35 research outputs found
A destabilized bacterial luciferase for dynamic gene expression studies
Fusions of genetic regulatory elements with reporter genes have long been used as tools for monitoring gene expression and have become a major component in synthetic gene circuit implementation. A major limitation of many of these systems is the relatively long half-life of the reporter protein(s), which prevents monitoring both the initiation and the termination of transcription in real-time. Furthermore, when used as components in synthetic gene circuits, the long time constants associated with reporter protein decay may significantly degrade circuit performance. In this study, short half-life variants of LuxA and LuxB from Photorhabdus luminescens were constructed in Escherichia coli by inclusion of an 11-amino acid carboxy-terminal tag that is recognized by endogenous tail-specific proteases. Results indicated that the addition of the C-terminal tag affected the functional half-life of the holoenzyme when the tag was added to luxA or to both luxA and luxB, but modification of luxB alone did not have a significant effect. In addition, it was also found that alteration of the terminal three amino acid residues of the carboxy-terminal tag fused to LuxA generated variants with half-lives of intermediate length in a manner similar to that reported for GFP. This report is the first instance of the C-terminal tagging approach for the regulation of protein half-life to be applied to an enzyme or monomer of a multi-subunit enzyme complex and will extend the utility of the bacterial luciferase reporter genes for the monitoring of dynamic changes in gene expression
CD4+ T Cell Effects on CD8+ T Cell Location Defined Using Bioluminescence
T lymphocytes of the CD8+ class are critical in delivering cytotoxic function and in controlling viral and intracellular infections. These cells are “helped” by T lymphocytes of the CD4+ class, which facilitate their activation, clonal expansion, full differentiation and the persistence of memory. In this study we investigated the impact of CD4+ T cells on the location of CD8+ T cells, using antibody-mediated CD4+ T cell depletion and imaging the antigen-driven redistribution of bioluminescent CD8+ T cells in living mice. We documented that CD4+ T cells influence the biodistribution of CD8+ T cells, favoring their localization to abdominal lymph nodes. Flow cytometric analysis revealed that this was associated with an increase in the expression of specific integrins. The presence of CD4+ T cells at the time of initial CD8+ T cell activation also influences their biodistribution in the memory phase. Based on these results, we propose the model that one of the functions of CD4+ T cell “help” is to program the homing potential of CD8+ T cells
Effects of perceptions of information overload, noise and environmental demands on wellbeing and academic attainment.
The present research considers components of information overload, which may have a negative impact on wellbeing and academic attainment. 179 university students completed a survey consisting of an information overload scale (IOS) and the wellbeing process questionnaire. Their academic attainment scores were also added to the database. The IOS scale also included questions relating to noise exposure. Both the noise scores and non-noise IOS scores were associated with greater negative wellbeing and lower positive wellbeing. There were no significant effects of noise or IOS scores on academic attainment. Wellbeing is predicted by a number of factors such as exposure to stressors, negative coping, social support and psychological capital. When these established factors were included in the analyses, the effects of noise and other aspects of IOS could be accounted for by exposure to other stressors and were no longer significant predictors of negative or positive wellbeing
Recommended from our members
Physician-patient communication in rheumatology: a systematic review
The nature of physician–patient interaction can have a significant impact on patient outcomes through information-sharing and disease-specific education that can enhance patients’ active involvement in their care. The aim of this systematic review was to examine all the empirical evidence pertaining to aspects of physician–patient communication and its impact on patient outcomes. A systematic search of five electronic databases (MEDLINE, PsycINFO, EMBASE, CINAHL, and Web of Science) was undertaken from earliest record to December 2016. Studies were eligible if they: (1) included adult participants (18 years or over) with a diagnosis of a rheumatic condition; (2) were of quantitative, qualitative or mixed methods design; (4) were surveys, observational and interventional studies; (5) were published in the English language; and (6) reported findings on either various physician–patient communication aspects alone or in combination with physical and psychological outcomes. Searches identified 455 papers. Following full-text retrieval and assessment for eligibility and quality, ten studies were included in the review; six quantitative, one mixed methods, and three qualitative papers. Higher levels of trust in the physician and active patient participation in the medical consultation were linked to lower disease activity, better global health, less organ damage accrual, greater treatment satisfaction with fewer side effects from the medication, more positive beliefs about control over the disease, and about current and future health. Future research could focus on the design and implementation of interventions incorporating communications skills and patient-education training
Reporting Effects of SFAS 143 on Nuclear Decommissioning Costs
SFAS 143, Accounting for Asset Retirement Obligations, has the potential to cause significant economic consequences to firms impacted by its provisions. BK&L (Boatsman, J. R.; Khurana, I. K.; Loudder, M. L. “The Economic Implications of Proposed Changes in the Accounting for Nuclear Decommissioning Costs,” Accounting Horizons, 14 (2), June 2000, pp. 211–233) suggests that companies would be required to record materially increased assets, liabilities, and expenses which may subsequently cause a significant impact to commonly used financial ratios. BK&L developed predictions of the pro forma effect on assets, liabilities, and expenses due to SFAS 143 adoption by nuclear power utilities. This study examines the actual financial statement effect on BK&L's sample firms due to the adoption of SFAS 143. Results indicate that concern voiced over the standard's requirement to capitalize asset retirement obligations and the related asset, and to record additional expenses by nuclear power companies may have been unfounded. Copyright International Atlantic Economic Society 2005M41,
Infection prophylaxis patterns following pediatric autologous hematopoietic stem cell transplantation: A survey of Pediatric Transplant and Cell Therapy Consortium centers
No standardized guidelines exist for infectious prophylaxis following pediatric auto‐HSCT. We hypothesized significant variation in clinical practice. Thirty‐three Pediatric Transplant and Cell Therapy Consortium centers completed a survey to assess institutional management. The majority utilize viral (91%) and fungal prophylaxis (94%), but duration varies. Bacterial prophylaxis during neutropenia is instituted by 42%. Our study demonstrates marked practice variability in infectious prophylaxis across centers. Additional research is needed to address patterns of infectious complications and to develop meaningful clinical practice guidelines for pediatric auto‐HSCT.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163606/3/petr13821.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163606/2/petr13821_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163606/1/petr13821-sup-0001-FigS1.pd