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31.
Few studies have investigated the presence of shift work disorder (SWD) in the general community. We addressed many of the limitations in this literature and present new findings. SWD has been treated as an ‘all or none’ construct but we propose the need to consider the ‘severity’ of the disorder. Using random digit dialling, we randomly recruited 1163 participants. Participants completed an extensive battery of scales and questions concerning work, health and individual differences. Three questions based on the criteria from the International Classification for Sleep Disorders were used to categorise participants with SWD (n = 176). In addition, we asked participants whether SWD interfered with aspects of their life and high ratings were used to define severe shift work disorder (SSWD). The prevalence of SWD was 32.1% among night workers and 10.1% in day workers (p<.001). SSWD was present in 9.1% of night workers and 1.3% of day workers (p<.001). Adjusted logistic regression analyses found significant associations between SWD and night work (OR  = 3.35, CI 2.19-5.12), weekly work hours (OR  = 1.02, CI 1.00–1.04), short sleep (≤6 h; OR  = 2.93, CI 1.94–4.41), languidity (OR  = 1.11, CI 1.06–1.16) and resilience (OR  = 0.56, CI 0.43–0.81). Night work, short sleep, languidity, and hypertension were significantly associated with SSWD. Overall, participants with SSWD slept 0.80 h less than other participants (p<.001). Night work, short sleep and languidity were associated with both SWD and SSWD. Day workers with SWD symptoms reported significantly shorter sleep duration, higher levels of languidity and worked longer working hours compared to day workers without SWD.  相似文献   
32.
Here we have characterized perthamide C, a cyclopeptide from a Solomon Lithistid sponge Theonella swinhoei, which displays an anti-inflammatory/immunomodulatory activity. The study has been performed using the carragenan-induced mouse paw edema that displays an early (0–6 h) and a late phase (24–96 h). Perthamide C significantly inhibits neutrophils infiltration in tissue both in the early and late phases. This effect was coupled to a reduced expression of the endothelial nitric oxide synthase (eNOS) in the early phase while cyclooxygenase-1 and 2 (COX-1, COX-2), and inducible NOS (iNOS) expression were unaffected. In the late phase perthamide C reduced expression of both NOS isoforms without affecting COXs expression. This peculiar selectivity toward the two enzymes deputed to produce NO lead us to investigate on a possible action of perthamide C on lymphocytes infiltration and activation. We found that perthamide C inhibited the proliferation of peripheral lymphocytes, and that this effect was secondary to its metabolic activation in vivo. Indeed, in vitro perthamide C did not inhibit proliferation as opposite to its metabolite perthamide H.In conclusion, perthamide C selectively interferes with NO generation triggered by either eNOS or iNOS without affecting either COX-1 or COX-2. This in turn leads to modulation of the inflammatory response through a reduction of vascular permeability, neutrophil infiltration as well as lymphocyte proliferation.  相似文献   
33.
Journal of Ethology - By gathering data on people during their ordinary daily activities, we tested if looking at, but not manipulating, smartphones led to a mimicry response in the observer....  相似文献   
34.
Nitroxide radicals are an emerging class of interesting compounds with versatile antioxidant and radioprotective properties. All literature studies have so far concentrated on compounds bearing only one nitroxide function. Here, we now investigate and compare the radical scavenging behaviour and antioxidant activity of aromatic indolinonic and aliphatic piperidine bis-nitroxides, i.e compounds bearing two nitroxide functions. Their corresponding mono-derivatives were also studied for comparison. Radical scavenging activity was investigated using EPR and UV–Vis spectroscopy by following spectral changes in acetonitrile of the nitroxides in the presence of alkyl and peroxyl radicals generated, respectively, under anoxic or aerobic conditions from thermal decomposition of AMVN [2,2′-azobis(2,4-di-methylvaleronitrile)]. Antioxidant activity of the nitroxides was evaluated by monitoring conjugated dienes (CD) formation during methyl linoleate micelles peroxidation and by measuring carbonyl content in oxidized bovine serum albumin (BSA). The results show that: (a) each nitroxide moiety in bis-nitroxides scavenges radicals independent of each other; (b) aliphatic nitroxides do not scavenge peroxyl radicals, at least under the experimental conditions used here, whereas indolinonic aromatic ones do: their stoichiometric number is 1.14 and 2.17, respectively, for mono- and bis-derivatives; (c) bis-nitroxides are roughly twice more efficient at inhibiting lipid peroxidation compared to their corresponding mono-derivatives. Although this study provides only comparative information on the relative radical-scavenging abilities of mono- and bis-nitroxides, it helps in understanding further the interesting reactivity of these compounds especially with regards to peroxyl radicals where many controversies in the literature exist.  相似文献   
35.
ABSTRACT

To understand the mechanisms which enable the nucleus to function under low water potential, the morphology and biochemistry of potato cell nuclei were studied. Conformational modifications were observed in the chromatin of nuclei of cells growing under low water potential. These modifications include a higher number of heterochromatic centres, enlargement of the nuclear diameter, and a different accessibility of DNA to the action of restriction enzymes. Biochemical analyses showed that these chromatin modifications may coincide with quantitative and qualitative variations of several nuclear proteins, some of which may belong to the dehydrin family. We especially focussed our attention on a 45-kDa protein that is heat-stable and is recognised by an antibody raised against the conserved domain of dehydrins. The survival of potato cells in an environment where water availability is low may depend on several simultaneous events regarding the nucleus. The accumulation in the nucleus of specific proteins such as dehydrins could be required to stabilise the chromatin by means of their molecule-salvation action. Further studies are in progress to check whether or not variations in chromatin organisation may be one of the numerous traits that a cell must acquire to become water-stress resistant.  相似文献   
36.
Campylobacter have emerged as the most common bacterial food-borne illness in the developed world. The ability to reduce Campylobacter infections in humans is linked to the full comprehension of the principal key aspects of its infection cycle. A microbial diagnostic microarray detecting Campylobacter housekeeping, structural, and virulence associated genes was designed and validated using genomic DNA from reference and field strains of Campylobacter jejuni and coli isolated from human, chicken, and raw milk. This microarray was confirmed to be a powerful diagnostic tool for monitoring emerging Campylobacter pathotypes as well as for epidemiological, environmental, and phylogenetic studies including the evaluation of genome plasticity.  相似文献   
37.

Introduction

Systemic sclerosis (SSc) is a connective tissue disorder characterized by endothelial cell injury, autoimmunity and fibrosis. The following three fibrillin-1 alterations have been reported in SSc. (1) Fibrillin-1 microfibrils are disorganized in SSc dermis. (2) Fibrillin-1 microfibrils produced by SSc fibroblasts are unstable. (3) Mutations in the FBN1 gene and anti-fibrillin-1 autoantibodies have been reported in SSc. Fibrillin-1 microfibrils, which are abundantly produced by blood and lymphatic microvascular endothelial cells (B-MVECs and Ly-MVECs, respectively), sequester in the extracellular matrix the latent form of the potent profibrotic cytokine transforming growth factor β (TGF-β). In the present study, we evaluated the effects of SSc sera on the deposition of fibrillin-1 and microfibril-associated glycoprotein 1 (MAGP-1) and the expression of focal adhesion molecules by dermal B-MVECs and Ly-MVECs.

Methods

Dermal B-MVECs and Ly-MVECs were challenged with sera from SSc patients who were treatment-naïve or under cyclophosphamide (CYC) treatment and with sera from healthy controls. Fibrillin-1/MAGP-1 synthesis and deposition and the expression of αvβ3 integrin/phosphorylated focal adhesion kinase and vinculin/actin were evaluated by immunofluorescence and quantified by morphometric analysis.

Results

Fibrillin-1 and MAGP-1 colocalized in all experimental conditions, forming a honeycomb pattern in B-MVECs and a dense mesh of short segments in Ly-MVECs. In B-MVECs, fibrillin-1/MAGP-1 production and αvβ3 integrin expression significantly decreased upon challenge with sera from naïve SSc patients compared with healthy controls. Upon challenge of B-MVECs with sera from CYC-treated SSc patients, fibrillin-1/MAGP-1 and αvβ3 integrin levels were comparable to those of cells treated with healthy sera. Ly-MVECs challenged with SSc sera did not differ from those treated with healthy control sera in the expression of any of the molecules assayed.

Conclusions

Because of the critical role of fibrillin-1 in sequestering the latent form of TGF-β in the extracellular matrix, its decreased deposition by B-MVECs challenged with SSc sera might contribute to dermal fibrosis. In SSc, CYC treatment might limit fibrosis through the maintenance of physiologic fibrillin-1 synthesis and deposition by B-MVECs.  相似文献   
38.
People with Down syndrome, a frequent genetic disorder in humans, have increased risk of health problems associated with this condition. One clinical feature of Down syndrome is the increased prevalence and severity of periodontal disease in comparison with the general population. Because saliva plays an important role in maintaining oral health, in the present study the salivary proteome of Down syndrome subjects was investigated to explore modifications with respect to healthy subjects. Whole saliva of 36 Down syndrome subjects, divided in the age groups 10–17 yr and 18–50 yr, was analyzed by a top-down proteomic approach, based on the high performance liquid chromatography-electrospray ionization–MS analysis of the intact proteins and peptides, and the qualitative and quantitative profiles were compared with sex- and age-matched control groups. The results showed the following interesting features: 1) as opposed to controls, in Down syndrome subjects the concentration of the major salivary proteins of gland origin did not increase with age; as a consequence concentration of acidic proline rich proteins and S cystatins were found significantly reduced in older Down syndrome subjects with respect to matched controls; 2) levels of the antimicrobial α-defensins 1 and 2 and histatins 3 and 5 were significantly increased in whole saliva of older Down syndrome subjects with respect to controls; 3) S100A7, S100A8, and S100A12 levels were significantly increased in whole saliva of Down syndrome subjects in comparison with controls. The increased level of S100A7 and S100A12 may be of particular interest as a biomarker of early onset Alzheimer''s disease, which is frequently associated with Down syndrome.Down syndrome (DS)1 is a frequent genetic disorder in humans characterized by premature aging (1). A clinical feature of people with DS is the increased prevalence and severity of periodontal disease compared with age-matched subjects of similar levels of intellectual impairment and compared with the general population (2). Common conditions observed in DS are marginal gingivitis, acute and subacute necrotizing gingivitis, advanced periodontitis, gingival recession, and pocket formation (3, 4). It is known that saliva plays an important role in maintaining oral and dental health, because of the presence of a variety of antimicrobial peptides mainly derived from gland secretion, oral epithelial cells, and neutrophils (5). Several papers reported that neutrophils and T-lymphocyte function is impaired in people with DS (69). However, the salivary secretion of the antimicrobial LL-37 in young individuals with DS was found normal (10). A review of the literature (11, 12) reveals only sporadic and contradictory reports that attempt to explain the role of saliva in the oral health of subjects with DS, and on the whole, information on the biochemical composition of their saliva is scarce. On the basis of the above information, in the present study, we proposed to investigate the salivary proteome of DS subjects by an intact protein-based “top-down” approach. The spectrum of salivary peptides of DS subjects was compared with that of sex and age-matched healthy control groups to determine qualitative and quantitative differences. Interestingly, the results showed that several members of the S100A family, which possess different biological functions, and also described as potential markers of the Alzheimer Disease, were significantly increased in saliva of Down syndrome subjects with respect to controls.  相似文献   
39.
Bladder cancer is the fourth most common cause of cancer in males in the United States. Invasive behavior is a major determinant of prognosis. In this study, we identified mammalian target of rapamycin complex 2 (mTORC2) as a central regulator of bladder cancer cell migration and invasion. mTORC2 activity was assessed by the extent of phosphorylation of Ser473 in AKT and determined to be approximately 5-fold higher in specimens of invasive human bladder cancer as opposed to non-invasive human bladder cancer. The immortalized malignant bladder cell lines, UMUC-3, J82 and T24 demonstrated higher baseline mTORC2 activity relative to the benign bladder papilloma-derived cell line RT4 and the normal urothelial cell line HU1. The malignant bladder cancer cells also demonstrated increased migration in transwell and denudation assays, increased invasion of matrigel, and increased capacity to invade human bladder specimens. Gene silencing of rictor, a critical component of mTORC2, substantially inhibited bladder cancer cell migration and invasion. This was accompanied by a significant decrease in Rac1 activation and paxillin phosphorylation. These studies identify mTORC2 as a major target for neutralizing bladder cancer invasion.  相似文献   
40.
Superparamagnetic iron oxide (SPIO) and ultra small superparamagnetic iron oxide (USPIO) nanoparticles have been developed as magnetic resonance imaging (MRI) contrast agents. Iron oxide nanoparticles, that become superparamagnetic if the core particle diameter is ~ 30nm or less, present R1 and R2 relaxivities which are much higher than those of conventional paramagnetic gadolinium chelates. Generally, these magnetic particles are coated with biocompatible polymers that prevent the agglomeration of the colloidal suspension and improve their blood distribution profile. In spite of their potential as MRI blood contrast agents, the biomedical application of iron oxide nanoparticles is still limited because of their intravascular half-life of only few hours; such nanoparticles are rapidly cleared from the bloodstream by macrophages of the reticulo-endothelial system (RES). To increase the life span of these MRI contrast agents in the bloodstream we proposed the encapsulation of SPIO nanoparticles in red blood cells (RBCs) through the transient opening of cell membrane pores. We have recently reported results obtained by applying our loading procedure to several SPIO nanoparticles with different chemical physical characteristics such as size and coating agent. In the current investigation we showed that the life span of iron-based contrast agents in the mice bloodstream was prolonged to 12 days after the intravenous injection of murine SPIO-loaded RBCs. Furthermore, we developed an animal model that implicates the pretreatment of animals with clodronate to induce a transient suppression of tissue macrophages, followed by the injection of human SPIO-loaded RBCs which make it possible to encapsulate nanoparticle concentrations (5.3-16.7mM Fe) higher than murine SPIO-loaded RBCs (1.4-3.55mM Fe). The data showed that, when human RBCs are used as more capable SPIO nanoparticle containers combined with a depletion of tissue macrophages, Fe concentration in animal blood is 2-3 times higher than iron concentration obtained by the use of murine SPIO-loaded RBCs.  相似文献   
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