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1.
PURPOSE: To evaluate long-term efficacy of double balloon percutaneous mitral valvuloplasty technique (PMV2B). METHODS: Sixty-eight patients (76% female), mean-age 32 (15-69) years who had been submitted to PMV2B, that completed clinical and echodopplercardiographic one year follow-up (PO12M). Admission criteria were: exertional dyspnoea, no thromboembolism antecedent up to three months before the procedure, absence of other cardiac disease requiring correction, an admissible echodopplercardiographic score, absence of intracavitary thrombus and mitral regurgitation absent or minor. RESULTS: The patients were divided in two groups: group A of 7 (11%) patients that have a cardiac event in this period, and group B of 61 patients that completed the follow-up without a cardiac event. In group A three patients have had a severe mitral regurgitation, one case was unsuccessful and other one had a re-stenosis. There were two deaths, not related to the intervention. In group B, haemodynamic results before and immediately after PMV2B (POI) showed a significant improvement, except in relation to cardiac index. There was an increase in the grade of mitral regurgitation in 17 (28%) patients and in two cases this regurgitation became moderate. The mitral valvar area (MVA) variation between PRE x POI x PO12M presented, comparing MVA between POI and PO12M, a significant reduction. Two (3%) patients with a reduction greater than 50% of the initial increase, 33 (54%) between 10 and 50% and 26 (42%) less that 10% remained in functional class I/II. CONCLUSION: PMV2B is an attractive treatment to select symptomatic mitral stenosis patients, with a low incidence of complications, symptomatic effective improvement that was maintained in one year follow-up, although there was a reduction in MVA.  相似文献   
2.
Are there differences in eating behaviour between obese and non-obese children? Using the parent version of the Dutch Eating Behaviour Questionnaire (DEBQ-parent version), the results of the present study suggest an affirmative answer to this question. The scores for obese children were significantly higher on the scales for emotional, external and restrained eating behaviour. Relationships were found between emotional eating and negative feelings of physical competence; between external eating and negative feelings of self-worth; and between both eating styles and various aspects of problem behaviour. No relationship was found between external eating and locus of control. Higher scores on both scales were associated with greater caloric intake. These findings suggest that DEBQ can be used as a screening instrument for assessing eating styles of obese children.  相似文献   
3.
This article describes the cytoskeleton associated with fenestrae and sieve plates of rat liver sinusoidal endothelial cells. Fenestrae control the exchange between the blood and parenchymal cells. We present evidence indicating that several agents that change the fenestrae and sieve plates also cause changes in the cytoskeleton. Cultured liver endothelial cells (LECs) were slightly fixed and treated with cytoskeleton extraction buffer. Detergent-extracted whole mounts of cultured cells were prepared for either scanning electron microscopy (SEM) or transmission electron microscopy (TEM). Extracted cells show an integral intricate cytoskeleton; sieve plates and fenestrae are delineated by cytoskeleton elements. Fenestrae are surrounded by a filamentous, fenestrae-associated cytoskeleton with a mean filament thickness of 16 nm. Sieve plates are surrounded and delineated by microtubuli, which form a network together with additional branching cytoskeletal elements. The addition of ethanol to cultured cells enlarged the diameter for these fenestrae-associated cytoskeleton rings by 5%, whereas serotonin treatment reduced the diameter by 20%. These observations indicate that the fenestrae-associated cytoskeleton probably changes the size of fenestrae after different treatments. After treatment with cytochalasin B the number of fenestrae increased. However, cytochalasin B did not change the structure of the fenestrae-associated cytoskeleton ring, but disperses the microtubuli. In conclusion, LECs have a cytoskeleton that defines and supports sieve plates and fenestrae. Fenestrae-associated cytoskeleton is a dynamic structure and plays a role in maintaining and regulating the size of fenestrae after different treatments. Therefore, the fenestrae-associated cytoskeleton controls the important hepatic function of endothelial filtration.  相似文献   
4.
The authors investigated the morphology and the elastic properties of living cultured rat liver macrophages (Kupffer cells) with an atomic force microscope (AFM). Continuous imaging and elasticity mapping of individual cells in physiological buffer was carried out for several hours without damaging the cells as judged by their persistent undisturbed morphology. Dynamic events such as protrusive activity were observed in time course. The importance of the cytoskeleton for the mechanical properties of the cell has been investigated by measuring the cell's elasticity as a function of position. Chemical disassembly of the actin network by applying 10 microgram/ml cytochalasin B decreased the cell's average elastic modulus seven-fold within less than 40 minutes. Treating the cells with 0.1 micrograms/ml latrunculin A resulted in a two-fold decrease in the elastic modulus merely in the perinuclear region after 40 minutes, whereas other parts of the cell were not affected.  相似文献   
5.
Breweries are exporting their brands overseas, resulting in an increasingly competitive and globalised beer market. Inevitably, the beer experiences varying and prolonged periods of transport and storage prior to consumption. During this process, the flavour of fresh beer deteriorates, leading to the presence of stale flavours and a decrease in the drinkability of the beer. Results reported here show that an increased temperature during beer transport and storage causes significant flavour deterioration, as determined analytically (increase in aldehydes, beer colour and haze formation, decrease in iso‐α‐acids concentration) and sensorially (increase in overall aging score). Further, laboratory experiments show that the vibration of beer results in a rapid decrease of oxygen. Moreover, inappropriate storage temperature has a negative effect on beer quality and stability, in particular when combined with vibration. © 2018 The Institute of Brewing & Distilling  相似文献   
6.
Atomic force microscopy (AFM) has been used to image a wide variety of cells. Fixed and dried-coated, wet-fixed or living cells were investigated. The major advantage of AFM over SEM is the avoidance of vacuum and electrons, whereas imaging can be done at environmental pressure and in aqueous conditions. Evidence of the successful application of AFM in biological imaging is provided by comparing results of AFM with SEM and/or TEM. In this study, we investigated surface and submembranous structures of living and glutaraldehyde-fixed colon carcinoma cells, skin fibroblasts and liver macrophages by AFM. Special attention was paid to the correct conditions for the acquisition of images of the surface of these cells, because quality SEM examinations have already been abundantly presented.
AFM imaging of living cells revealed specific structures, such as the cytoskeleton, which were not observed by SEM. Membrane structures, such as ruffles, lamellipodia, microspikes and microvilli, could only clearly be observed after fixing the cells with 0.1% glutaraldehyde. AFM images of living cells were comparable to SEM images of fixed, dried and coated cells, but contained a number of artefacts due to tip–sample interaction. In addition, AFM imaging allowed the visualization of cytoplasmic submembranous structures without the necessity for further preparative steps, allowing us: (i) to follow cytoskeletal changes in fibroblasts under the influence of the microfilament disrupting agent latrunculin A; (ii) to study particle phagocytosis in macrophages. Therefore, in spite of the slow image acquisition of the AFM, the instrument can be used for high-resolution real-time studies of dynamic changes in submembranous structures.  相似文献   
7.
This study aimed to (a) assess relationships between the Children's Depression Inventory (CDI) and DSM-oriented depression and anxiety scales of the Youth Self Report, (b) develop reliable norms for the CDI, and (c) determine CDI cutoff scores for selecting youngsters at risk for depression and anxiety. A total of 3,073 nonclinical and 511 clinically referred children and adolescents from The Netherlands and Belgium were included. Results showed that CDI scores were significantly related to DSM-oriented symptoms of both depression and anxiety. CDI scores correlated highly with depression symptoms and moderately with anxiety symptoms. Norms for the CDI were determined by means of multiple regression analysis and depended on sex, age, and country. CDI cutoff scores for selecting individuals at risk for depression and anxiety as measured by the DSM-oriented depression and anxiety scales of the Youth Self Report were determined by means of multiple regression analysis and receiver operating characteristic analysis. A CDI score of 16 was found to have the most optimal balance between sensitivity and specificity for depression, whereas a score of 21 provided the best sensitivity and specificity for anxiety in a subsample of children. We conclude that the CDI is an effective instrument for screening depression and to a lesser extent anxiety in primary and secondary care centers, before applying further assessment of high-risk individuals. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
8.
In this report, a novel chemical synthesis of polyaniline/gold nanocomposite is explored using ionic liquid (IL) 1-Butyl-3-methylimidazolium hexafluorophosphate. The direct chemical synthesis of polyaniline/gold nanocomposite was initiated via the spontaneous oxidation of aniline by AuCl4 in IL. A nearly uniform dispersion of polyaniline/Au particles with a diameter of 450 ± 80 nm was produced by this method, which indicates that this method is more suitable for controlling particle dimensions. It was also found that the electrical conductivity of the polyaniline/gold nanocomposite was more than 100 times higher than that of the pure polyaniline nanoparticles. The polyaniline/gold nanocomposite displays superior function in the biocatalytic activation of microperoxidase-11 because of the high surface area of the assembly and the enhanced charge transport properties of the composite material. We also report the possible application of polyaniline/gold nanocomposite as a H2O2 biosensor.  相似文献   
9.
The chemotactic and growth-stimulatory effect of insulin-like growth factor 1 (IGF-1) was investigated in the experimental mouse 5T2 multiple myeloma (MM) model. Chemotaxis was analyzed by classical checkerboard analysis. Bone marrow fibroblasts-conditioned medium exhibited a chemotactic effect on 5T2 MM cells that could be neutralized by adding a blocking antibody to IGF-1. On the other hand, exogenously added IGF-1 also had a chemotactic effect on the 5T2 MM cells. Moreover, in vitro analysis demonstrated that transmigrated 5T2 MM cells have a higher expression of IGF-1 receptor, both in bone marrow-conditioned medium and in IGF-1-induced chemotaxis, in comparison to cells before migration. When analyzed in vivo, 18 hours after injection of the heterogeneous 5T2 MM population, 5T2 MM cells present in the bone marrow show a higher expression of the IGF-1 receptor than their counterparts before injection. When the proliferative effect of IGF-1 was analyzed, no stimulation was observed, which is in contrast to the influence of bone marrow-conditioned medium and interleukin-6. Our results suggest a causal relationship between the presence of IGF-1 in the bone marrow and the chemotaxis of MM cells to and their subsequent presence in the bone marrow.  相似文献   
10.
Cybr/Reduced On-random Motile (ROM) is a scaffold protein, containing a postsynaptic density protein-95/discs-large/ZO-1 (PDZ) domain, a LEU region and a PDZ domain binding region at the C-terminus. In the immune system, Cybr/ROM was found to localize in vesicles and at the plasma membrane, through interactions with cytohesin-1. In this investigation, we reported Cybr/ROM as occurring in vesicles, the cytoplasm and at membrane ruffles of H1299 lung cancer cells. Its localization at the ruffles was dependent on intact actin structures as indicated by latrunculin A treatment, which abrogated ruffle formation and staining of Cybr/ROM at the cells' periphery. Transfection of truncation mutants consisting of either the PDZ or LEU domain showed that the LEU domain of ROM was localized to membrane ruffles, vesicles and the cytoplasm, whereas, the PDZ domain localized to the membrane ruffles and cytoplasm only. There was therefore, domain/molecular segregation of Cybr/ROM in different cellular compartments. Cybr/ROM was subcloned into a plasmid carrying the photoactivation-mediated resonance energy transfer (Phamret) protein. The photoconversion experiments demonstrated the diffusion of ROM from the cytoplasm to the membrane ruffling sites and conversely from membrane ruffles to the cytoplasm. Large variances in the transport velocity of Cybr/ROM in the cytoplasm suggested that its movements were facilitated by other mechanisms in addition to diffusion.  相似文献   
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