The effect of an environmental enrichment device on individually caged rabbits in a safety assessment facility

The primary enclosure of a laboratory animal's environment should encourage species-typical behavior and enhancement of the animal's well-being, as indicated by the Guide. Enrichment devices have been documented to decrease the incidence of stereotypical behaviors and increase overall activity of rabbits. An 8-week study was performed to evaluate the effect of an environmental enrichment device, stainless-steel rabbit rattles on spring clips, on individually housed rabbits in a Safety Assessment facility. We used 48 New Zealand White rabbits; the devices were placed on cages of 32 study rabbits, and 16 control rabbits had no devices. Food consumption measurements and observations of device manipulations (taken during a predetermined peak interaction 1-h timeframe) were collected 5 days per week. All rabbits were bled for evaluation of hematologic parameters for the stress triad (neutrophilia, lymphopenia, and eosinopenia) and weighed weekly. No significant differences were found between study and control rabbits when body weights, food consumption, and hematologic parameters were analyzed. Our study supports previous findings that interaction with enrichment devices decreases over time, thus indicating the need for frequent rotation of different enrichment devices. In addition, no adverse effects of the analyzed parameters were found, indicating that stainless-steel rabbit rattles on spring clips are suitable devices for safety assessment studies, in which the introduction of new variables is often unacceptable.

Imaging of chronic recurrent multifocal osteomyelitis of childhood first presenting with isolated primary spinal involvement

OBJECTIVE

Initial presentation with primary spinal involvement in chronic recurrent multifocal osteomyelitis of childhood (CRMO) is rare. Our objective was to review the imaging appearances of three patients who had CRMO who initially presented with isolated primary spinal involvement.

DESIGN AND PATIENTS

The imaging, clinical, laboratory and histology findings of the three patients were retrospectively reviewed. Imaging included seven spinal MR imaging scans, one computed tomography scan, nine bone scans, two tomograms and 16 radiographs. These were reviewed by two musculoskeletal radiologists and a consensus view is reported. All three patients presented with atraumatic spinal pain and had extensive bone spinal pathology. The patients were aged 11, 13 and 12 years. There were two females and one male.

RESULTS AND CONCLUSIONS

The initial patient had thoracic T6 and T8 vertebra plana. Bone scan showed additional vertebral body involvement. Follow-up was available over a 3 year period. The second patient had partial collapse of T9 and, 2 years later, of C6. Subsequently extensive multifocal disease ensued and follow-up was available over 8 years. The third patient initially had L3 inferior partial collapse and 1 year later T8 involvement with multifocal disease. Follow-up was available over 3 years. The imaging findings of the three patients include partial and complete vertebra plana with a subchondral line adjacent to endplates associated with bone marrow MR signal alterations. Awareness of the imaging appearances may help the radiologist to include this entity in the differential diagnosis in children who present with spinal pathology and no history of trauma. Histopathological examination excludes tumor and infection but with typical imaging findings may not always be necessary.

Follow-up in neuroblastoma: comparison of metaiodobenzylguanidine and a chimeric anti-GD2 antibody for detection of tumor relapse and therapy response

Early and correct diagnosis of local tumor recurrence, occurrence of metastases, and therapy response are essential in patients with neuroblastoma stage IV. The aim of the study was to evaluate the diagnostic value of metaiodobenzylguanidine (mIBG) and a chimeric GD2 antibody in the follow-up of patients with neuroblastoma. In a prospective study, mIBG (N = 31 scans) and immunoscintigraphy were compared with a chimeric antiganglioside antibody, ch14.18 (MAb) (N = 31 scans), labeled with technetium Tc 99m in the follow-up of 18 patients with stage IV neuroblastoma. The findings were compared with histologic findings, other imaging examinations, and clinical changes over the course of 4 to 6 years. For the diagnosis of local tumor recurrences, sensitivity was 80% for MAb and 70% for mIBG. Specificity was 93% for MAb and 72% for mIBG. The MAb was superior for the detection of skeletal metastases, with a sensitivity of 82% compared with 72% for mIBG. Specificity was 100% for both techniques. Also, for soft tissue/lymph node metastases, sensitivity for MAb was higher (50%) than for mIBG (31%). Specificity was 100% for each technique. In sequential studies, metastases were detected earlier with MAb (mean: 2.3 m for skeletal metastases, 3.6 m for soft tissue metastases) than with mIBG. After therapy, tumor uptake was visualized longer with mIBG (mean 6.3 m) than with MAb. The chimeric antibody ch14.18 is likely to be valuable for follow-up examinations and for assessment of therapy response because of earlier detection of new metastases.

Multiple rostral medullary nuclei can influence breathing in awake goats

The purpose of this study was to determine the effect on breathing of neuronal dysfunction in the retrotrapezoid (RTN), facial (FN), gigantocellularis reticularis (RGN), or vestibular (VN) nuclei of adult awake goats. Microtubules were chronically implanted to induce neuronal dysfunction by microinjection of an excitatory amino acid (EAA) receptor antagonist or a neurotoxin. The EAA receptor antagonist had minimal effect on eupneic breathing, but 8--10 days after injection of the neurotoxin, 7 of 10 goats hypoventilated (arterial PCO(2) increased 3.2 +/- 0.7 Torr). Overall there were no significant (P > 0.10) effects of the EAA receptor antagonist on CO(2) sensitivity. However, for all nuclei, > or =66% of the antagonist injections altered CO(2) sensitivity by more than the normal 12.7 +/- 1.6% day-to-day variation. These changes were not uniform, inasmuch as the antagonist increased (RTN, n = 2; FN, n = 7; RGN, n = 6; VN, n = 1) or decreased (RTN, n = 2; RGN, n = 3; VN, n = 2) CO(2) sensitivity. Ten days after injection of the neurotoxin into the FN (n = 3) or RGN (n = 5), CO(2) sensitivity was also reduced. Neuronal dysfunction also did not have a uniform effect on the exercise arterial PCO(2) response, and there was no correlation between effects on CO(2) sensitivity and the exercise hyperpnea. We conclude that there is a heterogeneous population of neurons in these rostral medullary nuclei (or adjacent tissue) that can affect breathing in the awake state, possibly through chemoreception or chemoreceptor-related mechanisms.

beta-Endorphin immunoreactive material and authentic beta-endorphin in the plasma of males undergoing anaerobic exercise on a rowing ergometer

Adrenocorticotropic hormone (ACTH), beta-endorphin immunoreactive material (beta-endorphin IRM), and authentic beta-endorphin (1 -31) have been determined in the plasma of 23 volunteers undergoing anaerobic exercise on a rowing ergometer. The volunteers had different histories of training from occasional physical activities up to intensive preparation for international rowing competitions. ACTH and beta-endorphin-IRM were determined using commercially available immunometric assays; for determination of beta-endorphin (1-31) a highly specific two-site fluid phase immunoprecipitation radioimmunoassay was developed, which did not cross-react with any beta-endorphin derivative or any other opioid peptide tested. In agreement with reports from the literature ACTH and beta-endorphin-IRM concentrations in the plasma rose upon anaerobic exercise in all 23 subjects; this increase in the ACTH and beta-endorphin IRM levels was significantly correlated with the increase of lactate levels observed upon anaerobic exercise. Authentic beta-endorphin (1-31) was only found in two plasma samples containing minor concentrations of the peptide. We conclude that the beta-endorphin immunoreactive material released into blood under anaerobic exercise is identical with authentic beta-endorphin (1-31) only to a minor extent and thus should not be called "beta-endorphin". The major part of the material in fact released into the blood upon anaerobic exercise is probably identical with beta-lipotropin and further components so far unknown.

Renal pathology after arterial yttrium-90 microsphere administration in pigs. A model for superselective radioembolization therapy

RATIONALE AND OBJECTIVES

To test the selectivity of tissue damage in radioembolization, the authors performed an experimental study using superselective administration of yttrium-90 particles to deliver up to 100 Gy to the porcine kidney. Patterns and severity of damage in test organs were compared with controls, and the feasibility of this model is discussed.

METHODS

Eight sows were included in the study. Bio-Rex 70 particles were applied via selective catheterization of the renal artery. Four pigs received inactive particles and four pigs received active particles. Organ distribution and shunting of yttrium-90 were determined, and kidney damage patterns were histologically analyzed.

RESULTS AND CONCLUSIONS

The model demonstrates that yttrium-90-labeled resin particles can superselectively be applied. Retention of beta activity in the target organ was more than 95%. In addition to tissue shrinkage from mechanical obstruction, considerable damage ensued mainly by radiation-induced arterial necrosis and arteritis.

Positron emission tomography and ultrasonography. A comparative retrospective study assessing the diagnostic validity in lymph node metastases of malignant melanoma

BACKGROUND AND DESIGN

A retrospective study involving 20 patients with melanoma with clinically suspicious lymph nodes was conducted to compare the diagnostic validity of fludeoxyglucose F 18 positron emission tomography (PET) and real-time ultrasonography in lymph node metastases of malignant melanoma.

RESULTS

A total of 83 lymph nodes were assessed with ultrasonography and PET. Imaging results were confirmed by histologic studies or close follow-up ultrasonographic examinations. Positron emission tomography revealed a sensitivity of 74% and a specificity of 93%. Both investigative methods show comparative sensitivity and specificity.

CONCLUSIONS

Ultrasonography is much easier to perform, less time-consuming, and less expensive than PET and it is nonhazardous; therefore, it is ideal for follow-up procedures. Since in routine staging procedures, only sites of expected lymph node involvement are examined, there is a risk of metastases being missed in cases of atypical drainage patterns. Fludeoxyglucose F 18 PET can image proliferating tumors in multiple organ systems and lymph node sites in one session, making it suitable for screening in primary staging procedures and for monitoring response to therapy. Since it is based on metabolic changes, there is good differentiation between scar and tumor tissue. Major disadvantages are restricted access to investigation centers, high imaging costs, and limited anatomical location of metastatic lesions. We conclude that PET does not offer significant advantages in the diagnosis of lymph node metastases compared with ultrasonography.

Somatostatin receptor scintigraphy in central nervous system tumors: role of blood-brain barrier permeability

Somatostatin receptors are expressed in meningiomas and low-grade gliomas, raising the hope that scintigraphy with 111In-DTPA-D-Phe1-octreotide might be helpful in the in vivo localization, differential diagnosis and postoperative/postradiotherapy brain tumor follow-up.

METHODS

Indium-111-DTPA-D-Phe1-octreotide scintigraphy and brain scintigraphy using 99mTc-DTPA as a nonspecific tracer for blood-brain barrier integrity were simultaneously performed in 60 patients with CNS tumors using dual-isotope acquisition mode SPECT. For 23 patients, the scintigraphic findings were also compared with in vitro somatostatin receptor autoradiography of surgical biopsy specimens.

RESULTS

In meningiomas (located outside the blood-brain barrier), the somatostatin receptor scan showed all tumors and scintigraphic signal intensity correlating with in vitro SSR density positive in all meningiomas. Less contrast was seen on 99mTc-DTPA scans. In all tumors inside the blood-brain barrier, the 111In-DTPA-D-Phe1-octreotide scan visualized the tumors with a disrupted blood-brain barrier, as seen by 99mTc-DTPA scintigraphy. Discrepancies, however, were observed between somatostatin receptor scintigraphy and in vitro receptor autoradiography.

CONCLUSION

Combined somatostatin receptor and 99mTc-DTPA scintigraphy may be helpful for noninvasive differentiation between meningiomas and other CNS tumors. False-negative scans were observed as a result of shielding by the intact blood-brain barrier. Interpretation of negative and positive somatostatin receptor scans in CNS tumors must therefore be done with caution.

[Methods for the superselective radioembolization of liver tumors with 90yttrium-resin particles]

An improved technique for radioembolization of non-resectable liver tumours is described. 90yttrium-labelled Bio-Rex-70 particles which show high stability and good tissue tolerance are applied superselectively via the tumour-feeding artery using a microcatheter. The procedure includes both diagnostic and therapeutic angiography. Angiography is complemented by angioscintigraphy (99mTc-MAP) and an i.v. 99mTc-colloid scan of the liver. Thus it is possible pretherapeutically to evaluate tumour volume and dose distribution both in and outside of the liver, and in the lung due to shunt. These estimates were re-evaluated posttherapeutically. Radioembolization can thus be quantified and the doses absorbed by the tumour as well as the liver and lung can be calculated.

Superselective radioembolization of hepatocellular carcinoma: 5-year results of a prospective study

Twenty patients with unresectable hepatocellular carcinoma (HCC) were followed up to 5 years after transarterial radiotherapy with 90Y-resin particles. Diagnostic radioembolizations of 99mTc-macroaggregates facilitated scintigraphic assessment of activity distribution, dose evaluation and final procedural verification. The overall survival rates were 56, 38 and 14% (after 1, 2 and 3 years, resp.). Patients with unifocal HCC and a single feeding artery (n = 7) even presented 83, 67 and 40% (2 alive after 2.75 and 4 years). With multiple arteries (n = 7), the longest survival was 26 months. Patients with multifocal HCC survived up to 33 months after selective radioembolization. Quality of life was improved in all. Survival was positively correlated with absorbed dose but residual/recurrent tumour occurred even after > or = 300 Gy. Post-treatment symptoms were minimal (35 applications), pulmonary shunt rates were correctly predicted and pulmonary complications avoided.

90Y-resin particles--animal experiments on pigs with regard to the introduction of superselective embolization therapy

Resin particles (diameter 45-75 microns) were labelled with 90Y, suspended in a glucose/dextran solution and infused into the kidneys of 3-month-old pigs (tumour model). Both kidneys of each animal were embolized with particles, but only one with active (90Y loaded) particles and the other, for comparison, with inactive particles. The organ measurements showed less than 1% of injected activity in bone, bone marrow, liver and lung compared to greater than 99% retention by the kidneys. Only minimal shunted activity was found in blood (less than 0.27%) and urine (less than 0.07%). There was a clear shrinkage of the 90Y-treated kidneys with a reduction in weight of up to 50%. Histologically, the ischaemic lesions (infarcts and atrophy) were clearly more pronounced and extensive in the 90Y-embolized kidneys than in the non-radioactive embolized kidneys. Furthermore, severe arterial wall changes and fibrotic necrosis due to radiation damage were observed in the 90Y-treated kidneys. It is concluded that with intra-arterially applied particles a dose of about 100 Gy is sufficient to completely destroy tissue-specific structures. Complications due to acute necrosis or inflammatory reactions were not observed, and there were no shunt related alterations seen in the liver or lungs. The 90Y-loaded resin particles are considered suitable for a super selective intra-arterial radioembolization.

[Fluoridation measures and caries prevalence in school children in the former DDR]

Statistical analysis of 3,576 DMFT counts from three million observations of children aged 6 to 16 in East Germany shows a strong time-lagged relationship with fluoridation activities. More significant results, however, are found due to age and a score of socioeconomic factors. Additionally, caries prevalence decreases with time. Conversely, DMFT is not affected by size or type of dental staff, neither absolutely nor relatively.

[Present level of software production for the use of microcomputers, PCh's and terminals in the stomatology of the GDR]

The informatics team of the Stomatological Society of the GDR provides a complete list of presently available program packages for home, 8 and 16-bit computers and a list of the programming teams. Main developments for the use of PC's in stomatology are described as well. By establishing clear lines for the development of software, standardized user software can be guaranteed.

[Radioimmunoscintigraphy with a 99mTc-labeled F(ab')2 fragment of a monoclonal antibody (HMW-MAA 225.28S) in 71 patients with malignant melanoma]

In 71 patients with malignant melanoma 85 radioimmunoscintigraphies (RIS) with 99mTc-radiolabeled F(ab')2 fragments of a murine monoclonal antibody have been performed. The antibody is specific for an epitope of the HMW-MAA glycoprotein complex which is present in 90% of melanoma tissue samples. Sensitivity for RIS was 79% (73 metastatic sites out of a total of 92). 20 previously unknown lesions were found and there were also 2 false positives. Conventional staging procedures alone revealed 78% of the metastatic sites (72 of 92). No side effects were observed. RIS was especially useful for detection of lymph node metastases not found by conventional methods and is therefore considered complementary to conventional preoperative staging procedures.

Surfactants: a survey of short-term genotoxicity testing

The available results for tests on over 200 surfactants in nine short-term genotoxicity assay systems were reviewed. These tests included the Salmonella/microsome mutation assay, bacterial DNA repair tests, mitotic recombination in Saccharomyces cerevisiae, the mouse lymphoma cell-mutation assay, unscheduled DNA synthesis and sister chromatid exchange assays in mammalian cells, mammalian chromosome damage tests in vitro and in vivo, the dominant lethal test in rodents, and mammalian cell-transformation tests. The collected data cover all four major classes of surfactants: anionic, cationic, nonionic and amphoteric. The results of these genotoxicity tests were overwhelmingly negative. Although there were occasional positive results in bacterial or cell-transformation systems, the testing performed to date indicates that surfactants have negligible potential to cause genetic damage. The available data also indicate that none of the assays were incompatible with testing surfactants for genotoxicity.

[Repetitive work and psychosomatic complaints]

200 workers of the Swiss watch industry were examined in an interdisciplinary study on the effect of repetitive work on the wellbeing of the worker. Women doing repetitive work with little autonomy complained more often about psychosomatic problems than the male workers doing non-repetitive work. This difference is interpreted as a difference of sexe rather than one of the work situation. However, there is a significant difference in the complaint about nervosity between women being paid monthly and women who were paid by piece or by hour with a premium.