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951.
Abstract

Background

Cognitive and affective job insecurity are compared in six aspects related to employment: job loss, worsening of tasks, schedule, salary and workplace, and difficulties over finding an alternative job (also known as labor market insecurity). Methods: Cross-sectional study. Data comes from the third Spanish Psychosocial Risks Survey (2016) which is a representative sample of the Spanish salaried population. Results: Affective responses are more variable than cognitive ones resulting in a low degree of answer concordance (IC95% Kappa = 0.08–0.13 to 0.18–0.23). There is a significant percentage of workers (22.5–50.3%) highly concerned about their future despite perceiving low probabilities of experiencing the specific insecurity threat, except for the labor market insecurity question. Conclusion: The differences observed in the degree of insecurity between the affective and the cognitive forms confirm that they are measuring different components of the insecurity construct. These differences are partly due to the economic situation of their households.  相似文献   
952.
Dengue is the most important mosquito-borne viral infection in humans. Recent evidence suggests that vitamin D influences virus replication. In this work, the effect of vitamin D treatment on dengue virus infection in human hepatic Huh-7 cells and on virus infection and cytokine production in the human monocytic U937 cells was evaluated. Exposure to 1α,25-dihydroxy-vitamin D3, resulted in a significant reduction in the number of infected cells, in conditions where cell viability was not affected. Viral replication in monocytic cells was more susceptible to vitamin D3 than replication in the hepatic cells. Moreover, vitamin D3 significantly reduced the levels of proinflammatory cytokines (TNF-α, IL-6, IL-12p70 and IL-1β) produced by infected U937 cells. These results suggest that vitamin D3 may represent a potentially useful antiviral compound.  相似文献   
953.
954.
Farnesyltransferase (FTase) is one of the prenyltransferase family enzymes that catalyse the transfer of 15-membered isoprenoid (farnesyl) moiety to the cysteine of CAAX motif-containing proteins including Rho and Ras family of G proteins. Inhibitors of FTase act as drugs for cancer, malaria, progeria and other diseases. In the present investigation, we have developed two structure-based pharmacophore models from protein–ligand complex (3E33 and 3E37) obtained from the protein data bank. Molecular dynamics (MD) simulations were performed on the complexes, and different conformers of the same complex were generated. These conformers were undergone protein–ligand interaction fingerprint (PLIF) analysis, and the fingerprint bits have been used for structure-based pharmacophore model development. The PLIF results showed that Lys164, Tyr166, TrpB106 and TyrB361 are the major interacting residues in both the complexes. The RMSD and RMSF analyses on the MD-simulated systems showed that the absence of FPP in the complex 3E37 has significant effect in the conformational changes of the ligands. During this conformational change, some interactions between the protein and the ligands are lost, but regained after some simulations (after 2 ns). The structure-based pharmacophore models showed that the hydrophobic and acceptor contours are predominantly present in the models. The pharmacophore models were validated using reference compounds, which significantly identified as HITs with smaller RMSD values. The developed structure-based pharmacophore models are significant, and the methodology used in this study is novel from the existing methods (the original X-ray crystallographic coordination of the ligands is used for the model building). In our study, along with the original coordination of the ligand, different conformers of the same complex (protein–ligand) are used. It concluded that the developed methodology is significant for the virtual screening of novel molecules on different targets.  相似文献   
955.
Hypotensive effects of oral sodium nitrite have been reported as alternative sources of nitric oxide (NO) formation in animals and human beings. Reductions in NO bioavailability were observed in lead‐induced hypertension. However, no previous study has examined whether a single daily dose of sodium nitrite prevents the reductions in the NO bioavailability in lead‐induced hypertension. Then, we expanded previous reports and evaluated the effects of sodium nitrite in 7‐day lead‐treated rats. Wistar rats were divided into four experimental groups: Pb+sodium nitrite group received intraperitoneally (i.p.) 1st dose 8 µg/100 g of lead acetate and a subsequent dose of 0.1 µg/100 g, and daily treatment with sodium nitrite (45 mg/kg/day) or water (Pb group) by gavage for 7 days; Sodium nitrite group received i.p. 1st dose 8 µg/100 g of sodium acetate and a subsequent dose of 0.1 µg/100 g, and daily treatment with sodium nitrite (45 mg/kg/day) or water (saline group) by gavage for 7 days. Similar and higher whole‐blood lead levels (11.5 ± 1.2 and 13.2 ± 0.7 µg/dL) were found in lead‐exposed rats treated with either water or sodium nitrite (Pb or Pb+sodium nitrite, respectively; both p < 0.05 versus control groups). We found lower NO markers such as plasma nitrite and nitrite + nitrate (NOx) levels (both p < 0.05 versus controls) in lead‐exposed rats compared with normotensive (sodium acetate)‐treated controls (Pb group versus saline group; p < 0.05). Lead induced increases in systolic blood pressure (from 130 ± 2 to 164 ± 6 mmHg in Pb group; p < 0.05); however, both lead‐induced decreases in NO markers and hypertension (Pb+sodium nitrite group versus Pb group; both p < 0.05) were prevented by a single daily dose of sodium nitrite. In conclusion, these findings are consistent with the idea that impaired NO bioavailability contributes to the maintenance of elevated blood pressure in lead‐induced hypertension. Additionally, our results show that sodium nitrite exerts antihypertensive effects in lead‐induced hypertension and provide evidence that sodium nitrite prevents the impairment of NO, thus, reaffirming the relevance of nitrite as alternative source of recycling back to NO.  相似文献   
956.
957.
958.
We report herein the design, synthesis, and biological screening of a series of 15 disulfide prodrugs as precursors of albitiazolium bromide (T3/SAR97276, compound 1), a choline analogue which is currently being evaluated in clinical trials (phase II) for severe malaria. The corresponding prodrugs are expected to revert back to the active bis-thiazolium salt through an enzymatic reduction of the disulfide bond. To enhance aqueous solubility of these prodrugs, an amino acid residue (valine or lysine) or a phosphate group was introduced on the thiazolium side chain. Most of the novel derivatives exhibited potent in vitro antimalarial activity against P. falciparum. After oral administration, the cyclic disulfide prodrug 8 showed the best improvement of oral efficacy in comparison to the parent drug.  相似文献   
959.
Stroke and myocardial infarction are leading causes of death and disability worldwide. Typically, these events are triggered by the rupture or erosion of "vulnerable" atherosclerotic plaque, a phenomenon termed atherothrombosis.Three platelet activation pathways are presumed to be particularly important in the genesis of atherothrombosis and are triggered by 1) cyclo-oxygenase (COX)-1 mediated thromboxane A2 (TXA2) synthesis and activation via the TXA2 receptor, 2) adenosine diphosphate (ADP) via the P2Y12 receptor, and 3) thrombin via the protease activated receptor (PAR)-1.Despite the efficacy of aspirin and of a growing family of P2Y12 receptor antagonists on the first 2 pathways, major cardiovascular events continue to occur in patients with coronary and cerebrovascular disease, suggesting that thrombin-mediated platelet activation may contribute to these adverse events.Recently, a novel class of antiplatelet agents able to inhibit thrombin-mediated platelet activation has been developed, PAR-1 inhibitors. In this chapter, we will discuss the rationale underlying the development of this novel class of agents focus on the two drugs in the most advanced stages of development: vorapaxar (SCH530348) and atopaxar (E5555).  相似文献   
960.
Epidemiological and dietary studies show that nutritional deficit of omega-3 polyunsaturated fatty acids (ω-3 PUFA) is directly related to the prevalence and severity of depression. Supplementation with docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) during critical periods of development (pregnancy and lactation) is essential for cortical maturation, synaptogenesis and myelination, and may also mitigate the risk for cognitive deficits and psychopathologies in young adults. The present study was performed to evaluate the involvement of serotonin (5-HT) receptors, particularly of 5-HT(1A), and hippocampal brain-derived neurotrophic factor (BDNF) expression in the antidepressant effect of ω-3 PUFA supplementation. In Experiment 1, the antidepressant effects of fish oil were assessed by the modified forced swim test in adult rats. The data indicated a robust antidepressant effect produced by this supplementation and that treatment of the rats with WAY 100135 reversed this effect. In Experiment 2, cortical and hippocampal contents of BDNF, 5-HT, dopamine (DA) and its metabolites, 5-hydroxyindoleacetic acid (5-HIAA), and 3,4-dihydroxyphenylacetic acid (DOPAC), were determined in animals subjected to the same protocol. Increased BDNF expression in the cortex and hippocampus of both age groups was detected. In 90 day-old rats, 5-HT content in the hippocampus was increased, whereas 5-HIAA formation was diminished in the fish oil group. We suggest the occurrence of a reciprocal involvement of 5-HT(1A) receptors activation and the hippocampal BDNF-increased expression mediated by fish oil supplementation. These data corroborate and expand the notion that supplementation with ω-3 PUFA produces antidepressant effects mediated by an increase in serotonergic neurotransmission, particularly in the hippocampus. This article is part of a Special Issue entitled 'Anxiety and Depression'.  相似文献   
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