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Y Gauthier

Publications and source records attributed to Y Gauthier.

At least 37 records · Page 2Linked to original sources
PubMed1992

Autologous grafting with noncultured melanocytes: a simplified method for treatment of depigmented lesions.

BACKGROUND: Achromic lesions on the trunk and the extremities often do not respond to treatment and little improvement is obtained in cases of segmental vitiligo. OBJECTIVE: Transplantation of autologous noncultured melanocytes was performed to obtain a successful repigmentation. METHODS: The grafting method is carried out in two steps: production of blisters on the depigmented lesions by freezing with liquid nitrogen and injection in each blister of a suspension of epidermal cells (mainly keratinocytes and melanocytes). The cellular suspension was obtained from samples of skin of the hair scalp after trypsinization. RESULTS: Repigmentation was evident within 25 to 30 days. Coalescence of the pigmented areas was spontaneously observed or obtained after UVA stimulation. Patients with two types of leukoderma-vitiligo or nevus depigmentosus had successful repigmentation after transplantation of autologous noncultured melanocytes. CONCLUSION: This technique appears to be an effective and simple method for treating patients with achromic areas lacking melanocytes.

Adult↗
PubMed1992

Child and adult psychiatry: comparison and contrast.

Since its development from general psychiatry, child psychiatry has been influenced by its close involvements with the child guidance movement and pediatrics and by the age of its patient population. This has led it to evolve in ways quite distinct from adult psychiatry, so much so that at times the understanding and relationship between the two disciplines has been somewhat strained. This paper relates the development of child psychiatry to its history, its tasks and its patient population, highlighting some of the major differences between child and adult psychiatry. It then looks at why research in child psychiatry has lagged behind research in adult psychiatry. It concludes by discussing tensions between the two disciplines, and why it serves the interests of both professions as well as those of our patients, that a better understanding and collaboration between them be established.

Age Factors↗
PubMed1992

[Use of a disposable peroperative autotransfusion device in uncomplicated vascular surgery].

We used a simple single process to recover total blood during surgery. All the process stands on a low burdensome jib and does not require additional staff in theater. Its cost is low. The indications concern all surgical operations enduring low or mean bleeding, except in septic and cancer surgery. It may be used in emergencies, even in war surgery with an incorporated source of depression.

Animals↗
PubMed1992

[Progressive and confluent hypomelanosis of the melanodermic metis].

Melanodermic half-castes may develop a progressive and extensive hypomelanosis presenting as an original skin condition. The course of the disease is characteristic: it occurs mainly in females from 18 to 25 years of age with a progressive development of hypochromic and coalescent macules on the back and abdomen. This disease may regress spontaneously within 5 years and healing seems to be facilitated by UV exposure. Decreased epidermal melanin is the only histological feature. Ultrastructural examination has led to characterize this bizarre disease by a switch from stage IV single melanosomes negroid type to small type I-III aggregated melanosomes (caucasoid phenotype of melanogenesis). Although the pathogenesis of the disorder remains obscure, it may be stated that the variation in skin coloration in these patients is due to a variation in melanosome size and distribution. It is possible that this variation is due to a decrease in production of type IV melanosomes and that this apparent change of ultrastructural phenotype represent the consequence of a simple imbalance in melanosomes production favoring small I to III melanosomes. This disease is not restricted to a limited geographic group: it is present in melanodermic half-castes of different areas and therefore deserves to be known and recognized.

Adult↗
PubMed1991

[Developmental psychopathology and psychoanalysis].

In face of the apparent contradiction between psychoanalysis and observational-experimental methods, the author briefly summarizes the input of direct observation to the knowledge of child development and suggests that the reservations of many psychoanalysts to these methods may be explained by the greater importance given to external events in such research, as if the causal role of fantasy was thus being questioned. The author further reviews most recent experimental works, particularly those around the concepts of "competence of the infant", "self", "attachment and security", and suggests that the main object of these research endeavors more and more concerns the foundations and origins of the child's fantasy life. Other recent experimental works bring out the continuity between the observations made during the first year of the child's life and those made of these children now up to the age of six. The author comes to the conclusion that the whole of these observational and experimental works, far from contradicting psychoanalytic hypotheses based on reconstruction, confirms institutions and hypotheses which have become essential to psychoanalysis, particularly concerning the importance of the child's first year of life and of mother-child interaction.

Child↗
PubMed1989

Developmental regulation of murine mammary-gland 90 kDa heat-shock proteins.

We have examined the regulation of murine mammary-gland 90 kDa heat-shock protein (hsp-90) as a function of normal development and differentiation. We find that both hsp-90 and amounts of its mRNA are modulated during development and differentiation, with the highest concentrations of mRNA and protein being present in tissues from pregnant and lactating animals respectively. Metabolic labelling experiments with [35S]methionine reveal that the rate of synthesis of hsp-90 also varies among tissues from various developmental states and correlates with the relative hsp-90 mRNA content. These data also suggest that the highest concentration of hsp-90 found in lactating mammary tissues may be due to a greater stability of this protein in this developmental state. The possible significance of the developmental modulation of mammary hsp-90 to mammary steroid-receptor properties is discussed.

Animals↗
PubMed1989

Transferrin receptor and ferritin levels during murine mammary gland development.

Various types of proliferating cell are known to express transferrin receptors which are necessary for transferrin-mediated cellular iron uptake. Neither the mechanism nor the physiological role of transferrin receptor induction has been established with certainty; although it may reflect an increased cellular requirement for iron which is essential for ribonucleotide reductase, a key enzyme of DNA synthesis. The aim of this study was to examine murine mammary gland transferrin-receptor levels during gland development. As compared to virgin controls, total mammary gland transferrin receptors expressed on the basis of DNA, increase during pregnancy and lactation by 29- and 45-fold, respectively. However, on the basis of DNA, mammary gland ferritin, measured by radioimmunoassay, decreased by about 75% and 85% during pregnancy and lactation, respectively, indicating that the increased transferrin receptor levels probably do not lead to intracellular iron accumulation. When epithelial cells from mammary glands of pregnant mice were cultured in vitro transferrin receptor expression correlated with cell proliferation. These results suggest that normal mammary growth which occurs mainly in mammary epithelial cells is associated with a significant increase in transferrin receptor. Since transferrin receptor levels remain high during lactation they are not associated solely with tissue growth, but may also function in transporting iron during milk production.

Animals↗
PubMed1989

Estrogenic regulation of murine uterine 90-kilodalton heat shock protein gene expression.

Murine uterine steady-state protein levels of the 90-kilodalton heat shock protein (HSP90) have been demonstrated recently to be increased by estrogen in a target tissue- and steroid-specific manner (C. Ramachandran, M.G. Catelli, W. Schneider, and G. Shyamala, Endocrinology 123:956-961, 1988). We now report that this regulation occurred with both the HSP86 and HSP84 forms of HSP90 as well as with the 94-kilodalton glucose-regulated protein. At the mRNA level, this response was greatest for HSP86 (15-fold). In contrast, estradiol had no significant effect on HSP70.

Animals↗
PubMed1988

Effects of progesterone, promegestone and RU 486 on glucocorticoid receptor levels in primary cultures of mouse mammary epithelial cells.

Mammary epithelial cells isolated from midpregnant mice and cultured on collagen gels contain glucocorticoid receptors whose levels are modulated by a variety of steroids. In the absence of any added steroid to the cell culture medium, the levels of glucocorticoid receptors in the cells decline during culture, which is counteracted by the addition of a variety of glucocorticoid agonists. The effectiveness of the glucocorticoid in preventing the loss of glucocorticoid receptors is in turn counteracted by the addition of the synthetic progestin promegestone and the synthetic antiglucocorticoid RU 486. Of the two, RU 486 is the most potent in antagonizing the effect of cortisol on the GR levels. Promegestone antagonizes the effect of cortisol, too, although higher concentrations are necessary. Progesterone was without a clear effect either as a glucocorticoid agonist or an antagonist. Progesterone, however, was extensively metabolized by mammary epithelial cells in culture. Based on these observations we conclude that in mammary epithelial cells glucocorticoids positively regulate the metabolism of their own receptors and that antiglucocorticoids, such as RU 486 and progestins, can antagonize that effect.

Animals↗
PubMed1988

Progressive macular hypomelanosis of the trunk: primary acquired hypopigmentation.

Dermatological practice in Martinique frequently encounters a bizarre skin condition presenting as a progressive and extensive hypomelanosis on the back. The course of this disorder is highly characteristic: it occurs mainly in females from 18-25 years of age, with a progressive development of round, pale, coalescent macules on the back and sometimes on the abdomen. This disease, which does not respond to therapy, spontaneously regresses within 3 to 4 years. Decreased epidermal melanin is the only histological feature. Ultrastructural examination of two cases found that the macular lesions were characterized by a switch from Stage IV single melanosomes (negroid) to small Type I-III aggregated melanosomes (caucasoid). It may thus be stated that the variation in skin coloration in these patients was due to a variation in melanosome size and distribution.

Adolescent↗
PubMed1988

[Quantitative approach of melanin in human cultured melanocytes].

The purpose of the study was to establish an in vitro model for the quantification of the melanin produced in human melanocytes in culture. Melanin content in these cultured human melanocytes is determined by spectrofluorimetric assay. Fluorescence intensity is quantitatively related to the melanin content present in cultured melanocytes.

Cell Count↗