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Biomedical subjects

G Oliveri

Publications and source records attributed to G Oliveri.

At least 19 recordsLinked to original sources
PubMed1999

Prognostic meaning of temporary clipping in patients with intracranial aneurysm.

The prognostic meaning of the routine use of the methods of temporary clipping of the afferent vessel in patients with intracranial aneurysm (Grading 0-III) was the aim of the analysis in this study. In the period 1 January, 1991-31 December 1997, 304 patients underwent surgery for non-giant intracranial aneurysm and a follow-up angiography. 157 patients were operated by routinely using the temporary clipping of the afferent vessel, whereas in 147 patients the surgical procedure was performed by traditional methods. The statistical analysis showed a significant reduction (p < 0.001) in terms of risk of surgical complications in the patients who underwent surgery with the temporary clip method compared to those operated with the traditional method, with a relative risk of such complications about three times greater in the latter. The routine use of temporary clipping offers, therefore, the possibility of a significant improvement of the surgical results, not influenced by a further involvement for the structure, due to the short application time.

Aneurysm, Ruptured↗
PubMed1998

Temporary clipping in the surgery of endocranial aneurysms.

The authors' experience in the routine use of temporary clipping procedures in the surgery of endocranial aneurysms is reported. To analyse the validity of such a method we compared the outcome in a series of 153 aneurysms operated according to the traditional procedure (temporary clipping of the afferent vessel only in the case of intraoperative rupture of the aneurysmatic sac) with that of a more recent series of 225 in which the procedure was applied routinely. An unsatisfactory surgical outcome was found in 12.5% and 6.6% of patients respectively, with a corresponding unfavourable outcome in 5.6% and 2.6%.

Humans↗
PubMed1996

17 beta-hydroxysteroid oxidoreductase activity in intact cells significantly differs from classical enzymology analysis.

This paper summarizes our most recent results of steroid enzyme studies on cultured breast and endometrial cancer cells. It deals mainly with estrogen 17 beta-hydroxysteroid oxidoreductase (17 beta HSOR) activity, which presides over estradiol (E2) and estrone (E1) interconversion, a major metabolic pathway of estrogens. Assessment of either the oxidative or reductive component of 17 beta HSOR was carried out on intact cells by means of an original approach based on reverse phase-high performance liquid chromatography and radioactive detection on line. This system allows the continuous monitoring of both precursor degradation and formation of several radiometabolites to assess rates and direction of steroid metabolism. Overall, hormone-responsive, estrogen receptor (ER)-positive cells, regardless of whether they were derived from breast (MCF7) or endometrial (Ishikawa) tumor tissues, showed a prevalence for reductive metabolism (E1-->E2), whilst oxidative pathways (E2-->E1) were largely dominant in non-responsive, ER-poor mammary (MDA-MB231) and endometrial (HEC-1A) cells. The above estimates of 17 beta HSOR activity were at variance with those obtained using the classical enzymology approach, not only in quantitative terms (being markedly lower using intact cell analysis), but also because the prevalent direction of estrogen metabolism was often reversed. Although striking methodological differences may well account for this discrepancy, intact cell analysis is undoubtedly more similar to the in vivo state than the artificial requirements of classical enzymology procedures.

17-Hydroxysteroid Dehydrogenases↗
PubMed1995

Oxidative and reductive pathways of estrogens in hormone responsive and non-responsive human breast cancer cells in vitro.

In order to measure the formation and degradation rates of estradiol by human breast cancer cells, after assessing the biochemical basis of hormone responsiveness and growth response to estrogens, we considered both responsive, estrogen receptor (ER) positive, and non-responsive, ER-negative, breast cancer cell lines, i.e. MCF7, ZR75-1 and MDA-MB231. To this end, we employed a novel "intact cell" approach which allows us, after 24 h incubation, to analyze several enzyme activities in sequence, concurrently with the monitoring of labeled precursor degradation. Our investigations led to the following evidence: (a) the reductive activity of the 17 beta-hydroxysteroid oxoreductase (17 beta-HSOR) appears to be higher than the oxidative only in responsive, ER-rich MCF7 and ZR75-1 cells, as also previously observed by others; (b) this activity is, on the contrary, much lower in MDA-MB231 cells and other unresponsive, ER-poor breast cancer cell lines; (c) conversely, the oxidative activity shows an opposite pattern, being limited in MCF7 and ZR75-1 cells and much higher in MDA-MB231 cells. Overall, a 17 beta-HSOR reductive pathway prevails in both MCF7 and ZR75-1 cells, whilst the oxidative pathway is prevalent in MDA-MB231 cells, leading to a large formation of estrone that is no further metabolized, at least in the experimental conditions used. Our results may provide a likely explanation of previous data on the different estrogen content of breast tumor tissues.

Breast Neoplasms↗
PubMed1995

17 beta-Hydroxysteroid dehydrogenase activity in endometrial cancer cells: different metabolic pathways of estradiol in hormone-responsive and non-responsive intact cells.

In this paper we report that two human long-term endometrial cancer cell lines, Ishikawa and HEC-1A, exhibit quite different abilities in metabolizing estrogens. As a matter of fact, incubation of Ishikawa cells with close-to-physiological concentrations of estradiol (E2) as precursor resulted in: (1) elevated formation (up to 90%) of E2-sulphate (E2-S), using lower precursor concentrations; (2) very limited conversion to estrone (E1) (< 10% at 24 h incubation), as either free or sulphate; and (3) low but consistent production of other estrogen derivatives, such as 2-hydroxy-estrogens and estriol. Conversely, scant amounts (if any) of E2-S were found in HEC-1A cells, while no detectable formation of other estrogen metabolites could be observed after 24 h. On the other hand, E1 production was significantly greater (nearly 60% at 24 h) than in Ishikawa cells, a large proportion of E1 (over 50% of the total) being formed after only 6 h incubation using time-course experiments. The hypothesis that E2 metabolism could be minor in Ishikawa cells as a consequence of the high rate of E2-S formation encountered is contradicted by the evidence that conversion to E1 also remains limited in the presence of much lower E2-S amounts, seen using higher molar concentrations of precursor. Overall, we observe that 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) activity diverges significantly in intact Ishikawa and HEC-1A endometrial cancer cells. This difference could not merely be accounted for by the diverse amounts of substrate (E2) available to the cells, nor may it be imputed to different levels of endogenous estrogens. It should rather be sought in different mechanisms controlling 17 beta-HSD activity or, alternatively, in the presence of distinct isoenzymes in the two different cell types.

Cell Division↗
PubMed1995

Growth of LNCaP human prostate cancer cells is stimulated by estradiol via its own receptor.

We report that growth of LNCaP human prostate cancer cells is significantly stimulated (up to 120% above control) by physiological estradiol (E2) concentrations. This growth increase appears to be comparable to that induced by either testosterone or dihydrotestosterone, as also reported by others. This paper presents novel illustrative evidence for estrogen-binding proteins and messenger RNA transcripts in LNCaP cells. In fact, 1) the reverse transcriptase-polymerase chain reaction system documented normal messenger RNA for estrogen receptors (ER); 2) the radioligand binding assay allowed the detection of high affinity, reduced capacity binding sites in both soluble and nuclear cell fractions; and 3) the immunocytochemical analysis showed a consistently intensive staining for both ER and progesterone receptors. Compared to other human estrogen-responsive mammary cancer cells, MCF7 and ZR75-1, ER expression in LNCaP cells was not significantly lower, as shown by levels of the ER transcripts, number of sites per cell, or femtomoles per mg DNA as well as the percentage and intensity of immunocytochemical staining. A relative estimate of ER expression obtained by matching LNCaP with another human prostate cancer cell line, PC3, always displayed significantly and consistently higher levels in LNCaP cells. The detection of relatively high type I ER content in either cell compartment of LNCaP cells was paralleled by a highly intensive staining for progesterone receptors. In addition, evidence that the synthetic androgen R1881 did not compete for type I binding of E2 and that any E2-induced growth was completely reversed by the pure antiestrogen ICI-182,780, but unaffected by the antiandrogen Casodex, clearly suggests that the biological response of LNCaP cells to E2 is mediated via its own receptor.

Androgen Antagonists↗
PubMed1991

The transcallosal approach for lesions affecting the lateral and third ventricles. Surgical considerations and results in a series of 42 cases.

The study was carried out on a series of 42 patients who underwent surgery through a midline approach. Lesions were in the anterior part of the third ventricle in 32 cases, in the frontal horns in 6, in the trigone in 3, and in both lateral and third ventricles in 1 case. The third ventricle was approached through Monro's foramen in 22 cases and through an interfornicial route in 9 cases. Surgical mortality occurred in 2 cases (5%). Permanent morbidity occurred in another 2 cases (5%): it consisted of slight intellectual deterioration in one case and slight fixed pyramidal signs in the other. Transient mutism was the most frequently observed postoperative complication. Thirty-one patients were reviewed and submitted to neuropsychological tests in the late postoperative period to investigate the presence of intellectual deterioration or disturbances in the interhemispheric transfer of motor, somataesthetic and visual information. All patients showed only the presence of short-term memory disturbance. Furthermore, 12 patients tested before surgery also showed the presence of short-term memory deficits in the preoperative period. We conclude that a midline approach is the most direct and safe route to the third ventricle as well as to the frontal horns and trigone.

Adolescent↗
PubMed1990

Expression of tenascin and of the ED-B containing oncofetal fibronectin isoform in human cancer.

Tenascin (TN) and the oncofetal ED-B containing fibronectin isoform (B-FN) have been reported to be stromal markers of a number of malignancies. Here we report on studies of the distribution of TN and B-FN in normal adult tissues and in benign and malignant tumors, as well as on the levels of the B-FN mRNA in cultured fetal and non-fetal human fibroblasts originating from different tissues. B-FN has an extremely restricted distribution in normal adult tissues, is not expressed in benign tumors, but is greatly expressed in a high percentage of malignant tumors. On the contrary, human TN in normal adult tissues is less restricted than what has previously been reported and it is largely expressed in a number of both benign and malignant tumors. Moreover, we observed a great variability in the relative amount of B-FN mRNA among the 17 normal human fibroblast cell lines tested. We found very low levels in non-fetal skin fibroblasts and higher levels in fetal lung fibroblasts. We also found differences in the relative amounts of B-FN mRNA between fibroblast cell lines originating from the skin and the lung of the same subject.

Adult↗
PubMed1989

Spinal meningiomas: review of 174 operated cases.

The long-term results obtained in a series of 174 patients operated on for spinal meningiomas are critically analyzed. This series was similar to those of other authors with regard to age, sex, location of the tumors, and clinical presentation. Before surgery, about 70% of the patients were included in Groups I and II (mild neurological impairment), and about 30% of the patients were classified in Groups III and IV (significant to severe neurological impairment, up to paraplegia). Complete tumor removal was achieved in 96.5% of the patients, and surgical mortality was about 1%. Microsurgical technique, which was adopted in the last 29 cases, proved to be very effective in reducing undue damage to the spinal cord and in minimizing the postoperative neurological deficits. Of the 174 patients who underwent surgery, 156 underwent late follow-up study for an average of 15 years (2 patients died in the immediate postoperative period, and 16 patients were lost to follow-up). Twenty-nine patients died of causes unrelated to the spinal meningioma; of the remaining 126 patients, 92% were categorized in Groups I and II, and only 8% in Groups III and IV. The rate of recurrence was 6% (9 patients) among the 150 patients who had complete tumor removal, and the rate of regrowth was 17% (1 patient with anaplastic meningioma) among the 6 patients treated by subtotal removal. The early diagnosis of the disease and the use of microsurgical technique appeared as the most relevant factors for further improvement of the surgical results.

Adolescent↗
PubMed1988

Cerebral scintigraphy with 111indium oxine-labelled leukocytes in the differential diagnosis of intracerebral cystic lesions.

CT scanning and scintigraphy with 111Indium-oxide-labelled white blood cells were used to study 32 cases of intracerebral cystic lesions. The results and the criteria of positivity used to lower the false positive rate are discussed. A new criterion, designed to assess the time course of the scintiscan and so reduce still further the frequency of false positives is put forward.

Adolescent↗
PubMed1988

Microsurgical treatment of intramedullary spinal cord tumours.

A series of 81 patients operated for intramedullary spinal cord tumours over a span of 12 years (1975-1986) is presented. The mean age of the patients was about 37 years and 9 patients were in the paediatric age (0-15 years). In 29 cases (36%) the tumours were located within the cervical region; in 34 cases the tumours were located in the thoracic region (42%) and in 18 cases the tumours were located within the medullary cone (22%). Ependymoma accounted for 52% of the cases (42 cases), astrocytoma for 20% (16 cases), lipoma for 7% (6 cases), hemangioblastoma for 6% (5 cases), metastatic tumours for 5% (4 cases); in the remaining 8 cases (10%) rare or very rare spinal tumours were found. The 9 patients in the paediatric age and 8 additional cases who had undergone previous surgery were then excluded from this review. In 59% of the patients with ependymoma and in 90% of the patients with astrocytoma severe neurological deficit were already present before the operation. Total tumour removal was accomplished in 81% of the cases with ependymoma, total or subtotal removal was achieved in 50% of the cases with astrocytoma. At long term follow-up study fair or good functional results were observed in 19 out of 41 cases of ependymoma (46%) and in 3 cases out of 10 of astrocytoma (30%). The surgical outcome was mostly related to the preoperative neurological conditions and to tumour malignancy grade.

Adolescent↗
PubMed1988

Neuralgia of the intermediate nerve combined with trigeminal neuralgia: case report.

An unusual case of a combination of trigeminal and intermediate nerve neuralgia is presented, caused by vascular compression of both of the nerve roots by different vessels. Because the neuralgia of the intermediate nerve could be cured by a vascular decompression operation, it is suggested to include it among the hyperactive dysfunction syndromes of cranial nerves caused by vascular compression at the root entry zone of the nerves. Therefore also for treatment of this neuralgia the non-destructive vascular decompression operation should be taken into consideration.

Cerebrovascular Disorders↗
PubMed1987

Chronic extradural hematomas of the posterior cranial fossa.

During the past 6 years, seven patients with chronic extradural hematomas have been observed at these hospitals. All had a history of occipital injury. Occipital fracture was demonstrated in five cases (by skull x-ray in three cases, at operation in two). The diagnosis was obtained by computed tomography scan in six cases and by iodoventriculography in one. One patient had an associated cerebral lesion, namely, a contralateral temporoparietal contusion. The interval between injury and operation ranged from 27 to 13 days with a mean of 19 days. Only one patient was not operated on, because he was free from symptoms and the hematoma was small. The course was excellent in all seven cases.

Adolescent↗
PubMed1986

Differential diagnosis of CT-hypodense cranial lesions with indium-111-oxine-labeled leukocytes.

Scintigraphy using indium-111-oxine-labeled white blood cells was used as a complementary diagnostic study in the differential diagnosis of 20 intracerebral cystic lesions for which computerized tomography scanning did not exclude abscess. To lower the rate of false-positive findings with scintiscanning, three criteria of positivity were tested in the 20 lesions. The most stringent criterion yielded 100% sensitivity, 94% specificity, and 96% diagnostic accuracy. The clinical and surgical implications of these results are discussed.

Adult↗
PubMed1985

Cystic cavernous angiomas of the posterior fossa. Report of three cases.

Three histologically verified cases of cystic cavernous angioma of the posterior fossa are reported. The clinical history of these patients is presented, and the diagnostic and surgical problems arising from the extreme rarity of the combination of cerebellar site and cystic nature of the lesion are discussed.

Adult↗