Thermodynamic stability of wild-type and mutant p53 core domain

Some 50% of human cancers are associated with mutations in the core domain of the tumor suppressor p53. Many mutations are thought just to destabilize the protein. To assess this and the possibility of rescue, we have set up a system to analyze the stability of the core domain and its mutants. The use of differential scanning calorimetry or spectroscopy to measure its melting temperature leads to irreversible denaturation and aggregation and so is useful as only a qualitative guide to stability. There are excellent two-state denaturation curves on the addition of urea that may be analyzed quantitatively. One Zn²⁺ ion remains tightly bound in the holo-form of p53 throughout the denaturation curve. The stability of wild type is 6.0 kcal (1 kcal = 4.18 kJ)/mol at 25°C and 9.8 kcal/mol at 10°C. The oncogenic mutants R175H, C242S, R248Q, R249S, and R273H are destabilized by 3.0, 2.9, 1.9, 1.9, and 0.4 kcal/mol, respectively. Under certain denaturing conditions, the wild-type domain forms an aggregate that is relatively highly fluorescent at 340 nm on excitation at 280 nm. The destabilized mutants give this fluorescence under milder denaturation conditions.     

Calcium-sensing soluble adenylyl cyclase mediates TNF signal transduction in human neutrophils

Through chemical screening, we identified a pyrazolone that reversibly blocked the activation of phagocyte oxidase (phox) in human neutrophils in response to tumor necrosis factor (TNF) or formylated peptide. The pyrazolone spared activation of phox by phorbol ester or bacteria, bacterial killing, TNF-induced granule exocytosis and phox assembly, and endothelial transmigration. We traced the pyrazolone's mechanism of action to inhibition of TNF-induced intracellular Ca2+ elevations, and identified a nontransmembrane ("soluble") adenylyl cyclase (sAC) in neutrophils as a Ca2+-sensing source of cAMP. A sAC inhibitor mimicked the pyrazolone's effect on phox. Both compounds blocked TNF-induced activation of Rap1A, a phox-associated guanosine triphosphatase that is regulated by cAMP. Thus, TNF turns on phox through a Ca2+-triggered, sAC-dependent process that may involve activation of Rap1A. This pathway may offer opportunities to suppress oxidative damage during inflammation without blocking antimicrobial function.     

A systematic review of teamwork in the intensive care unit: What do we know about teamwork,team tasks,and improvement strategies?

Purpose

Teamwork is essential for ensuring the quality and safety of health care delivery in the intensive care unit (ICU). This article addresses what we know about teamwork, team tasks, and team improvement strategies in the ICU to identify the strengths and limitations of the existing knowledge base to guide future research.

Methods

A keyword search of the PubMed database was conducted in February 2013. Keyword combinations focused on 3 areas: (1) teamwork, (2) the ICU, and (3) training/quality improvement interventions. All studies that investigated teamwork, team tasks, or team interventions within the ICU (ie, intradepartment) were selected for inclusion.

Results

Teamwork has been investigated across an array of research contexts and task types. The terminology used to describe team factors varied considerably across studies. The most common team tasks involved strategy and goal formulation. Team training and structured protocols were the most widely implemented quality improvement strategies.

Conclusions

Team research is burgeoning in the ICU, yet low-hanging fruit remains that can further advance the science of teams in the ICU if addressed. Constructs must be defined, and theoretical frameworks should be referenced. The functional characteristics of tasks should also be reported to help determine the extent to which study results might generalize to other contexts of work.     

Relationship between a Centers for Disease Control and Prevention expanded HIV testing initiative and past-year testing by race/ethnicity: a multilevel analysis of the Behavioral Risk Factor Surveillance System

The Centers for Disease Control and Prevention's (CDC) expanded testing initiative (ETI) aims to bolster HIV testing among populations disproportionately affected by the HIV epidemic by providing additional funding to health departments serving these communities. ETI prioritizes testing in clinical settings; therefore, we examined the relationship between state-level ETI participation and past-year HIV testing among a racially/ethnically diverse sample of adult respondents to the 2012 Behavioral Risk Factor Surveillance System who accessed health services within the 12 months prior to being interviewed. Controlling for individual- and state-level characteristics in a multilevel logistic regression model, ETI participation was independently and positively associated with past-year testing, but this association varied by race/ethnicity. Hispanics had higher odds (adjusted odds ratio [AOR]: 1.49; 95% CI: 1.11–2.02) and American Indian/Alaska Natives had lower odds (AOR: 0.66; 95% CI: 0.43–0.99) of testing if they resided in states with (vs. without) ETI participation. State-level ETI participation did not significantly alter past-year testing among other racial/ethnic groups. Prioritizing public health resources in states most affected by HIV can improve testing patterns, but other mechanisms likely influence which racial/ethnic groups undergo testing.     

Association Between Pretreatment Sleep Disturbance and Radiation Therapy-Induced Pain in 573 Women With Breast Cancer

ContextPain can be a debilitating side effect of radiation therapy (RT). Data from the general population have shown that sleep disturbance can influence pain incidence and severity; however, less is known about this relationship in patients with breast cancer receiving RT.ObjectivesThis secondary analysis examined the association of pretreatment moderate/severe levels of sleep disturbance with subsequent RT-induced pain after adjusting for pre-RT pain.MethodsWe report on 573 female patients with breast cancer undergoing RT from a previously completed Phase II clinical trial for radiation dermatitis. Sleep disturbance, total pain, and pain subdomains—sensory pain, affective pain, and perceived pain intensity were assessed at pre-RT and post-RT. At pre-RT, patients were dichotomized into two groups: those with moderate/severe sleep disturbance (N = 85) vs. those with no/mild sleep disturbance (control; N = 488).ResultsAt pre-RT, women with moderate/severe sleep disturbance were younger, less likely to be married, more likely to have had mastectomy and chemotherapy, and more likely to have depression/anxiety disorder and fatigue than the control group (all Ps < 0.05). Generalized estimating equations model, after controlling for pre-RT pain and other covariates (e.g., trial treatment condition and covariates that were significantly correlated with post-RT pain), showed that women with moderate/severe sleep disturbance at pre-RT vs. control group had significantly higher mean post-RT total pain as well as sensory, affective, and perceived pain (effect size = 0.62, 0.60, 0.69, and 0.52, respectively; all Ps < 0.05).ConclusionThese findings suggest that moderate/severe disturbed sleep before RT is associated with increased pain from pre-to-post-RT in patients with breast cancer.     

Aromatherapy Hand Massage for Test Anxiety and Self-Efficacy in Nursing Students: A Pilot Study

The purpose of this study was to determine if aromatherapy hand massage (HM) could improve test anxiety and self-efficacy in nursing students. Participants were randomized to receive aromatherapy hand massage (AHM), unscented HM, or no intervention (C) 60 minutes before an examination. No significant differences were found, but analysis of the percentage change from the means demonstrated the largest decrease in test anxiety in the AHM group (AHM = ?12.4%, HM = ?8.63%, C = ?1.76%). Self-efficacy trends followed a similar pattern (AHM = 5.93%, HM = ?3.03%, C = 0.52%). The trends in the percentage change from the means indicate that a larger sample may show improvements in test anxiety and self-efficacy with the use of AHM, which could improve nursing students’ academic performance and decrease attrition rates.