PubMed Health⌕ Search

Biomedical subjects

A Ruelle

Publications and source records attributed to A Ruelle.

At least 37 records · Page 2Linked to original sources
PubMed1990

Pirenzepine-insensitive muscarinic autoreceptors regulate acetylcholine release in human neocortex.

The release of [3H]acetylcholine ([3H]ACh) and its modulation mediated by autoreceptors were investigated in synaptosomes prepared from fresh human cerebral cortex prelabelled with [3H]choline ([3H]Ch) and depolarized in superfusion with 15 mM KCl. The K(+)-evoked release of tritium was almost totally accounted for by unmetabolized [3H]ACh and was largely calcium-dependent. Exogenous ACh decreased the depolarization-evoked release of [3H]ACh in a concentration-dependent manner (EC50 = 1.5 microM). The inhibitory effect of ACh on [3H]ACh release was counteracted by the non-selective muscarinic antagonist atropine. In contrast, the selective M1 receptor antagonist pirenzepine was ineffective. It is concluded that muscarinic autoreceptors regulating the release of ACh are present on cholinergic nerve terminals of human cerebral cortex and appear to belong to a pirenzepine-insensitive subtype.

Acetylcholine↗
PubMed1988

Extracranial posterior inferior cerebellar artery aneurysm causing isolated intraventricular hemorrhage: a case report.

The authors report the unusual case of an aneurysm arising on an extracranial loop of the left posterior inferior cerebellar artery (PICA). The computed tomographic scan showed an isolated hemorrhage in the lateral ventricles, and the lesion was recognized 1.5 cm below the foramen magnum at the level of the atlas. The literature concerning peripheral PICA aneurysms is reviewed and the clinical and radiological features of these lesions are discussed. A tendency for subarachnoid bleeding from distal PICA aneurysm ruptures to spread into the ventricular system is suggested. The diagnosis of distal PICA aneurysm should also be considered in cases of isolated intraventricular hemorrhage without obvious parenchymal or subarachnoid hemorrhage. The need for four-vessel angiography when studying patients suffering from a subarachnoid hemorrhage is stressed.

Adult↗
PubMed1987

Primary extra-skeletal Ewing's sarcoma mimicking a disc protrusion.

One of the rarest cases of primary epidural neoplasm is a soft tissue sarcoma histologically similar to Ewing's sarcoma of the bone. In the literature only eleven cases of such an extra-skeletal Ewing's sarcoma have been described. The authors report an additional case presenting as a disc protrusion in a young male. The authors include some diagnostic, prognostic and nosologic remarks about this condition.

Adolescent↗
PubMed1986

Exostosis as a cause of spinal cord compression.

A patient harboring multiple hereditary exostoses with a long-lasting tetraparesis owing to intraspinal osteochondroma is described. The results of surgical treatment were poor in contrast to the results achieved by other previous authors performing decompression of the spinal cord. The related literature is briefly reviewed and conclusions are drawn in favor of computed tomographic examination of the spine of patients with vertebral complaints.

Adult↗
PubMed1985

Spinal carcinomatous metastases. Retrospective study of 67 surgically treated cases.

A series of 67 surgically treated spinal carcinomatous metastases is reviewed in order to establish the role played by surgery in the management of such a disease. The authors compare the results achieved in two groups of patients treated with a different therapeutic approach: either surgery alone or surgery associated with other therapies (mainly radiotherapy). On this basis, although no ideal treatment for spinal epidural metastases can be established, the authors suggest decompressive laminectomy as a first choice approach in the treatment of patients bearing a scarcely radiosensitive spinal metastasis with a rapidly deteriorating motor function.

Combined Modality Therapy↗
PubMed1985

Long-term prognosis of subarachnoid hemorrhages of unknown etiology.

Forty-nine patients who suffered a spontaneous subarachnoid hemorrhage (SAH), and in whom panangiography did not show the cause of the bleeding, were evaluated after a long follow-up (median 8 years). No relationship was found between outcome and antifibrinolytic treatment or blood pressure level. Angiography was repeated in cases with spasm or after rebleeding: one aneurysm was found (7%). The authors suggest that angiography should be repeated in these circumstances. The early mortality was 2%. Late functional capacity was normal in 94% of the patients. No particular restrictions should therefore be recommended.

Adult↗
PubMed1985

Personal experience with the surgery of spinal meningiomas.

We present a series of 36 surgically treated spinal meningiomas, emphasising that the complaints of a patient with spinal meningioma are too often misinterpreted and ascribed to other, more common, affections of the spine such as spondyloarthrosis or disc prolapse. CT scanning and myelography should be used more routinely, in order to reduce the delay in diagnosing a spinal meningioma. Excision of the dural attachment is not always essential to avoid recurrences.

Aged↗
PubMedDate not supplied

Pituitary metastases as presenting lesions of malignancy.

Metastatic tumors of the pituitary gland and parasellar region are unusual and are generally observed both in an advanced phase of the disease and at autopsy. The occurrence of symptomatic lesions is however quite rare. Though some clinical features may suggest the presence of a metastasis, the diagnosis is unlikely both clinically and radiologically and more common pituitary lesions are generally suspected. The Authors present two very unusual cases in which the pituitary lesions represented the onset symptoms of an otherwise unknown malignancy. Moreover the increased survival of cancer patients and the routine utilization of CT scan and MRI will probably induce, in the next years, a more frequent discovery of pituitary metastases. The Authors suggest that the diagnosis of pituitary metastases should be more closely considered even in the absence of a known primary tumor.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

Intracerebral granular cell tumor. Case report.

The authors report a case of intracerebral granular cell tumor. These neoplasms are uncommon and, particularly, the intracerebral location has been reported only in ten previous cases. The authors discuss the clinical and histological features of these lesions, the histogenesis of which is still controversial. Our data seem furthermore to support the theory that at least in most cases, granular cell tumors are derived from Schwann cells.

Brain Neoplasms↗
PubMedDate not supplied

[Non ossifying fibroma with vertebral localization. Clinical case].

A case of non ossifying fibroma of a vertebral body causing a severe spinal cord compression is reported. A review of the literature shows that in the group of benign neoplasms of bone, non ossifying fibroma is uncommon and that its vertebral location is quite rare. The Authors discuss about the clinical, radiological and pathological features of these lesions which may be diagnostically confusing.

Adult↗
PubMedDate not supplied

Brain metastasis from colon cancer. Case report showing a clinical and CT unusual appearance.

The authors report the case of a patient harbouring a parietal convexity tumor whose clinical and CT features were suggestive of a meningioma. Unexpectedly the tumor was a well differentiated adenocarcinoma from a colon cancer with a markedly PAS positive intragland content represented by wide areas of mucoid degeneration. Brain metastases from colon cancer are usually late occurrences and it is extremely rare that the brain lesion be discovered while the primary tumor is still unknown. The authors discuss about the pathogenesis of the CT appearance of adenocarcinoma which is, usually, slightly hyperdense. On the basis of the reported findings it is suggested that mucoid degeneration may induce the development of a well defined CT pattern represented by a very high density appearance with no contrast enhancement.

Adenocarcinoma↗
PubMedDate not supplied

[Epidural extraskeletal Ewing's sarcoma simulating a herniated disk. Clinical case].

One of the rarest case of primary epidural neoplasm is a soft tissue sarcoma histologically similar to Ewing's sarcoma of the bone. In literature have been described only eleven cases of such extraskeletal Ewing's sarcoma. The authors report an additional case presenting as a disc protrusion in a young male. The Authors include some diagnostic, prognostic and nosologic remarks of this affection.

Adolescent↗