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1.

Background  

Excess body fat is a major risk factor for disease primarily due to its endocrine activity. In recent years several criteria have been introduced to evaluate this factor. Nevertheless, treatment need is currently assessed only on the basis of an individual's Body Mass Index (BMI), calculated as body weight (in kg) divided by height in m2. The aim of our study was to determine whether application of the BMI, compared to adiposity-based criteria, results in underestimation of the number of subjects needing lifestyle intervention.  相似文献   
2.
The bidirectional relation between life events and self-reported depression was examined across a 1-year period. With Time 1 depression controlled, Time 2 stress accounted for an additional 10% of Time 2 depressive symptoms. Health-related stress, family violence, and financial stress at Time 2 predicted Time 2 depression after control for Time 1 depression. With Time 1 stress controlled, Time 2 depression accounted for 8% of the variance in Time 2 stress. Time 2 depression predicted Time 2 health-related stress, financial stress, household changes, spouse–partner stress, family violence stress, and substance abuse stress, controlling for each of these stressors at Time 1. The results describe a complex relation between stress and depression and suggest that the relation between stress and depression is moderated by the type of stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
This study examined differences in self-reported psychiatric symptomatology on the Minnesota Multiphasic Personality Inventory-2 according to adult attachment status on the Adult Attachment Interview in first-time mothers from a high-risk poverty sample. Participants reported fairly high levels of symptomatology regardless of attachment status. The dismissing adult attachment group reported comparatively little psychiatric distress, emphasized independence, and scored the lowest on self-reported anxiety. The preoccupied group was highest on a range of indices of psychiatric symptoms indicative of self-perceived distress and relationship problems. The autonomous group's scores ranged between the scores of the other 2 groups on most scales. These different symptom patterns are consistent with adult attachment status as an index of self-representation and as a set of strategies for processing emotions and thoughts related to distress and to attachment relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
UV radiation (UV) is classified as a “complete carcinogen” because it is both a mutagen and a non-specific damaging agent and has properties of both a tumor initiator and a tumor promoter. In environmental abundance, UV is the most important modifiable risk factor for skin cancer and many other environmentally-influenced skin disorders. However, UV also benefits human health by mediating natural synthesis of vitamin D and endorphins in the skin, therefore UV has complex and mixed effects on human health. Nonetheless, excessive exposure to UV carries profound health risks, including atrophy, pigmentary changes, wrinkling and malignancy. UV is epidemiologically and molecularly linked to the three most common types of skin cancer, basal cell carcinoma, squamous cell carcinoma and malignant melanoma, which together affect more than a million Americans annually. Genetic factors also influence risk of UV-mediated skin disease. Polymorphisms of the melanocortin 1 receptor (MC1R) gene, in particular, correlate with fairness of skin, UV sensitivity, and enhanced cancer risk. We are interested in developing UV-protective approaches based on a detailed understanding of molecular events that occur after UV exposure, focusing particularly on epidermal melanization and the role of the MC1R in genome maintenance.  相似文献   
5.
The zinc(II) triflate‐catalyzed synthesis of highly functionalized pyrroles is described. The sequence involves the preliminary preparation of α‐aminohydrazones by Michael addition of primary amines to 1,2‐diaza‐1,3‐dienes. The treatment of these intermediates with dialkyl acetylenedicarboxylates produces α‐(N‐enamino)‐hydrazones that are converted into the corresponding pyrroles. The substituents on the carbon in position four of 1,2‐diaza‐1,3‐dienes drive the regioselectivity of the ring closure process. Starting from 4‐aminocarbonyl‐1,2‐diaza‐1,3‐dienes only dialkyl 1‐substituted 5‐aminocarbonyl‐1H‐pyrrole‐2,3‐dicarboxylates are achieved by Lewis acid‐catalyzed ring closure. A screening of several Lewis/Brønsted acid catalysts is performed. Zinc(II) triflate is the most efficient catalyst. Under similar reaction conditions, employing 4‐alkoxycarbonyl‐1,2‐diaza‐1,3‐dienes, only 4‐hydroxy‐1H‐pyrrole‐2,3‐dicarboxylates are synthesized. These latter reactions can be accomplished regioselectively also in one pot. Using 4‐aminocarbonyl‐1,2‐diaza‐1,3‐dienes, diamines and dialkyl acetylenedicarboxylates the sequence provides the corresponding α,ω‐di(N‐pyrrolyl)alkanes.  相似文献   
6.
The general blueprint for the design of monoamine oxidase-B (MAO-B) inhibitors has been based on two phenyl or heteronuclei linked via a spacer of appropriate length. In this study, 1-[4-(morpholin-4-yl)phenyl]-5-phenylpenta-2,4-dien-1-one (MO10) was prepared by the condensation of 4′-morpholinoacetophenone and cinnamaldehyde in basic alcoholic medium. MO10 was assessed for inhibitory activity against two human MAO isoforms, MAO-A and MAO-B. Interestingly, MO10 showed a remarkable inhibition against MAO-B with an IC50 value of 0.044 μM along with a selectivity index of 366.13. The IC50 value was better than that of lazabemide (IC50 value of 0.063 μM), which was used as a reference. Kinetics studies revealed that MO10 acted as a competitive inhibitor of MAO-B, with a Ki value of 0.0080 μM. The observation of recovery of MAO-B inhibition, compared to reference levels showed MO10 to be a reversible inhibitor. MTT assays showed that MO10 was nontoxic to normal VERO cells with an IC50 value of 195.44 μg/mL. SwissADME predicted that MO10 provided advantageous pharmacokinetics profiles for developing agents acting on the central nervous system, that is, high passive human gastrointestinal absorption and blood–brain barrier permeability. Molecular docking simulations showed that MO10 properly entered the aromatic cage formed by Y435, Y398, and FAD of the active site of MAO-B. On the basis of these results, MO10 can be considered a promising starting compound in development of agents for the treatment of various neurodegenerative disorders.  相似文献   
7.
We propose to study the scattering properties of dense distributions of spherical scatterers by resorting to an iterative solution of the Foldy-Twersky equation for the propagation of the coherent field. As a result of the first step of the iterative procedure, the host medium is substituted by an effective medium of complex refractive index to account for the multiple-scattering processes that occur among the particles. Although we truncate the above-mentioned iterative procedure to the second step, the results of our calculations are in excellent agreement with previous experimental results of Zaccanti et al. ("Measurement of optical properties of high-density media," to be published in Applied Optics) for the scattering coefficient of Intralipid solutions up to a volume density of 15% and show a limited disagreement at a volume density of 22%.  相似文献   
8.
Different fluoroquinolon-type antibiotics were conjugated to gelatin with the aim to synthesize biomacromolecules with antimicrobial properties. The covalent linkage of the antibiotic was performed by a radical process involving the residues in the side chains of gelatin able to undergo oxidative modifications. The conjugation of antibiotic moieties onto the protein structure was confirmed by FT-IR, UV–Vis, fluorescence, and calorimetric analyses. Biocompatibility tests were performed on human bone marrow mesenchymal stromal cells and the antibacterial properties of bioactive polymers were investigated by appropriate tests against Klebsiella pneumoniae and Escherichia coli. With regard to the tests conducted in the presence of E. coli, a minimum inhibitory concentration (MIC) ranging from 0.05 to 0.40 μg mL?1 was recorded, while in the presence of K. pneumoniae this concentration varies from 0.10 to 1.60 μg mL?1. In all the conjugates, the drug moieties retain their biological activity and the MIC values are lower than the resistance parameters of fluoroquinolon-type antibiotics versus Enterobacteriacae. The collected data suggest a broad range of applications, from biomedical to pharmaceutical and food science for all conjugates.  相似文献   
9.
Achalasia is an esophageal smooth muscle motility disorder with unknown pathogenesis. Taking into account our previous results on the downexpression of miR-200c-3p in tissues of patients with achalasia correlated with an increased expression of PRKG1, SULF1, and SYDE1 genes, our aim was to explore the unknown biological interaction between these genes and human miR-200c-3p and if this relation could unravel their functional role in the etiology of achalasia. To search for putative miR-200c-3p binding sites in the 3′-UTR of PRKG1, SULF1 and SYDE1, a bioinformatics tool was used. To test whether PRKG1, SULF1, and SYDE1 are targeted by miR-200c-3p, a dual-luciferase reporter assay and quantitative PCR on HEK293 and fibroblast cell lines were performed. To explore the biological correlation between PRKG1 and miR-200c-3p, an immunoblot analysis was carried out. The overexpression of miR-200c-3p reduced the luciferase activity in cells transfected with a luciferase reporter containing a fragment of the 3′-UTR regions of PRKG1, SULF1, and SYDE1 which included the miR-200c-3p seed sequence. The deletion of the miR-200c-3p seed sequence from the 3′-UTR fragments abrogated this reduction. A negative correlation between miR-200c-3p and PRKG1, SULF1, and SYDE1 expression levels was observed. Finally, a reduction of the endogenous level of PRKG1 in cells overexpressing miR-200c-3p was detected. Our study provides, for the first time, functional evidence about the PRKG1 gene as a direct target and SULF1 and SYDE1 as potential indirect substrates of miR-200c-3p and suggests the involvement of NO/cGMP/PKG signaling in the pathogenesis of achalasia.  相似文献   
10.
This paper reports on the development and the optimization of a thermoforming process (compression molding) for thermoplastic sandwich panels. The skins of the panels are fabricated from polypropylene (PP)/continuous glass fibers dry prepregs in the form of a commingled fabric. The use of two different types of core material has been used, a PP foam and a PP honeycomb. Additionally, two alternative methods for the thermoforming process have been analyzed, using either a one-stage or a two-stage process. In the one-step process, skin molding and skin-core bonding are carried out simultaneously. In the two-stage process, the skins are first thermoformed and then bonded to the core as the second stage. The influence of the selected process parameters on the mechanical properties of the panels has been experimentally investigated, leading to the identification of the preferred processing conditions. Polym. Compos. 25:307–318, 2004. © 2004 Society of Plastics Engineers.  相似文献   
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