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J Bernard

Publications and source records attributed to J Bernard.

At least 91 records · Page 5Linked to original sources
PubMed1996

[Top-Forum: an interactive multimedia knowledge database to improve quality of care in pediatric oncology].

The treatment of pediatric cancer patients is characterised by complex and aggressive chemotherapy, difficult decision making, the numerous protocols available and the necessity of highly skilled caregivers. Quality of care is a major issue in all pediatric oncology units. We created an interactive multi-media database available to each caregiver to permit him/her to have easy access to information and thus increase his/her knowledge and participate in increasing their group's know-how. The computer database is available to all on a free-access basis in each ward. This is a novel approach to quality care, as it accords great importance to personal formation, allowing each caregiver to broaden his/her knowledge via easily obtained data which he/she can help enrich by permanent feedback. This database may become the backbone of department know-how.

Adolescent↗
PubMed1996

Tumoricidal potential of human macrophages grown in vitro from blood monocytes.

Adoptive transfer of activated autologous human macrophages obtained by in vitro differentiation of monocytes in culture has successfully undergone phase I clinical trials in patients with metastatic cancer. The efficacy of these autologous macrophages in the in vivo killing of human tumors has now to be demonstrated. GM-CSF was shown to increase the number of monocytes differentiating in culture into macrophages. These were then activated with IFN gamma which was reported as the best cytokine for tumoricidal activation of macrophages. The aim of this paper was to evaluate the in vitro tumoricidal activity of macrophages grown with GM-CSF and IFN gamma. This tumoricidal function was investigated by measurement of the cytolytic (chromium-51 release assay), cytostatic (anti-proliferative activity as measured by inhibition of [3H]-thymidine incorporation in two different assays) and cytotoxic (MTT assay) activities on two tumor cells lines, U937 and K562 (respectively highly sensitive and resistant to soluble TNF alpha). Our results demonstrated that GM-CSF-grown macrophages exhibited significant cytolytic, cytotoxic and cytostatic activities on U937 cells. These were partly enhanced by IFN gamma activation. In contrast, they had no lytic and lower cytotoxic and cytostatic activities on K562 cells, and these were not modified by IFN gamma activation. Our data provide valuable information for future in vivo studies using adoptively transferred autologous macrophages.

Adoptive Transfer↗
PubMed1995

Melittin increases AMPA receptor affinity in rat brain synaptoneurosomes.

Recent experimental evidence suggests that phospholipase-induced changes in binding properties of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) subtype of glutamate receptors account for the increase in synaptic response observed in long-term potentiation (LTP). In the present study, we report that treatment of rat telencephalic synaptoneurosomes with the bee venom peptide melittin, a potent activator of endogenous phospholipases, increased [3H]AMPA binding to the AMPA receptor. The action of melittin was concentration-dependent (EC50 value = 10 micrograms/ml) and did not require the presence of extracellular calcium. Saturation kinetic experiments revealed that the increase in [3H]AMPA binding produced by melittin was due to an enhancement in the affinity of the AMPA receptor, an effect markedly reduced by the phospholipase A2 (PLA2) inhibitor bromophenacyl bromide (BPB). In contrast to BPB, inhibitors of cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism did not interfere with the melittin-induced increase in [3H]AMPA binding. In neonatal synaptoneurosomes, the effect of melittin on [3H]AMPA binding was significantly reduced when compared to adult synaptoneurosomes, an effect which is consistent with the observation that LTP is not present in very young animals. The results indicate that activation of endogenous phospholipases may be an important mechanism in the regulation of AMPA receptor properties in LTP.

Aging↗
PubMed1995

Allergy to latex, avocado pear, and banana: evidence for a 30 kd antigen in immunoblotting.

Allergens of natural latex, latex gloves, avocado pear, and banana extracts were investigated by an immunoblotting technique in sera of patients experiencing associated latex and fruit allergies. Extracts were separated by sodium dodecyl-sulfate-polyacrylamide gel electrophoresis and electroblotted onto nitrocellulose. After incubation with patients' sera, IgE antibodies were revealed by a goat anti-human IgE alkaline-phosphatase conjugate. Seventeen serum samples from patients with well-documented latex allergy were studied. Among these patients, 10 demonstrated an allergy to avocado pear sometimes associated with banana. In sera from patients with latex and fruit allergy, prominent IgE binding was revealed at about 30 kd with latex and fruit extracts. Serum controls remained negative. Cross-inhibition of immunoblotting confirmed that this main allergen is linked to a common epitope present in latex and fruits. This must be related to clinical findings and previous observations of cross-reactivity.

Adult↗
PubMed1995

Topical treatment of onychomycosis.

Onychomycosis continues to be one of the more common foot problems encountered by podiatrists. Although a reliable cure is elusive, this article reviews several new agents that show some promise.

Administration, Cutaneous↗
PubMed1995

Molecular biology of fish viruses: a review.

The goal of this review is to present some of the recent molecular aspects in the fish virus studies. Although more than 50 different fish virus have been isolated and tissue-culture adapted, very few of them have been molecularly cloned and sequenced. Five virus families have been mostly studied: Birnaviridae, the prototype being the infectious pancreatic necrosis virus (IPNV), and the channel catfish virus (CCV) belonging to the Herpesviridae family. In the Iridoviridae family, the fish lymphocystis disease virus (FLDV) is the most studied. Retroviridae have been recently isolated and studied. The last family is the Rhabdoviridae, in which infectious hematopoietic necrosis virus (IHNV) and viral hemorrhagic septicemia virus (VHSV) have been extensively studied.

Animals↗
PubMed1994

In vitro steroidogenic effects of neuropeptide Y (NPY1-36), Y1 and Y2 receptor agonists (Leu31-Pro34 NPY, NPY18-36) and peptide YY (PYY) on rat adrenal capsule/zona glomerulosa.

The effects of neuropeptide Y (NPY1-36), of two analogs (Leu31-Pro34 NPY and NPY18-36) and of Peptide YY (PYY) on aldosterone and corticosterone secretions by freshly isolated rat adrenal capsule/zona glomerulosa preparations were investigated in vitro. NPY-related peptides (NPY1-36, Leu31-Pro34 NPY, NPY18-36), but not PYY, induced a dose-dependent release of aldosterone at concentrations ranging from 10(-8) to 10(-6) M. All the investigated peptides failed to significantly affect corticosterone secretion in concentrations ranging from 10(-10) to 10(-6) M (NPY1-36, NPY18-36), 10(-11) to 10(-6) M (Leu31-Pro34 NPY) or 10(-9) to 10(-6) M (PYY). Aldosterone secretion by this preparation of isolated adrenal capsule/zona glomerulosa was also significantly stimulated by high potassium levels (55 mEq) or by angiotensin II (AII) in concentrations ranging from 10(-8) to 10(-6) M. Moreover, NPY and Y1 or Y2 receptor agonists were positive aldosterone releasing agents as potent as AII. The present data support the existence of: (1) NPY binding sites of the Y3-like subtype, on rat adrenal capsule/zona glomerulosa. (2) A stimulatory effect of NPY on aldosterone production. So that the NPYergic innervation of the rat adrenal capsule/zona glomerulosa could be implicated in the multifactorial control of aldosterone production.

Aldosterone↗
PubMed1994

Neuropeptide Y (NPY)- and vasoactive intestinal peptide (VIP)-induced aldosterone secretion by rat capsule/glomerular zone could be mediated by catecholamines via beta 1 adrenergic receptors.

The effects of two Neuropeptide Y (NPY) analogs (Y1- and Y2-type) and vasoactive intestinal peptide (VIP) on both catecholamine (adrenaline and noradrenaline) release and aldosterone production by rat adrenal capsule/glomerular zone, have been investigated in vitro. The adrenal capsule/glomerular zones, collected from adult male rats, were incubated in a medium (Krebs-Ringer bicarbonate buffer supplemented with glucose and bovine serum albumin) containing or not one of the following synthetic peptides: human Leu31,Pro34-NPY (an agonist of the Y1-type receptors), human/porcine NPY18-36 (an agonist of the Y2-type receptors) and VIP at the concentration of 10(-7) M, associated or not with 10(-7) M atenolol (a beta 1 adrenergic antagonist) or ICI-118,551 hydrochloride (a beta 2 adrenergic antagonist). The two NPY analogs as well as the VIP stimulated the release of catecholamines and of aldosterone. The beta 1 adrenergic antagonist, but not the beta 2 one, which failed to affect basal aldosterone production when given alone, prevented NPY18-36-, Leu31,Pro34-NPY- or VlP-induced aldosterone secretion. Present data support the hypothesis that adrenaline and/or noradrenaline could mediate the effects of both NPY and VIP on aldosterone secretion via beta 1 adrenergic receptors; alternatively, the steroidogenic effect of NPY or VIP could be related to direct interaction between NPY- or VIP-specific binding sites, present on the capsule/glomerular zone of the rat adrenal cortex, and beta 1 adrenergic receptors. Then the NPYergic, VIPergic and catecholaminergic innervation of the adrenal cortex, previously characterized by immunohistochemistry, may be a potent stimulatory element in the nervous control of the aldosterone secretion.

Adrenal Glands↗
PubMed1994

Potassium-induced long-term potentiation in area CA1 of the hippocampus involves phospholipase activation.

Previous studies have shown that potassium-induced long-term potentiation (LTP) of the Schaffer collateral/commissural synapses in area CA1 of the hippocampus shares common properties with tetanus-induced LTP. In the present investigation, we performed electrophysiological and binding experiments on CA1 hippocampal slices to evaluate the location and nature of the changes underlying potassium-induced LTP. Paired-pulse facilitation, which represents an index of transmitter release, was markedly reduced by potassium-induced LTP. In addition, KCl-induced LTP was associated with an increase in 3H-AMPA ([3H]-amino-3-hydroxy-5-methylisoxazole-4-propionate) binding to CA1 synaptic membranes when measured 40 min after high-potassium exposure; however, no changes were detected in binding of an antagonist ([3H]-6-cyano-7-nitroquinoxaline-2,3-dione; 3H-CNQX) to AMPA receptors in slices expressing KCl-induced LTP. Administration of the phospholipase A2 (PLA2) inhibitor bromophenacyl bromide (BPB) prior to potassium application prevented LTP formation as well as the changes in paired-pulse facilitation and 3H-AMPA binding that characterized this type of potentiation. Taken together, these data indicate that potassium-induced LTP may be related to modifications in both pre- and postsynaptic properties and confirm the hypothesis that PLA2 activation is an important mechanism in long-term changes of synaptic operation.

Acetophenones↗
PubMed1994

The polymerase-associated protein (M1) and the matrix protein (M2) from a virulent and an avirulent strain of viral hemorrhagic septicemia virus (VHSV), a fish rhabdovirus.

We have cloned and sequenced the M1 and M2 genes of both a European (virulent) and a North American (avirulent) strains of viral hemorrhagic septicemia virus, an important fish pathogen. We also compared the transcription of the two genes following infection of cells and determined the phosphorylation status and detergent solubility of the two proteins. Despite a total lack of homology with any available rhabdoviral sequence, the two VHSV proteins share comparable structural features with their respective VSV and RV equivalents. Thus, they are likely to exert similar functions. The amino acid sequence of both proteins is highly conserved between the European and the North American strains, indicating a probable common origin. The most remarkable features are that the virulent and avirulent strains differ in the location of the transcription start signal for the M2 gene and in TX-114 detergent solubility of the M2 protein. However, these differences are not paralleled with any observable change at the levels of M2 gene transcription, M2 protein expression, or virion maturation. Thus, they are unlikely to play a significant role in determination of the virulent status.

Amino Acid Sequence↗
PubMed1994

Comparison of the bone mineral content of the lower limbs in men with ischaemic atherosclerotic disease.

In a previous study, the authors demonstrated that in 17 men with ischaemic atherosclerotic disease the bone mineral density (BMD) of the femoral neck was lower than in matched control subjects. The patients with arterial disease were thinner and were heavier smokers than the controls. Osteoporosis and arterial disease of the lower limbs were perhaps due to common risk factors: tobacco consumption and a low body build index. In order to demonstrate the direct effect of atherosclerosis on bone mineral content (BMC), the authors studied by dual-energy X-ray absorptiometry the BMC of both legs in 18 men presenting symptomatic arterial disease of the lower limbs quantified by measurement of distal systolic indexes by doppler ultrasonography. The mean BMC of the leg more severely affected by arterial disease was significantly lower than the mean BMC of the leg less affected by arterial disease (512 +/- 76 g versus 495 +/- 80 g: p = 0.003). In 13 of the 18 patients, the BMC was lower in the leg more severely affected by arterial disease; in 4 of 18 the difference between the BMC of the left and right legs was less than 1%, and in a single patient the BMC was higher in the leg more affected by arterial disease. Arterial disease of the lower limbs could lead to bone mineral loss.

Adult↗
PubMed1994

Modulation of the AMPA receptor by phospholipase A2: effect of the antidepressant trimipramine.

Previous results have shown that chronic administration of the antidepressant trimipramine prevents the formation of long-term potentiation in the rat hippocampus. In the present study, we compared the effects of chronic administration of trimipramine on the binding properties of hippocampal glutamate receptors and on the modulation of the DL-alpha-amino-3-hydroxy-5- methyl-isoxazolpropionic acid (AMPA) receptors by phospholipase A2 (PLA2). Whereas the binding characteristics of various agonist and antagonist ligands to the N-methyl-D-aspartate and the AMPA receptors were not modified by trimipramine treatment, there was a significant reduction in the increase in 3H-AMPA binding elicited by PLA2 treatment. Since activation of PLA2 has been reported to play a critical role in the formation of long-term potentiation, possibly mediated through a modification of the AMPA receptors, the results strengthen the hypothesis that PLA2-induced modification of 3H-AMPA binding is an important component of synaptic plasticity.

6-Cyano-7-nitroquinoxaline-2,3-dione↗