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Rationale: Corticotropin-releasing factor (CRF) and urocortin (Ucn) belong to the CRF-related family, share a high degree of structural homology and bind to CRF receptors. However, compared with CRF, Ucn was shown to display either weaker or similar anxiogenic-like effects in vivo., Objective: To compare the anxiogenic-like responses of rats injected intracerebroventricularly (ICV) with different doses of either rat/human CRF (r/hCRF) or rat Ucn (rUcn) at different intervals after injection., Methods: Rats were tested on three validated paradigms of emotional behavior [i.e. elevated plus-maze (EPM), defensive withdrawal (DW) and conflict test (CT)] 5 and 30 min after treatment., Results: In the EPM test only r/hCRF, but not rUcn, produced anxiogenic-like effects at the dose of 1.0 microg, when the peptides were injected 5 min before testing. At 30 min after injection, both peptides caused a significant reduction of open arms exploration, rUcn being effective at 0.01 microg. In the DW test both peptides were equally potent in decreasing the exploratory behavior and increasing the time spent in the chamber at the dose of 1.0 microg when tested 30 min after injection. In the CT both rUcn (0.25-1.0 microg) and r/hCRF (0.75-1.0 microg) decreased significantly the responding in the punished component. However, rUcn reduced food responding also in the unpunished component possibly due to its powerful anorectic activity., Conclusions: Comparison of anxiogenic-like activities of r/hCRF and rUcn at doses up to 1.0 microg revealed striking differential effects that depended on the time of testing after ICV peptide injection, and on the paradigm of anxiety used. These results suggest that the onset of r/hCRF and rUcn actions related to behavioral responses to anxiety is likely to depend on brain peptide-specific mechanisms including binding properties to CRF-receptors, differential distribution to specific functional brain sites and the distribution and effectiveness of binding-protein interactions.

A method was developed for the determination of rare earth elements (REEs) in urine with electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICPMS). The undiluted sample was directly injected into the graphite tube and trifluoromethane (Freon-23) was used as chemical modifier in order to reduce the vaporization temperature and the memory effect of most of the lanthanides. The detection limits were in the range 1-10 ng/L with relative standard deviation of 3-5% at concentration levels of 1microg/L, and less than 10-15% at 100 ng/L. Two different procedures, external calibration and a standard additions method, were evaluated to measure the concentration levels of lanthanides in the urine samples and the second procedure was considered to be the best choice for calibration in this work. The level of REEs in urine of 50 healthy volunteers was in the range 5-20 ng/L, above the detection limit of ETV-ICPMS., (Copyright 2002 John Wiley & Sons, Ltd.)

The present study provides evidence that the in vitro cultured fibroblast cell line from desmoid tumors differs from normal fibrobasts in its extracellular matrix (ECM) macromolecule composition and is modulated by treatment with toremifene, an antiestrogen that reduces tumor mass by an unknown mechanism. The results showed increased transforming growth factor-beta 1 (TGF-beta1) production, TGF-beta1 mRNA expression, and TGF-beta1 receptor number in desmoid fibroblasts compared with normal cells. As desmoid fibroblasts did not produce tumor necrosis factor-alpha (TNF-alpha) but were sensitive to it, which enhanced glycosaminoglycans (GAG) accumulation, we assessed the TGF-beta1 effects on TNF-alpha production by human monocytes. Our results showed TGF-beta1 significantly increased TNF-alpha secretion by monocytes. Toremifene mediated its effects in desmoid fibroblasts via an estrogen receptor-independent pathway. It inhibited GAG accumulation and the secretion of both latent and active forms of TGF-beta1 and had an inhibitory effect on TNF-alpha production by monocytes. Our results suggest that in reducing TGF-beta1 production by desmoid fibroblasts and TNF-alpha production by monocytes, toremifene may restore the balance between the two growth factors.

Objective: The present study investigated the effect of stimulating 5-HT(1A) receptors in the dorsal raphe on the impairment of spatial learning caused by intrahippocampal 7-chloro-kynurenic acid (7-Cl-Kyn) in naive rats and in rats familiar with the general requirements of the task., Methods: A week after implantation of cannulae to give access to the dorsal raphe (DR) and the CA1 region of the dorsal hippocampus, rats started their 5 days acquisition training on a two-platform spatial discrimination task in a water maze. On each acquisition day, WAY 100635 and 8-OH-DPAT alone or in combination were injected into the dorsal raphe (DR) 5 min before intrahippocampal injections of 7-Cl-Kyn which was given 10 min before the training session. Similar experiments were conducted in rats that had been familiarized with the general requirements of the task by pretraining them in the water maze in the absence of distal cues., Results: 7-Cl-Kyn (3 microg/microl), injected bilaterally in the CA1 region of the dorsal hippocampus, impaired choice accuracy with no significant effect on choice latency. Rats treated with 7-Cl-Kyn tended to spend more time swimming close to the pool walls and made more errors of omission than controls in the first two sessions. Administered into the DR, the 5-HT1A receptor agonist 8-OH-DPAT (1 microg/0.5 microl) had no effect on any parameter of rats' performance but antagonized the impairment of choice accuracy caused by intrahippocampal 7-Cl-Kyn. Injected into the DR, 1 microg/0.5 microl WAY 100635, a 5-HT(1A) receptor antagonist, had no effect on rats' performance or on the impairment caused by intrahippocampal 7-Cl-Kyn, but antagonized the effect of 8-OH-DPAT on the 7-Cl-Kyn-induced deficit. The non-mnemonic behavioral disturbances shown by naive rats treated with 7-Cl-Kyn were greatly reduced in pretrained rats which, nevertheless, showed a marked impairment of choice accuracy similar to that of naive rats. As in previous experiments, administration of 1 microg/0.5 microl 8-OH-DPAT in the dorsal raphe antagonized the impairment of choice accuracy caused by intrahippocampal 7-Cl-Kyn without any effect on other parameters of rats' performance., Conclusions: The results show that stimulation of presynaptic 5-HT(1A) receptors in the dorsal raphe counteracts the deficit in spatial learning caused by a reduced NMDA-mediated excitatory input on pyramidal cells in the hippocampus. The possible mechanisms and the importance of these findings for the symptomatic treatment of memory disorders in man are discussed.

The particle-bound organic compounds comprising n-alkanes, n-alkanoic monocarboxylic acids, polynuclear aromatic hydrocarbons (PAH) and nitrated polynuclear aromatic hydrocarbons (NPAH) were investigated in ambient air of the Ouargla city area (Algeria) during a short campaign performed in November 1999. The distribution profile of n-alkanes was consistent with the petrogenic origin of aerosols, suggesting that they were related to torching processes of crude oil refuses in the petroleum extraction field located not far from Ouargla. Instead, the presence of n-alkanoic acids of low molecular weight was indicative of microbial activity experienced by the site. PAH levels were low when compared to other polluted areas. The presence of 2-nitrofluoranthene and 2-nitropyrene, which can result from in-situ nitration of fluoranthene and pyrene, was concurrent with the substantial depletion of the most reactive among PAH, suggesting that photochemical processes influence the composition of the Saharian atmosphere.

The grazing pressure of the macrofaunal invertebrates associated with the biomass of Ulva rigida in the Venice lagoon, their species composition and relationship with environmental variables have been studied. Fifteen sampling campaigns were carried out during different seasons both in the central basin of the lagoon, dominated by macroalgae (especially U. rigida C. Ag.) and in the southern basin, prevalently populated by seagrasses (especially Zostera marina L.). Replicate experiments were conducted in the field by exposing Ulva fronds in net cages of 10 and 1 mm (control) mesh-sizes to allow or prevent grazer entrance. The grazing pressure was determined as Ulva growth rate difference in the cages. In the absence of invertebrate herbivores, Ulva exhibited per cent relative growth rates (%RGRs) ranging from 1.5 to 9.5% day(-1), whereas in their presence the %RGRs were significantly lower (from -2.5 to 3.4% day(-1)) and frequently negative, especially in the station dominated by macroalgae. In this area, peak grazing rates and macrofauna biomasses of up to 8.6% day(-1) and 1,480 g m(-2) fwt (84.4 ash-free dry weight), respectively, were found. On the whole, during in field experiments in the Ulva-dominated station, herbivores removed an amount of biomass whose percentage ranged from 59 to 165% (mean: 103%) of the biomass yield (grazers excluded) found in the cages. These results suggest the possibility that grazers could act as an important factor affecting Ulva production in the Venice lagoon. Macrofauna populations were analysed by means of multivaliate techniques applied to biological variables only and biological and environmental variables together. Data of individual abundance, after a log(x + 1) transformation and the calculation of the Bray-Curtis matrix, were classified using the Cluster Analysis and ordinated by means of the Non-Metric Multidimensional Scaling (MDS) technique, in accordance with the strategies used in the study of multispecies distributions. Finally, biological and environmental variables were analysed together by means of correlation matrices and the Principal Component Analysis.

Genomic clones of the human GM2 activator protein have been isolated and analyzed. The 5' region of the gene demonstrated promoter activity as ascertained by its ability to drive luciferase gene expression in transfected COS cells. This sequence contains GC rich region and several putative promoter elements were present, including Sp1, AP2, cAMP-responsive element, and B-cell-specific activating protein. Analysis of tissue distribution of the GM2 activator protein gene revealed tissue-specific variations in transcript levels. Placenta, bone marrow, mammary gland, bladder, lymph node, and spleen had the highest mRNA levels.

1. We studied the effects of low doses of 8-OH-DPAT, a 5-HT(1A) receptor agonist, on the impairment of spatial learning caused by scopolamine injected into the CA1 region of the dorsal hippocampus of rats performing a two-platform spatial discrimination task. 2. Bilateral injections of 4 microg (in 1 microl) of scopolamine into the CA1 region of the dorsal hippocampus 10 min before each training session impaired choice accuracy with no effect on choice latency and errors of omission. 3. Administered subcutaneously 20 min before each training session, 8-OH-DPAT 10 and 30 (but not 3) microg kg(-1) did not modify choice accuracy but prevented the impairment by intrahippocampal scopolamine. 4. Injection of 1.0 microg (in 0.5 microl) of WAY 100635, a 5-HT(1A) receptor antagonist, into the dorsal raphe 5 min before scopolamine had no effect on choice accuracy and latency or errors of omission and did not modify the effect of scopolamine, but completely antagonized the effect of 10 and 30 microg kg(-1) 8-OH-DPAT on scopolamine-induced impairment of choice accuracy. 5. The results confirm previous findings that stimulation of presynaptic 5-HT(1A) receptors in the dorsal raphe attenuates the deficit of spatial learning caused by blockade of cholinergic excitatory input on hippocampal pyramidal cells. 6. Drugs that stimulate presynaptic 5-HT(1A) receptors such as 5-HT(1A) receptor partial agonists may be useful in the symptomatic treatment of human memory disturbances associated with loss of cholinergic innervation to the hippocampus.

Spectral analysis may allow the evaluation of (baroreflex) gain and phase between the RR interval and systolic pressure oscillations synchronous with respiration but, unlike baroreflex gain, the determinants of phase are not completely understood. We evaluated the correlates of spectral phase in 92 healthy subjects (44 men) aged 10-80 years. To do so, the cardiorespiratory signals during paced breathing at 16 breaths/min were continuously recorded and analyzed. In addition, respiratory sinus arrhythmia and baroreflex gain (two indices of cardiac vagal activity) and phase were calculated by using an autoregressive spectral technique. At univariate analysis, the phase correlated with age (r = 0.48, P < 0.001), the RR interval (r = 0.32, P < 0.01), respiratory sinus arrhythmia (r = -0.3, P < 0.01), baroreflex gain (r = -0.29, P < 0.01), and body mass index (r = 0.25, P < 0.05). At multivariate analysis, age was the most important physiological correlate of phase, accounting for 23% of interindividual phase variation. Cardiac vagal activity measures (which were higher in women than men) and the RR interval were also significant independent correlates of phase. We conclude that in addition to the RR interval and cardiac vagal activity, age has a significant impact on the phase relationship between respiratory related oscillations of the RR interval and systolic blood pressure. This spectral measure may contain additional information concerning the mechanisms that influence cardiovascular rhythms.

1 The effect of S 15535 (4-benzodioxan-5-yl)1-(indan-2-yl)piperazine), an agonist at presynaptic and antagonist at postsynaptic 5-HT1A receptors, on the impairment of spatial learning caused by intrahippocampal scopolamine in a two-platform spatial discrimination task was studied. 2 Scopolamine (4.0 microg microl-1), injected bilaterally into the CA1 region of the dorsal hippocampus 10 min before each training session, impaired choice accuracy with no effect on choice latency and errors of omission. 3 Administered subcutaneously 30 min before each training session, S 15535 1.0 (but not 0.3) mg kg-1 did not modify choice accuracy but prevented its impairment by intrahippocampal scopolamine. 4 WAY 100635, a 5-HT1A receptor antagonist, injected into the dorsal raphe at 1.0 microg 0.5 microl-1 5 min before scopolamine, had no effect on choice accuracy and latency or errors of omission and did not modify the effect of scopolamine but completely antagonized the effect of S 15535 (1.0 mg kg-1) on scopolamine-induced impairment of choice accuracy. 5 The results confirm a previous report (Carli et al., 1998) that stimulation of presynaptic 5-HT1A receptors in the dorsal raphe counteracts the deficit caused by intrahippocampal scopolamine, probably by facilitating the transfer of facilitatory information from the entorhinal cortex to the hippocampus. 6 Drugs that stimulate action on presynaptic 5-HT1A receptors, such as S 15535 and other partial 5-HT1A receptors agonists, may be useful in the symptomatic treatment of human memory disturbances associated with loss of cholinergic innervation to the hippocampus.

Previous studies have found that respiratory variations of ventricular response in atrial fibrillation are infrequent and inconsistent. This asynchrony between heart rate and respiration may characterize the physiological mechanisms coupling heart rate and systolic blood pressure oscillations in the respiratory band. The aim of this study was to evaluate whether synchronous variations in systolic blood pressure and respiration depend on a simultaneous change in heart rate. Univariate and bivariate spectral analyses were made of the R-R interval, systolic blood pressure, and respiratory signals during controlled respiration (16 breaths/min) in 24 patients with atrial fibrillation before and after efficacious electrical cardioversion and in 24 age- and sex-matched control subjects. During atrial fibrillation, the spectral coherence between respiration and heart rate was low (0.18+/-0.03), but there was a high level of coherence between respiration and systolic blood pressure (0.67+/-0.05). After cardioversion, the coherence between respiration and heart rate increased to 0.86+/-0.04, whereas the geometric mean values of the concomitant respiratory systolic blood pressure oscillations decreased by 72% (from 21.1 to 5.9 mm Hg(2), P<0.001), which was similar to that observed in the control group (5. 7 mm Hg(2)). These results confirm the inconsistent effect of respiration on heart rate response during atrial fibrillation and demonstrate that respiratory sinus arrhythmia is not a prerequisite for systolic blood pressure oscillations but may play an antioscillatory role in respiratory systolic blood pressure variability, which is probably mediated by arterial baroreflex mechanisms.

Dopamine neurotransmission is an important neuropharmacological component of cocaine self-administration in rodents. Terguride is a prototype drug belonging to a recently characterized class of compounds, dopamine partial agonists, which appear to possess a unique pharmacological profile in altering dopamine neurotransmission, where these drugs act as antagonists in conditions of high dopaminergic tone. The aim of the present study was therefore to test the effects of systemic administration of terguride in rats self-administering cocaine intravenously. The different aspects of cocaine self-administration examined after treatment with terguride were (a) the acute reinforcing properties of cocaine in rats exposed to limited-access self-administration of cocaine, (b) a full cocaine dose-effect function, (c) the reinforcing properties of cocaine as measured by a progressive ratio schedule and (d) the ability of terguride to maintain self-administration by itself. Terguride (0.025-0.4 mg/kg i.p.) significantly and dose-dependently reduced the acute reinforcing properties of cocaine as measured by an increase in responding for a single training dose of cocaine and a reduction of the inter-reinforcement interval. In addition, terguride (0.2-0.4 mg/kg) shifted the entire cocaine dose-effect function to the right, thus showing an antagonism of the reinforcing properties of cocaine independent of response rate. Moreover, in rats trained to self-administer cocaine on a progressive ratio schedule, terguride reduced the maximum fixed ratio ("breaking point") for cocaine reinforcement, also suggesting a decrease in the reinforcing properties of cocaine. Finally, in rats trained to self-administer cocaine terguride did not substitute for cocaine, thus indicating that terguride does not maintain intravenous self-administration by itself.

Objective: Determination of the urinary levels of 2.5-hexanedione (2,5-HD) was performed in subjects belonging to the Italian general population to define the reference value for this metabolite., Materials and Methods: Urine samples were collected from 123 healthy Italian subjects who had not been occupationally exposed to n-hexane or methyl-n-butyl ketone (60 men and 63 women; 53 living in urban areas and 70 living in rural areas; 36 smokers and 87 nonsmokers; 65 aged above 35 years and 58 aged below 35 years). The determinations were performed by a gas chromatography method using a flame ionization detector (FID). A quality-control step was realized by analysis of 78 of these samples by high-performance liquid chromatography (HPLC) with UV detection., Results and Discussion: The distribution of 2,5-HD concentration was log-normal and the corresponding centiles at the 95% confidence interval were as follows: the 50th centile, 0.270 mg/l for men and 0.191 mg/l for women; the 75th centile, 0.352 and 0.330 mg/l, respectively, for men and women; and the 95th centile, 0.762 and 0.582 mg/l, respectively, for men and women. The reference value, calculated as the upper unilateral 95% tolerance interval at 95% of confidence, was 0.795 mg/l for men and 0.627 for women.

Background: Depressed baroreflex sensitivity obtained by means of a phenylephrine test plays a prognostic role in patients with a previous myocardial infarction. Our purpose was to evaluate the correlation and agreement between the baroreflex sensitivity obtained with phenylephrine and that obtained by two noninvasive methods: the alpha-index and sequence analysis., Methods and Results: The alpha-index was measured by means of the spectral analysis of RR and systolic blood pressure variabilities in both the high- and low-frequency bands; sequences were identified from simultaneously recorded time series in which the RR and systolic blood pressure concurrently increased or decreased. Noninvasive baroreflex sensitivity tests were performed during both spontaneous and controlled respiration. Fifty-two consecutive patients with recent myocardial infarction underwent the analyses. Although the correlations between phenylephrine and either of the noninvasive methods were always significant, those found during controlled respiration had the highest r values (r=.70). However, the limits of agreement calculated by means of the Bland and Altman method were wide for both noninvasive methods., Conclusions: The results obtained by means of noninvasive baroreflex sensitivity assessments should not be used in clinical practice as an alternative to those obtained by the phenylephrine method.

The effects of a blockade of nitric oxide synthesis were studied in rats trained to self-administer cocaine intravenously. Pretreatment with Ng-nitro-1-arginine methyl ester (l-NAME; 10-50 mg/kg, intraperitoneally, twice daily for 4 days), significantly and dose-dependently suppressed the maintenance of intravenous cocaine self-administration and the absolute reward magnitude of cocaine. These results suggest that nitric oxide may play a role in cocaine abuse and dependence.

Zein messenger RNAs from maize endosperm were purified by successive oligo(dT)-cellulose chromatography and sucrose gradient centrifugation. Polyacrylamide gel electrophoresis under denaturing conditions revealed the presence of two size classes of zein messenger RNAs of Mr 3.5 x 10(5) and 4.10 x 10(5). The mRNA was shown to synthesize the major zein polypeptides, to have a base composition characteristic of a poly(A)-containing RNA and to be transcribed by reverse transcriptase into complementary DNA. The r0t1/2 of the hybridization curve of cDNA hybridized to an excess of mRNA was shown to be 7 x 10(-2) M . s indicating that about 15 non-cross-hybridizing sequences are present in the zein mRNA preparations. The kinetics of cDNA annealing with an excess of maize DNA from 2 n cells suggest a ten-times reiteration of each mRNA sequence. This result is confirmed from saturation experiments, where in cDNA excess to DNA, the number of zein genes per haploid maize genome was estimated as about 120 copies. Similar experiments carried out on DNA from normal and mutant endosperms (3n cells) indicate the absence of large amplifications or deletions of zein genes in the tissue devoted to zein synthesis.