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Biomedical subjects

B Ferry

Publications and source records attributed to B Ferry.

At least 37 records · Page 2Linked to original sources
PubMed1999

Clenbuterol administration into the basolateral amygdala post-training enhances retention in an inhibitory avoidance task.

The present study examined the effects of post-training infusions of the specific beta2-adrenergic agonist clenbuterol into the basolateral nucleus of the amygdala (BLA), on inhibitory avoidance retention. Male Sprague-Dawley rats were surgically implanted with cannulae aimed at the BLA. Animals were microinfused with different doses of clenbuterol (from 1.0 to 1000.0 ng) immediately after training, and retention was tested 48 h later. Clenbuterol dose dependently affected retention performances. Whereas the 10.0-ng dose of clenbuterol induced a significant increase in the performances, the groups injected with the other doses (1.0, 100.0, and 1000.0 ng) of clenbuterol did not differ from the vehicle-injected animals. These findings, indicating that clenbuterol enhanced retention of the inhibitory avoidance task, are in agreement with previous evidence showing that the adrenergic system of the amygdala is involved in the modulation of memory. Moreover, our data support the hypothesis that the memory-modulating effect of the amygdala adrenergic system is mediated, at least in part, by the activation of the beta-adrenoceptors in the BLA. These findings provide further evidence that the BLA is an important brain region in integrating hormonal influences on memory storage.

Adrenergic beta-Agonists↗
PubMed1999

Functional interaction between entorhinal cortex and basolateral amygdala during trace conditioning of odor aversion in the rat.

In rats, conditioned odor aversion (COA) occurs only if the time interval separating the odor from the subsequent intoxication is very short suggesting that the memory trace of the odor is subject to rapid decay. Recent results from our laboratory have found that lesion of the entorhinal cortex (EC), and activation of the basolateral nucleus of the amygdala (BLA) rendered COA tolerant to long interstimulus interval. The present study examined whether the odor memory trace depends on the interaction between the EC and the BLA. Rats lesioned in the EC received infusions of muscimol (a GABA(A) receptor agonist) into the BLA immediately after the odor presentation during acquisition of COA. Injection of muscimol into BLA prevented tolerance of COA to long interstimulus interval induced by EC lesions. This suggests that EC modulates the short-term memory trace of the odor by controlling the GABAergic activity of the BLA during acquisition of COA.

Amygdala↗
PubMed1998

Facilitation of olfactory recognition by lateral entorhinal cortex lesion in rats.

An original olfactory recognition task was developed in order to examine the effect of lateral entorhinal cortex (LEC) lesion on olfactory mnesic processes. The task was based on the spontaneous exploratory behavior of rats toward odor sources. It consisted of a learning phase during which an odor was presented twice and in a recognition test, during which the same odor plus a new one was presented. The time rats spent sniffing the odor sources was measured. Olfactory recognition was identified by a short investigatory duration for the familiar odor as compared to a normal investigatory duration for the new odor during the test. The first three experiments aimed to validate the procedure. Experiment 1 was designed to show the decay of investigatory behavior caused by repeated exposure of the rats to one odor. Experiment 2 showed that normal rats display recognition when a short (5 or 40 min) pre-test delay was used, but not when a long pre-test delay (120 min) was used. Experiment 3 showed that FG7142, a well-known promnesic drug, enhanced the performance of the rats in this test as it allowed recognition at longer pre-test delays. The last experiment aimed at testing the effects of aspirative lesion of the LEC. Therefore, LEC-lesioned and sham-lesioned rats were submitted to variable pre-test delays. The experiment showed that an entorhinal lesion did not produce an impairment, but on the contrary facilitated olfactory recognition, as lesioned rats displayed recognition for delays at which sham-operated rats did not. These results show that LEC lesion apparently prolongs the duration of the olfactory mnesic trace. This effect might result from a modification of the functioning of structures innervated by the LEC. In this regard, it is noteworthy that LEC lesion produced a sprouting of septo-hippocampal fibers in the dentate gyrus of the hippocampus as assessed by acetylcholinesterase staining. Although the functional significance of this regrowth is not fully understood, the possible role of this sprouting should be considered.

Animals↗
PubMed1998

Lean tissue mass is a better predictor of bone mineral content and density than body weight in prepubertal girls.

PURPOSE AND METHODS: Body weight is the most extensively studied correlate of bone mass and is widely used as a covariate in statistical evaluations of bone mineral parameters. Lean tissue mass (LTM) also correlates with bone mass. We evaluated the correlations linking each of these two parameters with bone mineral content and bone mineral density in 41 prepubertal girls, including ten swimmers, 18 gymnasts and 13 nonathletes. Lean tissue mass, bone mineral content and bone mineral density were measured using dual-energy X-ray absorptiometry (Hologic QDR-1000/W; Hologic Inc., Waltham, MA, USA). Forward stepwise multiple regression was used to evaluate correlations linking bone mineral content or density (the dependent variables) to body weight or lean tissue mass (the independent variables). RESULTS: Body weight and lean tissue mass showed strong correlations with all bone mineral content and density measurements in the simple linear regression analysis, with lean tissue mass yielding the highest Pearson's correlation coefficients. In the multiple regression model, lean tissue mass consistently explained the largest proportion of the variance, whereas body weight had little influence or was eliminated from the model. The slopes of the regression lines of bone mineral content or density on body weight were significantly steeper in the subgroup of gymnasts (P < 0.001), whereas the slopes of the regression lines of bone mineral content or density on lean tissue mass were significantly less steep in the swimmers (P < 0.05). CONCLUSION: Our data indicate that lean tissue mass is a significant predictor of bone mass in prepubertal girls and explains a larger part of the variance of bone mineral content and density than body weight. Use of body weight as a covariate in studies of bone mineral density may lead to erroneous results in prepubertal girls.

Absorptiometry, Photon↗
PubMed1997

Bicuculline administration into basolateral amygdala facilitates trace conditioning of odor aversion in the rat.

This study investigated the effect of bicuculline methiodide (BMI) microinjection into basolateral amygdala (BLA) on conditioned odor aversion. Bilateral injections of BMI (39 or 59 pmol/0.2 microliter) or artificial CSF were done in the BLA 5 min after the presentation of the conditioned stimulus (water intake at an almond-scented tube). This was followed 30 min later by lithium chloride-induced toxicosis. Whereas under these experimental conditions control rats (CSF injected) did not develop a conditioned odor aversion, BMI-treated rats (59 pmol) did so, suggesting that the blockade of GABAA receptors facilitated this learning. This facilitation was unlikely due to an unconditioned action of BMI, as a group microinjected with 59 pmol of BMI but not intoxicated did not display conditioned aversion. This result suggest that blockade of the GABAA receptors can prolong the olfactory trace duration, making it accessible to association with delayed toxicosis. Combined with previous results, these data support the hypothesis that the GABAergic system of the basolateral amygdala exerts control over the duration of a short-term odor trace in our conditioned odor aversion paradigms.

Amygdala↗
PubMed1997

Intracellular cytokine expression in whole blood preparations from normals and patients with atopic dermatitis.

In recent years, the importance of characterizing the role of cytokines in a wide range of clinical conditions has resulted in development of new methods to assess cytokine expression in clinical samples. The use of anti-cytokine MoAbs and flow cytometry to detect cytokines intracellularly at the single-cell level has the potential to quantify cytokine production in different diseases. For this technique to be useful in a clinical setting, rapid throughput of clinical samples and a cheap, reliable assay would be required, therefore the development of the above technique using unseparated whole blood samples would be advantageous. Using this technique, only one study to date (Maino et al., 1996) has used unseparated whole blood as the source of cells for detecting intracellular cytokines. In clinical practice, whole blood may be optimal, since this most closely approximates conditions in vivo: as no purification of blood mononuclear cells is required, very little blood is needed to detect a number of cytokines simultaneously in various lymphocyte subpopulations, and the assay can be applied to samples from infants and children. In this study we describe an intracellular cytokine assay using unseparated whole blood from normals. In activated CD8- T cells, IL-2 and interferon-gamma (IFN-gamma) were optimally induced after 10 h stimulation with phorbol 12-myristate acetate (PMA)/ionomycin, and in CD8+ T cells IL-2 was optimally induced after 10 h and IFN-gamma after 6 h. The levels of IL-2 and IFN-gamma in CD8+ and CD8- T cells in four healthy individuals were consistent on four occasions over a 3-month period. In a large group of 34 normal subjects, there was considerable heterogeneity in CD3/IL-2+ (range 9.7-41.3) and CD3/IFN-gamma+ cells (10.1-44), expressed as a percentage of total lymphocytes. In patients with atopic dermatitis (n = 5) there was a significantly decreased percentage of CD3+/CD8+ peripheral blood T cells expressing IFN-gamma and an increased percentage of CD3+/CD8- T cells expressing IL-4 compared with non-atopic dermatitis controls (n = 5). Possible applications of this technique are discussed.

Adult↗
PubMed1997

Noradrenaline modulates glutamate-mediated neurotransmission in the rat basolateral amygdala in vitro.

The entorhinal cortex and the amygdala are interconnected structures of the limbic system in which paroxysmal activity occurs during temporal lobe epilepsy. Conflicting evidence shows that noradrenaline (i) inhibits the spreading to other parts of the limbic system of paroxysmal activity generated in the amygdala or the entorhinal cortex, but also (ii) increases glutamatergic transmission in the basolateral amygdala. Given our previous work on the inhibitory effect of noradrenaline on entorhinal cortex neurons, we developed an in vitro slice preparation to study the synaptic transmission in the basolateral amygdala and its modulation by noradrenaline. Noradrenaline reduced the fast excitatory postsynaptic potential (EPSP) by approximately 40% at 100 microM and the slow EPSP by approximately 50% at 50 microM. A similar effect was obtained with the alpha2-agonist UK 14304 at 100 and 50 microM respectively. In contrast, the beta-agonist isoproterenol increased the fast EPSP by approximately 40% at 100 microM and the slow EPSP by approximately 20% at 50 microM. Accordingly, the effect of noradrenaline on the EPSPs was blocked by the alpha2-antagonist yohimbine (10 microM) but not by the alpha1-antagonist prazosine (10 microM) and the beta-antagonist propranolol (10 microM). Noradrenaline (50-100 microM) was ineffective on most (14/16) of the isolated inhibitory postsynaptic potentials (IPSPs). These experiments provide evidence that noradrenaline inhibits the excitatory synaptic response of basolateral amygdala neurons. A pharmacological analysis revealed that the noradrenergic modulation of the excitatory transmission in the basolateral amygdala can be dissected into a predominant alpha2-adrenoreceptor-mediated inhibition and a beta-adrenoreceptor-mediated excitation.

Amygdala↗
PubMed1997

[Kinematics of the pelvic girdle and the thoracic and lumbar segments in the course of the lateral inclinations and rotations of the spine].

Physiological displacements of the trunk are the addition of these of the pelvic girdle and thoracic and lumbar spine segments. For a long time (3), this conjunction had been noticed but without numbered precisions. The purpose of this communication is to appreciate quantitatively, from a series of 16 subjects, the respective share of each components during lateral bending movements in the frontal plan and movements of rotation in the transverse plan. It results from this work that the pelvic girdle presents as reduced amplitude (4 degrees) in lateral bending on the other hand, displacement predominate to the level of thoracic spine (50 degrees). In rotation pelvic displacements are very important (30 degrees), while the spine so thoracic that lumbar has a weak participation (inferior to 5 degrees). Moderated abduction of hips increases by significant manner the motility of the pelvic girdle.

Adult↗
PubMed1996

Facilitation of conditioned odor aversion by entorhinal cortex lesions in the rat.

This study examined the role of the entorhinal cortex (EC) in conditioned odor aversion learning (COA). Lateral EC lesions did not impair but rather facilitated COA. In the experiments the delay separating the odor cue presentation from the subsequent toxicosis was varied during acquisition. EC-lesioned rats demonstrated COA for delays up to 2 hr, whereas sham-operated rats displayed COA only if toxicosis immediately followed the odor cue. This facilitation was not dependent on the intensity of the odor and corresponded to a facilitated long-delay learning. EC lesion did not affect conditioned taste aversion, confirming that the facilitation effect does not correspond to a general facilitation of conditioned aversion learning. Taken together, these results indicate that the removal of the EC may allow odor-toxicosis associations across longer delays by extending the duration of the olfactory trace.

Animals↗
PubMed1996

Inhibition of the transendothelial migration of human lymphocytes but not monocytes by phosphodiesterase inhibitors.

This study describes an in vitro model of peripheral blood mononuclear cell (PBMC) migration through human endothelial cells, held on polycarbonate inserts, which allows automatic differential counting of migrated cells as lymphocytes and monocytes. Using this system it was found that treatment of PBMC with the phosphodiesterase (PDE) inhibitors theophylline (at 1 and 10 micrograms/ml) and RO-20-1724 (at 1 microM) inhibited the migration of the lymphocyte component to 64.2+/-16.4%, 48.9+/-3.0% and 47.5+/-5.8% of the control values, respectively, while the migration of the monocytes component was largely unaffected. The PDE inhibitors needed to be present during the assay to inhibit migration, whereas pre-treatment of either the endothelium or the PBMC did not consistently effect lymphocyte migration. The drugs also inhibited the migration of lymphocytes through control inserts, either uncoated or coated with fibronectin, suggesting that some of the inhibition is an effect on lymphocyte motility rather than lymphocyte-endothelial interactions. Lymphocyte migration through fibronectin-coated filters was significantly enhanced compared with uncoated filters. Activation of the PBMC by anti-CD3 MoAb increased motility and migration by up to 300%. This migration appeared to be greatly inhibited by the PDE inhibitors, although the effect was complicated by problems of lymphocyte aggregation. This study provides a novel method of measuring mononuclear cell transendothelial migration, and suggests a possible role of PDE inhibitors in reducing this progress.

4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone↗
PubMed1996

[Preliminary analysis of the modifications of spinal curves, in extreme amplitudes, observed in rhythmic and athletic gymnastics].

Trained users of Rhythmic and Athletic Gymnastic, present kinetic spinal vast extents. Analysis, with pasted cutaneous markers, shows that, according to the codified movement, various segments of the vertebral column are requested and realized important displacements. Nevertheless, to have an homogeneous attitude, some subjects request more either lumbar or thoracic segments, of both. To prevent frequent spinal pain, it is important to realize a preliminary subject selection using their total spine and to improve protection by adapted gymnastic.

Adaptation, Physiological↗
PubMed1996

[Comparative study of static curves of the human spine in vivo during exercise and stretching in men and women].

Comparative study of static curves of the thoracic and lumbar spine in men and women has been realized under constraints of compression by weightlifting and elongation by exercise to parallel bars. In two athletic practices, curves decrease their arrow, ending to a straighter and more rigid column. This behavior expresses muscular actions. The greatest amplitude of displacement, observed in female series, shows lesser muscular forces in connection with a poor practice of exercises of body building.

Adaptation, Physiological↗
PubMed1995

Neuroanatomical and functional specificity of the basolateral amygdaloid nucleus in taste-potentiated odor aversion.

The present study aimed at documenting the neurobiological substrate of taste-potentiated odor aversion (TPOA) in the rat. The role of several temporal lobe structures in discriminative TPOA learning was questioned. The effects of excitotoxic lesions (ibotenate) of the basolateral amygdaloid nucleus, the central amygdaloid nucleus, the caudate putamen nucleus, and aspirative lesion of the entorhinal cortex were studied. The results show that only basolateral amygdaloid nucleus (ABL) damage impaired TPOA. This effect was selective of TPOA, since it spared conditioned taste aversion (CTA) and olfactory perception. In order to find out which process in TPOA requires normal functioning of the ABL, the effects of microinjections of a GABAA agonist (muscimol) into the ABL at various stages of the experiment were examined. The results show that application of muscimol during the acquisition, before or after the presentation of the odor-taste stimulus, impaired TPOA without affecting CTA. Contrastingly, application of muscimol before the test impaired neither TPOA nor CTA. These results suggest that ABL is involved in the acquisition but not in the retrieval of TPOA. The efficacy of muscimol microinjected after the presentation of the odor-taste stimulus further suggests that the deficit is not due to a sensory impairment but rather to the disruption of a memory process, critical for TPOA.

Amygdala↗
PubMed1995

Sexual behaviour in developing countries: implications for HIV control.

OBJECTIVE: To provide basic information on pre- and extramarital sex in the general population and other factors related to HIV transmission. DESIGN: Cross-sectional household survey in 18 countries of the developing world, mainly in Africa and Asia. RESPONDENTS: Representative samples of 1300-6995 individuals aged 15-49 years, interviewed in 1989-1993. METHODS: Face-to-face interviewing. RESULTS: We observed a huge variability between study sites, with the proportion of men reporting sexual contact outside regular partnerships in the last year ranging from 4 to 47%. Contacts with sex workers range from 1 to 25%. Women were much less likely to report non-marital sex than men. CONCLUSIONS: This first cross-cultural attempt to examine aspects of sexual lifestyles suggests that broad generalizations about multiple-partner sexual networking in particular regions are misleading. Gender, marital status, age and a few other demographic correlates were disclosed as powerful determinants of sexual behaviour, although the strength of associations varied greatly between specific locations. Condom use was very low in most study sites.

Adolescent↗
PubMed1991

[Utilization of health statistics in peripheral structures in developing countries].

Health information in developing countries serves mostly to diseases notification and activity registration, but rarely is it used for analyzing the health status of populations or the results of health intervention. Moreover, it is stored at a national level, mainly to fill monthly or yearly reports, and very seldom at a peripheral level where it would be probably more helpful. On the basis of experiences realized in Senegal and Nepal, we try to answer the two following questions: how to make health statistics utilizable, i.e. which criteria of relevance and quality recommend and how to utilize them concretely where they are produced, taking into account their well known limits?

Data Interpretation, Statistical↗
PubMed1987

Tumour aneuploidy, prognostic parameters and survival in primary breast cancer.

Cellular DNA content of primary tumours from 280 patients with operable breast cancer was determined by flow cytometry using nuclei from paraffin sections stained with DAPI, and 199 of these patients were followed for 8-13 years after surgery. Tumours from 67 patients have also been analyzed for their DNA content using single cell suspensions from fresh tumour tissue stained with mithramycin and ethidium bromide, and the results compared with those obtained from paraffin blocks of the same tumours. Overall 60% of the tumours contained cells with abnormal DNA content (DNA-aneuploid populations). Survival and disease free interval were not significantly different in patients with DNA-diploid and DNA-aneuploid tumours when analysed by Mantel's life table method. There was however, an early advantage for patients with DNA-diploid tumours: during the first 30 months after surgery DNA-aneuploidy was associated with higher rate of recurrence and shorter survival. DNA-aneuploidy was strongly related to histological grade. Thus 11/49 (22%) grade I, 60/102 (59%) grade II, and 96/129 (74%) grade III tumours were DNA-aneuploid. Although there was no significant difference in survival of patients with DNA-diploid and DNA-aneuploid tumours overall, there appears to be an unexpected association between DNA-aneuploidy and better survival in grade II patients (P less than 0.01); a similar trend was observed for grade I patients. Although the proportion of DNA-aneuploid tumours was similar in oestrogen receptor positive and negative tumours, DNA-aneuploidy was associated with lower levels of oestrogen receptors in comparison to DNA-diploid tumours. Comparison between the modal DNA values of fresh and paraffin embedded samples showed high rate of comparability (64/67, P less than 0.0001).

Aneuploidy↗