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Biomedical subjects

G Besson

Publications and source records attributed to G Besson.

At least 73 records · Page 4Linked to original sources

[Pituitary adenoma secreting somatotropic hormone. Gigantism and peripheral neuropathy. A case].

Gigantism, an extremely rare condition, develops before puberty or in subjects in whom puberty is not yet completed. Hypersecretion of somatotropic hormone results in a tremendous surge in growth (our patient was 2.36 m tall). Among other clinical symptoms disabling peripheral neuropathy predominates and changes in nerve conduction velocity are not merely due to the increase in height. The increase in growth hormone concentrations combined with hypogonadotrophic hypogonadism with normal prolactinaemia is associated with peculiar cutaneous symptoms and with low levels of sex hormone-binding protein.

Adenoma↗

[Intramandibular segment of Meckel's cartilage in the rabbit embryo. Its cytological expression and osteogenetic fate].

Meckel's cartilage undergoes typical endochondral ossification within a model of the mandible, the ossification of which is then intramembranous. The concurrent development of two different osteogenetic processes in the 28 day-old rabbit embryo results in the formation of a single bony framework. These observations are based upon the assumption that Meckel's cartilage is not merely a supportive, primitive shaft without a definite ontogenetic future role, but rather an active participant in mandibular osteogenesis.

Animals↗

[VIP removes the inhibition of prolactin secretion induced by dopamine in patients with prolactinoma].

PRL responsitivity after Vaso-active intestinal Peptide (VIP) infusion was studied during a Dopamine (DA) infusion, in normal women and women with a prolactinoma. VIP alone (6.2 micrograms/min., 12 min.) increases PRL in normal females, but does not remove DA-induced PRL-decrease (1 microgram X kg X X min.-1). It has no effect in women with prolactinoma. In these women, PRL increases when VIP is administered at the 200th minute of DA infusion (1 microgram X kg/min.). A PRL release by VIP in women with a prolactinoma, could imply the restitution of a DA inhibitory control. The same dose of VIP does not modify PRL, when administered during a 4 microgram X kg/min. infusion of DA, in women with a prolactinoma.

Dopamine↗

[Kinetics of prolactinemia after withdrawal of dopamine perfusion and during the administration of domperidone. Normal and hyperprolactinemic subjects (prolactinomas and suprahypophyseal lesions)].

Fifteen normal menstruating women in the early follicular phase of their menstrual cycle, fifteen patients with prolactin secreting adenomas, two patients with a suprahypophysial lesion and an hyperprolactinemia, underwent a dopamine infusion (4 micrograms/kg/mn for four hours and an orally administration of domperidone (40 mg). Prolactin rebound after the arrest of dopamine infusion and during domperidone are + 400% and + 2,300% in normal subjects. These same studies are followed by similar and reduced prolactin response in suprahypophyseal lesion and prolactinomas. Such results suggest an abnormality of central dopaminergic control and/or a primary abnormality of lactotropes in prolactinomas. In two prolactinomas the normalization of both prolactin level and prolactin responses during the same tests is in favor of a primary abnormality of adenomatous lactotrope. These data justify neuro-surgical adenomectomy.

Adenoma↗

[Prognostic value of the trigemino-facial reflex in severe post-traumatic comas].

The blink reflex (BR) study has been carried out on 40 severe head injury cases (average age 24.3 years). The recording was conducted several times between the 2nd and the 12th day and was repeated during the first month and beyond in prolonged comas. 23 patients did not respond even to high intensity stimuli. 17 patients displayed delayed and low amplitude latency responses: one of the components, early R1 or late R2 could be missing. The existence of a detectable focalized hemispheric lesion had no effect on the disappearance of the delayed lateral response. No BR was observed in mesencephalic, protubering comas and in 4 cases of subcortical and diencephalic comas. BR was observed in subcortical or diencephalic comas and in 5 cases of mesencephalic comas. The evolution of patients who did not display any electrical response during the first recording was unfavourable in 15 cases. Among the 5/8 remaining comatose cases, the BR was missing on the 2nd day and back on the 7th day. Among the 17 patients who displayed BR their evolution proved to be very favourable or favourable in 13 cases. In all the patients who survived beyond a month the response latencies proved normal, yet their amplitude was considerably lowered. The lack of BR is temporary but it is an element of unfavourable prognosis if it persists beyond a span of 8 days.

Adolescent↗

Spontaneous spinal epidural hematoma in a 22-month-old girl.

The authors report the case of a 22-month-old girl who developed cervical pain, neck stiffness, and quadriparesis over 12 days. An epidural hematoma was removed, with complete recovery after 6 months. There was no history of trauma. A search of the literature revealed eight previous cases of spontaneous spinal epidural hematomas in children under the age of 10 years.

Female↗

Persisting recessus infundibuli and empty sella. Case report.

In a patient with thrombosis of the central retinal artery, plain skull radiographs showed an enlarged sella turcica and computerized tomography revealed ventricular dilatation. Neuroradiological examination demonstrated stenosis of the Sylvian aqueduct and an unusual type of empty sella due to intrasellar persistence of the recessus infundibuli and the presence of an intrasellar arachnoidocele. The former anomaly has been reported in only three cases; in none of them was it associated with the latter abnormality.

Arachnoid↗

[Domperidone: a new pharmacodynamic agent for exploration of the hypophysis (author's transl)].

Domperidone is a peripheral antagonist of dopamine which does not cross the blood-brain barrier. It is administered orally in doses of 40 mg and consistently induces a rise in prolactin (delta + 2500 % at 90 minutes; surface under the curve 306,000) on condition that the mammotropic cells are in sufficient numbers and under central dopamine control. Adenomatous mammotrophs do not respond to domperidone (p less than 0.001 difference with controls). Three months after transphenoidal adenomectomy and correction of hyperprolactinaemia, there was no significantly change in the kinetics of prolactin response to the product. Some gonadotrophic hormone-producing adenomas exhibit paradoxical response of GH to L-dopa and domperidone, which disappears after surgical excision.

Benzimidazoles↗

[Disabling segmental occlusion of the vertebral artery. Surgical treatment using a venous by pass from the external carotid to the C1-C2 portion if the vertebral artery (2 cases) (author's transl)].

The authors report the cases of two patients who were severely disabled due to signs and symptoms of vertebrobasilar insufficiency caused by unilateral segmental occlusion of one vertebral artery. The patency of the occluded vertebral artery beyond C3 was demonstrated by a faint angiographic injection through anastomic ascending cervical arteries which provided insufficient blood supply. The opposite vertebral artery was abnormal in both cases: a proximal kinking with intracranial atheromatous stenosis in the first and an atheromatous ostial stenosis in the second one. A venous by pass from the external carotid artery (end to end anastomosis) to the C1-C2 portion of the vertebral artery (en to side anastomosis) was performed through an incision from the tip of the mastoid process along the S.C.M. the division of which was unnecessary. Post operatively the signs and symptoms disappeared immediately. The stability of this result is attested by a follow up period of 13 months in the first case and 9 months in the second one. A control angiogram demonstrated a good supply to the vertebro-basilar system through the bypass, the excellent permeability of which was further confirmed by repeated Doppler ultrasound examinations. The indication of this technique is discussed.

Aged↗

[A rare anomaly of the circle of Willis : infra-optic course of both anterior cerebral arteries: associated aneurysm of the basilar bifurcation (author's transl)].

A rare anomaly of the A1 portion of both ACA associated with a saccular aneurysm of the basilar bifudcation is presented. Based upon this case and eigth other cases in the literature, the anatomical and radiological features of the anomaly are precised : the anomalous artery comes from the internal carotid artery right over the cavernous sinus, very close to the origin of the ophtalmic artery; it rums medailly below the inferior aspect of the optic nerve, thus being projected under the plane of the optic canal on oblique angiograms; finally, it crosses the anterior edge of the optic chiasm up to the interhemispheric fissure. By itself the anomaly is asymptomatic but it should not be considered as a mere curiosity since it has most often been found associated with a variety of cerebral vasculature anomalies and in particular with encor more saccular aneurysms of the circle of Willis.

Brain↗