Prevention of activated brown adipose tissue on 18F-FDG-PET scans of young lymphoma patients: results of an ancillary study within the EuroNet-PHL-C2 trial.

Activated brown fat (aBAT) is known to affect the evaluation of 18F-FDG PET scans, especially in young patients. The aim of this study was to determine factors influencing the occurrence of aBAT, and to investigate the effectiveness of the two preventive measures, warming and beta-blocker (propranolol) administration. Five-hundred-twenty-eight 18F-FDG-PET scans of 241 EuroNet-PHL-C2 trial patients from 41 nuclear medicine departments in Germany and Czech Republic were screened for aBAT. The occurrence of aBAT was analyzed with patient characteristics (age, sex, body mass index, predisposition to aBAT), weather data at the day of 18F-FDG PET scanning as well as the preventive measures taken. Potentially important factors from univariate analyses were included into a logistic regression model. Warming as a preventive measure was used in 243 18F-FDG-PET scans, propranolol was administered in 36, warming and propranolol were combined in 84, and no preventive measures were taken in 165 scans. Whereas age, sex and body mass index had no clear impact, there was an individual predisposition to aBAT. Logistic regression model revealed that the frequency of aBAT mainly depends on the outside temperature (p = 0.005) and can be effectively reduced by warming (p = 0.004), the administration of unselective beta-blocker or the combination of both. Warming is a simple, cheap and non-invasive method to reduce the frequency of aBAT. However, the effect of warming decreases with increasing outside temperatures. Administration of propranolol seems to be equally effective and provides advantages whenever the positive effect of warming is compromised. The combination of both preventive measures could have an additive effect.

Factors influencing the success of aerial rabies vaccination of foxes.

Sylvatic rabies has been eradicated from most of Central Europe, but cases still occur in the Balkans. Oral rabies vaccination of foxes is an effective method for controlling the disease. The aim of this study was to evaluate the success of aerial vaccination campaigns conducted in Montenegro by identifying ecological, environmental and climatic factors that influenced the prevalence of antibodies to the rabies vaccine. To monitor the bait uptake and the serological responses to vaccination, foxes were shot by hunters. Of 175 shot foxes, 142 foxes (81.1%) had consumed baits. Of these only a total of 81 (57.0%) tested positive for rabies vaccine antibodies, possibly, due to the delayed uptake of bait in which the rabies vaccine was already inactivated. We found that low vaccination responses were associated with high fox density and bait delivery in open areas. In high fox density habitat, bait uptake might be delayed as other food and prey options for foxes are abundant. Similarly, delayed bait uptake probably occurred in open areas as such areas are less frequently used by foxes. The findings of this study suggest that efficacy of oral rabies vaccination by aerial delivery is associated with landscape features.

Automatic volume delineation in oncological PET. Evaluation of a dedicated software tool and comparison with manual delineation in clinical data sets.

AIM: Evaluation of a dedicated software tool for automatic delineation of 3D regions of interest in oncological PET. PATIENTS, METHODS: The applied procedure encompasses segmentation of user-specified subvolumes within the tomographic data set into separate 3D ROIs, automatic background determination, and local adaptive thresholding of the background corrected data. Background correction and adaptive thresholding are combined in an iterative algorithm. Nine experienced observers used this algorithm for automatic delineation of a total of 37 ROIs in 14 patients. Additionally, the observers delineated the same ROIs also manually (using a freely chosen threshold for each ROI) and the results of automatic and manual ROI delineation were compared. RESULTS: For the investigated 37 ROIs the manual delineation shows a strong interobserver variability of (26.8±6.3)% (range: 15% to 45%) while the corresponding value for automatic delineation is (1.1±1.0)% (range: <0.1% to 3.6%). The fractional deviation of the automatic volumes from the observer-averaged manual ones is (3.7±12.7)%. CONCLUSION: The evaluated software provides results in very good agreement with observer-averaged manual evaluations, facilitates and accelerates the volumetric evaluation, eliminates the problem of interobserver variability and appears to be a useful tool for volumetric evaluation of oncological PET in clinical routine.

Effects of cold sphere walls in PET phantom measurements on the volume reproducing threshold.

We studied quantitatively the effects of the discontinuity introduced in an otherwise homogeneous background by the cold walls of the standard spherical glass inserts commonly used in phantom measurements for calibration of threshold-based approaches to volumetric evaluation of PET investigations. We concentrated especially on the question of threshold-based volume determination. We computed analytically the convolution of an isotropic Gaussian point-spread function with the insert geometry (hot sphere + cold wall + warm background) and derived the theoretical background dependence of the volume reproducing threshold. This analysis shows a clear wall-related reduction of the optimal threshold with increasing background. The predictions of our theoretical analysis were verified in phantom measurements at background fractions between 0 and 0.29. Defining the background-corrected relative threshold [formula: see text] (T(abs): absolute volume reproducing threshold, A: measured activity at centre, B: background), we find that for a wall-less sphere T is independent of the background level. In the presence of cold walls, T drops (for not too small spheres, where recovery at the centre approaches 100%) from about 43% at B/A = 0 to about 25% at B/A = 0.5. Applying these thresholds to wall-less spheres leads to sizeable overestimates of the true volumes (43% at B/A = 0.5 for a sphere of 6 ml volume). We conclude that phantom measurements with standard sphere inserts for calibration of optimal thresholding algorithms introduce a systematic bias if performed at finite background levels. The observed background dependence is an artefact of the measurement procedure and does not reflect the conditions present in actual patient investigations.

Rabies in Europe--trends and developments.

Rabies continues to be a major public health concern both in Europe and worldwide. In the greater part of the European continent the disease has been eradicated, or its incidence drastically reduced, by oral vaccination of wildlife reservoirs. Yet, 'hot spots' still remain in north-eastern and south-eastern Europe with a high temporal variation of disease distribution in the previous decade. Rabies is predominantly transmitted by the red fox; but in recent years, especially in Eastern European countries, an independent infection cycle in raccoon dogs seems to have developed. Although countries such as the Czech Republic, Slovenia and Poland achieved very impressive rabies control results and trend analyses of rabies occurrence showed a long- and short-term decrease, there is still need for improved rabies surveillance and control in Europe. The Rabies Bulletin Europe (RBE), a quarterly, printed and on-line publication, aims to improve this situation. Besides the need to improve the quality of data in some countries, it will provide a public domain rabies database in the near future. Further strategic cooperation is necessary to control the disease in areas of European public health concern.

Fox rabies in Germany - an update.

In comparison with conventional methods of wildlife rabies control, oral rabies vaccination of foxes (ORV) is without doubt the most (cost-) effective method in wildlife rabies control. As a result of ORV, several European countries have become rabies-free. Although rabies had been eliminated from much of Germany, there still exists a residual rabies focus in the border triangle of Hesse, Baden-Wurttemberg and Rhineland Palatinate. Corrective actions have been initiated to eliminate this last remaining rabies hotspot in Germany.

Matched concurrent case-control study of risk factors for feather pecking in hens on free-range commercial farms in the UK.

1. The aim of the study was to compare the management and husbandry of free-range flocks in the UK where feather pecking was either present (case) or absent (control). 2. One hundred flocks were enrolled into a concurrent case-control study: 50 where birds had recently started feather pecking, and 50 matched control flocks where birds of the same age had not started feather pecking. 3. Information was obtained from a detailed interview with the flock manager, and by direct inspection of the flock, house and range. 4. Initial univariate analyses revealed that case flocks were more likely to comprise ISA Brown than Lohmann, were more likely to be restricted from litter areas to prevent floor eggs, and were less likely to use the outside range. 5. Cluster analysis indicated that feather pecking was not associated with any particular husbandry system. 6. The only influential risk factor significant in the multivariable conditional logistic regression analysis was use of the outdoor range. The risk of feather pecking was reduced 9-fold in flocks where more than 20% of birds used the range on sunny days (odds ratio = 0.12). Use of the range was positively associated with the presence of trees and/or hedges on the range.

The impact of parity and duration of biotin supplementation on white line disease lameness in dairy cattle.

A field study was conducted to examine effects of oral biotin supplementation for up to 18 mo on risks of lameness in dairy cows. The study included a total of 900 cattle from five dairy farms in Gloucestershire, southwest U.K., in a within-herd randomized control trial. The data from this trial were used in this paper to investigate the impact of parity and duration of supplementation with oral biotin at 20 mg/d on white line disease (WLD) lameness. Analysis of the data indicated that WLD increased with increasing parity independent of biotin supplementation from approximately two cases per 100 cow years in primiparous cows to 15.5 cases per 100 cow years in all multiparous cows, but up to 47.7 cases per 100 cow years for cows in parities > or = 5. Supplementation with biotin reduced WLD lameness by 45% in multiparous cows down to 8.5 cases per 100 cow years, whereas the effect of biotin supplementation in primiparous cows was not significant. Although numerical reductions in WLD lameness were observed for shorter periods of supplementation, a supplementation length of at least 6 mo was required to significantly reduce the risk of WLD lameness in multiparous cows. The effect of biotin supplementation in reducing lameness has potential impact for both animal welfare and farm economics.

Familial and metachronous malignant lymphoma: absence of constitutional p53 mutations.

Familial and metachronous aggregations of malignant lymphoma are well-documented, but the molecular basis of a predisposition for development of lymphoma is as yet unclear. Malignant lymphomas have been described as part of the spectrum of neoplasias in Li-Fraumeni syndrome (LFS), which is associated with constitutional mutations of p53. However, p53 germline mutations have also, albeit less frequently, been described in patients not fitting the clinical definition of LFS. To clarify whether a genetic predisposition for lymphoma is associated with constitutional p53 mutations, DNA from normal blood lymphocytes of 12 lymphoma patients with a family history of lymphoma and/or with metachronous lymphoma (median age 37 years) was examined for mutations of p53 exons 4-8. One patient had four first-degree relatives with Hodgkin's disease, acute leukemia, and carcinomas, but the family history did not fulfill criteria of LFS. Four patients with Hodgkin's disease were diagnosed with metachronous non-Hodgkin's lymphoma as a second malignant neoplasm. No constitutional p53 mutations were detected in any of these patients, implying that outside the clinical spectrum of LFS, constitutional p53 mutations are rare in patients with lymphomas.

Acute myelomonocytic leukemia secondary to synchronous carcinomas of the breast and lung, and to metachronous renal cell carcinoma.

We describe a patient in whom synchronous breast cancer and small-cell lung cancer, and metachronous renal cell carcinoma were diagnosed within an 11 months period. All three tumors were treated surgically, followed by administration of tamoxifen, adjuvant chemotherapy with etoposide (2.8 g/m2 total) and vindesine, and administration of interferon alpha and flutamide. The patient developed acute myelomonocytic leukemia 26 months after discontinuation of etoposide-containing chemotherapy. This pattern of multiple neoplasms fits the wider disease spectrum associated with germline mutations of the p53 gene; however, analysis of p53 exons 5-8 did not disclose any sequence abnormalities in this patient. In conclusion, clustering of four (synchronous and metachronous) malignancies may on rare occasions occur in an individual patient and in the absence of a family history of cancer; the sequence during which treatment of primary malignancies may result in treatment-related acute myelocytic leukemia is discussed.

Four year follow-up of the MemoryLens.

PURPOSE: To determine whether the long-term results of implantation of thermoelastic MemoryLens intraocular lenses (IOLs) are comparable to those of conventional poly(methyl methacrylate) (PMMA) IOLs. SETTING: St. Elisabeth Hospital, Dillingen, Germany. METHODS: This retrospective study compared visual acuity, astigmatism, lens decentration, biocompatibility, and posterior capsule opacification in 36 eyes with a MemoryLens with those in 36 eyes with a conventional PMMA IOL over 4 years. The MemoryLenses were implanted in 1991 after cataract extraction by phacoemulsification. RESULTS: Four years postoperatively, best corrected visual acuity was 20/20 to 20/25 in 63.9% of the MemoryLens group and 55.6% of the PMMA group. Mean astigmatism was 0.84 diopters (D) in the MemoryLens group and 1.20 D in the PMMA group. No cellular precipitates, as evaluated by biomicroscopy, or lens decentration greater than 0.5 mm were found in either group. Posterior capsule opacification, which developed in 22.2% in the MemoryLens group and 38.9% in the PMMA group, was treated with a neodymium: YAG laser capsulotomy. CONCLUSION: The MemoryLens allows small incision cataract surgery and long-term results that compare favorably with those of PMMA IOLs.