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排序方式: 共有1047条查询结果,搜索用时 15 毫秒
101.
Murphy MF Casbard AC Ballard S Shulman IA Heddle N Aubuchon JP Wendel S Thomson A Hervig T Downes K Carey PM Dzik WH;BEST Research Collaborative 《Transfusion》2007,47(5):771-780
BACKGROUND: Transfusion of the incorrect blood component is a frequent serious incident associated with transfusion and often involves misidentification of the patient and/or the unit of blood. The objective of this study was to assess the effect of a simple intervention designed to improve performance of the bedside check and to observe the durability of any effect. The intervention was a tag on blood bags reminding staff to check the patient's wristband. The tag was positioned in such a way that the transfusionist was required to remove the tag to spike the unit. STUDY DESIGN AND METHODS: The intervention was tested in a multicenter cluster-randomized controlled trial incorporating short-term and long-term follow-up periods. The primary endpoint was the proportion of patients transfused with red cell units for whom the key elements of the bedside check were all correctly completed. RESULTS: Fifteen matched-paired clinical areas at 12 participating hospitals in six countries were included in the trial. Combining data from all participating hospitals, the bedside check was correctly performed in 37 percent of transfusions during the baseline audit period. There was no evidence of a favorable effect of the intervention immediately after its introduction (pooled odds ratio, 1.09; 95% confidence interval, 0.54-2.17). There was similarly no evidence of a favorable effect after continued use of the intervention for an additional 8 weeks. CONCLUSIONS: A simple intervention in the form of a barrier warning label on blood bags reminding staff to check the patient's wristband failed to improve bedside transfusion practice. The robust study design developed for this study could be applied to investigate other interventions to improve the safety of bedside transfusion practice. 相似文献
102.
P. Schadewaldt H. -W. Hammen C. Dalle-Feste U. Wendel 《Journal of inherited metabolic disease》1990,13(2):137-150
Summary
l-Alloisoleucine formation froml-isoleucine was studiedin vitro andin vivo. When a healthy subject was loaded withl-isoleucine, plasma levels ofl-isoleucine and 3-methyl-2-oxopentanoate (KMV), as well asl-alloisoleucine, increased. Peak values were reached successively and were in the orderl-isoleucine > > KMV > >l-alloisoleucine. Metabolic clearance ofl-isoleucine and KMV was rapid; clearance ofl-alloisoleucine was considerably delayed. When human skin fibroblast cultures were challenged withl-isoleucine, KMV accumulated at a gradually decreased rate, whereasl-alloisoleucine accumulated at a gradually accelerated rate. KMV andl-alloisoleucine formation were related and depended on thel-isoleucine concentration applied. In cell lines derived from MSUD patients (classical form), metabolite formation was only about 2-fold higher than in control strains. The relatively small difference between normal and MSUD fibroblastsin vitro as opposed to the striking differences between healthy subjects and MSUD patientsin vivo are discussed with respect to the significance of physiological mechanisms participating in the formation and degradation ofl-alloisoleucine in man. 相似文献
103.
Schwahn BC Wendel U Lussier-Cacan S Mar MH Zeisel SH Leclerc D Castro C Garrow TA Rozen R 《Metabolism: clinical and experimental》2004,53(5):594-599
Cystathionine-β-synthase (CBS) is required for transsulfuration of homocysteine, an amino acid implicated in vascular disease. We studied homocysteine metabolism in mice with mild hyperhomocysteinemia due to a heterozygous disruption of the Cbs gene. Mice were fed diets supplemented with betaine or dimethylsulfonioacetate (DMSA); betaine and DMSA provide methyl groups for an alternate pathway of homocysteine metabolism, remethylation by betaine:homocysteine methyltransferase (BHMT). On control diets, heterozygous mice had 50% higher plasma homocysteine than did wild-type mice. Betaine and DMSA had similar effects in both genotype groups: liver betaine increased dramatically, while plasma homocysteine decreased by 40% to 50%. With increasing betaine supplementation, homocysteine decreased by 75%. Plasma homocysteine and BHMT activity both showed a strong negative correlation with liver betaine. Homocysteinemia in mice is sensitive to a disruption of Cbs and to methyl donor intake. Because betaine leads to a greater flux through BHMT and lowers homocysteine, betaine supplementation may be beneficial in mild hyperhomocysteinemia. 相似文献
104.
S. M. Baker R. V. Sugars M. Wendel A. J. Smith R. J. Waddington P. R. Cooper A. J. Sloan 《Calcified tissue international》2009,85(1):66-74
TGF-β isoforms sequestrated in dentin matrix potentially provide a reservoir of bioactive molecules that may influence cell
behavior in the dentin–pulp complex following tissue injury. The association of these growth factors with dentin matrix and
the influence of such associations on the bioactivity of growth factors are still unclear. We used surface plasmon resonance
technology in the BIAcoreTM 3000 system to investigate the binding of TGF-β isoforms 1 and 3 to purified decorin, biglycan, and EDTA soluble dentin matrix
components. TGF-β isoforms 1 and 3 were immobilized on sensorchips CM4 through amine coupling. For kinetic studies of protein
binding, purified decorin and biglycan, isolated EDTA soluble dentin matrix, and dentin matrix immunodepleted of decorin and/or
biglycan were injected over TGF-β isoforms and allowed to interact. Programmed kinetic analysis software provided sensorgrams
for each concentration of proteoglycan or dentin matrix extract injected. Purified decorin and biglycan and dentin matrix
extract bound to the TGF-β isoforms. However, the association with TGF-β3 was much weaker than that with TGF-β1. After immunoaffinity
depletion of the dentin matrix extract, the level of interaction between the dentin matrix extract and TGF-β was significantly
reduced. These results suggest isoform-specific interactions between decorin/biglycan and TGF-β isoforms 1 and 3, which may
explain why TGF-β3 is not detected in the dentin matrix despite being expressed at higher levels than TGF-β1 in odontoblasts.
These proteoglycans appear to play a significant role in TGF-β/extracellular matrix interactions and may be important in the
sequestration of these growth factors in the dentin matrix. 相似文献
105.
Proinflammatory mediators as well as increased formation of reactive oxygen and nitrogen species impair cellular respiration during sepsis. In particular, the highly reactive peroxynitrite irreversibly damages lipids, proteins and nucleic acids and also inhibits enzyme complexes of the respiratory chain. In this way cellular metabolic functions and subsequently organ functions are also impaired. Repair of DNA by poly(ADP-ribose)polymerase consumes large amounts of nicotinamide adenine dinucleotide (NAD+) which leads to cellular NAD+ depletion further promoting inflammation. This article summarizes central aspects of the pathophysiology of mitochondrial dysfunction during sepsis and gives an overview about newly developed strategies which proved effective in experimental studies and may have a potential clinical application in the future. 相似文献
106.
Cooling of the patient is routinely applied in cardiac surgery to protect organs against ischemia. Hypothermia induces activation of platelets, but the effects of temperatures such as used during cardiac surgery are not well described. To investigate this in an in-vitro study heparinized whole blood was incubated at different temperatures (37 degrees C, 34.5 degrees C, 32 degrees C, 29.5 degrees C, 27 degrees C, 24.5 degrees C, 22 degrees C, 19.5 degrees C and 17 degrees C). The effect of these temperatures on aggregation, P-selectin expression, GP IIb/IIIa activation and platelet microparticle (PMP) formation of unstimulated and ADP-stimulated platelets of 36 subjects was evaluated in flow cytometry. A four-parametric logistic model was fitted to depict the temperature effect on platelet parameters. Lower temperatures increased aggregates, P-selectin expression, and GP IIb/IIIa activation. The number of PMPs decreases with hypothermia. Additional experiments revealed a slight influence of heparin on platelet P-selectin expression but excluded an effect of this anticoagulant on the other evaluated parameters. Threshold temperatures, which mark 5% changes of platelet parameters compared to values at 37 degrees C, were calculated. On ADP-stimulated platelets the thresholds for P-selectin expression and GP IIb/IIa activation are 34.0 degrees C and 36.4 degrees C, respectively, and lie in the temperature range routinely applied in cardiac surgery. Hypothermia-induced platelet activation may develop in most patients undergoing cardiac surgery, possibly resulting in thromboembolic events, coagulation defects, and proinflammatory leukocyte bridging by P-selectin bearing platelets and PMPs. These findings suggest that pharmacological protection of platelets against hypothermia-induced damage may be beneficial during cardiac surgery. 相似文献
107.
Ladetzki-Baehs K Keller M Kiemer AK Koch E Zahler S Wendel A Vollmar AM 《Endocrinology》2007,148(1):332-336
Natriuretic peptides (NPs) comprise a family of vasoactive hormones that play important roles in the regulation of cardiovascular and renal homeostasis. Along this line, atrial NP (ANP) (international non-proprietary name: carperitide, HANP) is an approved drug for the treatment of acute heart failure. In recent years, evidence has been given that the NP system possesses a far broader biological spectrum than the regulation of blood pressure and volume homeostasis. In fact, a substantial amount of in vitro work indicates that ANP affects important inflammatory processes and signaling pathways. Quite surprisingly, however, no information exists on the in vivo antiinflammatory potential and signaling of ANP. We show here that pretreatment of lipopolysaccharide (Salmonella abortus equi, 2.5 mg/kg)-challenged mice with ANP (5 microg/kg iv, 15 min) rapidly inhibits nuclear factor-kappaB activation via inhibition of phosphorylation and degradation of the IkappaB-alpha protein. ANP also reduces Akt activation upon lipopolysaccharide injection. In ANP-pretreated mice, the increase of TNF-alpha serum concentration is markedly prevented; most importantly, the survival of these animals improved. These findings demonstrate both in vitro and in vivo an antiinflammatory profile of ANP that deserves to be further investigated in a therapeutic perspective. 相似文献
108.
Jain S McGory ML Ko CY Sverdlik A Tomlinson JS Wendel CS Coons SJ Rawl SM Schmidt CM Grant M McCorkle R Mohler MJ Baldwin CM Krouse RS 《American journal of surgery》2007,194(6):774-9; discussion 779
BACKGROUND: Previous research suggests an ostomy worsens health-related quality of life (HR-QOL), but comorbidities also can affect HR-QOL. METHODS: Eligible patients had abdominal operation with ostomy (cases) or similar procedure without ostomy (controls). Patients were recruited for this case-control study from 3 Veterans Affairs hospital medical and pharmacy records. Comorbidities were assessed with Charlson-Deyo Comorbidity Index. Multinomial logistic regression evaluated the impact of comorbidities and having an ostomy on HR-QOL, measured using the Medical Outcomes Study Short Form 36 for Veterans. RESULTS: A total of 237 ostomates (cases) and 268 controls were studied. Average age was 69 years; 64% of cases had colostomy, 36% ileostomy. Twenty-nine percent of patients had a high level of comorbidities. Cases and controls were similar except for reasons for undergoing surgery. High comorbidity was a significant predictor of low HR-QOL in 6 domains of the Short Form 36 for Veterans; having an ostomy was a significant predictor in 4. CONCLUSIONS: High comorbidity significantly influences low HR-QOL and impacted more domains than having an ostomy. 相似文献
109.
Therapeutic suppression of translation initiation modulates chemosensitivity in a mouse lymphoma model 总被引:1,自引:0,他引:1
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Bordeleau ME Robert F Gerard B Lindqvist L Chen SM Wendel HG Brem B Greger H Lowe SW Porco JA Pelletier J 《The Journal of clinical investigation》2008,118(7):2651-2660
Disablement of cell death programs in cancer cells contributes to drug resistance and in some cases has been associated with altered translational control. As eukaryotic translation initiation factor 4E (eIF4E) cooperates with c-Myc during lymphomagenesis, induces drug resistance, and is a genetic modifier of the rapamycin response, we have investigated the effect of dysregulation of the ribosome recruitment phase of translation initiation on tumor progression and chemosensitivity. eIF4E is a subunit of eIF4F, a complex that stimulates ribosome recruitment during translation initiation by delivering the DEAD-box RNA helicase eIF4A to the 5' end of mRNAs. eIF4A is thought to prepare a ribosome landing pad on mRNA templates for incoming 40S ribosomes (and associated factors). Using small molecule screening, we found that cyclopenta[b]benzofuran flavaglines, a class of natural products, modulate eIF4A activity and inhibit translation initiation. One member of this class of compounds, silvestrol, was able to enhance chemosensitivity in a mouse lymphoma model in which carcinogenesis is driven by phosphatase and tensin homolog (PTEN) inactivation or elevated eIF4E levels. These results establish that targeting translation initiation can restore drug sensitivity in vivo and provide an approach to modulating chemosensitivity. 相似文献
110.
Genetic diversity in Hypericum and AFLP Markers for species-specific identification of H. perforatum L 总被引:2,自引:0,他引:2
One of the top-selling medicinal products worldwide is Hypericum perforatum (St. John's Wort). Despite its cosmopolitan distribution and utilization, little is known regarding the relationship of the bioactive compounds in H. perforatum to the plants from which they are purportedly derived. In this study, amplified fragment length polymorphism (AFLP) analysis of 56 Hypericum accessions, representing 11 species, was conducted to gain a better understanding of diversity within Hypericum species, especially within cultivated accessions of H. perforatum, and to establish a molecular methodology that will provide breeders and regulators with a simple, affordable, and accurate tool with which to identify purported H. perforatum material. Utilizing four primer combinations, a total of 298 polymorphic markers were generated, of which 17 were present in all H. perforatum accessions and 2 were specific to only H. perforatum. This study demonstrates that AFLP can be utilized not only to determine the relationships of closely related Hypericum accessions, but as a tool to authenticate material in herbal remedies through the use of genetic fingerprinting. 相似文献