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21.

Background

A multi centre double-blind randomised-controlled trial (M-RCT), carried out in the Netherlands in 2005–2007, showed that hospitalised patients with S. aureus nasal carriage who were treated prophylactically with mupirocin nasal ointment and chlorhexidine gluconate medicated soap (MUP-CHX), had a significantly lower risk of health-care associated S. aureus infections than patients receiving placebo (3.4% vs. 7.7%, RR 0.42, 95% CI 0.23–0.75). The objective of the present study was to determine whether treatment of patients undergoing elective cardiothoracic or orthopaedic surgery with MUP-CHX (screen-and-treat strategy) affected the costs of patient care.

Methods

We compared hospital costs of patients undergoing cardiothoracic or orthopaedic surgery (n = 415) in one of the participating centres of the M-RCT. Data from the ‘Planning and Control’ department were used to calculate total hospital costs of the patients. Total costs were calculated including nursing days, costs of surgery, costs for laboratory and radiological tests, functional assessments and other costs. Costs for personnel, materials and overhead were also included. Mean costs in the two treatment arms were compared using the t-test for equality of means (two-tailed). Subgroup analysis was performed for cardiothoracic and orthopaedic patients.

Results

An investigator-blinded analysis revealed that costs of care in the treatment arm (MUP-CHX, n = 210) were on average €1911 lower per patient than costs of care in the placebo arm (n = 205) (€8602 vs. €10513, p = 0.01). Subgroup analysis showed that MUP-CHX treated cardiothoracic patients cost €2841 less (n = 280, €9628 vs €12469, p = 0.006) and orthopaedic patients €955 less than non-treated patients (n = 135, €6097 vs €7052, p = 0.05).

Conclusions

In conclusion, in patients undergoing cardiothoracic or orthopaedic surgery, screening for S. aureus nasal carriage and treating carriers with MUP-CHX results in a substantial reduction of hospital costs.  相似文献   
22.
We have compared the abilities of ascorbate and reduced glutathione (GSH) to act as intracellular free radical scavengers and protect cells against radical-mediated lipid peroxidation. Phenoxyl radicals were generated in HL60 cells, through the action of their myeloperoxidase, by adding H2O2 and phenol. Normally cultured cells, which contain no ascorbate; cells that had been preloaded with ascorbate; and those that had been depleted of GSH with buthionine sulfoximine were investigated. Generation of phenoxyl radicals resulted in the oxidation of ascorbate and GSH. Ascorbate loss was much greater in the absence of GSH, and adding glucose gave GSH-dependent protection against ascorbate loss. Ascorbate, or glucose metabolism, had little effect on the GSH loss. Glutathionyl radical formation was detected by spin trapping with DMPO in cells lacking ascorbate, and the signal was suppressed by ascorbate loading. Addition of phenol plus H2O2 to the cells caused lipid peroxidation, as measured with C11-BODIPY. Peroxidation was greatest in cells that lacked both ascorbate and GSH. Either scavenger alone gave substantial inhibition but optimal protection was seen with both present. These results indicate that GSH and ascorbate can each act as an intracellular radical scavenger and protect against lipid peroxidation. With both present, ascorbate is preferred and acts as the ultimate radical sink for phenoxyl or glutathionyl radicals. However, GSH is still consumed by metabolically recycling dehydroascorbate. Thus, recycling scavenging by ascorbate does not spare GSH, but it does enable the two antioxidants to provide more protection against lipid peroxidation than either alone.  相似文献   
23.
Iodothyronine 5'-deiodinase activity of rat liver microsomes was rapidly and completely lost by treatment with diethylpyrocarbonate (DEP) and by photo-oxidation with Rose Bengal (RB). In both cases inactivation followed pseudo first order reaction kinetics. Inactivation by DEP was diminished in the presence of substrate or competitive inhibitors, and was reversed by hydroxylamine treatment. In addition to photo-oxidation, deiodinase activity was also inhibited by RB in the dark. This inhibition was reversible and competitive with substrate (Ki 60 nM). These results suggest the location of an essential histidine residue at or near the active site of rat liver iodothyronine deiodinase.  相似文献   
24.
Plant growth can be studied at different organizational levels, varying from cell, leaf, and shoot to the whole plant. The early growth of seedlings is important for the plant's establishment and its eventual success. Wheat (Triticum aestivum, genome AABBDD) seedlings exhibit a low early growth rate or early vigor. The germplasm of wheat is limited. Wild relatives constitute a source of genetic variation. We explored the physiological and genetic relationships among a range of early vigor traits in Aegilops tauschii, the D-genome donor. A genetic map was constructed with amplified fragment-length polymorphism and simple sequence repeat markers, and quantitative trait loci (QTL) analysis was performed on the F(4) population of recombinant inbred lines derived from a cross between contrasting accessions. The genetic map consisted of 10 linkage groups, which were assigned to the seven chromosomes and covered 68% of the D genome. QTL analysis revealed 87 mapped QTLs (log of the odds >2.65) in clusters, 3.1 QTLs per trait, explaining 32% of the phenotypic variance. Chromosomes 1D, 4D, and 7D harbored QTLs for relative growth rate, biomass allocation, specific leaf area, leaf area ratio, and unit leaf rate. Chromosome 2D covered QTLs for rate and duration of leaf elongation, cell production rate, and cell length. Chromosome 5D harbored QTLs for the total leaf mass and area and growth rate of the number of leaves and tillers. The results show that several physiological correlations between growth traits have a genetic basis. Genetic links between traits are not absolute, opening perspectives for identification of favorable alleles in A. tauschii to improve early vigor in wheat.  相似文献   
25.
26.
Thyroid hormone uptake into primary cultured rat hepatocytes was studied using 1-min incubations with radio-iodine-labelled iodothyronines. (1) Uptake of thyroxine indicates two saturable sites apparent Km values of 1.2 nM and 1.0 μM, and non-saturable uptake. Similar kinetics of triiodothyronine uptake have been observed. (2) The high-affinity systems of both hormones are energy-dependent (i.e., inhibited by KCN and oligomycin). It is postulated that these systems represent active transport of thyroid hormone into the cell. (3) Analysis of mutual inhibition by the substrates for the triiodothyronine and thyroxine transport systems indicates that triiodothyromine and thyroxine cross the cell membrane via separate transport systems. (4) Preincubation with ouabain resulted in a decrease in uptake of both triiodothyronine and thyroxine, suggesting that a sodium gradient is essential for this transport.  相似文献   
27.
28.
Protoplasts from dark-grown wheat (Triticum aestivum L.) maintained at a constant osmotic potential at 22°C, were found to swell upon red irradiation (R) and the effect was negated by subsequent far-red light (FR), indicating phytochrome involvement. Swelling only occurred when Ca2+ ions were present in the surrounding medium, or were added within 10 min after R. Furthermore, Mg2+, Ba2+ or K+ could not replace this requirement for Ca2+. The presence of K+ did not enhance the Ca2+-dependent swelling response. When the Ca2+-ionophore A 23187 was added to the medium, protoplasts swelled in the dark to the same extent as after R. Both the Ca2+-channelblocker Verapamil and La3+ inhibited R-induced swelling. It is proposed that R causes the opening of Ca2+-channels in the plasma membrane. Boyle-van't Hoff analyses of protoplast volume after R and FR are consistent with the conclusion that R irradiation causes changes in membrane properties.Abbreviations EDTA ethylenediaminetetraacetic acid - FR far-red light - nov non-osmotic-volume - Pfr FR-absorbing form of phytochrome - Pr R-absorbing form of phytochrome - R red light  相似文献   
29.

Background

In the Netherlands, caesarean sections (CSs) are rarely combined with tubal occlusion (TO), partly because discussing CS/TO near delivery is considered unethical and earlier hypothetical counselling – i.e. suppose you happen to need a CS – is rare. This results in more unintended pregnancies and is inconsistent with informed choice. We explored whether TO should indeed not be made routinely available to eligible women.

Methods and Findings

A questionnaire was mailed to 515 Para ≥2 who underwent in the past ≥1 CS. 498 (96.7%) responded. They were on average 35.3 years old, had 2.5 children, had undergone 1.6 CSs, and 3.3 years had passed since their index delivery, either a CS (393) or vaginal birth (105) after a previous CS. 87% of the 498 believed that pregnant mothers with ≥1 children should be routinely counselled about CS/TO. Indeed, 58% and 85% respectively, thought women/couples expecting their second or third child should still be given the TO option days before delivery, if omitted earlier. Counselled women, 138/498 (27.8%), were far more often satisfied than those without CS/TO option. 33/393 had a CS/TO. None indicated regret in the questionnaire. Another 119 also would have elected a CS/TO if given that option. Therefore, 152 (38.7%) of 393 Para ≥2 had or would have liked a concurrent TO. 118/119 wrote they still regretted missing this opportunity. The exception''s husband had had a vasectomy. 100/119 were good TO candidates: they were ≥28 years when they delivered an apparently healthy baby of ≥37 weeks. The current contraceptive use of these 100 suggests that this group will have at least 8 unintended pregnancies before age 50.

Conclusion

The experiences and opinions of previous potential candidates for a CS/TO do not support the reluctance of Dutch obstetricians to counsel pregnant Para ≥1 about the TO option for a (potential) CS.  相似文献   
30.
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