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991.
992.
Assessment of limb muscle and adipose tissue by dual-energy X-ray absorptiometry using magnetic resonance imaging for comparison 总被引:1,自引:0,他引:1
Fuller NJ Hardingham CR Graves M Screaton N Dixon AK Ward LC Elia M 《International journal of obesity (2005)》1999,23(12):1295-1302
OBJECTIVE: To use magnetic resonance imaging (MRI) to validate estimates of muscle and adipose tissue (AT) in lower limb sections obtained by dual-energy X-ray absorptiometry (DXA) modelling. DESIGN: MRI measurements were used as reference for validating limb muscle and AT estimates obtained by DXA models that assume fat-free soft tissue (FFST) comprised mainly muscle: model A accounted for bone hydration only; model B also applied constants for FFST in bone and skin and fat in muscle and AT; model C was as model B but allowing for variable fat in muscle and AT. SUBJECTS: Healthy men (n = 8) and women (n = 8), ages 41-62y; mean (s.d.) body mass indices (BMIs) of 28.6 (5.4) kg/m2 and 25.1 (5.4) kg/m2, respectively. MEASUREMENTS: MRI scans of the legs and whole body DXA scans were analysed for muscle and AT content of thigh (20 cm) and lower leg (10 cm) sections; 24h creatinine excretion was measured. RESULTS: Model A overestimated thigh muscle volume (MRI mean, 2.3 l) substantially (bias 0.36 l), whereas model B underestimated it by only 2% (bias 0.045 l). Lower leg muscle (MRI mean, 0.6 l) was better predicted using model A (bias 0.04 l, 7% overestimate) than model B (bias 0.1 l, 17% underestimate). The 95% limits of agreement were high for these models (thigh, +/-20%; lower leg, +/-47%). Model C predictions were more discrepant than those of model B. There was generally less agreement between MRI and all DXA models for AT. Measurement variability was generally less for DXA measurements of FFST (coefficient of variation 0.7-1.8%) and fat (0.8-3.3%) than model B estimates of muscle (0.5-2.6%) and AT (3.3-6.8%), respectively. Despite strong relationships between them, muscle mass was overestimated by creatinine excretion with highly variable predictability. CONCLUSION: This study has shown the value of DXA models for assessment of muscle and AT in leg sections, but suggests the need to re-evaluate some of the assumptions upon which they are based. 相似文献
993.
Galimberti S Morabito F Guerrini F Palumbo GA Azzará A Martino M Benedetti E Di Raimondo F Petrini M 《British journal of haematology》2003,120(3):405-412
To evaluate the clinical impact of minimal residual disease in multiple myeloma, apheretic products from 51 autotransplanted patients were tested by fluorescent (GeneScan) polymerase chain reaction (PCR). Sixty-nine per cent of harvests were contaminated when evaluated for IgH rearrangement. Forty-six patients responded to transplant, with 52.9% achieving complete response (CR). The clinical response of patients was significantly influenced by the number of re-infused CD34+ cells. Positive PCR results of re-infused harvests were not significantly related to patient outcome. Median overall survival (OS) was 33 months, and a significant advantage for patients transplanted by 12 months from diagnosis was observed. Moreover, OS was longer for patients receiving PCR-negative stem cells, with 72% of patients surviving to 70 months in the group receiving PCR-negative harvests vs 48% in the group transplanted with contaminated precursors (not statistically significant). Ex vivo purging caused a reduction of contamination of up to 3 logs; nevertheless, 80% of purged harvests remained PCR-positive and the purging procedure did not alter response or survival rates. Thus, the failure of a predictive role for this highly sensitive molecular method could be explained by the assumption that in vivo persisting malignant cells are the true source of relapse in MM. 相似文献
994.
Andrés Sánchez-Pernaute Elia Pérez-Aguirre Pablo Talavera Eguizabal Florentino Hernando Trancho Luis Díez-Valladares Antonio Torres García 《Esophagus》2007,4(4):177-179
Transhiatal herniation of the abdominal organs is a rare complication after esophagectomy. Surgical treatment is usually mandatory
because of the high mortality associated with this condition. We present a case of colonic herniation that could contribute
to failure of the esophagogastric anastomosis. Repair of both problems was performed through a right posterior thoracotomy. 相似文献
995.
996.
Michela Faggioni Usman Baber Arash Ehteshami Afshar Gennaro Giustino Samantha Sartori Sabato Sorrentino Philippe G. Steg Giulio G. Stefanini Stephan Windecker Martin B. Leon Gregg W. Stone William Wijns Patrick W. Serruys Marco Valgimigli Edoardo Camenzind Giora Weisz Pieter C. Smits David E. Kandzari Roxana Mehran 《JACC: Cardiovascular Interventions》2018,11(1):68-76
Objectives
This study sought to investigate the effect of different body mass index (BMI) categories on clinical outcomes in female patients treated with percutaneous coronary intervention (PCI) and drug-eluting stents.Background
Patients with higher BMI might, paradoxically, have better long-term clinical outcomes after acute coronary syndrome treated with PCI.Methods
We pooled patient-level data for female participants from 26 randomized trials on PCI with drug-eluting stents. Patients were stratified into underweight (BMI, <18.5), normoweight (BMI, 18.5 to 24.9), overweight (BMI, 25 to 29.9), obese (BMI, 30 to 34.9), or morbidly obese (BMI, ≥35). The primary endpoint was major adverse cardiac events, a composite of death, myocardial infarction, or target lesion revascularization at 3 years.Results
Among 11,557 female patients included in the pooled database, 9,420 were treated with a drug-eluting stent and had BMI data available. Patients with higher BMI were significantly younger and with more cardiovascular risk factors. Only 139 patients were underweight and had significantly higher adjusted rates of cardiac mortality and all-cause mortality than the rest of the population (hazard ratio: 2.20 [1.31 to 3.71] compared with normoweight). There was a significantly lower frequency of unadjusted 3-year all-cause mortality in overweight, obese, and severely obese patients compared with normoweight. However, following multivariable analysis, a trend toward increased risk of death in severely obese patients was observed, describing an inverse “J”-shaped relation between BMI and 3-year mortality. Conversely, the relationship between BMI and other outcomes, such as major adverse cardiac events, was flat for normoweight and higher BMI.Conclusions
The risk of 3-year adjusted cardiac events did not differ across BMI groups, whereas the risk of all-cause mortality compared with normoweight was significantly higher in underweight patients and lower in overweight patients with a trend toward increased risk in the severely obese population. 相似文献997.
Suppression of B-cell development as a result of selective expansion of donor T cells during the minor H antigen graft-versus-host reaction 总被引:1,自引:2,他引:1
A murine model of bone marrow (BM) transplantation in which donor (B10.D2) and recipient (BALB/c) mice were major histocompatibility complex (MHC) (H-2d) and Mls-1 identical, but incompatible at multiple non-MHC minor histocompatibility (H) antigens, and at Mls-2,3 was used to examine regeneration of B-cell development during the minor H antigen graft-versus-host reaction (GVHR). Mice that received T-cell- depleted allogeneic BM regained significant pre-B cells (sIg- 14.8+) in their BM. Mice undergoing GVHR after transplantation with allogeneic BM + T cells had less than 2% pre-B cells in their BM at day 7 and only 12% to 14% pre-B cells at days 21 and 28 compared with greater than 20% pre-B cells in the allogeneic controls. After partial recovery, the pre- B cells in the BM of GVH mice again decreased to less than 3% by day 42. This abnormal pattern of pre-B cell development in mice undergoing GVHR was associated with a reduced response to interleukin-7 (IL-7) in vitro. The delay in B-lineage cell reconstitution in mice with GVHR correlated with the expansion of donor V beta 3+ T cells in both the spleen and BM. BM T cells from mice with GVHR as well as isolated V beta 3+ T cells inhibited IL-7 colony-forming units from normal BM in co-culture assays. This inhibition could be reversed with anti- interferon gamma (IFN gamma) antibody. These data suggest that the delay in appearance and the reduction in proportion and number of pre-B cells observed early during the GVH reaction in this model is caused, in part, by the inhibitory actions of IFN gamma derived from donor V beta 3+ T cells on B-lineage cell development. 相似文献
998.
Vitarelli A Capotosto L Rosato E Salsano F 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2010,37(5):594-597
Cardiovascular involvement is the leading cause of morbidity and death in Churg-Strauss syndrome. Herein, we describe the case of a 47-year-old man with Churg-Strauss syndrome, in whom the use of novel echocardiographic techniques revealed segmental cardiomyopathy. Tissue Doppler and speckle-tracking imaging showed that both longitudinal and radial strain were impaired at the septal level and that the impairment of circumferential strain affected left ventricular torsion. Our case shows that advanced echocardiography with myocardial strain imaging in multiple vectors can identify systolic-diastolic abnormalities in a patient with myocardial infiltration and a normal left ventricular ejection fraction. 相似文献
999.
Carlo L. Balduini Luigi Gugliotta Mario Luppi Luca Laurenti Catherine Klersy Carla Pieresca Gerlando Quintini Francesco Iuliano Rossana Re Pierangelo Spedini Nicola Vianelli Alfonso Zaccaria Enrico Maria Pogliani Roberto Musso Enrico Bobbio Pallavicini Giovanni Quarta Piero Galieni Alberto Fragasso Gianluca Casella Patrizia Noris Edoardo Ascari 《Annals of hematology》2010,89(6):591-596
Therapeutic plasma exchange (PE) is the accepted therapy for thrombotic thrombocytopenic purpura (TTP). Because not all patients achieve remission, other treatment modalities have been used in addition to PE, but no randomized clinical trial evaluated their efficacy. The aim of this multicentric study was to compare the effectiveness of standard- versus high-dose methylprednisolone as an adjunctive treatment to PE in the acute phase of TTP. Sixty patients with idiopathic TTP were randomized to receive methylprednisolone 1 mg/kg/die intravenous or 10 mg/kg/die for 3 days, thereafter, 2.5 mg/kg/die in addition to PE. Both dosages of steroids were well tolerated. At the end of induction therapy (day 23), the percentage of patients failing to achieve complete remission was significantly higher in the standard dose (16 of 30) than in the high-dose group (seven of 30). Also, the number of cases without a good response at day 9 and the number of deaths were higher in the standard-dose arm, but the differences did not reach the statistical significance. Results of present study indicate that the association of PE with high-dose instead of standard-dose steroids reduces the percentage of TTP patients that fail to achieve complete remission. 相似文献
1000.
Fortunato Morabito Giovanna Cutrona Massimo Gentile Marina Fabbi Serena Matis Monica Colombo Daniele Reverberi Mauro Megna Mauro Spriano Vincenzo Callea Ernesto Vigna Edoardo Rossi Eugenio Lucia Gianluca Festini Simonetta Zupo Stefano Molica Antonino Neri Manlio Ferrarini 《British journal of haematology》2010,149(1):160-163