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Biomedical subjects

C Mariani

Publications and source records attributed to C Mariani.

At least 91 records · Page 5Linked to original sources
PubMed1992

Influence of poly(ADP ribose) polymerase depletion on promotion of liver carcinogenesis.

In previous studies we demonstrated that liver poly(ADP ribose) polymerase (pADPRP) activity was lost in animals exposed to N-2-acetylaminofluorene (2AAF) according to the Teebor and Becker experimental model (Cancer Res 31:1-3, 1971). In addition, we used the resistant hepatocyte model of Solt and Farber (Nature 263:702-703, 1976) to further investigate pADPRP activity during the multistep process of liver carcinogenesis. A marked depletion of the catalytic protein was evidenced after 2AAF exposure, confirming previous results and indicating a specific effect of 2AAF on this nuclear enzyme that controls conformational changes of chromatin and regulates several catalytic activities in the nucleus. The levels of pADPRP mRNA, measured by northern blot analysis using both experimental models, indicate that the enzyme depletion is not due to a loss of transcript. Moreover, these data indicate that pADPRP depletion, caused by 2AAF, was also maintained during liver compensatory growth, which is known to induce a rapid and marked increase in pADPRP activity and protein level. Treatment of 2AAF-exposed animals with N-acetyl-L-cysteine not only efficiently protected against DNA damage, but also prevented a rapid depletion of the catalytic protein. Interestingly, these data indicate that the marked loss of liver pADPRP occurred during the promotion step induced by 2AAF feeding and that this loss was observed using different models for experimental hepatocarcinogenesis. This phenomenon can be ascribed to a highly defective transcript that cannot be correctly translated into the specific protein or to a rapid degradation of the translated protein.

2-Acetylaminofluorene↗
PubMed1992

Developmental expression of tobacco pistil-specific genes encoding novel extensin-like proteins.

We have sought to identify pistil-specific genes that can be used as molecular markers to study pistil development. For this purpose, a cDNA library was constructed from poly(A)+ RNA extracted from tobacco stigmas and styles at different developmental stages. Differential screening of this library led to the isolation of cDNA clones that correspond to genes preferentially or specifically expressed in the pistil. Seven of these cDNA clones encode proteins containing repetitions of the pentapeptide Ser-Pro4, which is a typical motif found in extensins. Unlike extensin genes, the extensin-like genes described here are not induced under stress conditions. RNA gel blot hybridizations demonstrated the organ-specific expression of the extensin-like genes and their temporal regulation during pistil development. After pollination, the transcript levels of the pistil-specific extensin-like genes change relative to levels in unpollinated pistils. In situ hybridization experiments showed that at least one of these pistil-specific genes is specifically expressed in cells of the transmitting tissue. The possible roles of the extensin-like proteins in pistils are discussed.

Amino Acid Sequence↗
PubMed1992

Very high collagen increase in placentae of smoking mothers.

In 55 placentae, collected at term from clinically normal pregnancies, hydroxyproline was assayed. Thirty were from mothers who smoke and 25 from nonsmokers. In placentae of smokers, hydroxyproline concentration was 42.77 +/- 8.77 micrograms/mg of tissue and in these of nonsmokers 22.52 +/- 7.46 micrograms/mg. Such high a difference discloses a large increment in placental collagen production in smokers, which may account for some of the noxious effects of tobacco on pregnancy.

Evaluation Studies as Topic↗
PubMed1992

Videoendoscopic pulmonary lobectomy for cancer.

A videothoracoscopic right lower pulmonary lobectomy is reported. The excision was done in a 71-year-old man suffering from an adenocarcinoma of the right lower lobe, with an apparent absence of lymphnodal and systemic metastasis. The procedure has been performed using four 10-mm cannulas and a minimal inframammary thoracotomy (4 cm) by inserting a chip camera linked to the thoracoscope and connected to external monitors. The lobar hilar structures were dissected and then sutured-divided with Endo-GIA R shots. The specimen was extracted through the minimal thoracotomy. The postoperative course was uneventful with minimal postoperative pain, and the patient was discharged after complete surgical recovery with excellent functional and cosmetic results. This procedure in selected patients is a new and promising possibility in chest videoendoscopic surgery.

Adenocarcinoma↗
PubMed1991

[Pergolide mesylate in the treatment of Parkinson's disease resistant to other treatments. First Italian experience].

Sixteen parkinsonian patients, mean age 57 (range 41-71), with a mean 9 year duration of Parkinson's disease, with "on-off" motor fluctuations were treated with pergolide mesylate 1.6 mg/die (range 1-5) for three months. The treatment resulted in an improvement of akinesia, tremor and rigidity, of the severity of phase "off" and of the duration of time "on". No significant improvements were obtained in the severity of dyskinesia. Three patients considered the treatment excellent and capable of restoring their working abilities. The drug was generally well tolerated. Pergolide was discontinued because of orthostatic hypotension in two patients and because of hallucinations in one patient. We consider these results a favorable progress in the treatment of Parkinson's disease.

Adult↗
PubMed1991

The natural history and results of surgery in 50 cases of syringomyelia.

In recent years, new neuroimaging techniques have revived interest in syringomyelia with respect to indications and results of surgery. Fifty patients, 36 of whom underwent surgery, have been reviewed. All patients but 3 underwent a new clinical assessment and 33 of them were also neurophysiologically investigated. In approximately one-third of the non-surgically treated patients the clinical course was benign. In 26 of the surgically treated patients an improvement was noted at the short-term assessment both for spasticity and pain, but in most of them it was not maintained in the medium term. Therefore, an accurate selection of the patients to be treated surgically is strongly recommended, particularly when the natural history of the disease is considered. Decompression of the posterior fossa seems to give the best results, yet no curative surgical treatment has been devised to date.

Adolescent↗
PubMed1991

Neuropsychological assessment in multiple sclerosis: a follow-up study with magnetic resonance imaging.

Nineteen moderately impaired patients with clinically definite multiple sclerosis and an initially relapsing-remitting course were included in a neuropsychological and magnetic resonance imaging (MRI) follow-up study. The average test/re-test interval was about 2 years. The neuropsychological findings were indicative of a very mild overall impairment; the patients, as a group, showed no evidence of cognitive deterioration in the follow-up period. A numerical estimation of the severity of cerebral demyelination shown by MRI did not indicate a significant change. No correlation between cognitive performance variations and MRI changes was found.

Adult↗
PubMed1991

Engineered male sterility in plants.

We constructed two chimaeric ribonuclease genes that are specifically expressed in anthers of tobacco and rapeseed plants. The expression of these genes affects the production of functional and viable pollen yielding plants that are male sterile. This dominant gene for nuclear male sterility should facilitate the production of hybrid seed in various crops.

Brassica↗
PubMed1990

Characterization of bioacceptable carbon materials.

Bioacceptable carbon films deposited with a new low temperature technique have been investigated using Raman and X-ray photoelectron spectroscopy. Our results reveal a substantial similarity between the low temperature deposited film and the well-known bioacceptable low temperature isotropic (LTI) pyrocarbon. The Raman spectra, as well as the larger density and oxygen content in the bulk, lead to the speculation of the presence of the common tetrahedral bonds in these materials.

Carbon↗
PubMed1990

Neuropsychological assessment in patients with relapsing-remitting multiple sclerosis and mild functional impairment: correlation with magnetic resonance imaging.

Forty one moderately impaired patients with clinically confirmed multiple sclerosis (MS) and a relapsing-remitting course were submitted to a neuropsychological battery and magnetic resonance imaging (MRI) to correlate the neuropsychological performances with the degree of cerebral demyelination. The neuropsychological results were indicative of a very mild overall impairment. The patients were subdivided into two groups (extensive periventricular demyelination or discrete lesions on MRI) and the results of neuropsychological tests compared. Patients with extensive periventricular demyelination had an inferior performance on concept formation, non-verbal reasoning and verbal memory tests.

Adolescent↗