A review of sedation scales for the cardiac catheterization laboratory

Sedation scales have the potential to facilitate effective procedural sedation and analgesia in the cardiac catheterization laboratory (CCL). For this potential to become realised, a scale that is suitable for use in the CCL either needs to be identified or developed. To identify sedation scales, a review of Medline and CINHAL was conducted. One sedation scale for the CCL, the NASPE SED, and 15 Intensive Care Unit (ICU) scales met the inclusion and exclusion criteria. Analysis of the scale’s item structures and psychometric properties was then performed. None of these scales were deemed suitable for use in the CCL. As such, further research is required to develop a new scale. The new scale should consist of more than one item because it will be the most effective for tracking the patient’s response to medications. Specific tests required to conduct a rigorous evaluation of the new scale’s psychometric properties are outlined in this paper.

Computer-assisted measurements of coronal knee joint laxity in vitro are related to low-stress behavior rather than structural properties of the collateral ligaments

The relationship between coronal knee laxity and the restraining properties of the collateral ligaments remains unknown. This study investigated correlations between the structural properties of the collateral ligaments and stress angles used in computer-assisted total knee arthroplasty (TKA), measured with an optically based navigation system. Ten fresh-frozen cadaveric knees (mean age: 81 ± 11 years) were dissected to leave the menisci, cruciate ligaments, posterior joint capsule and collateral ligaments. The resected femur and tibia were rigidly secured within a test system which permitted kinematic registration of the knee using a commercially available image-free navigation system. Frontal plane knee alignment and varus-valgus stress angles were acquired. The force applied during varus-valgus testing was quantified. Medial and lateral bone-collateral ligament-bone specimens were then prepared, mounted within a uni-axial materials testing machine, and extended to failure. Force and displacement data were used to calculate the principal structural properties of the ligaments. The mean varus laxity was 4 ± 1° and the mean valgus laxity was 4 ± 2°. The corresponding mean manual force applied was 10 ± 3 N and 11 ± 4 N, respectively. While measures of knee laxity were independent of the ultimate tensile strength and stiffness of the collateral ligaments, there was a significant correlation between the force applied during stress testing and the instantaneous stiffness of the medial (r = 0.91, p = 0.001) and lateral (r = 0.68, p = 0.04) collateral ligaments. These findings suggest that clinicians may perceive a rate of change of ligament stiffness as the end-point during assessment of collateral knee laxity.

The impact of spatial scales and spatial smoothing on the outcome of Bayesian spatial model

Discretization of a geographical region is quite common in spatial analysis. There have been few studies into the impact of different geographical scales on the outcome of spatial models for different spatial patterns. This study aims to investigate the impact of spatial scales and spatial smoothing on the outcomes of modelling spatial point-based data. Given a spatial point-based dataset (such as occurrence of a disease), we study the geographical variation of residual disease risk using regular grid cells. The individual disease risk is modelled using a logistic model with the inclusion of spatially unstructured and/or spatially structured random effects. Three spatial smoothness priors for the spatially structured component are employed in modelling, namely an intrinsic Gaussian Markov random field, a second-order random walk on a lattice, and a Gaussian field with Matern correlation function. We investigate how changes in grid cell size affect model outcomes under different spatial structures and different smoothness priors for the spatial component. A realistic example (the Humberside data) is analyzed and a simulation study is described. Bayesian computation is carried out using an integrated nested Laplace approximation. The results suggest that the performance and predictive capacity of the spatial models improve as the grid cell size decreases for certain spatial structures. It also appears that different spatial smoothness priors should be applied for different patterns of point data.

Identification and occupational stress : a stress-buffering perspective

Occupational stress research has consistently demonstrated many negative effects of work stressors on employee adjustment (i.e., job-related attitudes and health). Considerable literature also describes potential moderators of this relationship. While research has revealed that different workplace identifications can have significant positive effects on employee adjustment, it has neglected to investigate their potential stress-buffering effects. Based on identity theories, it was predicted that stress-buffering effects of different types of identifications (distal versus proximal) would be revealed when the identification type and employee adjustment outcome type (distal versus proximal) were congruent. Predictions were tested with an employee sample from five human service nonprofit organizations (N = 337). Hierarchical multiple regression analyses revealed that main and moderated effects relating to identification supported the notion that occupational stress would be reduced when there was congruence of distal and proximal identifications and distal and proximal outcome types. However, stress-buffering effects were also found for high identifiers and low identifiers that were not in line with hypotheses posing questions for the definitions of distal and proximal identifications. Findings are discussed in terms of theoretical and practical implications.

A longitudinal study of the impact of chronic psychological stress on health-related quality of life and clinical biomarkers : protocol for the Australian Healthy Aging of Women Study

BACKGROUND: Despite advancements in our understanding of the importance of stress reduction in achieving good health, we still only have limited insight into the impact of stress on cellular function. Recent studies have suggested that exposure to prolonged psychological stress may alter an individual's physiological responses, and contribute to morbidity and mortality. This paper presents an overview of the study protocol we are using to examine the impact of life stressors on lifestyle factors, health-related quality of life and novel and established biomarkers of stress in midlife and older Australian women.The primary aim of this study is to explore the links between chronic psychological stress on both subjective and objective health markers in midlife and older Australian women. The study examines the extent to which exposure frightening, upsetting or stressful events such as natural disasters, illness or death of a relative, miscarriage and relationship conflict is correlated with a variety of objective and subjective health markers.Methods/design: This study is embedded within the longitudinal Healthy Aging of Women's study which has collected data from midlife and older Australian women at 5 yearly intervals since 2001, and uses the Allostastic model of women's health by Groer and colleagues in 2010. The current study expands the focus of the HOW study and will assess the impact of life stressors on quality of life and clinical biomarkers in midlife and older Australian women to explain the impact of chronic psychological stress in women. DISCUSSION: The proposed study hypothesizes that women are at increased risk of exposure to multiple or repeated stressors, some being unique to women, and the frequency and chronicity of stressors increases women's risk of adverse health outcomes. This study aims to further our understanding of the relationships between stressful life experiences, perceived quality of life, stress biomarkers, chronic illness, and health status in women.

Correlating flow induced shear stress and chondrocytes activity in micro-porous scaffold using computational fluid dynamics and rapid prototyping

Flow induced shear stress plays an important role in regulating cell growth and distribution in scaffolds. This study sought to correlate wall shear stress and chondrocytes activity for engineering design of micro-porous osteochondral grafts based on the hypothesis that it is possible to capture and discriminate between the transmitted force and cell response at the inner irregularities. Unlike common tissue engineering therapies with perfusion bioreactors in which flow-mediated stress is the controlling parameter, this work assigned the associated stress as a function of porosity to influence in vitro proliferation of chondrocytes. D-optimality criterion was used to accommodate three pore characteristics for appraisal in a mixed level fractional design of experiment (DOE); namely, pore size (4 levels), distribution pattern (2 levels) and density (3 levels). Micro-porous scaffolds (n=12) were fabricated according to the DOE using rapid prototyping of an acrylic-based bio-photopolymer. Computational fluid dynamics (CFD) models were created correspondingly and used on an idealized boundary condition with a Newtonian fluid domain to simulate the dynamic microenvironment inside the pores. In vitro condition was reproduced for the 3D printed constructs seeded by high pellet densities of human chondrocytes and cultured for 72 hours. The results showed that cell proliferation was significantly different in the constructs (p<0.05). Inlet fluid velocity of 3×10-2mms-1 and average shear stress of 5.65×10-2 Pa corresponded with increased cell proliferation for scaffolds with smaller pores in hexagonal pattern and lower densities. Although the analytical solution of a Poiseuille flow inside the pores was found insufficient for the description of the flow profile probably due to the outside flow induced turbulence, it showed that the shear stress would increase with cell growth and decrease with pore size. This correlation demonstrated the basis for determining the relation between the induced stress and chondrocyte activity to optimize microfabrication of engineered cartilaginous constructs.

Local stress-strain distribution and load transfer across cartilage matrix at micro-scale using combined microscopy-based finite element method

Articular cartilage is the load-bearing tissue that consists of proteoglycan macromolecules entrapped between collagen fibrils in a three-dimensional architecture. To date, the drudgery of searching for mathematical models to represent the biomechanics of such a system continues without providing a fitting description of its functional response to load at micro-scale level. We believe that the major complication arose when cartilage was first envisaged as a multiphasic model with distinguishable components and that quantifying those and searching for the laws that govern their interaction is inadequate. To the thesis of this paper, cartilage as a bulk is as much continuum as is the response of its components to the external stimuli. For this reason, we framed the fundamental question as to what would be the mechano-structural functionality of such a system in the total absence of one of its key constituents-proteoglycans. To answer this, hydrated normal and proteoglycan depleted samples were tested under confined compression while finite element models were reproduced, for the first time, based on the structural microarchitecture of the cross-sectional profile of the matrices. These micro-porous in silico models served as virtual transducers to produce an internal noninvasive probing mechanism beyond experimental capabilities to render the matrices micromechanics and several others properties like permeability, orientation etc. The results demonstrated that load transfer was closely related to the microarchitecture of the hyperelastic models that represent solid skeleton stress and fluid response based on the state of the collagen network with and without the swollen proteoglycans. In other words, the stress gradient during deformation was a function of the structural pattern of the network and acted in concert with the position-dependent compositional state of the matrix. This reveals that the interaction between indistinguishable components in real cartilage is superimposed by its microarchitectural state which directly influences macromechanical behavior.

Foot massage and physiological stress in people with dementia : a randomized controlled trial

Background There is increasing interest in using complementary and alternative treatments to manage behavioural and psychological symptoms of dementia such as agitation, aggression and depressed mood. Objective To compare the effect of foot massage (intervention) and quiet presence (control) on agitation and mood in people with dementia. Design A randomised controlled trial using a within-subjects, crossover design. Settings Five long-term care facilities in Brisbane, Australia. The primary outcome was the Cohen-Mansfield Agitation Inventory (CMAI) and the secondary outcome was the Observed Emotion Rating Scale (OERS). The screening and data collection research assistants, families, and care staff were blinded to participant allocation. Participants Participants of the study were 55 long-term care residents aged 74–103 years (mean age 86.5), with moderate to severe dementia and a history of agitated behaviour according to the Pittsburgh Agitation Scale. A computer-program randomised participants to 10-min foot massage (intervention) or quiet presence (control), every weekday for 3 weeks. Results A carry-over effect was identified in the data, and so the data was treated as a parallel groups RCT. The mean total CMAI increased in both groups (reflecting an increase in agitation) with this increase greater in the quiet presence group than the foot massage group (p=0.03). There was a trend towards a difference on OERS General Alertness, with a positive change in alertness for participants in the foot massage group (indicating reduced alertness) and a negative change for participants in the quiet presence group (indicating increased alertness) (F(1,51)=3.88, p=0.05, partial ή2=0.07). Conclusions The findings highlight the need for further research on the specific conditions under which massage might promote relaxation and improve mood for people with dementia. The unfamiliar research assistants and variations in usual activity may have contributed to the increase in agitation and this needs further research.

Towards bio-inspired place recognition over multiple spatial scales

This paper presents a new multi-scale place recognition system inspired by the recent discovery of overlapping, multi-scale spatial maps stored in the rodent brain. By training a set of Support Vector Machines to recognize places at varying levels of spatial specificity, we are able to validate spatially specific place recognition hypotheses against broader place recognition hypotheses without sacrificing localization accuracy. We evaluate the system in a range of experiments using cameras mounted on a motorbike and a human in two different environments. At 100% precision, the multiscale approach results in a 56% average improvement in recall rate across both datasets. We analyse the results and then discuss future work that may lead to improvements in both robotic mapping and our understanding of sensory processing and encoding in the mammalian brain.

Assessing the construct validity and reliability of the parental perception on antibiotics (PAPA) scales

Background: The overuse of antibiotics is becoming an increasing concern. Antibiotic resistance, which increases both the burden of disease, and the cost of health services, is perhaps the most profound impact of antibiotics overuse. Attempts have been made to develop instruments to measure the psychosocial constructs underlying antibiotics use, however, none of these instruments have undergone thorough psychometric validation. This study evaluates the psychometric properties of the Parental Perceptions on Antibiotics (PAPA) scales. The PAPA scales attempt to measure the factors influencing parental use of antibiotics in children. Methods: 1111 parents of children younger than 12 years old were recruited from primary schools’ parental meetings in the Eastern Province of Saudi Arabia from September 2012 to January 2013. The structure of the PAPA instrument was validated using Confirmatory Factor Analysis (CFA) with measurement model fit evaluated using the raw and scaled χ2, Goodness of Fit Index, and Root Mean Square Error of Approximation. Results: A five-factor model was confirmed with the model showing good fit. Constructs in the model include: Knowledge and Beliefs, Behaviors, Sources of information, Adherence, and Awareness about antibiotics resistance. The instrument was shown to have good internal consistency, and good discriminant and convergent validity. Conclusion: The availability of an instrument able to measure the psychosocial factors underlying antibiotics usage allows the risk factors underlying antibiotic use and overuse to now be investigated.

Stress, lifestyle and quality of life in midlife and older Australian women : results from the stress and the health of women study

Background Chronic psychological stress may pose a serious threat to health, although the mechanisms are not fully understood. This study examines the impact of stress on modifiable lifestyle factors, depressive symptoms, health-related quality of life (HRQOL) and chronic illness in older Australian women. Methods Cross-sectional data were collected from a random sample of 181 older adults aged 60-70 years from rural and urban areas of South-East Queensland, Australia. We used structural equation modelling to examine associations between stress, modifiable lifestyle factors, HRQoL, and chronic illness. Findings Parameter estimates show that older women who reported life stressors where they felt helpless and feared for their life (high magnitude stressors) also reported higher body mass index (p = 0.03) and more chronic illness (p <0.01). In contrast, duration of exposure to life stressors was associated with higher depressive symptom scores (CES-D, p = 0.02) and sleep disturbance scores (p <0.01). Conclusions Our findings support the link between traumatic personal histories (exposure to high magnitude stressors) and unhealthy lifestyle factors. Findings highlight the need for more research on how stress reduction healthy lifestyle and positive coping strategies can be used to reduce the effects of high magnitude stress on health-related quality of life and chronic illness.

Cellular stress triggers the human topoisomerase I damage response independently of DNA damage in a p53 controlled manner

The 'human topoisomerase I (htopoI) damage response' was reported to be triggered by various kinds of DNA lesions. Also, a high and persistent level of htopoI cleavage complexes correlated with apoptosis. In the present study, we demonstrate that DNA damage-independent induction of cell death using colcemid and tumor necrosis factor is also accompanied by a strong htopoI response that correlates with the onset of apoptotic hallmarks. Consequently, these results suggest that htopoI cleavage complex formation may be caused by signaling pathways independent of the kind of cellular stress. Thus, protein interactions or signaling cascades induced by DNA damage or cellular stress might lead to the formation of stabilized cleavage complexes rather than the DNA lesion itself. Finally, we show that p53 not only plays a key role in the regulation of the htopoI response to UV-C irradiation but also to treatment with colcemid.

The role of the glucocorticoids in developing resilience to stress and addiction

There is emerging evidence that individuals have the capacity to learn to be resilient by developing protective mechanisms that prevent them from the maladaptive effects of stress that can contribute to addiction.The emerging field of the neuroscience of resilience is beginning to uncover the circuits and molecules that protect against stress-related neuropsychiatric diseases, such as addiction. Glucocorticoids (GCs) are important regulators of basal and stress-related homeostasis in all higher organisms and influence a wide array of genes in almost every organ and tissue. GCs, therefore, are ideally situated to either promote or prevent adaptation to stress. In this review, we will focus on the role of GCs in the hypothalamic-pituitary adrenocortical axis and extra-hypothalamic regions in regulating basal and chronic stress responses. GCs interact with a large number of neurotransmitter and neuropeptide systems that are associated with the development of addiction. Additionally, the review will focus on the orexinergic and cholinergic pathways and highlight their role in stress and addiction. GCs play a key role in promoting the development of resilience or susceptibility and represent important pharmacotherapeutic targets that can reduce the impact of a maladapted stress system for the treatment of stress-induced addiction.

Biological markers of stress in pediatric acute burn injury

BACKGROUND Burns and their associated wound care procedures evoke significant stress and anxiety, particularly for children. Little is known about the body's physiological stress reactions throughout the stages of re-epithelialization following an acute burn injury. Previously, serum and urinary cortisol have been used to measure stress in burn patients, however these measures are not suitable for a pediatric burn outpatient setting. AIM To assess the sensitivity of salivary cortisol and sAA in detecting stress during acute burn wound care procedures and to investigate the body's physiological stress reactions throughout burn re-epithelialization. METHODS Seventy-seven participants aged four to thirteen years who presented with an acute burn injury to the burn center at the Royal Children's Hospital, Brisbane, Australia, were recruited between August 2011 and August 2012. RESULTS Both biomarkers were responsive to the stress of burn wound care procedures. sAA levels were on average 50.2U/ml higher (p<0.001) at 10min post-dressing removal compared to baseline levels. Salivary cortisol levels showed a blunted effect with average levels at ten minutes post dressing removal decreasing by 0.54nmol/L (p<0.001) compared to baseline levels. sAA levels were associated with pain (p=0.021), no medication (p=0.047) and Child Trauma Screening Questionnaire scores at three months post re-epithelialization (p=0.008). Similarly, salivary cortisol was associated with no medication (p<0.001), pain scores (p=0.045) and total body surface area of the burn (p=0.010). CONCLUSION Factors which support the use of sAA over salivary cortisol to assess stress during morning acute burn wound care procedures include; sensitivity, morning clinic times relative to cortisol's diurnal peaks, and relative cost.

Bcl-X(L) translocation in renal tubular epithelial cells in vitro protects distal cells from oxidative stress

BACKGROUND: The molecular pathogenesis of different sensitivities of the renal proximal and distal tubular cell populations to ischemic injury, including ischemia-reperfusion (IR)-induced oxidative stress, is not well-defined. An in vitro model of oxidative stress was used to compare the survival of distal [Madin-Darby canine kidney (MDCK)] and proximal [human kidney-2 (HK-2)] renal tubular epithelial cells, and to analyze for links between induced cell death and expression and localization of selected members of the Bcl-2 gene family (anti-apoptotic Bcl-2 and Bcl-X(L), pro-apoptotic Bax and Bad). METHODS: Cells were treated with 1 mmol/L hydrogen peroxide (H2O2) or were grown in control medium for 24 hours. Cell death (apoptosis) was quantitated using defined morphological criteria. DNA gel electrophoresis was used for biochemical identification. Protein expression levels and cellular localization of the selected Bcl-2 family proteins were analyzed (Western immunoblots, densitometry, immunoelectron microscopy). RESULTS: Apoptosis was minimal in control cultures and was greatest in treated proximal cell cultures (16.93 +/- 4.18% apoptosis) compared with treated distal cell cultures (2.28 +/- 0.85% apoptosis, P < 0.001). Endogenous expression of Bcl-X(L) and Bax, but not Bcl-2 or Bad, was identified in control distal cells. Bcl-X(L) and Bax had nonsignificant increases (P> 0.05) in these cells. Bcl-2, Bax, and Bcl-X(L), but not Bad, were endogenously expressed in control proximal cells. Bcl-X(L) was significantly decreased in treated proximal cultures (P < 0.05), with Bax and Bcl-2 having nonsignificant increases (P> 0.05). Immunoelectron microscopy localization indicated that control and treated but surviving proximal cells had similar cytosolic and membrane localization of the Bcl-2 proteins. In comparison, surviving cells in the treated distal cultures showed translocation of Bcl-X(L) from cytosol to the mitochondria after treatment with H2O2, a result that was confirmed using cell fractionation and analysis of Bcl-X(L) expression levels of the membrane and cytosol proteins. Bax remained distributed evenly throughout the surviving distal cells, without particular attachment to any cellular organelle. CONCLUSION: The results indicate that in this in vitro model, the increased survival of distal compared with proximal tubular cells after oxidative stress is best explained by the decreased expression of anti-apoptotic Bcl-X(L) in proximal cells, as well as translocation of Bcl-X(L) protein to mitochondria within the surviving distal cells.