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C Gautier

Publications and source records attributed to C Gautier.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Dermatitis caused by estrogens].

BACKGROUND: We report a case of sensitization to estrogen. CASE REPORT: A 40-year-old woman consulted for skin disorders which followed a cyclic pattern. At each menses, the patient developed pruritus and erythematous papulovesicular lesions over the members and trunk. Estraderm patch contact dermatitis was evident. Prick and patch tests with alcoholic solutions of estrone alone were positive. Serum tests were positive for anti-ethinyl-estradiol antibodies and anti-progesterone antibodies. DISCUSSION: Autoimmune dermatitis can be caused by sensitization to endogenous or exogenous sex hormones. Clinical manifestations and histological findings are variable and non-specific. The cyclic nature of the manifestations is however quite suggestive. Positive prick and patch tests performed with alcohol solutions of the hormones may give the diagnosis and serum tests may be positive for specific anti-steroid antibodies. These complementary explorations are however difficult to perform and interpret and definitive diagnosis is based on an association of clinical findings, skin tests, laboratory tests and the clinical course. In case of progesterone sensitization, the treatment of choice is estrogen inhibition of ovulation. For estrogen sensitization, anti-estrogen treatment appears to be more effective. Finally, bilateral ovariectomy may be required in difficult cases.

Administration, Cutaneous↗
PubMed1997

Impact of changes in GC content on the silent molecular clock in murids.

Murid nuclear genomes are more homogeneous in GC content than those of most mammals, which leads to the question of how such important compositional changes have accumulated. This paper reports on relationships between frequencies of synonymous differences and GC change, in the lineages leading to human and murids. For this, we used the four-species approach: GC changes between human and murids were compared to the frequencies of synonymous differences, measured between two independent species without GC change (bovine and pig), by using orthologous genes common to all four species. We report three conclusions: (1) Among genes with little GC change, 60% of the variability of synonymous substitution frequencies is explained by the gene-specific rate component. (2) GC changes in murid genomes are independent of the gene-specific rate component. Slowly evolving genes in pig bovine comparison can show strong GC change in murids. (3) By using a GC-independent estimate of the substitution rate, we show that GC changes in murid genomes increase synonymous substitution frequencies. The GC homogenization considerably weakens the gene-specific conservation of substitution rates in murids, and could explain part of the increase of evolutionary rates observed in this group. We present a mechanism that can account for the evolution of the GC homogenization in murids.

Animals↗
PubMed1997

Expression and regulation of transforming growth factor beta1 mRNA and protein in rat fetal testis in vitro.

The expression and secretion of Transforming Growth Factor beta1 (TGFbeta1) by cultured testes of day 20.5 rat fetuses were investigated. The testes were found to express two TGFbeta1 mRNA transcripts of 2.5 and 1.8 kb. By using mink lung epithelial cell bioassay based on the measurement of the inhibition of tritiated thymidine incorporation in response to TGFbeta1 immunoreactive material, the fetal testes were shown to secrete TGFbeta1 protein in organ culture. This secretion was positively regulated by dibutyryl cyclic AMP or by LH and FSH together, but not by LH alone and very slightly by FSH alone, which suggests interactions between Leydig and Sertoli cells for the control of TGFbeta1 production. These regulations probably take place at a posttranscriptional step since no concomitant increase of TGFbeta1 mRNA levels was observed. Such a positive regulation of TGFbeta1 secretion by gonadotropins could be a characteristic of the rat fetal testis.

Animals↗
PubMed1997

Transforming growth factor beta1 inhibits steroidogenesis in dispersed fetal testicular cells in culture.

TGF beta1 has been detected by immunohistochemistry in the rat fetal testis. Therefore, we attempted to determine whether this factor can act as a local regulator of Leydig cell function during fetal development. An inhibitory effect of TGF beta1 on basal and luteinizing hormone (LH)-stimulated testosterone secretion by fetal testes in vitro was observed only with testes from 13.5 day-old fetuses and not with testes from older stages. The lack of effect of exogenous TGF beta1 in organ culture after day 13.5 might be related to an elevated intratesticular concentration that would already exert maximal biological effect. On the contrary, in a model of dispersed testicular cells in culture, TGF beta1 was able to inhibit LH-stimulated testosterone production by fetal Leydig cells from 16.5 and 20.5 day-old fetuses. This inhibition of LH-stimulated testosterone production was dose- and time-dependent and was maximal after 48 h of treatment with 1 ng/ml TGF beta1, with testosterone secretion being reduced to 25% of control values. Inhibition of testosterone secretion was also observed in basal and dbcAMP-stimulated conditions, suggesting that one site of action of TGF beta1 is located after the production of cAMP. However, TGF beta1 was also able to inhibit LH-induced cAMP production. As demonstrated by the transformation of steroidogenic precursors into testosterone, TGF beta1 did not significantly alter 3beta-hydroxysteroid dehydrogenase (3beta HSD) activity but induced a strong inhibition of cytochrome P450 17alpha-hydroxylase/C17-20 lyase (P450C17) activity which was associated with a marked diminution of cytochrome P450C17 mRNA levels (26% of control values) but not of cytochrome P450scc mRNA. In addition to its effect on steroidogenesis, TGF beta1 exhibited morphogenic actions on the fetal testicular cells, inducing spreading when the cells were adherent and aggregation when the cells were cultured in conditions of lesser adherence and without any significant effect on either total cell number or 3beta HSD positive cells. Taken together these results suggest that TGF beta1 likely plays a morphogenic and physiological role very early in the fetal testis via paracrine/autocrine mechanisms.

Animals↗
PubMed1997

The immunohistochemical localization of transforming growth factor-beta 2 in the fetal and neonatal rat testis.

The localization of transforming growth factor beta-2 (TGF beta 2) in the fetal and neonatal testis (from day 13.5 of fetal life to postnatal day 9) was investigated by an immunohistochemical staining method employing a specific polyclonal antibody. Immunostaining appeared on fetal day 13.5 in primitive Sertoli cells as they begin to come in contact with each other and surround the germ cells to form the seminiferous cords. Staining in Sertoli cells was still clearly observed until fetal day 16.5 and became faint or undetectable from fetal day 18.5 onwards. In fetal-type Leydig cells, a positive reaction for TGF beta 2 appeared on day 16.5 and became very intense from day 18.5 onwards. In the germ cells, immunoreactivity for TGF beta 2 appeared on fetal day 20.5, rose to a maximum on postnatal day 4 and decreased thereafter. On postnatal day 9, staining was still present in type A spermatogonia and absent in type B spermatogonia. No immunoreactivity was detected in peritubular cells on any day studied. In conclusion, our results are in favour of an autocrine/paracrine role of TGF beta 2 in the differentiation of the testis during the perinatal period. It may be involved in the organization of the seminiferous cords, the regulation of testosterone production and the regulation of the number of germ cells. When compared with the immunolocalization of TGF beta 1 that we have previously reported [1], the present study suggests that the roles of TGF beta 2 in the developing rat testis can be specific but also overlap from those of TGF beta 1.

Animals↗
PubMed1997

Evolution of isochores in rodents.

The most deviant isochore pattern within mammals was found in rat and mouse; most other mammals possess a different kind of isochore organization called the "general pattern." However, isochore patterns remain largely unknown in rodents other than mouse and rat. To investigate the taxonomic distribution of isochore patterns in rodents, we sequenced the nuclear gene LCAT (lecithin:cholesterol acyltransferase) from 17 rodents species (bringing the total of LCAT sequences in rodent to 19) and compared their GC contents at third codon positions and in introns. We also analyzed an extensive sequence database from rodents other than rat and mouse. All murid LCAT sequences are much poorer in GC than all nonrodent LCAT sequences, and the hamster sequence database shows exactly the same isochore pattern as rat and mouse. Thus, all murids share the same special isochore pattern--GC homogenization. LCAT sequences are GC-poor in hystricomorphs too, but the guinea pig sequence database indicates that large changes in GC content occur without an overall modification of the isochore pattern. This novel mode of isochore evolution is called GC reordering. LCAT sequences also show that the evolution of isochores in sciurids and glirids is nonconservative in comparison with that in nonrodents. Thus, at least two novel patterns of isochore evolution were found. No rodent investigated to date shared the general mammalian pattern.

Animals↗
PubMed1997

[Estimation of the treatment cost of cervical cancer].

BACKGROUND: The goal of this study was to estimate direct costs induced by the first year of treatment of cervix cancers according to the stage at diagnosis. METHODS: Fifteen patients of the Gynaecology Department of the Besançon hospital (Doubs, France) were involved in a prospective study to estimate the real cost of treatment of carcinomas in situ (CIS) by conization and of microinvasive carcinomas (MIC) by simple hysterectomy. Costs of invasive cancers were obtained from a retrospective analysis of 24 hospital records in the Radiotherapy Department. RESULTS: The average real cost of treatment for the CIS was 5023 FF (1995 French Francs). Real treatment cost of the MIC was 15,867 FF. The average cost of treatment for the IB and IIA cancers stage (FIGO classification) was 61,540 FF and 145,314 FF for the IIB to IV stage cancers. CONCLUSIONS: Cost-estimation of cervix cancer treatment according to the stage of diagnosis has to be done before starting a cost-effectiveness analysis of mass screening for cervix cancers. This study will allow us to take into account changes in the stages distribution following on a screening campaign.

Carcinoma in Situ↗
PubMed1997

[Isolated mucosal ulcers disclosing idiopathic hypereosinophilic syndrome].

INTRODUCTION: Idiopathic hypereosinophilic syndrome is an uncommon disease often associated with diverse non-specific skin manifestations. Mucosal ulcerations suggest a myeloproliferative from with poor prognosis due to possible progression to malignant hemopathy or visceral complications. CASE REPORT: A 28-year-old man presented idiopathic hypereosinophilia with isolated mucosal ulcerations involving the buccal and genital areas. Laboratory results (hematology, CD25) suggested a myeloproliferative form. Treatment with alpha interferon (18 months) led to regression of the mucosal lesions and a decrease in the markers of eosinophil toxicity. There was no visceral involvement. DISCUSSION: Immunosuppression with/without high-dose alpha interferon is usually used for the treatment of hypereosinophilic syndrome. In our case favorable outcome was obtained with lower doses of alpha interferon than those reported in the literature. There was objective decrease in eosinophil toxicity (regular counts of hypodense eosinophils, CD25 or interleukin 2 soluble receptor) and no progression (malignant hemopathy, mortal visceral involvement).

Adult↗
PubMed1997

[Melanoma of soft tissues].

INTRODUCTION: Soft tissue melanoma was described in 1965 by Enzinger who used the term clear-cell sarcoma. In 1983, Chung and Enzinger coined the term soft tissue melanoma due to the immunohistochemical similarity with melanoma. We report a case of this rare type of melanoma. CASE REPORT: A 59-year-old woman had pain between the first two toes for 3 years. A subcutaneous tumor was found at examination. Histologically, the tumor was composed of weakly eosinophilic cell proliferation. Protein S100 and HMB45 were positive. The cells were organized in theques. Pathology diagnosis was soft tissue melanoma. Complete remission was obtained for 3 years when several local recurrences required surgery and chemotherapy then surgery and radiotherapy. Complete remission has been achieved for 9 months. DISCUSSION: This case presented the main characteristics of soft tissue melanoma as described in a review of 209 analyzable cases reported in the literature. This tumor occurs in young subjects with no sex or race predominance. It is an ubiquitous tumor which develops in close relation with tendons and aponevroses, usually in limbs (especially feet). Pain is sometimes the revealing manifestation, but the tumor is often asymptomatic, so the volume is often important at diagnosis. Pathology examination shows rather monomorphic proliferation of cells with a clear or weakly eosinophilic cytoplasm grouped in clusters or theques separated by fibrous septa. Intracytoplasmic melanin is sometimes observed, indicating interest of protein S100 and HMB45 immunohistochemistry which is almost always positive. The principle differential diagnoses are metastasic melanoma and epithelioid sarcoma. Prognosis of soft tissue melanoma is similar to that in sarcomas with a high rate of local recurrence and metastases (lymph nodes, lungs). Mortality reaches 56 p. 100. Treatment is wide surgical exeresis. CONCLUSION: Soft tissue melanoma is a rare tumor of the melanocyte. It differs from melanoma by the population involved, its clinical expression and its prognosis which is similar to that in sarcoma.

Combined Modality Therapy↗
PubMed1996

Immunohistochemical localization of transforming growth factor beta 1 and beta 2 in the fetal and neonatal rat ovary.

The localization of transforming growth factor beta (TGF beta) in the differentiating ovary (from fetal day 13.5 to postnatal day 14) was investigated immunohistochemically using polyclonal antibodies for TGF beta 1 and TGF beta 2. Immunostaining was undetectable in the gonadal primordium on fetal day 13.5. From fetal day 14.5 and throughout fetal life, there was intense immunostaining for TGF beta 1 and faint staining for TGF beta 2 in some ovarian somatic cells which were identified as epithelial cells at the end of fetal life. This pattern of staining was also found in the presumptive granulosa cells present between the oocytes on postnatal day 1. The staining for TGF beta 2 persisted while the staining for TGF beta 1 decreased in the granulosa cells of primordial and primary follicles of older rats. In the subsequent stages of follicular development, the staining for TGF beta 1 disappeared while faint staining for TGF beta 2 persisted in the granulosa cells of secondary and small antral (postnatal day 14) follicles. On day 14, the newly functional thecal/interstitial cells were moderately stained for TGF beta 2 and intensely stained for TGF beta 1. These results plus our previous immunolocalization of TGF beta 1 in the fetal testis [13] show that, in both sexes: (1) TGF beta 1 is detectable in the gonads on the same fetal age (day 14.5); (2) TGF beta 1 is present in the somatic cells which are the precursors of Sertoli and granulosa cells, at the time of their organization in seminiferous tubules or in primordial follicles; and (3) TGF beta 1 is largely present in cells synthesizing androgens, from the onset of their steroidogenic capacity (fetal day 16.5 for Leydig cells and postnatal day 14 for thecal/interstitial cells.

Animals↗
PubMed1996

SEAVIEW and PHYLO_WIN: two graphic tools for sequence alignment and molecular phylogeny.

SEAVIEW and PHYLO_WIN are two graphic tools for X Windows-Unix computers dedicated to sequence alignment and molecular phylogenetics. SEAVIEW is a sequence alignment editor allowing manual or automatic alignment through an interface with CLUSTALW program. Alignment of large sequences with extensive length differences is made easier by a dot-plot-based routine. The PHYLO_WIN program allows phylogenetic tree building according to most usual methods (neighbor joining with numerous distance estimates, maximum parsimony, maximum likelihood), and a bootstrap analysis with any of them. Reconstructed trees can be drawn, edited, printed, stored, evaluated according to numerous criteria. Taxonomic species groups and sets of conserved regions can be defined by mouse and stored into sequence files, thus avoiding multiple data files. Both tools are entirely mouse driven. On-line help makes them easy to use. They are freely available by anonymous ftp at biom3.univ-lyon1.fr/pub/ mol_phylogeny or http:@acnuc.univ-lyon1.fr/, or by e-mail to galtier@biomserv.univ-lyon1.fr.

Animals↗
PubMed1996

[Post-radiotherapy cutaneous neuro-endocrine carcinoma].

INTRODUCTION: Merkel cell carcinoma or cutaneous neuroendocrine carcinoma is an uncommon severe disease. The carcinogenic effect of ionizing radiations has been suspected in exceptional observations. We report the sixth case of Merkel cell neuroendocrine carcinoma in a patient with prior radiotherapy. CASE REPORT: An 86-year-old man underwent radiotherapy for a basal cell carcinoma of the tip of the nose and developed a highly aggressive Merkel cell carcinoma at the same location 6 years later. DISCUSSION: The development of Merkel cell carcinoma on irradiated tissue accounts for 2.6 p. 100 of the 227 publications where dermatological history was reported. This percentage may be underestimated. The similar localizations of the irradiated zone and the site of cancer development 5 years later suggest that the Merkell cell carcinoma may be a radio-induced tumor. The delay may vary from 5 to 47 years. The similarity of the carcinogenic factors involved in Merkel cell carcinoma and squamous cell or basal cell carcinomas (ultraviolet, ionizing irradiation) and the frequent association of different types favor an epidermal origin for Merkel cell carcinoma. In clinical practice, past history of radiotherapy in an area where Merkell cell carcinoma develops indicates that therapeutic management must exclude post-operative radiotherapy.

Aged↗
PubMed1995

Breast cancer in elderly women: a retrospective analysis of combined treatment with tamoxifen and once-weekly irradiation.

PURPOSE: To evaluate retrospectively the efficacy of combined modality treatment (hormone therapy and hypofractionated radiotherapy) in a population of very elderly women with breast cancer. METHODS AND MATERIALS: Records on 70 patients of median age 81 years, treated between January 1988 and February 1994, whose median follow-up is now 36 months, have been evaluated. Information obtained included clinical stage at diagnosis, histology, tumor grading, hormone receptor levels, details of treatment, type of failure, survival data, and status at last follow-up examination. Treatment consisted of Tamoxifen 20 mg daily and a hypofractionated course of high dose-per-fraction once-weekly radiotherapy. In the majority of cases this consisted of seven exposures of 6.5 Gy (five to the involved breast, and two to the tumor bed) given over 6 weeks, on a 60Co unit. Nodes were treated when clinically involved, to a dose of 27.5-30 Gy in five to six fractions. RESULTS: At median follow-up of 36 months, the overall survival rate is 87% [confidence interval (CI) 78-95%], the disease specific survival rate is 88% (CI 80-96%), and 72% (CI 60-84%) of patients are free of disease. The local control rate at 36 months is 86% (CI 76-95%). When analyzed by T stage, 81% of T1 patients, 96% of T2 patients, 60% of T3 patients and, paradoxically 100% of T4 patients were in local control at 36 months, although at that point there were just four such patients available for consideration in the T4 group. Initial response to hormone therapy does not appear to be a predictive indicator for ultimate loco-regional control. There is a trend towards greater probability of loco-regional failure if total dose delivered to the breast is less than 35 Gy. CONCLUSIONS: Women of elderly age are often denied combined modality therapy, because of coexistant disease or fears held by the responsible physicians that elderly patients are unable to tolerate surgery or protracted courses of radiotherapy. Consequently, many are treated by tamoxifen alone with poor results. This study demonstrates that very high rates of loco-regional control are achievable using hormonal treatment combined with high dose-per-fraction once-weekly radiotherapy.

Aged↗
PubMed1995

Regulation of argininosuccinate synthetase level by corticosteroid and pancreatic hormones during perinatal period.

The urea cycle takes place in the hepatocyte of ureothelic animals. The conversion of ammonia into urea involves five reactions. The first 2 take place in the matrix of the mitochondria, the last 2 occur in the cytosol. Argininosuccinate synthetase (AS) is the third reaction of the urea cycle. It catalyses the condensation of citrulline and aspartate into argininosuccinate. We have previously reported that rat AS activity was present in the cytosol and the outer membrane of the mitochondria. We have shown that, at the activity level, the colocation of AS was changing during fetal and neonatal development and was under the control of corticosteroid and pancreatic hormones. However, an unresolved issue was whether both AS had the same specific activity and that their location was changing during ontogenesis or that the specific activities of mitochondrial and cytosolic enzymes were different and/or modified during this period. In the present report, we compared the compartmentalization of AS activity and protein level in the fetus, the new-born and the adult rat and the role of corticosteroid and pancreatic hormones. Specific activities of both AS remained unchanged during ontogenesis. Glucocorticoids induced an increase in mitochondrial AS while glucagon appeared to induce a concomitant decrease in the level of mitochondrial AS and an increase in cytosolic AS.

Adrenal Cortex Hormones↗
PubMed1995

SARs, ARSs, and A,T-rich regions evidenced by restriction mapping on an 835-kb DNA fragment from Drosophila.

In Drosophila, sequences anchoring the DNA molecule to the scaffold (SARs) and sequences able to replicate autonomously (ARSs) had been shown to comap on an 835-kb DNA fragment (Brun et al. (1990) Mol. Cell. Biol. 10, 5455-5463). To investigate the question of whether this comapping results from the coincidental recruitment of SARs and ARSs in A,T-rich regions, A,T-rich regions of the 835-kb DNA fragment have been identified by restriction analysis with enzymes recognizing motifs made exclusively of A and T. Within the limits of sensitivity of this approach, the obtained data favor the idea of a noncoincidental recruitment: obviously a SAR and an ARS subpopulation are preferentially localized in the A,T-rich regions, but not every A,T-rich region displays a SAR activity, or an ARS activity, or both, nor are all SARs or ARSs localized in the A,T-rich regions. In addition, the data support the idea that a statistical assessment of base composition using restriction analysis might be developed into a general useful approach to genome organization.

Adenine↗
PubMed1995

Statistical analysis of vertebrate sequences reveals that long genes are scarce in GC-rich isochores.

We compared the exon/intron organization of vertebrate genes belonging to different isochore classes, as predicted by their GC content at third codon position. Two main features have emerged from the analysis of sequences published in GenBank: (1) genes coding for long proteins (i.e., > or = 500 aa) are almost two times more frequent in GC-poor than in GC-rich isochores; (2) intervening sequences (= sum of introns) are on average three times longer in GC-poor than in GC-rich isochores. These patterns are observed among human, mouse, rat, cow, and even chicken genes and are therefore likely to be common to all warm-blooded vertebrates. Analysis of Xenopus sequences suggests that the same patterns exist in cold-blooded vertebrates. It could be argued that such results do not reflect the reality because sequence databases are not representative of entire genomes. However, analysis of biases in GenBank revealed that the observed discrepancies between GC-rich and GC-poor isochores are not artifactual, and are probably largely underestimated. We investigated the distribution of microsatellites and interspersed repeats in introns of human and mouse genes from different isochores. This analysis confirmed previous studies showing that L1 repeats are almost absent from GC-rich isochores. Microsatellites and SINES (Alu, B1, B2) are found at roughly equal frequencies in introns from all isochore classes. Globally, the presence of repeated sequences does not account for the increased intron length in GC-poor isochores. The relationships between gene structure and global genome organization and evolution are discussed.

Animals↗
PubMed1995

Frequencies of synonymous substitutions in mammals are gene-specific and correlated with frequencies of nonsynonymous substitutions.

The frequencies of synonymous substitutions of mammalian genes cover a much wider range than previously thought. We report here that the different frequencies found in homologous genes from a given mammalian pair are correlated with those in the same homologous genes from a different mammalian pair. This indicates that the frequencies of synonymous substitutions are gene-specific (as are the frequencies of nonsynonymous substitutions), or, in other words, that "fast" and "slow" genes in one mammal are fast and slow, respectively, in any other one. Moreover, the frequencies of synonymous substitutions are correlated with the frequencies of nonsynonymous substitution in the same genes.

Animals↗