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P Fossati

Publications and source records attributed to P Fossati.

At least 19 recordsLinked to original sources
PubMed1997

[Pituitary radiotherapy. Current data and future prospects].

Some technical improvements have allowed to minimize the frequency of severe complications following fractionated pituitary conventional radiotherapy, without altering its efficiency. "Conformational" radiotherapy is currently under development, aiming at the best fitting of the tumor borders to the irradiation zone, by the means of stereotactic imaging. More recently, radiosurgery has been proposed for pituitary adenomas. It consists in a single high radiation dose to the tumor, by the means of either cobalt minibeams (Gamma Unit) or photon beams from a linear particle accelerator. These techniques require the use of a stereotactic frame and precise 3D imaging in order to tightly superimpose the target volume to the reference isodose. They must not be viewed as an alternative to conventional radiotherapy. They can be applied only to small lesions (less than 20 mm in their maximal axis) which are distant (> 5 mm) from the optic chiasma and nerves. Their efficiency is similar to the one of fractionated conventional radiotherapy, with a shorter response time. In conclusion, radiotherapy can be used safely for pituitary adenomas. It remains however a second line treatment, when surgery has been incomplete and when a simple, effective and inexpensive medical treatment is not possible.

Adenoma↗
PubMed1996

[Gonadotropic adenomas].

Since the advent of immunohistochemical and cell culture techniques, the role of gonadotroph adenomas in hypophyseal disorders appears more important than formerly. A large part of "nonfunctional" adenomas in fact correspond to gonadotroph adenomas in vitro. These adenomas raise many clinical and biological questions since their presentation is not univocal. In addition, diagnosis of these adenomas is important since their spontaneous development leads to neuro-opthalmological complications, which presently are still too often the revealing manifestations of these adenomas.

Adenoma↗
PubMed1996

[Results of sub-inguinal revascularization in the treatment of diabetic ischemic foot].

From January 1993 to August 1995, we performed 60 revascularizations of the lower limb using 65 bypasses in 55 patients (32 men, 23 women, mean age 66.6 yars) with diabetes. Trophic lesions of the foot existed in 57 of the revascularizations, and in 3 cases pain was provoked by the supine position. Supra-articular femoropopliteal bypass was performed in 8 cases, subarticular femoropopliteal bypasses in 25, femorotibial bypasses in 14 and paramalleolar bypasses in 18. There were 6 post-operative deaths. Six major amputations were required including 2 despite patent bypasses. Twenty-nine minor amputations were required for trophic disorders. There were 5 deaths after the postoperative period in which 4 major amputations were required despite patent bypasses in 2 cases. Retarded cicatrization was seen in 13 of the amputation stumps of areas of atrophism. Actuarial survival at 2 years was 77 +/- 6% with primary patency of 53 +/- 9.5% and secondary patency of 74 +/- 7%. The rate of success in saving the lower limb was 80.5 +/- 5.6%. Bypass revascularization has been effective in the treatment of the diabetic ischemic foot. Operative mortality was high, resulting from associated cerebral vascular events and coronary heart disease.

Aged↗
PubMed1994

Pituitary microadenomas: experience with Gd-DOTA-enhanced MR imaging at 0.5 Telsa.

PURPOSE: We report our experience with magnetic resonance imaging at 0.5 Tesla in the radiological diagnosis of pituitary adenomas. METHODS: Over 2 years we performed a prospective study in 38 patients with pituitary microadenomas to assess the potential additional benefit of gadolinium in the detection of small intrasellar lesions. The protocol included three coronal T1-weighted sequences: precontrast, early postcontrast (obtained less than 2 min after injection) and late postcontrast (obtained 5 min after injection). For each sequence lesions were classified according to their visibility into three categories: definite lesion, probable lesion or absent lesion. RESULTS: Lesions were classified as well-defined in 55% of patients on the precontrast study, 89.5% on the early postcontrast study and 60.5% on the late postcontrast study. Of nine microadenomas not detected on the precontrast scans, all were clearly seen on the early post contrast scans; only four were well-defined on the late postcontrast study. Only one lesion was not seen on the early postcontrast study but was well-defined on precontrast study as a spontaneous high-intensity focal area: it was a hemorrhagic microadenoma. CONCLUSION: Our results suggest that the early postcontrast study is the most useful sequence for the detection of microadenomas. Precontrast image is necessary to detect hemorrhagic lesions; the late postcontrast sequence has a low additional diagnostic yield and seems unnecessary unless the other sequences are inconclusive.

Adenoma↗
PubMed1994

Explicit memory, procedural learning and lexical priming in Alzheimer's disease.

Different aspects of memory functions were studied in two groups of patients with Alzheimer's disease (AD) and in normal elderly controls. The tests included: explicit memory tests with free and cued recall, and recognition measures; learning of a motor skill; learning of a perceptual skill with verbal material; a priming task with the word stem completion paradigm. The data confirmed that, besides severe impairment for all measures of explicit memory, AD patients were able to learn and retain normally a motor skill in the rotor pursuit task, even across a long retention interval. Moreover, sparing of procedural learning was not restricted to motor tasks, since patients learned normally a mirror-reading task, demonstrating (a) rapid acquisition of the procedure, and (b) acquisition of item-specific information for repeated words. This last effect is accounted for in terms of repetition priming effects rather than of explicit memory strategies, since patients had also normal repetition effect in the word stem completion paradigm.

Aged↗
PubMed1994

Ovarian stromal hypertrophy in hyperandrogenic women.

OBJECTIVE: By using vaginal endosonography, ovarian stromal hypertrophy has been shown to be a strong diagnostic feature of polycystic ovarian syndrome and related states. However, this sign is difficult to quantify and to correlate with other findings because of its subjectivity. We have evaluated the use of computer assisted analysis of ultrasound scans to provide more objective measurements of ovarian structure and size. DESIGN: We used a computer assisted method for the reading of ultrasound scans. It allowed selective calculation of the stromal area by subtraction of the cyst area from the total ovarian area on a longitudinal ovarian section. PATIENTS: A consecutive series of 57 patients with hyperandrogenism (group 1), 17 patients with hypothalamic anovulation (group 2) and 20 normal women (group 3). RESULTS: By computerized measure, 75% patients from group 1 had a bilateral stromal area above the mean +2 SD (700 mm2) of women from group 3. All patients from group 2 were below this threshold. Serum LH level was above the normal range in 45% patients from group 1. The stromal area correlated positively with the serum delta 4-androstenedione (r = 0.47, P < 0.005) and 17 alpha-hydroxyprogesterone (r = 0.39, P < 0.005) levels, exclusively in group 1. It did not correlate with the basal serum testosterone, LH or insulin levels. The cyst area did not correlate with any hormonal parameter. CONCLUSION: Ovarian stromal hypertrophy is a frequent and specific feature of hyperandrogenism. It correlates with the ovarian androgenic dysfunction. Its presence is not always linked with elevated serum immunoreactive LH levels. Further data are needed to elucidate the role of insulin and ovarian growth factors.

17-alpha-Hydroxyprogesterone↗
PubMed1994

Association of Lhermitte-Duclos and Cowden disease: report of a new case and review of the literature.

Lhermitte-Duclos disease is a rare entity, and its pathological features are unique. Pathological findings are characteristic of the disease, with global hypertrophy of the cerebellum, coarse gyri, and the typical "inverted cortex" pattern. Several associated lesions were noted in many patients with Lhermitte-Duclos disease. It is only recently that an association between Lhermitte-Duclos disease and Cowden disease was reported. Cowden disease, or multiple hamartomas syndrome, is a familial disease associating breast cancer, cutaneomucous tricholemmomas, and various other tumoural and dysplasic conditions. A new case of Lhermitte-Duclos disease associated with Cowden disease is reported. A review of the literature found 72 cases of Lhermitte-Duclos disease; 26 had conditions suggesting Cowden disease and seven were definite cases of Cowden disease. The association of Lhermitte-Duclos disease and Cowden disease is probably underestimated. Cowden disease represents a new form of phakomatosis; Lhermitte-Duclos disease may occur as a sporadic disease, or as part of familial Cowden disease. The possibility of preneoplastic states in Cowden syndrome stresses the importance of a thorough screening when Lhermitte-Duclos disease is diagnosed.

Adult↗
PubMed1994

A step forward in enzymatic measurement of creatinine.

We describe an improved enzymatic ultraviolet absorbance method for assaying creatinine in serum, plasma, and urine. Creatinine is hydrolyzed by creatinine iminohydrolase (EC 3.5.4.21) to ammonia and N-methylhydantoin. The ammonia produced combines with 2-oxoglutarate and NADPH in the presence of glutamate dehydrogenase to yield glutamate and NADP+. The consumption of NADPH, measured by a two-point fixed-time assay, is proportional to the amount of creatinine in the sample. The assay is carried out in two steps: The first step eliminates background absorbance in hyperlipemic samples and endogenous ammonia through a "clearing system" and an isocitrate dehydrogenase-based "ammonia scavenger system"; the second step starts creatinine measurement. The method affords a simple, rapid, and sensitive assay with good precision and extended linearity; it employs working solutions stable at least 4 months. Test results compare closely with those of the isotope dilution-mass spectrometry Definitive Method, the HPLC procedure, and the fuller's earth method. The proposed method is not subject to interference from several metabolites or from the 72 drugs tested. Because it is easily automated, the method is suitable for routine work in clinical laboratories.

Aminohydrolases↗
PubMed1993

[Endocrine and metabolic consequences of massive obesity].

Massive obesity is always accompanied by insulin resistance with hyperinsulinaemia in proportion to the amount of visceral fat, which has repercussions on oxidative and non-oxidative glucose metabolism. The increase of free fatty acids in direct relation to the adipocytic mass reduces the hepatic insulin uptake; it increases the suprahepatic glucose flow and the production of very low density lipoproteins. The adipose tissue exerts a feminizing effect in men and a masculinizing effect in women. Women have disorders of ovulation and hirsutism, with increase of free testosterone and elevation of luteotropic hormone levels. Men have hypoandrism due to excessive aromatization of androgens and oestrogens. The adipose tissue accelerates the turnover of cortisol and facilitates cortisone production, which stimulates ACTH secretion and maintains stimulation of the adrenal cortex. Hyperinsulinism and resistance to insulin also intervene in hormonal regulation. They elevate the insulin-like growth factor 1 (IGF-1) which inhibits the production of growth hormone and reduces its plasma half-life; hyperinsulinism and IGF-1 facilitate ovarian androgen production; hypothalamic disturbances occur by diminution of sensitivity to hypoglycaemia, and there are abnormalities in monoaminergic and serotoninergic control. Bone tissue density is preserved for a long time, as it is in proportion to the fatty mass and to the oestrogen and IGF-1 levels, but it may be gradually reduced by secondary hyperparathyroidism. Thyroid function and thyrotropic regulations are unaffected.

Endocrine System Diseases↗
PubMed1993

Interrelationship between ultrasonography and biology in the diagnosis of polycystic ovarian syndrome.

In order to compare the diagnostic significance of hormonal and ultrasonic criteria of polycystic ovarian syndrome (PCOS), the presence or the absence of ultrasonographic and hormonal features of PCOS were recorded in a heterogeneous population of 90 women presenting with hyperandrogenism and/or menstrual disorders. On clinical and hormonal grounds exclusively, these patients could be separated into five diagnostic subgroups: presumed cases of PCOS (n = 21), idiopathic hirsutism (IH) (n = 26), hypothalamic anovulation (HA) (n = 11), hyperprolactinemia (HPRL) (n = 9), and miscellaneous or undetermined diagnosis (n = 23). By the means of a computed automatic classification of patients (cluster analysis) using five hormonal and ultrasonic criteria of PCOS, four homogeneous clusters of patients were obtained. Cluster #1 (25 patients) had the most characteristic profile of PCOS. It included 15 cases of PCOS and 7 cases of IH. Cluster #4 (47 patients) had the less characteristic profile of PCOS. It included the majority of patients with HA and HPRL and the half of the patients with IH. Cluster #2 included only two hyperandrogenic patients, who were massively obese and in whom ultrasonography may have failed to detect PCOS. Cluster #3 (16 patients) included patients from each diagnostic group, who were gathered together because ultrasonographic and hormonal features were, respectively, present and absent in nearly all of them. With the same analysis, the criteria of PCOS could be graded according to their grouping potential. The presence of an abnormal ovarian stroma by ultrasonography appeared as the most potent criterion. Elevated serum testosterone and androstenedione levels and the polyfollicular pattern of ovaries gave intermediate results, while elevated basal LH level was a much weaker grouping parameter. In conclusion, the automatic classification of patients by cluster analysis using both hormonal and ultrasonographic criteria revealed that the classical diagnostic classification, relying upon hormonal data exclusively, may arbitrarily separate patients having the same disease; and that ultrasonography affords pertinent information that should help provide a better diagnostic definition of PCOS.

Adolescent↗
PubMed1993

[Cholesterol: consensus and controversies, what is the trend in 1993?].

Anatomopathological, biological and epidemiological studies suggest that raised cholesterol concentrations are associated with heightened risk for coronary heart disease. Preventive measures have been recommended by consensus conferences (prudent diet and cholesterol lowering drugs) for a "desirable" level of plasma total cholesterol, i.e.: 1.80 g/l before thirty years and 2 g after thirty years. The debates about the advantage of plasma cholesterol lowering have boosted many controversies after the completion of randomized primary and secondary prevention trials analyses. It was showed an increase in total mortality and a no reduction in fatal coronary events. A series of papers have tried to discourage physicians from identifying subjects with high risk. One has to continue to detect subjects with familial hypercholesterolemia and to treat them following the recommendations of consensus conferences. In the other cases, one has to attach value to HDL-cholesterol and plasma triglyceride levels, especially in patients with hyperinsulinemia, insulin resistance, hypertension and visceral obesity. As lipid oxidation products toxicity, protective diets, as the traditional mediterranean diet containing antioxidant components are important too. Relationships between lipoprotein status and hypercoagulability remains to be investigated to identify predictive factors better than cholesterol for atherothrombosis diseases in subjects at risk.

Adult↗
PubMed1993

[Searching for prolactin microadenoma: scanner or MRI?].

Thirty three hyperprolactinemic women, aged 16-46 years, have been investigated by pituitary CT and MRI scans, searching for a microadenoma. The MRI scan with Gadolinium injection (MRI G+) appeared more efficient than the CT scan to detect a picture highly suggestive of a microprolactinoma (30/33 positive scans vs 21/33, respectively, p = 0.06). However, when the CT scan was performed optimaly (i.e. thin cuts, sequential imaging after iode injection, no artefact), its diagnostic potenty was close to the one of MRI G+, missing only 17.6% of lesions. All these were less than 5 mm in diameter. The indirect signs of microadenoma (focal convexity of the superior surface of pituitary, tilting of pituitary stalk, focal sella floor erosion or destruction) had a minimal value. Their sensitivity was 66.6% and 63.3 for convexity, and 63.3 and 46.6% for tilting of pituitary stalk, by MRI and CT scans, respectively. Therefore, they did not afford any help in our experience. Considering the cost and the limited accessibility of MRI, at least in our country, we advise to use CT scan as the primary morphologic means to detect a microadenoma.

Adolescent↗
PubMed1992

[Insulin resistance and polycystic ovary syndrome].

The causes and consequences of the insulin resistance that accompanies the polycystic ovary Syndrome (PCOS) are still controversial. The hyperandrogenism does not appear any more as a causal factor but on the contrary is likely to be a consequence, via the ovarian effects of hyperinsulinism. These are still not clearly understood in their molecular aspects, but their reality is undoubtful in view of some clinical studies which showed an improvement following by the reduction of hyperinsulinism. Therefore, the aetiopathogenic role of the insulin resistance in PCOS becomes more and more obvious but it cannot be split from the likely implication of the intra-ovarian growth factors, and more especially the IGF 1 which could act synergistically with it. Moreover, the presence of LH seems to be still a pre-requisite to the ovarian action of insulin. The therapeutical incidences of these hypothesis are obvious and should improve in the next future the medical management of PCOS.

Androgens↗