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Y Prigent

Publications and source records attributed to Y Prigent.

35 records · Page 2Linked to original sources
PubMed1994

[Reflections on the management of dysthymia and chronic depression].

The authors points out the more and more commonly admitted importance of mood disturbances that do not result from major dysthymic states, whether from dysthymies or depressives personalities. He notices that the treatment of such states according to an almost general consensus requires a prescription for a very long anti-depressive treatment. He underlines the problems that can be caused by a long intake of medicines, from a theoretical point of view, concerning psychopathologic reference models as well as from a practical point of view concerning the observance of medicine intake. He suggests some therapeutic axes. Concerning chemotherapy, he suggests choosing a molecule with a serotoninergic tropism that is well tolerated and favours intra-psychic elaboration as well as respects cognitive potentialities. From a therapeutic point of view, he recommends a support that avoids excessive mentalisation, blabbering and obsessive harking but that on the contrary favours the expression of the affect and the shifting of representations on the widened model of psychotherapy inspired by psychoanalysis.

Antidepressive Agents↗
PubMed1993

Immunoelectron microscopic distribution of actin in the spermatids and epididymal spermatozoa of the mouse.

The distribution of actin in spermatids and epididymal spermatozoa of the mouse was examined by electron microscopy with immunogold procedures using two monoclonal antiactin antibodies. Actin was identified by immunoblotting of proteins extracted from either whole spermatozoa or tail fractions. In round spermatids, actin immunolabeling was detected in the subacrosomal space. Labeling increased during the elongation phase, and then decreased and completely disappeared before spermiation. No labeling was found in epididymal spermatozoa and residual bodies. Our results suggest actin redistribution or the absence of G-actin from the head to the flagellum in mature murine spermatids, as previously shown in other studies in various mammals.

Actins↗
PubMed1992

Influence of methoxy and nitro groups in the oxidative metabolism of naphtho[2,1-b]furan.

In the present study, we have investigated the role of methoxy and nitro groups in the oxidative metabolism of naphtho[2,1-b]furan. Hepatic microsomes were used to investigate the aerobic metabolism of naphtho[2,1-b]furan (compound A), 2-nitro-naphtho[2,1-b]furan (compound B) and 7-methoxy-naphtho [2,1-b]furan (compound C) and comparison of the metabolites formed was made using HPCL analysis and NMR, mass and UV-visible spectrometry. The different metabolic pathways investigated were compared with the previously reported metabolism of 7-methoxy-2-nitro-naphtho[2,1-b]furan (compound D). Naphtho[2,1-b]furan yield metabolites of both the furan and benzene rings, while metabolites formed from 7-methoxy-naphtho[2,1-b]furan and 2-nitro-naphtho [2,1-b]furan were derived entirely as a result of enzymic attack on the first benzene ring.

Animals↗
PubMed1991

Tricholongins BI and BII, 19-residue peptaibols from Trichoderma longibrachiatum. Solution structure from two-dimensional NMR spectroscopy.

Two nonadecapeptides, tricholongins BI and BII, which display antifungal and antibacterial activities, have been isolated from in vitro cultures of the fungus Trichoderma longibrachiatum. The peptides were separated by reversed-phase HPLC; their amino acid compositions were determined by gas chromatography and their sequences by positive-ion fast-atom-bombardment mass spectrometry and high-field NMR. These linear peptides, containing mainly hydrophobic L-amino acids, 8-9 2-aminoisobutyric acid residues and exhibiting an acetylated N-terminal residue and an amino alcohol C-terminal leucinol belong to the peptaibol class. The methanol solution structure of tricholongins BI and BII has been investigated using both one- and two-dimensional NMR techniques. The total 1H-NMR and 13C-NMR assignments are given. By a combination of the 3JNH,C alpha H coupling constant values, temperature coefficients of the NH and CO groups, amide hydrogen/deuterium-exchange rate measurements and NOE data, a secondary structure for tricholongins in solution has been proposed. Both peptides adopt a similar alpha-helical conformation with a hinge around Pro13 resulting from two 3(10) bonds. The results suggest that the N-terminus contains mixed alpha/3(10) bonds. The membrane permeability modifications induced by tricholongins have been assayed by the use of liposomes composed of egg phosphatidylcholine with 20-30% cholesterol. The peptide-induced leakage of an entrapped fluorescent probe has been followed by fluorescence spectroscopy. In a concentration range of 0.13-0.31 microM, tricholongins induce the leakage of 50% of the entrapped material in 20 min.

Amino Acid Sequence↗
PubMed1989

[Long term depression].

Our practice, in a unit of treatment of dysthymic state being confronted with problems of relapses and recurrences, we have questioned the therapeutic strategies in the long run and their possible assessments. After recalling conceptual and methodological reference about relapses, recurrences and therapeutic assessment, we propose the methods and first results of a retrospective naturalistic study over a period of three years of practice in our treatment unit including 994 cases. We bring out, as soon as the first major depressive episode occurs, a strategy that aims at setting up a therapeutic proceeding tending to treat, beyond the dysthymic episode, the obsessional pre and post-morbid "locks" which seem to "make the bed" of many relapses and recurrences. In this prospect, the interest of serotoninergic molecules with double polarity, anti-depressive and anti-compulsive, is emphasized.

Depressive Disorder↗
PubMed1988

[The experimental pathogenic effect of Spiroplasma isolated from mosquitoes on the hatching of Aedes aegypti ova and the growth of larva hatched from these eggs].

The authors did study the experimental effects on Aedes aegypti ova of different Spiroplasma strains, isolated from mosquitoes in French Savoy and in Taiwan. The SP7 strain, from Armigeres subalbatus (Taiwan), demonstrates a true pathogenic effect on the larval evolution, without sex ratio modifications, nor bacterial transmission to the adult mosquitoes. The authors present their results and emphasize the difficult use of Spiroplasmas sp.

Aedes↗
PubMed1983

Simple preparation of 1,2-dipalmitoyl-sn-glycero-3-phosphoric acid and deuterated choline derivatives.

Analytically pure 1,2-dipalmitoyl-sn-glycero-3-phosphoric acid was prepared in gram amounts, using a simplified version of a previous procedure. The main step, enzymatic cleavage of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine with freshly extracted phospholipase D, was performed in the presence of chloroform and the crude phosphatidic acid was purified by silica gel column chromatography. The interest of the method was illustrated by the synthesis of two dipalmitoyl phosphatidylcholines selectively deuterated on the polar headgroup.

Deuterium↗
PubMed1981

Cation permeability induced by two aromatic heptaenes, vacidin A and candicidin D on phospholipid unilamellar vesicles.

The cationic permeability induced by two aromatic heptaenes, vacidin A and candicidin D, has been studied on egg yolk L-alpha-phosphatidylcholine single walled vesicles as a function of cholesterol and ergosterol concentration. For comparison amphotericin B and nystatin were also tested. Vacidin A and candicidin D elicit cation permeability in both types of vesicles in the same concentration ranges and exhibit only quantitative differences in cholesterol and ergosterol vesicles. The active concentration range is of the same order of magnitude as the active concentration range of amphotericin B, at variance with what is obtained on biological cells. This difference is interpreted in term of mechanism of action of polyene on both biological and model membranes.

Amphotericin B↗
PubMed1978

[Reflections and perspectives on institutional therapy in neurotic depressions].

We have found that an institutional psychothérapy for neurosis could benefit by using elements of the work of Winnicott as well as of the bioenergetic and existential movements. This corresponds to a more and more explicit request from depressed patients who are expecting more from their stay in the hospital than simply to recharge their energy. We thought that our department, because of its size, type of patients, staff and its own orientation would be well adapted to an experience of this kind. In our hospital we try to facilitate in the patient: --regressive experiences; --the perception of "being"; --the symbolic and emotional feeling of the reality of time and place and particularity of the body; --the capacity to repair himself; --playing in the sense of Winnicott: playing with the in and the out (of onesself), the positions of the body, verbal play, play of alternation. --Centering on desire on the interior space, with the capacity to be "alone in the presence on another"; --the discovery of "responsability" and "compassion", also in the sense of Winnicott. We must take into consideration that in order to benefit from this type of therapy, there must be a good enough integration and a pain that is authentically experienced, that is, not acted out, not sutured, and without too many defenses. The results can be appreciated only very subjectively, since improvement is of a qualitative order, in the area of development of being serious existentially. We can perhaps envisage another future for the depressed patient than the interminable repetition of relapses or of beign treated indefinitely. This consists of discovering another way of being, more global, more serious, more authentic (real-self), considering the difficulties involved in the engagement of the realself in an already structured existence.

Adjustment Disorders↗
PubMedDate not supplied

Immunoelectron microscopic visualization of intermediate basic proteins HPI1 and HPI2 in human spermatids and spermatozoa.

In humans, intermediate basic proteins HPI1 and HPI2 are considered as common precursors of the P2 protamine family, according to data provided by structural studies of these proteins. The occurrence and fate of proteins HPI1 and HPI2 were investigated in nuclei of human spermatids and spermatozoa by means of immunoelectron microscopy. A specific polyclonal antibody against a synthetic peptide overlapping the N-terminus of HPI1 and HPI2 was prepared and used to detect these proteins on sections of testis and ejaculated sperm. A quantitative analysis of labelling density was performed on micrographs using an interactive image analysis system. The first signs of labelling of intermediate basic proteins appeared in spermatid nuclei at steps 4-5 of spermiogenesis, i.e. during the chromatin condensation process. The nuclear labelling density strongly increased in elongating spermatids (steps 5 and 6) and then sharply decreased from step 6 to step 8 of spermiogenesis. However, weak labelling persisted in the nuclei of mature spermatids and ejaculated spermatozoa. The present results show that the intermediate basic proteins HPI1 and HPI2 are synthesized in large amounts in human spermatids during elongation phase and disappear almost totally in mature spermatids when deposition of protamines is completed in condensed nuclei.

Amino Acid Sequence↗
PubMedDate not supplied

[Elaboration, perlaboration, in the course of antidepressant chemotherapy].

From the results of an 8 years naturalistic and pragmatical study in a Care Unit for Patients with Dysthymic Disorders at Hôtel-Dieu-Pont-L'Abbé (France), the author points out that there is during long term antidepressive therapies a facilitating action in the psychoaffective elaboration and maturation. The author stresses the importance of agonistic molecules in the serotonin which seem to favour a psychological "working-through" probably because of the lifting of compulsive-obsessive mechanisms present in chronic an residual depressions. The authors underlines the importance of naturalistic and pragmatical studies as an alternative or as a complement to protocolar and controlled studies which are often biased. These biases are increased because of complicated psychometrics and by recent legal measures which tend to lessen the clinical credibility of these "controlled" studies.

Antidepressive Agents↗