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31.
Short-term risk of death after treatment with nesiritide for decompensated heart failure: a pooled analysis of randomized controlled trials 总被引:36,自引:8,他引:36
Context Nesiritide improves symptoms in patients with acutely decompensated heart failure compared with placebo and appears to be safer than dobutamine. Its short-term safety relative to standard diuretic and vasodilator therapies is less clear. Objective To investigate the safety of nesiritide relative to noninotrope-based control therapies, primarily consisting of diuretics or vasodilators. Data Sources Primary reports of completed clinical trials as of December 2004 were obtained from the US Food and Drug Administration (FDA), the study sponsor (Scios Inc), a PubMed literature search using the terms nesiritide, clinical trials, and humans, and a manual search of annual meetings of 3 heart associations. Study Selection Of 12 randomized controlled trials evaluating nesiritide, 3 met all inclusion criteria: randomized double-blind study of patients with acutely decompensated heart failure, therapy administered as single infusion (6 hours), inotrope not mandated as control, and reported 30-day mortality. Data Extraction Data were extracted from FDA and sponsor documents and corroborated with published articles when available. Thirty-day survival was assessed by meta-analysis using a fixed-effects model and time-dependent risk by Kaplan-Meier analysis with Cox proportional hazards regression modeling. Where deaths were described within a range of days after treatment, an extreme assumption was made favoring nesiritide over control therapy, an approach relevant to the time-dependent analyses. Data Synthesis In the 3 trials, 485 patients were randomized to nesiritide and 377 to control therapy. Death within 30 days tended to occur more often among patients randomized to nesiritide therapy (35 [7.2%] of 485 vs 15 [4.0%] of 377 patients; risk ratio from meta-analysis, 1.74; 95% confidence interval [CI], 0.97-3.12; P = .059; and hazard ratio after adjusting for study, 1.80; 95% CI, 0.98-3.31; P = .057). Conclusions Compared with noninotrope-based control therapy, nesiritide may be associated with an increased risk of death after treatment for acutely decompensated heart failure. The possibility of an increased risk of death should be investigated in a large-scale, adequately powered, controlled trial before routine use of nesiritide for acutely decompensated heart failure. 相似文献
32.
Numerous studies have shown that the geometry of micro-joints significantly affects the strength of the so joined timber element. The bending strength increases by creating a larger bonding area by increasing the length of the wedge joint. Although this type of joint has been successfully used for many years, it can still be troublesome to make. For these reasons, the present study investigated an easy-to-fabricate wedge joint, which we folded during the beams’ formation and glued with the same adhesive as the individual lamellas. Although the research has not fully answered all the questions relevant to both scientific and technological curiosity, it indicates the great potential of this solution. Following the principle adopted in the ongoing wood optimisation work, we concluded that the beams of the target cross-section should be produced, and it should only be possible to cut them to a certain length. In this approach, we only removed defects at critical points for the beam structure and, in this way, up to 30% of the timber processed could be saved or better utilised. 相似文献
33.
Katarzyna Kobiela-Mendrek Marcin Bczek Jan Broda Monika Rom Ingvild Espelien Ingun Klepp 《Materials》2022,15(9)
Wool of mountain sheep, treated nowadays as a waste or troublesome byproduct of sheep husbandry, was used for the production of sound-absorbing materials. Felts of two different thicknesses were produced from loose fibres. Additionally, two types of yarn, ring spun and core rug, were obtained. The yarns were used for the production of tufted fabric with cut and loop piles. During the examinations, basic parameters of the obtained materials were determined. Then, according to standard procedure with the use of impedance tube, the sound absorption coefficient was measured, and the noise reduction coefficient (NRC) was calculated. It was revealed that felt produced from coarse wool exhibits high porosity, and its sound absorbing capacity is strongly related to the felt thickness. For thicker felt the NRC achieved 0.4, which is comparable with the NRC of commercial ceiling tiles. It was shown that the crucial parameter influencing the sound absorption of the tufted fabrics was the pile height. For both types of yarns, when the height of the pile was increased from 12 to 16 mm, the NRC increased from 0.4 to 0.42. The manufactured materials made from local wool possess good absorption capacity, similar to commercial products usually made from more expensive wool types. The materials look nice and can be used for noise reduction as inner acoustic screens, panels, or carpets. 相似文献
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35.
Marcin Markowski Adam Kaliński Joanna Skwarska Jarosław Wawrzyniak Mirosława Bańbura Janusz Markowski Piotr Zieliński Jerzy Bańbura 《Bulletin of environmental contamination and toxicology》2013,91(3):302-305
The aim of this study was to determine the possibility of using feathers of blue tit nestlings to assess the level of endogenous accumulation of lead. For this purpose we conducted an experiment with lead application to randomly chosen nestlings from eight randomly drawn broods. Five days after the exposure, feathers of lead-treated nestlings had significantly higher lead concentrations than control nestlings. This result suggests that feathers can be used as reliable non-destructive bioindicators to assess the level of heavy metals originating from contaminated food, which is of great significance for comparative studies on ecological consequences of pollution. 相似文献
36.
After reaching adulthood, orderly repair is probably one of the most important mechanisms throughout lifetime. Regular wound healing after an injury consists of a well-ordered sequence of overlapping phases of repair and essentially repeats the complex process of organ development. Organ failure in the ageing organism frequently represents the lost capacity to achieve an orderly reactivation of organ development, yet in varying and complex pathologic settings. One of the most aggressive manifestations of age-dependent and dysbalanced wound healing is a disease called idiopathic pulmonary fibrosis. Essentially, the disease replaces functional lung tissue with spreading scar tissue over a period of just 5 years. By a systematic comparison of wound healing conditions, the large-scale collaborative FP7-EU project RESOLVE has addressed these difficulties in a successful way. Background and outlining of the project are discussed. 相似文献
37.
Jan Marcin Węsławski Lucyna Kryla-Straszewska Jan Warzocha Jacek Urbański Maria Włodarska-Kowalczuk Lech Kotwicki 《Oceanological and hydrobiological studies.》2013,42(3):289-295
Extensive sampling (450 grabs) was performed all over the inner part of Puck Bay (105 km2 area) in summers of 2007–2009. The GIS-based analysis of samples was performed to assess in detail the distribution of 32 benthic species. The minimum area of occurrence was less than 1 km2 for Lekanosphaera rugicauda and the maximum was 83 km2 for Cerastoderma glaucum. The material reveals that species with the pelagic larval stage were most widespread, with the least distance between individuals and the highest average density (e.g. Cerastoderma glaucum, Hydrobia ventrosa). The most isolated and the least dense species within the studied area were discretely mobile, non-larval crustaceans (e.g. Gammarus oceanicus and Lekanosphaera rugicauda), present at single sites with the largest distance from each other. We conclude that analysis of species distribution helps in understanding the threats to populations of marine invertebrates and marine spatial planning, through locating the isolated species and populations. 相似文献
38.
39.
Tomasz Jazwiec Marcin Malinowski Haley Ferguson Jeremy Wodarek Nathan Quay Jared Bush Matthew Goehler Jessica Parker Manuel Rausch Tomasz A. Timek 《The Journal of thoracic and cardiovascular surgery》2021,161(4):e277-e286
ObjectiveTo investigate the effect of variable tricuspid annular reduction (TAR) on functional tricuspid regurgitation (FTR) and right ventricular (RV) dynamics in ovine tachycardia-induced cardiomyopathy.MethodsNine adult sheep underwent implantation of a pacemaker with an epicardial lead and were paced at 200 to 240 bpm until the development of biventricular dysfunction and functional TR was noted. During reoperation on cardiopulmonary bypass, 6 sonomicrometry crystals were placed around the tricuspid annulus (TA) and 14 were placed on the RV epicardium. Annuloplasty suture was placed around the TA and externalized to an epicardial tourniquet. After weaning from cardiopulmonary bypass, echocardiographic, hemodynamic, and sonomicrometry data were acquired at baseline and during 5 progressive TARs achieved with suture cinching. TA area and RV free wall strains and function were calculated from crystal coordinates.ResultsAfter pacing, changes in left ventricular (LV) ejection fraction and RV fractional area decreased significantly. Mean TA diameter increased from 25.1 ± 2.9 mm to 31.5 ± 3.3 mm (P = .005), and median TR (range, 0-3+) increased from 0 (0) to 3 (2) (P = .004). Progressive suture cinching reduced the TA area by 18 ± 6%, 38 ± 11%, 56 ± 10%, 67 ± 9%, and 76 ± 8%. Only aggressive annular reductions (67% and 76%) decreased TR significantly, but these were associated with deterioration of RV function and strain. A moderate annular reduction of 56% led to a substantial reduction of TR with little deleterious effect on regional RV function.ConclusionsA moderate TAR of approximately 50% may be most advantageous for correction of functional TR and simultaneous maintenance of regional RV performance. Additional subvalvular interventions may be needed to achieve complete valvular competence. 相似文献
40.
Aleksandra Cieluch Aleksandra Uruska Marcin Nowicki Ewa Wysocka Agata Grzelka-Woźniak Justyna Flotyńska Paweł Niedźwiecki Dorota Zozulińska-Ziółkiewicz 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(4):1219-1226
Background and aimsCholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) are crucial proteins in reverse cholesterol transport. There are insufficient data on regulating these proteins by insulin therapy in type 1 diabetes mellitus (T1DM). We aimed to assess prospectively the impact of insulin therapy initiation on transfer proteins serum levels in adults with newly diagnosed T1DM.Methods and results57 adults with newly diagnosed T1DM were enrolled in the InLipoDiab1 Study. All participants were treated with subcutaneous insulin in the model of intensive insulin therapy since the diagnosis of diabetes. Serum PLTP and CETP concentrations were measured at diagnosis, after three weeks, six months, and after one year of insulin treatment, using the immunoenzymatic method ELISA.A significant decrease in PLTP and CETP concentrations were demonstrated during twelve months of insulin therapy in newly diagnosed T1DM. The dynamics of changes in the level of these proteins varied depending on the occurrence of remission after a year of the disease. In the group without remission, a significant decrease in PLTP and CETP levels appeared after six months of follow-up. The remission group was characterized by a decrease in proteins concentration only after one year of treatment. In the non-remission group, significant negative correlations were found between the daily dose of insulin and levels of PLTP and CETP.ConclusionExogenous insulin is an inhibitor of lipid transfer proteins involved in high-density lipoprotein cholesterol metabolism in the first year of treatment. 相似文献