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1.
Cirrhosis is an independent risk factor for the development of osteoporosis. The presence of ascites in patients with cirrhosis may affect the accuracy of bone density measurement in the spine. Twenty cirrhotic patients had bone mineral density (BMD) measurements of the lumbar spine, femoral neck, hip, and total body using dual-energy X-ray absorptiometry (DXA; Lunar Prodigy) before and after large-volume paracentesis. To establish short-term precision of DXA measurement, 28 healthy adults also had duplicate BMD measurements on the same day. After paracentesis (6.4 ± 2.0 L), there was a significant increase in the spine BMD of 4.2% (p = 0.003) and in the total hip BMD of 1.3% (p = 0.002), but there was no change in the femoral neck or total body. No significant differences (p > 0.1) were seen in duplicate BMD measurements at any site among the healthy cohort. Within-patient changes in spine (p = 0.001) and total hip (p = 0.001) BMD measurements were significantly greater in patients with ascites than in the healthy cohort. These changes in BMD measurements were not associated with age, gender, amount of fluid removed, or time interval between measurements. These results suggest that ascites cause a fluid artifact in the soft tissue and bone interface that can falsely lower BMD measurements, particularly in the spine.  相似文献   

2.
A precise assessment of bone mineral density (BMD) and body composition can be performed using dual-energy X-ray absorptiometry (DXA). Values of body composition for males would be useful to evaluate the occurrence of alterations in body composition in a number of diseases. The objectives of this study were to establish BMD and body composition values in healthy men and to analyze age-related changes. BMD and body composition of total body and subareas were determined in 116 healthy men (aged 20–79 yr) using DXA. Comparison between 20–29- and 70–79-yr-old men showed that older subjects were shorter (p < 0.03), and had a higher body mass index (p < 0.01). Fat mass increased (+46.7%; p < 0.001) especially in the trunk. Lean mass (LM) decreased (−9.4%; p < 0.05) mainly in the arms and legs. Bone mineral content (BMC) and BMD decreased (−15.3% [p < 0.001], −6.3% [p < 0.05], respectively). Correlation was observed between BMC and LM (r = 0.7, p < 0.01). Values of BMD and body composition in healthy men were obtained. A relation was observed between bone mass and body composition, suggesting that the age-related decrease in LM may be associated to bone mass loss. Further studies should be conducted to elucidate the role of body composition in the occurrence of osteoporosis in men.  相似文献   

3.
4.
A mildly elevated homocysteine (Hcy) level is a novel and potentially modifiable risk factor for age-related osteoporotic fractures. Elevated Hcy levels can have a nutritional cause, such as inadequate intake of folate, riboflavin, pyridoxine or cobalamin, which serve as cofactors or substrates for the enzymes involved in the Hcy metabolism. We examined the association between intake of Hcy-related B vitamin (riboflavin, pyridoxine, folate and cobalamin) and femoral neck bone mineral density BMD (FN-BMD) and the risk of fracture in a large population-based cohort of elderly Caucasians.

We studied 5304 individuals aged 55 years and over from the Rotterdam Study. Dietary intake of nutrients was obtained from food frequency questionnaires. Incident non-vertebral fractures were recorded during a mean follow-up period of 7.4 years, and vertebral fractures were assessed by X-rays during a mean follow-up period of 6.4 years. We observed a small but significant positive association between dietary pyridoxine (β = 0.09, p = 1 × 10− 8) and riboflavin intake (β = 0.06, p = 0.002) and baseline FN-BMD. In addition, after controlling for gender, age and BMI, pyridoxine intake was inversely correlated to fracture risk. As compared to the three lowest quartiles, individuals in the highest quartile of age- and energy-adjusted dietary pyridoxine intake had a decreased risk of non-vertebral fractures (HR = 0.77, 95% CI = 0.65–0.92, p = 0.005) and of fragility fractures (HR = 0.55, 95% CI = 0.40–0.77, p = 0.0004). Further adjustments for other dietary B vitamins (riboflavin, folate and cobalamin), dietary intake of calcium, vitamin D, vitamin A and vitamin K, protein and energy intake, smoking and BMD did not essentially modify these results.

We conclude that increased dietary riboflavin and pyridoxine intake was associated with higher FN-BMD. Furthermore, we found a reduction in risk of fracture in relation to dietary pyridoxine intake independent of BMD. These findings highlight the importance of considering nutritional factors in epidemiological studies of osteoporosis and fractures.  相似文献   


5.
6.
Yan D  Gurumurthy A  Wright M  Pfeiler TW  Loboa EG  Everett ET 《BONE》2007,41(6):1036-1044
Excessive fluoride (F) can lead to abnormal bone biology. Numerous studies have focused on the anabolic action of F yet little is known regarding any action on osteoclastogenesis. Little is known regarding the influence of an individual's genetic background on the responses of bone cells to F. Four-week old C57BL/6J (B6) and C3H/HeJ (C3H) female mice were treated with NaF in the drinking water (0 ppm, 50 ppm and 100 ppm F ion) for 3 weeks. Bone marrow cells were harvested for osteoclastogenesis and hematopoietic colony-forming cell assays. Sera were analyzed for biochemical and bone markers. Femurs, tibiae, and lumbar vertebrae were subjected to microCT analysis. Tibiae and femurs were subjected to histology and biomechanical testing, respectively. The results demonstrated new actions of F on osteoclastogenesis and hematopoietic cell differentiation. Strain-specific responses were observed. The anabolic action of F was favored in B6 mice exhibiting dose-dependent increases in serum ALP activity (p < 0.001); in proximal tibia trabecular and vertebral BMD (tibia at 50&100 ppm, p = 0.001; vertebrae at 50 and 100 ppm, p = 0.023&0.019, respectively); and decrease in intact PTH and sRANKL (p = 0.045 and p < 0.001, respectively). F treatment in B6 mice also resulted in increased numbers of CFU-GEMM colonies (p = 0.025). Strain-specific accumulations in bone [F] were observed. For C3H mice, dose-dependent increases were observed in osteoclast potential (p < 0.001), in situ trabecular osteoclast number (p = 0.007), hematopoietic colony forming units (CFU-GEMM: p < 0.001, CFU-GM: p = 0.006, CFU-M: p < 0.001), and serum markers for osteoclastogenesis (intact PTH: p = 0.004, RANKL: p = 0.022, TRAP5b: p < 0.001). A concordant decrease in serum OPG (p = 0.005) was also observed. Fluoride treatment had no significant effects on bone morphology, BMD, and serum PYD cross-links in C3H suggesting a lack of significant bone resorption. Mechanical properties were also unaltered in C3H. In conclusion, short term F treatment at physiological levels has strain-specific effects in mice. The expected anabolic effects were observed in B6 and novel actions hallmarked by enhanced osteoclastogenesis shifts in hematopoietic cell differentiation in the C3H strain.  相似文献   

7.
Osteoporosis affects approximately 40–50% of adult patients with β-Thalassemia Major (βTM). Recent data have implicated an altered modulation of the osteoprotegerin (OPG)/receptor activator of NFkB ligand (RANKL) system in the pathogenesis of βTM-osteoporosis. OPG/RANKL system acts downstream from IL-1, IL-6 and TNF- and it may be the final actor mediating the effects of these cytokines on the regulation of both postmenopausal and metabolic bone resorption. However, to date, there are no data on circulating levels of these pro-resorptive cytokines in βTM patients. We investigated the potential relationships among these cytokines, several markers of bone turnover and bone mineral density (BMD) in βTM patients.

IL-1, IL-6 and TNF-, OPG and RANKL serum levels, hemato-urinary bone remodeling markers and bone mineral density (BMD) at L2L4 and femoral neck as well as erythropoietin (EPO), 17β-estradiol, and free-testosterone levels were measured in 30 well treated βTM patients and in 20 healthy subjects, matched for age, sex and BMI with the patients.

βTM patients showed an altered bone turnover, with increased deoxypyridinoline (D-PYR) levels (P < 0.0001), decreased osteocalcin (BGP) concentrations (< 0.0001) and significantly lower lumbar (P = 0.001) and femoral (P < 0.05) BMD values as compared to controls. Circulating levels of IL-1 (P < 0.0001), TNF- (P < 0.0001) and IL-6 (P < 0.05) were all increased in βTM patients as compared with controls. In βTM patients, IL-1 was significantly related with D-PYR (r = 0.5; P < 0.05), RANKL (r = 0.7; P = 0.03) and IL-6 (r = 0.3; P = 0.006); IL-6 was also significantly correlated with D-PYR (r = 0.5; P < 0.05) and EPO levels (r = 0.3; P = 0.03); TNF- showed a negative correlation with L2L4 BMD (r = − 0.4; P < 0.05).

Our data demonstrate, for the first time, an association between increased circulating levels of pro-resorptive cytokines and an altered bone turnover in βTM-patients, suggesting their involvement in the pathogenesis of βTM-osteoporosis.  相似文献   


8.
Quantitative ultrasound (QUS) is a safe, inexpensive, and nonradiation method for bone density assessment. QUS correlates with, and predicts fragility fractures comparable to, dual-energy X-ray absorptiometry (DXA)-derived bone mineral density (BMD) in postmenopausal women. However, its validity in monitoring bone growth in children is not well understood. Two hundred and fifty-eight 10–13 yr pubertal girls and 9 37–43 yr adults without diseases or history of medications known to affect bone metabolism were included in the 2-yr prospective study. Calcaneal broadband ultrasound attenuation (cBUA) was assessed using QUS-2 (Quidel, Santa Clara, CA), speed of sound of tibial shaft (tSOS) using Omnisense (Sunlight Technologies, Israel), apparent volumetric BMD (vBMD) of tibial shaft using peripheral quantitative computed tomography (pQCT; XCT2000, Stratec), and femoral neck (FN) and lumbar spine 2–4 (LS) areal BMD (aBMD) using DXA (Prodigy, GE). Over the 2 yr in girls, FN and LS aBMD showed the largest increases (17 ± 8% and 20 ± 8%, respectively), followed by tibial vBMD and cBUA (10 ± 5% and 9 ± 9%, respectively). There was no apparent change in tSOS (2 ± 3%). The increase in FN and LS aBMD attenuated 48% and 40%, respectively, after adjustment of the change in body size. The change of cBUA correlated significantly with change in tibial vBMD and FN and LS aBMD (r = 0.24–0.40). At the matched location, tSOS correlated only with cortical vBMD, not with cortical thickness, apparent vBMD, or bone size. The long-term reproducibility, assessed using the concordance correlation coefficient of young adults' pre-post measurements, was substantially lower in tSOS than cBUA, tibial vBMD, FN, and LS aBMD (0.65 vs 0.97, 0.95, 0.98, and 0.96; p < 0.05). The transverse transmission method-derived calcaneal BUA, but not the axial transmission method-derived SOS, is comparable to DXA and pQCT for monitoring bone densitometric change in pubertal girls. The role of QUS in fracture-risk prediction in children and adolescents needs further investigation.  相似文献   

9.
Homocysteine (Hcy) and C-reactive protein (CRP) are novel risk factors for osteoporosis. The purpose of this analysis was to determine the relationship of Hcy and CRP to volumetric trabecular bone, but also to assess their relationship to areal composite bone in healthy postmenopausal women (N = 184). We used peripheral quantitative computed tomography to assess volumetric bone at the distal tibia and dual-energy X-ray absorptiometry to assess areal composite bone at the proximal femur and lumbar spine. Multiple regression revealed that 22% of the variability in trabecular bone mineral content (F = 9.59, p ≤ 0.0001) was accounted for by weight (12.4%; p ≤ 0.0001), hemoglobin (5.5%; p = 0.0006), uric acid (4.2%; p = 0.003), and blood glucose (1.5%; p = 0.07). Multiple regression revealed that 5.4% of the variability in trabecular bone mineral density (F = 3.36; p = 0.020) was accounted for by hemoglobin (4.2%; p = 0.006) and Hcy (1.5%; not significant, p = 0.10). Total Hcy and CRP were not significantly related to trabecular bone, perhaps because these were nonosteoporotic women. However, our results suggested a weak but negative relationship between Hcy and trabecular bone. Further investigation is needed to examine the relationship of Hcy as an endogenous bioactive molecule to trabecular bone loss in early postmenopausal women and the response of trabecular bone to dietary intervention.  相似文献   

10.
Objective: To identify factors that affect operative mortality and morbidity and long-term survival after completion pneumonectomy. Methods: We retrospectively reviewed the charts of consecutive patients who underwent completion pneumonectomy at our cardiothoracic surgery department from January 1996 to December 2005. Results: We identified 69 patients, who accounted for 17.8% of all pneumonectomies during the study period; 22 had benign disease and 47 malignant disease (second primary lung cancer, n = 19; local recurrence, n = 17; or metastasis, n = 11). There were 50 males and 19 females with a mean age of 60 years (range, 29–80 years). Postoperative mortality was 12% and postoperative morbidity 41%. Factors associated with postoperative mortality included obesity (p = 0.005), coronary artery disease (p = 0.03), removal of the right lung (p = 0.02), advanced age (p = 0.02), and renal failure (p < 0.0001). Preoperative renal failure was the only significant risk factor for mortality by multivariate analysis (p = 0.036). Bronchopleural fistula developed in seven patients (10%), with risk factors being removal of the right lung (p = 0.04) and mechanical stump closure (p = 0.03). Overall survival was 65% after 3 years and 46% after 5 years. Long-term survival was not affected by the reason for completion pneumonectomy. Conclusion: Although long-term survival was acceptable, postoperative mortality and morbidity rates remained high, confirming the reputation of completion pneumonectomy as a challenging procedure. Significant comorbidities and removal of the right lung were the main risk factors for postoperative mortality. Improved patient selection and better management of preoperative renal failure may improve the postoperative outcomes of this procedure, which offers a chance for prolonged survival.  相似文献   

11.
Bone loss is one of the most common complications after solid-organ transplantation, but it is frequently under-diagnosed. Our purpose was to evaluate quantitative ultrasound of calcaneus (QUS) in comparison with dual-energy X-ray absorptiometry (DXA) to identify transplant recipients with osteoporosis. We have cross-sectionally evaluated 140 transplant recipients (85 liver and 55 cardiac transplantations; mean age: 53.6 years, time since transplantation: 67.9 months). Devices used were Hologic 4500 QDR for DXA measurements and Sahara Clinical Sonometer (Hologic Inc, Bedford, MA) for calcaneal QUS. Quantitative ultrasound index (QUI) was calculated from speed of sound (m/s) and broadband ultrasonic attenuation (dB/MHz). QUI T-score and bone mineral density (BMD) T-score (spine and hip) were obtained from Spanish normative data. According to World Health Organization criteria, defined either at lumbar spine or femoral neck, 61% of the females had osteopenia and 32% had osteoporosis, whereas 52% of the males had osteopenia and 11% had osteoporosis. Calcaneal QUS parameters (speed of sound, broadband ultrasonic attenuation, and QUI) were positively correlated with lumbar and femoral BMD (p < 0.001). In receiver operator characteristic analysis, a T-score QUI ≤ − 1.4 standard deviation (SD) had 68% sensitivity and 72% specificity for osteoporosis diagnosis by DXA criteria. However, to obtain maximal sensitivity (5% of false-negative), QUI T-score cutoff should be − 0.6 SD, but specificity drops to 42%. In conclusion, a positive correlation exists between lumbar and femoral BMD and QUS parameters in long-term liver or cardiac transplant recipients. QUS could be recommended for screening of osteoporosis in long-term transplanted patients.  相似文献   

12.
Background: Non-small cell lung cancer (NSCLC) has a poor prognosis even for early stages of the disease (stage I and II). We studied the prognostic value of PET FDG in patients with completely resected stage I and II NSCLC. Methods: Retrospective study of 96 patients with NSCLC whose staging included 18F-FDG PET (fluoro deoxy glucose positron emission tomography). Histopathological stage was either stage I (75) or stage II (n = 21). FDG uptake was measured as maximal standardized uptake value for body weight (SUVmax). Mean follow-up was 45 ± 30 months (1–142 months). Overall and cancer-free survival rates were recorded. Results: SUVmax were higher for stage II than for stage I (10.5 ± 4.5 vs 8.5 ± 5, p = 0.04). Mean tumor volumes were equivalent for both stages (33 cm3, p = 0.18), excluding a partial volume effect. The median SUVmax in the whole study population was 7.8. The median survival was significantly longer in patients with a lower (SUVmax ≤ 7.8) FDG uptake (127 months vs 69 months, p = 0.001). For stage I tumors (n = 75), high FDG uptake was significantly associated with reduced median survival: 127 months if SUVmax ≤ 7.8 and 69 months if SUVmax > 7.8 (p = 0.001). For stage II tumors (n = 21), no statistical difference was observed: 72 months vs 40 months for SUVmax ≤ 7.8 and for SUVmax > 7.8, respectively (p = 0.11), although there was a clear trend towards reduced survival for highly metabolic tumors. Disease-free survival was also significantly better for lower metabolic tumors: 96.1 months vs 87.7 months (p = 0.01). Conclusion: High FDG uptake is associated with reduced overall survival and disease-free survival of patients with completely resected stage I–II NSCLC. Whether patients with highly metabolic tumors should undergo a closer postoperative surveillance or adjuvant chemotherapy has to be addressed in a properly designed prospective trial.  相似文献   

13.
Assessment of Femoral Neck Strength by 3-Dimensional X-ray Absorptiometry   总被引:1,自引:0,他引:1  
Hip fractures due to osteoporosis are accompanied with increased mortality and morbidity. Bone mineral density (BMD [g/cm2]) measured by dual-energy X-ray absorptiometry (DXA) is the most important risk factor. However, an overlap exists between results of fractured and nonfractured populations. Macro-architectural parameters of the femur are independent risk factors of fracture. They have been evaluated in two dimensions using X-ray films or DXA scans; therefore, they are highly dependent on patient positioning and interindividual anatomical variations. To overcome this problem, we have previously shown the possibility to reconstruct human femurs using two perpendicular DXA scans and to calculate 3-dimensional (3D) geometric parameters from these reconstructions by a method called 3-dimensional X-ray absorptiometry (3D-XA). The aim of this article is to assess whether the combination of areal BMD and 3D geometric parameters calculated from 3D-XA improves failure load prediction of human proximal femurs in stance phase configuration. Twelve femurs (11 women, 1 man; aged 88 ± 9 yr; range: 72–103 yr) were included in this study. The BMD was measured using a Hologic Delphi-W device (Hologic, Waltham, MA) and 3D reconstruction of the femurs was done using two perpendicular DXA scans as previously published. The calculated 3D geometric parameters included femoral neck axis length (FNAL), mid-femoral neck cross-sectional area (mid-FN CSA), neck shaft angle (NSA), and femoral head diameter (FHD). Mechanical testing was performed using stance phase configuration, which resulted in subcapital fractures. The FHD was correlated to mid-FN CSA and FNAL (r = 0.68 and 0.76, respectively; p < 0.001). Failure load was correlated to age, FHD, NSA, and BMD measurements. Multiple regression analysis showed that femoral neck BMD, FHD, and mid-FN CSA gave the best statistical model for failure load prediction (r2 = 0.84; p < 0.002). This is the first study suggesting that combining areal BMD to 3D geometric parameters obtained by 3D-XA improve failure load prediction in human femurs.  相似文献   

14.
Objective: Cerebrovascular accidents (CVA) are devastating complications after coronary artery bypass grafting (CABG). The reported incidence of neurological complications after conventional CABG (CCABG) is 3–6%. Off-pump coronary bypass grafting (OPCAB) has been associated in recent studies to a decreased morbidity and risk of perioperative stroke. Nevertheless, uncertainty still surrounds the relative benefits of OPCAB. We investigated whether, in our experience, OPCAB was associated with lower neurological morbidity than conventional CABG approach. Methods: Eight thousand and two patients underwent isolated CABG at our institution between January 1998 and January 2005. OPCAB operation was performed on 1415 patients. Data were prospectively collected. A multiple logistic regression analysis was used to evaluate the influence of the two different surgical techniques on the neurological outcomes. Results: Patients in the OPCAB group were significantly older (66.2 vs 63.5%, p < 0.0001), had a higher incidence of renal injury (5.4 vs 2.4%, p < 0.0001), and were more redo interventions (6.95 vs 1.53%, p < 0.0001). The CCABG patients were more urgent at operation (5.46 vs 3.26, p = 0.0007), were less hypertensive (57.6 vs 63% of the patients, p = 0.0003) more diabetics (22 vs 20.6%, NS), and had an ejection fraction less than 0.40 (10.4 vs 9.6%, NS). CVA incidence was similar in both groups (Type I outcome: OPCAB = 0.70% vs CCABG = 0.68%, p = 0.91; Type II outcome OPCAB = 0.70% vs CCABG = 0.83%, p = 0.63). Conclusions: In our experience patients undergoing CCABG were not exposed to a grater risk of neurological adverse events when compared to OPCAB patients.  相似文献   

15.
The aim of this study was to establish the contribution of human immunodeficiency virus (HIV) itself on body composition changes evaluated by dual-energy X-ray absorptiometry (DXA). Body composition evaluated by DXA in 90 HIV never treated men, without comorbidity, or current or past opportunistic infections were compared with 241 healthy volunteers. The mean duration of seropositivity from HIV diagnosis was 41 ± 62 mo, mean CD4 and viral load at the time of DXA were 402/mm3 ± 263 (control values 500–1200/mm3) and 4.2 log copies/mL ± 1.3. Mean age (41 vs 39 yr, respectively, for HIV never treated patients and controls) and mean height (174.5 vs 176 cm) were not different, but mean weight was lower among HIV never treated patients (69.8 vs 78.7 kg). Mean total body bone mineral density (BMD) of naive HIV-infected patients was lower than that of controls (1.20 vs 1.23 g/cm2, p = 0.01) but not after adjustment on age, height, lean mass (LM), and fat mass ratio (FMR = % trunk fat mass/% lower limb fat mass). Fat mass (13.2 vs 16.5 kg, p < 0.0001) and LM (53.5 vs 59 kg, p < 0.0001) of naive HIV-infected patients were lower whatever the adjustment variables. The FMR was lower in naive HIV-infected men (1.0 vs 1.3, p < 0.0001) because of a decreased trunk fat mass. After adjustment on age, height, LM, and fat mass, the lower limbs fat mass percentage was higher in HIV-infected men. The profile of naïve HIV-infected patients displayed low lean and fat masses, and a fat mass repartition characterized by a predominant loss in the trunk. Those alterations may result from the catabolic effect of the chronic HIV infection.  相似文献   

16.
It is known that different skeletal sites have different peak bone mass at different times and lose bone at different rates. The purpose of the study was to assess bone mineral density (BMD) in healthy female student population (N = 220), aged 18–25 yr and to analyze whether young women of that age have already started to lose the bone mass at the trabecular and cortical parts of skeleton. The influence of dietary intake and physical activity on their bone mass was also assessed. BMD was measured, using dual-energy X-ray absorptiometry technique, in spine, proximal femur, and distal third of the radius and in total body. Significant negative correlation between age and bone mass was found in all skeletal regions (p < 0.05 spine; p < 0.0001 total femur; and p < 0.01 total body) except in cortical part of the radius. Peak bone mass in young Croatian women was achieved before the age of 20, but later in the long-bone cortical skeleton, where BMD continued to increase after mid-20s. The BMD values are comparable with those from National Health and Nutrition Examination Survey study, except for the cortical part of the radius, where it is significantly lower. Body weight and physical activity were the most significant positive predictors of bone density in all measured sites.  相似文献   

17.
A three decade analysis of factors affecting burn mortality in the elderly   总被引:1,自引:0,他引:1  
This study's objective was to identify variables that affect the mortality of elderly burn patients and to assess their changes over time. A retrospective review was conducted on all patients 75 or older (n = 201) admitted to a university-based burn center between 1972 and 2000. Variables examined were age, sex, TBSA, ABSI, inhalation injury, timing from burn to operative intervention, the number of surgical procedures, the number of pre-morbid conditions, and mortality. There were 95 fatalities. TBSA strongly correlated with mortality (p < 0.0001). Adjusting for TBSA and inhalation injury, mortality significantly decreased (p = 0.04, odds ratio = 0.58). Mortality significantly increased with inhalation injury (p < 0.01). Fatality risk increased by 400% with inhalation injury. Absence of inhalation injury was not significant with respect to mortality in the 1970s, however there was a significant decrease (p = 0.02) in mortality without an inhalation injury in the 1980s and 1990s. ABSI was strongly predictive of mortality (p < 0.0001). On average there was a 200% increase in mortality per unit increase of ABSI. The elderly are 58% less likely to die from burns now as compared to the 1970s. Although mortality rose with increasing TBSA equally in each decade, the absolute risk of mortality decreased over time. This data suggests major strides have been made in burn care, however similar success has not been achieved with inhalation injuries.  相似文献   

18.
Objective: During cardiopulmonary bypass (CPB), systemic coagulation is believed to become activated by blood contact with the extracorporeal circuit and by retransfusion of pericardial blood. To which extent retransfusion activates systemic coagulation, however, is unknown. We investigated to which extent retransfusion of pericardial blood triggers systemic coagulation during CPB. Methods: Thirteen patients undergoing elective coronary artery bypass grafting surgery were included. Pericardial blood was retransfused into nine patients and retained in four patients. Systemic samples were collected before, during and after CPB, and pericardial samples before retransfusion. Levels of prothrombin fragment F1+2 (ELISA), microparticles (flow cytometry) and non-cell bound (soluble) tissue factor (sTF; ELISA) were determined. Results: Compared to systemic blood, pericardial blood contained elevated levels of F1+2, microparticles and sTF. During CPB, systemic levels of F1+2 increased from 0.28 (0.25–0.37; median, interquartile range) to 1.10 (0.49–1.55) nmol/l (p = 0.001). This observed increase was similar to the estimated (calculated) increase (p = 0.424), and differed significantly between retransfused and non-retransfused patients (1.12 nmol/l vs 0.02 nmol/l, p = 0.001). Also, the observed systemic increases of platelet- and erythrocyte-derived microparticles and sTF were in line with predicted increases (p = 0.868, p = 0.778 and p = 0.205, respectively). Before neutralization of heparin, microparticles and other coagulant phospholipids decreased from 464 μg/ml (287–701) to 163 μg/ml (121–389) in retransfused patients (p = 0.001), indicating rapid clearance after retransfusion. Conclusion: Retransfusion of pericardial blood does not activate systemic coagulation under heparinization. The observed increases in systemic levels of F1+2, microparticles and sTF during CPB are explained by dilution of retransfused pericardial blood.  相似文献   

19.
Background: Congenital subaortic stenosis entails a lesion spectrum, ranging from an isolated obstructive membrane, to complex tunnel narrowing of the left outflow associated with other cardiac defects. We review our experience with this anomaly, and analyze risk factors leading to restenosis requiring reoperation. Methods: From 1994 to 2006, 58 children (median age 4.3 years, range 7 days–13.7 years) underwent primary relief of subaortic stenosis. Patients were divided into simple lesions (n = 43) or complex stenosis (n = 15) associated with other major cardiac defects. Age, pre- and postoperative gradient over the left outflow, associated aortic or mitral valve insufficiency, chromosomal anomalies, arteria lusoria, and operative technique (membrane resection (22) vs associated myectomy (34) vs Konno (2)) were analyzed as risk factors for reoperation (Kaplan–Meier, Cox regression). Results: There was no operative mortality. Median follow-up spanned 2.7 years (range 0.1–10), with one late death at 4 months. Reoperation was required for recurrent stenosis in 11 patients (19%) at 2.6 years (range 0.3–7.5) after initial surgery. Risk factors for reoperation included complex subaortic stenosis (p = 0.003), younger age (p = 0.012), postoperative residual gradient (p = 0.019), and the presence of an arteria lusoria (p = 0.014). For simple lesions, no variable achieved significance for stenosis recurrence. Conclusions: Surgical relief of congenital subaortic stenosis, even with complex defects, yields excellent results. Reoperation is not infrequent, and should be anticipated with younger age at operation, complex defects, residual postoperative gradient, and an arteria lusoria. Myectomy concomitant to membrane resection, even in simple lesions, does not provide enhanced freedom from reoperation, and should be tailored to anatomic findings.  相似文献   

20.
Although children with juvenile idiopathic arthritis (JIA) are at risk for vertebral fractures, recent conventional posterior-anterior (PA) spine dual-energy X-ray absorptiometry studies reported minimal areal bone mineral density (aBMD, g/cm2) deficits. Width-adjusted BMD (WA-BMD, g/cm3) represents the bone mineral content (BMC) from the lateral projection, excluding the dense cortical spinous processes, divided by the estimated vertebral body volume based on paired PA-lateral bone dimensions. Therefore, WA-BMD may be more sensitive to JIA effects on the predominantly trabecular vertebral body. Age- and sex-specific Z-scores for spine aBMD and WA-BMD were generated in 84 JIA subjects compared with healthy controls, aged 5–21 yr. JIA was associated with lower mean WA-BMD Z-scores (−0.78, 95% CI: −1.03, −0.53; p < 0.001) and aBMD Z-scores (−0.26, 95% CI: −0.49, −0.02; p < 0.05), compared with controls. WA-BMD Z-scores were significantly lower than aBMD Z-scores in JIA (p < 0.001). A significant JIA by age interaction (p < 0.001) indicated that the magnitude of the difference between WA-BMD and aBMD Z-scores was greater in younger subjects. In conclusion, WA-BMD may be more sensitive to disease effects in children because it selectively measures the trabecular-rich vertebral body and is independent of growth-related changes in BMC of the dense spinous processes.  相似文献   

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