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Cell of Escherichia coli B, Thiobacillus intermedius 13-1, Bacillus amyloliquefaciens IFO14141, Staphylococcus aureus IID975, and Saccharomyces cerevisiae Kyokai no. 7 cultivated in nutrient media were subjected to hypergraviation...
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Cell of Escherichia coli B, Thiobacillus intermedius 13-1, Bacillus amyloliquefaciens IFO14141, Staphylococcus aureus IID975, and Saccharomyces cerevisiae Kyokai no. 7 cultivated in nutrient media were subjected to hypergraviationla stress for a period of between 1 and 24 h at 450,000 * g. The E. coli. B. amyloliquefaciens and S. cerevisiae cells showed survival rates of 38.5%, 0.005%, and 14.7%, respectively, after gravity treatment for 24 h as determined by their ability for colony formation, whereas a survival rate of S. cerevisiae cells of almost 100% was observed as determined using the methylene blue reduction test. E. coli cells, either in the logarithmic growth phase or cultivated in minimum media, were more sensitive to gravitational stress that those either in the stationary phase or cultivated in nutrient media.
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In this article, we argued that the term stress has served as a valuable heuristic, helping researchers to integrate traditions that illuminate different stages of the process linking stressful life events to disease. We provided ...
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In this article, we argued that the term stress has served as a valuable heuristic, helping researchers to integrate traditions that illuminate different stages of the process linking stressful life events to disease. We provided a short history of three traditions in the study of stress: the epidemiological, psychological, and biological. The epidemiological tradition focuses on defining which circumstances and experiences are deemed stressful on the basis of consensual agreement that they constitute threats to social or physical well-being. The psychological tradition focuses on individuals' perceptions of the stress presented by life events on the basis of their appraisals of the threats posed and the availability of effective coping resources. The biological tradition focuses on brain-based perturbations of physiological systems that are otherwise essential for normal homeostatic regulation and metabolic control. The foci of these three traditions have informed elements of a stage model of disease, wherein events appraised as stressful are viewed as triggering affective states that in turn engender behavioral and biological responses having possible downstream implications for disease.
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Biodegradable elastic poly(L-lactide-co-epsilon-caprolactone) (PLCL) (50:50) copolymer was blended with collagen (0.05, 0.1 and 0.2% w/w) in an acidic dioxane solution to form a collagen/PLCL hybrid material suitable for tissue en...
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Biodegradable elastic poly(L-lactide-co-epsilon-caprolactone) (PLCL) (50:50) copolymer was blended with collagen (0.05, 0.1 and 0.2% w/w) in an acidic dioxane solution to form a collagen/PLCL hybrid material suitable for tissue engineering applications. Stability and dispersivity of collagen on collagen/PLCL hybrid films and collagen coated PLCL films under mechanical stress were determined by a collagen release test and water contact angle measurement. Hybrid films had a higher stability than collagen-coated PLCL films. Elastic recovery as well as high interconnectivity and uniform pore morphology of the hybrid scaffolds were not affected by the collagen concentration. Fibroblasts (NIH-3T3) cell culture test was performed for cell growth and viability evaluation. Collagen concentration had little affect on the initial cell adhesion after 4 h cell culture; but after 48 h cell culture, increased cell proliferation on the hybrid films was observed. The hybrid material can be applied as a scaffold for vessel and cartilage regeneration for mechano-active tissue engineering.
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Additional spatial nonuniform magnetic anisotropy is induced in the basal plane of a FeBO3 single crystal using low-symmetry mechanical stresses. The effect of the nonuniform magnetic anisotropy on the magnetic state of this weak ...
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Additional spatial nonuniform magnetic anisotropy is induced in the basal plane of a FeBO3 single crystal using low-symmetry mechanical stresses. The effect of the nonuniform magnetic anisotropy on the magnetic state of this weak easy-plane ferromagnet is studied by a magnetooptic method. When the nonuniformly stressed FeBO3 crystal is magnetized in the basal plane near a certain preferential direction, the crystal is found to transform from a homogeneous into a spatially modulated magnetic state, which can be represented by a static spin wave in which a local ferromagnetism vector lies in the basal plane and oscillates about the average magnetization direction in the crystal.
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Abstract Identification of genes playing a role in stress tolerance has great importance in the elucidation of biotic and abiotic plant stress pathways. In this study, comparative analysis was carried out for genes (bZIP60 and bZI...
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Abstract Identification of genes playing a role in stress tolerance has great importance in the elucidation of biotic and abiotic plant stress pathways. In this study, comparative analysis was carried out for genes (bZIP60 and bZIP28) activated during ER stress response in plant root and leaf tissues. The relative water content (RWC) of the plant leaves grown under stress factors, di-thio-threitol (DTT) and polyethylene glycol (PEG) were measured at critical periods. Expression analysis of bZIP60 and bZIP28 genes involved at ER stress pathways was evaluated through RT-PCR assay at determined intervals of time, (in Nimet cultivar of alfalfa) under the artificial ER stress implemented by DTT and drought stress by PEG. According to the results, it was determined that DTT reduced the functionality of these two genes involved in ER stress pathways. The most critical time for plants in drought (PEG) tolerance was 8th h after treatment, in which the expression of bZIP60 in leaves was increased compared to other applications (about 42 times). Furthermore, according to the findings, the two studied gene regions, bZIP60 have a more active role in the stress pathways than bZIP28; and the leaf tissues were more affected than the root tissues under the stress conditions.
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The possibility that immunological changes might contribute to symptom severity in fibromyalgia (FM) prompted this proof-of-concept study to determine whether differences in monocyte subpopulations might be present in persons with...
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The possibility that immunological changes might contribute to symptom severity in fibromyalgia (FM) prompted this proof-of-concept study to determine whether differences in monocyte subpopulations might be present in persons with FM compared with healthy controls. Relationships were assessed by comparing specific symptoms in those with FM (n=20) and patterns of monocyte subpopulations with healthy age-matched and gender-matched controls (n=20). Within the same time frame, all participants provided a blood sample and completed measures related to pain, fatigue, sleep disturbances, perceived stress, positive and negative affect and depressed mood (and the Fibromyalgia Impact Questionnaire for those with FM). Monocyte subpopulations were assessed using flow cytometry. No differences were observed in total percentages of circulating monocytes between the groups; however, pain was inversely correlated with percentages of circulating classical (r=-0.568, p=0.011) and intermediate (r=-0.511, p=0.025) monocytes in the FM group. Stress and pain were highly correlated (r=0.608, p=0.004) in the FM group. The emerging pattern of changes in the percentages of circulating monocyte subpopulations concomitant with higher ratings of perceived pain and the correlation between stress and pain found in the FM group warrant further investigation. Copyright (C) 2015 John Wiley & Sons, Ltd.
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Functional aspects of the concept on the multi-level continuum of neuroplasticity and neuropathology is discussed. The harmony and pleiotropicity of the multifaceted mechanisms at molecular, synaptic, cellular, and network levels ...
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Functional aspects of the concept on the multi-level continuum of neuroplasticity and neuropathology is discussed. The harmony and pleiotropicity of the multifaceted mechanisms at molecular, synaptic, cellular, and network levels is associated with a high adaptive plasticity of brain regions involved in its controlling and integrative functions in the organism. Brain regions involved in cognitive functions and emotions (e.g. the lymbic system, particularly the hippocampus) possess high plasticity potential, however, the price of high plasticity is selective vulnerability of these structures to pathological alterations induced by stress factors. Depending on the pathology, neuroplasticity can be reduced (as a result of neuronal death and neurogenesis disturbances as it happens in neurodegenerative diseases) or increased (e.g. during epileptogenesis when aberrant plasticity develops). Alongside with its fundamental significance for understanding processes in normal and pathological brain, the neuroplasticity continuum concept is practically important since it allows to evaluate the rationale for interfering in specific molecular processes involved in both normal adaptive plasticity and brain disease pathogenesis.
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The present study is a first attempt at evaluating the effects of repeated disturbance, such as that caused by mechanical fishing systems, on the target species, Tapes philippinarum, intensively exploited in the Lagoon of Venice (...
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The present study is a first attempt at evaluating the effects of repeated disturbance, such as that caused by mechanical fishing systems, on the target species, Tapes philippinarum, intensively exploited in the Lagoon of Venice (North-East Italy). In particular, in free-access fishing grounds, detrimental effects of dredging may be suffered by under-sized clams, which are disturbed by fishing tools many times throughout their lives before they are collected. Similar mechanical stress conditions are experienced by T. philippinarum in licensed areas, where they are farmed in aquaculture conditions and undergo the harmful impact of hydraulic dredging. To evaluate the effects of short-term mechanical stress, under-sized clams were subjected to experimental shaking in the laboratory, and detrimental effects on their well-being were investigated by applying the biomarker approach. Changes in physiological, biochemical and behavioural responses were evaluated by determining scope for growth, adenylate energy charge, survival in air time, reburrowing time, and shell damage level. Responses highlighted general worsening in clam condition as mechanical stress increased. Among the various measurements, survival in air and reburrowing time appeared particularly suitable as indices, their responsiveness and applicability suggesting their use in assessing mechanical stress due to dredging in field conditions.
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Differentiation is the process by which a cell activates the expression of tissue-specific genes, downregulates the expression of potency markers, and acquires the phenotypic characteristics of its mature fate. The signals that re...
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Differentiation is the process by which a cell activates the expression of tissue-specific genes, downregulates the expression of potency markers, and acquires the phenotypic characteristics of its mature fate. The signals that regulate differentiation include biochemical and mechanical factors within the surrounding microenvironment. We describe recent breakthroughs in our understanding of the mechanical control mechanisms that regulate differentiation, with a specific emphasis on the differentiation events that build the early mouse embryo. Engineering approaches to reproducibly mimic the mechanical regulation of differentiation will permit new insights into early development and applications in regenerative medicine.Expected final online publication date for the Annual Review of Biomedical Engineering, Volume 24 is June 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Arabidopsis basic leucine zipper transcription factor VIRE 2‐interacting protein 1 ( VIP 1) changes its localization from the cytosol to the nucleus when cells are subjected to mechanical or hypo‐osmotic stress, although the mec...
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Arabidopsis basic leucine zipper transcription factor VIRE 2‐interacting protein 1 ( VIP 1) changes its localization from the cytosol to the nucleus when cells are subjected to mechanical or hypo‐osmotic stress, although the mechanism of this change is not known. In this study, we show that change in VIP 1 subcellular localization is synchronized with a change in the VIP 1 phosphorylation state that is induced by mechanical/hypo‐osmotic stress. VIP 1 has three phosphorylatable serine residues in HXRXXS motifs, which are 14‐3‐3‐binding targets. Mutations of these residues results in the lack of 14‐3‐3 binding and prevents cytosolic localization of VIP 1. These results suggest that dephosphorylation of VIP 1 resulting from mechanical or hypo‐osmotic stress induces nuclear localization via 14‐3‐3 dissociation.
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