Biomedical subjects

C Mestdagh

Publications and source records attributed to C Mestdagh.

16 recordsLinked to original sources

PubMed2006

Direct carotid-cavernous fistula: a case report and review of the literature.

A 21-year-old man presented with severe proptosis, chemosis, diplopia and an orbital bruit three weeks after a motor vehicle accident. The intraocular pressure was increased. The suspected diagnosis of a direct carotid-cavernous fistula (CCF) was confirmed by digital substraction arteriography. Placement of a covered stent in the internal carotid artery was performed with rapid resolution of the symptoms and normalization of the intraocular pressure. The epidemiology, pathogenesis, symptomatology, differential diagnosis, treatment and outcome of carotid-cavernous fistulas are discussed.

Adult↗

PubMed2003

Correlation between the loss of thyroglobulin iodination and the expression of thyroid-specific proteins involved in iodine metabolism in thyroid carcinomas.

Progress in biotechnology has provided useful tools for tracing proteins involved in thyroid hormone synthesis in vivo. Mono- or polyclonal antibodies are now available to detect on histological sections the Na(+)/I(-) symporter (NIS) at the basolateral pole of the cell, the putative iodide channel (pendrin) at the apical plasma membrane, thyroperoxidase (TPO), and members of the NADPH-oxidase family, thyroid oxidase 1 and 2 (ThOXs), part of the H(2)O(2)-generating system. The aim of this study was to correlate thyroglobulin (Tg) iodination with the presence of these proteins. Tg, T(4)-containing Tg, NIS, pendrin, TPO, ThOXs, and TSH receptor (TSHr) were detected by immunohistochemistry on tissue sections of normal thyroids and various benign and malignant thyroid disorders. Tg was present in all cases. T(4)-containing Tg was found in the adenomas, except in Hurthle cell adenomas. It was never detected in carcinomas. NIS was reduced in all types of carcinomas, whereas it was detected in noncancerous tissues. Pendrin was not expressed in carcinomas, except in follicular carcinomas, where weak staining persisted. TPO expression was present in insular, follicular carcinomas and in follicular variants of papillary carcinomas, but in a reduced percentage of cells. It was below the level of detection in papillary carcinomas. The H(2)O(2)-generating system, ThOXs, was found in all carcinomas and was even increased in papillary carcinomas. Its staining was apical in normal thyroids, whereas it was cytoplasmic in carcinomas. The TSHr was expressed in all cases, but the intensity of the staining was decreased in insular carcinomas. In conclusion, our work shows that all types of carcinomas lose the capacity to synthesize T(4)-rich, iodinated Tg. In follicular carcinomas, this might be due to a defect in iodide transport at the basolateral pole of the cell. In papillary carcinomas, this defect seems to be coupled to an altered apical transport of iodide and probably TPO activity. The TSHr persists in virtually all cases.

Biomarkers↗

PubMed1998

Pagetic sarcoma of the calvarium: report of two cases.

Two cases of calvarium sarcoma with intracranial extension, consecutive to Paget disease of the skull are presented. The neurosurgical implications of this rare complication of a common disease are reviewed. In both cases, the symptoms of malignant degeneration were unspecific and blurred by the presence of a well-known Paget disease. Increasing headaches, focal neurological deficits and signs of intracranial hypertension were observed. Skull X-rays and Computerised Tomography did not allow to make the difference between Pagetic bone and sarcoma. In the second case, Magnetic Resonance Imaging was the most accurate in determining the precise localisation of the tumour, and the subdural invasion. Extensive surgical resection was carried out, by craniectomy of the tumoural bone, followed by cranioplasty. Dural sinus involvement and tumour hypervascularisation caused important peroperative blood loss in both patients. In the second case, the tumour invaded the subdural space through a Pacchioni granulation. Survival of patients with Pagetic sarcoma seems shorter when compared to post-radiation or primitive osteosarcoma, despite adjuvant therapies, probably because of late diagnosis and incomplete surgical resection. The mean reported survival rate is 6 months. Although the first patient died within 4 months, in the second case, the authors obtained a more than two year survival with aggressive surgery alone. These cases also illustrate the polymorphism of sarcomatous degeneration of Pagetic calvarium, the interest of MRI, and the need for close surveillance of patients with known Pagets disease of the skull.

Aged↗

PubMed1997

Indocyanine green angiography in choroidal osteoma.

BACKGROUND: Choroidal osteoma is a rare choroidal tumor; knowledge of its indocyanine green characteristics is limited. METHODS: The fundus photographs and the fluorescein and indocyanine green angiograms of three patients were reviewed. Each patient was examined at least twice with a follow-up varying from 10 to 60 months. RESULTS: Late-phase fluorescein angiograms allow assessment of the extension of the osteoma as it is variably hyperfluorescent due to tumor staining combined with a variable degree of overlying retinal pigment epithelial changes. The hypofluorescent area observed in the early phase of the indocyanine green angiogram corresponds with the extent of the osteoma but the borders may be difficult to demarcate. In the late phase of the indocyanine green angiogram, hypofluorescence due to choriocapillaris loss and hyperfluorescence due to leakage from abnormal choroidal vessels are combined. Infrared angiography high-lights abnormal choroidal vessels and vascular spiders present on the tumor surface. It is difficult to differentiate these choroidal vascular anomalies from subretinal neovascularization. CONCLUSIONS: We find no homogeneous pattern either on fluorescein or on infrared angiography. The findings may change with follow-up, indicating changes within the tumor or the surrounding tissue that are still poorly understood.

Adult↗

PubMed1992

In vitro study of acute toxic effects of high iodide doses in human thyroid follicles.

The acute effects of increasing doses of sodium iodide were studied on human thyroid follicles isolated from normal paranodular tissue. After 24 h incubation in culture medium, follicles isolated from most thyroids maintained their capacity for 125I accumulation and organification and a normal cellular ultrastructure. 125I accumulation was significantly increased after addition of TSH, whereas 125I organification was not affected. In presence of TSH, numerous follicles had large empty-looking follicular lumina unlabeled on autoradiographies. Follicles incubated for 24 h in the presence of a low concentration (10(-7) M) of iodide retained their function and morphology. However, incubation with a high dose of iodide (10(-3) M) caused marked inhibition of 125I accumulation and organification reaching values similar to those obtained in presence of inhibitors of iodide trapping and organification. At high doses, iodide induced necrosis of thyroid epithelial cells: the percentage of necrotic cells was significantly increased with 10(-5) M and doubled with 10(-3) M as compared to values measured at 10(-7) M. Ultrastructural lesions such as apical blebbing, cytoplasmic fragments desquamation, endoplasmic reticulum vesiculation, and accumulation of lipofuscin in secondary lysosomes were also present. The necrotic effect and the ultrastructural alterations also occurred in the presence of TSH but were prevented by the addition of inhibitors of iodide trapping or organification. These results demonstrate a direct acute toxic effect of iodide in human thyroid cells. The nature of the ultrastructural alterations is in agreement with a mechanism of toxicity involving a free radical attack and lipid peroxidation as observed in other tissues.

Cytoplasm↗

PubMed1990

Correlated autoradiographic and ion-microscopic study of the role of iodine in the formation of "cold" follicles in young and old mice.

The role of iodine in the formation of "cold" follicles (not labeled on autoradiograms after radioiodine administration) was analysed in ICR female mice during aging and involution of thyroid hyperplasia, by use of light and electron microscopy and by comparing autoradiographic and analytical ion-microscopic images for the same follicle in serial sections. The proportion of "cold" and "partly cold" (displaying a patchy or ring labeling pattern on autoradiograms) follicles increased significantly during aging. This increase was more pronounced in old mice fed an iodine-rich diet as compared to mice fed a moderate iodine diet. Similarly, during goiter involution produced by refeeding iodine, the follicular heterogeneity of iodine metabolism was more accentuated with a high dose of iodine, regardless of the age of the mice. The follicular lumina of "hot" and "cold" follicles had the same concentration of stable iodine, as shown by analytical ion microscopy, and the cells of both types of follicles formed colloid droplets in response to TSH. Furthermore, when a goitrogenic treatment was induced in aged mice, some "cold" follicles persisted after 8 days, but all follicles resumed "hot" after 16 days. By analytical ion microscopy, 127iodine was also found inside thyroid cells of old mice, but the cytoplasmic patches of 127iodine were not labeled with 125iodine. They corresponded to lipofuscin pigments and secondary lysosomes, as observed in serial sections at the electron-microscopic level. This intracellular stable iodine could constitute a slow turnover compartment not used for hormone synthesis.

Aging↗

PubMed1990

["Insect bite" and Borrelia].

A case of insect bite with a peculiar evolution is presented. The simultaneous inoculation of Borrelia burgdorferi and the treatment are discussed.

Borrelia burgdorferi Group↗

PubMed1979

[Lethal midline granuloma. A case report].

In their study of a case of lethal midline-granuloma, the authors describe the relations between this affection, Wegener's granulomatosis and lymphoma. The case under review illustrates the difficulty in accurately defining the nosologic picture of the disease. Anatomo-pathological examinations present two possibilities: one being malignant granuloma of the Stewart type, the other that of lymphoma. From its subsequent evolution, we may eventually learn whether this is purely a local illness or represents the onset of a systemic disease.

Granuloma, Lethal Midline↗

PubMed1977