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Biomedical subjects

C Mariani

Publications and source records attributed to C Mariani.

At least 73 records · Page 4Linked to original sources
PubMed1996

Normative data for two neuropsychological tests sensitive to frontal dysfunction.

Interest in frontal functions has progressively increased over recent years; however, despite this, there are only a few "frontal" tasks for which Italian normative data are available. The objective of this study was to obtain reference values for two frontal tests from a random sample of normal adults: the first (the Test of Classification and Recall of Pictures) has been shown to reveal selective impairment in patients with unilateral frontal excision; the second (the Odd-Man-Out Test) derives from tasks which have been used to evaluate frontal functions in animals and detect frontal impairment in Parkinson patients. We tested 100 normal subjects, aged 22 to 79 years, stratified by education according to the Italian school system. The correction grids for both tests are also presented. The usefulness of these tests is represented not only by their sensitivity to frontal impairment, but also by the possibility of dissociating the various cognitive aspects of frontal lobe dysfunction.

Adult↗
PubMed1996

Non-Alzheimer forms of cortical degeneration: frequency in clinical practice and clinical report of six cases.

Recent clinical and neuropathological studies suggest the possibility of distinguishing some forms of cortical degeneration from Alzheimer's disease. We report data on the frequency of non-Alzheimer forms of cerebral atrophy that were diagnosed on the basis of clinical criteria. Six examples of these neurological disorders are described: two patients with Lewy body disease; two patients with frontal lobe type dementia, one of whom had associated features of motor neuron disease; a patient with primary progressive aphasia; and a patient with a familial dementia that was probably an atypical form of Pick's disease.

Aged↗
PubMed1995

The DNA rearrangement that generates the TRK-T3 oncogene involves a novel gene on chromosome 3 whose product has a potential coiled-coil domain.

Oncogenic rearrangements of the NTRK1 gene (also designated TRKA), encoding one of the receptors for the nerve growth factor, are frequently detected in thyroid carcinomas. Such rearrangements fuse the NTRK1 tyrosine kinase domain to 5'-end sequences belonging to different genes. In previously reported studies we have demonstrated that NTRK1 oncogenic activation involves two genes, TPM3 and TPR, both localized similarly to the receptor tyrosine kinase, on the q arm of chromosome 1. Here we report the characterization of a novel NTRK1-derived thyroid oncogene, named TRK-T3. A cDNA clone, capable of transforming activity, was isolated from a transformant cell line. Sequence analysis revealed that TRK-T3 contains 1,412 nucleotides of NTRK1 preceded by 598 nucleotides belonging to a novel gene that we have named TFG (TRK-fused gene). The TRK-T3 amino acid sequence displays, within the TFG region, a coiled-coil motif that could endow the oncoprotein with the capability to form complexes. The TRK-T3 oncogene encodes a 68-kDa cytoplasmic protein reacting with NTRK1-specific antibodies. By sedimentation gradient experiments the TRK-T3 oncoprotein was shown to form, in vivo, multimeric complexes, most likely trimers or tetramers. The TFG gene is ubiquitously expressed and is located on chromosome 3. The breakpoint producing the TRK-T3 oncogene occurs within exons of both the TFG gene and the NTRK1 gene and produces a chimeric exon that undergoes alternative splicing. Molecular analysis of the NTRK1 rearranged fragments indicated that the chromosomal rearrangement is reciprocal and balanced and involves loss of a few nucleotides of germ line sequences.

3T3 Cells↗
PubMed1994

Female sterile tobacco plants are produced by stigma-specific cell ablation.

We identified a tobacco stigma-specific gene, designated STIG1. The STIG1 gene is developmentally regulated and expressed specifically in the stigmatic secretory zone. We used a chimeric STIG1-GUS gene to show that the stigma-specific STIG1 gene expression pattern is controlled primarily at the transcriptional level. We constructed a stigma-specific cytotoxic gene by fusing the STIG1 gene 5' regulatory region with the coding sequence of the Bacillus amyloliquefaciens barnase gene, to assess the role of the stigmatic secretory zone in the pollination process. Pistils of transgenic STIG1-barnase tobacco plants undergo normal development, but lack the stigmatic secretory zone and are female sterile. Pollen grains germinate on the ablated 'stigmatic' surface, but are unable to penetrate the transmitting tissue of the style. Application of stigmatic exudate from wild-type pistils to the ablated surface increases the efficiency of pollen tube germination and growth and restores the capacity of pollen tubes to penetrate the style. Our data demonstrate the importance of the stigmatic secretory zone in the pollination process and provide an approach to identify compounds produced by the stigma that are critical for successful pollination and fertilization to occur.

Amino Acid Sequence↗
PubMed1994

Multiple sclerosis and mitochondrial myopathy: an unusual combination of diseases.

A woman with definite multiple sclerosis (MS) and mitochondrial myopathy is described. There were widespread white matter lesions on magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) abnormalities and evoked response changes. Muscle biopsy showed ragged red fibres (RRFs) and cytochrome c oxidase (CoX) deficiency. Southern blot analysis revealed a large deletion of mitochondrial DNA (mtDNA). The patient may be affected by two unrelated diseases, MS and mitochondrial myopathy, but this combination has never previously been reported.

Biopsy↗
PubMed1994

General paresis: neuropsychological and SPECT study of five cases.

Although much less common than before the advent of the antibiotics, cognitive impairment due to general paresis can still be found in clinical practice. Five patients with general paresis underwent longitudinal neuropsychological assessment; on the occasion of the final evaluation, Single Photon Emission Tomography (SPECT) was also performed in four cases. The most frequent cognitive deficit at admission was long term spatial memory impairment, which was present in four patients. Only the two patients who received the highest dosage of intravenous penicillin therapy showed significant improvement at neuropsychological tests after treatment. SPECT findings included areas of cortical hypoperfusion and/or perfusion asymmetry in three out of four patients.

Brain↗
PubMed1994

Frontal dysfunction in early Parkinson's disease.

Recent studies have suggested that patients with Parkinson's disease (PD) share many of the behavioral deficits found following lesions to the pre-frontal cortex. We assessed the performance of a group of 22 mildly impaired, not-demented parkisonians (I or II Hoehn & Yahr stage) in a test of classification and recall of pictures of familiar objects, which has been demonstrated to be sensitive to frontal damage in patients with unilateral cerebral excision. Parkinsonians utilized fewer categories than normal controls for object classification, while no significant difference was found in the immediate and delayed recall scores. These results support the contention that a subclinical dysfunction of frontal type may be present even in the early stages of PD. A subanalysis of the data suggests that this dysfunction could possibly be aggravated by anticholinergic drugs.

Adult↗
PubMed1993

ADP-ribosylation of nonhistone proteins in HeLa cells: modification of DNA topoisomerase II.

We have studied the nonhistone proteins which are modified by ADP-ribosylation in HeLa cells. When isolated nuclei were incubated with 32P-NAD, the main labeled proteins presented sizes of 170, 116, 70, and 45 kDa. To provide evidence for the identification of the 170-kDa band as DNA topoisomerase II, the enzyme was immunoprecipitated from isolated nuclei incubated with 32P-NAD and a labeled peptide of 170 kDa was observed. The label was sensitive to the action of venom phosphodiesterase which specifically degrades ADP-ribose. ADP-ribosylated proteins were also isolated from HeLa cells by affinity chromatography on boronate-agarose gel. Using a monoclonal antibody against the 170-kDa isoform of topoisomerase II, a single 170-kDa immunoreactive peptide was recognized by Western blot among the retained protein acceptors. When ADP-ribosylation was blocked by treating HeLa cells with 3-aminobenzamide, topoisomerase II was no longer retained on the boronate column. These results provide experimental evidence indicating that DNA topoisomerase II is ADP-ribosylated in HeLa cells. To possibly correlate ADP-ribosylation of nuclear proteins with the extent of DNA damage, permeabilized HeLa cells were incubated with 32P-NAD after treatment with the alkylating agent dimethylsulfate. ADP-ribosylated proteins were isolated by boronate chromatography. A strong increase in the ADP-ribosylation of the poly(ADP-ribose)polymerase was observed, whereas no further modification of topoisomerase II was noted.

Adenosine Diphosphate Ribose↗
PubMed1993

Characterization of the NTRK1 genomic region involved in chromosomal rearrangements generating TRK oncogenes.

TRK oncogenes are created by chromosomal rearrangements linking the tyrosine-kinase domain of the NTRK1 gene (encoding one of the receptors for the nerve growth factor) to foreign activating sequences. TRK oncogenes are frequently detected in human papillary thyroid carcinoma, as result of rearrangements involving at least three different activating genes. We have found that the rearrangements creating all the TRK oncogenes so far characterized fall within a 2.9-kb XbaI/SmaI restriction fragment of the NTRK1 gene. Here we report the nucleotide sequence and the exon organization of this fragment.

Base Sequence↗
PubMed1993

Videothoracoscopic excision of a mediastinal thymoma.

The authors have applied the advances in optics, endotelevision monitoring, and instrumentation that have led to the development of videoendoscopic abdominal surgery to performing major excisional procedures in the thorax. A videothoracoscopic technique for the removal of a mediastinal thymoma is described. The procedure was done on a 24-year-old woman suffering from a benign lymphoepithelial thymoma of the mediastinum. The mediastinal mass was mobilized under videolaparoscopic guidance and extracted from the thorax through a small (4 cm) inframammary incision. The postoperative course was uneventful, and the patient experienced minimal postoperative pain. She was discharged on the 3rd postoperative day with excellent functional and cosmetic results and resumed normal activity 4 days later.

Adult↗
PubMed1993

Expression of TRK-T1 oncogene induces differentiation of PC12 cells.

The TRK-T1 oncogene, isolated from a human thyroid carcinoma, represents a rearranged form of the high affinity nerve growth factor (NGF) receptor encoded by the NTRK1 gene; it is created by an intrachromosomal rearrangement fusing the NTRK1 tyrosine kinase domain to the 5' portion of the TPR gene. We have investigated the effect of the TRK-T1 oncogene in PC12 cells, a model system for studying neuronal differentiation and the mechanism of action of NGF. Here, we report that, in PC12 cells, the TRK-T1 oncogene has a differentiating effect that resembles that of NGF and requires the phosphorylation of the oncoprotein. Our results are consistent with the hypothesis that TRK-T1, as well as the original TRK oncogene, induces PC12 differentiation by mimicking the action of NGF bound to its receptor.

Animals↗