Biomedical subjects

P Rouget

Publications and source records attributed to P Rouget.

At least 19 recordsLinked to original sources

PubMed2005

Subcellular localization of neural-specific NPDC-1 protein.

NPDC-1 is a gene specifically expressed in neural cells when they stop to divide and begin to differentiate. Immunocytochemical study analysis of differentiated PC12 cells transfected with NPDC-tag vectors showed that NPDC-1 is transported in vesicles from the Golgi apparatus to the cell membrane and is then likely internalized into endosomes. The protein colocalized, at least partially, with synaptic vesicle proteins: synaptophysin, synaptobrevin 2, and Rab3 GEP (Rab3 GTP/GDP exchange protein). Moreover, subcellular fractionation of rat brain showed that crude synaptic membrane and crude synaptic vesicle fractions were enriched in NPDC-1. Although NPDC-1 bound Rab3 GEP in vitro, it seems unlikely to be involved in Ca2+-dependent exocytosis and, thus, in synaptic vesicle trafficking.

Animals↗

PubMed2005

[Self-treament for bulimia on the Internet: first results in Switzerland].

Adolescents with bulimia have become a major clinical problem with increasing health concern. A self-help guide, inspired by the cognitive and behavioral therapy, was developed in response to the growing demand for treatment. On the behalf European research fund "SALUT", the guide was implemented on the Internet. The first swiss results are very encouraging; particularly concerning symptoms and the questionnaires (SCL-90 and EDI-2).

Adult↗

PubMed2004

Functional analysis of the NPDC-1 gene.

Mouse NPDC-1 (Neural Proliferation Differentiation and Control-1) is specifically expressed in neural cells when they stop dividing and start to differentiate. The NPDC-1 protein has been shown to interact with the E2F1 transcription factor, D-type cyclins and Cdk2. Immunocytochemical studies and subcellular fractionation of rat brains disclosed a partial colocalization of NPDC-1 with synaptic vesicle proteins, suggesting additional functional interactions. Here, we report the characterization of the mouse and human genes that were found to display very similar structures. We mapped the human gene to chromosome 9q34.3. No obvious pathological defect has been previously linked to this region. In order to gain further insights into its function(s), we generated null mice for the NPDC-1 gene. We did not detect any macroscopic phenotypical defect. Analysis of the upstream sequence of the mouse NPDC-1 gene delineated two regions involved in its negative and positive transcriptional regulation. Evidence for the regulation of NPDC-1 by Krox family transcription factors is presented.

Animals↗

PubMed2000

NPDC-1, a regulator of neural cell proliferation and differentiation, interacts with E2F-1, reduces its binding to DNA and modulates its transcriptional activity.

We have previously identified NPDC-1, a neural factor involved in the control of proliferation and differentiation, and we have shown that the stable introduction of NPDC-1 into transformed cells down-regulates cell proliferation both by increasing the generation time and by suppressing transformed properties. The data presented here indicate that, in vitro, NPDC-1 is able to interact with the transcription factor E2F-1 and some cell cycle proteins, such as D-cyclins and cdk2. In addition, two-hybrid experiments in mammalian cells show that the interaction between NPDC-1 and E2F-1 can also occur in vivo. This interaction reduces the binding of E2F-1 to DNA and its transcriptional activity. Taken together, the data suggest that NPDC-1 could influence cell cycle progression and neural differentiation through its association with E2F-1.

Animals↗

PubMed1999

"Weight loss preoccupation in aging women": a review.

Preoccupation with body weight leading to frequent dieting has been found to be common in young women of developed countries. Little is known however about body image preoccupation or the prevalence of dieting for weight control purposes in elderly women. The few available reports suggest that preoccupation with weight remain high in elderly women and that pressure to be thin drives normal weight older women to recurrent dieting. After a reminder of the nutritional vulnerability of the elderly recommendations to the health care professionals and health authorities are provided. An increased awareness of eating habits and weight preoccupation in elderly women is needed, since attitudes towards weight may influence the effectiveness of medical advice and health promotion campaigns.

Aged↗

PubMed1998

Developmental pattern of expression of NPDC-1 and its interaction with E2F-1 suggest a role in the control of proliferation and differentiation of neural cells.

We have previously identified NPDC-1, a gene specifically expressed in neural cells and involved in the control of cell proliferation and differentiation. In the present study, we have investigated the expression of this gene during mouse development and the interactions of the NPDC-1 protein with cell cycle regulatory proteins. The data show that NPDC-1 mRNA begins to be expressed in a variety of neural structures when the precursors enter into their terminal differentiation. They also indicate that in adult brain, the expression patterns of NPDC-1 and E2F-1 mRNA largely overlap. In addition, the NPDC-1 protein is able to interact directly with the transcription factor E2F-1 that participates in the regulation of the cell cycle, cell survival, and apoptosis. The present results suggest that NPDC-1 might be involved in the terminal differentiation and survival of neural cells and might act through interactions with E2F-1.

Animals↗

PubMed1998

Body weight preoccupation in middle-age and ageing women: a general population survey.

OBJECTIVE AND METHODS: The desired weights and dieting behavior of a sample of 1,053 women aged 30-74 years in the general population of Geneva, Switzerland, were explored by means of a questionnaire. Multivariate analyses of variance were performed. RESULTS: Twenty-five percent of the women were satisfied with their weight, whereas 71% wanted to be thinner, although 73% of them were at normal weight. Among women older than 65 years, 62% wanted to lose weight, 65% of them being at normal weight. For women wanting to lose weight, mean desired weight loss amounted to 9% of their current weight. Weight dissatisfaction increased with higher education (p < .001), and with increasing current weight (p < .001). Within the last 5 years, 42% of the women had dieted for weight control, including 67% at normal weight. Thirty-one percent of the women older than 65 years had also dieted, 62% of them being at normal weight. DISCUSSION: A majority of middle-age and ageing women in this general population sample expressed dissatisfaction about their weight. Many attempted dieting, even when they were at normal weight. Considering the vulnerability of the elderly to nutritional deficiencies, dieting to lose weight in normal weight ageing women should be discouraged or closely monitored.

Adult↗

PubMed1998

Proliferation and differentiation properties of permanent Schwann cell lines immortalized with a temperature-sensitive oncogene.

Permanent Schwann cells lines have been established in culture after stable transfection of newborn rat Schwann cells with the pJC-SVLTtsA vector, expressing a thermosensitive oncogene driven by the early promoter-enhancer region of the gliotropic GS/B variant of the papovavirus JC. The proliferation and differentiation of two clonal cell lines have been studied. The cells of these lines display the morphology of primary Schwann cells and express Schwann cell differentiation markers such as the S-100 protein, laminin, the low-affinity receptor to nerve growth factor and the glial fibrillary acidic protein. One of the lines is able to differentiate further. Indeed, in the presence of dorsal root ganglion neurones, the cells synthesize the myelin Po protein and are capable of some myelination, although to a lesser extent than secondary Schwann cells.

Animals↗

PubMed1997

Personalities and alimentary behaviors in obese patients.

The actual tendency in the care of obese patients is the association of dietetic information with an eating behavior therapy. Studies attempting to attribute the origin of obesity to psychiatric pathologies are contradictory. We studied whether certain eating disorders are more specific to a personality type. We studied eating disorders with the Eating Disorder Inventory (EDI) test in 281 obese women compared to 252 age-matched non-obese women. Both obese patients and non-obese volunteers were divided into four groups depending upon their personality (PERSONA test). This test defines four types of personality, based on the level of emotion (expansive or reserved) and the degree of power (dominant or consenting). According to our study, eating disorders vary between the four personality groups and were significantly higher in the facilitating group (consenting and expansive) compared to the three other obese groups. Neither promoting (expansive and dominant) nor controlling obese patients (dominant and reserved) present eating disorders. The analyzing obese patients (reserved and consenting) are reticent when it comes to consulting (18%) since they distrust others. Analyzing obese patients present an interpersonal distrust and an interoceptive awareness. The group which presents most eating disorders is that of facilitating obese patients (consenting and expansive). These present eating disorders of the compulsive types favored by interoceptive awareness, body dissatisfaction, ineffectiveness, and maturity fears. The diversity, even the absence, of eating disorders brought to evidence by our tests based upon different personality types should allow better understanding of the psychological and behavioral causes of weight gain and the means for improving compliance in the following of an obese patient.

Adult↗

PubMed1997

Purification, molecular cloning, and functional expression of the human nicodinamide-adenine dinucleotide phosphate-regulated thyroid hormone-binding protein.

The kidney and several other thyroid hormone-responsive tissues contain a NADP-regulated thyroid hormone (TH)-binding protein (THBP), with an apparent molecular mass of 36 kDa on SDS-PAGE, responsible for most of the intracellular high-affinity T3 and T4 binding. THBP was purified to homogeneity from human kidney cytosol and used to generate proteolytic peptides. Microsequencing of four peptides revealed identity to amino acid sequences deduced from a human cDNA homolog to a cDNA encoding kangaroo mu-crystallin. This protein is a major structural kangaroo lens protein with no known function in other species. A full-sized cDNA (TH5.9) was isolated by 5'- and 3'-rapid amplification of cDNA ends using a human brain cDNA library and gene-specific PCR primers, confirming identity to the previously cloned human cDNA. The TH5.9 cDNA encodes a 314-residue protein (theoretical mol wt = 33,775) with significant homologies (40 to 60%) with two bacterial enzymes: lysine cyclodeaminase and ornithine cyclodeaminase. The TH5.9 cDNA was expressed in Escherichia coli as a glutathione S-transferase (GST) fusion protein. Purified GST fusion protein, but not GST, bound T3 specifically with high affinity [dissociation constant (Kd) = 0.5 nM] in the presence of NADPH, and was labeled by UV-driven cross-linking of underivatized [(125)I]T3. T3 binding and photoaffinity labeling of GST fusion protein were activated by NADPH [activation constant (K[act]) = 10(-8) M], but not by NADH. The expressed protein displays the appropriate binding properties, indicating that TH5.9 cDNA encodes the NADP-regulated THBP characterized in human tissues.

Amino Acid Sequence↗

PubMed1997

[Identification of NPDC-1, gene involved in the control of proliferation and differentiation of neural and glial precursors].

Most of the genes involved in the regulation of proliferation and differentiation of neural cells remain to be identified. With the aim of identifying such genes, the strategy we used was to search for cDNAs which both hybridized with helix-loop-helix degenerated probes and corresponded to RNAs expressed preferentially when neural precursor cells become growth-arrested and began to differentiate. This led to the isolation of NPDC-1 cDNA and then of the genomic sequence. We observed that NPDC-1 is specially expressed in the nervous system and that the transfection of neural precursors with NPDC-1 cDNA results in the inhibition of cell proliferation. Moreover, the stable introduction of NPDC-1 into transformed cells downregulates cell proliferation both by increasing the generation time and by suppressing transformed and tumorigenic properties. We verified that these biological effects were reversed by NPDC-1 anti-sense oligonucleotides. Then we have examined the expression of NPDC-1 mRNA along mouse development and the interactions of the NPDC-1 protein with cell cycle regulatory proteins. The results showed that NPDC-1 mRNA begins to be expressed in a variety of neural structures, when the precursors enter their terminal differentiation. In addition, we have observed that NPDC-1 protein interacts with the transcription factor E2F-1. As a whole, the present results show that NPDC-1 down-regulates the proliferation of neural precursors, is able to suppress oncogenic transformation, is involved in the terminal differentiation of neural cells and acts probably through interactions with E2F-1.

Animals↗

PubMed1995

Identification of a neural-specific cDNA, NPDC-1, able to down-regulate cell proliferation and to suppress transformation.

Immortalized neural precursor cell lines carrying the polyoma large tumor (T) gene have been shown previously to retain a clear-cut contact inhibition of growth and to differentiate in vitro. In the present study, we have identified and isolated cDNA clones corresponding to RNA expressed preferentially when these cells reach confluence. One of them, NPDC-1, is expressed specifically in the nervous system. The transfection of dividing cells with a NPDC-1 expression vector results in the inhibition of cell proliferation. In addition, the stable introduction of NPDC-1 into transformed cells, even of nonneural origin, leads to the suppression of transformed characteristics.

Amino Acid Sequence↗

PubMed1995

A permanent glial precursor cell line, immortalized with the adenovirus E1A gene, undergoes apoptosis in restrictive growth conditions.

We have previously described some differentiation properties of the ERD.1.1 cell line, obtained after transfer and integration of the adenovirus-5 E1A gene. Depending on the growth conditions, these cells differentiate towards the astrocyte or early oligodendrocyte differentiation pathway. However, in growth restrictive conditions, we observed dying cells that detached from the monolayer constituted of differentiating cells. This led us to examine the characteristics of the dying cells. The study of the low-molecular-weight DNA and the ultrastructural examination of chromatin showed that these cells were undergoing apoptosis. The results also suggest that the expression of an integrated polyoma middle T gene can partly save the cells from apoptosis.

Adenovirus E1A Proteins↗

PubMed1994

Immortalization of different precursors of glial cells with a targeted and temperature-sensitive oncogene.

Different types of glial precursor cell lines were obtained after stable transfection of brain cells with the pJC-SVLTtsA vector carrying the tsA58 simian virus 40 large T (SVLT) gene driven by the promoter of a gliotropic strain of JC papovavirus. The immortalized cells were conditional for growth: they expressed the SVLT antigen and proliferated at 34 degrees C, but their growth was either reduced or arrested when they were shifted to 39 degrees C. The differentiation characteristics of four representative lines were more extensively studied. The CR15 and CM8 lines displayed properties of bipotential glial progenitors: they were able to express oligodendrocyte markers at both temperatures, but could differentiate into astrocytes only at 39 degrees C. In contrast, the CR19 and CM3r lines corresponded to more committed oligodendrocyte precursors: they expressed various oligodendroglial markers but they could not synthesize the glial fibrillary acidic protein. More particularly, the CM3r mouse cells displayed a typical oligodendrocyte progenitor morphology and expressed the proteolipid protein mRNA.

Animals↗

PubMed1994

[Dance training and eating disorders].

Medical history, eating habits, weight, current symptomatology and EDI (Eating Disorders Inventory)-scores of 41 bulimic female patients with and without past training in dancing, who came for treatment to an outpatient clinic, were compared. It was found that both groups of patients were not different for age, age at beginning of bulimia, actual as well as minimal and maximal BMI (Body mass index), length and severity of symptomatology, frequency of bulimic behaviors, and scores on the subscales of the EDI, but it should be noted that these similarities might be in relationship with some methodological shortcomings. Considering the prevalence of bulimia nervosa in women and the high frequency of ballet and sports training in teenagers, some hypotheses about the possible influence of strenuous physical exercise in childhood on the symptomatology and some psychological traits in adults with anorexia nervosa, bulimia nervosa, or binge-eating disorder are presented. Further studies, including standardized scales and larger samples, are necessary.

Adolescent↗

PubMed1993

Proliferation and differentiation properties of bipotent glial progenitor cell lines immortalized with the adenovirus E1A gene.

Bipotent glial progenitors have been immortalized by the transfer of the adenovirus E1A gene into primary cultured cells from embryonic rat brain. The lines obtained are phenotypically untransformed, retain growth contact-inhibition, and are able to differentiate, unless they are surtransfected with transforming oncogenes. Depending on the growth conditions, these immortalized cells express differentially either oligodendrocyte or astrocyte-specific markers and genes. After being seeded in serum-free medium, they display gangliosides recognized by A2B5 monoclonal antibody, and then they express sequentially O4 epitopes, galactocerebroside, and the myelin protein DM20. When grown in serum-supplemented medium, the cells express at first A2B5 epitopes, and then transiently O4 and galactocerebroside; after reaching confluence, O4 and galactocerebroside become undetectable, whereas the cells begin to coexpress glial fibrillary acidic protein and glutamine synthetase. These results indicate that the cell lines can undergo a differentiation reminiscent both of O-2A progenitors and of plastic process-bearing glial subpopulations. The cells were also genetically marked by the stable introduction of the nlslacZ reporter gene. Thus, the lines could be useful for studying direct interactions in vitro, or for post-grafting investigations. They should also provide a model for studying the mechanisms involved in the commitment and in the control of proliferation and differentiation of this cell lineage. This suggestion is consistent with the data indicating a growth arrest-dependent differential expression of a novel gene encoding a protein with a helix-loop-helix domain.

Adenovirus E1A Proteins↗

PubMed1993

Grafting of fast blue labeled glial cells into neonatal rat brain: differential survival and migration among cell types.

Cultures of oligodendrocyte progenitor cells, ERD 1.1 cells, a nontransformed immortalized cell line of oligodendrocyte progenitors and C6 glioma cells were labeled with the fluorescent dye Fast Blue and transplanted into brains of 4 day postnatal Wistar rat pups. The localization of fluorescent cells within host brain was examined at various times post-transplantation to determine patterns of cell migration as well as survival and integration among the host tissue. Oligodendrocyte progenitors migrated mainly along white matter tracks, integrating successfully into the host parenchyma. High survival rates were found between 5 and 27 days post grafting. ERD 1.1 cells survived and migrated between 1 and 5 days after transplantation. However, by 27 days survival had dropped from 60 to 20% of the initial cell population. The surviving cells were mainly localized to subventricular and subependymal regions at 27 days. C6 cells migrated extensively rostrally and caudally from the site of injection in the hippocampus and were tumorogenic. This finding confirmed previous reports on the survival and migration patterns of oligodendrocyte progenitors grafted into neonatal brain. However, they show that two cell lines that share phenotypic properties of oligodendrocyte progenitors markedly differ from these cells with respect to migration patterns and integration within host parenchyma. Fast Blue dye was still detectable after repeated cell division in grafted C6 cells, enabling us to track single cells as well as tumor formation. This dye should be useful not only to address issues of development, but also of tumor biology and therapeutic treatment.

Amidines↗

PubMed1992

Effects of TGF beta 1 on the proliferation and differentiation of an immortalized astrocyte cell line: relationship with extracellular matrix.

The astrocyte cell line (C.LT.T.1.1.), which is immortalized and has retained a normal density-dependent regulation of growth, is a suitable model for studying the relationships between proliferation, differentiation, and the production of extracellular matrix. The growth factor TGF beta 1 was used to modulate these processes. When added to proliferative cells, it inhibited growth and caused morphological changes. It also suppressed the growth arrest at confluence, so that the cells formed multilayers of parallel spindle-shaped cells. Whereas untreated control cells expressed progressively the glial fibrillary acidic protein (GFAP) after arrest of multiplication, the addition of TGF beta 1 to proliferative cells prevented GFAP expression and accumulation of its mRNA. Concomitantly, it increased the amounts of laminin, fibronectin, and collagens synthesized during the growth phase and greatly altered the composition and the structure of the matrix deposited at confluence. In contrast, when added after cell differentiation had begun, TGF beta 1 did not alter the appearance of the matrix whereas it still stimulated, but to a lesser extent, extracellular matrix components production. The results show that TGF beta 1 prevents the transition from the proliferating to the differentiating state and correlatively alters the composition and structure of the extracellular matrix.

Animals↗