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51.
O'Day SJ; Rabinowe SN; Neuberg D; Freedman AS; Soiffer RJ; Spector NA; Robertson MJ; Anderson K; Whelan M; Pesek K 《Blood》1994,83(9):2707-2714
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity. 相似文献
52.
Matthew Ahmadi Margaret O’Neil Maria Fragala-Pinkham Nancy Lennon Stewart Trost 《Journal of neuroengineering and rehabilitation》2018,15(1):105
Background
Cerebral palsy (CP) is the most common physical disability among children (2.5 to 3.6 cases per 1000 live births). Inadequate physical activity (PA) is a major problem effecting the health and well-being of children with CP. Practical, yet accurate measures of PA are needed to evaluate the effectiveness of surgical and therapy-based interventions to increase PA. Accelerometer-based motion sensors have become the standard for objectively measuring PA in children and adolescents; however, current methods for estimating physical activity intensity in children with CP are associated with significant error and may dramatically underestimate HPA in children with more severe mobility limitations. Machine learning (ML) models that first classify the PA type and then predict PA intensity or energy expenditure using activity specific regression equations may be more accurate than standalone regression models. However, the feasibility and validity of ML methods has not been explored in youth with CP. Therefore, the purpose of this study was to develop and test ML models for the automatic identification of PA type in ambulant children with CP.Methods
Twenty two children and adolescents (mean age: 12.8?±?2.9 y) with CP classified at GMFCS Levels I to III completed 7 activity trials while wearing an ActiGraph GT3X+ accelerometer on the hip and wrist. Trials were categorised as sedentary (SED), standing utilitarian movements (SUM), comfortable walking (CW), and brisk walking (BW). Random forest (RF), support vector machine (SVM), and binary decision tree (BDT) classifiers were trained with features extracted from the vector magnitude (VM) of the raw acceleration signal using 10?s non-overlapping windows. Performance was evaluated using leave-one-subject out cross validation.Results
SVM (82.0–89.0%) and RF (82.6–88.8%) provided significantly better classification accuracy than BDT (76.1–86.2%). Hip (82.7–85.5%) and wrist (76.1–82.6%) classifiers exhibited comparable prediction accuracy, while the combined hip and wrist (86.2–89.0%) classifiers achieved the best overall performance. For all classifiers, recognition accuracy was excellent for SED (94.1–97.9%), good to excellent for SUM (74.0–96.6%) and brisk walking (71.5–86.0%), and modest for comfortable walking (47.6–70.4%). When comfortable and brisk walking were combined into a single walking class, recognition accuracy ranged from 90.3 to 96.5%.Conclusions
ML methods provided acceptable classification accuracy for detection of a range of activities commonly performed by ambulatory children with CP. The resultant models can help clinicians more effectively monitor bouts of brisk walking in the community. The results indicate that 2-step models that first classify PA type and then predict energy expenditure using activity specific regression equations are worthy of exploration in this patient group.53.
Dual endothelin‐1 receptor antagonism attenuates platelet‐mediated derangements of blood coagulation in Eisenmenger syndrome 下载免费PDF全文
B. Kevane S. Allen K. Walsh K. Egan P. B. Maguire M. C. Galligan D. Kenny R. Savage E. Doran Á. Lennon E. Neary F. Ní Áinle 《Journal of thrombosis and haemostasis》2018,16(8):1572-1579
Essentials
- Eisenmenger syndrome is characterised by thrombotic and hemorrhagic risks of unclear aetiology.
- Calibrated automated thrombography was used to assess these coagulation derangements.
- Platelet activity supported abnormalities in procoagulant and anticoagulant pathway function.
- Endothelin‐1 antagonism appeared to ameliorate these derangements.
Summary
Aims
The mechanisms underlying the competing thrombotic and hemorrhagic risks in Eisenmenger syndrome are poorly understood. We aimed to characterize derangements of blood coagulation and to assess the effect of dual endothelin‐1 receptor antagonism in modulating hemostasis in this rare disorder.Methods
In a 10‐month recruitment period at a tertiary cardiology referral center, during which time there were over 14 000 outpatient consultations, consecutive subjects with Eisenmenger syndrome being considered for macitentan therapy (n = 9) and healthy volunteers (n = 9) were recruited. Plasma thrombin generation in platelet‐rich and platelet‐poor plasma was assessed by calibrated automated thrombography prior to and following therapy.Results
Median peak plasma thrombin generation was higher in platelet‐rich plasma obtained from Eisenmenger syndrome subjects relative to controls (median peak thrombin [25th–75th percentile]: 228.3 [206.5–258.6] nm vs. 169.9 [164.3–215.8] nm ), suggesting a critical mechanistic role for platelets in supporting abnormal hypercoagulability in Eisenmenger syndrome. Abnormal enhanced sensitivity to the anticoagulant activity of activated protein C was also observed in platelet‐rich plasma in Eisenmenger syndrome, suggesting that derangements of platelet activity may influence the activity of anticoagulant pathways in a manner that might promote bleeding in this disease state. Following 6 months of macitentan therapy, attenuations in the derangements in both procoagulant and anticoagulant pathways were observed.Conclusions
Abnormal platelet activity contributes to derangements in procoagulant and anticoagulant pathways in Eisenmenger syndrome. Therapies targeting the underlying vascular pathology appear to ameliorate these derangements and may represent a novel strategy for the management of the competing prothrombotic and hemorrhagic tendencies in this disorder.54.
Correlates of procedural complications and a simple integer risk score for percutaneous coronary intervention 总被引:3,自引:0,他引:3
Singh M Lennon RJ Holmes DR Bell MR Rihal CS 《Journal of the American College of Cardiology》2002,40(3):387-393
OBJECTIVES: Our goals were to identify clinical and angiographic risk factors associated with major cardiovascular complications of percutaneous coronary intervention (PCI) (in-hospital death, Q-wave myocardial infarction, urgent or emergent coronary artery bypass surgery and stroke) and to construct a simple score for risk stratification. BACKGROUND: Both clinical and angiographic features influence risk of PCIs. METHODS: Percutaneous coronary interventions performed between January 1, 1996, and December 31, 1999, were analyzed. Logistic regression and bootstrap methods were used to create an integer risk score for estimating the risk of procedural complications using baseline, angiographic and procedural characteristics. The risk score was tested in a validation-set consisting of all procedures performed in the year 2000. RESULTS: Among 5,463 procedures, 5 clinical and 3 angiographic variables were significantly correlated with procedural complications: cardiogenic shock, left main coronary artery disease, severe renal disease, urgent or emergent procedure, congestive heart failure class III or higher, thrombus, multivessel disease and older age. In the validation-set, the model fitted the data adequately; the average receiver operating characteristic curve area was 0.782 (standard deviation, 0.018). CONCLUSIONS: Eight variables were combined into a convenient bedside risk scoring system that estimates the risk of complications after PCIs. 相似文献
55.
Endoscopic sphincteroplasty: a novel and safe alternative to papillotomy in the management of bile duct stones. 总被引:7,自引:3,他引:7 下载免费PDF全文
Removal of bile duct stones during endoscopic retrograde cholangiopancreatography (ERCP) usually includes papillotomy. Papillotomy is associated with occasional complications and in addition, the longterm sequelae of papillotomy in young patients having laparoscopic cholecystectomy remain unclear. As an alternative to papillotomy, this study prospectively evaluated the efficacy and safety of endoscopic balloon sphincteroplasty to facilitate bile duct clearance. Of 32 patients with bile duct stones (diameter 3-30 mm) at ERCP, sphincteroplasty was considered inappropriate in four patients because of stone size (> 20 mm) necessitating papillotomy for bile duct clearance. Sphincteroplasty was performed in the remaining 28 patients to permit duct clearance by dormier basket, balloon or mechanical lithotripsy. The bile duct was cleared in 22 patients (79%) while additional measures including papillotomy or stent insertion were required in the remaining six patients (21%) because of stone size or technical difficulties. There was no associated papillary haemorrhage. Pancreatitis was seen in one patient (4%) but resolved within 24 hours. Our preliminary experience suggests that sphincteroplasty is a safe and effective sphincter preservation technique that significantly reduces the necessity for papillotomy in the management of bile duct stones. 相似文献
56.
Eric H Yang Richard J Gumina Ryan J Lennon David R Holmes Charanjit S Rihal Mandeep Singh 《Journal of the American College of Cardiology》2005,46(11):2004-2009
OBJECTIVES: The purpose of the current study was to evaluate the changes in incidence, clinical characteristics, and indications for emergency coronary artery bypass grafting (CABG) in patients undergoing percutaneous coronary intervention (PCI) from 1979 to 2003. BACKGROUND: Emergency CABG after PCI is associated with significant morbidity and mortality. METHODS: Data from 23,087 patients who underwent PCI at Mayo Clinic from 1979 to 2003 were analyzed. Patients were divided into three groups: the "pre-stent" era, 1979 to 1994 (n = 8,905); the "initial stent era," 1995 to 1999 (n = 7,605); and the "current stent era," 2000 to 2003 (n = 6,577). RESULTS: Although patients undergoing PCI in the recent time periods had more high-risk features, there was a significant decrease in the incidence of emergency CABG from 2.9% to 0.7% to 0.3% across the groups (p < 0.001). Patients requiring emergency surgery in the recent time periods had a higher prevalence of hypertension, prior revascularization, and left ventricular dysfunction (ejection fraction <40%), as well as more complex coronary lesions. Fewer patients in the current stent era had coronary artery dissections and abrupt vessel closure requiring emergency CABG. The in-hospital mortality rate for emergency CABG patients remains unchanged and ranges from 10% to 14%. CONCLUSIONS: The current study demonstrates that despite the increase in high-risk patients undergoing PCI, there has been a marked decrease in the incidence of patients requiring emergency CABG. However, the in-hospital mortality rate for those requiring emergency CABG remains high and unchanged. 相似文献
57.
The grey zone (GZ; 45–54 CGG repeats in the FMR1 gene) is considered a normal allele; however, several studies have found a high frequency of GZ in movement disordered populations. Here, we describe neurological features of fragile X‐associated tremor/ataxia syndrome (FXTAS) in two carriers of GZ alleles, although FXTAS has been defined as occurring only in premutation carriers (55–200 CGG repeats). Both patients had family members who had premutation and were diagnosed with FXTAS. The presence of relatively high GZ alleles with elevated fragile X mental retardation 1 mRNA (FMR1‐mRNA) combined with a family history of FXTAS that may represent a facilitating genetic background for FXTAS are the factors that led to the presence of FXTAS in these individuals with a GZ allele. Further research into clinical involvement of GZ alleles is recommended and the definition of FXTAS may require revision. 相似文献
58.
59.
Expression and function of CD40 on Hodgkin and Reed-Sternberg cells and the possible relevance for Hodgkin's disease 总被引:7,自引:2,他引:7
Gruss HJ; Hirschstein D; Wright B; Ulrich D; Caligiuri MA; Barcos M; Strockbine L; Armitage RJ; Dower SK 《Blood》1994,84(7):2305-2314
CD40 was originally described as a B-cell-restricted antigen and was subsequently found to be a member of the tumor necrosis factor (TNF) receptor superfamily. CD40 is also expressed on dendritic cells, thymic epithelium, monocytes, and some carcinoma cell lines, and plays a critical role in cell contact-dependent activation. Primary and cultured Hodgkin and Reed-Sternberg (H-RS) cells, the presumed malignant cells of Hodgkin's disease (HD); were found to express high levels of cell surface CD40. We found that recombinant CD40 ligand (CD40L) induced interleukin-8 (IL-8) secretion and enhanced IL-6, TNF, and lymphotoxin-alpha (LT-alpha/TNF-beta) release from cultured H-RS cells. These cytokines play a significant role in the clinical presentation and pathology of HD, a tumor of cytokine-producing cells. CD40L had no mitogenic activity for HD-derived cell lines. In contrast, CD40L enhanced expression of costimulatory molecules intracellular adhesion molecule-T and B7-1 on cultured H-RS cells, both of which are overexpressed on primary H-RS cells. In addition, CD40L induced a 40% to 60% reduction of the expression of the HD-associated CD30 antigen, another member of the TNF receptor superfamily. Primary and cultured H- RS cells express not only CD30, but also CD40. CD40L has pleiotropic biologic activities on H-RS cells, and the CD40-CD40L interaction might be a critical element in the deregulated cytokine network and cell contact-dependent activation cascade typical for HD. 相似文献
60.
Kameoka J; Sato T; Torimoto Y; Sugita K; Soiffer RJ; Schlossman SF; Ritz J; Morimoto C 《Blood》1995,85(4):1132-1137
Patients who have undergone allogeneic bone marrow transplantation (allo-BMT) are susceptible to a variety of opportunistic infectious complications in the months to years after engraftment. Impaired in vitro T-cell functions have been documented in these patients, and these T-cell dysfunctions contribute to the prolonged immune deficiency after allo-BMT. In the present study, we examined the expression of CD26 as well as the reconstitution of CD26-mediated T-cell costimulation via the CD3 and CD2 pathways at various times in patients aged greater than 18 years after CD6-positive, T-cell depleted allo- BMT. We found that the percentage of CD26- and CD3-positive cells, as well as the levels of expression of both antigens, was lower than in normal controls during the first 4 months after CD6-depleted allo-BMT. Subsequently, the amount of lymphocytes expressing CD3 and CD26 and the quantitative surface expression of CD3 and CD26 were not significantly different in patients and normal controls. Functional studies showed that CD26-mediated T-cell proliferation via the CD3 pathway was considerably improved and almost reached normal levels by 1 year, whereas recovery of CD26-mediated T-cell proliferation via the CD2 pathway was delayed for at least 2 years after CD6-depleted allo-BMT. As CD26 involvement in the regulation of human thymocyte activation is restricted preferentially to the CD3 pathway--unlike its involvement with both CD3 and CD2 pathways of peripheral T cells--our results suggest that the different effects of CD26-mediated costimulation via the CD3 and CD2 pathways after CD6-depleted allo-BMT may be a reflection of peripheral T-cell immaturity in those individuals, similar to that seen in mature medullary thymocytes or cord T lymphocytes. 相似文献