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F Mouriaux

Publications and source records attributed to F Mouriaux.

12 recordsLinked to original sources
PubMed2001

Implication of stem cell factor in the proliferation of choroidal melanocytes.

The tyrosine kinase receptor c-kit and its ligand stem cell factor exert a broad range of biological activities during organogenesis. It also improves normal cell development including complex biological responses involved in the differentiation and proliferation of the melanocytes. Diffuse uveal melanocytic proliferation is a rare paraneoplasic syndrome, resulting in rapid bilateral visual loss due to proliferation of melanocytes within the choroid. We have therefore investigated whether the c-kit/stem cell factor pathway regulates the proliferation of choroidal melanocytes and also if such pathway plays a role in bilateral uveal melanocytic proliferation. Normal cultured melanocytes of the choroid and paraffin-embedded sections of melanocytic proliferation were studied. C-kit expression and effects of stem cell factor were measured. Western blot assays of cell extracts demonstrated that c-kit was expressed in choroidal melanocytes. Immunocytochemical analysis on cultured melanocytes showed a cytoplasmic distribution. Immunohistochemical analysis on melanocytic proliferation showed a strong cytoplasmic distribution in the pigmented spindle-shaped melanocytes localized in the multiple focal areas of choroidal thickening. The addition of stem cell factor did not change melanocyte morphologies and was mitogenic in the presence of bFGF, isobutyl-1-methylxanthine and cholera toxin. In contrast, stem cell factor was not able to produce any significant melanin. Activation of c-kit by its ligand may contribute to the proliferation of choroidal melanocytes.

Adult↗
PubMed2001

[Orbital exenteration].

Exenteration of the orbit is a disfiguring and destructive procedure that is usually reserved for treatment of life-threatening orbital malignancy when a less radical operation such as local surgery, chemotherapy, or irradiation are deemed inadequate or have failed. Many methods have been published for managing the socket, but of primary importance is the need to remove all diseased tissue prior to considering any reconstructive efforts. Options include spontaneous granulation, skin grafting, or muscle flaps. This article will describe the development and the indications for this procedure and will outline the surgical techniques and its complications, the various reconstructive efforts, and survival. The success of orbital exenteration depends on recurrence, histological type, tumor size, and tumor-free margins.

Humans↗
PubMed2000

High prevalence of sleep-disordered breathing in patients with primary open-angle glaucoma.

PURPOSE: Elevated intraocular pressure and systemic hemodynamic changes are main risk factors in primary open-angle glaucoma (POAG). Sleep-disordered breathing (SDB) characterized by snoring, excessive daytime sleepiness and insomnia is accompanied by large swings in blood pressure and repetitive hypoxic periods during sleep. The aim of this study was to evaluate whether there is any relationship between SDB and POAG. METHODS: Consecutively, 212 outpatients with POAG and 218 outpatients without POAG were recruited. Both eyes were examined. An interviewer-administered semi-structured questionnaire was used to collect SDB-related symptoms. RESULTS: After controlling for age, relative to control group, POAG patients showed a high prevalence of snoring (47.6%, p=0.04), snoring plus, excessive daytime sleepiness (27.3%, p=0.01) and snoring plus, excessive daytime sleepiness, plus insomnia (14.6%, p=0.01). CONCLUSION: We found a high prevalence of SDB in patients with POAG. Chronic hemodynamic changes and recurrent severe hypoxia resulting from SDB may contribute to anoxic optic nerve damage, implicated in glaucoma.

Aged↗
PubMed2000

Cyclin-dependent kinase inhibitory protein expression in human choroidal melanoma tumors.

PURPOSE: Recent studies have demonstrated the close link between oncogenesis and cell cycle machinery. Cyclin-dependent kinase inhibitory proteins (CKIs) have been shown to play a critical role in the regulation of cell cycle progression. Alteration of CKI levels and/or functions could be implicated in cell transformation. The three CKIs-p16, p21, and p27-were investigated in human uveal melanoma tumors, and an attempt was made to correlate their levels with clinicopathologic parameters, as well as to p53 and Ki-67 (Mib-1) protein levels. METHODS: Immunochemistry was performed on 32 formalin-fixed, paraffin-embedded specimens of malignant choroidal melanoma. Immunoblot was performed to confirm the immunochemistry study. Prognostic histologic markers such as cell typing, pigmentation, larger tumor dimension, mitotic figures, nucleolar size, scleral invasion, and optic nerve head invasion were reported. RESULTS: Nuclear positivity for p16 was observed in 11 tumors (34%) without any association with clinicopathologic parameters. Tumor cells positive for p21 were detected in 12 choroidal melanomas (37%). Unexpectedly, a positive relationship was seen between p21 and scleral invasion (P: = 0.008). Nuclear positivity for p27 was observed in nine tumors (28%). An inverse correlation was observed between the number of mitotic figures and p27 immunoreactivity (P: = 0.03), as well as between Mib-1 positivity and p27 expression (P: = 0.02). Western blot assays of tumor extracts confirmed overexpression of p21 and p27. CONCLUSIONS: The results suggest that p21 and p27 may be involved in tumorigenesis in choroidal melanoma.

Adult↗
PubMed1999

Survival after malignant tumors of the orbit and periorbit treated by exenteration.

PURPOSE: In order to further assess the survival value of orbital exenteration in malignant orbital and periorbital tumors. METHODS: The charts of 44 patients exenterated for a neoplasm of the orbit or periorbit were reviewed in a retrospective study. RESULTS: The overall 4-year survival was 45%. 26 patients had free margins on histological examination and 24 patients had developed local recurrence or metastasis. Local recurrence or metastasis were significantly more common in the group with transected margins than in the group with free-margins (p= 0.01). Survival between the group of patients with local recurrence or metastasis and the group without local recurrence or metastasis showed statistically significant difference (p=0.0025). In contrast, survival between the group of patients with free margins and the group with transected margins did not show statistically significant difference (p=0.13). CONCLUSION: Surgical free margins section is a key element in successful cancer surgery but seems not the only prognosis variable.

Adolescent↗
PubMed1999

[Cyclin-dependent kinase inhibitory proteins in normal and transformed choroidal melanocytes].

PURPOSE: Recent studies have demonstrated the close link between oncogenesis and cell cycle machinery. Cyclin dependent kinase inhibitory proteins (Ckis) have been shown to be implicated in cancer progression. We investigated the levels of the different regulatory inhibitory proteins involved in the G1 progression and G1/S in choroidal melanomas. METHODS: Immunoblotting, immunoprecipitation and immunohistochemistry were performed on human choroidal cell lines and human choroïdal tumors. RESULTS: Our findings suggested a lack of expression of Cdk inhibitor p21 in two of three melanoma cell lines and a striking underexpression of p27 in the three transformed cell lines. The p16 level was found to be almost the same in both normal and transformed cells, a loss of p16-Cdk4 interaction was observed in two of the three melanoma cell lines. In immunohistochemistry, nuclear positivity for p16 was observed in six tumors. Nuclear positivity for p21 was observed in five tumors. All of theses tumors had scleral invasion (p = 0.003). Nuclear positivity for p27 was observed in only two tumors. CONCLUSION: Our results demonstrate that immunoreactivity for p16, p21 and p27 could be implicated in progression of melanoma tumors. More cases are required to further clarify this issue.

Cell Cycle↗
PubMed1998

Differential expression of G1 cyclins and cyclin-dependent kinase inhibitors in normal and transformed melanocytes.

PURPOSE: To investigate the levels of the different regulatory proteins involved in the G1 progression and G1/S transition in normal and transformed human choroidal melanocytes (CM). METHODS: Three choroidal melanoma cell lines and three CM cultures were used. The purity of the CM cultures was assessed by different approaches, including morphologic study, specific immunostaining, cell proliferation behavior, and transforming growth factor-beta1 responsiveness. The cell cycle protein levels were evaluated by specific immunoblotting of total extracts obtained from the different cell lines. RESULTS: Alterations were observed in the expression of cylins D1 and E in the transformed cells, whereas the amounts of the cyclin-dependent kinases (CDKs) CDK2 and CDK4 were almost identical in both cell types. Although the expression of cyclin H was slightly increased in transformed cells, neither the CDK7 level nor the CDK7 and cyclin H localizations were altered when compared with those in normal CM. The results suggest the absence of the CDK inhibitor (CKI) p21 in two of the three melanoma cell lines and, as a main feature, a striking underexpression of p27 in the three transformed cell lines. Finally, although the p16 level was almost the same in normal and transformed cells, a loss of p16-CDK4 interaction was observed in two of the three melanoma cell lines. CONCLUSIONS: Deregulated expression of G1 cyclins and CKIs and alteration in the interaction of CKIs with CDKs may be implicated in the neoplastic transformation of human ocular melanocytes to malignant melanoma cells.

Cell Division↗
PubMed1997

[Iris metastases. Apropos of 4 cases].

Metastatic tumors of the iris are rare. They most commonly arise from a primary breast or lung neoplasm and are associated with widespread carcinomatosis. They appear as white pink masses; anterior uveitis and hypertony can be seen. They are most often associated with short life expectancy. We report four cases and we show the interest of radiotherapy.

Adult↗
PubMed1997

[Eye disorders in children and adolescents].

PURPOSE: We tried to better characterize non organic ocular disorders in children and adolescents: particularly clinical, perimetric and electrophysiological features. METHODS: We performed a prospective study in 25 cases during a period of 16 months. RESULTS: Non organic ocular disorders were seen among young girls between 9 and 11 years, mostly with bilateral, symmetrical and rapid visual loss. The symptoms were variable in time and responded favorably to suggestion. The ocular examination was normal. Visual field was abnormal in 52% of cases and very often showed a spiral (or snail) picture or a tubular constriction. 7' pattern visual evoked potentials were present in 88% of cases. The acuity was 20/20 in 92% of cases after the consultation and 100% later. CONCLUSION: The ophthalmic and electrophysiologic examination confirmed our diagnosis and eliminated more severe pathology.

Adolescent↗
PubMed1997

[Management of congenital microphthalmos and anophthalmos].

PURPOSE: To better characterize congenital anophthalmos and microphthalmos in order to distinguish which patients need surgical treatment. MATERIALS AND METHODS: A retrospective study of 42 cases with congenital anophthalmos and microphthalmos over a 16 years period was performed. Seven anophthalmos, 20 microphthalmic globes with no associated colobomatous orbital cyst and 15 microphthalmic globes associated with colobomatous orbital cyst were observed. Complete history, pediatrical and ophthalmological examination, electrophysiological feature, oculo-cerebral imagery and karyotype on each of the patients were reviewed. RESULTS: Among all patients, lack of development of the lids was observed in 45% of cases. In our group of anophthalmos, 100% had micro-orbit. In our group of microphthalmic globes with no associated colobomatous orbital cyst, 30% had micro-orbit and in our group of microphthalmic globes associated with colobomatous orbital cyst, 6% had micro-orbit. 75% of patients had ocular anomalies and 39% had systemic anomalies, mostly on the face. Aetiology were found in 36% of cases. Visual evoked potentials and retinal electric feature were useful to better determine visual function. CONCLUSION: Expandable orbital prosthesis would appear to be the most effective therapy for certain cases of anophthalmos and microphthalmos with micro-orbit.

Abnormalities, Multiple↗
PubMed1997

[Surgical treatment of micro-ophthalmic syndromes].

The complex embryology of the oculo-orbito-palpebral region is responsible for a number of heterogeneous clinicopathological situations, associating variable proportions of the three components of the malformation: micro-anophthalmia, microblepharism, micro-orbitism. Application of the double principle of skin expansion for the eyelids and distraction of the callus for the orbit, as early as possible (first year of life), is possible by means of a device which consists of a combination of an intraorbital expansion balloon, an antireflux valve to avoid effective pressure losses in the balloon, and an injection site for progressive filling of the expansion balloon. The response to these treatments is excellent for cases of simple microphthalmia and micro-orbitism; in complex craniofacial malformations, it generally only partially resolves the problem, but provides a precious complement to the quality of the final repair.

Humans↗