods: A variety of electronic and manual search strategies were used to access studies, including studies funded by federal agencies. Translating research into practice (TRIP) studies were reviewed, critiqued, and synthesized to summarize research methods and findings. Variables: Study purpose, methods, TRIP interventions tested, adherence to evidence‐based practices (EBPs), and effect on patient outcomes were compared across TRIP studies. Findings from each study were summarized. Findings: Most studies focused on clinical versus organizational EBPs. Descriptive, cross‐sectional, and experimental methods have been employed. Lack of comparison groups in some studies poses threats to internal validity. A variety of single and multifaceted TRIP interventions have been tested. Both qualitative and quantitative methods have been used. Improved patient outcomes and adherence to EBPs are demonstrated when multifaceted TRIP interventions are employed. TRIP science has evolved from demonstration projects to TRIP intervention testing. Few studies have used randomized clinical trials to test TRIP interventions. Several methodological challenges (e.g., methods of measuring adherence, organization context) remain in TRIP science. Conclusions/Implications: More experimental designs are needed to test TRIP interventions, and more studies on organizational variables are necessary. Methods for measuring TRIP intervention “dose” are lacking. Factors that impact use of EBPs include complexity of the EBP topic, organizational context, single versus multifaceted TRIP interventions, methods of communicating the EBPs to health care providers, and integration of the evidence into organizational structures and processes (e.g., documentation systems). Given the state of the science in the United States, priority should be on conducting experimental studies to test the effectiveness of TRIP interventions and on gaining a better understanding about which TRIP interventions work in which context and with what types of clinical and administrative topics.
Antigua revisited: the impact of climate change on sand and nest temperatures at a hawksbill turtle (Eretmochelys imbricata) nesting beach
Authors: Glen F. , Mrosovsky N. 
Published: December 2004

AbstractWhether a turtle embryo develops into a male or a female depends, as with many other reptiles, on the temperature during incubation of the eggs. With sea turtles, warm temperatures produce 100% females. Therefore, global warming has the potential to drastically alter their sex ratios. Air temperatures on Antigua have increased by 0.7°C over the last 35 years. Measurements in both the sand and the clutches laid by hawksbill turtles (Eretmochelys imbricata) at Pasture Bay, Antigua, show that for important parts of the nesting season temperatures are already above the level producing 50% of each sex (pivotal level). Comparisons are made to sand temperature measurements taken on this beach in 1989 and 1990. It is estimated that fewer males were produced in 2003 than in the previous years. Recommendations are made for close monitoring of the fertility of eggs and for research on any turtles nesting at cooler times of year.
Role of anosXHomolog inStreptococcus gordoniiin Aerobic Growth and Biofilm Formation
Authors: Loo C. Y. , Mitrakul K. , Jaafar S. , Gyurko C. , Hughes C. V. , Ganeshkumar N. 
Published: December 2004

ABSTRACTOral streptococci such asStreptococcus gordoniiare facultative anaerobes that initiate biofilm formation on tooth surfaces. An isolatedS. gordonii::Tn917-lacbiofilm-defective mutant contained a transposon insertion in an open reading frame (ORF) encoding a homolog of NosX ofRalstonia eutropha, a putative maturation factor of nitrous oxide reductase. Located downstream are two genes,qor1andqor2, predicted to encode two putative NADPH quinone oxidoreductases. These three genes are cotranscribed, forming a putative oxidative stress response (osr) operon inS. gordonii. Inactivation ofnosX,qor1, orqor2resulted in biofilm-defective phenotypes. Expression ofnosX, measured by the β-galactosidase activity of thenosX::Tn917-lacmutant, was growth-phase dependent and enhanced when grown under aerobic conditions or in the presence of paraquat. Real-time reverse transcription-PCR revealed thatnosX-specific mRNA levels were increased approximately 8.4 and 3.5 fold in biofilm-derived cells grown on plastic and glass, respectively, when compared to planktonic cells. Expression ofnosXincreased 19.9 fold in cells grown under aerated aerobic conditions and 4.7 fold in cells grown under static aerobic conditions. Two ORFs immediately adjacent to theosroperon encode a putative NADH oxidase (Nox) and a putative thiol-specific antioxidant enzyme (AhpC, for alkyl hydroperoxide peroxidase C). Expression ofnoxandahpCwas also significantly increased in cells grown under aerated and static aerobic conditions when compared to anaerobic conditions. In addition,noxexpression was increased in biofilm cells compared to planktonic cells. These genes may be part of an island that deals with oxidoreductive response, some of which may be important inS. gordoniibiofilm formation.
Role and Regulation of σ
s
in General Resistance Conferred by Low-Shear Simulated Microgravity in
Escherichia coli
Authors: Lynch S. V. , Brodie E. L. , Matin A. 
Published: December 2004

ABSTRACT

Life on Earth evolved in the presence of gravity, and thus it is of interest from the perspective of space exploration to determine if diminished gravity affects biological processes. Cultivation of
Escherichia coli
under low-shear simulated microgravity (SMG) conditions resulted in enhanced stress resistance in both exponential- and stationary-phase cells, making the latter superresistant. Given that microgravity of space and SMG also compromise human immune response, this phenomenon constitutes a potential threat to astronauts. As low-shear environments are encountered by pathogens on Earth as well, SMG-conferred resistance is also relevant to controlling infectious disease on this planet. The SMG effect resembles the general stress response on Earth, which makes bacteria resistant to multiple stresses; this response is σ
s
dependent, irrespective of the growth phase. However, SMG-induced increased resistance was dependent on σ
s
only in stationary phase, being independent of this sigma factor in exponential phase. σ
s
concentration was some 30% lower in exponential-phase SMG cells than in normal gravity cells but was twofold higher in stationary-phase SMG cells. While SMG affected σ
s
synthesis at all levels of control, the main reasons for the differential effect of this gravity condition on σ
s
levels were that it rendered the sigma protein less stable in exponential phase and increased
rpoS
mRNA translational efficiency. Since σ
s
regulatory processes are influenced by mRNA and protein-folding patterns, the data suggest that SMG may affect these configurations.
MazF-Mediated Cell Death in
Escherichia coli
: a Point of No Return
Authors: Amitai Shahar , Yassin Yussuf , Engelberg-Kulka Hanna 
Published: December 2004

ABSTRACT

mazEF
is a stress-induced toxin-antitoxin module, located on the chromosome of
Escherichia coli
, that we have previously described to be responsible for programmed cell death in
E. coli. mazF
specifies a stable toxin, and
mazE
specifies a labile antitoxin. Recently, it was reported that inhibition of translation and cell growth by ectopic overexpression of the toxin MazF can be reversed by the action of the antitoxin MazE ectopically overexpressed at a later time. Based on these results, it was suggested that rather than inducing cell death,
mazF
induces a state of reversible bacteriostasis (K. Pederson, S. K. Christensen, and K. Gerdes, Mol. Microbiol. 45:501-510, 2002). Using a similar ectopic overexpression system, we show here that overexpression of MazE could reverse MazF lethality only over a short window of time. The size of that window depended on the nature of the medium in which MazF was overexpressed. Thus, we found “a point of no return,” which occurred sooner in minimal M9 medium than it did in the rich Luria-Bertani medium. We also describe a state in which the effect of MazF on translation could be separated from its effect on cell death: MazE overproduction could completely reverse the inhibitory effect of MazF on translation, while not affecting the bacteriocidic effect of MazF at all. Our results reported here support our view that the
mazEF
module mediates cell death and is part of a programmed cell death network.
TcpH Influences Virulence Gene Expression inVibrio choleraeby Inhibiting Degradation of the Transcription Activator TcpP
Authors: Beck Nancy A. , Krukonis Eric S. , DiRita Victor J. 
Published: December 2004

ABSTRACTExpression oftoxT, the transcription activator of cholera toxin and pilus production inVibrio cholerae, is the consequence of a complex cascade of regulatory events that culminates in activation of thetoxTpromoter by TcpP and ToxR, two membrane-localized transcription factors. Both are encoded in operons with genes whose products, TcpH and ToxS, which are also membrane localized, are hypothesized to control their activity. In this study we analyzed the role of TcpH in controlling TcpP function. We show that a mutant ofV. choleraelacking TcpH expressed virtually undetectable levels of TcpP, althoughtcpPmRNA levels remain unaffected. A time course experiment showed that levels of TcpP, expressed from a plasmid, are dramatically reduced over time without co-overexpression of TcpH. By contrast, deletion oftoxSdid not affect ToxR protein levels. A fusion protein in which the TcpP periplasmic domain is replaced with that of ToxR remains stable, suggesting that the periplasmic domain of TcpP is the target for degradation of the protein. Placement of the periplasmic domain of TcpP on ToxR, an otherwise stable protein, results in instability, providing further evidence for the hypothesis that the periplasmic domain of TcpP is a target for degradation. Consistent with this interpretation is our finding that derivatives of TcpP lacking a periplasmic domain are more stable inV. choleraethan are derivatives in which the periplasmic domain has been truncated. This work identifies at least one role for the periplasmic domain of TcpP, i.e., to act as a target for a protein degradation pathway that regulates TcpP levels. It also provides a rationale for why theV. cholerae tcpHmutant strain is avirulent. We hypothesize that regulator degradation may be an important mechanism for regulating virulence gene expression inV. cholerae.
Negative Regulation of DNA Repair Gene (ung) Expression by the CpxR/CpxA Two-Component System inEscherichia coliK-12 and Induction of Mutations by Increased Expression of CpxR
Authors: Ogasawara Hiroshi , Teramoto Jun , Hirao Kiyo , Yamamoto Kaneyoshi , Ishihama Akira , Utsumi Ryutaro 
Published: December 2004

ABSTRACTInEscherichia coliK-12 overexpressing CpxR, transcription of theunggene for uracil-DNA glycosylase was repressed, ultimately leading to the induction of mutation. Gel shift, DNase I footprinting, and in vitro transcription assays all indicated negative regulation ofungtranscription by phosphorylated CpxR. Based on the accumulated results, we conclude thatunggene expression is negatively regulated by the two-component system of CpxR/CpxA signal transduction.
Endopeptidase Penicillin-Binding Proteins 4 and 7 Play Auxiliary Roles in Determining Uniform Morphology ofEscherichia coli
Authors: Meberg Bernadette M. , Paulson Avery L. , Priyadarshini Richa , Young Kevin D. 
Published: December 2004

ABSTRACTThe low-molecular-weight (LMW) penicillin-binding protein, PBP 5, plays a dominant role in determining the uniform cell shape ofEscherichia coli. However, the physiological functions of six other LMW PBPs are unknown, even though the existence and enzymatic activities of four of these were established three decades ago. By applying fluorescence-activated cell sorting (FACS) to quantify the cellular dimensions of multiple PBP mutants, we found that the endopeptidases PBP 4 and PBP 7 also influence cell shape in concert with PBP 5. This is the first reported biological function for these two proteins. In addition, the combined loss of threedd-carboxypeptidases, PBPs 5 and 6 and DacD, also impaired cell shape. In contrast to previous reports based on visual inspection alone, FACS analysis revealed aberrant morphology in a mutant lacking only PBP 5, a phenotype not shared by any other strain lacking a single LMW PBP. PBP 5 removes the terminald-alanine from pentapeptide side chains of muropeptide subunits, and pentapeptides act as donors for cross-linking adjacent side chains. As endopeptidases, PBPs 4 and 7 cleave cross-links in the cell wall. Therefore, overall cell shape may be determined by the existence or location of a specific type of peptide cross-link, with PBP 5 activity influencing how many cross-links are made and PBPs 4 and 7 acting as editing enzymes to remove inappropriate cross-links.
Functional Analysis of the Cell Division Protein FtsW ofEscherichia coli
Authors: Pastoret Soumya , Fraipont Claudine , den Blaauwen Tanneke , Wolf Benoît , Aarsman Mirjam E. G. , Piette André , Thomas Annick , Brasseur Robert , Nguyen-Distèche Martine 
Published: December 2004

ABSTRACTSite-directed mutagenesis experiments combined with fluorescence microscopy shed light on the role ofEscherichia coliFtsW, a membrane protein belonging to the SEDS family that is involved in peptidoglycan assembly during cell elongation, division, and sporulation. This essential cell division protein has 10 transmembrane segments (TMSs). It is a late recruit to the division site and is required for subsequent recruitment of penicillin-binding protein 3 (PBP3) catalyzing peptide cross-linking. The results allow identification of several domains of the protein with distinct functions. The localization of PBP3 to the septum was found to be dependent on the periplasmic loop located between TMSs 9 and 10. The E240-A249 amphiphilic peptide in the periplasmic loop between TMSs 7 and 8 appears to be a key element in the functioning of FtsW in the septal peptidoglycan assembly machineries. The intracellular loop (containing the R166-F178 amphiphilic peptide) between TMSs 4 and 5 and Gly 311 in TMS 8 are important components of the amino acid sequence-folding information.
Characterization of Soluble Enzyme II Complexes of the
Escherichia coli
Phosphotransferase System
Authors: Aboulwafa Mohammad , Saier Milton H. 
Published: December 2004

ABSTRACT

Plasmid-encoded His-tagged glucose permease of
Escherichia coli
, the enzyme IIBC
Glc
(II
Glc
), exists in two physical forms, a membrane-integrated oligomeric form and a soluble monomeric form, which separate from each other on a gel filtration column (peaks 1 and 2, respectively). Western blot analyses using anti-His tag monoclonal antibodies revealed that although II
Glc
from the two fractions migrated similarly in sodium dodecyl sulfate gels, the two fractions migrated differently on native gels both before and after Triton X-100 treatment. Peak 1 II
Glc
migrated much more slowly than peak 2 II
Glc
. Both preparations exhibited both phosphoenolpyruvate-dependent sugar phosphorylation activity and sugar phosphate-dependent sugar transphosphorylation activity. The kinetics of the transphosphorylation reaction catalyzed by the two II
Glc
fractions were different: peak 1 activity was subject to substrate inhibition, while peak 2 activity was not. Moreover, the pH optima for the phosphoenolpyruvate-dependent activities differed for the two fractions. The results provide direct evidence that the two forms of II
Glc
differ with respect to their physical states and their catalytic activities. These general conclusions appear to be applicable to the His-tagged mannose permease of
E. coli
. Thus, both phosphoenolpyruvate-dependent phosphotransferase system enzymes exist in soluble and membrane-integrated forms that exhibit dissimilar physical and kinetic properties.
Large-Scale Identification of Genes Required for Full Virulence ofStaphylococcus aureus
Authors: Benton Bret M. , Zhang J. P. , Bond Skip , Pope Casey , Christian Todd , Lee Lawrence , Winterberg Kelly M. , Schmid Molly B. , Buysse Jerry M. 
Published: December 2004

ABSTRACTGene products required for in vivo growth and survival of microbial pathogens comprise a unique functional class and may represent new targets for antimicrobial chemotherapy, vaccine construction, or diagnostics. Although some factors governingStaphylococcus aureuspathogenicity have been identified and studied, a comprehensive genomic analysis of virulence functions will be a prerequisite for developing a global understanding of interactions between this pathogen and its human host. In this study, we describe a genetic screening strategy and demonstrate its use in screening a collection of 6,300S. aureusinsertion mutants for virulence attenuation in a murine model of systemic infection. Ninety-five attenuated mutants were identified, reassembled into new pools, and rescreened using the same murine model. This effort identified 24 highly attenuated mutants, each of which was further characterized for virulence attenuation in vivo and for growth phenotypes in vitro. Mutants were recovered in numbers up to 1,200-fold less than wild type in the spleens of systemically infected animals and up to 4,000-fold less than wild type in localized abscess infections. Genetic analysis of the mutants identified insertions in 23 unique genes. The largest gene classes represented by these mutants encoded enzymes involved in small-molecule biosynthesis and cell surface transmembrane proteins involved in small-molecule binding and transport. Additionally, three insertions defined two histidine kinase sensor-response regulator gene pairs important forS. aureusin vivo survival. Our findings extend the understanding of pathogenic mechanisms employed byS. aureusto ensure its successful growth and survival in vivo. Many of the gene products we have identified represent attractive new targets for antibacterial chemotherapy.