Abstract: Cortisol is important to our immune system, regulates our stress response, and is a factor in maintaining brain temperature. Saliva cortisol is a practical and useful non-invasive measurement that signifies the presence of the important hormone. Electrical activity in the jaw muscles typically rises when the muscles are moved during yawning and the electrical level is found to be correlated with the cortisol level. In two studies using identical paradigms, a total of 108 healthy subjects were exposed to yawning-provoking stimuli so that their cortisol levels and electrical nerve impulses from their jaw muscles was recorded. Electrical activity is highly correlated with cortisol levels in healthy people. The Hospital Anxiety and Depression Scale, Yawning Susceptibility Scale, General Health Questionnaire, demographic, health details were collected and exclusion criteria applied for voluntary recruitment: chronic fatigue, diabetes, fibromyalgia, heart condition, high blood pressure, hormone replacement therapy, multiple sclerosis, and stroke. Significant differences were found between the saliva cortisol samples for the yawners as compared with the non-yawners between rest and post-stimuli. Significant evidence supports the Thompson Cortisol Hypothesis that suggests rises in cortisol levels are associated with yawning. Ethics approval granted and professional code of conduct, confidentiality, and safety issues are approved therein.
Abstract: The aim of the current study was to develop and
validate a Response to Stressful Situations Scale (RSSS) for the
Portuguese population. This scale assesses the degree of stress
experienced in scenarios that can constitute positive, negative and
more neutral stressors, and also describes the physiological,
emotional and behavioral reactions to those events according to their
intensity. These scenarios include typical stressor scenarios relevant
to patients with schizophrenia, which are currently absent from most
scales, assessing specific risks that these stressors may bring on
subjects, which may prove useful in non-clinical and clinical
populations (i.e. Patients with mood or anxiety disorders,
schizophrenia). Results from Principal Components Analysis and
Confirmatory Factor Analysis of two adult samples from general
population allowed to confirm a three-factor model with good fit
indices: χ2 (144)= 370.211, p = 0.000; GFI = 0.928; CFI = 0.927; TLI =
0.914, RMSEA = 0.055, P(rmsea ≤0.005) = .096; PCFI = .781.
Further data analysis of the scale revealed that RSSS is an adequate
assessment tool of stress response in adults to be used in further
research and clinical settings, with good psychometric characteristics,
adequate divergent and convergent validity, good temporal stability
and high internal consistency.
Abstract: In Arabidopsis, several genes encoding proteins with ankyrin repeats and transmembrane domains (AtANKTM) have been identified as mediators of biotic and abiotic stress responses. It has been known that the expression of an AtANKTM gene, At2g24600, is induced in response to abiotic stress and that there are four splicing variants derived from this locus. In this study, by RT-PCR and sequencing analysis, an unknown splicing variant of the At2g24600 transcript was identified. Based on differences in the predicted amino acid sequences, the five splicing variants are divided into three groups. The three predicted proteins are highly homologous, yet have different numbers of ankyrinrepeats and transmembrane domains. It is generally considered that ankyrin repeats mediate protein-protein interaction and that the number oftransmembrane domains affects membrane topology of proteins. The protein variants derived from the At2g24600 locus may have different molecular functions each other.
Abstract: MicroRNAs (miRNAs), a class of approximately 22 nucleotide long non coding RNAs which play critical role in different biological processes. The mature microRNA is usually 19–27 nucleotides long and is derived from a bigger precursor that folds into a flawed stem-loop structure. Mature micro RNAs are involved in many cellular processes that encompass development, proliferation, stress response, apoptosis, and fat metabolism by gene regulation. Resent finding reveals that certain viruses encode their own miRNA that processed by cellular RNAi machinery. In recent research indicate that cellular microRNA can target the genetic material of invading viruses. Cellular microRNA can be used in the virus life cycle; either to up regulate or down regulate viral gene expression Computational tools use in miRNA target prediction has been changing drastically in recent years. Many of the methods have been made available on the web and can be used by experimental researcher and scientist without expert knowledge of bioinformatics. With the development and ease of use of genomic technologies and computational tools in the field of microRNA biology has superior tremendously over the previous decade. This review attempts to give an overview over the genome wide approaches that have allow for the discovery of new miRNAs and development of new miRNA target prediction tools and databases.
Abstract: This research was undertaken to study enzymatic activity in the shoots, roots, and rhizosphere of alfalfa (Medicago sativa L.) grown in quartz sand that was uncontaminated and
contaminated with phenanthrene at concentrations of 10 and 100 mg kg-1. The higher concentration of phehanthrene had a distinct
phytotoxic effect on alfalfa, inhibiting seed germination energy, plant survival, and biomass accumulation. The plant stress response to the
environmental pollution was an increase in peroxidase activity. Peroxidases were the predominant enzymes in the alfalfa shoots and
roots. The peroxidase profile in the shoots differed from that in the roots and had different isoenzyme numbers. 2,2'-Azinobis-(3-ethylbenzo-thiazoline-6-sulphonate) (ABTS) peroxidase was
predominant in the shoots, and 2,7-diaminofluorene (2,2-DAF)
peroxidase was predominant in the roots. Under the influence of
phenanthrene, the activity of 2,7-DAF peroxidase increased in the
shoots, and the activity of ABTS peroxidase increased in the roots.
Alfalfa root peroxidases were the prevalent enzyme systems in the
rhizosphere sand. Examination of the activity of alfalfa root
peroxidase toward phenanthrene revealed the possibility of
involvement of the plant enzyme in rhizosphere degradation of the
PAH.
Abstract: This study sought to uncover the complex role of
stress in the workplace by investigating both positive (eustress) and
negative (distress) stress responses. In particular, the study tested a
mediation model in which organisational stressors (person-job fit and
role overload) influence employee affective wellbeing, both directly
and indirectly through stress responses. Participants were recruited
from retail and finance organisations in Australia and New Zealand,
and asked to complete an anonymous online questionnaire. A total of
140 individuals returned completed questionnaires. The results show
that person-job fit influenced eustress, which in turn had a positive
effect on employee affective wellbeing; and role overload impacted
distress, which in turn held a negative influence on affective
wellbeing. These findings indicate that different organisational
stressors have unique relationships with eustress and distress
responses. Limitations and implications of the study are discussed.
Abstract: Bacterial molecular chaperone DnaK plays an essential role in protein folding, stress response and transmembrane targeting of proteins. DnaKs from many bacterial species, including Escherichia coli, Salmonella typhimurium and Haemophilus infleunzae are the molecular targets for the insect-derived antimicrobial peptide pyrrhocoricin. Pyrrhocoricin-like peptides bind in the substrate recognition tunnel. Despite the high degree of crossspecies sequence conservation in the substrate-binding tunnel, some bacteria are not sensitive to pyrrhocoricin. This work addresses the molecular mechanism of resistance of Helicobacter pylori DnaK to pyrrhocoricin. Homology modelling, structural and sequence analysis identify a single aminoacid substitution at the interface between the lid and the β-sandwich subdomains of the DnaK substrate-binding domain as the major determinant for its resistance.
Abstract: Brassinosteroids (BRs) regulate cell elongation,
vascular differentiation, senescence, and stress responses. BRs signal
through the BES1/BZR1 family of transcription factors, which
regulate hundreds of target genes involved in this pathway. In this
research a comprehensive genome-wide analysis was carried out in
BES1/BZR1 gene family in Arabidopsis thaliana, Cucumis sativus,
Vitis vinifera, Glycin max and Brachypodium distachyon.
Specifications of the desired sequences, dot plot and hydropathy plot
were analyzed in the protein and genome sequences of five plant
species. The maximum amino acid length was attributed to protein
sequence Brdic3g with 374aa and the minimum amino acid length
was attributed to protein sequence Gm7g with 163aa. The maximum
Instability index was attributed to protein sequence AT1G19350
equal with 79.99 and the minimum Instability index was attributed to
protein sequence Gm5g equal with 33.22. Aliphatic index of these
protein sequences ranged from 47.82 to 78.79 in Arabidopsis
thaliana, 49.91 to 57.50 in Vitis vinifera, 55.09 to 82.43 in Glycin
max, 54.09 to 54.28 in Brachypodium distachyon 55.36 to 56.83 in
Cucumis sativus. Overall, data obtained from our investigation
contributes a better understanding of the complexity of the
BES1/BZR1 gene family and provides the first step towards directing
future experimental designs to perform systematic analysis of the
functions of the BES1/BZR1 gene family.
Abstract: Application of pesticides in the paddy fields has
deleterious effects on non-target organisms including cyanobacteria
which are photosynthesizing and nitrogen fixing micro-organisms
contributing significantly towards soil fertility and crop yield.
Pesticide contamination in the paddy fields has manifested into a
serious global environmental concern. To study the effect of one such
pesticide, three cyanobacterial strains; Anabaena fertilissima,
Aulosira fertilissima and Westiellopsis prolifica were selected for
their stress responses to an Organochlorine insecticide - 6, 7, 8, 9, 10,
10-hexachloro-1, 5, 5a, 6, 9, 9a-hexahydro-6, 9-methano-2, 4, 3-
benzodioxathiepine-3-oxide, with reference to their photosynthesic
pigments-chlorophyll-a and carotenoids as well as accessory
pigments-phycobiliproteins (phycocyanin, allophycocyanin and
phycoerythrin), stress induced biochemical metabolites like
carbohydrates, proteins, amino acids, phenols and enzymes-nitrate
reductase, glutamine synthetase and succinate dehydrogenase. All
the three cyanobacterial strains were adversely affected by the
insecticide doses and inhibition was dose dependent. Reduction in
photosynthetic and accessory pigments, metabolites, nitrogen fixing
and respiratory enzymes of the test organisms were accompanied
with an initial increase in their total protein at lower Organochlorine
doses. On the other hand, increased amount of phenols in all the
insecticide treated concentrations was indicative of stressed activities
of the organisms.