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61.
Ruben Scholten Keetie Kremers Sebastiaan A.W. van de Groes Diederik M. Somford Sander Koëter 《The Journal of arthroplasty》2018,33(5):1546-1551
Background
Postoperative urinary retention (POUR) appears to be a common complication in lower limb joint arthroplasty; however, reports on its incidence vary. There is no general consensus on its definition and there is no scientific evidence on treatment principles. We performed a prospective observational study to establish the incidence of POUR and its risk factors, including the preoperative postvoid residual urine volume and the perioperative fluid balance, in fast-track total joint arthroplasty (TJA). The preoperative residual urine volume and the perioperative fluid balance have not been studied in previous literature in the context of TJA and POUR.Methods
Three hundred eighty-one patients who underwent TJA of the lower limb were observed on developing POUR according to our local treatment protocol. Data on possible risk factors for POUR were collected including the perioperative fluid balance and the preoperative residual urine volume.Results
In total, 46.3% of patients were catheterized. A preoperative postvoid urine retention is a significant predictor of catheterization for postoperative residual urine (P = .03). Spinal anesthesia was correlated with urinary retention (P = .01). There was no cause-effect relationship between POUR and the perioperative fluid balance.Conclusion
This study underlines POUR as a common complication in fast-track lower limb arthroplasty, with spinal anesthesia as a risk factor. A higher preoperative residual urine volume leads to higher postoperative residual volume, but not to a higher change in urinary retention. Increased perioperative fluid administration is not correlated with the incidence of POUR. Furthermore, there seems to be little rationale for monitoring residual urine volume both preoperatively and postoperatively. 相似文献62.
Blood group A immunodeterminants on human red cells differ in biologic activity and sensitivity to alpha-N-acetylgalactosaminidase 总被引:1,自引:0,他引:1
BACKGROUND: Epitopes of blood group A antigen can be enzymatically cleaved from red cells (RBCs), but the extent of cleavage required for normal survival in allogeneic blood transfusion recipients is unknown. Therefore, the cleavage rates were studied for A antigen epitope binding of 1) complement-activating anti-A, 2) Dolichos biflorus anti- A, lectin, and 3) hemagglutinating anti-A during incubation with a purified alpha-N-acetylgalactosaminidase, E.C. 3.2.1.49 (alpha- GalNAc'ase). STUDY DESIGN AND METHODS: Suspensions of group A RBCs were incubated with alpha-GalNAc'ase. Cells were removed at intervals, washed, and tested for loss of binding by monoclonal, polyclonal, and complement-activating anti-A, D. biflorus anti-A1 lectin, and Ulex europaeus anti-H lectin. RESULTS: A epitopes binding D. biflorus lectin were highly susceptible to alpha-GalNAc'ase; simultaneously with their loss, binding with U. europaeus lectin emerged. Loss of complement- mediated hemolysis was slower. A epitopes binding hemagglutinating anti- A were most resistant. Cleavage of A epitopes from membrane glycosphingolipids with short oligosaccharide chains was similarly resistant. Rates of cleavage from A1 and A2 RBCs were similar. CONCLUSION: RBC epitopes of blood group A differ in susceptibility to cleavage and biologic reactivity, which suggests that subsets mediating important biologic functions exist on functionally and topographically distinct membrane glycoconjugates. 相似文献
63.
BACKGROUND: Concern over the theoretical possibility of disease transmission via blood from donors who develop Creutzfeldt-Jakob disease has led to proposals to exclude older individuals from donating plasma for further manufacture into pooled plasma donations. The impact of extending this age-deferral policy to blood donors was examined with respect to the risk for known transmissible viruses. STUDY DESIGN AND METHODS: Demographic characteristics and confirmed prevalence rates (/10(5) first-time donations) and incidence rates (/10(5) person-years for repeat donors) for viral markers were compared for donors < 50 years old (n = 1,259,805 [85%]) and > or = 50 years old (n = 219,856 [15%]) and for donors < 60 years old (n = 1,409,176 [95%]) and > or = 60 years old (n = 70,485 [5%]). Incidence rates were combined with infectious window-period estimates for each virus, to calculate the risk of virus transmission per 10(6) donations. RESULTS: Unadjusted prevalence rates were significantly greater for younger than for older donor groups for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), and hepatitis C virus (HCV) (p < or = 0.05). Incidence rates (and transmission risk estimates) for HBsAg were significantly higher in the < 50 donor group than in the > or = 50 group (p < or = 0.05), and those for HIV, human T-lymphotropic virus, and HCV were not significantly higher (p > 0.05). Blanket removal of donors over the age of 50 would potentially lead to the following significant increases in the risk of infected units: HIV, 12 percent; HCV, 21 percent; and hepatitis B virus (HBsAg), 22 percent. CONCLUSION: Removal of donors over the age of 60 would not significantly affect the risk of infected units. Deferral of donors > or = 50 years of age from whole-blood donations for unfounded concerns about Creutzfeldt-Jakob disease could have adverse effects on both blood availability and safety. 相似文献
64.
Joel Charrow Cristina Fraga Xuefan Gu Hiroyuki Ida Nicola Longo Elena Lukina Alexandre Nonino Sebastiaan J.M. Gaemers Marie-Helene Jouvin Jing Li Yaoshi Wu Yong Xue M. Judith Peterschmitt 《Molecular genetics and metabolism》2018,123(3):347-356
Eliglustat is a first-line oral therapy for adults with Gaucher disease type 1 (GD1) with compatible CYP2D6-metabolizer phenotypes (> 90% of patients). The randomized, double-blind EDGE trial (NCT01074944, Sanofi Genzyme) evaluated once-daily eliglustat dosing compared with the approved twice-daily regimen at the same total daily dose in adults with GD1. Subjects received twice-daily dosing during a 6- to 18-month lead-in period. Only subjects who attained prespecified treatment goals for hemoglobin, platelet count, spleen and liver volumes, and bone symptoms during the lead-in period were randomized to once- or twice-daily dosing. Of 170 enrolled patients, 156 completed the lead-in period and 131 met all requirements to enter the double-blind treatment period. To achieve the composite primary endpoint in the double-blind period, patients had to maintain clinical stability relative to baseline on all five endpoints (hemoglobin, platelet count, spleen and liver volumes, and bone symptoms) and meet pharmacokinetic and other tolerability requirements as determined by the investigator after 1 year of eliglustat treatment. After 1 year, 80.4% (95% CI: 67.6, 89.8) of once-daily patients were stable compared with 83.1% (95% CI: 71.0, 91.6) of twice-daily patients. The 95% CI for the mean difference of ? 2.7% between groups was ? 17.7, 11.9. Because the lower bound of the CI exceeded the pre-defined non-inferiority margin of ? 15%, once-daily dosing could not be declared non-inferior to twice-daily dosing. Both once-daily and twice-daily patients maintained mean values for hematologic and visceral measures within established therapeutic goals during the double-blind treatment and long-term extension periods. Eliglustat was generally well-tolerated during this long-term trial (mean treatment duration: 3.3 years), with just four withdrawals (2%) for related adverse events (AE), and similar AE profiles for both dosing regimens. Patients on twice-daily eliglustat showed more stability overall, and this dose regimen was better tolerated, confirming the dosing regimen for most patients specified in the drug label. 相似文献
65.
壳聚糖/聚乙二醇琥珀酸酯薄膜的制备及其与肌成纤维细胞的相容性 总被引:1,自引:0,他引:1
目的:制备防粘连壳聚糖/聚乙二醇琥珀酸酯薄膜并观察其与肌成纤维细胞的相容性。方法:实验于2006-05/11在南方医科大学附属珠江医院中心实验室完成。实验材料:在透析后的壳聚糖与聚乙二醇琥珀酸酯或聚乙二醇共混后置入冻干机冻干制得壳聚糖/聚乙二醇琥珀酸酯薄膜或壳聚糖/聚乙二醇膜,并将新生2~5d的SD大鼠骨骼肌成纤维细胞种植于膜片上。实验评估:①MTT法测定肌成纤维细胞接种在不同膜片上的吸光度值,计算相对贴附率。相对贴附率=不同膜的A490nm/培养板的A490nm×100%。②MTT法测定肌成纤维细胞在不同膜片上的生长1,5d后的吸光度值。③相差显微镜下观察肌成纤维细胞的生长形貌。结果:①肌成纤维细胞在不同膜片上的贴附率:肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯薄膜上能良好黏附、增殖,而在壳聚糖/聚乙二醇膜、壳聚糖膜上黏附性差。联合培养12h,5d后MTT法结果显示,壳聚糖/聚乙二醇琥珀酸酯组的A值分别为0.074±0.009,0.141±0.031,分别为壳聚糖组的6.17倍和6.13倍(P〈0.05)。②肌成纤维细胞的生长特性:肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯膜上的活性最高,增殖能力最强,增长速度最快,其次为壳聚糖/聚乙二醇膜,但两者差异无显著性意义(P〉0.05),而细胞在壳聚糖膜上的增殖能力较低,膜上细胞数目较少,与其他组比较差异有显著性意义(P〈0.05)。③肌成纤维细胞与不同膜片联合培养1,5d时的生长形貌:壳聚糖膜上细胞未贴壁生长,为透明的圆球形,呈游离状态,未能很好舒展,且有些皱缩,生长活力也不旺盛;细胞与壳聚糖/聚乙二醇膜、壳聚糖/聚乙二醇琥珀酸酯膜片联合培养的生长情况要明显好于壳聚糖膜,细胞相互融合成片,多呈长梭形,细胞间隙狭窄,紧密排列成束,成指纹状结构且聚集生长的趋势也更明显。结论:将接支琥珀酰基的聚乙二醇与壳聚糖共混组成的网状系统改进了膜片的力学性能,提高了膜片的柔韧性,使其成膜性更好;壳聚糖/聚乙二醇琥珀酸酯薄膜具有良好的生物相容性,肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯薄膜上的黏附及生长情况明显好于壳聚糖薄膜。 相似文献
66.
Sebastiaan A. A. P. Hocksel MSc Johannes A. Blom PhD Jos R. C. Jansen PhD Jan J. Schreuder MD PhD 《Journal of clinical monitoring and computing》1996,12(5):397-403
Objective. To develop an algorithm that corrects pulmonary artery pressure signals of ventilated patients for the respiration artifact. The algorithm should test the validity of the pulmonary pressure signal and differentiate between the cyclic respiration artifact and true measurement artifacts.Methods. The shape of each pulmonary pressure beat is described by eight characteristic features, including mean pressure value and the systolic and diastolic timing and pressure values. The features are corrected for the respiration artifact by fitting them in a least-squares sense on the first and second harmonica of the ventilator frequency. The corrected features are used by a signal validation algorithm, which adds a validity flag to each pressure beat. The validation algorithm rejects pressure beats with sudden changes in their shape but adapts itself when the changes persist.Results. The performance of the correction and validation technique was evaluated using pulmonary artery pressure signals of 30 patients who were scheduled for open heart surgery. The algorithm correctly recognized as invalid data those pressure signals disturbed by coagulation, surgical manipulations, or flushes of the pressure line. The algorithm marked on average 77 ± 11 % of the pulmonary pressure beats as valid.Conclusions. The validation algorithm marked sufficient pressure beats as valid to update a trend display every 5 sec. The correction algorithm enabled the validation algorithm to differentiate between true measurement artifacts and the respiration artifact. 相似文献
67.
68.
Bezemer R Dobbe JG Bartels SA Christiaan Boerma E Elbers PW Heger M Ince C 《Medical & biological engineering & computing》2011,49(11):1269-1278
The purpose of this study was to develop a rapid and fully automatic method for the assessment of microvascular density and
perfusion in sidestream dark field (SDF) images. We modified algorithms previously developed by our group for microvascular
density assessment and introduced a new method for microvascular perfusion assessment. To validate the new algorithm for microvascular
density assessment, we reanalyzed a selection of SDF video clips (n = 325) from a study in intensive care patients and compared the results to (semi-)manually found microvascular densities.
The method for microvascular perfusion assessment (temporal SDF image contrast analysis, tSICA) was tested in several video
simulations and in one high quality SDF video clip where the microcirculation was imaged before and during circulatory arrest
in a cardiac surgery patient. We found that the new method for microvascular density assessment was very rapid (<30 s/clip)
and correlated excellently with (semi-)manually measured microvascular density. The new method for microvascular perfusion
assessment (tSICA) was shown to be limited by high cell densities and velocities, which severely impedes the applicability
of this method in real SDF images. Hence, here we present a validated method for rapid and fully automatic assessment of microvascular
density in SDF images. The new method was shown to be much faster than the conventional (semi-)manual method. Due to current
SDF imaging hardware limitations, we were not able to automatically detect microvascular perfusion. 相似文献
69.
Kristel Sleegers Nathalie Brouwers Karolien Bettens Sebastiaan Engelborghs Helen van Miegroet Peter P De Deyn Christine Van Broeckhoven 《Human mutation》2009,30(4):E570-E574
A non‐synonymous polymorphism, rs2986017 (p.P86L), in the newly characterized calcium homeostasis modulator 1 (CALHM1) gene located in the Alzheimer dementia (AD) linkage region on 10q24.33, was reported to increase risk of AD, and affect calcium homeostasis and amyloid β accumulation. We aimed to investigate the association between this functional polymorphism and AD in an independent study population. We genotyped rs2986017 in 362 Belgian AD patients and 519 ethnically matched control individuals. We found no evidence of association between rs2986017 and risk of disease, nor did we find an effect on onset age. Despite its functional properties, our study suggests the polymorphism does not contribute significantly to AD risk in the Belgian population. © 2009 Wiley‐Liss, Inc. 相似文献
70.
van Tuyl SA Letteboer TG Rogge-Wolf C Kuipers EJ Snijder RJ Westermann CJ Stolk MF 《European journal of gastroenterology & hepatology》2007,19(2):153-158
INTRODUCTION: Hereditary hemorrhagic teleangiectasia (HHT) is an autosomal dominant disorder with mucocutaneous teleangiectasia and visceral arteriovenous malformations. Mutations of endoglin and Activin A receptor like kinase-1 have different phenotypes, HHT1 and HHT2, respectively. The gastrointestinal tract is frequently affected, but limited information is available on the relationship with genotype. AIM: To determine whether different genotypes have different phenotypes with respect to intestinal teleangiectasia. METHODS: HHT patients, referred for anemia, underwent videocapsule endoscopy. Chart review was performed for information on genotype and HHT manifestations. RESULTS: Twenty-five patients were analyzed (men/women 13/9, mean age 49+/-15 years.), 14 HHT1, eight HHT2 and three without known mutation. Epistaxis occurred in 96% of patients. Gastroduodenoscopy revealed teleangiectasia in 7/12 (58%) HHT1 and 3/8 (38%) HHT2 patients. Videocapsule endoscopy found teleangiectasia in all HHT1 and 5/8 (63%) HHT2 patients. In 9/14 HHT1 patients, teleangiectasia were large. Teleangiectasia in the colon was restricted to 6/11 (55%) HHT1 patients. Hepatic arteriovenous malformations were present in 1/7 HHT1 and 5/6 HHT2 patients. CONCLUSION: Large teleangiectasia in small intestine and colon appear to occur predominantly in HHT1. Hepatic arteriovenous malformations are mainly found in HHT2. In HHT patients with unexplained anemia, videocapsule endoscopy should be considered to determine the size and extent of teleangiectasia and exclude other abnormalities. 相似文献