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The influence of uremic serum on 125I-fibrinogen binding by normal blood platelets after induction with adenosine diphosphate was evaluated. The study was performed on 12 hemodialyzed uremic patients. The control group included 12 healthy subjects. It has been demonstrated that the uremic serum from the patients before hemodialysis significantly augmented fibrinogen binding by normal blood platelets (33.8 +/- 11.8%) in comparison with control subjects (14.4 +/- 8.9%). After hemodialysis, fibrinogen binding was comparable with the control group (14.9 +/- 10.1%). Uremic toxins removable during hemodialysis are probably responsible for the potentiation of 125I-fibrinogen binding by platelets.  相似文献   
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Background

Ambient coarse, fine, and ultrafine particles have been associated with mortality and morbidity. Few studies have compared how various particle size fractions affect systemic biomarkers.

Objectives

We examined changes of blood and urinary biomarkers following exposures to three particle sizes.

Methods

Fifty healthy nonsmoking volunteers, mean age of 28 years, were exposed to coarse (2.5–10 μm; mean, 213 μg/m3) and fine (0.15–2.5 μm; mean, 238 μg/m3) concentrated ambient particles (CAPs), and filtered ambient and/or medical air. Twenty-five participants were exposed to ultrafine CAP (< 0.3 μm; mean, 136 μg/m3) and filtered medical air. Exposures lasted 130 min, separated by ≥ 2 weeks. Blood/urine samples were collected preexposure and 1 hr and 21 hr postexposure to determine blood interleukin-6 and C-reactive protein (inflammation), endothelin-1 and vascular endothelial growth factor (VEGF; vascular mediators), and malondialdehyde (lipid peroxidation); as well as urinary VEGF, 8-hydroxy-deoxy-guanosine (DNA oxidation), and malondialdehyde. Mixed-model regressions assessed pre- and postexposure differences.

Results

One hour postexposure, for every 100-μg/m3 increase, coarse CAP was associated with increased blood VEGF (2.41 pg/mL; 95% CI: 0.41, 4.40) in models adjusted for O3, fine CAP with increased urinary malondialdehyde in single- (0.31 nmol/mg creatinine; 95% CI: 0.02, 0.60) and two-pollutant models, and ultrafine CAP with increased urinary 8-hydroxydeoxyguanosine in single- (0.69 ng/mg creatinine; 95% CI: 0.09, 1.29) and two-pollutant models, lasting < 21 hr. Endotoxin was significantly associated with biomarker changes similar to those found with CAPs.

Conclusions

Ambient particles with various sizes/constituents may influence systemic biomarkers differently. Endotoxin in ambient particles may contribute to vascular mediator changes and oxidative stress.

Citation

Liu L, Urch B, Poon R, Szyszkowicz M, Speck M, Gold DR, Wheeler AJ, Scott JA, Brook JR, Thorne PS, Silverman FS. 2015. Effects of ambient coarse, fine, and ultrafine particles and their biological constituents on systemic biomarkers: a controlled human exposure study. Environ Health Perspect 123:534–540; http://dx.doi.org/10.1289/ehp.1408387  相似文献   
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The incidence of non-specific reactions with E. multilocularis antigen in patients with liver malignancies, and the risk of a supradiagnosis of alveolar echinococcosis (AE) in space-occupying lesions in the liver due to neoplastic proliferative diseases were studied. Analysis of specific IgG serum antibody against Em2plus antigenic complex was performed in 11 AE patients in comparison to 76 individuals with malignant neoplasms of abdominal or extra-hepatic location, including some patients with primary hepatocellular cancer or distant metastases to liver, and 42 patients with benign hepatic lesions. Only one false borderline result was reported in a case with colorectal cancer, and dissemination to liver. Low risk of false positive results with E. multilocularis-specific Em2plus antigen in patients with liver malignancies makes the test valuable for practical reasons in a differential diagnosis of irregular tumor masses visualized by imaging techniques.  相似文献   
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A considerable proportion of high grade cervical intraepithelial lesions (CIN2/3) are known to resolve on their own especially among young women. However, since reliable prognostic markers are still lacking, the diagnosis “CIN3” is still an indication for surgery which may result in overtreatment. It is conceivable that a combination of different, ideally independent molecular markers may provide more reliable results. In the present cross‐sectional study two established triage markers, 3q26 amplification and a methylation signature, were evaluated in an age‐dependent manner. The patient cohort comprised 60 patients with histologically confirmed CIN2/3 in two equally sized age groups (<30 years, ≥30 years). Cervical scrapes were analyzed by interphase fluorescence in situ hybridization for 3q26 amplification and methylation specific PCR (GynTect®) for six different genome regions. Both assays showed a significantly different pattern of test outcome independent of age (P = .001). Moreover, the combination of both assays differed significantly for double positive and double negative cases when comparing the two age groups: In patients <30 years there were clearly less cases with positive methylation signature and amplification of 3q26 as in women ≥30 years (23% vs 63%, Bonferroni adjusted P = .016). Of particular interest is the finding that double negative results were exclusive for the young age group (0% vs 27%, Bonferroni adjusted P = .020). Since regression of CIN2/3 characteristically occurs among young women it is tempting to speculate that a double negative test result could be prognostic for regression of CIN2/3. This will have to be investigated further in a prospective longitudinal intervention study.  相似文献   
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Abstract: Magnetic resonance‐mammography is regarded as the most sensitive diagnostic modality in the detection of breast cancer. It uses the tumour neoangiogenesis to depict lesions after intravenous contrast agent injection. It is said, that for tumours exceeding a diameter of three millimetres contrast agent enhancement is mandatory. In our case report we describe a rare tumour growth condition. We observed a large invasive carcinoma (18 millimetres diameter) without contrast enhancement in breast MRI due to an almost missing tumour neoangiogenesis. The cancer had a low cellularity and a strong desmoplastic reaction.  相似文献   
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