The Effect of Zearalenone on Growth Rate,Organ Weight and Muscle Fibre Composition in Growing Rats

Abstract: The effect of prolonged zearalenone administration to growing rats on body and organ weight as well as on muscle fibre composition has been studied. Two muscles, M. longissimus dorsi and M. vastus lateralis. were selected for fibre analyses, and the different fibre types were identified by histochemical staining. Zearalenone caused retarded growth and reduced carcass weight in both sexes. With low daily doses female growth was retarded more than male growth, with higher doses the effect was the opposite. The most evident effects of zearalenone treatment on organ weight were enlargement of the liver in both sexes and of adrenal glands and the spleen in males. No effects were found on heart, kidney, testes or uterus. No significant changes of fibre number or diameter occurred in male rats after prolonged zearalenone feeding. In female rats, however, there was a 40% decrease in the number of αR fibres in vastus and a corresponding increase of αW fibres. Simultaneously the αR fibre size increased with 25%. No significant changes could be found in the activity of two enzymes in vastus, cytochrome oxidase and lactate dehydrogenase, as a consequence of the zearalenone treatment.     

Detecting components of hearing aid fitting using a self-assessment-inventory

The evaluation of hearing-aid fitting includes numerous assessments such as electro- and psychoacoustic tests. The subjective estimation of the hearing aid user can be elicited with self-assessment inventories encompassing various parameters, e.g., benefit, satisfaction and usage. A questionnaire comprising 11 domains (disability, handicap, frequency and significance of the listening situation, importance of the hearing aid, expectation, demand, aided performance, benefit, satisfaction and usage) within three different conditions (speech in quiet and in noise and listening to sounds) was used to detect components underlying hearing aid fitting. The data show a three-factor structure (situation-, restriction- and aid-related variables) independent from the conditions. Usage depends on all of the three factors. Disability and handicap reveal the highest values for speech in noise, whereas the aid-related factor shows the lowest values for this condition. Global satisfaction with the hearing aid is significantly correlated with the aid-related factor, but independent from the restriction of hearing. The aid-related factor is positively influenced by the amount of social activity because more active persons report higher benefit and satisfaction for all listening conditions. Age does not exhibit a significant relationship to one of the components. Basically, all correlation coefficients are only intermediate, revealing that inter-individual differences of the patients are rather high. The data indicate that extra-audiological factors might also play an important role in the success of hearing aid fitting.     

Relationship between factor XIII activity, fibrinogen, haemostasis screening tests and postoperative bleeding in cardiopulmonary bypass surgery

We investigated the relationship between factor XIII, fibrinogen, blood coagulation screening tests and postoperative bleeding in 98 patients undergoing cardiopulmonary bypass (CPB) surgery. All patients received aprotinin. Blood samples were collected preoperatively (T1),after termination of CPB (T2),12 h (T3) and 24 h (T4) after surgery to determine FXIII activity, fibrinogen, platelet count, prothrombin time (PT), activated partial thromboplastin time (APTT) and D-dimers (DD). Laboratory results were correlated with the chest tube drainage 24 h after surgery and compared between patients with 24-hour chest tube drain volumes in the lower (Group 1) with those in the upper tertile (Group 3). Median FXIII and fibrinogen levels dropped by 33.9% and 34.2%, respectively, during CPB. No association between FXIII activity and the extent of postoperative bleeding was found. However, chest tube bleeding was significantly correlated with preoperative and postoperative fibrinogen. This was confirmed by comparing Groups 1 and 3. Group 3 patients had significantly lower fibrinogen levels than Group 1 at T1 - T4, although most fibrinogen values were within or above the reference range (medians, g/l: 3.5 vs. 4.0, p = 0.043 at T1; 2.3 vs. 2.7, p = 0.015 at T2; 2.9 vs. 3.3, p = 0.008 at T3; 4.2 vs. 5.2, p = 0.002 at T4). There was also a significant relationship of platelet count, PT and APTT, as measured after CPB (T2), with postoperative chest tube drainage. In conclusion, plasma FXIII activity does not influence postoperative bleeding in patients undergoing CPB surgery. There is however an inverse association between preoperative or postoperative plasma fibrinogen levels and postoperative bleeding. These findings indicate a modulation of postoperative bleeding by fibrinogen levels.     

Physical and biological characterization of superparamagnetic iron oxide- and ultrasmall superparamagnetic iron oxide-labeled cells: a comparison

RATIONALE: Superparamagnetic iron-oxide particles are used frequently for cellular magnetic resonance imaging and in vivo cell tracking. The purpose of this study was to compare the labeling characteristics and efficiency as well as toxicity of superparamagnetic iron oxide (SPIO) and ultrasmall superparamagnetic iron oxide (USPIO) for 3 cell lines. METHODS: Using human fibroblasts, immortalized rat progenitor cells and HEP-G2-hepatoma cells, dose- and time-dependence of SPIO and USPIO uptake were evaluated. The amount of intracellular (U)SPIO was monitored over 2 weeks after incubation by T2-magnetic resonance relaxometry, ICP-mass-spectrometry, and histology. Transmission-electronmicroscopy was used to specify the intracellular localization of the endocytosed iron particles. Cell death-rate and proliferation-index were assessed as indicators of cell-toxicity. RESULT: For all cell lines, SPIO showed better uptake than USPIO, which was highest in HEP-G2 cells (110 +/- 2 pg Fe/cell). Cellular iron concentrations in progenitor cells and fibroblasts were 13 +/- 1pg Fe/cell and 7.2 +/- 0.3pg Fe/cell, respectively. For all cell lines T2-relaxation times in cell pellets were below detection threshold (<3 milliseconds) after 5 hours of incubation with SPIO (3.0 micromol Fe/mL growth medium) and continued to be near the detection for the next 6 days. For both particle types and all cell lines cellular iron oxide contents decreased after recultivation and surprisingly were found lower than in unlabeled control cells after 15 days. Viability and proliferation of (U)SPIO-labeled and unlabeled cells were not significantly different. CONCLUSIONS: The hematopoetic progenitor, mesenchymal fibroblast and epithelial HEP-G2 cell lines accumulated SPIO more efficiently than USPIO indicating SPIO to be better suited for cell labeling. However, the results indicate that there may be an induction of forced cellular iron elimination after incubation with (U)SPIO.     

Multimodale Bildgebung multipler Leberläsionen bei einem jungen Patienten

The classification of liver lesions is often problematic in particular if they are multiple and show an heterogeneous shape. Here we report of a young patient with multiple liver lesions of up to 3 cm size. Using ultrasound, the lesions were hyper-, hypoechogen or mixed. In serial contrast enhanced CT scans some of the lesions showed the typical enhancement pattern of hemangiomas, however, the diagnosis could still not be faithfully determined for all lesions. Therefore, the patient was conducted to contrast enhanced MRI (Gd-DTPA and MnDPDP). While with Gd-DTPA some of the lesions showed a strong enhancement, they remained hypointense after administration of MnDPDP. Finally to exclude a metastatic disease a (99m)Tc-erythrocyte SPECT was performed confirming the diagnosis of hemangiomas for most of the lesions. Diagnosis was not assessed by biopsy because this would only clarify the diagnosis for one or few of the lesions. The patient was subsequently followed up for 3 years and all lesions remained unchanged. This case clearly illustrates the difficulty to get a certain diagnosis of multiple liver lesions with heterogeneous appearance despite the multimodal diagnostic conduct.     

Time-resolved contrast-enhanced three-dimensional pulmonary MR-angiography: 1.0 M gadobutrol vs. 0.5 M gadopentetate dimeglumine

PURPOSE: To compare contrast characteristics and image quality of 1.0 M gadobutrol with 0.5 M Gd-DTPA for time-resolved three-dimensional pulmonary magnetic resonance angiography (MRA). MATERIALS AND METHODS: Thirty-one patients and five healthy volunteers were examined with a contrast-enhanced time-resolved pulmonary MRA protocol (fast low-angle shot [FLASH] three-dimensional, TR/TE = 2.2/1.0 msec, flip angle: 25 degrees, scan time per three-dimensional data set = 5.6 seconds). Patients were randomized to receive either 0.1 mmol/kg body weight (bw) or 0.2 mmol/kg bw gadobutrol, or 0.2 mmol/kg bw Gd-DTPA. Volunteers were examined three times, twice with 0.2 mmol/kg bw gadobutrol using two different flip angles and once with 0.2 mmol/kg bw Gd-DTPA. All contrast injections were performed at a rate of 5 mL/second. Image analysis included signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measurements in lung arteries and veins, as well as a subjective analysis of image quality. RESULTS: In patients, significantly higher SNR and CNR were observed with Gd-DTPA compared to both doses of gadobutrol (SNR: 35-42 vs.17-25; CNR 33-39 vs. 16-23; P < or = 0.05). No relevant differences were observed between 0.1 mmol/kg bw and 0.2 mmol/kg bw gadobutrol. In volunteers, gadobutrol and Gd-DTPA achieved similar SNR and CNR. A significantly higher SNR and CNR was observed for gadobutrol-enhanced MRA with an increased flip angle of 40 degrees. Image quality was rated equal for both contrast agents. CONCLUSION: No relevant advantages of 1.0 M gadobutrol over 0.5 M Gd-DTPA were observed for time-resolved pulmonary MRA in this study. Potential explanations are T2/T2*-effects caused by the high intravascular concentration when using high injection rates.     

Perfusion CT in patients with advanced bronchial carcinomas: a novel chance for characterization and treatment monitoring?

Advanced bronchial carcinomas by means of perfusion and peak enhancement using dynamic contrast-enhanced multislice CT are characterized. Twenty-four patients with advanced bronchial carcinoma were examined. During breathhold, after injection of a contrast-medium (CM), 25 scans were performed (1 scan/s) at a fixed table position. Density-time curves were evaluated from regions of interest of the whole tumor and high- and low-enhancing tumor areas. Perfusion and peak enhancement were calculated using the maximum-slope method of Miles and compared with size, localization (central or peripheral) and histology. Perfusion of large tumors (>50 cm³) averaged over both the whole tumor (P=0.001) and the highest enhancing area (P=0.003) was significantly lower than that of smaller ones. Independent of size, central carcinomas had a significantly (P=0.04) lower perfusion (mean 27.9 ml/min/100 g) than peripheral ones (mean 66.5 ml/min/100 g). In contrast, peak enhancement of central and peripheral carcinomas was not significantly different. Between non-small-cell lung cancers and small-cell lung cancers, no significant differences were observed in both parameters. In seven tumors, density increase after CM administration started earlier than in the aorta, indicating considerable blood supply from pulmonary vessels. Tumor perfusion was dependent on tumor size and localization, but not on histology. Furthermore, perfusion CT disclosed blood supply from both pulmonary and/or bronchial vessels in some tumors.Abbreviations AIF arterial input function - CT computed tomography - CM contrast media - ROI region of interest - SCLC small-cell lung cancer - NSCLC non-small-cell lung cancer - SD standard deviation