Analysing the similarity of proteins based on a new approach to empirical mode decomposition

The function of a protein can be partially determined by the information contained in its amino acid sequence. It can be assumed that proteins with similar amino acid sequences normally have closer functions. Hence analysing the similarity of proteins has become one of the most important areas of protein study. In this work, a layered comparison method is used to analyze the similarity of proteins. It is based on the empirical mode decomposition (EMD) method, and protein sequences are characterized by the intrinsic mode functions (IMFs). The similarity of proteins is studied with a new cross-correlation formula. It seems that the EMD method can be used to detect the functional relationship of two proteins. This kind of similarity method is a complement of traditional sequence similarity approaches which focus on the alignment of amino acids

Stress at the synapse : signal transduction mechanisms of adrenal steroids at neuronal membranes

As the key neuron-to-neuron interface, the synapse is involved in learning and memory, including traumatic memories during times of stress. However, the signal transduction mechanisms by which stress mediates its lasting effects on synapse transmission and on memory are not fully understood. A key component of the stress response is the increased secretion of adrenal steroids. Adrenal steroids (e.g., cortisol) bind to genomic mineralocorticoid and glucocorticoid receptors (gMRs and gGRs) in the cytosol. In addition, they may act through membrane receptors (mMRs and mGRs), and signal transduction through these receptors may allow for rapid modulation of synaptic transmission as well as modulation of membrane ion currents. mMRs increase synaptic and neuronal excitability; mechanisms include the facilitation of glutamate release through extracellular signal-regulated kinase signal transduction. In contrast, mGRs decrease synaptic and neuronal excitability by reducing calcium currents through N-methyl-D-aspartate receptors and voltage-gated calcium channels by way of protein kinase A- and G protein-dependent mechanisms. This body of functional data complements anatomical evidence localizing GRs to the postsynaptic membrane. Finally, accumulating data also suggest the possibility that mMRs and mGRs may show an inverted U-shaped dose response, whereby glutamatergic synaptic transmission is increased by low doses of corticosterone acting at mMRs and decreased by higher doses acting at mGRs. Thus, synaptic transmission is regulated by mMRs and mGRs, and part of the stress signaling response is a direct and bidirectional modulation of the synapse itself by adrenal steroids.

Balancing the books : an assessment of financial stress associated with social work and human service student placements

This report presents the findings from a study of the financial impact of work-integrated learning commonly referred to as 'placement' among social work and human services students. Based on a survey of 214 respondants, 14 in-depth interviews and two focus groups, the findings indicate that two thirds of the surveyed group felt tired and anxious about their experience of balancing paid work and placement, with 2 in 5 reporting their learning experience was compromised as a result. The significant implications and potential solutions are also discussed.

Study burden, academic stress and mental health among high school students in Vietnam

Pressure on children to succeed in high schools is a serious problem in Asian societies. The focus of this study in three provinces of Vietnam was to identify the thresholds at which supplementary study has positive or negative effects on mental health and academic achievement. The findings contribute evidence for parents, teachers and young people about optimal levels of supplementary study (2–3 hours per day) and the most beneficial mode (self-study versus cram classes and private tutors). The work will be used to inform policy makers about strategies to minimize harmful effects of study burden for high school students.

Interactive relationships among multiple dimensions of professional commitment: Implications for stress outcomes in lawyers

The purpose of this study was to examine the main and interactive effects of four dimensions of professional commitment on strain (i.e., depression, anxiety, perceived health status, and job dissatisfaction) for a sample of 176 law professionals. The study utilized a two-wave design in which professional commitment and strain were measured at Time 1 and strain was measured again at Time 2 (T2), 2 months later. A significant two-way interaction indicated that high affective commitment was related to less T2 job dissatisfaction only for lawyers with low accumulated costs. A significant four-way interaction indicated that high affective professional commitment was only related to fewer symptoms of T2 anxiety for lawyers with high normative professional commitment and both low limited alternatives and accumulated costs. A similar pattern of results emerged in regard to T2 perceived health status. The theoretical and practical implications of these results for career counselors are discussed.

Large-scale interlaboratory study to develop, analytically validate and apply highly multiplexed, quantitative peptide assays to measure cancer-relevant proteins in plasma

There is an increasing need in biology and clinical medicine to robustly and reliably measure tens-to-hundreds of peptides and proteins in clinical and biological samples with high sensitivity, specificity, reproducibility and repeatability. Previously, we demonstrated that LC-MRM-MS with isotope dilution has suitable performance for quantitative measurements of small numbers of relatively abundant proteins in human plasma, and that the resulting assays can be transferred across laboratories while maintaining high reproducibility and quantitative precision. Here we significantly extend that earlier work, demonstrating that 11 laboratories using 14 LC-MS systems can develop, determine analytical figures of merit, and apply highly multiplexed MRM-MS assays targeting 125 peptides derived from 27 cancer-relevant proteins and 7 control proteins to precisely and reproducibly measure the analytes in human plasma. To ensure consistent generation of high quality data we incorporated a system suitability protocol (SSP) into our experimental design. The SSP enabled real-time monitoring of LC-MRM-MS performance during assay development and implementation, facilitating early detection and correction of chromatographic and instrumental problems. Low to sub-nanogram/mL sensitivity for proteins in plasma was achieved by one-step immunoaffinity depletion of 14 abundant plasma proteins prior to analysis. Median intra- and inter-laboratory reproducibility was <20%, sufficient for most biological studies and candidate protein biomarker verification. Digestion recovery of peptides was assessed and quantitative accuracy improved using heavy isotope labeled versions of the proteins as internal standards. Using the highly multiplexed assay, participating laboratories were able to precisely and reproducibly determine the levels of a series of analytes in blinded samples used to simulate an inter-laboratory clinical study of patient samples. Our study further establishes that LC-MRM-MS using stable isotope dilution, with appropriate attention to analytical validation and appropriate quality c`ontrol measures, enables sensitive, specific, reproducible and quantitative measurements of proteins and peptides in complex biological matrices such as plasma.

Biophysical correlates of intrinsic and stress-induced morphological variability in lateral amygdaloid neurons: A computational study

Morphological and physiological characteristics of neurons located in the dorsolateral and two ventral subdivisions of the lateral amygdala (LA) have been compared in order to differentiate their roles in the formation and storage of fear memories (Alphs et al, SfN abs 623.1, 2003). Briefly, in these populations, significant differences are observed in input resistance, membrane time constant, firing frequency, dendritic tortuosity, numbers of primary dendrites, dendritic segments and dendritic nodes...

Acute restraint stress alters subsequent auditory fear conditioning in the rat

The neural basis of Pavlovian fear conditioning is well understood and depends upon neural processes within the amygdala. Stress is known to play a role in the modulation of fear-related behavior, including Pavlovian fear conditioning. Chronic restraint stress has been shown to enhance fear conditioning to discrete and contextual stimuli; however, the time course and extent of restraint that is essential for this modulation of fear learning remains unclear. Thus, we tested the extent to which a single exposure to 1 hr of restraint would alter subsequent auditory fear conditioning in rats.

What are the contributors to job satisfaction, stress and burnout for haemodialysis nurses?

Aim To review recent studies which identify the factors that contribute to stress, burnout and job satisfaction for nurses who are working in haemodialysis units. Background Regardless of where nurses work, stress, job burnout and dissatisfaction are known to cause high rates of nurse resignations and for many of those to leave the profession entirely. Understanding factors that contribute to job satisfaction, stress and burnout could increase haemodialysis nurse retention and improve health outcomes for people receiving haemodialysis. Evaluation Studies of job stress, burnout and satisfaction for nurses working in haemodialysis units published in English from January 2000 to December 2009 were identified. Specific inclusion criteria were developed resulting in eleven articles selected for this review. Key issues Specifically for haemodialysis nurses’ job stress and burnout was found to originate from two factors related to either patient care or organisations. Patient care factors included unrealistic patient expectations, progressive decline of a patient’s health, and violence and verbal abuse from patients. Organisational factors included shortage of time to complete tasks, lack of resources and unsupportive work environments. Increased job satisfaction for haemodialysis nurses was due to having job security, freedom to use one’s judgement and the quality of nurse/physician interactions. Conclusion Job stress and burnout are problematic for haemodialysis nurses. Instituting strategies which prevent and/or ameliorate stress or burnout could result in improved job satisfaction and also the retention of highly skilled haemodialysis nurses.

Stress during the rebuilding phase influenced mental health following two Queensland flood disasters more than the event itself

It has long been known that disasters can have mental health consequences such as increased rates of PTSD, depression and anxiety. While some research has shown that secondary stressors during the aftermath of a disaster can influence psychological outcomes, this aspect of the disaster experience has not been widely studied. This paper reports on two studies that investigated which aspects of the experience of being flooded were most predictive of mental health outcomes. The first study was a qualitative study of adults whose homes had been inundated in the Mackay flood of 2008 (n=16). Thematic analysis of interviews conducted 18-20 months post-flood found that stressors during the flood aftermath such as difficulties and delays during the rebuilding process and a difficult experience with an insurance company were nominated as the most stressful aspect of the flood by the majority of participants. The second study surveyed Mackay flood survivors three and a half years post-flood, and Brisbane 2011 flood survivors 7-9 months post-flood (n=158). Findings indicated aftermath stress contributed to mental health outcomes over and above the contribution of perceived trauma, objective flood severity, prior mental health, self-efficacy and demographic factors. The implications of these results for the provision of community recovery services following natural disasters are discussed, including the need to provide effective targeting of support services throughout the lengthy rebuilding phase; a possible role for co-ordinating tradespeople; and training for insurance company staff aimed at minimising the incidence of insurance company staff inadvertently adding to disaster victims’ stress.

Modulating exercise-induced hormesis: Does less equal more?

Hormesis enco 16 mpasses the notion that low levels of stress stimulate or upregulate 17 existing cellular and molecular pathways that improve the capacity of cells and organisms to 18 withstand greater stress. This notion underlies much of what we know about how exercise 19 conditions the body and induces long-term adaptations. During exercise, the body is 20 exposed to various forms of stress, including thermal, metabolic, hypoxic, oxidative, and 21 mechanical stress. These stressors activate biochemical messengers, which in turn activate 22 various signaling pathways that regulate gene expression and adaptive responses. 23 Historically, antioxidant supplements, nonsteroidal anti-inflammatory drugs, and 24 cryotherapy have been favored to attenuate or counteract exercise-induced oxidative stress 25 and inflammation. However, reactive oxygen species and inflammatory mediators are key 26 signaling molecules in muscle, and such strategies may mitigate adaptations to exercise. 27 Conversely, withholding dietary carbohydrate and restricting muscle blood flow during 28 exercise may augment adaptations to exercise. In this review article, we combine, integrate, 29 and apply knowledge about the fundamental mechanisms of exercise adaptation. We also 30 critically evaluate the rationale for using interventions that target these mechanisms under 31 the overarching concept of hormesis. There is currently insufficient evidence to establish 32 whether these treatments exert dose-dependent effects on muscle adaptation. However, 33 there appears to be some dissociation between the biochemical/molecular effects and 34 functional/performance outcomes of some of these treatments. Although several of these 35 treatments influence common kinases, transcription factors and proteins, it remains to be 36 determined if these interventions complement or negate each other, and whether such 37 effects are strong enough to influence adaptations to exercise.