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91.
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93.

Background and Design

In this study we set out to determine the effects of long-term physical training on hemorheological, laboratory parameters, exercise tolerability, psychological factors in cardiac patients participating in an ambulatory rehabilitation program.

Methods

Before physical training, patients were examined by echocardiography, tested on treadmill by the Bruce protocol, and blood was drawn for laboratory tests. The enrolled 79 ischemic heart disease patients joined a 24-week cardiac rehabilitation training program. Blood was drawn to measure hematocrit (Hct), plasma and whole blood viscosity (PV, WBV), red blood cell (RBC) aggregation and deformability. Hemorheological, clinical chemistry and psychological measurements were repeated 12 and 24 weeks later, and a treadmill test was performed at the end of the program.

Results

After 12 weeks Hct, PV, WBV and RBC aggregation were significantly decreased, RBC deformability exhibited a significant increase (p<0.05). Laboratory parameters (triglyceride, uric acid, hsCRP and fibrinogen) were significantly decreased (p<0.05). After 24 weeks the significant results were still observed. By the end of the study, IL-6 and TNF-α levels displayed decreasing trends (p<0.06). There was a significant improvement in MET (p<0.001), and the BMI decrease was also significant (p<0.05). The vital exhaustion parameters measured on the fatigue impact scale indicated a significant improvement in two areas of the daily activities (p<0.05).

Conclusions

Regular physical training improved the exercise tolerability of patients with ischemic heart disease. Previous publications have demonstrated that decreases in Hct and PV may reduce cardiovascular risk, while a decrease in RBC aggregation and an increase in deformability improve the capillary flow. Positive changes in laboratory parameters and body weight may indicate better oxidative and inflammatory circumstances and an improved metabolic state. The psychological findings point to an improvement in the quality of life.  相似文献   
94.
Alternative pre-mRNA processing is a central element of eukaryotic gene regulation. The cell frequently alters the use of alternative exons in response to physiological stimuli. Ceramides are lipid-signaling molecules composed of sphingosine and a fatty acid. Previously, water-insoluble ceramides were shown to change alternative splicing and decrease SR-protein phosphorylation by activating protein phosphatase-1 (PP1). To gain further mechanistical insight into ceramide-mediated alternative splicing, we analyzed the effect of C6 pyridinium ceramide (PyrCer) on alternative splice site selection. PyrCer is a water-soluble ceramide analog that is under investigation as a cancer drug. We found that PyrCer binds to the PP1 catalytic subunit and inhibits the dephosphorylation of several splicing regulatory proteins containing the evolutionarily conserved RVxF PP1-binding motif (including PSF/SFPQ, Tra2-beta1 and SF2/ASF). In contrast to natural ceramides, PyrCer promotes phosphorylation of splicing factors. Exons that are regulated by PyrCer have in common suboptimal splice sites, are unusually short and share two 4-nt motifs, GAAR and CAAG. They are dependent on PSF/SFPQ, whose phosphorylation is regulated by PyrCer. Our results indicate that lipids can influence pre-mRNA processing by regulating the phosphorylation status of specific regulatory factors, which is mediated by protein phosphatase activity.  相似文献   
95.
Grassland restoration on former croplands offers good opportunity to mitigate the loss of grassland biodiversity. Weed suppression can be another benefit, which becomes increasingly important because of the high recent rate of abandonment of arable lands in Central and Eastern Europe. Our aim was to evaluate the usefulness of sowing two low-diversity seed mixtures followed by annual mowing, a frequently used restoration technique, in weed suppression. We found that rapidly forming cover of sown grasses effectively suppressed short-lived weeds and their germination except in the first year. The detected dense seed bank of short-lived weeds points out the possibility and threat of later weed infestation. In the short run perennial weeds cannot be suppressed easily by sowing and annual mowing. We found that the effectiveness of seed sowing followed by mowing in weed suppression can be different on sites with different history or seed mixture. Rapidly establishing perennial weeds, such as Agropyron species were only detected in former alfalfa fields; Cirsium arvense was found in former cereal and sunflower fields but not in former alfalfa fields. We found that the rate of weed suppression and success was influenced by the seed mixtures used. In several alkali restorations the high proportion of perennial weeds was detected in year 3. In loess restorations, much lower scores were typical. This was likely caused by the different seed mixture used. The loess seed mixture contained seeds of a clonally spreading tall-grass, Bromus inermis, which could compete more effectively with clonally spreading weeds, than could short grass species with or without tussock forming. Our findings indicate that post-restoration management require carefully designed actions that are fine-tuned addressing specific threats at the site level.  相似文献   
96.
The linear hypertrophic scar has become the most common type of pathologic scarring. Silicone-gel sheeting is the first line therapy while intralesional steroid is the second. A light and electron microscopic analysis was carried out to reveal differences in tissue reaction following the two different treatments. Two groups of 12 patients each were treated for 4 months. For the first group, diluted Triamcinolone acetonide was injected until an inactive state was achieved. The other group of patients was treated with silicone-gel sheeting. The scars were examined every two weeks and their appearance documented. After reaching the expected therapeutic response, inactive scars were removed. The excised scars were evaluated through light microscopic histopathology and electron microscopy. The light and electron microscopic observations revealed marked differences following treatments. The activity of fibroblasts and the numbers of collagen fibers forming bundles decreased and the orientation of the collagen fibers was more variable in the treated scars. The amount of elastic fibers increased after both steroid and silicone-gel sheeting treatment. Vascularization was also slightly changed, with more capillaries and fewer pre-capillary arteries detected in the treated scars. Both treatments resulted in the same decrease in score but steroid treatment was more rapid in onset. We suggest that the two different treatments work through different mechanisms, although the final functional outcome is similar.  相似文献   
97.
Early biochemical analyses of metabolic pathways assumed that the free diffusion of substrates and enzymes in an evenly mixed cellular space provided the interactions that enabled reactions to proceed. Metabolic complexes have since been shown to assemble and disassemble in response to changes in cellular conditions, and in turn, to channel metabolic intermediates within discreet cellular compartments, allowing for the efficient use or storage of energy. A fundamental component to the formation of metabolic complexes and the channeling of metabolites is the translocation of enzymes in response to specific extra- and intracellular signals. These generalities play an important role in the metabolism of glucose to glycogen within skeletal muscle and liver. In this review, the similarities and differences in skeletal muscle and liver glucose metabolism with regards to glucose transport and intracellular processing will be addressed during the fasted to fed transition. More specifically, the importance of isoform expression and protein translocation in the tissue specific control of glucose homeostasis will be covered.  相似文献   
98.
Background, Aims and Scope  Telework is associated with a number of costs and benefits, including reduced company overhead costs, need for office and parking space, office energy consumption, increased productivity, reduced absenteeism, retention of specialized employees, reduction in transportation-related fuel consumption and air pollution, and many others. This paper applies a systems model to telework and nontelework scenarios to quantify direct energy and fuel costs and external costs related to air emissions from transportation, heating, cooling, lighting, and electronic and electrical equipment use both at the company and the home office, including rebound effects. Methods  E-COMMUTair, a scalable web-based tool created by the authors and designed to assess the air pollution effects of individual or company telework programs versus nontelework is employed along with Monte Carlo simulation and sensitivity analysis. E-COMMUTair is using the latest available U.S. energy use and air emission factors. The external costs of air emissions are estimated. The role of telecommuting frequency is emphasized, and differences between various states are explored. The paper identifies the drivers of external costs, and presents an example breakeven analysis focused on CO2 and key model parameters. Results and Discussion  Nontelework’s external costs are equal to or higher than telework’s costs for every model component, demonstrating that telework programs could provide benefits, including monetary benefits, to society. Transportation is the major contributor to the total costs, with home heating and cooling, and office cooling following. Most of the monetary costs associated with transportation are borne by individuals rather than society. Teleworking employees increase their home-related expenses but reduce their travel-related expenses, ending up with smaller total costs. Energy and fuel costs get reduced in the office space when telework programs are applied, resulting in benefits to companies. Energy and external costs decrease as telework frequency increases. When compared to not teleworking, 5-day telework scenarios on cooling days in California can have about 50–70% lower total costs. The probabilistic analysis confirms the results of the deterministic analysis. The sensitivity analysis reveals that for the nontelework scenario, transportation-related variables such as commuting distance and average number of passengers affect CO2, CO, and NOx emissions, while for the telework part, frequency and the number of roundtrips are the most relevant. Conclusions  Both analyses show that telework programs have the potential to lower both energy and external costs creating a favorable bottom line for society, employees, and companies by decreasing tailpipe emissions, lowering transportation costs, and decreasing energy costs at the company office. However, important parameters such as telecommuting frequency, characteristics of the office and home space, climate patterns, and rebound effects that determine external costs along with the price of gasoline, electricity and natural gas in the state where the program is implemented can greatly influence the final results, and should be carefully examined. Recommendations and Perspectives  The effects of telework programs on people’s daily lives are complex and difficult to predict and quantify. The current analysis showed that significant financial benefits can be expected from telework programs, but as seen often in environmental policy-making, the details of implementation will make or break the success of a program. formerly Postdoctoral Researcher, University of California, Berkeley ESS-Submission Editor: Dr. Gerald Rebitzer (Gerald.Rebitzer@alcan.com)  相似文献   
99.
In this study, the thermoluminescence (TL) characteristics of Ag‐doped and undoped lithium tetraborate (Li2B4O7, LTB) materials, grown using the Czochralski method, were reported. The TL properties of LTB:Ag, such as glow curve structure, dose response, fading and reproducibility, were investigated. The glow curve of the Li2B4O7:Ag single crystal consists of four peaks located at approximately 75, 130, 190 and 275°C; in undoped LTB, the single crystal shows a broad glow curve with peaks at 65, 90, 125, 160 and 190°C using a heating rate of 5°C/s in the 50–350°C temperature region. The high temperature peak of Ag‐doped sample at 275°C has a nonlinear dose response within the range from 33 mGy to 9 Gy. There is a linear response in the range of 33–800 mGy; after which, a sublinear region appears up to 9 Gy for Ag‐doped LTB single crystal. For undoped single crystal, the dose response is supralinear for low doses and linear for the region between 1 and 9 Gy. The thermal fading ratio of the undoped material is almost 60% for the high temperature peak after 7 days. Ag‐doped LTB single crystal exhibits different behaviour over a period of 7 days.  相似文献   
100.
Functional analyses of placental protein 13/galectin-13.   总被引:7,自引:0,他引:7  
Placental protein 13 (PP13) was cloned from human term placenta. As sequence analyses, alignments and computational modelling showed its conserved structural and functional homology to members of the galectin family, the protein was designated galectin-13. Similar to human eosinophil Charcot-Leyden crystal protein/galectin-10 but not other galectins, its weak lysophospholipase activity was confirmed by 31P-NMR. In this study, recombinant PP13/galectin-13 was expressed and specific monoclonal antibody to PP13 was developed. Endogenous lysophospholipase activity of both the purified and also the recombinant protein was verified. Sugar binding assays revealed that N-acetyl-lactosamine, mannose and N-acetyl-glucosamine residues widely expressed in human placenta had the strongest binding affinity to both the purified and recombinant PP13/galectin-13, which also effectively agglutinated erythrocytes. The protein was found to be a homodimer of 16 kDa subunits linked together by disulphide bonds, a phenomenon differing from the noncovalent dimerization of previously known prototype galectins. Furthermore, reducing agents were shown to decrease its sugar binding activity and abolish its haemagglutination. Phosphorylation sites were computed on PP13/galectin-13, and phosphorylation of the purified protein was confirmed. Using affinity chromatography, PAGE, MALDI-TOF MS and post source decay, annexin II and beta/gamma actin were identified as proteins specifically bound to PP13/galectin-13 in placenta and fetal hepatic cells. Perinuclear staining of the syncytiotrophoblasts showed its expression in these cells, while strong labelling of the syncytiotrophoblasts' brush border membrane confirmed its galectin-like externalization to the cell surface. Knowing its colocalization and specific binding to annexin II, PP13/galectin-13 was assumed to be secreted to the outer cell surface by ectocytosis, in microvesicles containing actin and annexin II. With regard to our functional and immunomorphological results, PP13/galectin-13 may have special haemostatic and immunobiological functions at the lining of the common feto-maternal blood-spaces or developmental role in the placenta.  相似文献   
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