Role of psa levels and pathological stadiation before radiation therapy in predicting mp-MRI results in patients with prostate cancer recurrence after radical prostatectomy.

OBJECTIVE: To evaluate PSA value in mp-MRI results prediction, analyzing patients with high (GS≥8, pT≥3, pN1) and low grade (GS<8, pT<3, pN0) Prostate Cancer (PCa). MATERIALS AND METHODS: One hundred eighty-eight patients underwent 1.5-Tmp-MRI after Radical Prostatectomy (RP) and before Radiotherapy (RT). They were divided into 2 groups: A and B, for patients with biochemical recurrence (BCR) and without BCR but with high local recurrence risk. Considering Gleason Score (GS), pT and pN as independent grouping variables, ROC analyses of PSA levels at primary PCa diagnosis and PSA before RT were performed in order to identify the optimal cut-off to predict mp-MRI result. RESULTS: Group A and B showed higher AUC for PSA before RT than PSA at PCa diagnosis, in low and high grade tumors. For low grade tumors the best AUC was 0.646 and 0.685 in group A and B; for high grade the best AUC was 0.705 and 1 in group A and B, respectively. For low grade tumors the best PSA cut-off was 0.565-0.58ng/mL in group A (sensitivity, specificity: 70.5%, 66%), and 0.11-0.13ng/mL in B (sensitivity, specificity: 62.5%, 84.6%). For high grade tumors, the best PSA cut-off obtained was 0.265-0.305ng/mL in group A (sensitivity, specificity: 95%, 42.1%), and 0.13-0.15ng/mL in B (sensitivity, specificity: 100%). CONCLUSION: Mp-MRI should be performed as added diagnostic tool always when a BCR is detected, especially in high grade PCa. In patients without BCR, mp-MRI results, although poorly related to pathological stadiation, still have a good diagnostic performance, mostly when PSA>0.1-0.15ng/mL.

Impact of adipose tissue distribution on prostate cancer recurrence after radical prostatectomy.

OBJECTIVE: The aim of our study is to correlate the CT adipose tissue distribution and recurrence risk of Prostatic Cancer (PCa) after Radical Prostatectomy (RP). Furthermore, we evaluated the association of adipose tissue and PCa aggressiveness. MATERIALS AND METHODS: We identified two groups of patients based on presence (group A) and absence (group B or control group) of Bio-chemical Recurrence (BCR) after RP. A semi-automatic function able to recognize the typical attenuation values of adipose tissue was used for sub-cutaneous (SCAT), visceral (VAT), total (TAT) and periprostatic (PPAT) adipose tissues. For both groups of patients, a descriptive analysis of continuous variables and categorical variables was performed. RESULTS: After comparing between groups, a statistically significant difference was found for VAT (p<0.001) and for VAT/TAT ratio (p=0.013). No statistically significant correlation was found for PPAT and SCAT, even if higher values were found in patients with high grade tumors. CONCLUSION: This study confirms visceral adipose tissue as a quantitative imaging parameter related to oncological risk of PCa recurrence development, and the role of abdominal fat distribution measured with CT before RP as an important tool to predict the PCa recurrence risk, particularly in patients with high grade tumors.

The role of multiparametric mri in the diagnosis of local recurrence after radical prostatectomy and before salvage radiotherapy.

PURPOSE: Assess multiparametric-MRI (mp-MRI) diagnostic accuracy in the detection of local recurrence of Prostate Cancer (PCa) after Radical Prostatectomy (PR) and before Radiation Therapy (RT). MATERIALS AND METHODS: A total of 188 patients underwent 1.5-T mp-MRI after RP before RT. Patients were divided into two groups: with biochemical recurrence (group A) and without but with high risk of local recurrence (group B). Continuous variables were compared between two groups using T-Student; categoric variables were analyzed using Pearson chi-square. ROC analysis was performed considering PSA before RT, ISUP, pT and pN as grouping variables. RESULTS: PCa recurrence (reduction of PSA levels after RT) was 89.8% in the group A and 80.3% in the group B. Comparing patients with and without PCa recurrence, there was a significant difference in PSA values before RT for group A and for PSA values before RT and after RT for group B. In group A, there was a significant correlation between PSA before RT and diameter of recurrence and between PSA before RT and time spent before recurrence. The mp-MRI diagnostic accuracy in detecting PCa local recurrence after RP is of 62.2% in group A and 38% in group B. DWI is the most specific MRI-sequence and DCE the most sensitive. For PSA = 0.5 ng/ml, the AUC decreases while sensitivity and accuracy increase for each MRI-sequence. For PSA = 0.9 ng/ml, DCE-AUC increases significantly. CONCLUSION: mp-MRI should always be performed before RT when a recurrence is suspected. New scenarios can be opened considering the role of DWI for PSA ≤ 0.5 ng/ml.

Body composition and metabolic changes during a 520-day mission simulation to Mars.

PURPOSE: The "Mars-500 project" allowed to evaluate the changes in psychological/physiological adaptation over a prolonged confinement, in order to gather information for future missions. Here, we evaluated the impact of confinement and isolation on body composition, glucose metabolism/insulin resistance and adipokine levels. METHODS: The "Mars-500 project" consisted of 520 consecutive days of confinement from June 3, 2010 to Nov 4, 2011. The crew was composed of six male subjects (three Russians, two Europeans, and one Chinese) with a median age of 31 years (range 27-38 years). RESULTS: During the 520-day confinement, total body mass and BMI progressively decreased, reaching a significant difference at the end (417 days) of the observation period (- 9.2 and - 5.5%, respectively). Fat mass remained unchanged. A progressive and significant increase of fasting plasma glucose was observed between 249 and 417 days (+ 10/+ 17% vs baseline), with a further increase at the end of confinement (up to + 30%). Median plasma insulin showed a non-significant early increment (60 days; + 86%). Total adiponectin halved (- 47%) 60 days after hatch closure, remaining at this nadir (- 51%) level for a further 60 days. High molecular weight adiponectin remained significantly lower from 60 to 168 days. CONCLUSIONS: Based on these data, countermeasures may be envisioned to balance the potentially harmful effects of prolonged confinement, including a better exercise program, with accurate monitoring of (1) the individual activity and (2) the relationship between body composition and metabolic derangement.

Diagnostic accuracy of 1.5 Tesla breast magnetic resonance imaging in the pre-operative assessment of axillary lymph nodes.

The purpose of this study was to test the accuracy of 1.5 Tesla magnetic resonance imaging (1.5T MRI) in the preoperative evaluation of axillary lymph nodes in patients with invasive breast cancer. The authors retrospectively analyzed 26 patients with invasive breast cancer who had undergone sentinel lymph node biopsy (SLNB) and/or axillary lymph node dissection (ALND). All patients had been submitted to preoperative contrast enhanced breast 1.5T MRI. On the basis of lymph nodes morphological and dynamic characteristics, lymph nodes were classified as "negative" (short axis < 5 mm), "borderline" (short axis > 5 mm, absence of a hilum) or "positive" (short axis > 5 mm, absence of a hilum and also other suspicious features). The authors compared 1.5T MRI results with the outcome of histological analysis performed according to the TNM criteria; sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) of 1.5T MRI were evaluated. Considering only the lymph nodes "positive", 1.5 T MRI showed: SE 37.8%, SP 99.3%, FP 0.7%, PPV 92.5%, and NPV 88.1%. However, considering also "borderline", 1.5T MRI achieved: SE 75.7%, SP 99.3%, FP 0.7%, PPV 96.1%, and NPV was 95%. Contrast enhanced breast 1.5T MRI is not yet a valid alternative to histological analysis but it is a valid tool for a preoperative study of the topography of axillary lymph nodes and has the potential to become a routine method for evaluating the metastatic lymph nodes before submission to ALND.

Apparent diffusion coefficient on 3.0 Tesla magnetic resonance imaging and prognostic factors in breast cancer.

AIM: The aim of the study was to evaluate whether the apparent diffusion coefficient (ADC) provided by 3.0 Tesla diffusion-weighted imaging (3T DWI) varies with the prognostic factors Ki67 and grading in invasive breast cancer. MATERIALS AND METHODS: Seventy-three patients with 75 invasive breast cancer lesions who had undergone 3.0 Tesla magnetic resonance imaging (MRI) for local staging were enrolled. All lesions were confirmed by histologic and immunohistochemical analysis. MRI included both dynamic contrast-enhanced and DWI sequences. ADC value was obtained for each lesion. Histologic tumor grade was established according to the Nottingham Grading System (NGS), while Ki67 expression was evaluated by MM1 clone IgG1 mouse anti-human monoclonal antibody. Patients were divided into the following groups: grade 1 (G1), grade 2 (G2), grade 1 plus grade 2 (G1+G2) and grade 3 (G3), and low Ki67 (< or = 14%), intermediate Ki67 (15%-30%), and high Ki67 (> or = 30%). ADC values were compared with the G and Ki67 groups. Statistical comparison was carried out using the Mann-Whitney U and the Kruskal-Wallis H test. RESULTS: ADC values were significantly higher in G3 than in G1+G2 tumors; no significant difference was observed when G1, G2, and G3 were compared. There was no statistically significant correlation between ADC values and Ki67 percentage (p > 0.05). DISCUSSION: ADC values obtained on 3T DWI correlate with low (G1+G2) and high-grade (G3) invasive breast carcinomas. CONCLUSION: ADC may be a helpful tool for identifying high-grade invasive breast carcinoma.

Endovascular radiofrequency renal denervation in treating refractory arterial hypertension: a preliminary experience.

PURPOSE: This study was done to investigate the efficacy and safety of percutaneous renal denervation with the Symplicity catheter for reducing blood pressure in patients with essential hypertension resistant to medical therapy (systolic blood pressure >160 mmHg despite the use of three or more antihypertensive drugs, including a diuretic). MATERIALS AND METHODS: In September 2010, five patients affected by essential hypertension resistant to medical therapy were treated. All patients were studied by computed tomography angiography (CTA) of the renal arteries before the procedure and underwent follow-up at 30 and 60 days with colour Doppler ultrasound (CDUS) with evaluation of resistive index, glomerular filtration rate (GFR), 24-h blood pressure and serum catecholamine concentration. Student's t test was used to assess the effectiveness of the procedure in lowering blood pressure. RESULTS: In treated patients, mean blood pressure at baseline was 171/100 mmHg [standard deviation (SD) ± 8/10]; mean GFR was 91.6 ml/min/1.73 m(2) (SD ± 15). Blood pressure after the procedure was reduced by -18/-5 and -13/-10 mmHg at 30 and 60 days, respectively, with a mean medication reduction of 3.6. No complications occurred during the intra- or periprocedural period or during short-term follow-up. CONCLUSIONS: The Symplicity system proved to be efficacious and without serious adverse events in reducing blood pressure and antihypertensive medication use in patients affected by essential hypertension resistant to medical therapy. Although encouraging, our data are preliminary and need to be validated by larger prospective randomised studies.

Organochlorine and heavy-metal contaminants in wild mammals and birds of Urbino-Pesaro Province, Italy: an analytic overview for potential bioindicators.

Tissue samples from 56 bird and 11 mammal species of different trophic levels, collected from 1994 to 1995 from the Urbino-Pesaro area in the Marche region of central Italy, were analyzed for the presence of organochlorine compounds (polychlorinated biphenyls and p,p'-DDE) and heavy metals (Pb, Cd, Cr, and Hg). Results revealed interspecies differences in pollutant residue concentrations. A clear relationship between contaminant and trophic levels emerged depending on several factors specific to the chemicals and the organisms, the importance of dietary accumulation, and metabolic capacity as it increased toward higher trophic levels. Polychlorinated biphenyls and p,p'-DDE were found in all of the bird and mammal species analyzed (bird- or fish-eating birds), and insectivore mammals showed the highest level of these contaminants. Pb and Hg residues were also widely detected and reflected trophic-level differences. The highest concentration of Pb was found in herbivorous or bird-eating aquatic invertebrates and in insectivorous mammals, particularly in the hedgehog (Erinaceus europaeus), whereas the highest Hg levels were found in fish-eating birds. All of the other heavy metals were detected at low concentrations and represented background levels for birds and mammals, with the exception of increased amounts of Cd and Cr, respectively, found in stone marten (Martes foina) and fox (Vulpes vulpes). Data from this study provided information on baseline levels of interest to monitor status and trends in chemical residue in biota in this specific area, and therefore they represent a tool to evaluate potential ecologic, wildlife, and human health exposure.

The endocrine disruptor atrazine accounts for a dimorphic somatostatinergic neuronal expression pattern in mice.

It has now been established that a large number of man-made and natural chemicals are capable of interfering with the action of natural hormones. In this category "endocrine disruptors" such as the herbicide atrazine, when administered at ecological low doses (1 or 100 microg/kg per day) from gestational day 14 to postnatal day 21, provided a clear dimorphic neurodegenerative pattern in some brain areas of the domestic mouse (Mus musculus). Indeed, the high concentration (100 microg/kg per day) with respect to the low concentration (1 microg/kg per day) induced relevant neuronal damage in extrahypothalamic sites, such as the cortical and striatal areas in both sexes. Marked alterations in other areas, including the hippocampal and hypothalamic nuclei, were mostly typical of the female. At the neuronal level, the neuropeptide somatostatin, specific for the secretion of growth hormone, seemed to be a major target of atrazine effects, as demonstrated by evident subtype2,3,5 receptor mRNA differences of this neuropeptide, at least for the first two subtypes. In particular, a very strong (p < 0.001) upregulation of subtype2 expressing neurons was detected in female hypothalamic areas, specifically the suprachiasmatic nucleus, whereas a similar downregulatory trend was reported for some extrahypothalamic areas such as the striatum. Interestingly, very strong upregulatory and downregulatory actions were detected for neurons expressing subtype3 in male hypothalamic and amygdalar regions and in the cortical and hippocampal areas, respectively. Overall, it appears that these first neurotoxicological effects of atrazine are very likely linked to dimorphic expression patterns of specific somatostatin subtypes in discrete but key hypothalamic and extrahypothalamic areas of Mus musculus.

Response of CD-1 mice to the chemical defence of a common arthropod (Ommatoiulus sabulosus).

In order to set up a novel and ethologically relevant methodology that could be applied to the study of olfactory capabilities in transgenic mice, we analysed the behavioural responses of sexually mature male and female CD-1 mice individually exposed to a striped millipede, Ommatoiulus sabulosus (L.), a very common myriapod species that secretes a repulsive and persistent odour in the presence of a predator. As control, we exposed mice to a larva of the lepidopteran Greater wax moth, Galleria mellonella (L.), which closely resembles the millipede in shape and dimensions but which does not secrete a repulsive odour in defence. We recorded and analysed a wide spectrum of behavioural responses including both those of avoidance and nonavoidance such as attempts to eat the arthropod. Behavioural responses were measured for 10 min upon first exposure to the millipede or wax moth. The procedure was repeated for 3 consecutive days. Upon exposure to a millipede, mice of both sexes showed a dramatic increase in the avoidance behaviour of digging. Moreover, millipedes were repulsive to mice and though they were sniffed frequently and sometimes caught, they were never eaten. In comparison, mice exposed to a wax moth almost always ate it. Sex differences emerged only for locomotion with female appearing to be more active. These results suggest that mice are able to discriminate between ethologically relevant odours and that the behavioural responses they display in this more natural context differ from those observed in response to odours of predators.

Ultrasonic vocalisation emitted by infant rodents: a tool for assessment of neurobehavioural development.

Ultrasonic vocalisations (USVs) emitted by altricial rodent pups are whistle-like sounds with frequencies between 30 and 90 kHz. These signals play an important communicative role in mother-offspring interaction since they elicit in the dam a prompt response concerning caregiving behaviours. Both physical and social parameters modulate the USV emission in the infant rodent. Recently, a more detailed analysis of the ultrasonic vocalisation pattern, considering the spectrographic structure of sounds has allowed a deeper investigation of this behaviour. In order to investigate neurobehavioural development, the analysis of USVs presents several advantages, mainly: (i) USVs are one of the few responses produced by very young mice that can be quantitatively analysed and elicited by quantifiable stimuli; (ii) USV production follows a clear ontogenetic profile from birth to PND 14-15, thus allowing longitudinal neurobehavioural analysis during very early postnatal ontogeny. The study of this ethologically-ecologically relevant behaviour represent a valid model to evaluate possible alterations in the neurobehavioural development of perinatally treated or genetically modified infant rodents. Furthermore, the role played by several receptor agonists and antagonists in modulating USV rate makes this measure particularly important when investigating the effects of anxiogenic and anxiolytic compounds, and emotional behaviour in general.

Psychosocial vs. "physical" stress situations in rodents and humans: role of neurotrophins.

Nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are well-studied polypeptide growth factors involved in the development and maintenance of specific peripheral and central populations of neuronal cells. In addition to its role as a neurotrophic agent, NGF controls very complex functions in vertebrate physiology. A variety of cells outside the nervous system are in fact able to synthesize NGF including epithelial cells, fibroblasts, lymphocytes, and macrophages. NGF target cells have been identified in the nervous, immune, and endocrine systems, suggesting that NGF may operate through multiple paths to ultimately regulate physiological homeostasis and behavioral coping. We used a mouse model of social stress to demonstrate that NGF levels increase both in plasma and in the hypothalamus following intermale aggressive interactions. The investigation has been extended to other species, including humans, to show that labour, lactation, and the anticipation of the first jump with a parachute also result in increased NGF plasma levels and in changes in the distribution of NGF receptors on lymphocytes. BDNF activation is caused by both physical and social stress events. The aim of this review is to (1) outline the current understanding of the roles of NGF and BDNF in stress-related physiological changes in vertebrates, in particular for physical vs. psychological stressors, which may activate both similar and different neurobiological pathways, and (2) summarize recent efforts to derive pharmacological strategies from the increasing body of BDNF and NGF neurobehavioral data.

Effect of hypergravity on the mouse basal expression of NGF and BDNF in the retina, visual cortex and geniculate nucleus: correlative aspects with NPY immunoreactivity.

We investigated the effect of hypergravitation on Nerve growth factor (NGF) and Brain-derived-neurotrophic factor (BDNF) expression in the visual cortex, geniculate nucleus (GN), and retina of adult male mice. The results showed that altered gravity causes an increase in NGF and BDNF in the visual cortex and GN which resulted to be associated with an up-regulation of cells immunoreactive to neuropeptide Y (NPY) in the visual cortex and GN. We also found a decrease in NGF, BDNF, and NPY in the mouse retina exposed to hypergravity. These findings suggest that alteration in gravitational environment differentially affects local neurotrophic factors and NPY expression. The possible functional significance of these observations is discussed.

Prolonged exposure to low doses of ozone: short- and long-term changes in behavioral performance in mice.

Two separate experiments were designed to assess the effects of ozone exposure on outbred CD-1 mice. In the first experiment, adult males were exposed continuously to O3 at 0, 0.3, or 0.6 ppm for 30 days and their behavior was assessed in a 5-min open-field test on exposure days 4 and 19 and on day 3 after the end of the exposure phase. In addition, mice performed a Morris water maze task from exposure day 24 to 28. In the second experiment, adult females were exposed from 30 days prior to the formation of breeding pairs until gestational day 17 to the same doses used in the first experiment. Litters were fostered at birth to untreated dams and neurobehavioral development of the offspring was investigated until adulthood. Specifically, somatic and sensorimotor development [postnatal day (PND) 2-20], homing performance (PND 12), motor activity (PND 21), passive avoidance (PND 22-23), water maze performances (PND 70-74), and response to a nociceptive stimulus (PND 100) were assessed. Results from both experiments confirm that exposure to O3 slightly but selectively affected neurobehavioral performance in rodents. Exposure to O3 did not grossly affect neurobehavioral development, whereas it consistently impaired reversal learning in the Morris water maze test in both prenatally and adult exposed mice. Moreover, longer latency to step-through in the first trial of the passive avoidance test and a decrease in wall rearing in the hot-plate test were recorded in O3 prenatally exposed mice. Except for the first open-field test, altered responses were observed only in animals exposed at the intermediate concentration of the gas. Adaptation and/or onset of compensatory mechanisms might be responsible for the lack of linear dose-response relationships.

Neurobehavioural effects of hypergravity conditions in the adult mouse.

To evaluate the behavioural response to a hypergravity condition in CD-1 mice, young adult subjects of both sexes were exposed to 2 g for a single 60 min rotational session. Motion sickness (MS) and ethological-type scoring of different activities were used to evaluate the behavioural response. Nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) levels were also assessed. Behavioural scores indicated a transient mild sickness associated with hypergravity, with reduction in spontaneous activity. In males kaolin consumption (a MS index) increased following rotation while females consumed more kaolin irrespective of whether they have been rotated or simply exposed to the noise and vibration of the rotational apparatus. In males, hypothalamic NGF levels were markedly increased after rotation while no major changes were observed in central BDNF expression. These results indicate mice may represent a suitable MS model.

Behavioural effects of endocrine disrupting chemicals on laboratory rodents: statistical methodologies and an application concerning developmental PCB exposure.

Appropriate behavioural tests and adequate statistical tools may help to establish the ED properties of a given compound by pointing out the alterations of selected behavioural endpoints. Frequently, laboratory collected data consist of frequencies and/or durations of specific items, and the analysis of variance (ANOVA) technique is performed to assess whether the investigated factors affect these behavioural endpoints. Moreover, when numerous aspects of behaviour are investigated simultaneously, Principal Component Analysis (PCA), a multivariate technique, may be very useful to reduce the overwhelming number of correlated original variables to a few orthogonal artificial variables (factors). Continuous Time Markov Chain (CTMC) models may be applied to analyse the time structure of a behavioural pattern when data consist of sequences of events and the time points at which they occur. Moreover, the Cox Proportional Hazard Model, a methodology originally developed for the analysis of failure time data, may help to evidence the effects of a given treatment on behavioural sequences when the assumptions of CTMC models are not fully satisfied. Analyses on data from mice of the outbred CD-1 strain (controls in a study of toxicity and exposed to PCB during development) are presented as examples to show how adequate statistical analyses and appropriate behavioural tests may reveal relevant effect of treatments otherwise not easily detected.

Ultrasonic vocalizations elicit orienting and associative reactions in preweanling mice.

On postnatal days (PND) 12 and 13, 90 male Swiss CD-1 mice were tested for orientation to 3 intensities of recorded ultrasounds while climbing an inclined wire grid surface. Motor responses and vocalization to replayed ultrasounds (55-75 kHz) of 20-, 40-, and 60-dB SPL indicated an intensity dependence. In Experiment 2, 138 pups were exposed to either contingent or noncontingent pairings of recorded ultrasounds of 55-75 kHz, averaging 40 dB, and mild inescapable footshocks, or taped vocalizations or footshocks only on PND 12, 14, or 16. At PND 18, subjects were tested for passive avoidance following exposure to the taped ultrasounds only upon entry into the dark side of a black-white compartment. Results suggested only overall, nonspecific effects of pretreatment to elicit responses antagonistic to motor activity. In Experiment 3, 36 pups at PND 15 were tested for passive avoidance with the ultrasound recordings of 40- or 80-dB onset upon entry to the dark compartment; a third group had no ultrasound exposure. A significant intensity effect confirmed that the ultrasounds had prepotent properties.

Ultrasonic vocalizations by infant laboratory mice: a preliminary spectrographic characterization under different conditions.

During the first 2 to 3 weeks of life, isolated neonatal mice emit ultrasonic vocalizations, with various conditions such as hypothermia or olfactory or tactile stimulation eliciting this behavior. Although it is known that pup vocalizations stimulate prompt expression of maternal behavior, the communicative role of infant ultrasonic calls is still a matter of investigation. A fine-grained spectrographic analysis of ultrasonic calls emitted by pups exposed to different conditions was performed. Forty 8-day-old outbred CD-1 mice (Mus musculus) were isolated from their mothers and littermates and randomly exposed to one of the following conditions: (a) odor from the nest, (b) social isolation, (c) low temperature-isolation, (d) tactile stimulation, or (e) odor from a conspecific adult male. Upon consideration of the spectrogram typology and emission frequency interval, it appears that the conditions under which vocalizations are emitted influence the sound characteristics of call production.

Neurobehavioral alteration in rodents following developmental exposure to aluminum.

Aluminum (Al) is one of the most abundant metals in the earth's crust, and humans can be exposed to it from several sources. It is present in food, water, pharmaceutical compounds, and in the environment, e.g., as a result of acid rain leaching it from the soil. Exposure to Al has recently been implicated in a number of human pathologies, but it has not yet been definitely proved that it plays a major causal role in any of them. In this paper we review the effects of developmental exposure of laboratory animals to Al salts as a model for human pathological conditions. The data presented show behavioral and neurochemical changes in the offspring of AL-exposed mouse dams during gestation, which include alterations in the pattern of ultrasonic vocalizations and a marked reduction in central nervous system (CNS) choline acetyltransferase activity. Prenatal Al also affects CNS cholinergic functions under Nerve Growth Factor (NGF) control, as shown by increased central NGF levels and impaired performances in a maze learning task in young-adult mice. The need for more detailed studies to evaluate the risks for humans associated with developmental exposure to Al, as well as the importance of using more than one strain of laboratory animal in the experimental design, is emphasized.

Methodological analysis in behavioral toxicology: an ethotoxicological approach.

A constraint in the development of laboratory animal models of human disease conditions is their applicability to the natural environment in which a given animal species evolved. The range of behavioral patterns that can be carefully assessed and quantified in the laboratory is sometimes limited. Although field studies reflect behavioral responses in natural settings, they may also have methodological limitations. Laboratory techniques are not applicable to wild species since natural conditions cannot be brought into a laboratory in an inexpensive or reliable way. However, it is possible to create near-natural settings which may not fulfill all the criteria of the actual context of evolution, but which can be controlled by the experimenter. We recommend an integrative style of approach considering laboratory constraints and, at the same time, the ecological niche in which a given behavioral pattern evolved. This type of ethological assessment may be useful when carrying out toxicological studies on both wild and laboratory mammals.