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21.
22.

Background:

The overwhelming majority of patients with stress cardiomyopathy (SC) are postmenopausal women, suggesting an important pathophysiologic role of the female sex hormones. Preliminary data suggest that myocardial stunning might be provoked by estrogen deficiency.

Hypothesis:

We hypothesized that, compared with age‐ and gender‐matched patients with myocardial infarction (MI) or patients with normal coronary arteries, patients with SC would exhibit altered levels of sex hormones. Furthermore, we aimed to describe the clinical course and the pattern of sex hormones of the SC patients during long‐term follow‐up.

Methods:

Blood samples obtained on hospital admission were analyzed for estradiol (E2), progesterone (P), luteinizing hormone (LH), and follicle‐stimulating hormone (FSH) in women with SC (n = 17), age‐matched women with acute MI (n = 16), and women with normal coronary arteries (n = 15). Six years after the initial event, SC patients underwent a clinical and echocardiographic follow‐up and reassessment of sex hormones.

Results:

Estrogen concentrations at hospital admission were significantly higher in the SC group compared with the MI and the control groups, with no difference in P, FSH, and LH concentrations. Follow‐up E2 after 6 years in SC patients was lower than during the acute SC episode. Follow‐up P in these patients was lower than P in the MI and control groups during the acute event, with a similar trend for E2. After a median follow‐up of 6.4 years, 1 sudden cardiac death occurred and 2 patients suffered from SC recurrence.

Conclusions:

During the acute event, E2 concentrations are elevated in postmenopausal SC patients compared with women with acute MI or with normal coronary arteries. The higher E2 concentrations might have exerted atheroprotective effects and thus diverted the stress response to SC rather than MI. Recurrence and/or sudden cardiac death remains a potential risk of SC. Clin. Cardiol. 2012 DOI: 10.1002/clc.21986 Roman Brenner, MD, and Daniel Weilenmann, MD, contributed equally to this work and should be considered first authors. The authors have no funding, financial relationships, or conflicts of interest to disclose.  相似文献   
23.

Purpose

The aim of this study was to quantify the amount of bone morphogenic protein 7 (BMP-7) in bone samples in different storage and treatment conditions used in bone banks and thereby evaluate the benefit of this test as a routine measure before bone grafting.

Methods

Fresh as well as frozen bone chips, each with and without antibiotic impregnation, were screened for their BMP-7 content. Human bone chips were produced from femoral heads of two female donors who had undergone total hip replacement surgery. The amount of BMP-7 was detected using a commercially available enzyme-linked immunosorbent assay (ELISA) test.

Results

There were no significant differences between groups in samples obtained from the first femoral head. Bone-chip samples derived from the second femoral head showed significant differences between groups. The actual amount of these differences was small and most likely biologically irrelevant. It is important to note that there was a significant difference between groups when comparing both femoral heads, reflecting donor-to-donor variability.

Conclusion

ELISA testing for BMP-7 as a qualitative measurement of bone grafts should be considered a routine quality-control test for bone banks.  相似文献   
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ABSTRACT— Immunoelectrophoresis was performed in 31 of 272 patients with chronic active hepatitis (CAH) because of an M-spike component (seven patients, 2.6%) or hypergammaglobulinemia (24 patients) revealing a monoclonal gammopathy (MG) in 11 patients. In addition, 50 randomly selected patients with CAH and no evidence for an M-spike component were tested by immunoelectrophoresis. In 13 patients (26%), an MG was found. The mean age of the 24 patients with MG was 57.4 years (range: 23–76). HBsAg was present in nine patients (37.5%), no HBV-marker was detected in ten patients (41.7%). The immunoglobulin class of MG was IgG in ten patients (41.7%), IgA in one patient (4.2%) and IgM in 11 patients (45.8%). In two patients, Bence Jones protein was found in either serum or urine. In only one patient was the MG associated with multiple myeloma, whereas none of the other 23 patients developed a malignant lymphoproliferative disease within the median observation period of 6 years. We conclude that there is an unexpectedly high prevalence of benign MG in patients with CAH.  相似文献   
26.
Patients with diabetes mellitus (DM) have more severe coronary artery disease and a two‐ to fourfold higher risk for myocardial infarction and death as compared to patients without DM. In this study, we analyzed coronary anatomy, left ventricular ejection fraction, and cardiac risk factors in patients with DM referred for coronary angiography and compared them with findings in nondiabetic patients. Coronary anatomy was assessed in a total of 6,234 patients and left ventricular ejection fraction in a subset of 4,767 (76.5%) patients. Diabetic patients (n = 641) were older (60.8 ± 9.6 vs. 58.5 ± 10.5 years; P < 0.0001) and had higher rates of hypertension (65% vs. 47%; P < 0.0001). Three‐vessel disease (DM 44.7% vs. no DM 25.4%; P < 0.0001) and reduced left ventricular ejection fraction (DM 58.4% ± 15.2 vs. no DM 63.9% ± 13.2; P < 0.0001) were significantly associated with DM. After adjustment for age and other vascular risk factors, the presence of DM was associated with a higher atherosclerotic burden. We conclude that advanced coronary heart disease and left ventricular dysfunction are highly prevalent in diabetic patients, independent of age and other cardiovascular risk factors. Thus, cardiac assessment in diabetic patients should, in addition to optimal diabetic control, involve screening for left ventricular dysfunction. Cathet Cardiovasc Intervent 2004;62:432–468. © 2004 Wiley‐Liss, Inc.  相似文献   
27.
28.
H-ficolin (Hakata antigen, ficolin-3) activates the lectin pathway of complement similar to mannose-binding lectin. However, its impact on susceptibility to infection is currently unknown. This study investigated whether the serum concentration of H-ficolin at diagnosis is associated with fever and neutropenia (FN) in paediatric cancer patients. H-ficolin was measured by time-resolved immunofluorometric assay in serum taken at cancer diagnosis from 94 children treated with chemotherapy. The association of FN episodes with H-ficolin serum concentration was analysed by multivariate Poisson regression. Median concentration of H-ficolin in serum was 26 mg/l (range 6–83). Seven (7%) children had low H-ficolin (< 14 mg/l). During a cumulative chemotherapy exposure time of 82 years, 177 FN episodes were recorded, 35 (20%) of them with bacteraemia. Children with low H-ficolin had a significantly increased risk to develop FN [relative risk (RR) 2·24; 95% confidence interval (CI) 1·38–3·65; P = 0·004], resulting in prolonged duration of hospitalization and of intravenous anti-microbial therapy. Bacteraemia occurred more frequently in children with low H-ficolin (RR 2·82; CI 1·02–7·76; P = 0·045). In conclusion, low concentration of H-ficolin was associated with an increased risk of FN, particularly FN with bacteraemia, in children treated with chemotherapy for cancer. Low H-ficolin thus represents a novel risk factor for chemotherapy-related infections.  相似文献   
29.
Background/Aims: Obesity is a known risk factor for severe acute pancreatitis (AP). Since alcoholic chronic pancreatitis (ACP) is closely linked to alcoholic AP, overweight before disease onset might impact on incidence and outcome of ACP, and represent an additional riskfactor for ACP. This issue has not been investigated, despite discussions on the ‘hypercaloric-high-fat’ hypothesis as an additional riskfactor for ACP for many years. Methods: The study is part of our prospective long-term study of a large, mixed, medical/surgical series of ACP patients. All cooperative patients were studied according to a protocol regarding clinical symptoms, physical status, routine laboratory tests, pancreatic function and pancreatic morphology (e.g. calcification) at yearly followups. Our study includes 227 ACP patients with recorded body mass index (BMI) before disease onset followed up on average for 18 years from chronic pancreatitis (CP) onset. Results: Males predominated (89.9%), age at onset averaged at 36 years, and exocrine insufficiency (97.4%) and calcification (88.1%) developed in virtually all patients. Surgery for B-type pain was performed in 57.7%, and death occurred in 62.8%. Overweight before disease onset was found in 54.2% (obesity in 15.0%) compared to 37.7% (3.1%) from a contemporary male control population. The highest BMI before disease onset did not impact on some major variables of ACP such as gender, age, progression of exocrine insufficiency, diabetes and calcification, and mortality from CP, except for a delayed progression rate of ACP indices in the surgical series. Conclusion: Overweight before disease onset appears to be another risk factor for ACP, supporting the ‘hypercaloric-high-fat’ hypothesis.  相似文献   
30.

Summary   

We evaluated the effects of parathyroid hormone (PTH), pamidronate, or renutrition on osseointegration of titanium implants in the proximal tibia of rats subject to prolonged low-protein diets. PTH improved mechanical fixation, microarchitecture, and increased pull-out strength. Pamidronate or renutrition had lesser effects. PTH can thus improve implant osseointegration in protein-malnourished rats.  相似文献   
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